fertilisation initial seedling: Topics by Science.gov

Sample records for fertilisation initial seedling

Ectomycorrhizal fungi as an alternative to the use of chemical fertilisers in nursery production of Pinus pinaster.

PubMed

Sousa, Nadine R; Franco, Albina R; Oliveira, Rui S; Castro, Paula M L

2012-03-01

Addition of fertilisers is a common practice in nursery production of conifer seedlings. The aim of this study was to evaluate whether ectomycorrhizal (ECM) fungi can be an alternative to the use of chemical fertilisers in the nursery production of Pinus pinaster. A greenhouse nursery experiment was conducted by inoculating seedlings obtained from seeds of P. pinaster plus trees with a range of compatible ECM fungi: (1) Thelephora terrestris, (2) Rhizopogon vulgaris, (3) a mixture of Pisolithus tinctorius and Scleroderma citrinum, and (4) a mixture of Suillus bovinus, Laccaria laccata and Lactarius deterrimus, using forest soil as substrate. Plant development was assessed at two levels of N-P-K fertiliser (0 or 600 mg/seedling). Inoculation with a mixture of mycelium from S. bovinus, L. laccata and L. deterrimus and with a mixture of spores of P. tinctorius and S. citrinum improved plant growth and nutrition, without the need of fertiliser. Results indicate that selected ECM fungi can be a beneficial biotechnological tool in nursery production of P. pinaster. Copyright © 2010 Elsevier Ltd. All rights reserved.
Effect of fertilising with pig slurry and chicken manure on GHG emissions from Mediterranean paddies.

PubMed

Maris, S C; Teira-Esmatges, M R; Bosch-Serra, A D; Moreno-García, B; Català, M M

2016-11-01

Soil fertilisation affects greenhouse gas emissions. The objective of this study was to compare the effect of different fertilisation strategies on N2O, CH4 emissions and on ecosystem respiration (CO2 emissions), during different periods of rice cultivation (rice crop, postharvest period, and seedling) under Mediterranean climate. Emissions were quantified weekly by the photoacoustic technique at two sites. At Site 1 (2011 and 2012), background treatments were 2 doses of chicken manure (CM): 90 and 170kgNH4(+)-Nha(-1) (CM-90, CM-170), urea (U, 150kgNha(-1)) and no-N (control). Fifty kilogram N ha(-1) ammonium sulphate (AS) were topdress applied to all of them. At Site 2 (2012), background treatments were 2 doses of pig slurry (PS): 91 and 152kgNH4(+)-Nha(-1) (PS-91, PS-152) and ammonium sulphate (AS) at 120kgNH4(+)-Nha(-1) and no-N (control). Sixty kilogram NH4(+)-Nha(-1) as AS were topdress applied to AS and PS-91. During seedling, global warming potential (GWP) was ~3.5-17% of that of the whole rice crop for the CM treatments. The postharvest period was a net sink for CH4, and CO2 emissions only increased for the CM-170 treatment (up to 2MgCO2ha(-1)). The GWP of the entire rice crop reached 17Mg CO2-eqha(-1) for U, and was 14 for CM-170, and 37 for CM-90. The application of PS at agronomic doses (~170kgNha(-1)) allowed high yields (~7.4Mgha(-1)), the control of GWP (~6.5MgCO2-eqha(-1)), and a 13% reduction in greenhouse gas intensity (GHGI) to 0.89kgCO2-eqkg(-1) when compared to AS (1.02kgCO2-eqkg(-1)). Copyright © 2016 Elsevier B.V. All rights reserved.
Private initiatives, public support, and war practices: development of fertilisers in Russia.

PubMed

Elina, Olga Y

2011-03-01

The scarcity of experiments with fertilisers, the poor domestic industry, and high prices for imported products made Russia lag far behind the leading agrarian countries in the research and use of fertilisers. The first experiments on fertilisers were connected mostly with the private estates of Russian nobility. Things began to change slowly by the turn of the twentieth century, when the Ministry of Agriculture launched a policy of agricultural science promotion, including the development of agricultural chemistry. It was the outbreak of World War I that created a powerful stimulus for fertiliser research in Russia. A specific Russian "symbiosis" emerged between military industry and agricultural chemistry. The numerous factories of explosives set up ad hoc produced vast amounts of waste products; modified, they could serve as fertilisers. In 1915, the Public Committee for Support of Fertilisers was organised. Eventually, this committee gave birth to the Institute of Fertilisers, the first institute founded by the Bolshevik government. Thus, the project of "chemicalisation of agriculture," usually described as a revolutionary endeavour, was firmly rooted in World War I.
Uncommon but devastating event: total fertilisation failure following intracytoplasmic sperm injection.

PubMed

Goksan Pabuccu, E; Sinem Caglar, G; Dogus Demirkiran, O; Pabuccu, R

2016-03-01

Fertilisation with intracytoplasmic sperm injection (ICSI) is a consequence of complex molecular interactions between spermatozoon and oocyte. Disruption of the process obviously prompts a frustrating event called total fertilisation failure (TFF). Up to 3% of ICSI cycles may result in TFF, and brief counselling for subsequent cycle management is indispensable. Within this perspective, ICSI cycles of a centre over a 10-year period were analysed to document TFF cases. Initial TFF after ICSI and subsequent ICSI cycle of the same cases were documented to clarify predictive factors of successful outcomes after initial TFF. In subsequent cycles, assisted oocyte activation (AOA) with calcium ionophore and Hypo-osmotic swelling test (HOST)/pentoxifilline for sperm selection was used. In the current analysis, successful fertilisation was achieved in 85% of the cases with previous TFF. The significant contributing factors for successful fertilisation in the latter cycle were: improved oocyte quantity and better sperm morphology. In conclusion, sporadic TFF event in the first and only cycle is usually a technically modifiable condition, but repeated TFF could indicate possible gamete defects, which might not be overcomed in the next modified ICSI cycle. © 2015 Blackwell Verlag GmbH.
Weak Evidence of Regeneration Habitat but Strong Evidence of Regeneration Niche for a Leguminous Shrub

PubMed Central

Delerue, Florian; Gonzalez, Maya; Michalet, Richard; Pellerin, Sylvain; Augusto, Laurent

2015-01-01

The identification of an ecological niche specific to the regeneration phase has mobilised significant attention. However, the importance of the regeneration niche concept remains unclear. Our main objective was to study the existence of such a regeneration niche for a leguminous shrub, Ulex europaeus. This study was carried out in southwest France in the context of water and nutrient stresses (mainly phosphorus limitation) due to the presence of nutrient-poor sandy soils. We analysed the regeneration of the species from the germination of seeds and emergence of new seedlings until the seedlings reached young shrub size. Our design included a P fertilisation treatment. We also investigated microsite characteristics (micro-topography and vegetation development) as they can interact with meteorological conditions and determine water availability for seeds and seedlings. We found that P availability controlled seedling growth and the time necessary to reach young shrub size. Water availability appeared to impact the species germination and seedlings survival. We also found that P and water availability depended on the interactions between microsite characteristics and climatic variations. Finally we found evidence that P and water availability are important ecological factors shaping the regeneration niche of the species, but we found weak evidence that any microsite would be appropriate for the regeneration of the species in the long term. Future studies regarding regeneration niches need to distinguish more clearly the ecological factors important for regeneration (the regeneration niche per se) and the physical world where the seedlings appear and develop (the regeneration habitat). PMID:26098877
Fertiliser management effects on dissolved inorganic nitrogen in runoff from Australian sugarcane farms.

PubMed

Fraser, Grant; Rohde, Ken; Silburn, Mark

2017-08-01

Dissolved inorganic nitrogen (DIN) movement from Australian sugarcane farms is believed to be a major cause of crown-of-thorns starfish outbreaks which have reduced the Great Barrier Reef coral cover by ~21% (1985-2012). We develop a daily model of DIN concentration in runoff based on >200 field monitored runoff events. Runoff DIN concentrations were related to nitrogen fertiliser application rates and decreased after application with time and cumulative rainfall. Runoff after liquid fertiliser applications had higher initial DIN concentrations, though these concentrations diminished more rapidly in comparison to granular fertiliser applications. The model was validated using an independent field dataset and provided reasonable estimates of runoff DIN concentrations based on a number of modelling efficiency score results. The runoff DIN concentration model was combined with a water balance cropping model to investigate temporal aspects of sugarcane fertiliser management. Nitrogen fertiliser application in December (start of wet season) had the highest risk of DIN movement, and this was further exacerbated in years with a climate forecast for 'wet' seasonal conditions. The potential utility of a climate forecasting system to predict forthcoming wet months and hence DIN loss risk is demonstrated. Earlier fertiliser application or reducing fertiliser application rates in seasons with a wet climate forecast may markedly reduce runoff DIN loads; however, it is recommended that these findings be tested at a broader scale.
Positive responses of coastal dune plants to soil conditioning by the invasive Lupinus nootkatensis

NASA Astrophysics Data System (ADS)

Hanslin, Hans Martin; Kollmann, Johannes

2016-11-01

Invasive nitrogen-fixing plants drive vegetation dynamics and may cause irreversible changes in nutrient-limited ecosystems through increased soil resources. We studied how soil conditioning by the invasive alien Lupinus nootkatensis affected the seedling growth of co-occurring native plant species in coastal dunes, and whether responses to lupin-conditioned soil could be explained by fertilisation effects interacting with specific ecological strategies of the native dune species. Seedling performance of dune species was compared in a greenhouse experiment using field-collected soil from within or outside coastal lupin stands. In associated experiments, we quantified the response to nutrient supply of each species and tested how addition of specific nutrients affected growth of the native grass Festuca arundinacea in control and lupin-conditioned soil. We found that lupin-conditioned soil increased seedling biomass in 30 out of 32 native species; the conditioned soil also had a positive effect on seedling biomass of the invasive lupin itself. Increased phosphorus mobilisation by lupins was the major factor driving these positive seedling responses, based both on growth responses to addition of specific elements and analyses of plant available soil nutrients. There were large differences in growth responses to lupin-conditioned soil among species, but they were unrelated to selected autecological indicators or plant strategies. We conclude that Lupinus nootkatensis removes the phosphorus limitation for growth of native plants in coastal dunes, and that it increases cycling of other nutrients, promoting the growth of its own seedlings and a wide range of dune species. Finally, our study indicates that there are no negative soil legacies that prevent re-establishment of native plant species after removal of lupins.
Re-evaluation of post-wash sperm is a helpful tool in the decision to perform in vitro fertilisation or intracytoplasmic sperm injection.

PubMed

Wiser, A; Ghetler, Y; Gonen, O; Piura, E; Berkovits, A; Itskovich, A; Rom, T; Shulman, A

2012-04-01

The aim of this study was to find discriminatory parameters, based on sperm characteristics on the day of ovum pickup, that can help guide the decision to perform either intracytoplasmic sperm injection (ICSI) or in vitro fertilisation (IVF). We evaluated 112 cycles fertilised with both regular and ICSI insemination during the same cycle. A total of 112 cycles were analysed. In 62 cycles, fertilisation was obtained with both ICSI and IVF, and in 50 cycles, fertilisation was obtained by ICSI alone. The sperm samples were re-evaluated after the preparation process. The mean initial total motile sperm count (TMSC) was 66.3 × 10(6) ± 47.5 in the group that underwent both methods and 23.1 × 10(6) ± 20.4 in the ICSI only group (P < 0.05). After sperm preparation, the mean post-wash TMSC was 4.4 × 10(6) ± 3.4 and 1.06 × 10(6) ± 0.9 respectively (P < 0.05). A cutoff of 1.5 × 10(6) or fewer sperm after preparation as an indicator for ICSI has a sensitivity of 80% and a specificity of 77%. Re-evaluation of TMSC can prevent unexpected fertilisation failure. Fewer than 1.5 million TMSC after wash should be considered an indication for ICSI fertilisation. © 2011 Blackwell Verlag GmbH.
The Fertile Grounds Initiative: A new way to close nutrient flows at regional level resulting in better agricultural productivity and less environmental losses

NASA Astrophysics Data System (ADS)

van Beek, Christy; van Duivenbooden, Niek; Noij, Gert-Jan

2014-05-01

The threat of declining soil fertility levels is well known. Yet, and despite numerous efforts, we seem incapable of changing the current situation of sink areas in developed countries and depletion areas in developing countries. With negative consequences (i.e. loss in productive capacity and loss in environmental quality) in both areas. Moreover, due to globalization and urbanization nutrient flows become increasingly disconnected. Soil nutrient depletion cannot simply be compensated for with mineral fertilisers, for the following reasons: • mineral fertilisers are often not affordable for smallholders and fertiliser subsidy systems are not always successful • mineral fertilisers do not contain organic matter and therefore do not halt the degradation of the soil • mineral fertilisers work best in combination with organic sources of nutrients (compost, farm yard manure, etc.) • To halt soil degradation an integrated approach is needed, including reducing losses of nutrients and organic matter from soils at risk. Presently, more actors are getting involved in reallocation of nutrients, especially in the energy and waste sector. Time has come for a new approach to bring together demands and supplies for nutrients. We therefore present the Fertile Grounds Initiative: a broker for nutrient supply and demand in the region. The Fertile Grounds Initiative is based on the findings that: • Organic ánd mineral nutrients are required for increased and sustainable production; • Nutrients have a value and should be treated as such; • Due to globalization and urbanization nutrient flows are ever more polarized between depletion and concentration areas; • The demand for energy poses new threats and opportunities for nutrient management. In the Fertile Grounds Initiative nutrient suppliers from the energy sector, waste management, fertilizer companies, etc. and demands for nutrients from farmers are brought together in a dynamic platform. This platform acts as a nutrient bank and integrates different sources of nutrients into high quality crop nutrition products. A capacity building programme ensures proper application of the nutrients and optimal use of on-farm nutrients. To further shape our ideas of the Fertile Grounds Initiative you are cordially invited to become involved.
Dynamic regulation of sperm interactions with the zona pellucida prior to and after fertilisation.

PubMed

Gadella, B M

2012-01-01

Recent findings have refined our thinking on sperm interactions with the cumulus-oocyte complex (COC) and our understanding of how, at the molecular level, the sperm cell fertilises the oocyte. Proteomic analyses has identified a capacitation-dependent sperm surface reordering that leads to the formation of functional multiprotein complexes involved in zona-cumulus interactions in several mammalian species. During this process, multiple docking of the acrosomal membrane to the plasma membrane takes place. In contrast with the dogma that the acrosome reaction is initiated when spermatozoa bind to the zona pellucida (ZP), it has been established recently that, in mice, the fertilising spermatozoon initiates its acrosome reaction during its voyage through the cumulus before it reaches the ZP. In fact, even acrosome-reacted mouse spermatozoa collected from the perivitelline space can fertilise another ZP-intact oocyte. The oviduct appears to influence the extracellular matrix properties of the spermatozoa as well as the COC. This may influence sperm binding and penetration of the cumulus and ZP, and, in doing so, increase monospermic while decreasing polyspermic fertilisation rates. Structural analysis of the ZP has shed new light on how spermatozoa bind and penetrate this structure and how the cortical reaction blocks sperm-ZP interactions. The current understanding of sperm interactions with the cumulus and ZP layers surrounding the oocyte is reviewed with a special emphasis on the lack of comparative knowledge on this topic in humans, as well as in most farm mammals.
Effects of phosphorus availability and genetic variation of leaf terpene content and emission rate in Pinus pinaster seedlings susceptible and resistant to the pine weevil, Hylobius abietis.

PubMed

Blanch, J-S; Sampedro, L; Llusià, J; Moreira, X; Zas, R; Peñuelas, J

2012-03-01

We studied the effects of phosphorus fertilisation on foliar terpene concentrations and foliar volatile terpene emission rates in six half-sib families of Pinus pinaster Ait. seedlings. Half of the seedlings were resistant to attack of the pine weevil Hylobius abietis L., a generalist phloem feeder, and the remaining seedlings were susceptible to this insect. We hypothesised that P stress could modify the terpene concentration in the needles and thus lead to altered terpene emission patterns relevant to plant-insect signalling. The total concentration and emission rate ranged between 5732 and 13,995 μg·g(-1) DW and between 2 and 22 μg·g(-1) DW·h(-1), respectively. Storage and emission were dominated by the isomers α- and β-pinene (77.2% and 84.2% of the total terpene amount amassed and released, respectively). In both resistant and susceptible families, P stress caused an increase of 31% in foliar terpene concentration with an associated 5-fold decrease in terpene emission rates. A higher terpene content in the leaves implies that the 'excess carbon', available under limiting growth conditions (P scarcity), is allocated to terpene production. Sensitive families showed a greater increase in terpene emission rates with increasing P concentrations, which could explain their susceptibility to H. abietis. © 2011 German Botanical Society and The Royal Botanical Society of the Netherlands.
The effects of CO2 and nutrient fertilisation on the growth and temperature response of the mangrove Avicennia germinans.

PubMed

Reef, Ruth; Slot, Martijn; Motro, Uzi; Motro, Michal; Motro, Yoav; Adame, Maria F; Garcia, Milton; Aranda, Jorge; Lovelock, Catherine E; Winter, Klaus

2016-08-01

In order to understand plant responses to both the widespread phenomenon of increased nutrient inputs to coastal zones and the concurrent rise in atmospheric CO2 concentrations, CO2-nutrient interactions need to be considered. In addition to its potential stimulating effect on photosynthesis and growth, elevated CO2 affects the temperature response of photosynthesis. The scarcity of experiments testing how elevated CO2 affects the temperature response of tropical trees hinders our ability to model future primary productivity. In a glasshouse study, we examined the effects of elevated CO2 (800 ppm) and nutrient availability on seedlings of the widespread mangrove Avicennia germinans. We assessed photosynthetic performance, the temperature response of photosynthesis, seedling growth and biomass allocation. We found large synergistic gains in both growth (42 %) and photosynthesis (115 %) when seedlings grown under elevated CO2 were supplied with elevated nutrient concentrations relative to their ambient growing conditions. Growth was significantly enhanced under elevated CO2 only under high-nutrient conditions, mainly in above-ground tissues. Under low-nutrient conditions and elevated CO2, root volume was more than double that of seedlings grown under ambient CO2 levels. Elevated CO2 significantly increased the temperature optimum for photosynthesis by ca. 4 °C. Rising CO2 concentrations are likely to have a significant positive effect on the growth rate of A. germinans over the next century, especially in areas where nutrient availability is high.
Pre-incubation in soil improves the nitrogen fertiliser value of hair waste.

PubMed

Malepfane, N M; Muchaonyerwa, P

2018-01-25

Global generation of human hair waste and its disposal at landfills could contribute to the leaching of nitrates into ground water. High concentrations of nitrogen (N) and other elements suggest that the waste could be a source of plant nutrients and differences in ethnic hair types could affect nutrient release and fertiliser value. The objective of this study was to determine the effects of hair type, as an N source, and pre-incubation time on dry-matter yield, nutrient uptake by spinach (Spinacia oleracea L.) and residual soil nutrients. Salons in Pietermaritzburg provided bulk African and Caucasian hair waste, without distinguishing age, sex, health status or livelihood of the individuals. The hair waste was analysed for elemental composition. A pot experiment was set up under glasshouse conditions. The hair waste was incorporated (400 kg N ha -1 ) into a loamy oxisol and pre-incubated for 0, 28, 56 and 84 days before planting spinach. Potassium (K) and phosphorus (P) were corrected to the same level for all treatments. Spinach seedlings were then cultivated for 6 weeks. Shoot dry-matter and the uptake of all nutrients, except P, were increased by the pre-incubation of hair. African hair pre-incubated for 28 days resulted in greater dry-matter, N, K, Mn and S uptake than Caucasian hair. Increasing pre-incubation resulted in a decline in the residual soil pH and exchangeable K. The findings suggested that pre-incubation improves the N fertiliser value of hair and that African hair has greater value than Caucasian hair when pre-incubated for a short period.
Residual effects of applied chemical fertilisers on growth and seed yields of sunflower (Helianthus annuus cv. high sun 33) after the harvests of initial main crops of maize (Zea mays L.), soybean (Glycine max L.) and sunflower (Helianthus annuus).

PubMed

Srisa-ard, K

2007-03-15

The experiments consisted of two locations, i.e., the first one was carried out on a growers's upland area at Saraburi Province, Central Plane region of Thailand with the use of Chatturat soil series (Typic Haplustalfs, fine, mixed) and the second experiment was carried out at Suranaree Technology university Experimental Farm, Suranaree Technology University Northeast Thailand with the use of Korat soil series (Oxic Paleustults). The experiments aimed to investigate the effect of residual effects of applied chemical fertilisers on growth and seed yields of sunflower (Helianthus annuus) after the harvests of initial main crops of maize, soybean and sunflower. The experiments consisted of four cultural methods being practiced by growers in both regions. For Methods 1 and 2, each had four fertiliser treatments; Method 3 consisted of two fertiliser treatments and Method 4 was used as a control treatment. The results showed that soil pH, organic matter and nutrients of Korat soil series were most suited soil conditions for growth of sunflower plants, whilst that of Chatturat soil series at Saraburi province was an alkaline soil with a mean value of soil pH of 7.8. Chatturat soil series, in most cases, gave higher amounts of seed yields (1,943.75 kg ha(-1)) than Korat soil series. Residual effects of applied chemical fertilisers to main crops of soybean gave better growth and seed yields of sunflower plants and it is considered to be the first choice. The use of sunflower and maize as main crops gave a second choice for subsequent crop of sunflower.
Effects of below-ground insects, mycorrhizal fungi and soil fertility on the establishment of Vicia in grassland communities.

PubMed

Ganade, G; Brown, V K

1997-02-01

The effects of, and interactions between, insect root feeders, vesicular-arbuscular mycorrhizal fungi and soil fertility on the establishment, growth and reproduction of Vicia sativa and V. hirsuta (Fabaceae) were investigated in an early-successional grassland community. Seeds of both species were sown into plots where soil insecticide (Dursban 5G), soil fungicide (Rovral) and soil fertiliser (NPK) were applied in a factorial randomised block design. Fertiliser addition reduced growth, longevity and reproduction of both Vicia species, due to the commonly recorded increase in the competitive advantage of the non-nitrogen-fixing species when nitrogen is added to the plant community. However, in plots where fertiliser was not applied, a reduction in root feeders and mycorrhizal infection led to an increase in seedling establishment and fruit production of V. sativa, and to an increase in flower production for both Vicia species. The interaction between all three soil treatments explained much of the variation in growth and longevity of V. sativa. Plants grew larger and survived longer in plots where natural levels of mycorrhizal infection and root feeders were low compared with plots where all the treatments were applied. This suggests that, although soil nutrient availability was a strong determinant of the performance of these two leguminous species, at natural levels of soil fertility biotic factors acting in the soil, such as mycorrhizal fungi and soil-dwelling insects, were important in shaping the competitive interactions between the two Vicia species and the plant community. Our results indicate that non-additive interactions between ecological factors in the soil environment may strongly affect plant performance.
Short-term effect of nutrient availability and rainfall distribution on biomass production and leaf nutrient content of savanna tree species.

PubMed

Barbosa, Eduardo R M; Tomlinson, Kyle W; Carvalheiro, Luísa G; Kirkman, Kevin; de Bie, Steven; Prins, Herbert H T; van Langevelde, Frank

2014-01-01

Changes in land use may lead to increased soil nutrient levels in many ecosystems (e.g. due to intensification of agricultural fertilizer use). Plant species differ widely in their response to differences in soil nutrients, and for savannas it is uncertain how this nutrient enrichment will affect plant community dynamics. We set up a large controlled short-term experiment in a semi-arid savanna to test how water supply (even water supply vs. natural rainfall) and nutrient availability (no fertilisation vs. fertilisation) affects seedlings' above-ground biomass production and leaf-nutrient concentrations (N, P and K) of broad-leafed and fine-leafed tree species. Contrary to expectations, neither changes in water supply nor changes in soil nutrient level affected biomass production of the studied species. By contrast, leaf-nutrient concentration did change significantly. Under regular water supply, soil nutrient addition increased the leaf phosphorus concentration of both fine-leafed and broad-leafed species. However, under uneven water supply, leaf nitrogen and phosphorus concentration declined with soil nutrient supply, this effect being more accentuated in broad-leafed species. Leaf potassium concentration of broad-leafed species was lower when growing under constant water supply, especially when no NPK fertilizer was applied. We found that changes in environmental factors can affect leaf quality, indicating a potential interactive effect between land-use changes and environmental changes on savanna vegetation: under more uneven rainfall patterns within the growing season, leaf quality of tree seedlings for a number of species can change as a response to changes in nutrient levels, even if overall plant biomass does not change. Such changes might affect herbivore pressure on trees and thus savanna plant community dynamics. Although longer term experiments would be essential to test such potential effects of eutrophication via changes in leaf nutrient concentration, our findings provide important insights that can help guide management plans that aim to preserve savanna biodiversity.
Influence of Fire on Oak Seedlings and Saplings in Southern Oak Woodland on the Santa Rosa Plateau Preserve, Riverside County, California

Treesearch

Earl W. Lathrop; Chris D. Osborne

1991-01-01

One wildfire and two prescription burns were monitored at 15 oak seedling/sapling regeneration sites and at four non-burned comparison sites to study the effect of fire on seedlings and saplings of Quercus engelmannii (Engelmann oak) and Q. agrifolia (coast live oak). The number of initial topkilled seedlings and saplings, initial...
Effects of brash removal after clear felling on soil and soil-solution chemistry and field-layer biomass in an experimental nitrogen gradient.

PubMed

Ring, E; Högbom, L; Nohrstedt, H O

2001-10-12

Biofuels, such as brash from forest fellings, have been proposed as an alternative energy source. Brash removal may affect the sustainability of forest production, e.g., through a change in the availability of cations and N in the soil. We report initial effects of brash removal on inorganic N content in humus and mineral soil, soil-solution chemistry, and field-layer biomass after clear felling an N-fertilisation experiment in central Sweden. The experiment comprised six different fertiliser levels, ranging from 0 to 600 kg N ha(-1). Urea was given every 5th year during 1967 to 1982 to replicated plots, giving total doses of 0 to 2400 kg N ha(-1). Clear felling took place in 1995, 13 years after the last fertilisation. The removal of brash decreased the NO3- content in the humus layer after clear felling. A decrease in the NO3- concentration of the soil solution was indicated during most of the study period as well. No effect of the previous N fertilisation was found in the humus layer, but in the mineral soil there was an increase in NO3- content for the highest N dose after clear felling ( p = 0.06). The soil-solution chemistry and the field-layer biomass showed an irregular pattern with no consistent effects of brash removal or previous fertilisation.
Evaluating different planting stocks for oak regeneration on Hurricane Katrina disturbed lands

Treesearch

Damon B. Hollis; Andrew W. Ezell; Emily B. Schultz; John D. Hodges; Andrew B. Self; Derek K. Alkire

2012-01-01

Three oak planting stocks were evaluated to determine their influence on survival and initial growth. Planting stocks utilized included conventional containerized seedlings in 240 centimeter3 (cm3) containers, 1-0, bareroot seedlings, and Root Production Method (RPMâ¢) seedlings in 11.4 liter (L) containers. Initial height, groundline diameter (...
Effect of long-term fertilisation on the weed community of a winter wheat field.

PubMed

Jiang, Min; Liu, Tao; Huang, Niansheng; Shen, Xinping; Shen, Mingxing; Dai, Qigen

2018-03-05

Effects of fertilisation and other management techniques on a weed community were evaluated during wheat growth in a rice-wheat cropping system. Fertiliser treatments were C0 (C means chemical, C0 means zero chemical fertiliser.), CN (N fertiliser), CNK (N plus K fertiliser), CNPK (N plus P and K fertiliser), CNP (N plus P fertiliser), and CPK (P plus K fertiliser). Weed density, biomass, and bio-diversity were determined. Redundancy analysis (RDA) was used to investigate the relationship between fertiliser management, weed species, and weed density. The overall weed densities in the C0 and CPK treatments were the greatest during wheat seeding and ripening periods and were significantly greater than densities in the other treatments. N, P and organic matter in soil were highly correlated with weed species and density, whereas K in soil was not significantly correlated with weed species and weed density. N fertiliser significantly reduced weed density. Balanced fertilisation maintained weed species richness and resulting in a high yield of wheat. CNPK application reduced weed damage and improved the productivity and stability of the farmland ecosystem.

Estimating the Enduring Effects of Fertiliser Subsidies on Commercial Fertiliser Demand and Maize Production: Panel Data Evidence from Malawi.

PubMed

Ricker-Gilbert, Jacob; Jayne, T S

2017-02-01

Most studies of input subsidy programmes confine their analyses to measuring programme effects over a one-year period. This article estimates the potential longer-run or enduring effects of fertiliser subsidy programmes on smallholder farm households' demand for commercial fertiliser and maize production over time. We use four waves of panel data on 462 farm households in Malawi for whom fertiliser use can be tracked for eight consecutive seasons between 2003/2004 and 2010/2011. Panel estimation methods are used to control for potential endogeneity of subsidised fertiliser acquisition. Results indicate that farmers acquiring subsidised fertiliser in three consecutive prior years are found to purchase slightly more commercial fertiliser in the next year. This suggests a small amount of crowding in of commercial fertiliser from the receipt of subsidised fertiliser in prior years. In addition, acquiring subsidised fertiliser in a given year has a modest positive impact on increasing maize output in that same year. However, acquiring subsidised fertiliser in multiple prior years generates no statistically significant effect on maize output in the current year. These findings indicate that potential enduring effects of the Malawi fertiliser subsidy programme on maize production are limited. Additional interventions that increase soil fertility can make using inorganic fertiliser more profitable and sustainable for smallholders in sub-Saharan Africa and thereby increase the cost-effectiveness of input subsidy programmes.
Sperm retrieval rate and pregnancy rate in infertile couples undergoing in-vitro fertilisation and testicular sperm extraction for non-obstructive azoospermia in Hong Kong.

PubMed

Ko, J Ky; Chai, J; Lee, V Cy; Li, R Hw; Lau, E; Ho, K L; Tam, P C; Yeung, W Sb; Ho, P C; Ng, E Hy

2016-12-01

There are currently no local data on the sperm retrieval and pregnancy rates in in-vitro fertilisation and testicular sperm extraction cycles, especially with regard to the presence of genetic abnormalities. This study aimed to determine the sperm retrieval and pregnancy rates in infertile couples who underwent in-vitro fertilisation and testicular sperm extraction for non-obstructive azoospermia. This retrospective case series was conducted at a tertiary assisted reproduction unit in Hong Kong. Men with non-obstructive azoospermia who underwent in-vitro fertilisation and testicular sperm extraction between January 2001 and December 2013 were included. The main outcome measures were sperm retrieval and pregnancy rates. During the study period, 89 men with non-obstructive azoospermia underwent in-vitro fertilisation and testicular sperm extraction. Sperm was successfully retrieved in 40 (44.9%) men. There was no statistically significant difference in the sperm retrieval rate of those with karyotypic abnormalities (2/5, 40.0% vs 28/61, 45.9%; P=1.000) and AZFc microdeletion (3/6, 50.0% vs 28/61, 45.9%; P=1.000) compared with those without. Sperms were successfully retrieved in patients who had mosaic Klinefelter syndrome (2/3, 66.7%) but not in the patient with non-mosaic Klinefelter syndrome. No sperms were found in men with AZFa or AZFb microdeletions. Pregnancy test was positive in 15 (16.9%) patients and the clinical pregnancy rate was 13.5% (12/89) per cycle. The clinical pregnancy rate per transfer was 34.3% (12/35). The sperm retrieval rate and clinical pregnancy rate per initiated cycle in men undergoing in-vitro fertilisation and testicular sperm extraction in our unit were 44.9% and 13.5%, respectively. No sperms could be retrieved in the presence of AZFa and AZFb microdeletions, but karyotype and AZFc microdeletion abnormalities otherwise did not predict the success of sperm retrieval in couples undergoing in-vitro fertilisation and testicular sperm extraction. Genetic tests are important prior to testicular sperm extraction for patient selection and genetic counselling.
Can δ(15)N in lettuce tissues reveal the use of synthetic nitrogen fertiliser in organic production?

PubMed

Sturm, Martina; Kacjan-Maršić, Nina; Lojen, Sonja

2011-01-30

The nitrogen isotopic fingerprint (δ(15)N) is reported to be a promising indicator for differentiating between organically and conventionally grown vegetables. However, the effect on plant δ(15)N of split nitrogen fertilisation, which could enable farmers to cover up the use of synthetic fertiliser, is not well studied. In this study the use of δ(15)N in lettuce as a potential marker for identifying the use of synthetic nitrogen fertiliser was tested on pot-grown lettuce (Lactuca sativa L.) treated with synthetic and organic nitrogen fertilisers (single or split application). The effect of combined usage of synthetic and organic fertilisers on δ(15)N was also investigated. The δ(15)N values of whole plants treated with different fertilisers differed significantly when the fertiliser was applied in a single treatment. However, additional fertilisation (with isotopically the same or different fertiliser) did not cause a significant alteration of plant δ(15)N. The findings of the study suggest that the δ(15)N value of lettuce tissues could be used as a rough marker to reveal the history of nitrogen fertilisation, but only in the case of single fertiliser application. However, if the difference in δ(15)N between the applied synthetic and organic nitrogen fertilisers was > 9.1 ‰, the detection of split and combined usage of the fertilisers would have greater discriminatory power. 2010 Society of Chemical Industry.
Is there an ideal stimulation regimen for IVF for poor responders and does it change with age?

PubMed Central

Osianlis, Tiki; Catt, James

2008-01-01

Purpose To determine whether there is a superior treatment modality for ‘poor’ responders. Method Retrospective analysis of three stimulation regimens, with patients stratified based on age, stimulation regime and response in previous cycles (“poor’ responder or “non poor” responder). Fertilisation, embryo utilisation and clinical pregnancy rates were assessed. There were a total of 1,608 cycles in the ‘poor’ responder and 8,489 cycles in the ‘non poor’ responder groups. Results In ‘poor’ responders there was no significant difference in fertilisation rate, nor utilisation rate between the three stimulation regimes and no differences in the pregnancy rate/initiated cycle irrespective of age and stimulation regimen in any of the groups. ‘Non poor’ responders had a significantly greater pregnancy rate/initiated cycle for all stimulation regimens in both age groups compared with ‘poor’ responders. Conclusion This large retrospective study of ‘poor’ responders has not shown a difference in pregnancy rates/initiated cycle between stimulation regimens. PMID:18982442
Potential of Bacillus cereus strain RS87 for partial replacement of chemical fertilisers in the production of Thai rice cultivars.

PubMed

Jetiyanon, Kanchalee; Plianbangchang, Pinyupa

2012-03-30

There is increasing interest in the development of technologies which can reduce the requirement for chemical fertilisers in rice production. The objective of this study was to investigate the efficacy of Bacillus cereus strain RS87 for the partial replacement of chemical fertiliser in rice production. A greenhouse experiment was designed using different fertiliser regimes, with and without strain RS87. Six Thai rice cultivars were tested separately. Maximum rice growth and yield were obtained in rice receiving the full recommended fertiliser rate in combination with the strain RS87. Interestingly, all rice cultivars which were treated with strain RS87 and 50% recommended fertiliser rate provided equivalent plant growth and yield to that receiving the full recommended fertiliser rate only. A paired comparison between rice treated with 50% of the recommended fertiliser rate with the bacterial inoculant and the full fertiliser rate alone was further examined in small experimental rice paddy fields. Growth and yield of all rice cultivars which received the 50% fertiliser rate supplemented with strain RS87 gave a similar yield to that receiving the full fertiliser rate alone. Bacterial strain RS87 showed the potential to replace 50% of the recommended fertiliser rate for yield production. Integration of plant growth-promoting rhizobacterial inoculants with reduced application rates of chemical fertiliser appears promising for future agriculture. Copyright © 2012 Society of Chemical Industry.
Effects of Botryosphaeria Inoculation and Stress During Lifting and Outplanting on Initial Growth of Outplanted Sweetgum Seedlings

Treesearch

William Carey; Dave Gerwig; Bert Cregg; Scott Enebak

2004-01-01

A coordinated investigation was carried out with sweetgum seedlings from a nursery in South Carolina (SC) and one in Virginia (VA) to evaluate the effects of cultural practices and Botryosphaeria on the establishment and initial growth of transplanted sweetgum. Seedlings from VA were more sensitive to treatments than those from SC, and date of leaf emergence after...
Immature Loblolly Pine Growth and Biomass Accumulation: Correlations with Seedlings Initial First-Order Lateral Roots

Treesearch

Paul P. Kormanik; Shi-Jean S. Sung; Stanley J. Zarnoch

1998-01-01

Five to seven years after being graded by first-order lateral root (FOLR) numbers and outplanted, loblolly pine (Pinus taeda L.) seedlings were excavated using a commercial tree spade and root systems reevaluated. Current competitive position of trees was related to initial FOLR numbers of 1-0 seedlings. Current FOLR numbers were comparable among tree size classes, but...
Artificial fertilisation in a terrestrial toadlet (Pseudophryne guentheri): effect of medium osmolality, sperm concentration and gamete storage.

PubMed

Silla, Aimee J

2013-01-01

Anurans exhibit a greater reproductive diversity than any other vertebrate order. However, studies investigating the effects of the external fertilisation environment on fertilisation success are limited to aquatic-breeding species. This study investigated the effects of fertilisation medium osmolality, sperm concentration and short-term oocyte storage on fertilisation success in a terrestrial-breeding anuran, Pseudophryne guentheri. Split-clutch experimental designs were used to determine optimal fertilisation conditions. To determine the effect of short-term sperm storage, sperm viability was assessed using fluorescence microscopy and percentage sperm motility and velocity quantified with a computer-assisted sperm analysis system. Fertilisation success was highest in media ranging in osmolality from 25 mOsm kg⁻¹ to 100 mOsm kg⁻¹, representing a broader range and higher optimal osmolality than previously reported for aquatic breeders. High rates of fertilisation (>75%) were achieved in relatively low sperm concentrations (2.5×10⁴ mL⁻¹). Oocytes stored in isotonic solutions (200 mOsm kg⁻¹) retained fertilisation capacity (32%) after 8h of storage, while sperm suspensions maintained motility (≥26%) for 13 days. Additional studies on terrestrial-breeding anurans will be required to ascertain whether the optimal fertilisation conditions reported reflect adaptations to achieve fertilisation in a terrestrial environment.
Drought stress leads to systemic induced susceptibility to a nectrotrophic fungus associated with mountain pine beetle in Pinus banksiana seedlings.

PubMed

Klutsch, Jennifer G; Shamoun, Simon Francis; Erbilgin, Nadir

2017-01-01

Conifers have complex defense responses to initial attacks by insects and pathogens that can have cascading effects on success of subsequent colonizers. However, drought can affect a plant's ability to respond to biotic agents by potentially altering the resources needed for the energetically costly production of induced defense chemicals. We investigated the impact of reduced water on induced chemical defenses of jack pine (Pinus banksiana) seedlings from initial attack by biotic agents and resistance to subsequent challenge inoculation with a pathogenic fungal associate of mountain pine beetle (Dendroctonus ponderosae), Grosmannia clavigera. Applications of phytohormones (methyl salicylate and methyl jasmonate) and G. clavigera were used for initial induction of defenses. Monoterpene concentrations varied with initial induction from fungal and phytohormone application while watering treatment had no effect. Seedlings treated with G. clavigera and methyl jasmonate had the greatest monoterpene concentrations compared to the control and methyl salicylate-treated seedlings. However, the monoterpene response to the challenge inoculation varied with watering treatments, not with prior induction treatments, with lower monoterpene concentrations in fungal lesions on seedlings in the low to moderate watering treatments compared to normal watering treatment. Furthermore, prior induction from phytohormones resulted in systemic cross-induction of resistance to G. clavigera under normal watering treatment but susceptibility under low watering treatment. Seedlings stressed by low water conditions, which also had lower stomatal conductance than seedlings in the normal watering treatment, likely allocated resources to initial defense response but were left unable to acquire further resources for subsequent responses. Our results demonstrate that drought can affect interactions among tree-infesting organisms through systemic cross-induction of susceptibility.
Drought stress leads to systemic induced susceptibility to a nectrotrophic fungus associated with mountain pine beetle in Pinus banksiana seedlings

PubMed Central

Shamoun, Simon Francis; Erbilgin, Nadir

2017-01-01

Conifers have complex defense responses to initial attacks by insects and pathogens that can have cascading effects on success of subsequent colonizers. However, drought can affect a plant’s ability to respond to biotic agents by potentially altering the resources needed for the energetically costly production of induced defense chemicals. We investigated the impact of reduced water on induced chemical defenses of jack pine (Pinus banksiana) seedlings from initial attack by biotic agents and resistance to subsequent challenge inoculation with a pathogenic fungal associate of mountain pine beetle (Dendroctonus ponderosae), Grosmannia clavigera. Applications of phytohormones (methyl salicylate and methyl jasmonate) and G. clavigera were used for initial induction of defenses. Monoterpene concentrations varied with initial induction from fungal and phytohormone application while watering treatment had no effect. Seedlings treated with G. clavigera and methyl jasmonate had the greatest monoterpene concentrations compared to the control and methyl salicylate-treated seedlings. However, the monoterpene response to the challenge inoculation varied with watering treatments, not with prior induction treatments, with lower monoterpene concentrations in fungal lesions on seedlings in the low to moderate watering treatments compared to normal watering treatment. Furthermore, prior induction from phytohormones resulted in systemic cross-induction of resistance to G. clavigera under normal watering treatment but susceptibility under low watering treatment. Seedlings stressed by low water conditions, which also had lower stomatal conductance than seedlings in the normal watering treatment, likely allocated resources to initial defense response but were left unable to acquire further resources for subsequent responses. Our results demonstrate that drought can affect interactions among tree-infesting organisms through systemic cross-induction of susceptibility. PMID:29216258
Effect of fertiliser on functional properties of flour from four rice varieties grown in Sri Lanka.

PubMed

Gunaratne, Anil; Sirisena, Nihal; Ratnayaka, Upul Kumari; Ratnayaka, Jennet; Kong, Xiangli; Vidhana Arachchi, Lal Peruma; Corke, Harold

2011-05-01

Fertiliser is an essential agro-chemical input in modern rice farming. Fertiliser affects the grain quality and yield of rice. Although much research has been carried out to investigate the influence of fertiliser (recommended NPK addition) on yield and quality of rice grain, little is known about the effect of fertiliser on thermal, pasting, gelling and retrogradation properties of rice flour. The aim of this study was to investigate the influence of recommended fertilisation on functional properties of rice flour from four popular high yielding rice varieties grown in Sri Lanka. Fertiliser (recommended NPK addition) increased the protein content but reduced the apparent amylose content in rice flour except in BG 357. Swelling power and amylose leaching were decreased by fertilizer. [corrected] Pasting onset temperature, cold paste viscosity and setback were increased but peak viscosity and granular breakdown decreased. In response to the fertiliser application, gelatinisation peak temperature was reduced in all varieties except BG 300. However, compared to pasting properties, gelatinisation parameters were not much affected by fertilisation. The extent of amylopectin retrogradation was decreased by fertiliser in BG 305 and BG 352 but unchanged in the other two varieties. Except in BG 305, fertiliser reduced the gel hardness of rice flour but increased the gel cohesiveness. It is apparent that the increased protein and reduced amylose content caused by fertiliser affect the functional properties of rice flour. Copyright © 2011 Society of Chemical Industry.
Double-planting can affect gains from weed control treatments

Treesearch

David B. South

2010-01-01

Double-planting is the practice of planting two seedlings at every planting spot. When both seedlings survive, then either the less vigorous seedling is removed or each seedling is given an equal chance of being removed. Some researchers double-plant so that tree growth among experimental plots is not affected by initial differences in stocking. However, double-...
Effect of advance seedling size and vigor on survival after clearcutting

Treesearch

David A. Marquis

1982-01-01

In several separate experiments, it was found that survival of advance seedlings after clearcutting in Allegheny hardwood stands is a function of initial seedling size-larger seedlings survive best. Age, number of leaves, and leaf size also were important determinants of survival. In Allegheny hardwood stands, where advance regeneration is typically less than 1 foot in...
Wrenching Douglas-fir seedlings in August: immediate but no lasting effects.

Treesearch

William I. Stein

1984-01-01

Effects of wrenching Douglas-fir seedlings in August of their second season in the D. L. Phipps State Forest Nursery, Elkton, Oregon, were determined by periodic samplings to learn of changes in phenological, morphological, and growth characteristics. Initial effects of wrenching moderated by January when seedlings were lifted; both wrenched and unwrenched seedlings...
Application of Trichoderma harzianum SQR-T037 bio-organic fertiliser significantly controls Fusarium wilt and affects the microbial communities of continuously cropped soil of cucumber.

PubMed

Chen, Li-Hua; Huang, Xin-Qi; Zhang, Feng-Ge; Zhao, Di-Kun; Yang, Xing-Ming; Shen, Qi-Rong

2012-09-01

The reduction in diversity of the soil microbial community causes the disorder of continuous cropping. The aim of this study was to determine the effects of applying Trichoderma harzianum SQR-T037 bio-organic fertiliser (BIO) on the microbial community in continuously cropped cucumber soil. Four treatments were set: (1) control, where neither seedling nursery soil (N) nor transplanted soil (T) was amended with BIO; (2) N treatment, where nursery soil was amended with BIO (1% w/w) but transplanted soil was not; (3) N + T treatment, where BIO was added to both nursery soil (1% w/w) and transplanted soil (0.5% w/w); (4) uncropped soil, where soil was left uncropped consistently. A disease index of 72.2% was found for the control treatment, while the N and N + T treatments had disease indices of only 25 and 15% respectively. Analysis of the denaturing gradient gel electrophoresis (DGGE) profiles showed that the bacterial communities of the N and N + T treatments were similar to those of the uncropped soil but distinct from those of the control soil. The fungal communities of the N and N + T treatments differed from those of both the uncropped soil and the control. Addition of BIO to both the nursery soil and the transplanted soil can diversify the microbial community in continuously cropped cucumber soil and thus effectively control Fusarium wilt of cucumber plants. Copyright © 2012 Society of Chemical Industry.
Production of 15N-Labelled Liquid Organic Fertilisers Based on Manure and Crop Residue for Use in Fertigation Studies.

PubMed

Martínez-Alcántara, Belén; Martínez-Cuenca, Mary-Rus; Fernández, Carlos; Legaz, Francisco; Quiñones, Ana

2016-01-01

Large quantities of crop residue and animal manure from agricultural and livestock activities are annually produced worldwide. With proper management, these residues are potentially valuable sources of plant nutrients, mainly N. Recycling such subproducts in sustainably-based agricultural systems can minimise the use of mineral fertilisers, and hence reduce the potential risk of surface and groundwater pollution. Therefore, the purpose of this study was to obtain (small scale) two liquid labelled-organic fertilisers, an animal- and a vegetal-based organic (AO and VO, respectively) fertiliser, to be used as organic N sources in subsequent fertigation studies. Forage maize (Zea mays L.) grown under 15N-labelled fertiliser supply was used as raw material for VO fertiliser production, and also as 15N-labelled sheep feed to obtain 15N-labelled manure. The labelled faeces fraction was used as raw material for the AO fertiliser. The VO fertiliser was obtained after an acidic and an enzyme-driven hydrolysis. The AO fertiliser was obtained after acidic hydrolysis. The VO liquid fertiliser presented an N concentration of 330 mg·L-1, 85% of total N was organic, while ammonium and nitrate N accounted for 55% and 45% of the mineral nitrogen fraction, respectively. This fertiliser also exhibited high K, Ca and S concentrations and notable values for the remaining macro- and micronutrients. The AO liquid fertiliser had a similar total N concentration (496 mg·L-1, 82% of total N in an organic form) to that of VO, but its mineral N fraction significantly differed, which came in a predominantly (95%) ammonia form. It also had a high content of N, P, K and other macronutrients, and sufficient Fe, Zn, Mn, Cu and B levels, which suggests its suitability as a potential fertiliser. The percentage of 15N enrichment in both VO and AO liquid fertilisers exceeded 2% 15N atom excess, which enabled their use in subsequent assays run to assess nitrogen uptake efficiency.
Comparison of different fertilisation media for an in vitro maturation?fertilisation?culture system using flow-cytometrically sorted X chromosome-bearing spermatozoa for bovine embryo production.

PubMed

Ferré, Luis B; Bogliotti, Yanina; Chitwood, James L; Fresno, Cristóbal; Ortega, Hugo H; Kjelland, Michael E; Ross, Pablo J

2015-05-13

High demand exists among commercial cattle producers for in vitro-derived bovine embryos fertilised with female sex-sorted spermatozoa from high-value breeding stock. The aim of this study was to evaluate three fertilisation media, namely M199, synthetic oviductal fluid (SOF) and Tyrode's albumin-lactate-pyruvate (TALP), on IVF performance using female sex-sorted spermatozoa. In all, 1143, 1220 and 1041 cumulus-oocyte complexes were fertilised in M199, SOF and TALP, respectively. There were significant differences among fertilisation media (P < 0.05) in cleavage rate (M199 = 57%, SOF = 71% and TALP = 72%), blastocyst formation (M199 = 9%, SOF = 20% and TALP = 19%), proportion of Grade 1 blastocysts (M199 = 15%, SOF = 52% and TALP = 51%), proportion of Grade 3 blastocysts (M199 = 58%, SOF = 21% and TALP = 20%) and hatching rates (M199 = 29%, SOF = 60% and TALP = 65%). The inner cell mass (ICM) and trophectoderm (TE) cells of Day 7 blastocysts were also affected by the fertilisation medium. Embryos derived from SOF and TALP fertilisation media had higher numbers of ICM, TE and total cells than those fertilised in M199. In conclusion, fertilisation media affected cleavage rate, as well as subsequent embryo development, quality and hatching ability. SOF and TALP fertilisation media produced significantly more embryos of higher quality than M199.
Nitrogen levels, top pruning, and lifting date affect nursery development and early field performance of loblolly pine seedlings

Treesearch

Paul P. Kormanik; Taryn L. Kormanik; Shi-Jean S. Sung; Stanley L Zarnoch

1999-01-01

Loblolly pine seedling nursery development and 3-year field performance were contrasted between two nitrogen (N) application regimes and comparable top pruning regimes. Other initial soil nutritional elements were comparable, but high N seedlings received 150 lb/acre N (as NH4NO3) and low N seedlings received half this...
Factors Affecting Seedling Survivorship of Blue Oak (Quercus douglasii H. & A.) in Central California

Treesearch

Frank W. Davis; Mark Borchert; L. E. Harvey; Joel C. Michaelsen

1991-01-01

Blue oak seedling mortality was studied in relation to vertebrate predators, initial acorn planting position, slope and aspect, and oak canopy cover at two sites in the Central Coast Ranges of California. Seedling survival rates (Psd) were related to treatment variables using logistic regression analysis. Analysis of 2842 seedlings for 3 years following establishment...
Cadmium dynamics in soil pore water and uptake by rice: Influences of soil-applied selenite with different water managements.

PubMed

Wan, Yanan; Camara, Aboubacar Younoussa; Yu, Yao; Wang, Qi; Guo, Tianliang; Zhu, Lina; Li, Huafen

2018-05-11

Cadmium (Cd) in rice grains is a potential threat to human health. This study investigated the effects of selenite fertilisation (0 mg kg -1 , 0.5 mg kg -1 , and 1.0 mg kg -1 ) on soil solution Cd dynamics and rice uptake. Rice was grown in two Cd-contaminated soils in Jiangxi and Hunan Provinces under two different sets of conditions: aerobic and flooded. The experiments were conducted in pots. The plants were harvested at the seedling stage and at maturity to determine their Cd levels. Soil solutions were also extracted during the growing season to monitor Cd dynamics. The results showed that in the Jiangxi soil (pH 5.25), Cd concentrations in the soil solutions, seedlings, and mature rice plants were higher under aerobic than under flooded water management conditions. In the Hunan soil (pH 7.26), however, flooding decreased Cd levels in the rice seedlings but not in mature plants. Selenite additions to the Hunan soil decreased Cd concentrations in the soil solutions and in the mature rice plants. These effects were not observed for the solutions or the plants from Jiangxi soil amended with selenite. Relative to the control treatment, 0.5 mg kg -1 selenite decreased the rice grain Cd content by 45.2% and 67.7% under aerobic and flooding conditions, respectively. The results demonstrated that water management regimes affected rice Cd uptake more effectively in Jiangxi than in Hunan soil, whereas selenite addition was more effective in Hunan than in Jiangxi soil. Selenite addition was also more effective at reducing rice grain Cd levels when it was applied under flooding than under aerobic conditions. Copyright © 2018 Elsevier Ltd. All rights reserved.

Seedling Disease Survey in Michigan

USDA-ARS?s Scientific Manuscript database

Stand establishment and persistence continue to be problems for Michigan growers. To determine the extent and severity of the problem, a survey of diseased seedlings from Michigan fields was initiated in 2008. Samples were collected of diseased seedlings for two years. In 2008, samples were collecte...
The effects of pruning treatments and initial seedling morphology on northern red oak seedling growth

Treesearch

Donald J. Kaczmarek; Phillip E. Pope

1993-01-01

Northern red oak (Quercus rubra L.) seedlings exhibit relatively high survival rates following planting, but their growth rates are often slow and extensive stem dieback can occur. This study was designed to investigate the growth responses of northern red oak seedlings planted with or without root-pruning or shoot-pruning. One-year-old (1-0) northern red oak nursery...
The effects of moose (Alces alces L.) on hemlock (Tsuga canadensis (L.) Carr.) seedling establishment in Algonquin Provincial Park, Ontario, Canada

Treesearch

S. A. Vasiliauskas; L. W. Aarssen

2000-01-01

The effects of moose on eastern hemlock (Tsuga canadensis) natural seedling establishment in Algonquin Provincial Park, Ontario, were examined. Two thousand seedlings were tagged on 56 sites in 1992 and monitored for six years. Initial data collected included seedling height, browsing history and percent crown closure. At the end of the growing...
Economic rationale for planting less trees in the face of seedling mortality

Treesearch

Thomas J. Dean; S. Joseph Chang

2002-01-01

Simple economic analyses are used to demonstrate that planting extra trees to compensate for initial seedling mortality can actually reduce the profit expected from a pine plantation. At a 6-percent interest rate, the cost of planting 15 or 25 percent additional seedlings compounded to the end of a 30-year rotation exceeds the revenue lost to these rates of seedling...
Production of 15N-Labelled Liquid Organic Fertilisers Based on Manure and Crop Residue for Use in Fertigation Studies

PubMed Central

Martínez-Alcántara, Belén; Martínez-Cuenca, Mary-Rus; Fernández, Carlos; Legaz, Francisco; Quiñones, Ana

2016-01-01

Large quantities of crop residue and animal manure from agricultural and livestock activities are annually produced worldwide. With proper management, these residues are potentially valuable sources of plant nutrients, mainly N. Recycling such subproducts in sustainably-based agricultural systems can minimise the use of mineral fertilisers, and hence reduce the potential risk of surface and groundwater pollution. Therefore, the purpose of this study was to obtain (small scale) two liquid labelled-organic fertilisers, an animal- and a vegetal-based organic (AO and VO, respectively) fertiliser, to be used as organic N sources in subsequent fertigation studies. Forage maize (Zea mays L.) grown under 15N-labelled fertiliser supply was used as raw material for VO fertiliser production, and also as 15N-labelled sheep feed to obtain 15N-labelled manure. The labelled faeces fraction was used as raw material for the AO fertiliser. The VO fertiliser was obtained after an acidic and an enzyme-driven hydrolysis. The AO fertiliser was obtained after acidic hydrolysis. The VO liquid fertiliser presented an N concentration of 330 mg·L-1, 85% of total N was organic, while ammonium and nitrate N accounted for 55% and 45% of the mineral nitrogen fraction, respectively. This fertiliser also exhibited high K, Ca and S concentrations and notable values for the remaining macro- and micronutrients. The AO liquid fertiliser had a similar total N concentration (496 mg·L-1, 82% of total N in an organic form) to that of VO, but its mineral N fraction significantly differed, which came in a predominantly (95%) ammonia form. It also had a high content of N, P, K and other macronutrients, and sufficient Fe, Zn, Mn, Cu and B levels, which suggests its suitability as a potential fertiliser. The percentage of 15N enrichment in both VO and AO liquid fertilisers exceeded 2% 15N atom excess, which enabled their use in subsequent assays run to assess nitrogen uptake efficiency. PMID:26982183
Enhanced efficiency fertilisers: a review of formulation and nutrient release patterns.

PubMed

Timilsena, Yakindra Prasad; Adhikari, Raju; Casey, Phil; Muster, Tim; Gill, Harsharn; Adhikari, Benu

2015-04-01

Fertilisers are one of the most important elements of modern agriculture. The application of fertilisers in agricultural practices has markedly increased the production of food, feed, fuel, fibre and other plant products. However, a significant portion of nutrients applied in the field is not taken up by plants and is lost through leaching, volatilisation, nitrification, or other means. Such a loss increases the cost of fertiliser and severely pollutes the environment. To alleviate these problems, enhanced efficiency fertilisers (EEFs) are produced and used in the form of controlled release fertilisers and nitrification/urease inhibitors. The application of biopolymers for coating in EEFs, tailoring the release pattern of nutrients to closely match the growth requirement of plants and development of realistic models to predict the release pattern of common nutrients have been the foci of fertiliser research. In this context, this paper intends to review relevant aspects of new developments in fertiliser production and use, agronomic, economic and environmental drives for enhanced efficiency fertilisers and their formulation process and the nutrient release behaviour. Application of biopolymers and complex coacervation technique for nutrient encapsulation is also explored as a promising technology to produce EEFs. © 2014 Society of Chemical Industry.
Intracellular Ca2+ and antioxidant values induced positive effect on fertilisation ratio and oocyte quality of granulosa cells in patients undergoing in vitro fertilisation.

PubMed

Tola, Esra Nur; Mungan, Muhittin Tamer; Uğuz, Abdülhadi Cihangir; Naziroğlu, Mustafa

2013-01-01

Oxidative stress is important for promoting oocyte maturation and ovulation within the follicle through calcium ion (Ca(2+)) influx. The relationship between antioxidant and cytosolic Ca(2+) levels and oocyte quality and fertilisation rate in the granulosa cells of patients undergoing in vitro fertilisation was investigated. Granulosa cells were collected from 33 patients. Cytosolic free Ca(2+) ([Ca(2+)]i) concentration, lipid peroxidation, reduced glutathione, glutathione peroxidase and oocyte quality were measured in the granulosa cells. The relationship between two drug protocols was also examined (gonadotrophin-releasing hormone antagonist and agonist protocols) and the same parameters investigated. The [Ca(2+)]i concentration (P<0.001), glutathione (P<0.05) and oocyte quality (P<0.001) values were significantly higher in the fertilised group than in the non-fertilised group, although glutathione peroxidase activity was significantly (P<0.05) higher in the non-fertilised group than in the fertilised group. The [Ca(2+)]i concentrations were also higher (P<0.001) in the good-quality oocyte groups than in the poor-quality oocyte group. There was no correlation between the two drug protocols and investigated parameters. In conclusion, it was observed that high glutathione and cytosolic Ca(2+) concentrations in granulosa cells of patients undergoing in vitro fertilisation tended to increase the fertilisation potential of oocytes.
Cystic fibrosis transmembrane conductance regulator protein expression rate in healthy spermatozoa is not correlated with ovum fertilisation rate.

PubMed

Li, H-G; Xu, C-M; Chen, W-Y; Shi, Q-X; Ni, Y

2012-05-01

Our previous studies have shown that the cystic fibrosis transmembrane conductance regulator (CFTR) was important for capacitation and fertilisation in mouse, guinea pig and human spermatozoa. However, it is unclear whether CFTR is correlated with ovum fertilisation rate. The present study was to test the possible relationship between spermatozoa CFTR protein expression rate in healthy men and ovum fertilisation rate during in vitro fertilisation. Ninety-four couples for female factor infertility for IVF-ET treatments were retrospectively studied. All the patients were divided into three groups based on the fertilisation rate of ovum in vitro. It was performed to explore whether there were differences in sperm CFTR protein expression rate among the three groups and the relevance between CFTR protein expression rate and ovum fertilisation rate. Our study showed that there was no significant differences in sperm CFTR protein expression rate among the three groups (F = 0.614, P = 0.544), and the relevance between spermatozoa CFTR protein expression rate and ovum fertilisation rate was not significantly different (r = 0.013, P = 0.904). These results further suggest that CFTR protein expression rate in healthy men spermatozoa was not associated with ovum fertilisation rate and thus we cannot predict ovum fertilisation results by sperm CFTR protein expression rate. © 2011 Blackwell Verlag GmbH.
Prevention of multiple pregnancies in couples with unexplained or mild male subfertility: randomised controlled trial of in vitro fertilisation with single embryo transfer or in vitro fertilisation in modified natural cycle compared with intrauterine insemination with controlled ovarian hyperstimulation.

PubMed

Bensdorp, A J; Tjon-Kon-Fat, R I; Bossuyt, P M M; Koks, C A M; Oosterhuis, G J E; Hoek, A; Hompes, P G A; Broekmans, F J M; Verhoeve, H R; de Bruin, J P; van Golde, R; Repping, S; Cohlen, B J; Lambers, M D A; van Bommel, P F; Slappendel, E; Perquin, D; Smeenk, J M; Pelinck, M J; Gianotten, J; Hoozemans, D A; Maas, J W M; Eijkemans, M J C; van der Veen, F; Mol, B W J; van Wely, M

2015-01-09

To compare the effectiveness of in vitro fertilisation with single embryo transfer or in vitro fertilisation in a modified natural cycle with that of intrauterine insemination with controlled ovarian hyperstimulation in terms of a healthy child. Multicentre, open label, three arm, parallel group, randomised controlled non-inferiority trial. 17 centres in the Netherlands. Couples seeking fertility treatment after at least 12 months of unprotected intercourse, with the female partner aged between 18 and 38 years, an unfavourable prognosis for natural conception, and a diagnosis of unexplained or mild male subfertility. Three cycles of in vitro fertilisation with single embryo transfer (plus subsequent cryocycles), six cycles of in vitro fertilisation in a modified natural cycle, or six cycles of intrauterine insemination with ovarian hyperstimulation within 12 months after randomisation. The primary outcome was birth of a healthy child resulting from a singleton pregnancy conceived within 12 months after randomisation. Secondary outcomes were live birth, clinical pregnancy, ongoing pregnancy, multiple pregnancy, time to pregnancy, complications of pregnancy, and neonatal morbidity and mortality 602 couples were randomly assigned between January 2009 and February 2012; 201 were allocated to in vitro fertilisation with single embryo transfer, 194 to in vitro fertilisation in a modified natural cycle, and 207 to intrauterine insemination with controlled ovarian hyperstimulation. Birth of a healthy child occurred in 104 (52%) couples in the in vitro fertilisation with single embryo transfer group, 83 (43%) in the in vitro fertilisation in a modified natural cycle group, and 97 (47%) in the intrauterine insemination with controlled ovarian hyperstimulation group. This corresponds to a risk, relative to intrauterine insemination with ovarian hyperstimulation, of 1.10 (95% confidence interval 0.91 to 1.34) for in vitro fertilisation with single embryo transfer and 0.91 (0.73 to 1.14) for in vitro fertilisation in a modified natural cycle. These 95% confidence intervals do not extend below the predefined threshold of 0.69 for inferiority. Multiple pregnancy rates per ongoing pregnancy were 6% (7/121) after in vitro fertilisation with single embryo transfer, 5% (5/102) after in vitro fertilisation in a modified natural cycle, and 7% (8/119) after intrauterine insemination with ovarian hyperstimulation (one sided P=0.52 for in vitro fertilisation with single embryo transfer compared with intrauterine insemination with ovarian hyperstimulation; one sided P=0.33 for in vitro fertilisation in a modified natural cycle compared with intrauterine insemination with controlled ovarian hyperstimulation). In vitro fertilisation with single embryo transfer and in vitro fertilisation in a modified natural cycle were non-inferior to intrauterine insemination with controlled ovarian hyperstimulation in terms of the birth of a healthy child and showed comparable, low multiple pregnancy rates.Trial registration Current Controlled Trials ISRCTN52843371; Nederlands Trial Register NTR939. © Bensdorp et al 2015.
Establishment of Swamp Tupelo Seedlings After Regeneration Cuts

Treesearch

Dean S. DeBell; J. Dennis Auld

1971-01-01

Environmental factors influencing natural regeneration of swamp tupelo were examined in a study involving five harvest treatments replicated in 3 successive years. Initial seedling establishment was related to seed production, but other factors probably are more limiting in most years. Abundance of established seedlings differed significantly with harvest cuttings,...
Inhibition of coral fertilisation and larval metamorphosis by tributyltin and copper.

PubMed

Negri, A P; Heyward, A J

2001-02-01

Fertilisation and larval metamorphosis of reef-building corals are important life history events leading to recruitment of juvenile corals to reef populations. Little is known of the sensitivity of these early life phases to pollution, or their relative susceptibility to certain toxicants compared with established coral colonies. Inhibition of fertilisation and larval metamorphosis of the coral Acropora millepora (Ehrenberg, 1834) was assessed in response to solutions of the antifoulants tributyltin (TBT) and copper (Cu) using laboratory-based bioassays. Nominal concentrations that inhibited 50% fertilisation and metamorphosis (IC50) were calculated from 4 h fertilisation and 24 h metamorphosis assays and were based on introduced dose. Cu was most potent towards fertilisation with an IC50 of 17.4 micrograms/l. TBT however, proved more toxic to larval metamorphosis having an IC50 of 2.0 micrograms/l. Inert surfaces coated with either Cu- or TBT-based antifouling paint also inhibited fertilisation and metamorphosis. The degree of inhibition was correlated with surface area of the paint coating. These results indicate fertilisation and metamorphosis of coral can be sensitive to active components of antifouling paints.
Fertilisation in the horse and paracrine signalling in the oviduct.

PubMed

Goudet, Ghylène

2011-01-01

The mammalian oviduct plays a crucial role in the preparation of gametes for fertilisation (transport and final maturation) and fertilisation itself. An increasing number of studies offers a comprehensive overview of the functions of the oviduct and its secretions, but this topic has had limited investigation in the horse. Limited data are available on the final oocyte maturation in the equine oviduct. However, in vitro and in vivo systems have been established to analyse the influence of equine oviduct epithelial cells (OEC) during maturation on the potential of oocytes for fertilisation and development. Most studies focus on the role of the oviduct in equine sperm function, such as spermatozoa transport, attachment to oviduct epithelium, viability, motility and capacitation. Moreover, some possible candidate molecules for sperm-oviducal interactions have been identified in the horse. Finally, the low efficiency of conventional in vitro fertilisation and the in vivo fertilisation of equine oocytes transferred into the oviduct of an inseminated mare predicted an influence of oviduct in equine fertilisation. Actually, in vivo and in vitro experiments demonstrated a role of the oviduct in equine fertilisation. Moreover, recent studies showed a beneficial effect of homologous and heterologous OEC on equine in vitro fertilisation, and some candidate molecules have been studied.
The anxiety of Taiwanese women with or without continuity treatment after previous in vitro fertilisation failure.

PubMed

Su, Tsann-Juu; Tzeng, Ya-Ling; Kuo, Pi-Chao

2011-08-01

To compare the anxiety levels of Taiwanese women who continued with in vitro fertilisation treatment and those who discontinued treatment post-in vitro fertilisation failure. In vitro fertilisation is perceived as the last resort of infertility treatment. The impact of unsuccessful in vitro fertilisation treatment on psychological function has been documented; however, research comparing the levels of anxiety of women who cease and those who continue in vitro fertilisation post-failure is scant. A cross-sectional comparative study design was used. Fifty-eight women in whom in vitro fertilisation had failed within the previous year were recruited to this study from a medical centre in northern Taiwan; 34 women continued treatment and 24 discontinued treatment. The State-Trait Anxiety Inventory was used to assess their levels of anxiety. Women in the group who continued treatment exhibited higher state and trait anxiety (TA) than women in the group who discontinued treatment (p < 0·005). The number and frequency of in vitro fertilisation cycles were significantly higher in the group who continued treatment than in those who did not. A strong positive correlation between state and TA (r = 0·8, p < 0·01) existed in both groups. Both groups exhibited considerable levels of anxiety; however, the women who continued in vitro fertilisation treatment had higher levels of anxiety than those who discontinued treatment. The level of anxiety of women who decide to continue in vitro fertilisation treatment should be assessed as early as possible and counselling services provided to women who experience in vitro fertilisation failure should concentrate more on relieving psychological distress. One year after discontinuing treatment, some women still experience considerable anxiety; therefore, the care and assistance provided to these women need to be continually evaluated. © 2011 Blackwell Publishing Ltd.
Prevention of multiple pregnancies in couples with unexplained or mild male subfertility: randomised controlled trial of in vitro fertilisation with single embryo transfer or in vitro fertilisation in modified natural cycle compared with intrauterine insemination with controlled ovarian hyperstimulation

PubMed Central

Bensdorp, A J; Tjon-Kon-Fat, R I; Bossuyt, P M M; Koks, C A M; Oosterhuis, G J E; Hoek, A; Hompes, P G A; Broekmans, F J M; Verhoeve, H R; de Bruin, J P; van Golde, R; Repping, S; Cohlen, B J; Lambers, M D A; van Bommel, P F; Slappendel, E; Perquin, D; Smeenk, J M; Pelinck, M J; Gianotten, J; Hoozemans, D A; Maas, J W M; Eijkemans, M J C; van der Veen, F; Mol, B W J

2015-01-01

Objectives To compare the effectiveness of in vitro fertilisation with single embryo transfer or in vitro fertilisation in a modified natural cycle with that of intrauterine insemination with controlled ovarian hyperstimulation in terms of a healthy child. Design Multicentre, open label, three arm, parallel group, randomised controlled non-inferiority trial. Setting 17 centres in the Netherlands. Participants Couples seeking fertility treatment after at least 12 months of unprotected intercourse, with the female partner aged between 18 and 38 years, an unfavourable prognosis for natural conception, and a diagnosis of unexplained or mild male subfertility. Interventions Three cycles of in vitro fertilisation with single embryo transfer (plus subsequent cryocycles), six cycles of in vitro fertilisation in a modified natural cycle, or six cycles of intrauterine insemination with ovarian hyperstimulation within 12 months after randomisation. Main outcome measures The primary outcome was birth of a healthy child resulting from a singleton pregnancy conceived within 12 months after randomisation. Secondary outcomes were live birth, clinical pregnancy, ongoing pregnancy, multiple pregnancy, time to pregnancy, complications of pregnancy, and neonatal morbidity and mortality Results 602 couples were randomly assigned between January 2009 and February 2012; 201 were allocated to in vitro fertilisation with single embryo transfer, 194 to in vitro fertilisation in a modified natural cycle, and 207 to intrauterine insemination with controlled ovarian hyperstimulation. Birth of a healthy child occurred in 104 (52%) couples in the in vitro fertilisation with single embryo transfer group, 83 (43%) in the in vitro fertilisation in a modified natural cycle group, and 97 (47%) in the intrauterine insemination with controlled ovarian hyperstimulation group. This corresponds to a risk, relative to intrauterine insemination with ovarian hyperstimulation, of 1.10 (95% confidence interval 0.91 to 1.34) for in vitro fertilisation with single embryo transfer and 0.91 (0.73 to 1.14) for in vitro fertilisation in a modified natural cycle. These 95% confidence intervals do not extend below the predefined threshold of 0.69 for inferiority. Multiple pregnancy rates per ongoing pregnancy were 6% (7/121) after in vitro fertilisation with single embryo transfer, 5% (5/102) after in vitro fertilisation in a modified natural cycle, and 7% (8/119) after intrauterine insemination with ovarian hyperstimulation (one sided P=0.52 for in vitro fertilisation with single embryo transfer compared with intrauterine insemination with ovarian hyperstimulation; one sided P=0.33 for in vitro fertilisation in a modified natural cycle compared with intrauterine insemination with controlled ovarian hyperstimulation). Conclusions In vitro fertilisation with single embryo transfer and in vitro fertilisation in a modified natural cycle were non-inferior to intrauterine insemination with controlled ovarian hyperstimulation in terms of the birth of a healthy child and showed comparable, low multiple pregnancy rates. Trial registration Current Controlled Trials ISRCTN52843371; Nederlands Trial Register NTR939. PMID:25576320
Effect of initial seedling size, understory competition, and overstory density on the survival and growth of Pinus echinata seedlings underplanted in hardwood forests for restoration

Treesearch

John M. Kabrick; Benjamin O. Knapp; Daniel C. Dey; David R. Larsen

2015-01-01

There is interest in restoring shortleaf pine (Pinus echinata) in pineâoak woodlands where it once was abundant. Because of its shade intolerance and slow initial growth rate, shortleaf pine restoration has remained a challenge because competition from hardwoods exhibits greater initial growth following canopy removal but greater shade tolerance with...
Seedling establishment and physiological responses to temporal and spatial soil moisture changes

Treesearch

Jeremy Pinto; John D. Marshall; Kas Dumroese; Anthony S. Davis; Douglas R. Cobos

2016-01-01

In many forests of the world, the summer season (temporal element) brings drought conditions causing low soil moisture in the upper soil profile (spatial element) - a potentially large barrier to seedling establishment. We evaluated the relationship between initial seedling root depth, temporal and spatial changes in soil moisture during drought after...
Spatiotemporal dynamics of phosphorus release, oxygen consumption and greenhouse gas emissions after localised soil amendment with organic fertilisers.

PubMed

Christel, Wibke; Zhu, Kun; Hoefer, Christoph; Kreuzeder, Andreas; Santner, Jakob; Bruun, Sander; Magid, Jakob; Jensen, Lars Stoumann

2016-06-01

Organic fertilisation inevitably leads to heterogeneous distribution of organic matter and nutrients in soil, i.e. due to uneven surface spreading or inhomogeneous incorporation. The resulting localised hotspots of nutrient application will induce various biotic and abiotic nutrient turnover processes and fixation in the residue sphere, giving rise to distinct differences in nutrient availability, soil oxygen content and greenhouse gas (GHG) production. In this study we investigated the spatiotemporal dynamics of the reaction of manure solids and manure solids char with soil, focusing on their phosphorus (P) availability, as current emphasis on improving societal P efficiency through recycling waste or bio-based fertilisers necessitates a sound understanding of their behaviour. Soil layers amended at a constant P application rate with either pig manure solids or char made from pig manure solids were incubated for three weeks between layers of non-amended, P-depleted soil. Spatial and temporal changes in and around the amendment layers were simultaneously investigated in this study using a sandwich sensor consisting of a planar oxygen optode and multi-element diffusive gradients in thin films (DGT) gels, combined with GHG emission measurements. After three weeks of incubation, the soil containing a layer amended with manure solids had a lower overall O2 content and had emitted significantly more CO2 than the non-amended control or the char-amended soil. The P availability from manure solids was initially higher than that from the char, but decreased over time, whereas from the char-amended layer P availability increased in the same period. In both treatments, increases in P availability were confined to the amended soil layer and did not greatly affect P availability in the directly adjacent soil layers during the three-week incubation. These results highlight the importance of placing organic P fertilisers close to where the plant roots will grow in order to facilitate optimal fertiliser use efficiency. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.
Influence of family and nitrogen fertilizer on growth and nutrition of western hemlock seedlings.

Treesearch

M.A. Radwan; D.S. DeBell; J.E. Wilcox

1990-01-01

Effects of genotype and nitrogen fertilizer on growth and shoot nutrients of western hemlock seedlings were determined by using 11 open-pollinated families from coastal Oregon and Washington. The families differed significantly in growth, initially and after one growing season after treatment. All seedlings responded well to fertilizer, and fertilization significantly...
Ten-year growth comparison between rooted cuttings and seedlings of loblolly pine

Treesearch

H.E. Stelzer; G. Sam Foster; D.V. Shaw; J.B. McRae

1997-01-01

Rooted cuttings and seedlings of loblolly pine (Pinus taeda L.) were established in a central Alabama field trial. Five, full-sib families, with an average number of six clones per family, were evaluated. Mean cutting/seedling height ratios revealed that despite initial differences in size, relative growth rates of both propagule types stabilized and...
Underplanting cherrybark oak (Quercus pagoda Raf.) seedlings on a bottomland site in the southern United States

Treesearch

Emile S. Gardiner; Jimmie L. Yeiser

2006-01-01

We initiated a study on a bottomland site in the southern United States to examine the effects of Japanese honeysuckle (Lonicera japonica Thunberg) control and seedlings of two root classes on survival and growth of underplanted cherrybark oak (Quercus pagoda Raf.) seedlings. Three honeysuckle control treatments were assigned to...

Mosaic Stunting in jack pine seedlings in a northern Michigan bareroot nursery

Treesearch

Lynette Potvin; R. Kasten Dumroese; Martin F. Jurgensen; Dana Richter

2010-01-01

Mosaic, or patchy, stunting of bareroot conifer seedlings is thought to be caused by deficiencies of mycorrhizal fungi following fumigation, resulting in reduced nutrient uptake, particularly phosphorus. Mosaic stunting of jack pine (Pinus banksiana) seedlings was observed in 2005 at the USDA Forest Service JW Toumey Nursery in Watersmeet, MI. We initiated a study to...
Nursery response of Acacia koa seedlings to container size, irrigation method, and fertilization rate

Treesearch

R. Kasten Dumroese; Anthony S. Davis; Douglass F. Jacobs

2011-01-01

Planting koa (Acacia koa A. Gray) in Hawai'i, USA aids in restoration of disturbed sites essential to conservation of endemic species. Survival and growth of planted seedlings under vegetative competition typically increases with initial plant size. Increasing container size and fertilizer rate may produce larger seedlings, but high fertilization can lead to...
Phosphorus fertilisation under nitrogen limitation can deplete soil carbon stocks: evidence from Swedish meta-replicated long-term field experiments

NASA Astrophysics Data System (ADS)

Poeplau, Christopher; Bolinder, Martin A.; Kirchmann, Holger; Kätterer, Thomas

2016-02-01

Increasing soil organic carbon (SOC) in agricultural soils can mitigate atmospheric CO2 concentration and also contribute to increased soil fertility and ecosystem resilience. The role of major nutrients in SOC dynamics is complex, due to simultaneous effects on net primary productivity (NPP) that influence crop residue carbon inputs and in the rate of heterotrophic respiration (carbon outputs). This study investigated the effect on SOC stocks of three different levels of phosphorus and potassium (PK) fertilisation rates in the absence of nitrogen fertilisation and of three different levels of nitrogen fertiliser in the absence of PK fertiliser. This was done by analysing data from 10 meta-replicated Swedish long-term field experiments (> 45 years). With N fertilisation, SOC stocks followed yield increases. However, for all PK levels, we found average SOC losses ranging from -0.04 ± 0.09 Mg ha-1 yr-1 (ns) for the lowest to -0.09 ± 0.07 Mg ha-1 yr-1 (p = 0.008) for the highest application rate, while crop yields as a proxy for carbon input increased significantly with PK fertilisation by 1, 10 and 15 %. We conclude that SOC dynamics are mainly output-driven in the PK-fertilised regime but mostly input-driven in the N-fertilised regime, due to the much more pronounced response of NPP to N than to PK fertilisation. It has been established that P rather than K is the element affecting ecosystem carbon fluxes, where P fertilisation has been shown to (i) stimulate heterotrophic respiration, (ii) reduce the abundance of arbuscular mycorrhizal fungi and (iii) decrease the crop root : shoot ratio, leading to higher root-derived carbon input. The higher export of N in the PK-fertilised plots in this study could (iv) have led to increased N mining and thus mineralisation of organic matter. More integrated experiments are needed to gain a better understanding of the relative importance of each of the above-mentioned mechanisms leading to SOC losses after P addition.
Aspirin for in vitro fertilisation.

PubMed

Siristatidis, Charalambos S; Dodd, Susanna R; Drakeley, Andrew J

2011-08-10

Aspirin is used to improve the outcome in women undergoing in vitro fertilisation despite inconsistent evidence of its efficacy. The most appropriate time to commence aspirin therapy and the length of treatment required are also still to be determined. This is an update of the review first published in 2007. To determine the effectiveness and safety of aspirin for improving the outcome of in vitro fertilisation and intracytoplasmic sperm injection treatment cycles. We searched the Cochrane Menstrual Disorders and Subfertility Group Trials Register, Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library January 2011), MEDLINE (1966 to January 2011) and EMBASE (1980 to January 2011) databases. We used the research terms: "(aspirin OR acetylsalicylic acid) AND (in-vitro fertilisation OR intracytoplasmic sperm injection)", combined with the Cochrane Menstrual Disorders and Subfertility Group's search strategy, in order to identify randomised controlled trials on aspirin for women undergoing in vitro fertilisation. Randomised controlled trials. Two authors independently selected studies to include in the review, extracted data and assessed trial quality. The searches identified 13 trials which were eligible for inclusion in the review, including a total of 2653 participants. No significant differences were found between the treatment and control groups for any of the outcomes assessed. No significant differences were found in the meta-analysis of studies investigating the effect of aspirin compared with control on live birth rate (RR 0.91, 95% CI 0.72 to 1.15; three studies and 1053 participants), clinical pregnancy rate (RR 1.03, 95% CI 0.91 to 1.17; 10 studies and 2142 participants), ectopic and miscarriage rates (RR 1.86, 95% CI 0.75 to 4.63; RR 1.10, 95% CI 0.68 to 1.77) respectively (three and five studies involving 1135 and 1497 participants). Use of aspirin for women undergoing in vitro fertilisation cannot be recommended due to lack of evidence from the current trial data. Adequately powered trials are needed. It was proposed in the initial version of this review that a sample size of 350 women in each group would be required in order to demonstrate a 10% improvement from the use of aspirin, with 80% power at the 5% significance level. Until such evidence is available, this treatment can not be recommended.
Factors affecting acorn production and germination and early growth of seedlings and seedling sprouts

Treesearch

David F. Olson; Stephen G. Boyce

1971-01-01

Acorn production is extremely variable and unpredictable. Flowering is copious, but many climatic factors influence acorn development from initiation of flowers to acorn maturity. Acorns are consumed by birds, animals, insects, and microorganisms. The establishment of seedlings is more closely related to favorable site factors than to size of crops. A majority of oaks...
The influence of shade on northern red oak seedlings growth and carbon balance

Treesearch

Jennifer L. Jennings

1995-01-01

One management problem of the Southern Appalachian mixed hardwood forest is the lack of development of northern red oak (Quercus rubra L.) seedlings on high quality sites. Regeneration of red oak is not the problem. Following the removal of a stand, a combination of new seedlings, advanced reproduction and stump sprouts ensure red oak's initial...
Variation in flood tolerance of container-grown seedlings of swamp white oak, bur oak, and white oak

Treesearch

Michael P. Walsh; J.W. Van Sambeek; Mark V. Coggeshall

2008-01-01

How much variation in flood tolerance exists among seedlings within oak species, given the flood frequency of sites from which acorns are collected, has been largely unexplored. Our studies examined initial growth and flood tolerance for seedlings of swamp white oak (Quercus bicolor Willd.), bur oak (Q. macrocarpa L.), and white...
Perennial grasses reduce woody plant seedlings...on mixed conifer fuel-break

Treesearch

Harry E. Schimke Lisle R. Green Danny Heavilin

1970-01-01

After initial clearing, parts of a fuelbreak on the Stanislaus Nationd Forest, central California, were planted to perennial grasses; other parts were not. After 5 years, a comparison between adjacent seeded sand unseeded strips shows that the perernnials had reduced the number of woody plant seedlings by a factor of 8, height of seedlings by 50 percent, and amount of...
Influence of fertilisation regimes on a nosZ-containing denitrifying community in a rice paddy soil.

PubMed

Chen, Zhe; Hou, Haijun; Zheng, Yan; Qin, Hongling; Zhu, Yijun; Wu, Jinshui; Wei, Wenxue

2012-03-30

Denitrification is a microbial process that has received considerable attention during the past decade since it can result in losses of added nitrogen fertilisers from agricultural soils. Paddy soil has been known to have strong denitrifying activity, but the denitrifying microorganisms responsible for fertilisers in paddy soil are not well known. The objective of this study was to explore the impacts of 17-year application of inorganic and organic fertiliser (rice straw) on the abundance and composition of a nosZ-denitrifier community in paddy soil. Soil samples were collected from CK plots (no fertiliser), N (nitrogen fertiliser), NPK (nitrogen, phosphorus and potassium fertilisers) and NPK + OM (NPK plus organic matter). The nitrous oxide reductase gene (nosZ) community composition was analysed using terminal restriction fragment length polymorphism, and the abundance was determined by quantitative PCR. Both the largest abundance of nosZ-denitrifier and the highest potential denitrifying activity (PDA) occurred in the NPK + OM treatment with about four times higher than that in the CK and two times higher than that in the N and NPK treatments (no significant difference). Denitrifying community composition differed significantly among fertilisation treatments except for the comparison between CK and N treatments. Of the measured abiotic factors, total organic carbon was significantly correlated with the observed differences in community composition and abundance (P < 0.01 by Monte Carlo permutation). This study shows that the addition of different fertilisers affects the size and composition of the nosZ-denitrifier community in paddy soil. Copyright © 2011 Society of Chemical Industry.
Soil and pasture P concentration in a Fraxinus excelsior L. silvopastoral system fertilised with different types of sewage sludge

NASA Astrophysics Data System (ADS)

Ferreiro-Domínguez, Nuria; Nair, Vimala; Rigueiro-Rodríguez, Antonio; Rosa Mosquera-Losada, María

2015-04-01

In Europe, sewage sludge should be stabilised before using as fertiliser in agriculture. Depending on the stabilisation process that is used, sewage sludge has different characteristics, nutrient contents and soil nutrient incorporation rates. Sewage sludge is usually applied on a plant-available N or total metal concentration basic, and therefore, P concentrations can be well above crop needs. Leaching of excess P can threaten surface and ground waters with eutrophication. In this context, recent studies have demonstrated that the implementation of agroforestry systems could reduce the P leaching risk compared with conventional agricultural systems due to the different localisation of tree and crop roots which enhance nutrient uptake. The aim of this study was to evaluate during three consecutive years the effect of municipal sewage sludge stabilised by anaerobic digestion, composting, and pelletisation on concentration of P in soil and pasture compared to control treatments (mineral and no fertilisation) in a silvopastoral system established under Fraxinus excelsior L. in Galicia (Spain). The results showed that at the beginning of the study, the fertilisation with mineral increased more the total and available P in soil than the fertilisation with sewage sludge probably because the sludge nutrient release rate is slower than those from mineral fertilisers. The increment of soil available P caused by the mineral fertiliser implied an improvement of the P concentration in the pasture. However, in the last year of the experiment it was observed a positive effect of the fertilisation with pelletised sludge on the concentration of P in pasture compared with the composted sludge and the mineral fertiliser probably due to the annual application of this type of sludge. Therefore, the establishment of silvopastoral systems and their fertilisation with pelletized sludge should be recommended because the pelletized sludge increases the concentration of P in the pasture and reduces the application and storage costs due to its lower proportion of water than the other types of sludge tested. At the same time, the integration of trees in agricultural areas decreases the problem of environmental impact resulting from addition of organic and inorganic fertilisers on soils.
Trace element and nutrient accumulation in sunflower plants two years after the Aznalcóllar mine spill.

PubMed

Madejón, P; Murillo, J M; Marañón, T; Cabrera, F; Soriano, M A

2003-05-20

The failure of a tailing pond dam at the Aznalcóllar pyrite mine (SW Spain) in April 1998 released a toxic spill affecting approximately 4300 ha along the Agrio and Guadiamar valleys. Two years later, we have studied yield and concentration of mineral nutrients and trace elements in sunflower plants grown in the spill-affected soil, and in an adjacent unaffected soil as comparison. The study has been carried out in plants at seedling (V4) and mature (R8) stages. Shoot and root biomass of sunflower seedlings was significantly smaller in the affected soil than in the unaffected soil, but there was no significant difference at the mature stage. Oil production was greater in the spill-affected plants. We have not detected any 'fertilising' effect caused by the acid waters of the spill on the main nutrient (N, P and Ca) acquisition, as documented in 1998 for sunflower plants flooded by the spill. Sunflower plants growing in the spill-affected soil reached adequate levels of nutrients. None of the trace elements measured-As, Cd, Cu, Pb and Tl-reached levels either phytotoxic or toxic for humans or animals in seeds and the above-ground part of the spill-affected plants. We evaluate the potential use of sunflower plants for phytoremediation. The potential for phytoextraction is very low; however, it may be used for soil conservation. The production of oil (usable for industrial purposes) may add some value to this crop.
DNA Damage Levels Determine Cyclobutyl Pyrimidine Dimer Repair Mechanisms in Alfalfa Seedlings.

PubMed Central

Quaite, F. E.; Takayanagi, S.; Ruffini, J.; Sutherland, J. C.; Sutherland, B. M.

1994-01-01

Ultraviolet radiation in sunlight damages DNA in plants, but little is understood about the types, lesion capacity, and coordination of repair pathways. We challenged intact alfalfa seedlings with UV doses that induced different initial levels of cyclobutyl pyrimidine dimers and measured repair by excision and photoreactivation. By using alkaline gel electrophoresis of nonradioactive DNAs treated with a cyclobutyl pyrimidine dimer-specific UV endonuclease, we quantitated ethidium-stained DNA by electronic imaging and calculated lesion frequencies from the number average molecular lengths. At low initial dimer frequencies (less than ~30 dimers per million bases), the seedlings used only photoreactivation to repair dimers; excision repair was not significant. At higher damage levels, both excision and photorepair contributed significantly. This strategy would allow plants with low damage levels to use error-free repair requiring only an external light energy source, whereas seedlings subjected to higher damage frequencies could call on additional repair processes requiring cellular energy. Characterization of repair in plants thus requires an investigation of a range of conditions, including the level of initial damage. PMID:12244228
Implications of seed size for seedling survival in Carnegiea gigantea and Ferocactus wislizeni (Cactaceae)

USGS Publications Warehouse

Bowers, Janice E.; Pierson, E.A.

2001-01-01

Larger seeds have been shown to convey benefits for seedling survival but the mechanisms of this process are not well understood. In this study, seed size and seedling survival were compared for 2 sympatric cactus species, Carnegiea gigantea (Engelm.) Britt. & Rose and Ferocactus wislizeni (Engelm.) Britt. & Rose, in laboratory and field experiments in the northern Sonoran Desert. Both species have small seeds, but Ferocactus seeds are nearly twice as long and 3 times as heavy as those of Carnegiea. The difference in size is perpetuated after germination: new Ferocactus seedlings have 4 times the estimated volume of new Carnegiea seedlings. In an outdoor experiment, annual survivorship of both species was low but was 6 times higher for Ferocactus (6 seedlings, 8.1%) than Carnegiea (1 seedling, 1.4%). The pattern of seedling mortality in relation to temperature and rain suggests that, after the initial flush of seed and seedling predation, drought and heat took a greater toll on Carnegiea than Ferocactus seedlings, probably because the larger seedling volume of Ferocactus conferred greater drought tolerance. In addition, F. wislizeni could become established without benefit of nurse plants whereas C. gigantea could not; this might reflect differential tolerance to high soil temperatures.
Calcium-sensing receptor (CASR) is involved in porcine in vitro fertilisation and early embryo development.

PubMed

Liu, C; Liu, Y; Larsen, K; Hou, Y P; Callesen, H

2018-01-01

It has been demonstrated that extracellular calcium is necessary in fertilisation and embryo development but the mechanism is still not well understood. The present study mainly focussed on the extracellular calcium effector called the calcium-sensing receptor (CASR) and examined its expression in porcine gametes and embryos and its function during fertilisation and early embryo development. By using reverse transcription polymerase chain reaction, CASR was found to be expressed in porcine oocytes, spermatozoa and embryos at different developmental stages. Functionally, medium supplementation with a CASR agonist or an antagonist during in vitro fertilisation (IVF) and in vitro culture (IVC) was tested. During fertilisation, the presence of a CASR agonist increased sperm penetration rate and decreased polyspermy rate leading to an increased normal fertilisation rate. During embryo development, for the IVF embryos, agonist treatment during IVC significantly increased cleavage rate and blastocyst formation rate compared with the control group. Furthermore, parthenogenetically activated embryos showed similar results with lower cleavage and blastocyst formation rates in the antagonist group than in the other groups. It was concluded that CASR, as the effector of extracellular calcium, modulates porcine fertilisation and early embryo development.
Pure human urine is a good fertiliser for cucumbers.

PubMed

Heinonen-Tanski, Helvi; Sjöblom, Annalena; Fabritius, Helena; Karinen, Päivi

2007-01-01

Human urine obtained from separating toilets was tested as a fertiliser for cultivation of outdoor cucumber (Cucumis sativus L.) in a Nordic climate. The urine used contained high amounts of nitrogen with some phosphorus and potassium, but numbers of enteric microorganisms were low even though urine had not been preserved before sampling. The cucumber yield after urine fertilisation was similar or slightly better than the yield obtained from control rows fertilised with commercial mineral fertiliser. None of the cucumbers contained any enteric microorganisms (coliforms, enterococci, coliphages and clostridia). In the taste assessment, 11 out of 20 persons could recognise which cucumber of three cucumbers was different but they did not prefer one over the other cucumber samples, since all of them were assessed as equally good.
Drying or anaerobic digestion of fish sludge: Nitrogen fertilisation effects and logistics.

PubMed

Brod, Eva; Oppen, Johan; Kristoffersen, Annbjørg Øverli; Haraldsen, Trond Knapp; Krogstad, Tore

2017-12-01

Application of fish sludge as fertiliser to agricultural land can contribute to closing nutrient cycles in fish farming. The effect of different treatment technologies on the nitrogen fertilisation effects of fish sludge was studied by a bioassay with barley (Hordeum vulgare), an incubation and a field experiment. Dried fish sludge resulted in relative agronomic efficiency of 50-80% compared with mineral fertiliser. The anaerobic digestate based on fish sludge (20 vol%) and dairy manure did not increase nitrogen uptake in barley. Increasing the ratio of fish sludge in the digestate increased the fertilisation effect, but requires optimisation of the biogas process. A simple logistics analysis conducted for a case hatchery showed that on-site drying and co-digestion of fish sludge in a central biogas plant can be regarded as equal in terms of costs. Norway can become an exporter of fish sludge-based recycling fertilisers if current regulations are modified to facilitate nutrient recycling.
Chlorophyll, Carotenoid and Anthocyanin Accumulation in Mung Bean Seedling Under Clinorotation

NASA Astrophysics Data System (ADS)

Nakajima, Shusaku; Shiraga, Keiichiro; Suzuki, Tetsuhito; Kondo, Naoshi; Ogawa, Yuichi

2017-12-01

The accumulation of plant pigments in mung bean ( Vigna radiata L.) seedlings was measured after clinorotation (2 rpm for 2-4 days), and compared to a stationary control. The pigments measured included chlorophyll and carotenoid in primary leaves, and the anthocyanin in seedlings. While significant changes in chlorophyll and carotenoid accumulation were not observed during the initial 2 to 4 days of cultivation, by day 4 the seedlings grown on the clinostat had lower levels of anthocyanin, compared to those in the control seedlings. To further detail the cause for the observed reduction in anthocyanin accumulation under altered gravity conditions, seedlings were grown in the presence of silver nitrate, a known ethylene inhibitor, for 4 days, since it is known ethylene has a negative impact on anthocyanin accumulation. Silver nitrate promoted anthocyanin accumulation in the clinostat seedlings, and as a result there was no significant difference between the control and clinostat seedlings in anthocyanin accumulation. The results suggest that slow clinorotation negatively impacts anthocyanin pigmentation in mung bean seedlings, with endogenous ethylene suspected to be involved in this.
Fluorescent sperm offer a method for tracking the real-time success of ejaculates when they compete to fertilise eggs.

PubMed

Lymbery, Rowan A; Kennington, W Jason; Evans, Jonathan P

2016-03-04

Despite intensive research effort, many uncertainties remain in the field of gamete-level sexual selection, particularly in understanding how sperm from different males interact when competing for fertilisations. Here, we demonstrate the utility of broadcast spawning marine invertebrates for unravelling these mysteries, highlighting their mode of reproduction and, in some species, unusual patterns of mitochondrial inheritance. We present a method utilising both properties in the blue mussel, Mytilus galloprovincialis. In mytilids and many other bivalves, both sperm and egg mitochondria are inherited. We exploit this, using the vital mitochondrial dye MitoTracker, to track the success of sperm from individual males when they compete with those from rivals to fertilise eggs. We confirm that dying mitochondria has no adverse effects on in vitro measures of sperm motility (reflecting mitochondrial energetics) or sperm competitive fertilisation success. Therefore, we propose the technique as a powerful and logistically tractable tool for sperm competition studies. Importantly, our method allows the competitive fertilisation success of sperm from any male to be measured directly and disentangled from confounding effects of post-fertilisation embryo survival. Moreover, the mitochondrial dye has broader applications in taxa without paternal mitochondrial inheritance, for example by tracking the dynamics of competing ejaculates prior to fertilisation.
Fluorescent sperm offer a method for tracking the real-time success of ejaculates when they compete to fertilise eggs

PubMed Central

Lymbery, Rowan A.; Kennington, W. Jason; Evans, Jonathan P.

2016-01-01

Despite intensive research effort, many uncertainties remain in the field of gamete-level sexual selection, particularly in understanding how sperm from different males interact when competing for fertilisations. Here, we demonstrate the utility of broadcast spawning marine invertebrates for unravelling these mysteries, highlighting their mode of reproduction and, in some species, unusual patterns of mitochondrial inheritance. We present a method utilising both properties in the blue mussel, Mytilus galloprovincialis. In mytilids and many other bivalves, both sperm and egg mitochondria are inherited. We exploit this, using the vital mitochondrial dye MitoTracker, to track the success of sperm from individual males when they compete with those from rivals to fertilise eggs. We confirm that dying mitochondria has no adverse effects on in vitro measures of sperm motility (reflecting mitochondrial energetics) or sperm competitive fertilisation success. Therefore, we propose the technique as a powerful and logistically tractable tool for sperm competition studies. Importantly, our method allows the competitive fertilisation success of sperm from any male to be measured directly and disentangled from confounding effects of post-fertilisation embryo survival. Moreover, the mitochondrial dye has broader applications in taxa without paternal mitochondrial inheritance, for example by tracking the dynamics of competing ejaculates prior to fertilisation. PMID:26941059
Determining the need for rescue intracytoplasmic sperm injection in partial fertilisation failure during a conventional IVF cycle.

PubMed

Cao, S; Wu, X; Zhao, C; Zhou, L; Zhang, J; Ling, X

2016-12-01

To explore the need for rescue intracytoplasmic sperm injection (ICSI) in cases of partial fertilisation failure during a conventional in vitro fertilisation cycle, rescue ICSI was performed for cycles with a fertilisation rate of <50%. The data were divided into three groups based on the fertilisation rate: group 1 (0%), group 2 (<25%) and group 3 (>25%). The impact of rescue ICSI on each group was then analysed in terms of ovum fertilisation, embryo development, embryo utilisation and selection of embryos for transfer. Rescue ICSI was performed on 1831 unfertilised oocytes from 313 cycles. The fertilisation rates for group 1, group 2 and group 3 were 74.66, 68.35 and 65.46%, and the rate of polyploidy in the three groups was 8.55, 11.33, and 14.47%. The percentage of embryos that can be transferred from rescue ICSI for group 2 was 38.33%, and this value was higher than those of the other two groups. It is concluded that rescue ICSI is not recommended for patients with an IVF rate of >25% as the procedure is associated with a greater risk and low returns. However, it is feasible to perform rescue ICSI for patients with IVF rates of <25%. © 2016 Blackwell Verlag GmbH.

Effect of ponderosa pine needle litter on grass seedling survival.

Treesearch

Burt R. McConnell; Justin G. Smith

1971-01-01

Hard fescue survival rates were followed for 6 years on four different pine needle treatment plots. Needle litter had a significant effect on initial survival of fescue seedlings, but subsequent losses undoubtedly resulted from the interaction of many factors.
Effect Of Seedling Size And First-Order Lateral Roots On Early Development Of Northern Red Oak On A Mesic Site: Eleventh-Year Results

Treesearch

Paul P. Kormanik; Shi-Jean S. Sung; Donald Kass; Stanley J. Zarnoch

2002-01-01

Abstract - The effect of initial first-order lateral root (FOLR) groupings of northern red oak (Quercus rubra) seedlings on a high quality mesic site was followed for eleven years on a shelterwood and a clearcut area. The initial FOLR number groups were empirically determined as low (0 to 6) medium (7 to 12) and high (12). The...
The influence of testicular microlithiasis on the outcomes of in vitro fertilisation in a Chinese Han population.

PubMed

Xu, C; Zhang, F-F; Yang, H-L; Ma, G; Zhang, B; Li, K-J; Zhang, T-J; Liu, J-L; Xuan, X-J

2017-10-01

To investigate the influence of testicular microlithiasis (TM) on the outcomes of in vitro fertilisation (IVF), we retrospectively reviewed the ultrasonography results of the TM patients who underwent IVF treatment in our hospital. They were classified as classic-TM (CTM) or limited-TM (LTM) comparing with patients without TM (Non-TM). Semen parameters, rates of fertilisation, normal fertilisation, good embryos and clinical pregnancy were analysed. The Non-TM group showed higher percentage of morphologically normal spermatozoa than the CTM or LTM group (4.08 ± 2.07 versus 3.40 ± 2.00 versus 3.04 ± 1.66, p = .003) while the other general semen parameters were comparable. The LTM group showed higher rate of fertilisation than the CTM group (85.10% versus 81.12%, p = .044). Moreover, the rates of normal fertilisation of Non-TM (62.47%) and LTM (66.32%) group were significantly higher than the CTM (58.02%) group (p = .027 and p = .001 respectively). There were 333 embryo transfer cycles in total (including 222 fresh and 111 frozen). The overall clinical pregnancy rate was 54.95%, 58.33% and 64.12% in the group of CTM, LTM and Non-TM respectively. However, no statistically significant difference was obtained (p = .326). Our results suggest that TM may have influence on the IVF outcomes. The extent of microlithiasis correlates inversely with the rates of fertilisation and normal fertilisation. © 2016 Blackwell Verlag GmbH.
Survey on nutrient content of different organic fertilisers.

PubMed

Rajan, Jagadish; Anandhan, Shanmugaselvan Veilumuthu

2015-06-01

The knowledge of nutrient aspects of organic fertilisers is of much relevance in assessing their availability and long-term effect to the soil and crop and in formulating sound fertiliser recommendation. Around 619 organic fertiliser samples under different categories, which were received by the analytical laboratory of UPASI Tea Research Institute, Valparai, were examined for their nutrient status. The trend in the number of samples received every year for the past 5 years showed that there is a gradual, steady and linear increase in the number of samples received by the laboratory which, in turn, authenticates the increase in the production and utilisation of organic fertilisers in agricultural sector. This also reveals the awareness of organic farming among farmers in recent times. The organic fertilisers received by the laboratory were categorised into different groups based on their nomenclature. The number of samples received each year under different categories varies to a larger extent. The nutritional status was unpredictable based on the nomenclature of the sample received. In addition to this frequency distribution, the nutritional values analysed are discussed in this paper. Correlation matrix was worked out between all the parameters estimated. It is evident that if maintenance of proper carbon-to-nitrogen ratio and moisture content is ascertained in the finished product, one can guarantee the quality of the organic fertiliser in terms of nutrient content.
Effect of nitrogen fertilisation on the amino acid digestibility of different triticale genotypes in caecectomised laying hens.

PubMed

Siegert, Wolfgang; Boguhn, Jeannette; Maurer, Hans Peter; Weiss, Jochen; Zuber, Tobias; Möhring, Jens; Rodehutscord, Markus

2017-01-01

The influence of nitrogen fertilisation and genotype on the amino acid (AA) digestibility of triticale grain was investigated in caecectomised laying hens. Three genotypes, Grenado, EAW6002 and Lasko, were cultivated with and without nitrogen fertilisation at the end of the heading stage. The six triticale variants as well as a basal diet were each used to feed seven laying hens in a 7 × 7 Latin square design. Nitrogen fertilisation influenced the digestibility of Cys, Glu, Phe and Ser in some triticale genotypes and reduced Ala, Ile, Lys, Met and Val digestibility in all genotypes (P < 0.05). Nitrogen fertilisation increased the concentration of all AAs in the grain. Consequently, the concentration of digestible AAs in the grains was increased for most AAs upon nitrogen fertilisation. Overall, Lys had the lowest digestibility, whereas that of Glu and Pro was the highest. For the triticale genotypes, the level of AA digestibility was highest for EAW6002 followed by Lasko and Grenado, with significant differences (P < 0.05) between genotypes for some but not all AAs. The results indicated that the accuracy of the digestible AA supply for hen feeding might benefit from considering fertilisation and genotype-specific digestibility data in feed formulation. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.
Uptake of pharmaceuticals by sorbent-amended struvite fertilisers recovered from human urine and their bioaccumulation in tomato fruit.

PubMed

de Boer, Marissa A; Hammerton, Michelle; Slootweg, J Chris

2018-04-15

Struvite precipitation is a well-documented method for recovering up to 98% of phosphorus from urine, which is one of the main nutrients in fertilizers besides nitrogen and potassium. Shortcomings of this process, however, are the low nitrogen recovery ratio and the possible uptake of pharmaceuticals from urine. In this work, the NH 4 + adsorbent materials biochar and zeolite are coupled with struvite precipitation to increase the N-recovery of struvite from 5.7% to 9.8%. Since nitrogen is one of the main nutrients in fertilisers, this increase is of significance for its potential commercial use. In addition, urine is spiked with pharmaceuticals to measure the consequential uptake in struvite-based fertilisers and crops afterwards. Five fertilisers are prepared by nutrient recovery from spiked urine using: (1) struvite crystallisation, (2) struvite crystallisation combined with N adsorption on zeolite, (3) struvite crystallisation combined with N adsorption on biochar, (4) N adsorption on zeolite without struvite crystallisation, and (5) N adsorption on biochar without struvite crystallisation. The fertiliser with the highest purity product and the lowest uptake of pharmaceuticals was struvite combined with zeolite. Next, the contaminated struvite-sorbent fertilisers are tested in a crop trial in which the bioaccumulation of pharmaceuticals in edible plant tissue (tomatoes) is measured. This bioaccumulation in tomato fruit biomass from each of the spiked fertilisers in the crop trial was found to be lower than 0.0003% in all cases, far below the acceptable daily intake (ADI) levels (750 kg of dry tomatoes should be consumed per day to reach the ADI limit). Consequently, the subsequent risk to human health from tomato fruit grown using urine derived struvite-sorbent fertilisers is found to be insignificant. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.
Mouse oocytes fertilised by ICSI during in vitro maturation retain the ability to be activated after refertilisation in metaphase II and can generate Ca2+ oscillations

PubMed Central

Jędrusik, Agnieszka; Ajduk, Anna; Pomorski, Paweł; Maleszewski, Marek

2007-01-01

Background At fertilisation, mammalian oocytes are activated by oscillations of intracellular Ca2+ ([Ca2+]i). Phospholipase Cζ, which is introduced by fertilising spermatozoon, triggers [Ca2+]i oscillations through the generation of inositol 1,4,5-triphosphate (IP3), which causes Ca2+ release by binding to IP3 receptors located on the endoplasmic reticulum (ER) of the oocyte. Ability to respond to this activating stimulus develops during meiotic maturation of the oocyte. Here we examine how the development of this ability is perturbed when a single spermatozoon is introduced into the oocyte prematurely, i.e. during oocyte maturation. Results Mouse oocytes during maturation in vitro were fertilised by ICSI (intracytoplasmic sperm injection) 1 – 4 h after germinal vesicle break-down (GVBD) and were subsequently cultured until they reached metaphase II (MII) stage. At MII stage they were fertilised in vitro for the second time (refertilisation). We observed that refertilised oocytes underwent activation with similar frequency as control oocytes, which also went through maturation in vitro, but were fertilised only once at MII stage (87% and 93%, respectively). Refertilised MII oocytes were able to develop [Ca2+]i oscillations in response to penetration by spermatozoa. We found however, that they generated a lower number of transients than control oocytes. We also showed that the oocytes, which were fertilised during maturation had a similar level of MPF activity as control oocytes, which were not subjected to ICSI during maturation, but had reduced level of IP3 receptors. Conclusion Mouse oocytes, which were experimentally fertilised during maturation retain the ability to generate repetitive [Ca2+]i transients, and to be activated after completion of maturation. PMID:17584490
Correlation analysis of the progesterone-induced sperm acrosome reaction rate and the fertilisation rate in vitro.

PubMed

Jiang, T; Qin, Y; Ye, T; Wang, Y; Pan, J; Zhu, Y; Duan, L; Li, K; Teng, X

2015-10-01

In this study, we aimed to investigate whether progesterone-induced acrosome reaction (AR) rate could be an indicator for fertilisation rate in vitro. Twenty-six couples with unexplained infertility and undergoing in vitro fertilisation (IVF) treatment were involved. On the oocytes retrieval day after routine IVF, residual sperm samples were collected to receive progesterone induction (progesterone group) or not (control group). AR rate was calculated and fertilisation rate was recorded. The correlation between progesterone-induced AR and fertilisation rate and between sperm normal morphology and 3PN (tripronuclear) were analysed using the Spearman correlation analysis. The AR rate of progesterone group was statistically higher than that of the control group (15.6 ± 5.88% versus 9.66 ± 5.771%, P < 0.05), but not significantly correlated with fertilisation rate (r = -0.053, P > 0.01) or rate of high-quality embryo development (r = -0.055, P > 0.01). Normal sperm morphology also showed no significant correlation with the amount of 3PN zygotes (r = 0.029, P > 0.01), rate of 3PN zygotes production (r = 0.20, P > 0.01), rate of 3PN embryo development (r = -0.406, P > 0.01), fertilisation rate (r = -0.148, P > 0.01) or progesterone-induced AR rate (r = 0.214, P > 0.01). Progesterone can induce AR in vitro significantly; however, the progesterone-induced AR may not be used to indicate fertilisation rate. © 2014 Blackwell Verlag GmbH.
Effect of vegetation management for reducing damage to lodgepole pine seedlings from northern pocket gophers

USGS Publications Warehouse

Engeman, Richard M.; Barnes, Victor G.; Anthony, Richard M.; Krupa, Heather W.

1997-01-01

The effects of vegetation management on northern pocket gopher (Thomomys talpoides) activity and damage to lodgepole pine (Pinus contorta) seedlings were studied using 2,4-D herbicide to alter the habitat. Treatments were applied to a large (8.1 ha) treatment unit and observed effects were compared with an untreated control unit of the same size. The greatly reduced forb and grass cover on the treated unit was associated with a corresponding decrease in pocket gopher activity that persisted for 6 years after initial treatment. Times until seedlings first incurred gopher damage and overall survival of seedlings were greatly increased on the treated unit.
Invasibility of a nutrient-poor pasture through resident and non-resident herbs is controlled by litter, gap size and propagule pressure.

PubMed

Eckstein, R Lutz; Ruch, Diana; Otte, Annette; Donath, Tobias W

2012-01-01

Since inference concerning the relative effects of propagule pressure, biotic interactions, site conditions and species traits on the invasibility of plant communities is limited, we carried out a field experiment to study the role of these factors for absolute and relative seedling emergence in three resident and three non-resident confamilial herb species on a nutrient-poor temperate pasture. We set up a factorial field experiment with two levels each of the factors litter cover (0 and 400 g m(-2)), gap size (0.01 and 0.1 m(2)) and propagule pressure (5 and 50 seeds) and documented soil temperature, soil water content and relative light availability. Recruitment was recorded in spring and autumn 2010 and in spring 2011 to cover initial seedling emergence, establishment after summer drought and final establishment after the first winter. Litter alleviated temperature and moisture conditions and had positive effects on proportional and absolute seedling emergence during all phases of recruitment. Large gaps presented competition-free space with high light availability but showed higher temperature amplitudes and lower soil moisture. Proportional and absolute seedling recruitment was significantly higher in large than in small gaps. In contrast, propagule pressure facilitated absolute seedling emergence but had no effects on proportional emergence or the chance for successful colonisation. Despite significantly higher initial seedling emergence of resident than non-resident species, seed mass and other species-specific traits may be better predictors for idiosyncratic variation in seedling establishment than status. Our data support the fluctuating resource hypothesis and demonstrate that the reserve effect of seeds may facilitate seedling emergence. The direct comparison of propagule pressure with other environmental factors showed that propagule pressure affects absolute seedling abundance, which may be crucial for species that depend on other individuals for sexual reproduction. However, propagule batch size did not significantly affect the chance for successful colonisation of disturbed plots.
Sensitivity of salad greens (Lactuca sativa L. and Eruca sativa Mill.) exposed to crude extracts of toxic and non-toxic cyanobacteria.

PubMed

Bittencourt-Oliveira, M C; Hereman, T C; Macedo-Silva, I; Cordeiro-Araújo, M K; Sasaki, F F C; Dias, C T S

2015-05-01

We evaluated the effect of crude extracts of the microcystin-producing (MC+) cyanobacteria Microcystis aeruginosa on seed germination and initial development of lettuce and arugula, at concentrations between 0.5 μg.L(-1) and 100 μg.L(-1) of MC-LR equivalent, and compared it to crude extracts of the same species without the toxin (MC-). Crude extracts of the cyanobacteria with MC (+) and without MC (-) caused different effects on seed germination and initial development of the salad green seedlings, lettuce being more sensitive to both extracts when compared to arugula. Crude extracts of M. aeruginosa (MC+) caused more evident effects on seed germination and initial development of both species of salad greens than MC-. Concentrations of 75 μg.L(-1) and 100 μg.L(-1) of MC-LR equivalent induced a greater occurrence of abnormal seedlings in lettuce, due to necrosis of the radicle and shortening of this organ in normal seedlings, as well as the reduction in total chlorophyll content and increase in the activity of the antioxidant enzyme peroxidase (POD). The MC- extract caused no harmful effects to seed germination and initial development of seedlings of arugula. However, in lettuce, it caused elevation of POD enzyme activity, decrease in seed germination at concentrations of 75 μg.L(-1) (MC-75) and 100 μg.L(-1) (MC-100), and shortening of the radicle length, suggesting that other compounds present in the cyanobacteria extracts contributed to this result. Crude extracts of M. aeruginosa (MC-) may contain other compounds, besides the cyanotoxins, capable of causing inhibitory or stimulatory effects on seed germination and initial development of salad green seedlings. Arugula was more sensitive to the crude extracts of M. aeruginosa (MC+) and (MC-) and to other possible compounds produced by the cyanobacteria.
Sequential analysis of sperm functional aspects involved in fertilisation: a pilot study.

PubMed

Abu, D A H; Franken, D R; Hoffman, B; Henkel, R

2012-05-01

The development of diagnostic techniques in andrology as a second level of approach to the diagnosis of male factor infertility has enthused the focus of researchers on the development of a sequential diagnostic programme for these men. Semen samples of 78 men form couples undergoing in vitro fertilisation therapy were used in the study. The semen samples were used to test sperm functional aspects known to interfere with fertilisation. These tests included semen profile, DNA integrity, apoptosis, chromatin packaging, acridin orange staining, zona binding capacity, zona-induced acrosome reaction (AR). Results were correlated with fertilisation outcome. Statistical analyses of the recorded data were carried out using a logistic regression analysis model on all sperm functional tests. A negative and significant association with the fertilisation rates was recorded for DNA damage (r = -0.56; P ≤ 0.0005). A positive significant correlation was recorded between fertilisation rates and sperm with normal DNA (r = -0.57, P ≤ 0.0004), and zona-induced AR (r = 0.33, P ≤ 0.002). Diagnostic andrology can be regarded as a mandatory part of the male factor patient's work-up schedule to assist clinicians with the most suitable therapeutic modality to follow. © 2011 Blackwell Verlag GmbH.
The surprisingly small but increasing role of international agricultural trade on the European Union’s dependence on mineral phosphorus fertiliser

NASA Astrophysics Data System (ADS)

Nesme, Thomas; Roques, Solène; Metson, Geneviève S.; Bennett, Elena M.

2016-02-01

Phosphorus (P) is subject to global management challenges due to its importance to both food security and water quality. The European Union (EU) has promoted policies to limit fertiliser over-application and protect water quality for more than 20 years, helping to reduce European P use. Over this time period, the EU has, however, become more reliant on imported agricultural products. These imported products require fertiliser to be used in distant countries to grow crops that will ultimately feed European people and livestock. As such, these imports represent a displacement of European P demand, possibly allowing Europe to decrease its apparent P footprint by moving P use to locations outside the EU. We investigated the effect of EU imports on the European P fertiliser footprint to better understand whether the EU’s decrease in fertiliser use over time resulted from P demand being ‘outsourced’ to other countries or whether it truly represented a decline in P demand. To do this, we quantified the ‘virtual P flow’ defined as the amount of mineral P fertiliser applied to agricultural soils in non-EU countries to support agricultural product imports to the EU. We found that the EU imported a virtual P flow of 0.55 Tg P/yr in 1995 that, surprisingly, decreased to 0.50 Tg P/yr in 2009. These results were contrary to our hypothesis that trade increases would be used to help the EU reduce its domestic P fertiliser use by outsourcing its P footprint abroad. Still, the contribution of virtual P flows to the total P footprint of the EU has increased by 40% from 1995 to 2009 due to a dramatic decrease in domestic P fertiliser use in Europe: in 1995, virtual P was equivalent to 32% of the P used as fertiliser domestically to support domestic consumption but jumped to 53% in 2009. Soybean and palm tree products from South America and South East Asia contributed most to the virtual P flow. These results demonstrate that, although policies in the EU have successfully decreased the domestic dependence on mineral P fertiliser, in order to continue to limit global potential mineral P supply depletion and consequences of P losses to waterways the EU may have to think about its trading partners.
Bacterial stimulation of adventitious rooting on in vitro cultured slash pine (Pinus elliottii Engelm.) seedling explants.

PubMed

Burns, J A; Schwarz, O J

1996-02-01

A bacterium has been isolated that initiates adventitious rooting when co-cultured under in vitro conditions with seedling-produced hypocotylary explants of slash pine (Pinus elliottii). Rooting efficiencies produced through bacterial-explant co-culture range from approximately 15% to greater than 90% over non-treated controls. Explant exposure to the root inducing bacterium has produced no obvious pathology in the regenerated plantlets. Seedling explants rooted by bacterial-explant co-culture have been successfully transitioned to ambient greenhouse conditions.
Activity concentrations of ²²⁶Ra, ²³²Th and ⁴⁰K in brands of fertilisers used in Nigeria.

PubMed

Jibiri, N N; Fasae, K P

2012-01-01

The activity concentration of naturally occurring radionuclides ⁴⁰K, ²²⁶Ra and ²³²Th have been measured in different brands of fertiliser samples sold to farmers in retail markets in six commercial cities in southwestern Nigeria. Gamma ray spectroscopy was employed in the measurements of these radionuclides. The results of measurements showed that the average activity concentration of ⁴⁰K in the nitrogen, phosphorus and potassium fertilisers across the cities varied from 3972.0 ± 416.9 to 5089.3 ± 111.3 Bq kg⁻¹, 9.9 ± 7.3 to 450.6 ± 14.3 Bq kg⁻¹ for ²²⁶Ra, while for ²³²Th it varied from less than lower limit of detection to 15.1 ± 2.8 Bq kg⁻¹. The activity concentrations of ⁴⁰K, ²²⁶Ra and ²³²Th in single super phosphate (SSP) fertilisers and phosphate rocks were also determined. However, high activity concentrations of ²²⁶Ra were obtained in the SSP fertiliser and phosphate rocks and in particular, two brands of fertilisers from ITL/TAK and F & C companies. The values of the activity concentration of the radionuclides in the brands of fertilisers used in Nigeria are within the range of values reported in several other countries except ⁴⁰K.
Germination Under Stress: A Marker For Inherent Vigor Or An Isolated Event?

USDA-ARS?s Scientific Manuscript database

Seedling vigor and its translation to late-season vigor are, at best, murky for most beet breeders. The initial conditions a germinating seed encounters, and its ability to overcome them, affects stored energy reserves to withstand future adverse environments and the ability of the seedling to survi...
Seedling Vigor in Beta vulgaris: The Artistry of Germination

USDA-ARS?s Scientific Manuscript database

Seedling vigor and stand establishment are two problems that growers have struggled with for decades. The initial conditions that a germinating seed encounters, and its ability to deal with them, affect the rate at which germination occurs, the rate of mobilization of stored energy reserves that the...
Effects of nursery fertilizer and irrigation on ponderosa and lodgepole pine seedling size. Forest Service research note

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sloan, J.P.

1992-12-01

Eight fertilizer treatments combined with three irrigation regimes were used when growing lodgepole and ponderosa pine seedlings on two soil types at Lucky Peak Nursery near Biose, ID. Seedlings of both species were larger on the sandy loam than the clay loam soil. Milorganite, an organic fertilizer derived from sewage sludge, reduced initial seedbeed densities but had no further effects. Ammonium nitrate increased seedling size on the clay loam, but not on the sandy loam soil. Increased irrigation was more effective in increasing seedling size on the sandy loam than on the clay loam soil. However, ponderosa pine receiving themore » least irrigation in the nursery grew the fastest for 3 years after being transplanted in the field, possibly because of drought conditioning.« less
Effects of nitrogen fertilisation rate and maturity of grass silage on methane emission by lactating dairy cows.

PubMed

Warner, D; Hatew, B; Podesta, S C; Klop, G; van Gastelen, S; van Laar, H; Dijkstra, J; Bannink, A

2016-01-01

Grass silage is typically fed to dairy cows in temperate regions. However, in vivo information on methane (CH(4)) emission from grass silage of varying quality is limited. We evaluated the effect of two rates of nitrogen (N) fertilisation of grassland (low fertilisation (LF), 65 kg of N/ha; and high fertilisation (HF), 150 kg of N/ha) and of three stages of maturity of grass at cutting: early maturity (EM; 28 days of regrowth), mid maturity (MM; 41 days of regrowth) and late maturity (LM; 62 days of regrowth) on CH(4) production by lactating dairy cows. In a randomised block design, 54 lactating Holstein-Friesian dairy cows (168±11 days in milk; mean±standard error of mean) received grass silage (mainly ryegrass) and compound feed at 80 : 20 on dry matter basis. Cows were adapted to the diet for 12 days and CH(4) production was measured in climate respiration chambers for 5 days. Dry matter intake (DMI; 14.9±0.56 kg/day) decreased with increasing N fertilisation and grass maturity. Production of fat- and protein-corrected milk (FPCM; 24.0±1.57 kg/day) decreased with advancing grass maturity but was not affected by N fertilisation. Apparent total-tract feed digestibility decreased with advancing grass maturity but was unaffected by N fertilisation except for an increase and decrease in N and fat digestibility with increasing N fertilisation, respectively. Total CH(4) production per cow (347±13.6 g/day) decreased with increasing N fertilisation by 4% and grass maturity by 6%. The smaller CH(4) production with advancing grass maturity was offset by a smaller FPCM and lower feed digestibility. As a result, with advancing grass maturity CH(4) emission intensity increased per units of FPCM (15.0±1.00 g CH(4)/kg) by 31% and digestible organic matter intake (33.1±0.78 g CH(4)/kg) by 15%. In addition, emission intensity increased per units of DMI (23.5±0.43 g CH(4)/kg) by 7% and gross energy intake (7.0±0.14% CH(4)) by 9%, implying an increased loss of dietary energy with advancing grass maturity. Rate of N fertilisation had no effect on CH(4) emissions per units of FPCM, DMI and gross energy intake. These results suggest that despite a lower absolute daily CH(4) production with a higher N fertilisation rate, CH(4) emission intensity remains unchanged. A significant reduction of CH(4) emission intensity can be achieved by feeding dairy cows silage of grass harvested at an earlier stage of maturity.
Exposure of ova to cortisol pre-fertilisation affects subsequent behaviour and physiology of brown trout.

PubMed

Sloman, Katherine A

2010-08-01

Even before fertilisation, exposure of ova to high levels of stress corticosteroids can have significant effects on offspring in a variety of animals. In fish, high levels of cortisol in ovarian fluid can elicit morphological changes and reduce offspring survival. Whether there are other more subtle effects, including behavioural effects, of exposure to cortisol pre-fertilisation in fish is unclear. Here I demonstrate that a brief (3h) exposure of brown trout eggs to a physiologically relevant ( approximately 500 microg l(-)(1)) concentration of cortisol pre-fertilisation resulted in changes to developing offspring. Embryos exposed to cortisol pre-fertilisation displayed elevated oxygen consumption and ammonia excretion rates during development. After hatch, in contrast to the effects of cortisol exposure in juvenile fish, fish exposed to cortisol as eggs were more aggressive than control individuals and responded differently within a maze system. Thus, a transient exposure to corticosteroids in unfertilised eggs results in both physiological and behavioural alterations in fish. Copyright 2010 Elsevier Inc. All rights reserved.

Evaluating the use of plant hormones and biostimulators in forage pastures to enhance shoot dry biomass production by perennial ryegrass (Lolium perenne L.).

PubMed

Zaman, Mohammad; Kurepin, Leonid V; Catto, Warwick; Pharis, Richard P

2016-02-01

Fertilisation of established perennial ryegrass forage pastures with nitrogen (N)-based fertilisers is currently the most common practice used on farms to increase pasture forage biomass yield. However, over-fertilisation can lead to undesired environmental impacts, including nitrate leaching into waterways and increased gaseous emissions of ammonia and nitrous oxide to the atmosphere. Additionally, there is growing interest from pastoral farmers to adopt methods for increasing pasture dry matter yield which use 'natural', environmentally safe plant growth stimulators, together with N-based fertilisers. Such plant growth stimulators include plant hormones and plant growth promotive microorganisms such as bacteria and fungi ('biostimulators', which may produce plant growth-inducing hormones), as well as extracts of seaweed (marine algae). This review presents examples and discusses current uses of plant hormones and biostimulators, applied alone or together with N-based fertilisers, to enhance shoot dry matter yield of forage pasture species, with an emphasis on perennial ryegrass. © 2015 Society of Chemical Industry.
Experimental sand burial affects seedling survivorship, morphological traits, and biomass allocation of Ulmus pumila var. sabulosa in the Horqin Sandy Land, China

NASA Astrophysics Data System (ADS)

Tang, Jiao; Busso, Carlos Alberto; Jiang, Deming; Musa, Ala; Wu, Dafu; Wang, Yongcui; Miao, Chunping

2016-07-01

As a native tree species, Ulmus pumila var. sabulosa (sandy elm) is widely distributed in the Horqin Sandy Land, China. However, seedlings of this species have to withstand various depths of sand burial after emergence because of increasing soil degradation, which is mainly caused by overgrazing, climate change, and wind erosion. An experiment was conducted to evaluate the changes in its survivorship, morphological traits, and biomass allocation when seedlings were buried at different burial depths: unburied controls and seedlings buried vertically up to 33, 67, 100, or 133 % of their initial mean seedling height. The results showed that partial sand burial treatments (i.e., less than 67 % burial) did not reduce seedling survivorship, which still reached 100 %. However, seedling mortality increased when sand burial was equal to or greater than 100 %. In comparison with the control treatment, seedling height and stem diameter increased at least by 6 and 14 % with partial burial, respectively. In the meantime, seedling taproot length, total biomass, and relative mass growth rates were at least enhanced by 10, 15.6, and 27.6 %, respectively, with the partial sand burial treatment. Furthermore, sand burial decreased total leaf area and changed biomass allocation in seedlings, partitioning more biomass to aboveground organs (e.g., leaves) and less to belowground parts (roots). Complete sand burial after seedling emergence inhibited its re-emergence and growth, even leading to death. Our findings indicated that seedlings of sandy elm showed some resistance to partial sand burial and were adapted to sandy environments from an evolutionary perspective. The negative effect of excessive sand burial after seedling emergence might help in understanding failures in recruitments of sparse elm in the study region.
Sustainable nitrogen fertilisation in sweet pepper: assessing growth and fruit quality and the potential nitrate pollution from different organic manures.

PubMed

Gómez-López, María D; del Amor, Francisco M

2013-03-30

The use of organic cultivation with manures does not avoid the risk of high nitrate concentrations if nutrient management is inefficient. So we studied the influence of three organic manures combined or not with additional chemical fertilisers on growth and yield of sweet pepper (Capsicum annuum L.), and on the soil and plant N concentrations. After 3 years of organic cultivation, poultry manure caused the highest soil pollution. The evolution of nitrate and organic matter in soil showed a pattern close to that of plant growth. The addition of mineral fertiliser increased vegetative growth and yield, and a cumulative season effect was observed. In treatments with no additional mineral fertiliser N translocation from leaves to fruits happened. A cumulative effect of seasons on fruit quality and a reduction near to 30% was observed in the first fruit quality category after 3 years. The fruit vitamin C content was reduced by increasing N fertilisation. The effects of organic fertiliser on soil and plant growth and yield depended on the type of manure used, its rate, and consecutive crop seasons. Horse manure gave the best combination of agricultural and environmental characteristics and could be used without additional fertigation. © 2012 Society of Chemical Industry.
Amelioration of bauxite residue sand by intermittent additions of nitrogen fertiliser and leaching fractions: The effect on growth of kikuyu grass and fate of applied nutrients.

PubMed

Kaur, Navjot; Phillips, Ian; Fey, Martin V

2016-04-15

Bauxite residue, a waste product of aluminium processing operations is characterised by high pH, salinity and exchangeable sodium which hinders sustainable plant growth. The aim of this study was to investigate the uptake form, optimum application rate and timing of nitrogen fertiliser to improve bauxite residue characteristics for plant growth. Kikuyu grass was grown in plastic columns filled with residue sand/carbonated residue mud mixture (20:1) previously amended with gypsum, phosphoric acid and basal nutrients. The experiment was set up as a 4×4 factorial design comprising four levels of applied nitrogen (N) fertiliser (0, 3, 6 and 12mgNkg(-1) residue) and four frequencies of leaching (16, 8 and 4day intervals). We hypothesised that the use of ammonium sulfate fertiliser would increase retention of N within the rhizosphere thereby encouraging more efficient fertiliser use. We found that N uptake by kikuyu grass was enhanced due to leaching of excess salts and alkalinity from the residue profile. It was also concluded that biomass production and associated N uptake by kikuyu grass grown in residue is dependent on the type of fertiliser used. Copyright © 2016 Elsevier B.V. All rights reserved.
Pathogenicity of Leptographium Species Associated with Loblolly Pine Decline

Treesearch

L. G. Eckhardt; J. P. Jones; Kier D. Klepzig

2004-01-01

Freshly lifted seedlings and 21-year-old trees of loblolly pine were wound-inoculated with Leptographium species recovered from the soil and/or roots of trees with loblolly decline symptoms in central Alabama. Seedlings inoculated with L. procerum in the greenhouse produced significantly fewer root initials and a smaller root mass than control...
Planting oaks in the Central Hardwood Region: a shelterwood approach

Treesearch

Dale R. Weigel

1997-01-01

The success of oak seedlings planted under shelterwoods depends on where they are planted, initial seedling size, nursery undercutting treatments, and whether they are top-clipped before planting. These conclusions are based on planting northern red oak (Quercus rubra L.) and white oak (Q. alba L.) under shelterwoods in Indiana and...
Soil compaction and initial height growth of planted ponderosa pine.

Treesearch

P. H. Cochran; Terry. Brock

1985-01-01

Early height growth of ponderosa pine (Pinus ponderosa Dougl. ex Laws.) seedlings planted in clearcuts in central Oregon was negatively correlated with increasing soil bulk density. Change in bulk density accounted for less than half the total variation in height growth. Although many other factors affect the development of seedlings, compaction...
Incidence of pulmonary and venous thromboembolism in pregnancies after in vitro fertilisation: cross sectional study.

PubMed

Henriksson, Peter; Westerlund, Eli; Wallén, Håkan; Brandt, Lena; Hovatta, Outi; Ekbom, Anders

2013-01-15

To estimate the risk of pulmonary embolism and venous thromboembolism in pregnant women after in vitro fertilisation. Cross sectional study. Sweden. 23,498 women who had given birth after in vitro fertilisation between 1990 and 2008 and 116,960 individually matched women with natural pregnancies. Risk of pulmonary embolism and venous thromboembolism (identified by linkage to the Swedish national patient register) during the whole pregnancy and by trimester. Venous thromboembolism occurred in 4.2/1000 women (n=99) after in vitro fertilisation compared with 2.5/1000 (n=291) in women with natural pregnancies (hazard ratio 1.77, 95% confidence interval 1.41 to 2.23). The risk of venous thromboembolism was increased during the whole pregnancy (P<0.001) and differed between the trimesters (P=0.002). The risk was particularly increased during the first trimester, at 1.5/1000 after in vitro fertilisation versus 0.3/1000 (hazard ratio 4.22, 2.46 to 7.26). The proportion of women experiencing pulmonary embolism during the first trimester was 3.0/10,000 after in vitro fertilisation versus 0.4/10,000 (hazard ratio 6.97, 2.21 to 21.96). In vitro fertilisation is associated with an increased risk of pulmonary embolism and venous thromboembolism during the first trimester. The risk of pulmonary embolism is low in absolute terms but because the condition is a leading cause of maternal mortality and clinical suspicion is critical for diagnosis, an awareness of this risk is important. ClinicalTrials.gov NCT01524393.
An anti-mosquito mixture for domestic use, combining a fertiliser and a chemical or biological larvicide.

PubMed

Darriet, Frédéric

2016-07-01

Plant saucers are an important larval habitat for Aedes aegypti and Ae. albopictus in peridomestic situations. Because NPK fertilisers in plant containers tend to enhance the oviposition of these species, we investigated the effects of Bacillus thuringiensis var. israelensis, spinosad, pyriproxyfen and diflubenzuron larvicides in combination with fertiliser on the adult emergence and fecundity of the mosquitoes coming from plant saucers in controlled greenhouse experiments. NPK + larvicide (NPK-LAV) treatments were tested on Ae. aegypti. Each treatment was compared with water and with fertiliser alone on a total of five houseplants and their saucers. The fertilising treatment was renewed every 30-45 days. With less than 5% imaginal emergence, the NPK + spinosad 0.5% treatment remained effective for 30 days. Both NPK + pyriproxyfen 0.1% and NPK + diflubenzuron 0.25% were effective for 45 days. The average number of eggs laid in the three treatments was similar to the NPK treatment, indicating that spinosad, pyriproxyfen and diflubenzuron did not alter the attraction effect of the fertiliser on egg laying. NPK + pyriproxyfen and NPK + diflubenzuron also had ovicidal activity and an important impact on the fecundity of the Ae. aegypti female imagos and the fertility of their eggs. The addition of NPK fertiliser to insecticides can increase larval control of Aedes mosquitoes. This innovative measure for personal protection, which is harmless for both humans and animals, would be an additional support for the community-based actions led by the institutional services for vector control. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.
Twenty-Two Years of Warming, Fertilisation and Shading of Subarctic Heath Shrubs Promote Secondary Growth and Plasticity but Not Primary Growth

PubMed Central

Campioli, Matteo; Leblans, Niki; Michelsen, Anders

2012-01-01

Most manipulation experiments simulating global change in tundra were short-term or did not measure plant growth directly. Here, we assessed the growth of three shrubs (Cassiope tetragona, Empetrum hermaphroditum and Betula nana) at a subarctic heath in Abisko (Northern Sweden) after 22 years of warming (passive greenhouses), fertilisation (nutrients addition) and shading (hessian fabric), and compare this to observations from the first decade of treatment. We assessed the growth rate of current-year leaves and apical stem (primary growth) and cambial growth (secondary growth), and integrated growth rates with morphological measurements and species coverage. Primary- and total growth of Cassiope and Empetrum were unaffected by manipulations, whereas growth was substantially reduced under fertilisation and shading (but not warming) for Betula. Overall, shrub height and length tended to increase under fertilisation and warming, whereas branching increased mostly in shaded Cassiope. Morphological changes were coupled to increased secondary growth under fertilisation. The species coverage showed a remarkable increase in graminoids in fertilised plots. Shrub response to fertilisation was positive in the short-term but changed over time, likely because of an increased competition with graminoids. More erected postures and large, canopies (requiring enhanced secondary growth for stem reinforcement) likely compensated for the increased light competition in Empetrum and Cassiope but did not avoid growth reduction in the shade intolerant Betula. The impact of warming and shading on shrub growth was more conservative. The lack of growth enhancement under warming suggests the absence of long-term acclimation for processes limiting biomass production. The lack of negative effects of shading on Cassiope was linked to morphological changes increasing the photosynthetic surface. Overall, tundra shrubs showed developmental plasticity over the longer term. However, such plasticity was associated clearly with growth rate trends only in fertilised plots. PMID:22511968
Substitution of peat, fertiliser and manure by compost in hobby gardening: user surveys and case studies.

PubMed

Andersen, Jacob K; Christensen, Thomas H; Scheutz, Charlotte

2010-12-01

Four user surveys were performed at recycle centres (RCs) in the Municipalities of Aarhus and Copenhagen, Denmark, to get general information on compost use and to examine the substitution of peat, fertiliser and manure by compost in hobby gardening. The average driving distance between the users' households and the RCs was found to be 4.3 km and the average amount of compost picked up was estimated at 800 kg per compost user per year. The application layer of the compost varied (between 1 and 50 cm) depending on the type of use. The estimated substitution (given as a fraction of the compost users that substitute peat, fertiliser and manure with compost) was 22% for peat, 12% for fertiliser and 7% for manure (41% in total) from the survey in Aarhus (n=74). The estimate from the survey in Copenhagen (n=1832) was 19% for peat, 24% for fertiliser and 15% for manure (58% in total). This is the first time, to the authors' knowledge, that the substitution of peat, fertiliser and manure with compost has been assessed for application in hobby gardening. Six case studies were performed as home visits in addition to the Aarhus surveys. From the user surveys and the case studies it was obvious that the total substitution of peat, fertiliser and manure was not 100%, as is often assumed when assigning environmental credits to compost. It was more likely around 50% and thus there is great potential for improvement. It was indicated that compost was used for a lot of purposes in hobby gardening. Apart from substitution of peat, fertiliser and manure, compost was used to improve soil quality and as a filling material (as a substitute for soil). Benefits from these types of application are, however, difficult to assess and thereby quantify. Copyright © 2010 Elsevier Ltd. All rights reserved.
Increased vapor pressure deficit due to higher temperature leads to greater transpiration and faster mortality during drought for tree seedlings common to the forest-grassland ecotone.

PubMed

Will, Rodney E; Wilson, Stuart M; Zou, Chris B; Hennessey, Thomas C

2013-10-01

Tree species growing along the forest-grassland ecotone are near the moisture limit of their range. Small increases in temperature can increase vapor pressure deficit (VPD) which may increase tree water use and potentially hasten mortality during severe drought. We tested a 40% increase in VPD due to an increase in growing temperature from 30 to 33°C (constant dewpoint 21°C) on seedlings of 10 tree species common to the forest-grassland ecotone in the southern Great Plains, USA. Measurement at 33 vs 30°C during reciprocal leaf gas exchange measurements, that is, measurement of all seedlings at both growing temperatures, increased transpiration for seedlings grown at 30°C by 40% and 20% for seedlings grown at 33°C. Higher initial transpiration of seedlings in the 33°C growing temperature treatment resulted in more negative xylem water potentials and fewer days until transpiration decreased after watering was withheld. The seedlings grown at 33°C died 13% (average 2 d) sooner than seedlings grown at 30°C during terminal drought. If temperature and severity of droughts increase in the future, the forest-grassland ecotone could shift because low seedling survival rate may not sufficiently support forest regeneration and migration. © 2013 The Authors. New Phytologist © 2013 New Phytologist Trust.
Cost Effectiveness of Natural Regeneration for Sustaining Production Continuity in Commercial Pine Plantations

Treesearch

T.R. Clason

2002-01-01

Reforestation is a key to production continuity in commercial pine plantations. Although natural and artificial regeneration methods have been used successfully for pine seedling establishment, it is seedling growth during early stage of plantation development that affects the financial potential of a pine plantation. A study was initiated to determine the effect of...
Initial response of underplanted yellow poplar and cherrybark oak seedlings to four levels of mechanical midstory removal

Treesearch

John M. Lhotka; Edward F. Loewenstein

2006-01-01

Midstory removal has been suggested as a possible enhancement strategy to develop seedling pools in stands lacking vigorous advanced oak (Quercus spp.) reproduction. However, for successful implementation, silviculturists must understand the differential growth responses of oak and its competitors to conditions created by midstory removal. To further...
Nursery practices, seedling sizes, and field performance.

Treesearch

William I. Stein

1988-01-01

Highlights are presented from a large cooperative study to determine the combined effects of nursery cultural practices on the initial size and subsequent field performance of 2+0 Douglas-fir seedlings. The study involved seven sources of stock produced in three different nurseries and field plantings made over 3 years on 28 sites in southwestern Oregon. Seedbed...
Control of brush regrowth with herbicides on pine plantations in northern California

Treesearch

Jay R. Bentley; Kenneth M. Estes

1978-01-01

On large plots cleared in 1961 at three California mountain locations, different herbicide treatments were applied once, twice, or three times in consecutive years, beginning in 1962. Results were evaluated in 1965. A single spray was unsatisfactory; only the initial seedlings and weaker sprouting plants were killed, and many new seedlings became established in 1963...
Relationship between tillage intensity and initial growth of loblolly pine seedlings

Treesearch

M. Chad Lincoln; Rodney E. Will; Emily A. Carter; John R. Britt; Lawrence A. Morris

2006-01-01

To determine the relationship between changes in soil attributes associated with differing tillage intensities and growth of loblolly pine seedlings, we measured soil moisture, nitrogen (N) availability, and soil strength across a range of tillage treatments on an Orangeburg soil series near Cuthbert, GA (four replications). We then correlated these measurements to the...
Functional Profiling Identifies Genes Involved in Organ-Specific Branches of the PIF3 Regulatory Network in Arabidopsis[C][W

PubMed Central

Sentandreu, Maria; Martín, Guiomar; González-Schain, Nahuel; Leivar, Pablo; Soy, Judit; Tepperman, James M.; Quail, Peter H.; Monte, Elena

2011-01-01

The phytochrome (phy)-interacting basic helix-loop-helix transcription factors (PIFs) constitutively sustain the etiolated state of dark-germinated seedlings by actively repressing deetiolation in darkness. This action is rapidly reversed upon light exposure by phy-induced proteolytic degradation of the PIFs. Here, we combined a microarray-based approach with a functional profiling strategy and identified four PIF3-regulated genes misexpressed in the dark (MIDAs) that are novel regulators of seedling deetiolation. We provide evidence that each one of these four MIDA genes regulates a specific facet of etiolation (hook maintenance, cotyledon appression, or hypocotyl elongation), indicating that there is branching in the signaling that PIF3 relays. Furthermore, combining inferred MIDA gene function from mutant analyses with their expression profiles in response to light-induced degradation of PIF3 provides evidence consistent with a model where the action of the PIF3/MIDA regulatory network enables an initial fast response to the light and subsequently prevents an overresponse to the initial light trigger, thus optimizing the seedling deetiolation process. Collectively, the data suggest that at least part of the phy/PIF system acts through these four MIDAs to initiate and optimize seedling deetiolation, and that this mechanism might allow the implementation of spatial (i.e., organ-specific) and temporal responses during the photomorphogenic program. PMID:22108407
Early embryo mortality in natural human reproduction: What the data say

PubMed Central

Jarvis, Gavin E.

2017-01-01

How many human embryos die between fertilisation and birth under natural conditions? It is widely accepted that natural human embryo mortality is high, particularly during the first weeks after fertilisation, with total prenatal losses of 70% and higher frequently claimed. However, the first external sign of pregnancy occurs two weeks after fertilisation with a missed menstrual period, and establishing the fate of embryos before this is challenging. Calculations are additionally hampered by a lack of data on the efficiency of fertilisation under natural conditions. Four distinct sources are used to justify quantitative claims regarding embryo loss: (i) a hypothesis published by Roberts & Lowe in The Lancet is widely cited but has no practical quantitative value; (ii) life table analyses give consistent assessments of clinical pregnancy loss, but cannot illuminate losses at earlier stages of development; (iii) studies that measure human chorionic gonadotrophin (hCG) reveal losses in the second week of development and beyond, but not before; and (iv) the classic studies of Hertig and Rock offer the only direct insight into the fate of human embryos from fertilisation under natural conditions. Re-examination of Hertig’s data demonstrates that his estimates for fertilisation rate and early embryo loss are highly imprecise and casts doubt on the validity of his numerical analysis. A recent re-analysis of hCG study data concluded that approximately 40-60% of embryos may be lost between fertilisation and birth, although this will vary substantially between individual women. In conclusion, natural human embryo mortality is lower than often claimed and widely accepted. Estimates for total prenatal mortality of 70% or higher are exaggerated and not supported by the available data. PMID:28580126
Incidence of pulmonary and venous thromboembolism in pregnancies after in vitro fertilisation: cross sectional study

PubMed Central

Westerlund, Eli; Wallén, Håkan; Brandt, Lena; Hovatta, Outi; Ekbom, Anders

2013-01-01

Objective To estimate the risk of pulmonary embolism and venous thromboembolism in pregnant women after in vitro fertilisation. Design Cross sectional study. Setting Sweden. Participants 23 498 women who had given birth after in vitro fertilisation between 1990 and 2008 and 116 960 individually matched women with natural pregnancies. Main outcome measures Risk of pulmonary embolism and venous thromboembolism (identified by linkage to the Swedish national patient register) during the whole pregnancy and by trimester. Results Venous thromboembolism occurred in 4.2/1000 women (n=99) after in vitro fertilisation compared with 2.5/1000 (n=291) in women with natural pregnancies (hazard ratio 1.77, 95% confidence interval 1.41 to 2.23). The risk of venous thromboembolism was increased during the whole pregnancy (P<0.001) and differed between the trimesters (P=0.002). The risk was particularly increased during the first trimester, at 1.5/1000 after in vitro fertilisation versus 0.3/1000 (hazard ratio 4.22, 2.46 to 7.26). The proportion of women experiencing pulmonary embolism during the first trimester was 3.0/10 000 after in vitro fertilisation versus 0.4/10 000 (hazard ratio 6.97, 2.21 to 21.96). Conclusions In vitro fertilisation is associated with an increased risk of pulmonary embolism and venous thromboembolism during the first trimester. The risk of pulmonary embolism is low in absolute terms but because the condition is a leading cause of maternal mortality and clinical suspicion is critical for diagnosis, an awareness of this risk is important. Trial registration ClinicalTrials.gov NCT01524393. PMID:23321489

The role of the megagametophyte in maintaining loblolly pine (Pinus taeda L.) seedling arginase gene expression in vitro.

PubMed

Todd, Christopher D; Gifford, David J

2002-05-01

Following loblolly pine (Pinus taeda L.) seed germination, storage-protein breakdown in the megagametophyte and in the seedling results in a large increase in the seedling's free amino acid pool. A substantial portion of both the storage proteins and the amino acid pool is arginine, a very efficient nitrogen-storage compound. Free arginine is hydrolyzed in the seedling by the enzyme arginase (EC 3.5.3.1), which is under strong developmental control. At present, regulation of arginase in conifers is not well understood. Here we report the utilization of an in vitro culture system to address the separate impacts of the seedling and megagametophyte tissues on arginase enzyme activity, protein levels and patterns of gene expression. We also describe the generation of an anti-arginase antibody prepared from a histidine-tagged loblolly pine arginase fusion protein expressed in Escherichia coli. Our results indicate that arginase gene expression in the seedling is initiated by the seedling itself and then maintained or up-regulated by the megagametophyte. The contribution of storage-protein breakdown and the free amino acid pool, particularly arginine, in this regulation is also addressed.
Establishing native grasses in a big sagebrush-dominated site: an intermediate restoration step

USGS Publications Warehouse

Huber-Sannwald, Elisabeth; Pyke, David A.

2005-01-01

Many semiarid rangelands in the Great Basin, U.S.A., are shifting dominance to woody species as a consequence of land degradation including intense livestock grazing and fire suppression. Whereas past rehabilitation efforts in Big sagebrush (Artemisia tridentata) steppes removed the shrub and added introduced forage grasses to successfully shift communities from shrublands to grasslands, current consensus is that native species should be included in restoration projects and that retention of some woody plants is desirable. We examined the potential for interseeding grasses into dense shrub communities as a precursor to thinning shrubs and releasing grasses from shrub interference. We compared seedling establishment of the native grass, Bluebunch wheatgrass (Pseudoroegneria spicata), with that of the Eurasia grass, Crested wheatgrass (Agropyron desertorum), in dense Ar. tridentata stands. Shrubs may play an important role as nurse plants for seedling establishment (reduced solar radiation, 'island of fertility' effect) but result in highly contrasting light environments and root interference for seedlings. In experimental plots, we examined effects of Ar. tridentata shade levels (0, 40, 70, and 90% reduction of solar radiation) and initial root exclusion (present/absent) on the establishment and growth of P. spicata and Ag. desertorum seedlings. With this design we evaluated the interference effects of Ar. tridentata on the two grasses and identified the most beneficial microsites for grass restoration in Ar. tridentataa??dominated communities. We predicted seedling survival and growth to be greater under moderate shade (40% reduction) and limited root competition than under no or strong shade conditions (0 and 90%) and unrestricted root interactions. Fifty to 85% of the P. spicata and Ag. desertorum seedlings survived the dry summer months of 1995 and 1996 and the intervening winter. Neither shading nor root exclusion from Ar. tridentata affected final seedling survival of either species. Seedling biomass of both grass species was negatively affected by initial root interactions with Ar. tridentata. However, the analysis of seedling biomass variability (coefficient of variation) indicated that in all shade and root-exclusion treatments, some seedlings of both species developed to large individuals to survive in Ar. tridentataa??dominated rangelands. Thus, the use of interseeding techniques shows promise for restoring herbaceous species in dense Ar. tridentata stands and should be given further consideration when shrub retention is an important consideration.
Refugial forests of the southern Appalachians: photosynthesis and survival in current-year Abies fraseri seedlings.

PubMed

Johnson, Daniel M; Smith, William K

2005-11-01

Fraser fir (Abies fraseri (Pursh) Poiret) is an endemic, high-elevation conifer confined to six relict mountaintop communities in the southern Appalachian Mountains, USA. High adult mortality has occurred over the past 50 years, possibly the result of an introduced insect (Adelges piceae Ratzeburg), air pollution, or both. Knowledge of the mechanisms of and limitations to seedling establishment may allow reestablisment and perpetuation of this unique community type, notwithstanding global climate change. We monitored seedling emergence and mortality in relation to photosynthetic performance and water relations in microsites differing in canopy openness (sunlight exposure) over the summer of 2004. Abundance of cotyledonous seedlings in early summer was 2.3 times greater (849 versus 366 seedlings m(-2)) in microsites with lower sky exposure (greater canopy closure) than in microsites with greater sky exposure (greater canopy openness). In contrast, late-season abundance and survival were greater in areas beneath more open canopies than in areas beneath less open canopies (3.3 times and 11.7 times greater, respectively). However, newly emerged seedling survival in a completely open site (no overhead canopy) was zero, despite an initial density of 124 seedlings m(-2). Seedling water status was similar in open- and closed-canopy sites (-0.52 and -0.74 MPa, respectively). Photosynthetic carbon gain was higher in newly emerged seedlings at open canopy than at closed canopy sites, especially during early morning. Based on photosynthetic light response curves and measured sunlight regimes, seedlings in open canopy sites were estimated to assimilate 3.3-4.5 times more carbon than seedlings at closed sites. Reductions in carbon gain of closed-site seedlings, primarily a result of limited sunlight, corresponded to substantial increases in seedling mortality (98 versus 79% in open canopy sites). Thus, sunlight exposure, which reflects overstory canopy structure, appears to be an important factor influencing newly emerged seedling survival and distribution.
Organo-mineral fertilisers from glass-matrix and organic biomasses: a new way to release nutrients. A novel approach to fertilisation based on plant demand.

PubMed

Trinchera, Alessandra; Allegra, Maria; Rea, Elvira; Roccuzzo, Giancarlo; Rinaldi, Simona; Sequi, Paolo; Intrigliolo, Francesco

2011-10-01

A glass-matrix fertiliser (GMF), a by-product from ceramic industries, releases nutrients only in the presence of complexing solutions, similar to those exuded by plant roots. This ensures a slow release of nutrients over time, limiting the risk of their loss in the environment. With the aim to improve fertiliser performance, GMF was mixed with vine vinasse (DVV), pastazzo (a by-product of the citrus processing industry, PAS) or green compost (COMP) and nutrient release was evaluated by citric and chloridric acid extraction, at different concentrations. Theoretical and actual nutrients release were compared to evaluate possible synergistic effects due to the organic component added to the mineral fertiliser: phosphorus (+7.1%), K (+4.8%), Fe (+8.5%) and Zn (+5.5%) were released more efficiently by 2% citric acid from GMF + DVV, while Ca availability was increased (+5.3%) by 2% citric acid from GMF + PAS mixture. Both DVV and COMP increased by 12-18% the Fe release from GFM matrix. Organic biomasses added to GMF increased the release of some macro and micronutrients through an 'activation effect', which suggests the employment of these organo-mineral fertilisers also in short-cycle crops production. Moreover, the re-use of some agro-industrial organic residues gives another 'adding value' to this novel organo-mineral fertilfertilisers. Copyright © 2011 Society of Chemical Industry.
Distribution of arsenic and risk assessment of activities on a golf course fertilised with arsenic-containing Ascophyllum nodosum seaweed.

PubMed

O'Neill, Antonia; Gupta, Bhaskar Sen; Phillips, Debra H

2014-06-01

The use of seaweed fertilisers in sports green maintenance has become a common practice across the globe due to its image as an "eco-friendly" alternative to chemical fertilisers. The aim of this study was to characterise the risk of human exposure to arsenic (As), via dermal absorption, from golfing activities on a private golf course in the UK, where As contaminated seaweed fertiliser (~100mg/kg d.wt.) is applied. This was fulfilled by, 1) determining As concentrations in shallow soils with GIS geo-statistical analysis, 2) measuring As concentrations from an on-site borehole groundwater well, and (3) developing a risk assessment calculation for golfing activities based on field and questionnaire data. Total As concentrations in shallow soils were less than the UK threshold for domestic soils, however, frequent and sustained dermal contact between site-users and surface soil attributed to a maximum carcinogenic risk value of 2.75×10(-4), which is in the upper limit of the acceptable risk range. Arsenic concentrations in underlying groundwater exceeded the WHO's permissible drinking water standard, demonstrating the risk of groundwater contamination following the application of seaweed fertiliser to golf course soils. This is the first risk study on dermal As absorption via the application of a seaweed fertiliser. Copyright © 2014 Elsevier B.V. All rights reserved.
Oocyte glutathione and fertilisation outcome of Macaca nemestrina and Macaca fascicularis in in vivo- and in vitro-matured oocytes

PubMed Central

Curnow, E. C.; Ryan, J. P.; Saunders, D. M.; Hayes, E. S.

2010-01-01

Fertilisation and development of IVM non-human primate oocytes is limited compared with that of in vivo-matured (IVO) oocytes. The present study describes the IVM of macaque oocytes with reference to oocyte glutathione (GSH). Timing of maturation, comparison of IVM media and cysteamine (CYS) supplementation as a modulator of GSH were investigated. A significantly greater proportion of oocytes reached MII after 30 h compared with 24 h of IVM. Following insemination, IVM oocytes had a significantly lower incidence of normal fertilisation (i.e. 2PN = two pronuclei and at least one polar body) and a higher rate of abnormal fertilisation (1PN = one pronucleus and at least one polar body) compared with IVO oocytes. Immunofluorescence of 1PN zygotes identified incomplete sperm head decondensation and failure of male pronucleus formation as the principal cause of abnormal fertilisation in IVM oocytes. The IVO oocytes had significantly higher GSH content than IVM oocytes. Cumulus-denuded oocytes had significantly lower GSH following IVM compared with immature oocytes at collection. Cysteamine supplementation of the IVM medium significantly increased the GSH level of cumulus-intact oocytes and reduced the incidence of 1PN formation, but did not improve GSH levels of the denuded oocyte. Suboptimal GSH levels in macaque IVM oocytes may be related to reduced fertilisation outcomes. PMID:20591337
Live Birth from Slow-Frozen Rabbit Oocytes after In Vivo Fertilisation

PubMed Central

Jiménez-Trigos, Estrella; Vicente, José S.; Marco-Jiménez, Francisco

2013-01-01

In vivo fertilisation techniques such as intraoviductal oocyte transfer have been considered as alternatives to bypass the inadequacy of conventional in vitro fertilisation in rabbit. There is only one study in the literature, published in 1989, that reports live offspring from cryopreserved rabbit oocytes. The aim of the present study was to establish the in vivo fertilisation procedure to generate live offspring with frozen oocytes. First, the effect of two recipient models (i) ovariectomised or (ii) oviduct ligated immediately after transfer on the ability of fresh oocytes to fertilise were compared. Second, generation of live offspring from slow-frozen oocytes was carried out using the ligated oviduct recipient model. Throughout the experiment, recipients were artificially inseminated 9 hours prior to oocyte transfer. In the first experiment, two days after unilateral transfer of fresh oocytes, oviducts and uterine horns were flushed to assess embryo recovery rates. The embryo recovery rates were low compared to control in both ovariectomised and ligated oviduct groups. However, ligated oviduct recipient showed significantly (P<0.05) higher embryo recovery rates compared to ovariectomised and control-transferred. In the second experiment, using bilateral oviduct ligation model, all females that received slow-frozen oocytes became pregnant and delivered a total of 4 live young naturally. Thus, in vivo fertilisation is an effective technique to generate live offspring using slow-frozen oocytes in rabbits. PMID:24358281
Oocyte glutathione and fertilisation outcome of Macaca nemestrina and Macaca fascicularis in in vivo- and in vitro-matured oocytes.

PubMed

Curnow, E C; Ryan, J P; Saunders, D M; Hayes, E S

2010-01-01

Fertilisation and development of IVM non-human primate oocytes is limited compared with that of in vivo-matured (IVO) oocytes. The present study describes the IVM of macaque oocytes with reference to oocyte glutathione (GSH). Timing of maturation, comparison of IVM media and cysteamine (CYS) supplementation as a modulator of GSH were investigated. A significantly greater proportion of oocytes reached MII after 30 h compared with 24 h of IVM. Following insemination, IVM oocytes had a significantly lower incidence of normal fertilisation (i.e. 2PN = two pronuclei and at least one polar body) and a higher rate of abnormal fertilisation (1PN = one pronucleus and at least one polar body) compared with IVO oocytes. Immunofluorescence of 1PN zygotes identified incomplete sperm head decondensation and failure of male pronucleus formation as the principal cause of abnormal fertilisation in IVM oocytes. The IVO oocytes had significantly higher GSH content than IVM oocytes. Cumulus-denuded oocytes had significantly lower GSH following IVM compared with immature oocytes at collection. Cysteamine supplementation of the IVM medium significantly increased the GSH level of cumulus-intact oocytes and reduced the incidence of 1PN formation, but did not improve GSH levels of the denuded oocyte. Suboptimal GSH levels in macaque IVM oocytes may be related to reduced fertilisation outcomes.
Pre-harvest nitrogen and azoxystrobin application enhances raw product quality and post-harvest shelf-life of baby spinach (Spinacia oleracea L.).

PubMed

Conversa, Giulia; Bonasia, Anna; Lazzizera, Corrado; Elia, Antonio

2014-12-01

Baby spinach was cultivated under spring or winter conditions to investigate the effect of azoxystrobin and, only in the winter cycle, of nitrogen fertilisation (0, 80 and 120 kg ha(-1) of N) on yield and product morphological traits at harvest and on the physical, visual, bio-physiological, nutritional and anti-nutritional characteristics change during cold storage. The yield was 37% higher in spring than in the overwinter cycle. Spring grown plant had leaves of lighter colour, lower in dry matter content, higher in ascorbic acid, nitrate, and total phenol content. They had higher weight loss during storage than the winter product. Fresh weight was favoured by azoxystrobin only in the non-fertilised plants. During storage azoxystrobin reduced leaf dehydration, contrasted weight loss and the increase in phenols in leaves from fertilised plants. N supply positively affected yield, and greenness of raw and stored leaves. N fertilisation lowered weight loss due to respiration and showed a protective effect on membrane integrity during storage. Azoxystrobin proved effective in reducing nitrate leaf content. Azoxystrobin, especially in fertilised crop, is useful in improving the physiological quality, the safety, and the nutritional quality of baby spinach. A rate of 80 kg ha(-1) can be suggested as optimum N fertilisation. © 2014 Society of Chemical Industry.
Characterization biometric and morphophysiological of Peach rootstock seeds using images of their seedling vigor.

PubMed

Souza, Aline Das Graças; Smiderle, Oscar Jose; Bianchi, Valmor Joao

2018-04-26

This study aimed to evaluate the efficiency of using the computerized imaging seed analysis system (SAS) in the biometric and morphophysiological characterization of seeds and the initial growth of seedlings from peach rootstocks. The experimental design was completely randomized with five replicates of 20 seeds. The variables analyzed were degree of seed humidity, length and width of seeds measured by SAS technology and manual measurements, mean germination time, germination percentage, radicle length and width, taproot length, length of the aerial part and taproot/aerial part ratio. The highest seed length, germination percentage (100%) and lower germination time (11.3), were obtained with the cv. Capdeboscq while, 'Tsukuba 1', 2' and 3' had intermediate seedlings length, varying from 1.55 to 1.65 cm with mean germination times between 14.5 and 18.0 days and average germination percentage of 96%. The computerized analysis of images is fast and efficient for biometric evaluations such as seed width and length, as well as initial growth of peach tree seedlings. The cvs Capdeboscq, Flordaguard and Tsukuba 2 presented greater radicle width, length and a mean taproot/aerial part ratio equal to 2, as well as higher number of adventitious roots, which indicated a strong positive correlation between radicle length, taproot length and initial seedling growth. The continuity of the research will certainly allow the development of reliable procedures for other species, besides allowing the identification of wider alternatives for the use of this system for the expansion of knowledge in the areas of physiology and evaluation of the physiological potential of seeds. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.
In vitro fertilisation treatment and factors affecting success.

PubMed

Huang, Jack Yu Jen; Rosenwaks, Zev

2012-12-01

The efficacy of assisted reproductive technologies has improved significantly over the past decades. The main indications for in vitro fertilisation include tubal obstruction, severe male-factor infertility, severe endometriosis, ovulatory dysfunction, diminished ovarian reserve, and infertility of unexplained cause. In vitro fertilisation has also become an effective treatment option for couples wishing to undergo pre-implantation genetic diagnosis or screening, and for those wishing to cryopreserve their oocytes or embryos for preservation of fertility. The management of women in late reproductive age poses a major challenge; the optimum in vitro fertilisation treatment for poor responders remains elusive. The success of in vitro fertilisation treatment can be optimised by taking an individualised, patient-centered approach to controlled ovarian hyperstimulation. Key components involve selection of an appropriate controlled ovarian protocol, close-cycle monitoring, adjustment of gonadotropin dosage to avoid hyper-response, and individualised timing of human chorionic gonadotropin injection. Future directions of assisted reproductive technologies include development of non-invasive embryo selection methods, use of transcriptomics, proteomics, metabolomics, and time-lapse imaging technologies. Copyright © 2012 Elsevier Ltd. All rights reserved.
Microgravity effects on different stages of higher plant life cycle and completion of the seed-to-seed cycle.

PubMed

De Micco, V; De Pascale, S; Paradiso, R; Aronne, G

2014-01-01

Human inhabitation of Space requires the efficient realisation of crop cultivation in bioregenerative life-support systems (BLSS). It is well known that plants can grow under Space conditions; however, perturbations of many biological phenomena have been highlighted due to the effect of altered gravity and its possible interactions with other factors. The mechanisms priming plant responses to Space factors, as well as the consequences of such alterations on crop productivity, have not been completely elucidated. These perturbations can occur at different stages of plant life and are potentially responsible for failure of the completion of the seed-to-seed cycle. After brief consideration of the main constraints found in the most recent experiments aiming to produce seeds in Space, we focus on two developmental phases in which the plant life cycle can be interrupted more easily than in others also on Earth. The first regards seedling development and establishment; we discuss reasons for slow development at the seedling stage that often occurs under microgravity conditions and can reduce successful establishment. The second stage comprises gametogenesis and pollination; we focus on male gamete formation, also identifying potential constraints to subsequent fertilisation. We finally highlight how similar alterations at cytological level can not only be common to different processes occurring at different life stages, but can be primed by different stress factors; such alterations can be interpreted within the model of 'stress-induced morphogenic response' (SIMR). We conclude by suggesting that a systematic analysis of all growth and reproductive phases during the plant life cycle is needed to optimise resource use in plant-based BLSS. © 2013 German Botanical Society and The Royal Botanical Society of the Netherlands.
Dying piece by piece: carbohydrate dynamics in aspen seedlings under severe carbon stress and starvation

NASA Astrophysics Data System (ADS)

Wiley, Erin; Chow, Pak; Landhäusser, Simon

2016-04-01

Carbon stress and starvation remain poorly understood in trees, despite their potential role in mortality from a variety of agents. To explore the effects of carbon stress on nonstructural carbohydrate (NSC) dynamics and recovery potential and to examine the process of starvation, we grew aspen seedlings under one of three levels of shade: 40% (light shade), 8% (medium shade), and 4% (dark shade) of full sunlight. We then exposed seedlings to 24 hours darkness at either 20° or 28° C until trees had died. Periodically, seedlings were harvested for NSC analysis and to measure stem and root respiration. In addition, some seedlings were moved back into the light to determine if recovery was possible at certain points during starvation. Specifically, we sought to address the following questions: 1) Do NSC concentrations or mass influence tree survival under carbon stress? 2) At what carbohydrate levels do trees fail to recover and starve? 3) Does temperature affect the NSC level at which trees starve? Increasing shade reduced growth, but surprisingly did not reduce NSC levels, except in a portion of deep shade seedlings that experienced dieback. Once in darkness, leaves died first, with final NSC levels ranging from ~4% (Medium shade, 28 degrees) to 7.5% (Light shade). Stem death generally occurred gradually down the stem. Stem tissues retained ~1-2% NSC when dead. Recovery was still possible when only the upper half of the stem had died; at this point, seedlings had relatively high root NSC levels in their remaining roots (7-10%), with 1-3% starch. No trees recovered after the whole stem had died, at which point, some trees root systems were completely dead. However, most retained substantial amounts of live roots, averaging 5-6% NSC, with 0.25-1.5% starch. Despite the initially similar NSC concentrations, light shade seedlings took longer to reach half stem and whole stem death than seedlings from medium and dark shade. Longer survival times were associated with greater initial NSC pool sizes and lower mass-specific respiration rates. Higher temperatures reduced the time until tissue death and also tended to reduce NSC levels at death in some tissues. Survival time during starvation appeared to be controlled not only by the size of initial reserves, but by the rate of respiration. Relatively high leaf NSC levels of dead leaves observed during drought and during fall leaf abscission are within the range of leaf NSC levels of starved leaves seen here. Patterns of nonzero tissue NSC and the piecewise progression of mortality often observed in mature trees are not inconsistent with the process of carbon starvation, which may contribute to tree death by many causes.
Pregermination heat shock and seedling growth of fire-following Fabaceae from four Mediterranean-climate regions

NASA Astrophysics Data System (ADS)

Hanley, Mick E.; Fenner, Michael; Ne'eman, Gidi

2001-12-01

The role of heat-shock in stimulating the germination of soil-stored seeds from fire-following plant species is well known. However, the effects of high pre-germination temperatures on subsequent seedling growth are less well understood. In this study, we examined the effect of pre-germination heat shock at five temperatures (60°, 75°, 90°, 105° and 120°C, each applied for 5 min) on the seedling growth of four, fire-following Fabaceae species from four Mediterranean-type ecosystems; Hippocrepis multisiliquosa (Israel), Gastrolobium villosum (Western Australia), Cyclopia pubescens (South Africa) and Lupinus succulentus (California). Following heat treatment and subsequent germination, seedlings were grown in controlled conditions before being harvested at either 10, 20- or 40 d old. A significant increase in mean dry weight biomass was found at 10 days for Hippocrepis seedlings germinated from seeds pre-heated to 90°C. However, subsequent comparison of mean dry weight biomass for seedlings of this species at 20 and 40 d old showed no significant response to heat shock pre-treatment. Similarly, an initial increase in growth of Gastrolobium seedlings germinated from seeds heated to 90° and 105°C disappeared as the plants matured. Seedling growth of Lupinus and Cyclopia was unaffected by the pre-germination heat treatment of their seeds. Since seedling competition is influenced by the size and growth rates of neighbouring plants, any changes in seedling growth rates as a consequence of the temperature environment experienced by their seeds, may therefore influence patterns of post-fire plant community recovery.
Flowering, die-back and recovery of a semelparous woody bamboo in the Atlantic Forest

NASA Astrophysics Data System (ADS)

Montti, Lía; Campanello, Paula I.; Goldstein, Guillermo

2011-07-01

Chusquea ramosissima is a semelparous woody bamboo growing in the understory of the semideciduous Atlantic Forest that increases in abundance after disturbance and consequently has profound effects on vegetation dynamics. Flowering and death of C. ramosissima may open a window of opportunity leaving space vacant for the recruitment of tree seedlings. We describe the flowering pattern and seedling demography of this species at different spatio-temporal scales between the years 2001 and 2009, and evaluate if tree seedling abundance of canopy species increased after the flowering event. At a landscape scale, flowering sites were interspersed with sites that did not flower. At a local scale, the flowering extended over 5 years, with flowering and non-flowering culms intermingled, also in small patches (i.e., 4 m 2). Seeds germinated soon after flowering and die-back. Four successive seedling cohorts were studied. Mortality rate was high during the first 4 months after seedling emergence but several fast-growing seedlings were able to become established successfully. At the end of the study, 10%-20% of the initial number of bamboo seedlings in each cohort survived. Seedling abundance of tree canopy species was similar in flowering and non-flowering sites. C. ramosissima was able to re-colonize and perpetuate in sites it previously occupied. The coexistence of flowering and non-flowering culms at different spatio-temporal scales and clonal growth by rhizomes, together with the successful bamboo seedlings establishment, enhanced bamboo persistence in gaps and disturbed sites. Flowering and death of C. ramosissima did not facilitate seedling growth of canopy tree species.
Greenhouse gas emissions and stocks of soil carbon and nitrogen from a 20-year fertilised wheat-maize intercropping system: A model approach.

PubMed

Zhang, Xubo; Xu, Minggang; Liu, Jian; Sun, Nan; Wang, Boren; Wu, Lianhai

2016-02-01

Accurate modelling of agricultural management impacts on greenhouse gas emissions and the cycling of carbon and nitrogen is complicated due to interactions between various processes and the disturbance caused by field management. In this study, a process-based model, the Soil-Plant-Atmosphere Continuum System (SPACSYS), was used to simulate the effects of different fertilisation regimes on crop yields, the dynamics of soil organic carbon (SOC) and total nitrogen (SN) stocks from 1990 to 2010, and soil CO2 (2007-2010) and N2O (2007-2008) emissions based on a long-term fertilisation experiment with a winter-wheat (Triticum Aestivum L.) and summer-maize (Zea mays L.) intercropping system in Eutric Cambisol (FAO) soil in southern China. Three fertilisation treatments were 1) unfertilised (Control), 2) chemical nitrogen, phosphorus and potassium (NPK), and 3) NPK plus pig manure (NPKM). Statistical analyses indicated that the SPACSYS model can reasonably simulate the yields of wheat and maize, the evolution of SOC and SN stocks and soil CO2 and N2O emissions. The simulations showed that the NPKM treatment had the highest values of crop yields, SOC and SN stocks, and soil CO2 and N2O emissions were the lowest from the Control treatment. Furthermore, the simulated results showed that manure amendment along with chemical fertiliser applications led to both C (1017 ± 470 kg C ha(-1) yr(-1)) and N gains (91.7 ± 15.1 kg N ha(-1) yr(-1)) in the plant-soil system, while the Control treatment caused a slight loss in C and N. In conclusion, the SPACSYS model can accurately simulate the processes of C and N as affected by various fertilisation treatments in the red soil. Furthermore, application of chemical fertilisers plus manure could be a suitable management for ensuring crop yield and sustaining soil fertility in the red soil region, but the ratio of chemical fertilisers to manure should be optimized to reduce C and N losses to the environment. Copyright © 2015 Elsevier Ltd. All rights reserved.
Limited evolutionary divergence of seedlings after the domestication of plant species.

PubMed

Milla, R; Morente-López, J

2015-01-01

The most vulnerable stage in the life of plants is the seedling. The transition from wild to agricultural land that plants experienced during and after domestication implied a noticeable change in the seedlings' environment. Building on current knowledge of seedling ecology, and on previous studies of cassava, we hypothesise that cultivation should have promoted epigeal germination of seedlings, and more exposed and photosynthetic cotyledons. To test this hypothesis, we phenotyped seedling morpho-functional traits in a set of domesticated and wild progenitor accessions of 20 Eudicot herbaceous crop species. Qualitative traits like epi- versus hypogeal germination, leafy versus storage type of cotyledons, or crypto- versus phanerocotyledonar germination, remained conserved during the domestication of all 20 species. Lengths of hypocotyls and epicotyls, of cotyledon petioles, and indices of cotyledon exposure to the aboveground environment changed during evolution under cultivation. However, those changes occurred in diverse directions, depending on the crop species. No common seedling phenotypic convergence in response to domestication was thus detected among the group of species studied here. Also, none of the 20 crops evolved in accordance with our initial hypothesis. Our results reject the idea that strong selective filters exerted unconsciously by artificial selection should have resulted in generalised channelling of seedling morphology towards more productive and more herbivore risky phenotypes. This result opens up unexplored opportunities for directional breeding of seedling traits. © 2014 German Botanical Society and The Royal Botanical Society of the Netherlands.
Research and management in a young northern red oak seedling seed orchard

Treesearch

S.E. Schlarbaum; J.L. McConnell; L.R. Barber; R.A. Cox; J.F. Grant; Paul P. Kormanik; T. La Farge; P.L. Lambdin; S.W. Oak; C.K. Proffitt; J.R. Rhea; T. Tibbs

1994-01-01

A northern red oak progeny test was thinned at age 15 to produce a seedling seed orchard. Studies were initiated to determine relationships between acorn production and seed source. Acorn production was observed in 1984-1986 and 1989-1992.Family differences were observed in reproductive maturity. Large differences in size of acorns from the same tree were observed...
Responses of Wound-Inoculated Seedlings of Pinus elliottii var. elliottii and Pinus taeda to Mycelial Cultures Derived from Multople and Singel Basidiospores of Cronartium quercuum f. sp. fusiforme

Treesearch

T. Miller; K.P. Gramacho; R.A. Schmidt; H.V. Amerson; E.G. Kuhlman

1998-01-01

In 1991, a series of experiments was initiated to examine the effectiveness and research value of inoculating 6-week-old seedlings of slash (Pinus elliottii var. elliottii) and loblolly pine (P. raeda) with suspensions of basidiospores of Cronartium quercuum f. sp. fusiforme...
Insects affecting establishment of northern red oak seedlings in central Pennsylvania

Treesearch

J. Galford; L.R. Auchmoody; H.C. Smith; R.S. Walters

1991-01-01

Studies to evaluate the impact of insects on the establishment of advance oak regeneration in Pennsylvania were initiated in 1989. The populations and species of insects feeding on germinating acorns and new seedlings, their activity periods, and the damage caused by these insects were studied in relation to overstory-density (40, 60, and 100 percent relative density)...

Conducting seedling stock type trials: A new approach to an old question

Treesearch

Jeremiah R. Pinto; R. Kasten Dumroese; Anthony S. Davis; Thomas D. Landis

2011-01-01

Seedlings for reforestation and restoration come in many shapes and sizes, i.e., a variety of stocktypes. With so many choices available, land managers commonly ask which stocktype will best meet their management objectives. For years, stocktype studies have been initiated in search of an answer to this question, but few have been done without some degree of...
New sources of adult plant and seedling resistance to Puccinia coronata f. sp. avenae identified among Avena sativa accessions of the national small grains collection

USDA-ARS?s Scientific Manuscript database

Accessions of cultivated oat (A. sativa L.) from the USDA-ARS Small Grains Collection in Aberdeen, ID were characterized for adult plant resistance (APR) and seedling resistance to crown rust, caused by Puccinia coronata f. sp. avenae (Pca). Initially, 607 oat accessions with diverse geographic orig...
Effects of site preparation treatments on early growth and survival of planted longleaf pine (Pinus palustris Mill.) seedlings in North Carolina

Treesearch

Benjamin O. Knapp; G. Geoff Wang; Joan L. Walker; Susan Cohen

2006-01-01

We tested the effects of eight site preparation treatments on early growth and survival of container-grown longleaf pine (Pinus palustris Mill.) seedlings. Treatments included an untreated check, six combinations of two initial vegetation control treatments (chopping or herbicide) with three planting site conditions (flat [no additional treatment],...
Nursery stock quality as an indicator of bottomland hardwood forest restoration success in the Lower Mississippi River Alluvial Valley

Treesearch

Douglass F. Jacobs; Rosa C. Goodman; Emile S. Gardiner; K Frances Salifu; Ronald P. Overton; George Hernandez

2012-01-01

Seedling morphological quality standards are lacking for bottomland hardwood restoration plantings in the Lower Mississippi River Alluvial Valley, USA, which may contribute toward variable restoration success. We measured initial seedling morphology (shoot height, root collar diameter, number of first order lateral roots, fresh mass, and root volume), second year field...
Seven persistent misconceptions about Ocean Nourishment

NASA Astrophysics Data System (ADS)

Jones, I.

2016-02-01

Ian S F Jones Ocean Technology Group University of Sydney, F09 Australia The productivity of the open ocean is dependent on the flow of nutrients most of which are upwelled from the deep ocean. The natural limitation posed by the restricted supply of nutrients in the soil has been overcome in agriculture by supplying mined or manufactured nutrients. This has increased the productivity of the arable land by a factor of five. Purposeful ocean fertilisation, in contrast, has rarely been practiced in part because of a number of concerns about the potential environmental impacts. In some regions of the ocean iron is the limiting nutrient while in the majority of the ocean, the macronutrient nitrogen limits phytoplankton growth. The fertilization with macronutrients, has been termed Ocean Nourishment and has a number of differences to fertilisation by iron. Some misunderstandings arise because analogies of coastal eutrophication and iron fertilisation are uncritically assumed to apply to macronutrient fertilisation. Seven misunderstandings persist and now can be discounted; Export will be low due to enhancement of the microbial loop. Phosphate and silica will need to be supplied. The quantity and cost of nitrogen make carbon sequestration uneconomic Fertilisation with urea encourages dinoflagellates. Size distribution will unsuitable (too small) for zooplankton and herbivorous fish. Fertilization will cause alarming levels of oxygen consumption. Implementation carries large ecological risk. For low fertilisation concentrations, away from shallow water, in a prevailing current, in temperate waters, the seven concerns above can be shown to be mild enough to justify open ocean small scale scientific experimentation.
Developing a regional scale approach for modelling the impacts of fertiliser regime on N2O emissions in Ireland

NASA Astrophysics Data System (ADS)

Zimmermann, Jesko; Jones, Michael

2016-04-01

Agriculture can be significant contributor to greenhouse gas emissions, this is especially prevalent in Ireland where the agricultural sector accounts for a third of total emissions. The high emissions are linked to both the importance of agriculture in the Irish economy and the focus on dairy and beef production. In order to reduce emissions three main categories are explored: (1) reduction of methane emissions from cattle, (2) reduction of nitrous oxide emissions from fertilisation, and (3) fostering the carbon sequestration potential of soils. The presented research focuses on the latter two categories, especially changes in fertiliser amount and composition. Soil properties and climate conditions measured at the four experimental sites (two silage and two spring barley) were used to parameterise four biogeochemical models (DayCent, ECOSSE, DNDC 9.4, and DNDC 9.5). All sites had a range of different fertiliser regimes applied. This included changes in amount (0 to 500 kg N/ha on grassland and 0 to 200 kg N/ha on arable fields), fertiliser type (calcium ammonium nitrate and urea), and added inhibitors (the nitrification inhibitor DCD, and the urease inhibitor Agrotain). Overall, 20 different treatments were applied to the grassland sites, and 17 to the arable sites. Nitrous oxide emissions, measured in 2013 and 2014 at all sites using closed chambers, were made available to validate model results for these emissions. To assess model performance for the daily measurements, the Root Mean Square Error (RMSE) was compared to the measured 95% confidence interval of the measured data (RMSE95). Bias was tested comparing the relative error (RE) the 95 % confidence interval of the relative error (RE95). Preliminary results show mixed model performance, depending on the model, site, and the fertiliser regime. However, with the exception of urea fertilisation and added inhibitors, all scenarios were reproduced by at least one model with no statistically significant total error (RMSE < RMSE95) or bias (RE< RE95). A general trend observed was that model performance declined with increased fertilisation rates. Overall, DayCent showed the best performance, however it does not provide the possibility to model the addition urease inhibitors. The results suggest that modelling changes in fertiliser regime on a large scale may require a multi-model approach to assure best performance. Ultimately, the research aims to develop a GIS based platform to apply such an approach on a regional scale.
Influence of fertilisation with sewage sludge-derived preparation on selected soil properties and prairie cordgrass yield.

PubMed

Ociepa, Ewa; Mrowiec, Maciej; Lach, Joanna

2017-07-01

The aim of the study was to evaluate the effect of using a fertilizer obtained from waste substances on selected physical and chemical properties of soil and biomass yield Spartina pectinate. The fertilizer used for soil (C) fertilisation contained sewage sludge (SS), waste soil fractions of brown coal (BC), brown coal ash (BCA) enriched with mineral potassium (K) fertilizer (C+SS+BC+BCA+K). The composition of the preparation was developed by the authors and adjusted to the quality of the fertilised soil and the individual characteristics of the plant. It was assumed that the preparation should replace expensive conventional fertilisation methods, allow for management of waste substances and improve soil properties, leading to a high yield of Spartina pectinata used as energy crop. The plants were grown on the soil from the Huta Częstochowa steelworks effect zone. The soil was light, with acid reaction (pH KCl =5.5), with small contents of such contaminants as Cd and Zn and elevated Pb content. Based on a three-year pot experiment, the paper presents the results of the examinations concerning the effect of fertilisation on soil pH, hydrolytic acidity, sorptive properties, content of humic acids, organic coal and total nitrogen in soil and crop yielding. The effect of the use of the fertilizer (C+SS+BC+BCA+K) was compared with the use of the sludge (C+SS), sludge with mineral fertilizers (C+SS+NPK), mixture of brown coal and mineral fertilizers (C+BC+NPK) and effect of only mineral fertilizers (C+NPK). Fertilisation with (C+SS+BC+BCA+K) led to the increase in soil pH from 5.5 to 6.0, which is considered sufficient for light soils. The fertilised soil was characterized by sorption capacity of ca. 5.8 cmol(+)/kg, and, after fertilisation with O+W+P, reached the value of ca. 8.0 cmol(+)kg -1 . Consequently the soil can be regarded as of good quality in terms of its capability to store nutrients. The C:N ratio was also extended from 11:1 (control soil) to 14:1 (C+SS+BC+BCA+K). The yield of Spartina pectinata in the first year was 1.6 and in the third year 2.7 times higher in the case of fertilisation with the investigated mixture as compared to the control. Copyright © 2017 Elsevier Inc. All rights reserved.
Effect of nitrification inhibitors (DMPP and 3MP+TZ) on soil nitrous oxide emissions from a sub-tropical vegetable production system in Queensland, Australia

NASA Astrophysics Data System (ADS)

Scheer, Clemens; Deuter, Peter; Firrell, Mary; Rowlings, David; Grace, Peter

2015-04-01

The use of nitrification inhibitors, in combination with ammonium based fertilisers, has been promoted recently as an effective method to reduce nitrous oxide (N2O) emissions from fertilised agricultural fields, whilst increasing yield and nitrogen use efficiency. Vegetable cropping systems are often characterised by high inputs of nitrogen fertiliser and consequently elevated emissions of nitrous oxide (N2O) can be expected. However, to date only limited data is available on the use of nitrification inhibitors in sub-tropical vegetable systems. A field experiment investigated the effect of the nitrification inhibitors (DMPP & 3MP+TZ) on N2O emissions and yield from a typical vegetable production system in sub-tropical Australia. Soil N2O fluxes were monitored continuously over an entire year with a fully automated system. Measurements were taken from three subplots for each treatment within a randomized complete blocks design. There was a significant inhibition effect of DMPP and 3MP+TZ on N2O emissions and soil mineral N content directly following the application of the fertiliser over the vegetable cropping phase. However this mitigation was offset by elevated N2O emissions from the inhibitor treatments over the post-harvest fallow period. Cumulative annual N2O emissions amounted to 1.22 kg-N/ha, 1.16 kg-N/ha, 1.50 kg-N/ha and 0.86 kg-N/ha in the conventional fertiliser (CONV), the DMPP treatment, the 3MP+TZ treatment and the zero fertiliser (0N) respectively. Corresponding fertiliser induced emission factors (EFs) were low with only 0.09 - 0.20% of the total applied fertiliser lost as N2O. There was no significant effect of the nitrification inhibitors on yield compared to the CONV treatment for the three vegetable crops (green beans, broccoli, lettuce) grown over the experimental period. This study highlights that N2O emissions from such vegetable cropping system are primarily controlled by post-harvest emissions following the incorporation of vegetable crop residues into the soil. It also shows that the use of nitrification inhibitors can lead to elevated N2O emissions by storing N in the soil profile that is available to soil microbes during the decomposition of the vegetable residues over the post-harvest phase. Hence the use of nitrification inhibitors in vegetable systems has to be treated carefully and fertiliser rates need to be adjusted to avoid excess soil nitrogen during the postharvest phase.
Effects of glucose and ethylene on root hair initiation and elongation in lettuce (Lactuca sativa L.) seedlings.

PubMed

Harigaya, Wakana; Takahashi, Hidenori

2018-05-01

Root hair formation occurs in lettuce seedlings after transfer to an acidic medium (pH 4.0). This process requires cortical microtubule (CMT) randomization in root epidermal cells and the plant hormone ethylene. We investigated the interaction between ethylene and glucose, a new signaling molecule in plants, in lettuce root development, with an emphasis on root hair formation. Dark-grown seedlings were used to exclude the effect of photosynthetically produced glucose. In the dark, neither root hair formation nor the CMT randomization preceding it occurred, even after transfer to the acidic medium (pH 4.0). Adding 1-aminocyclopropane-1-carboxylic-acid (ACC) to the medium rescued the induction, while adding glucose did not. Although CMT randomization occurred when glucose was applied together with ACC, it was somewhat suppressed compared to that in ACC-treated seedlings. This was not due to a decrease in the speed of randomization, but due to lowering of the maximum degree of randomization. Despite the negative effect of glucose on ACC-induced CMT randomization, the density and length of ACC-induced root hairs increased when glucose was also added. The hair-cell length of the ACC-treated seedlings was comparable to that in the combined-treatment seedlings, indicating that the increase in hair density caused by glucose results from an increase in the root hair number. Furthermore, quantitative RT-PCR revealed that glucose suppressed ethylene signaling. These results suggest that glucose has a negative and positive effect on the earlier and later stages of root hair formation, respectively, and that the promotion of the initiation and elongation of root hairs by glucose may be mediated in an ethylene-independent manner.
Branching of the PIF3 regulatory network in Arabidopsis: roles of PIF3-regulated MIDAs in seedling development in the dark and in response to light.

PubMed

Sentandreu, Maria; Leivar, Pablo; Martín, Guiomar; Monte, Elena

2012-04-01

Plants need to accurately adjust their development after germination in the underground darkness to ensure survival of the seedling, both in the dark and in the light upon reaching the soil surface. Recent studies have established that the photoreceptors phytochromes and the bHLH phytochrome interacting factors PIFs regulate seedling development to adjust it to the prevailing light environment during post-germinative growth. However, complete understanding of the downstream regulatory network implementing these developmental responses is still lacking. In a recent work, published in The Plant Cell, we report a subset of PIF3-regulated genes in dark-grown seedlings that we have named MIDAs (MISREGULATED IN DARK). Analysis of their functional relevance using mutants showed that four of them present phenotypic alterations in the dark, and that each affected a particular facet of seedling development, suggesting organ-specific branching in the signal that PIF3 relays downstream. Furthermore, our results also showed an altered response to light in seedlings with an impaired PIF3/MIDA regulatory network, indicating that these factors might also be essential to initiate and optimize the developmental adjustment of the seedling to the light environment.
Early survival and growth of planted shortleaf pine seedlings as a function of initial size and overstory stocking

Treesearch

John M. Kabrick; Daniel C. Dey; Stephen R. Shifley; Jason L. Villwock

2011-01-01

Shortleaf pine was once abundant throughout the Missouri Ozarks and there is renewed interest in its restoration. Past research suggested that the greatest survival and growth of shortleaf pine seedlings occurred where there was little competition for sunlight. This study, in the oak and oak-pine forests of the Sinkin Experimental Forest in southeastern Missouri,...
Germinant size of jack pine in relation to seed size and geographic origin

Treesearch

C.W. Yeatman

1966-01-01

The initial size of conifer seedlings is closely related to seed size (Hadders 1963), and seed size is a maternal characteristic that is highly subject to environmental modification (Mergen et al. 1964; Righter 1945). The effect of seed weight must be accounted for in critical studies of seedlings which attempt to attribute differences in growth to specific genetic or...
Establishment and Growth of Cherrybark Oak Seedlings Underplanted Beneath a Partial Overstory in a Minor Bottom of Southwestern Arkansas: First Year Results

Treesearch

Emile S. Gardiner; Jimmie L. Yeiser

1999-01-01

Advance regeneration is frequently inadequate to sufficiently restock the oak component of many bottomland stands, especially on productive sites with high levels of competition. We initiated a study near Beime, AR to examine the effects of pre-plant control of Japanese honeysuckle (Lonicera japonica Thunberg) and seedling quality on establishment...
Survival and growth of underplanted northern red oak on mesic sites in Eastern Tennessee: two-year results

Treesearch

Matthew G. Olson; Wayne K. Clatterbuck; Scott E. Schlarbaum

2006-01-01

As part of a replicated oak regeneration study initiated at the University of Tennesseeâs Oak Ridge Forestry Experiment Station, 180 northern red oak (Quercus rubra L.) seedlings were allocated equally among three no-cut control stands, which provided an opportunity to chart the survival and growth of understory planted oak seedlings across several...
Nursery practices influence seedling morphology, field performance, and cost efficiency of containerized cherrybark oak.

Treesearch

Kirk D. Howell; Timothy B. Harrkngton

2004-01-01

To quantify effects of nursery practices on seedling cost and performance, cherrybark oaks (Quercus pagoda L.) were grown in three container sizes (170, 650, or 1,250 cm z) with or without fertilization and then planted Dec. 1995 at a site near Milledgeville, GA, with or without removal of container soil. Initial size, biomass, and leaf area of...
The effect of a multifaceted empowerment strategy on decision making about the number of embryos transferred in in vitro fertilisation: randomised controlled trial.

PubMed

van Peperstraten, Arno; Nelen, Willianne; Grol, Richard; Zielhuis, Gerhard; Adang, Eddy; Stalmeier, Peep; Hermens, Rosella; Kremer, Jan

2010-09-30

To evaluate the effects of a multifaceted empowerment strategy on the actual use of single embryo transfer after in vitro fertilisation. Randomised controlled trial. Five in vitro fertilisation clinics in the Netherlands. 308 couples (women aged <40) on the waiting list for a first in vitro fertilisation cycle. The multifaceted strategy aimed to empower couples in deciding how many embryos should be transferred. The strategy consisted of a decision aid, support of a nurse specialising in in vitro fertilisation, and the offer of reimbursement by way of an extra treatment cycle. The control group received standard care for in vitro fertilisation. Use of single embryo transfer in the first and second treatment cycles as well as decision making variables and costs of the empowerment strategy. After the first treatment cycle, single embryo transfer was used by 43% (65/152) of couples in the intervention group and 32% (50/156) in the control group (difference 11%, 95% confidence interval 0% to 22%; P=0.05). After the second treatment cycle, single embryo transfer was used by 26% (14/154) of couples in the intervention group compared with 16% (8/51) in the control group (difference 10%, -6% to 26%; P=0.20). Compared with couples receiving standard care, those receiving the empowerment strategy had significantly higher empowerment and knowledge levels but no differences in anxiety levels. Mean total savings per couple in the intervention group were calculated to be €169.75 (£146.77; $219.12). A multifaceted empowerment strategy encouraged use of single embryo transfer, increased patients' knowledge, reduced costs, and had no effect on levels of anxiety or depression. This strategy could therefore be an important tool to reduce the twin pregnancy rate after in vitro fertilisation. This trial did not, however, demonstrate the anticipated 25% difference in use of single embryo transfer of the power calculation. ClinicalTrials.gov NCT00315029.
Effects of long-term fertilisation on aggregates and dynamics of soil organic carbon in a semi-arid agro-ecosystem in China

PubMed Central

Zhang, Jiaoyang; Sun, Caili; Xue, Sha

2018-01-01

Background Long-term fertilisation has a large influence on soil physical and chemical properties in agro-ecosystems. The effects on the distribution of aggregates, however, are not fully understood. We determined the dynamic change of the distribution of aggregates and soil organic carbon (SOC) content over time in a long-term field experiment established in 1998 on the Loess Plateau of China and illustrated the relationship between them. Methods We determined SOC content and the distribution of aggregates in nine fertiliser treatments: manure (M); nitrogen (N); phosphorus (P); M and N; M, N, and P; M and P; N and P; bare land; and an unfertilised control. These parameters were then used for a path analysis and to analyse the fractal dimension (Dv). Results The organic fertiliser increased SOC content. The proportions of 0.1–0.25 mm microaggregates and 0.25–0.5 mm macroaggregates were higher and the proportion of the 0.01–0.05 mm size class of the silt + clay fraction was lower in the treatments receiving organic fertiliser (M, MN, MNP, and MP) than that in the control, indicating that the addition of organic fertiliser promoted aggregation. The distribution of aggregates characterised by their fractal dimension (Dv), however, did not differ among the treatments. Discussion Dv was strongly correlated with the proportion of the <0.002 mm size class of the silt + clay fraction that did not differ significantly among the treatments. The change in the distribution of aggregates was strongly correlated with SOC content, which could produce organic polymer binding agents to increase the proportion of larger particles. Long-term application of organic fertiliser is thus necessary for the improvement and maintenance of soil quality in semi-arid agricultural land when residues are removed. PMID:29844955
Combining a weed traits database with a population dynamics model predicts shifts in weed communities.

PubMed

Storkey, J; Holst, N; Bøjer, O Q; Bigongiali, F; Bocci, G; Colbach, N; Dorner, Z; Riemens, M M; Sartorato, I; Sønderskov, M; Verschwele, A

2015-04-01

A functional approach to predicting shifts in weed floras in response to management or environmental change requires the combination of data on weed traits with analytical frameworks that capture the filtering effect of selection pressures on traits. A weed traits database (WTDB) was designed, populated and analysed, initially using data for 19 common European weeds, to begin to consolidate trait data in a single repository. The initial choice of traits was driven by the requirements of empirical models of weed population dynamics to identify correlations between traits and model parameters. These relationships were used to build a generic model, operating at the level of functional traits, to simulate the impact of increasing herbicide and fertiliser use on virtual weeds along gradients of seed weight and maximum height. The model generated 'fitness contours' (defined as population growth rates) within this trait space in different scenarios, onto which two sets of weed species, defined as common or declining in the UK, were mapped. The effect of increasing inputs on the weed flora was successfully simulated; 77% of common species were predicted to have stable or increasing populations under high fertiliser and herbicide use, in contrast with only 29% of the species that have declined. Future development of the WTDB will aim to increase the number of species covered, incorporate a wider range of traits and analyse intraspecific variability under contrasting management and environments.
The endogenous hormones in soybean seedlings under the joint actions of rare earth element La(III) and ultraviolet-B stress.

PubMed

Peng, Qi; Zhou, Qing

2009-12-01

The dynamic state of endogenous hormone content in soybean seedlings was investigated for a further demonstration of alleviating the damage of the ultraviolet ultraviolet-B (UV-B) radiation in the La(III)-treated soybean seedlings under UV-B stress. Using hydroponics culture, the effects of lanthanum(III) on the contents of endogenous hormone under elevated ultraviolet-B radiation (280–320 nm) was studied. The results showed that the content of indole-3-acetic acid (IAA) in soybean seedlings decreased initially and then increased when the seedlings underwent UV-B treatment during the stress and convalescent period; this was compared with a control; acetic acid oxidase (IAAO) activity increased at first (first to fifth day) and then decreased (sixth to 11th day). A similar change of abscisic acid content and IAAO content in soybean seedlings occurred; gibberellic acid (GA) content decreased during the experiment compared with control. The content of IAA and GA in soybean seedlings with La(III) + UV-B treatment was higher than those of UV-B treatment; IAAO activity and GA content in soybean seedlings with La (III) + UV-B treatment were lower than those of UV-B treatment. It suggested that the regulative effect of La(III) at the optimum concentration on endogenous hormone improved the ability of plant stress resistance, and its protective effect against low UV-B radiation was superior to high UV-B radiation. The defensive effect of La(III) on soybean seedlings under UV-B stress was carried out on the layer of defense system.
Early root cap development and graviresponse in white clover (Trifolium repens) grown in space and on a two-axis clinostat

NASA Technical Reports Server (NTRS)

Smith, J. D.; Staehelin, L. A.; Todd, P.

1999-01-01

White clover (Trifolium repens) was germinated and grown in microgravity aboard the Space Shuttle (STS-60, 1994; STS-63, 1995), on Earth in stationary racks and in a slow-rotating two-axis clinostat. The objective of this study was to determine if normal root cap development and early plant gravity responses were dependent on gravitational cues. Seedlings were germinated in space and chemically fixed in orbit after 21, 40, and 72 h. Seedlings 96 h old were returned viable to earth. Germination and total seedling length were not dependent on gravity treatment. In space-flown seedlings, the number of cell stories in the root cap and the geometry of central columella cells did not differ from those of the Earth-grown seedlings. The root cap structure of clinorotated plants appeared similar to that of seedlings from microgravity, with the exception of three-day rotated plants, which displayed significant cellular damage in the columella region. Nuclear polarity did not depend on gravity; however, the positions of amyloplasts in the central columella cells were dependent on both the gravity treatment and the age of the seedlings. Seedlings from space, returned viable to earth, responded to horizontal stimulation as did 1 g controls, but seedlings rotated on the clinostat for the same duration had a reduced curvature response. This study demonstrates that initial root cap development is insensitive to either chronic clinorotation or microgravity. Soon after differentiation, however, clinorotation leads to loss of normal root cap structure and plant graviresponse while microgravity does not.

Expression of stress-related genes in zebrawood (Astronium fraxinifolium, Anacardiaceae) seedlings following germination in microgravity

PubMed Central

Inglis, Peter W.; Ciampi, Ana Y.; Salomão, Antonieta N.; Costa, Tânia da S.A.; Azevedo, Vânia C.R.

2014-01-01

Seeds of a tropical tree species from Brazil, Astronium fraxinifolium, or zebrawood, were germinated, for the first time in microgravity, aboard the International Space Station for nine days. Following three days of subsequent growth under normal terrestrial gravitational conditions, greater root length and numbers of secondary roots was observed in the microgravity-treated seedlings compared to terrestrially germinated controls. Suppression subtractive hybridization of cDNA and EST analysis were used to detect differential gene expression in the microgravity-treated seedlings in comparison to those initially grown in normal gravity (forward subtraction). Despite their return to, and growth in normal gravity, the subtracted library derived from microgravity-treated seedlings was enriched in known microgravity stress-related ESTs, corresponding to large and small heat shock proteins, 14-3-3-like protein, polyubiquitin, and proteins involved in glutathione metabolism. In contrast, the reverse-subtracted library contained a comparatively greater variety of general metabolism-related ESTs, but was also enriched for peroxidase, possibly indicating the suppression of this protein in the microgravity-treated seedlings. Following continued growth for 30 days, higher concentrations of total chlorophyll were detected in the microgravity-exposed seedlings. PMID:24688295
How the use of nitrogen fertiliser may switch plant suitability for aphids: the case of Miscanthus, a promising biomass crop, and the aphid pest Rhopalosiphum maidis.

PubMed

Bogaert, Florent; Chesnais, Quentin; Catterou, Manuella; Rambaud, Caroline; Doury, Géraldine; Ameline, Arnaud

2017-08-01

The use of nitrogen fertiliser in agrosystems can alter plant nitrogen and consequently improve nutrient availability for herbivores, potentially leading to better performance for herbivores and higher pest pressure in the field. We compared, in laboratory conditions, the effects of nitrogen fertilisation on a promising biomass crop, Miscanthus × giganteus, and its parents M. sinensis and M. sacchariflorus. The plant-mediated effects were compared on the second trophic level, the green corn leaf aphid Rhopalosiphum maidis. Results showed that the biomass and leaf C:N ratio of M. sinensis plants treated with nitrogen fertiliser were significantly greater than those of non-treated plants. As regards M. × giganteus and M. sacchariflorus, the only reported change was a significantly smaller leaf C:N ratio for treated M. sacchariflorus compared with non-treated plants. Surprisingly, nitrogen fertilisation had opposite effects on plant-herbivore interactions. Following nitrogen treatments, M. sinensis was less suitable in terms of intrinsic rate of increase for R. maidis, the feeding behaviour of which was negatively affected, while M. sacchariflorus and M. × giganteus exhibited greater suitability in terms of aphid weight. Nitrogen fertilisation had contrasting effects on the three species of Miscanthus plants. These effects cascaded up to the second trophic level, R. maidis aphid pests, either through a modification of their weight or demographic parameters. The implications of these results were discussed in the context of agricultural sustainability and intensive production practices. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.
Cytokine expression in the seminal plasma and its effects on fertilisation rates in an IVF cycle.

PubMed

Seshadri, S; Bates, M; Vince, G; Jones, D I Lewis

2011-12-01

Cytokines are released by various immunocompetent cell subsets in the male urogenital tract and are thought to affect sperm cell function and reproductive process. The aim of the study was to evaluate the levels and a possible role of seven seminal plasma cytokines with fertilisation rates in men attending an in vitro fertilisation (IVF) programme. A total of 36 men of couples who were undergoing traditional IVF in a regional reproductive medicine unit were recruited into this prospective study. Cytokines such as interleukin (IL)-6, IL-8, IL-10, IL-11, IL-12, tumour necrosis factor alpha (TNF-α) and interferon gamma (IFN-γ) in the seminal plasma were determined using enzyme linked immunosorbent assay. IL-6, IL-8, IL-10, IL-11 and IFN-γ were detected in all samples. IL-12, and TNF-α were detected in most samples. Levels of IL-11 were significantly higher in the good fertiliser group (P ≤ 0.05). Positive correlation between cytokines such as IL-6 and IL-8 (P < 0.03), IL-10 and IL-11 (P < 0.001) and IFN-γ and IL-10 and IL-11 (P < 0.04 and P < 0.0001 respectively) were found. Our study confirms that the six cytokines other than IL-11 do not affect spermatozoon-oocyte interaction and fertilisation rates in IVF. IL-11 could have a role in the fertilising capacity of the spermatozoa. Significant correlation exists among these cytokines which shows that cytokines rarely act in isolation but rather in a network. © 2011 Blackwell Verlag GmbH.
Characteristics of differently stabilised soil organic carbon fractions in relation to long-term fertilisation in Brown Earth of Northeast China.

PubMed

Xu, Xiangru; Zhang, Wenju; Xu, Minggang; Li, Shuangyi; An, Tingting; Pei, Jiubo; Xiao, Jing; Xie, Hongtu; Wang, Jingkuan

2016-12-01

Long-term use of artificial fertiliser has a significant impact on soil organic carbon (SOC). We used physical-chemical fractionation methods to assess the impact of long-term (26years) fertilisation in a maize cropping system developed on Brown Earth in Northeast China. Plot treatments consisted of control (CK); nitrogen (N) fertiliser (N2); low-level organic manure combined with inorganic N and phosphorus (P) fertiliser (M1N1P1); medium-level organic manure combined with inorganic N fertiliser (M2N2); and high-level organic manure combined with inorganic N and P fertiliser (M4N2P1). Our objectives were to (1) determine the contents of and variations in the SOC fractions; (2) explore the relationship between total SOC and its fractions. In treatments involving organic manure (M1N1P1, M2N2, and M4N2P1), total SOC and physically protected microaggregate (μagg) and μagg occluded particulate organic carbon (iPOC) contents increased by 9.9-58.9%, 1.3-34.7%, 29.5-127.9% relative to control, respectively. But there no significant differences (P>0.05) were detected for the chemically, physically-chemically, and physically-biochemically protected fractions among the M1N1P1, M2N2, and M4N2P1 treatments. Regression analysis revealed that there was a linear positive correlation between SOC and the unprotected coarse particulate organic carbon (cPOC), physically protected μagg, and iPOC fractions (P<0.05). However, physically-chemically, and physically-biochemically protected fractions responded negatively to SOC content. The highest rate of C accumulation among the SOC fractions occurred in the cPOC fraction, which accounted for as much as 32% of C accumulation as total SOC increased, suggesting that cPOC may be the most sensitive fraction to fertiliser application. We found that treatments had no effect on C levels in H-μsilt and NH-μsilt, indicating that the microaggregated silt C-fractions may have reached a steady state in terms of C saturation in the Brown Earth of Northeast China. Copyright © 2016 Elsevier B.V. All rights reserved.
Is There a Role for the Apex in Shoot Geotropism?

PubMed Central

Hart, James W.; Macdonald, Ian R.

1984-01-01

Experiments with horizontal etiolated sunflower (Helianthus annuus L.) seedlings supported centrally such that both apical and basal ends are free to react to geostimulus, revealed that the apical end commences curvature 1 to 2 hours earlier than the basal end. The later curvature in the basal region is a consequence of the absence of growth in the initial period rather than merely slower growth. A comparison of zonal growth rates in a vertical and a horizontal seedling confirmed that geostimulus induces a renewal of growth in a region where growth had ceased. Removing the apical half of the hypocotyl showed that the curvature resulting from this growth initiation in the basal region is dependent on attachment to the apical region. Evidence that this dependence is unlikely to be due to energy deficiency is adduced. The prior response of the apical end to geostimulus and the apically dependent later initiation of new growth in the basal region are compatible with the delay inherent in message transport from apex to base and are considered as evidence for apical involvement in the totality of the seedling's georesponse. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 PMID:16663410
Pelleted organo-mineral fertilisers from composted pig slurry solids, animal wastes and spent mushroom compost for amenity grasslands.

PubMed

Rao, Juluri R; Watabe, Miyuki; Stewart, T Andrew; Millar, B Cherie; Moore, John E

2007-01-01

In Ireland, conversion of biodegradable farm wastes such as pig manure spent mushroom compost and poultry litter wastes to pelletised fertilisers is a desirable option for farmers. In this paper, results obtained from the composting of pig waste solids (20% w/w) blended with other locally available biodegradable wastes comprising poultry litter (26% w/w), spent mushroom compost (26% w/w), cocoa husks (18% w/w) and moistened shredded paper (10% w/w) are presented. The resulting 6-mo old 'mature' composts had a nutrient content of 2.3% total N, 1.6% P and 3.1% K, too 'low' for direct use as an agricultural fertiliser. Formulations incorporating dried blood or feather meal amendments enriched the organic N-content, reduced the moisture in mature compost mixtures and aided the granulation process. Inclusion of mineral supplements viz., sulphate of ammonia, rock phosphate and sulphate of potash, yielded slow release fertilisers with nutrient N:P:K ratios of 10:3:6 and 3:5:10 that were suited for amenity grasslands such as golf courses for spring or summer application and autumn dressing, respectively. Rigorous microbiological tests carried out throughout the composting, processing and pelletising phases indicated that the formulated organo-mineral fertilisers were free of vegetative bacterial pathogens.
Nitrogen fertilisation increases biogenic amines and amino acid concentrations in Vitis vinifera var. Riesling musts and wines.

PubMed

Smit, Inga; Pfliehinger, Marco; Binner, Antonie; Großmann, Manfred; Horst, Walter J; Löhnertz, Otmar

2014-08-01

Wines rich in biogenic amines can cause adverse health effects to the consumer. Being nitrogen-containing substances, the amount of amines in wines might be strongly influenced by the rate of nitrogen fertiliser application during grape production. The aim of this work was to evaluate the effect of nitrogen fertilisation in the vineyard on the formation of biogenic amines in musts and wines. In a field experiment which compared unfertilised and fertilised (60 and 150 kg N ha(-1)) vines over two separate years, the total amine concentrations in must and wine increased. The latter was due to an increase of individual amines such as ethylamine, histamine, isopentylamine, phenylethylamine and spermidine in the musts and wines with the nitrogen application. Furthermore, the fermentation process increased the concentration of histamine and ethylamine in most of the treatments, while spermidine, spermine and isopentylamine concentrations generally decreased. Throughout both vintages, the concentrations of tyramine and histamine of the investigated musts and wines never reached detrimental levels to the health of non-allergenic people. Nitrogen fertilisation has a significant effect on amines formation in musts and wines. Furthermore, during fermentation, ethylamine and histamine increased while other amines were presumably serving as N sources during fermentation. © 2013 Society of Chemical Industry.
Environmental factors limiting fertilisation and larval success in corals

NASA Astrophysics Data System (ADS)

Woods, Rachael M.; Baird, Andrew H.; Mizerek, Toni L.; Madin, Joshua S.

2016-12-01

Events in the early life history of reef-building corals, including fertilisation and larval survival, are susceptible to changes in the chemical and physical properties of sea water. Quantifying how changes in water quality affect these events is therefore important for understanding and predicting population establishment in novel and changing environments. A review of the literature identified that levels of salinity, temperature, pH, suspended sediment, nutrients and heavy metals affect coral early life-history stages to various degrees. In this study, we combined published experimental data to determine the relative importance of sea water properties for coral fertilisation success and larval survivorship. Of the water properties manipulated in experiments, fertilisation success was most sensitive to suspended sediment, copper, salinity, phosphate and ammonium. Larval survivorship was sensitive to copper, lead and salinity. A combined model was developed that estimated the joint probability of both fertilisation and larval survivorship in sea water with different chemical and physical properties. We demonstrated the combined model using water samples from Sydney and Lizard Island in Australia to estimate the likelihood of larvae surviving through both stages of development to settlement competency. Our combined model could be used to recommend targets for water quality in coastal waterways as well as to predict the potential for species to expand their geographical ranges in response to climate change.
Medicago sativa--Sinorhizobium meliloti Symbiosis Promotes the Bioaccumulation of Zinc in Nodulated Roots.

PubMed

Zribi, Kais; Nouairi, Issam; Slama, Ines; Talbi-Zribi, Ons; Mhadhbi, Haythem

2015-01-01

In this study we investigated effects of Zn supply on germination, growth, inorganic solutes (Zn, Ca, Fe, and Mg) partitioning and nodulation of Medicago sativa This plant was cultivated with and without Zn (2 mM). Treatments were plants without (control) and with Zn tolerant strain (S532), Zn intolerant strain (S112) and 2 mM urea nitrogen fertilisation. Results showed that M. sativa germinates at rates of 50% at 2 mM Zn. For plants given nitrogen fertilisation, Zn increased plant biomass production. When grown with symbionts, Zn supply had no effect on nodulation. Moreover, plants with S112 showed a decrease of shoot and roots biomasses. However, in symbiosis with S532, an increase of roots biomass was observed. Plants in symbiosis with S. meliloti accumulated more Zn in their roots than nitrogen fertilised plants. Zn supply results in an increase of Ca concentration in roots of fertilised nitrogen plants. However, under Zn supply, Fe concentration decreased in roots and increased in nodules of plants with S112. Zn supply showed contrasting effects on Mg concentrations for plants with nitrogen fertilisation (increase) and plants with S112 (decrease). The capacity of M. sativa to accumulate Zn in their nodulated roots encouraged its use in phytostabilisation processes.
Quality of white cabbage yield and potential risk of ground water nitrogen pollution, as affected by nitrogen fertilisation and irrigation practices.

PubMed

Maršić, Nina Kacjan; Sturm, Martina; Zupanc, Vesna; Lojen, Sonja; Pintar, Marina

2012-01-15

The effect of different fertilisation (broadcast solid NPK application and fertigation with water-soluble fertiliser) and irrigation practices (sprinkler and drip irrigation) on yield, the nitrate content in cabbage (Brassica oleracea var. capitata L.) and the cabbage N uptake was detected, in order to assess the potential risk for N losses, by cultivation on sandy-loam soil. The N rate applied on the plots was 200 kg N ha(-1). The highest yield (93 t ha(-1)) and nitrate content (1256 mg kg(-1) DW) were found with treatments using broadcast fertilisation and sprinkler irrigation. On those plots the negative N balance (-30 kg N ha(-1)) was recorded, which comes mainly from the highest crop N uptake (234 kg N ha(-1)) indicating the lowest potential for N losses. In terms of yield quality and the potential risk for N losses, broadcast fertilisation combined with sprinkler irrigation proved to be the most effective combination among the tested practices under the given experimental conditions. The importance of adequate irrigation is also evident, namely in plots on which 50% drip irrigation was applied, the lowest yield was detected and according to the positive N balance, a higher potential for N losses is expected. Copyright © 2011 Society of Chemical Industry.
Adding Value to Ash and Digestate (AVAnD). AN Integrated Overview of the Effects of Ash and Digestate Blends on the Soil-Plant System.

NASA Astrophysics Data System (ADS)

Lag-Brotons, Alfonso; Marshall, Rachel; Herbert, Ben; Hurst, Lois; Ostle, Nick; Dodd, Ian C.; Quinton, John; Surridge, Ben; Aiouache, Farid; Semple, Kirk T.

2017-04-01

Resource recovery from waste could play a central role in strategies tackling current worldwide sustainability problems. Focusing on the agricultural sector, waste streams represent an opportunity to break the cycle of nutrients depletion (exported with crop biomass) and incorporation by non-sustainable means such the use of inorganic fertilisers (either finite and/or highly energy intensive in their production). In this sense, digestate [D], from anaerobic digestion, and biomass ash [A], from incineration, are especially valuable since they supply, amongst other nutrients, nitrogen [N] and phosphorus [P], respectively. Whilst these waste streams could be highly heterogeneous, in general terms they present a complementary nutritional profile which could be exploited for the production of alternative fertilisers. This is precisely the overarching aim of the "Adding Value to Ash and Digestate [AVAnD]" project: the identification of a novel nutrient-recycling pathway to maximise soil quality and crop productivity utilising waste streams derived from bioenergy production. However, the application to land of novel recycled and recovered products entails the assessment of the biological and chemical interactions and the implications for ecosystems, to determine desirable and detrimental effects that might arise. Therefore, we aim to provide an insight on the AVAnD project and briefly describe and discuss some of the findings obtained so far. Experiments were carried out at different scales and under different conditions using two different digestates ([D1], [D2]) and two ash fractions (fly [A1] and bottom [A2]). The main factor considered was fertiliser type including A/D blends, A & D alone, no fertilisation and inorganic fertilisers. Fertilisation target (63/60 kg N/P2O5 per ha) was the same across the different fertiliser materials. Aspects covered included nutrient availability (N-, P- forms), soil properties (DOC, pH, EC), greenhouse gas emissions (CO2, N2O) and plant traits (above-ground biomass, tissue elemental concentration). In a glasshouse pot experiment using a neutral loam soil that compared A/D blends and inorganic fertilisers, no significant differences on wheat biomass, tiller number and leaf areaand plant elemental composition (P, Mg, Ca, K, Mn, Na) were observed. Plant nutrient uptake behaved similarly, yet ash-based treatments had lower Mn uptake. Concerning soil properties, increased EC was primarily driven by D and secondarily by A. Digestate-based treatments lowered soil pH while A increased pH, with blending having a moderate effect. D1-based treatments primarily and A1-based treatments secondarily had higher nitrate concentrations. Based on the aforementioned statements, D1A1 was considered a suitable amendment to be used as an inorganic fertiliser replacement for wheat.
Antioxidant capacity of flavonoid in soybean seedlings under the joint actions of rare earth element La(III) and ultraviolet-B stress.

PubMed

Peng, Qi; Zhou, Qing

2009-01-01

The dynamic state of antioxidant capacity of flavonoid was investigated for a further demonstration of alleviating the damage of the ultraviolet (UV)-B radiation in the La-treated soybean seedlings under UV-B stress. Using hydroponics culture, the effects of lanthanum on the contents of flavonoid and its ability of antioxidant under elevated ultraviolet-B radiation (280-320 nm) was studied. The results showed flavonoid content in soybean seedlings with UV-B treatment during the stress and convalescent period was increased initially and then decreased, compared with control. Membrane permeability and MDA contents increase at first (first to fifth day) and then decrease (6th-11th day). A similar change of flavonoid content and clearance of flavonoid scavenging O2- and *OH in soybean seedlings occurred. Flavonoid content and ability of flavonoid scavenging O2- and *OH in soybean seedlings with La(III) + UV-B treatment were higher than those of UV-B treatment. Meanwhile, membrane permeability and MDA contents in soybean seedlings were lower than those of UV-B treatment. Compared with control, phenylalanine content in soybean seedlings with UV-B treatment is depressed, phenylalanine content in soybean seedlings with La(III) treatment was enhanced. However, phenylalanine content in La(III) + UV-B treatment is not decreased but slightly increased, compared with UV-B treatment. It suggested that the regulative effect of La(III) of the optimum concentration on flavonoid improved the metabolism of ROS, diminished the concentration of MDA and maintained normal plasma membrane permeability, and that its protective effect against low UV-B radiation is superior to that of high UV-B radiation. The defensive effect of La(III) on soybean seedlings under UV-B stress is carried out on the layer of defense system.
Two genetically separable phases of growth inhibition induced by blue light in Arabidopsis seedlings

NASA Technical Reports Server (NTRS)

Parks, B. M.; Cho, M. H.; Spalding, E. P.; Evans, M. L. (Principal Investigator)

1998-01-01

High fluence-rate blue light (BL) rapidly inhibits hypocotyl growth in Arabidopsis, as in other species, after a lag time of 30 s. This growth inhibition is always preceded by the activation of anion channels. The membrane depolarization that results from the activation of anion channels by BL was only 30% of the wild-type magnitude in hy4, a mutant lacking the HY4 BL receptor. High-resolution measurements of growth made with a computer-linked displacement transducer or digitized images revealed that BL caused a rapid inhibition of growth in wild-type and hy4 seedlings. This inhibition persisted in wild-type seedlings during more than 40 h of continuous BL. By contrast, hy4 escaped from the initial inhibition after approximately 1 h of BL and grew faster than wild type for approximately 30 h. Wild-type seedlings treated with 5-nitro-2-(3-phenylpropylamino)-benzoic acid, a potent blocker of the BL-activated anion channel, displayed rapid growth inhibition, but, similar to hy4, these seedlings escaped from inhibition after approximately 1 h of BL and phenocopied the mutant for at least 2.5 h. The effects of 5-nitro-2-(3-phenylpropylamino)-benzoic acid and the HY4 mutation were not additive. Taken together, the results indicate that BL acts through HY4 to activate anion channels at the plasma membrane, causing growth inhibition that begins after approximately 1 h. Neither HY4 nor anion channels appear to participate greatly in the initial phase of inhibition.
Phenylalanine Is Required to Promote Specific Developmental Responses and Prevents Cellular Damage in Response to Ultraviolet Light in Soybean (Glycine max) during the Seed-to-Seedling Transition

PubMed Central

Sullivan, Joe H.; Muhammad, DurreShahwar; Warpeha, Katherine M.

2014-01-01

UV-radiation elicits a suite of developmental (photomorphogenic) and protective responses in plants, but responses early post-germination have received little attention, particularly in intensively bred plants of economic importance. We examined germination, hypocotyl elongation, leaf pubescence and subcellular responses of germinating and/or etiolated soybean (Glycine max (L.) Merr.) seedlings in response to treatment with discrete wavelengths of UV-A or UV-B radiation. We demonstrate differential responses of germinating/young soybean seedlings to a range of UV wavelengths that indicate unique signal transduction mechanisms regulate UV-initiated responses. We have investigated how phenylalanine, a key substrate in the phenylpropanoid pathway, may be involved in these responses. Pubescence may be a key location for phenylalanine-derived protective compounds, as UV-B irradiation increased pubescence and accumulation of UV-absorbing compounds within primary leaf pubescence, visualized by microscopy and absorbance spectra. Mass spectrometry analysis of pubescence indicated that sinapic esters accumulate in the UV-irradiated hairs compared to unirradiated primary leaf tissue. Deleterious effects of some UV-B wavelengths on germination and seedling responses were reduced or entirely prevented by inclusion of phenylalanine in the growth media. Key effects of phenylalanine were not duplicated by tyrosine or tryptophan or sucrose, nor is the specificity of response due to the absorbance of phenylalanine itself. These results suggest that in the seed-to-seedling transition, phenylalanine may be a limiting factor in the development of initial mechanisms of UV protection in the developing leaf. PMID:25549094
Long-Term Effect of Crop Rotation and Fertilisation on Bioavailability and Fractionation of Copper in Soil on the Loess Plateau in Northwest China

PubMed Central

Zang, Yifei; Wei, Xiaorong; Hao, Mingde

2015-01-01

The bioavailability and fractionation of Cu reflect its deliverability in soil. Little research has investigated Cu supply to crops in soil under long-term rotation and fertilisation on the Loess Plateau. A field experiment was conducted in randomized complete block design to determine the bioavailability and distribution of Cu fractions in a Heilu soil (Calcaric Regosol) after 18 years of rotation and fertilisation. The experiment started in 1984, including five cropping systems (fallow control, alfalfa cropping, maize cropping, winter wheat cropping, and grain-legume rotation of pea/winter wheat/winter wheat + millet) and five fertiliser treatments (unfertilised control, N, P, N + P, and N + P + manure). Soil samples were collected in 2002 for chemical analysis. Available Cu was assessed by diethylene triamine pentaacetic acid (DTPA) extraction, and Cu was fractionated by sequential extraction. Results showed that DTPA-Cu was lower in cropping systems compared with fallow control. Application of fertilisers resulted in no remarkable changes in DTPA-Cu compared with unfertilised control. Correlation and path analyses revealed that soil pH and CaCO3 directly affected Cu bioavailability, whereas available P indirectly affected Cu bioavailability. The concentrations of Cu fractions (carbonate and Fe/Al oxides) in the plough layer were lower in cropping systems, while the values in the plough sole were higher under grain-legume rotation relative to fallow control. Manure with NP fertiliser increased Cu fractions bound to organic matter and minerals in the plough layer, and its effects in the plough sole varied with cropping systems. The direct sources (organic-matter-bound fraction and carbonate-bound fraction) of available Cu contributed much to Cu bioavailability. The mineral-bound fraction of Cu acted as an indicator of Cu supply potential in the soil. PMID:26694965
Long-Term Effect of Crop Rotation and Fertilisation on Bioavailability and Fractionation of Copper in Soil on the Loess Plateau in Northwest China.

PubMed

Zang, Yifei; Wei, Xiaorong; Hao, Mingde

2015-01-01

The bioavailability and fractionation of Cu reflect its deliverability in soil. Little research has investigated Cu supply to crops in soil under long-term rotation and fertilisation on the Loess Plateau. A field experiment was conducted in randomized complete block design to determine the bioavailability and distribution of Cu fractions in a Heilu soil (Calcaric Regosol) after 18 years of rotation and fertilisation. The experiment started in 1984, including five cropping systems (fallow control, alfalfa cropping, maize cropping, winter wheat cropping, and grain-legume rotation of pea/winter wheat/winter wheat + millet) and five fertiliser treatments (unfertilised control, N, P, N + P, and N + P + manure). Soil samples were collected in 2002 for chemical analysis. Available Cu was assessed by diethylene triamine pentaacetic acid (DTPA) extraction, and Cu was fractionated by sequential extraction. Results showed that DTPA-Cu was lower in cropping systems compared with fallow control. Application of fertilisers resulted in no remarkable changes in DTPA-Cu compared with unfertilised control. Correlation and path analyses revealed that soil pH and CaCO3 directly affected Cu bioavailability, whereas available P indirectly affected Cu bioavailability. The concentrations of Cu fractions (carbonate and Fe/Al oxides) in the plough layer were lower in cropping systems, while the values in the plough sole were higher under grain-legume rotation relative to fallow control. Manure with NP fertiliser increased Cu fractions bound to organic matter and minerals in the plough layer, and its effects in the plough sole varied with cropping systems. The direct sources (organic-matter-bound fraction and carbonate-bound fraction) of available Cu contributed much to Cu bioavailability. The mineral-bound fraction of Cu acted as an indicator of Cu supply potential in the soil.
Nitrate in waters from sewage-sludge amended lysimeters.

PubMed

Jones, R L; Hinesly, T D

1988-01-01

Nitrate nitrogen was measured in runoff and tile-drainage during two years of operation of instrumented, large-scale lysimeters planted to corn (Zea mays L.) and amended with sewage sludge which was applied at rates supplying total N amounting to 2292 kg ha(-) in 1972 and 3286 kg ha(-1) in 1973. Other lysimeters were amended with inorganic fertiliser at the rate of 336 kg N ha(-1) year(-1). Annual losses in runoff and tile-drainage from sludge treatments were 0.9 and 5.1 and 371 and 663 kg NO(3)(-)-N ha(-1). Losses from lysimeters treated with inorganic fertiliser were 1.1 and 3.3 kg NO(3)(-)-N ha(-1) year(-1) in runoff and 31 and 79 kg NO(3)(-)-N ha(-1) year(-1) in tile-drainage. Given the nitrogen inputs accounted for in the study design, unaccounted for losses of 1800 to 2400 kg ha(-1) year(-1) were calculated for sludge and 277 kg ha(-1) year(-1) for inorganic fertiliser treatments. For one year there was a 300 kg ha(-1) increase in N in the lysimeters receiving inorganic fertiliser. Median NO(3)(-)-N concentrations ranged from 8.9 to 14.0 mg litre(-1) in runoff from sludge-treated lysimeters and 3.6 to 5.9 mg litre(-1) in runoff from lysimeters receiving inorganic fertiliser. In tile-drainage the median NO(3)(-)-N concentrations were 148 to 223 mg litre(-1) and 24 to 44 mg litre(-1) for sludge and inorganic fertiliser treatments, respectively. Highest runoff levels occurred in early summer storms, whereas highest tile-drainage concentrations occurred in late winter and early spring.
A lysimeter study of nitrate leaching, optimum fertilisation rate and growth responses of corn (Zea mays L.) following soil amendment with water-saving super-absorbent polymer.

PubMed

Islam, M Robiul; Mao, Sishuai; Xue, Xuzhang; Eneji, A Egrinya; Zhao, Xingbao; Hu, Yuegao

2011-08-30

Nitrate leaching and the resulting groundwater contamination from intensive cereal production has become a major concern for long-term farmland efficiency and environmental sustainability in northern China. The aim of this study was to evaluate a water-saving super-absorbent polymer (SAP) for minimising NO(3)(-) leaching from soil and optimising corn growth and yield. Thirty-six undisturbed soil lysimeters were installed in a field lysimeter facility in drought-affected northern China to study the growth and yield characteristics of summer corn (Zea mays L.) as well as the amount of NO(3)-leaching losses under different fertiliser (standard, medium or 75% and low, or 50% of conventional fertilisation rate) and SAP (control, 0; level-1, 15 kg ha(-1) and level-2, 30 kg ha(-1)) treatments. Corn yield fell by 19.7% under medium and 37.7% under low fertilisation; the application of SAP increased yield significantly by 44.4% on level-1 and 80.3% on level-2. Similarly, plant height, leaf area, number of grains as well as protein, soluble sugar and starch contents in the grain also increased with SAP treatment. Application of SAP at 30 kg ha(-1) plus half of conventional fertilisation can reduce maximum (64.1%) nitrate leaching losses from soil. Application of SAP at 30 kg ha(-1) plus only half the amount of conventional fertiliser rate (150 kg urea, and 50 kg each of superphosphate and potassium sulfate) would be a more appropriate practice both for minimising nitrate leaching and sustainable corn production under the arid and semiarid conditions of northern China. Copyright © 2011 Society of Chemical Industry.
Initial Response of Pine Seedlings and Weeds to Dried Sewage Sludge in Rehabilitation of an Eroded Forest Site

Treesearch

Charles R. Berry

1977-01-01

Dried sewage sludge was applied at rates of 0, 17, 34, and 69 metric tons/ha on a badly eroded forest site in the Piedmont region of northeast Georgia. Production of weed bio mass varied directly with amount of sludge applied. Heigh growth for both shortleafand loblolly pine seedlings appeared to be greater on plots receiving 17 metric tons of sludge/ha, bu differences...
Chemical state of chromium in sewage sludge ash based phosphorus-fertilisers.

PubMed

Vogel, Christian; Adam, Christian; Kappen, Peter; Schiller, Tara; Lipiec, Ewelina; McNaughton, Don

2014-05-01

Sewage sludge ash (SSA) based P-fertilisers were produced by thermochemical treatment of SSA with Cl-donors at approximately 1000°C. During this thermochemical process heavy metals are separated as heavy metal chlorides via the gas phase. Chromium cannot be separated under normal conditions. The risk of the development of toxic Cr(VI) during the thermochemical process was investigated. X-ray Absorption Spectroscopy measurements showed that SSA and thermochemically treated SSA with CaCl2, MgCl2 and NaCl contain Cr(III) compounds only. In contrast, treating SSA with elevated quantities of Na2CO3, to enhance the plant-availability of the phosphate phases of the fertiliser, developed approximately 10-15% Cr(VI). Furthermore, Raman microspectroscopy showed that using Mg-carbonate reduces the risk of a Cr(VI) development during thermochemical treatment. Additionally, leaching tests showed that only a Cr-water solubility>10% is an indicator for Cr(VI) in SSA based P-fertilisers. Copyright © 2013 Elsevier Ltd. All rights reserved.

Study of the effects of proline, phenylalanine, and urea foliar application to Tempranillo vineyards on grape amino acid content. Comparison with commercial nitrogen fertilisers.

PubMed

Garde-Cerdán, T; López, R; Portu, J; González-Arenzana, L; López-Alfaro, I; Santamaría, P

2014-11-15

The aim of this work was to study the influence of foliar application of different nitrogen sources on grape amino acid content. The nitrogen sources applied to Tempranillo grapevines were proline, phenylalanine, urea, and two commercial nitrogen fertilisers, both without and with amino acids in their formulations. All treatments were applied at veraison and one week later. Proline treatment did not affect the must nitrogen composition. However, phenylalanine and urea foliar application enhanced the plants' synthesis of most of the amino acids, producing similar effects. In addition, the spray of commercial nitrogen fertilisers over leaves also induced a rise in grape amino acid concentrations regardless of the presence or absence of amino acids in their formulation. The most effective treatments were phenylalanine and urea followed by nitrogen fertilisers. This finding is of oenological interest for improved must nitrogen composition, ensuring better fermentation kinetics and most likely enhancing wine quality. Copyright © 2014 Elsevier Ltd. All rights reserved.
Progesterone improves porcine in vitro fertilisation system.

PubMed

Malo, Clara; Gil, Lydia; Cano, Rafael; Martinez, Felisa; Gonzalez, Noelia

2014-03-01

In an effort to improve the quality of in vitro produced porcine embryos, the effect of progestagens - progesterone analogues - on the in vitro developmental competence of porcine oocytes was studied. A total of 1421 in vitro matured oocytes, from 4 replicates, were inseminated with frozen-thawed spermatozoa. Progestagens were added to late maturation and embryo cultures (10 IU/ml). Fertilisation success (pre-maturation, penetration, monospermy and efficiency) and nuclear maturation were evaluated. There were no differences among prematuration rates between groups (P = 0.221). Penetration rates were higher (P < 0.001) in the presence of progestagens (75.0%) as compared to the control (51.7%). However, no differences were observed in monospermy percentages (P = 0.246). The results indicated that supplementation with progestagens increased the efficiency of the in vitro fertilisation system (P < 0.001). An additional beneficial effect was observed in nuclear maturation with progestagens (P = 0.035). In summary, progestagen supplementation is an important factor to improve the in vitro fertilisation procedure.
Reducing dissolved inorganic nitrogen in surface runoff water from sugarcane production systems.

PubMed

Webster, A J; Bartley, R; Armour, J D; Brodie, J E; Thorburn, P J

2012-01-01

Nitrogen (N) lost from farms, especially as the highly bioavailable dissolved inorganic form, may be damaging Australia's Great Barrier Reef (GBR). As sugarcane is the dominant cropping system in GBR catchments, its N management practises are coming under increasing scrutiny. This study measured dissolved inorganic N lost in surface runoff water and sugarcane productivity over 3 years. The experiment compared the conventional fertiliser N application rate to sugarcane (average 180kg N/ha/year) and a rate based on replacing N exported in the previous crop (average 94kg N/ha/year). Dissolved inorganic N losses in surface water were 72%, 48% and 66% lower in the three monitored years in the reduced N fertiliser treatment. There was no significant difference in sugarcane yield between the two fertiliser N treatments, nor any treatment difference in soil mineral N - both of these results are indicators of the sustainability of the lower fertiliser N applications. Copyright © 2012 Elsevier Ltd. All rights reserved.
The potential of nutrient reuse from a source-separated domestic wastewater system in Indonesia--case study: ecological sanitation pilot plant in Surabaya.

PubMed

Malisie, A F; Prihandrijanti, M; Otterpohl, R

2007-01-01

Human excreta (faeces and urine) contribute only a small volume in domestic wastewater but are one of the main causes of water pollution. On the other hand, they contain very valuable nutrients to be reused as anthropogenic fertiliser through proper collection, treatment and hygienisation processes. To know the potential of nutrient recovery and reuse in Indonesia, a pilot scale source separation domestic wastewater system has been built in Surabaya and, so far, has shown promising results. Using urine diverting toilets, up to 86% nitrogen, 21% phosphorus and 69% potassium from urine and 12% of nitrogen, 68% of phosphorus and 20% of potassium from the faecal matter can be recovered. The separated urine was stored for 6 months before usage as fertiliser for hygienic reasons, while the separated faecal matter was composted with worms (vermicomposting). In order to investigate the fertilising effect, a preliminary cultivation experiment has been carried out on young rose plants using different fertilisers for 2 months.
N2O and CO2 emissions following repeated application of organic and mineral N fertiliser from a vegetable crop rotation.

PubMed

De Rosa, Daniele; Rowlings, David W; Biala, Johannes; Scheer, Clemens; Basso, Bruno; Grace, Peter R

2018-05-11

Accounting for nitrogen (N) release from organic amendments (OA) can reduce the use of synthetic N-fertiliser, sustain crop production, and potentially reduce soil borne greenhouse gases (GHG) emissions. However, it is difficult to assess the GHG mitigation potential for OA as a substitute of N-fertiliser over the long term due to only part of the organic N added to soil is being released in the first year after application. High-resolution nitrous oxide (N 2 O) and carbon dioxide (CO 2 ) emissions monitored from a horticultural crop rotation over 2.5 years from conventional urea application rates were compared to treatments receiving an annual application of raw and composted chicken manure combined with conventional and reduced N-fertiliser rates. The repeated application of composted manure did not increase annual N 2 O emissions while the application of raw manure resulted in N 2 O emissions up to 35.2 times higher than the zero N fertiliser treatment and up to 4.7 times higher than conventional N-fertiliser rate due to an increase in C and N availability following the repeated application of raw OA. The main factor driving N 2 O emissions was the incorporation of organic material accompanied by high soil moisture while the application of synthetic N-fertiliser induced only short-term N 2 O emission pulse. The average annual N 2 O emission factor calculated accounting for the total N applied including OA was equal to 0.27 ± 0.17%, 3.7 times lower than the IPCC default value. Accounting for the estimated N release from OA only enabled a more realistic N 2 O emission factor to be defined for organically amended field that was equal to 0.48 ± 0.3%. This study demonstrated that accounting for the N released from repeated application of composted rather than raw manure can be a viable pathway to reduce N 2 O emissions and maintain soil fertility. Copyright © 2017. Published by Elsevier B.V.
Response of different-aged black cherry trees to ambient ozone exposure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fredericksen, T.S.; Joyce, B.J.; Kouterick, K.B.

1994-06-01

Black cherry (Prunus serotina Ehrh.) is a valuable commercial timber species which is also highly sensitive to ozone relative to other eastern deciduous tree species. Studies of ozone effects on forest trees have been restricted mostly to experiments using small seedlings under controlled conditions. Yet, mature trees may differ from seedlings in physiology, morphology, and exposure to air pollutants. An experiment was conducted in 1993 to determine differences in ozone uptake and foliar injury symptoms between open-ground seedlings, forest saplings, and mature forest trees of black cherry in northcentral Pennsylvania. Seedlings grew under the highest ozone concentrations and also hadmore » greater seasonal ozone uptake due to higher rates of stomatal conductance. However, because of their indeterminate growth habit, seedlings had lower cumulative ozone uptake per leaf lifespan than saplings or mature trees, both of which had determinate shoot growth. Although greater initially for seedlings, foliar injury was nearly identical between size classes by the end of the growing season. Leaves in the lower crown of larger trees had lower ozone uptake than leaves in the upper crown, but exhibited more foliar injury symptoms. Lower crown leaves received more effective exposure to ozone because of their thinner leaves and had less available photosynthate for repair or replacement of damaged tissue.« less
Combined effects of lead and acid rain on photosynthesis in soybean seedlings.

PubMed

Hu, Huiqing; Wang, Lihong; Liao, Chenyu; Fan, Caixia; Zhou, Qing; Huang, Xiaohua

2014-10-01

To explore how lead (Pb) and acid rain simultaneously affect plants, the combined effects of Pb and acid rain on the chlorophyll content, chlorophyll fluorescence reaction, Hill reaction rate, and Mg(2+)-ATPase activity in soybean seedlings were investigated. The results indicated that, when soybean seedlings were treated with Pb or acid rain alone, the chlorophyll content, Hill reaction rate, Mg(2+)-ATPase activity, and maximal photochemical efficiency (F(v)/F(m)) were decreased, while the initial fluorescence (F 0) and maximum quantum yield (Y) were increased, compared with those of the control. The combined treatment with Pb and acid rain decreased the chlorophyll content, Hill reaction rate, Mg(2+)-ATPase activity, F(v)/F(m), and Y and increased F 0 in soybean seedlings. Under the combined treatment with Pb and acid rain, the two factors showed additive effects on the chlorophyll content in soybean seedlings and exhibited antagonistic effects on the Hill reaction rate. Under the combined treatment with high-concentration Pb and acid rain, the two factors exhibited synergistic effects on the Mg(2+)-ATPase activity, F 0, F v/F m, as well as Y. In summary, the inhibition of the photosynthetic process is an important physiological basis for the simultaneous actions of Pb and acid rain in soybean seedlings.
Non-lethal effects of an invasive species in the marine environment: the importance of early life-history stages.

PubMed

Rius, Marc; Turon, Xavier; Marshall, Dustin J

2009-04-01

Studies examining the effects of invasive species have focussed traditionally on the direct/lethal effects of the invasive on the native community but there is a growing recognition that invasive species may also have non-lethal effects. In terrestrial systems, non-lethal effects of invasive species can disrupt early life-history phases (such as fertilisation, dispersal and subsequent establishment) of native species, but in the marine environment most studies focus on adult rather than early life-history stages. Here, we examine the potential for an introduced sessile marine invertebrate (Styela plicata) to exert both lethal and non-lethal effects on a native species (Microcosmus squamiger) across multiple early life-history stages. We determined whether sperm from the invasive species interfered with the fertilisation of eggs from the native species and found no effect. However, we did find strong effects of the invasive species on the post-fertilisation performance of the native species. The invasive species inhibited the settlement of native larvae and, in the field, the presence of the invasive species was associated with a ten-fold increase in the post-settlement mortality of the native species, as well as an initial reduction of growth in the native. Our results suggest that larvae of the native species avoid settling near the invasive species due to reduced post-settlement survival in its presence. Overall, we found that invasive species can have complex and pervasive effects (both lethal and non-lethal) across the early life-history stages of the native species, which are likely to result in its displacement and to facilitate further invasion.
Altered chromatin condensation of heat-stressed spermatozoa perturbs the dynamics of DNA methylation reprogramming in the paternal genome after in vitro fertilisation in cattle.

PubMed

Rahman, Mohammad Bozlur; Kamal, Md Mostofa; Rijsselaere, Tom; Vandaele, Leen; Shamsuddin, Mohammed; Van Soom, Ann

2014-10-01

Shortly after penetration of the oocyte, sperm DNA is actively demethylated, which is required for totipotent zygotic development. Aberrant DNA methylation is thought to be associated with altered chromatin condensation of spermatozoa. The objectives of this study were to investigate the dynamics of DNA methylation reprogramming in the paternal pronucleus and subsequent fertilisation potential of heat-stressed bull spermatozoa having altered chromatin condensation. Hence, bovine zygotes (n=1239) were collected at three different time points (12, 18 and 24h post insemination, hpi), and stained with an antibody against 5-methylcytosine. Fluorescence intensities of paternal and maternal pronuclei were measured by ImageJ. DNA methylation patterns in paternal pronuclei derived from heat-stressed spermatozoa did not differ between time points (P>0.05), whereas control zygotes clearly showed demethylation and de novo methylation at 18 and 24hpi, respectively. Moreover, heat-stressed spermatozoa showed a highly reduced (P<0.01) fertilisation rate compared with non-heat-stressed or normal control spermatozoa (53.7% vs 70.2% or 81.5%, respectively). Our data show that the normal pattern of active DNA demethylation followed by de novo methylation in the paternal pronucleus is perturbed when oocytes are fertilised with heat-stressed spermatozoa, which may be responsible for decreased fertilisation potential.
Effect of nitrogen fertilisation on the overall quality of minimally processed globe artichoke heads.

PubMed

Lombardo, Sara; Restuccia, Cristina; Muratore, Giuseppe; Barbagallo, Riccardo N; Licciardello, Fabio; Pandino, Gaetano; Scifò, Giovanna O; Mazzaglia, Agata; Ragonese, Francesca; Mauromicale, Giovanni

2017-01-01

Although nitrogen (N) fertilisation is essential for promoting crop yield, it may also affect the produce quality. Here, the influence of three N fertiliser rates (0 kg ha -1 as a control, 200 kg ha -1 and 400 kg ha -1 referred to as N 0 , N 200 and N 400 , respectively) on the overall quality of minimally processed globe artichoke heads was investigated during refrigerated storage for 12 days. Throughout the storage time, N fertilised samples had higher inulin contents than those unfertilised. In addition, the respiratory quotient of N 200 and N 400 samples was 2-fold and 2.5-fold lower than N 0 ones, whose values were close to the normal range for vegetables. All the samples reported good microbiological standards, although N 200 and N 400 achieved lower mesophilic and psychotropic counts than N 0 throughout the storage time. After 8 and 12 days of refrigerated storage, the N 200 samples showed the highest scores of positive sensory descriptors. A fertiliser level of 200 kg N ha -1 is suitable for obtaining minimally processed globe artichoke heads with good nutritional, sensory and microbiological quality, characterised by low endogenous oxidase activities. Proper packaging systems and procedures are, however, crucial for extending the product shelf-life and, thus, promoting its exportation on a wider scale. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.
Timing for a sustainable fertilisation of Glycine max by using HBED/Fe3+ and EDDHA/Fe3+ chelates.

PubMed

Martín-Fernández, Clara; López-Rayo, Sandra; Hernández-Apaolaza, Lourdes; Lucena, Juan J

2017-07-01

Efficient use of Fe chelates is crucial to avoid environmental risks and reduce economic losses. HBED/Fe 3+ has been recently approved by the European Union for soil fertilisation, but studies delving into the best timing for its application are necessary. In this work, a batch incubation experiment and two biological experiments were developed to determine the optimal physiological stage for a sustainable application of HBED/Fe 3+ in soil fertilisation compared with EDDHA/Fe 3+ fertilisers using 57 Fe. HBED/Fe 3+ demonstrated a high durability in soils and soil materials, maintaining more than 80% of Fe chelated after 70 days, and its application at an early physiological stage resulted in a high Fe accumulation in soybean and soil after 36 days. In contrast, the stability of EDDHA/Fe 3+ decreased because of the retention of its lowest stable isomers. The best timing for chelates application was confirmed in a 52 day experiment. The application of HBED/Fe 3+ at the early stage increased the Fe translocation to fruits; while o,o-EDDHA/Fe 3+ accumulated more Fe in fruits when added at the fructification stage. The high HBED/Fe 3+ stability in calcareous soil requires a differentiate application timing, and its addition at early physiological stages leads into the most efficient fertilisation. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.
RESPONSE OF TALL FESCUE, BUSH BEAN, AND MAIZE TO CHROME TANNERY SLUDGE IN SOILS

EPA Science Inventory

Tannery sludge was compared with commercial nitrogen fertiliser to investigate its potential use as an alternative to commercial fertiliser. Soils containing 38% and 7% organic carbon and with nitrogen contents of 1-3% and 0-2%, respectively, were amended with either commercial N...
Plant Gas Exchange at High Wind Speeds 1

PubMed Central

Caldwell, Martyn M.

1970-01-01

High altitude Rhododendron ferrugineum L. and Pinus cembra L. seedlings were exposed to winds at 15 meters per second for 24-hour periods. Wind-sensitive stomata of Rhododendron seedlings immediately initiated a closing response which resulted in decreased photosynthesis and an even greater reduction in transpiration. Stomatal aperture and transpiration rates of P. cembra were only slightly reduced by high speed winds. However, photosynthesis was substantially reduced because of changes in needle display to available irradiation. PMID:16657501
[Response and adaptation of photosynthesis of cucumber seedlings to high temperature stress].

PubMed

Sun, Sheng Nan; Wang, Qiang; Sun, Chen Chen; Liu, Feng Jiao; Bi, Huan Gai; Ai, Xi Zhen

2017-05-18

Cucumber seedlings (Cucumis sativus Jinyou 35) were used to study the effects of high temperature (HT: 42 ℃/32 ℃) and sub-high temperature (SHT: 35 ℃/25 ℃) on its photosynthesis and growth. The results showed that the growth of cucumber seedlings was dramatically inhibited by the high and sub-high temperature stresses. The photosynthetic rate (P n ) was gradually reduced, while intercellular CO 2 concentration (C i ) was increased as heat stress lasted. Under heat stress, stomatal conductance (g s ), transpiration rate (T r ), photorespiration rate (P r ) and dark respiration rate (D r ) showed a trend from rise to decline in cucumber seedlings, which implied that heat-induced decline of photosynthesis was mainly due to non-stomatal limitation. Maximal photochemical efficiency of PS2 in darkness (F v /F m ), actual photochemical efficiency (χ PS 2 ), photochemical quenching (q P ) and electron transport rate (ETR) were severely hampered, while initial fluorescence (F o ) and non-chemical quenching (NPQ) were increased as a result of high and sub-high temperature stresses. Under extended high temperature stress, the activities of RuBP carboxylase (RuBPCase) and Rubisco activase (RCA) as well as the mRNA abundance of Rubisco and RCA were in the trend of decrease, while they were reduced 3 days following the sub-high temperature treatment. The activities and mRNA expressions of sedoheptulose-1,7-bisphosphatase (SBPase) and fructose 1,6-bisphosphate aldolase (FBA) increased initially, but decreased afterwards under heat stress. Taken together, our data suggested that short-term sub-high temperature did not cause photoinhibition under optimal light conditions, however, high temperature led to severe damage to PS2 reaction center in cucumber seedlings. The photosynthetic enzymes were induced by high temperature stress and the induction was affected by temperature and stress duration.
Gibberellin is required for the formation of tension wood and stem gravitropism in Acacia mangium seedlings

PubMed Central

Nugroho, Widyanto Dwi; Yamagishi, Yusuke; Nakaba, Satoshi; Fukuhara, Shiori; Begum, Shahanara; Marsoem, Sri Nugroho; Ko, Jae-Heung; Jin, Hyun-O; Funada, Ryo

2012-01-01

Background and Aims Angiosperm trees generally form tension wood on the upper sides of leaning stems. The formation of tension wood is an important response to gravitational stimulus. Gibberellin appears to be involved in the differentiation of secondary xylem, but it remains unclear whether gibberellin plays a key role in the formation of tension wood and plant gravitropism. Therefore, a study was designed to investigate the effects of gibberellin and of inhibitors of the synthesis of gibberellin, namely paclobutrazole and uniconazole-P, on the formation of tension wood and negative stem gravitropism in Acacia mangium seedlings. Methods Gibberellic acid (GA3), paclobutrazole and uniconazole-P were applied to seedlings via the soil in which they were growing. Distilled water was applied similarly as a control. Three days after such treatment, seedlings were tilted at an angle of 45° from the vertical, and samples of stems were collected for analysis 2 weeks, 2 months and 6 months after tilting. The effects of treatments on the stem recovery degree (Rº) were analysed as an index of the negative gravitropism of seedlings, together the width of the region of tension wood in the upper part of inclined stems. Key Results It was found that GA3 stimulated the negative gravitropism of tilted seedling stems of A. mangium, while paclobutrazole and uniconazole-P inhibited recovery to vertical growth. Moreover, GA3 stimulated the formation of tension wood in tilted A. mangium seedlings, while paclobutrazole and uniconazole-P strongly suppressed the formation of tension wood, as assessed 2 weeks after tilting. Conclusions The results suggest that gibberellin plays an important role at the initial stages of formation of tension wood and in stem gravitropism in A. mangium seedlings in response to a gravitational stimulus. PMID:22843341
Sensitivity of cold acclimation to elevated autumn temperature in field-grown Pinus strobus seedlings

PubMed Central

Chang, Christine Y.; Unda, Faride; Zubilewich, Alexandra; Mansfield, Shawn D.; Ensminger, Ingo

2015-01-01

Climate change will increase autumn air temperature, while photoperiod decrease will remain unaffected. We assessed the effect of increased autumn air temperature on timing and development of cold acclimation and freezing resistance in Eastern white pine (EWP, Pinus strobus) under field conditions. For this purpose we simulated projected warmer temperatures for southern Ontario in a Temperature Free-Air-Controlled Enhancement (T-FACE) experiment and exposed EWP seedlings to ambient (Control) or elevated temperature (ET, +1.5°C/+3°C during day/night). Photosynthetic gas exchange, chlorophyll fluorescence, photoprotective pigments, leaf non-structural carbohydrates (NSC), and cold hardiness were assessed over two consecutive autumns. Nighttime temperature below 10°C and photoperiod below 12 h initiated downregulation of assimilation in both treatments. When temperature further decreased to 0°C and photoperiod became shorter than 10 h, downregulation of the light reactions and upregulation of photoprotective mechanisms occurred in both treatments. While ET seedlings did not delay the timing of the downregulation of assimilation, stomatal conductance in ET seedlings was decreased by 20–30% between August and early October. In both treatments leaf NSC composition changed considerably during autumn but differences between Control and ET seedlings were not significant. Similarly, development of freezing resistance was induced by exposure to low temperature during autumn, but the timing was not delayed in ET seedlings compared to Control seedlings. Our results indicate that EWP is most sensitive to temperature changes during October and November when downregulation of photosynthesis, enhancement of photoprotection, synthesis of cold-associated NSCs and development of freezing resistance occur. However, we also conclude that the timing of the development of freezing resistance in EWP seedlings is not affected by moderate temperature increases used in our field experiments. PMID:25852717
Gibberellin is required for the formation of tension wood and stem gravitropism in Acacia mangium seedlings.

PubMed

Nugroho, Widyanto Dwi; Yamagishi, Yusuke; Nakaba, Satoshi; Fukuhara, Shiori; Begum, Shahanara; Marsoem, Sri Nugroho; Ko, Jae-Heung; Jin, Hyun-O; Funada, Ryo

2012-09-01

Angiosperm trees generally form tension wood on the upper sides of leaning stems. The formation of tension wood is an important response to gravitational stimulus. Gibberellin appears to be involved in the differentiation of secondary xylem, but it remains unclear whether gibberellin plays a key role in the formation of tension wood and plant gravitropism. Therefore, a study was designed to investigate the effects of gibberellin and of inhibitors of the synthesis of gibberellin, namely paclobutrazole and uniconazole-P, on the formation of tension wood and negative stem gravitropism in Acacia mangium seedlings. Gibberellic acid (GA(3)), paclobutrazole and uniconazole-P were applied to seedlings via the soil in which they were growing. Distilled water was applied similarly as a control. Three days after such treatment, seedlings were tilted at an angle of 45° from the vertical, and samples of stems were collected for analysis 2 weeks, 2 months and 6 months after tilting. The effects of treatments on the stem recovery degree (Rº) were analysed as an index of the negative gravitropism of seedlings, together the width of the region of tension wood in the upper part of inclined stems. It was found that GA(3) stimulated the negative gravitropism of tilted seedling stems of A. mangium, while paclobutrazole and uniconazole-P inhibited recovery to vertical growth. Moreover, GA(3) stimulated the formation of tension wood in tilted A. mangium seedlings, while paclobutrazole and uniconazole-P strongly suppressed the formation of tension wood, as assessed 2 weeks after tilting. The results suggest that gibberellin plays an important role at the initial stages of formation of tension wood and in stem gravitropism in A. mangium seedlings in response to a gravitational stimulus.
Colonization of citrus seed coats by 'Candidatus Liberibacter asiaticus': implications for seed transmission of the bacterium.

PubMed

Hilf, Mark E

2011-10-01

Huanglongbing is an economically damaging disease of citrus associated with infection by 'Candidatus Liberibacter asiaticus'. Transmission of the organism via infection of seeds has not been demonstrated but is a concern since some citrus varieties, particularly those used as rootstocks in commercial plantings are propagated from seed. We compared the incidence of detection of 'Ca. Liberibacter asiaticus' DNA in individual fruit peduncles, seed coats, seeds, and in germinated seedlings from 'Sanguenelli' sweet orange and 'Conners' grapefruit fruits sampled from infected trees. Using real-time quantitative PCR (qPCR) we detected pathogen DNA in nucleic acid extracts of 36 and 100% of peduncles from 'Sanguenelli' and from 'Conners' fruits, respectively. We also detected pathogen DNA in extracts of 37 and 98% of seed coats and in 1.6 and 4% of extracts from the corresponding seeds of 'Sanguenelli' and 'Conners', respectively. Small amounts of pathogen DNA were detected in 10% of 'Sanguenelli' seedlings grown in the greenhouse, but in none of 204 extracts from 'Conners' seedlings. Pathogen DNA was detected in 4.9% and in 89% of seed coats peeled from seeds of 'Sanguenelli' and 'Conners' which were germinated on agar, and in 5% of 'Sanguenelli' but in none of 164 'Conners' seedlings which grew from these seeds on agar. No pathogen DNA was detected in 'Ridge Pineapple' tissue at 3 months post-grafting onto 'Sanguenelli' seedlings, even when pathogen DNA had been detected initially in the 'Sanguenelli' seedling. Though the apparent colonization of 'Conners' seeds was more extensive and nearly uniform compared with 'Sanguenelli' seeds, no pathogen DNA was detected in 'Conners' seedlings grown from these seeds. For either variety, no association was established between the presence of pathogen DNA in fruit peduncles and seed coats and in seedlings.
Dying piece by piece: carbohydrate dynamics in aspen (Populus tremuloides) seedlings under severe carbon stress.

PubMed

Wiley, Erin; Hoch, Günter; Landhäusser, Simon M

2017-11-02

Carbon starvation as a mechanism of tree mortality is poorly understood. We exposed seedlings of aspen (Populus tremuloides) to complete darkness at 20 or 28 °C to identify minimum non-structural carbohydrate (NSC) concentrations at which trees die and to see if these levels vary between organs or with environmental conditions. We also first grew seedlings under different shade levels to determine if size affects survival time under darkness due to changes in initial NSC concentration and pool size and/or respiration rates. Darkness treatments caused a gradual dieback of tissues. Even after half the stem had died, substantial starch reserves were still present in the roots (1.3-3% dry weight), indicating limitations to carbohydrate remobilization and/or transport during starvation in the absence of water stress. Survival time decreased with increased temperature and with increasing initial shade level, which was associated with smaller biomass, higher respiration rates, and initially smaller NSC pool size. Dead tissues generally contained no starch, but sugar concentrations were substantially above zero and differed between organs (~2% in stems up to ~7.5% in leaves) and, at times, between temperature treatments and initial, pre-darkness shade treatments. Minimum root NSC concentrations were difficult to determine because dead roots quickly began to decompose, but we identify 5-6% sugar as a potential threshold for living roots. This variability may complicate efforts to identify critical NSC thresholds below which trees starve. © Society for Experimental Biology 2017.
Growth models of Rhizophora mangle L. seedlings in tropical southwestern Atlantic

NASA Astrophysics Data System (ADS)

Lima, Karen Otoni de Oliveira; Tognella, Mônica Maria Pereira; Cunha, Simone Rabelo; Andrade, Humber Agrelli de

2018-07-01

The present study selected and compared regression models that best describe the growth curves of Rhizophora mangle seedlings based on the height (cm) and time (days) variables. The Linear, Exponential, Power Law, Monomolecular, Logistic, and Gompertz models were adjusted with non-linear formulations and minimization of the sum of the squares of the residues. The Akaike Information Criterion was used to select the best model for each seedling. After this selection, the determination coefficient, which evaluates how well a model describes height variation as a time function, was inspected. Differing from the classic population ecology studies, the Monomolecular, Three-parameter Logistic, and Gompertz models presented the best performance in describing growth, suggesting they are the most adequate options for long-term studies. The different growth curves reflect the complexity of stem growth at the seedling stage for R. mangle. The analysis of the joint distribution of the parameters initial height, growth rate, and, asymptotic size allowed the study of the species ecological attributes and to observe its intraspecific variability in each model. Our results provide a basis for interpretation of the dynamics of seedlings growth during their establishment in a mature forest, as well as its regeneration processes.

Effects of Salinity and Nutrient Addition on Mangrove Excoecaria agallocha

PubMed Central

Chen, Yaping; Ye, Yong

2014-01-01

Effects of salinity on seed germination and growth of young (1 month old) and old (2-year old) seedlings of Excoecaria agallocha were investigated. Combined effects of salinity and nutrient level were also examined on old seedlings. Seed germination was best at 0 and 5 psu salinity. 15 psu salinity significantly delayed root initiation and decreased final establishment rate. All seeds failed to establish at 25 psu salinity. Young seedlings performed best at 0 and 5 psu, but growth was stunned at 15 psu, and all seedlings died within 90 days at 25 psu. Old seedlings grew best at salinities below 5 psu and they survived the whole cultivation at 25 psu. This indicated that E. agallocha increased salt tolerance over time. Gas exchange was significantly compromised by salinities above 15 psu but evidently promoted by high nutrient. Proline accumulated considerably at high nutrient, and its contents increased from 0 to 15 psu but decreased at 25 psu salinity. Lipid peroxidation was aggravated by increasing salinity beyond 15 psu but markedly alleviated by nutrient addition. These responses indicated that E. agallocha was intolerant to high salinity but it can be greatly enhanced by nutrient addition. PMID:24691495
Screening of bacterial antagonists for biological control of Phytophthora blight of pepper.

PubMed

Rajkumar, M; Lee, Wang Hyu; Lee, Kui Jae

2005-01-01

The aim of this study was to assess the potential of bacterial antagonists to control Phytophthora blight of pepper caused by P. capsici using different screening methods. Among a collection of fluorescent pseudomonas isolated from the rhizosphere of pepper, twelve isolates were initially selected based on dual culture assay on potato dextrose agar and corn meal agar. Further, these twelve isolates were screened for the reduction of disease severity caused by P. capsici using detached leaves and seedling assay. Most of the antagonists showed varying levels of antagonism against P. capsici in both detached leaves and seedlings assay. In addition, few isolates increased shoot and root length of pepper in seedling assays. Among them, isolate PS119 showing highest ability to reduce the disease severity in the in vitro seedling assay was found to be the most efficient antagonists against P. capsici in the in vivo biological control tests. These results indicate that the in vitro seedling assay can be used as a rapid and more accurate technique for the selection of promising biocontrol agents against P. capsici. ((c) 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim).
Interactive effects of cadmium and acid rain on photosynthetic light reaction in soybean seedlings.

PubMed

Sun, Zhaoguo; Wang, Lihong; Chen, Minmin; Wang, Lei; Liang, Chanjuan; Zhou, Qing; Huang, Xiaohua

2012-05-01

Interactive effects of cadmium (Cd(2+)) and acid rain on photosynthetic light reaction in soybean seedlings were investigated under hydroponic conditions. Single treatment with Cd(2+) or acid rain and the combined treatment decreased the content of chlorophyll, Hill reaction rate, the activity of Mg(2+)-ATPase, maximal photochemical efficiency and maximal quantum yield, increased initial fluorescence and damaged the chloroplast structure in soybean seedlings. In the combined treatment, the change in the photosynthetic parameters and the damage of chloroplast structure were stronger than those of any single pollution. Meanwhile, Cd(2+) and acid rain had the interactive effects on the test indices in soybean seedlings. The results indicated that the combined pollution of Cd(2+) and acid rain aggravated the toxic effect of the single pollution of Cd(2+) or acid rain on the photosynthetic parameters due to the serious damage to the chloroplast structure. Copyright © 2011 Elsevier Inc. All rights reserved.
Egg fertilisation in a freshwater mussel: effects of distance, flow and male density

Treesearch

Tyler L. Mosley; Wendell R. Haag; James A. Stoeckel

2014-01-01

1. Small or sparse populations can experience Allee effects if egg fertilisation is reduced because of a shortage of sperm. 2. Freshwater mussels are spermcasters that often occur as sparse, patchy populations. Previous studies suggested that sperm shortage limits these populations unless facultative hermaphroditism and selffertilisation occur at low density...
Influence of mitochondrial membrane potential of spermatozoa on in vitro fertilisation outcome.

PubMed

Marchetti, P; Ballot, C; Jouy, N; Thomas, P; Marchetti, C

2012-04-01

To determine whether the outcome of in vitro fertilisation (IVF) is influenced by the percentage of spermatozoa with functional mitochondria, a total of 91 random couples undergoing IVF were included. Mitochondrial function was determined by flow cytometry and expressed as percentage of spermatozoa. Conventional sperm parameters were studied by light microscopy. Reproductive outcome parameters were fertilisation rate, embryo quality and clinical pregnancy. It was found that the fertilisation rate was correlated with the percentage of spermatozoa (r = 0.24, P = 0.01) as well as with the percentage of highly motile spermatozoa. However, we did not find any relationship between the percentage of spermatozoa and embryo quality. Nevertheless, no patient who exhibited less than 64% of spermatozoa achieved pregnancy. It is concluded that determination of Δψ(m) provides accurate information to guide physicians to identify male patients for whom IVF will be unlikely to result in pregnancy. Therefore, we suggest that the percentage of spermatozoa may contribute to identify the most appropriate treatment for an individual patient. © 2011 Blackwell Verlag GmbH.
Assessment of sperm hyperactivated motility and acrosome reaction can discriminate the use of spermatozoa for conventional in vitro fertilisation or intracytoplasmic sperm injection: preliminary results.

PubMed

Wiser, A; Sachar, S; Ghetler, Y; Shulman, A; Breitbart, H

2014-04-01

Basic semen analysis is insufficient for determining the fertility potential. The aim of this study was to determine if hyperactivated motility (HAM) and acrosome reaction (AR) can be useful tests for evaluating semen quality during male infertility evaluations and to help the clinician decide whether regular insemination or intracytoplasmic sperm injection (ICSI) is preferable during in vitro fertilisation. A prospective study was conducted. Patients with normal sperm according to World Health Organization guidelines who underwent IVF treatment and planned regular insemination were asked to participate. A portion of sperm sample was evaluated for HAM and AR on day of ovum pick up. In HAM assessment, 93.3% of patients with increased HAM had a high fertilisation rate compared with 64% in the group without increased HAM (P = 0.059). For the AR evaluation, 91.7% of samples with a low rate of spontaneous AR had a high fertilisation rate compared with 39.3% in the group with a high rate of spontaneous AR (P = 0.004). © 2013 Blackwell Verlag GmbH.
Nitrogen use efficiency in grain production and the estimated nitrogen input/output balance in China agriculture.

PubMed

Li, Shutian; He, Ping; Jin, Jiyun

2013-03-30

Understanding the nitrogen (N) use efficiency and N input/output balance in the agricultural system is crucial for best management of N fertilisers in China. In the last 60 years, N fertiliser consumption correlated positively with grain production. During that period the partial factor productivity of N (PFPN ) declined greatly from more than 1000 kg grain kg⁻¹ N in the 1950s to nearly 30 kg grain kg⁻¹ N in 2008. This change in PFPN could be largely explained by the increase in N rate. The average agronomic efficiency of fertiliser N (AEN ) for rice, wheat and maize during 2000-2010 was 12.6, 8.3 and 11.5 kg kg⁻¹ respectively, which was similar to that in the early 1980s but lower than that in the early 1960s. Estimation based on statistical data showed that a total of 49.16 × 10⁶ t of N was input into Chinese agriculture, of which chemical N, organic fertiliser N, biological fixed N and other sources accounted for 58.2, 24.3, 10.5 and 7.0% respectively. Nitrogen was surplus in all regions, the total N surplus being 10.6 × 10⁶ t (60.6 kg ha⁻¹). The great challenge is to balance the use of current N fertilisers between regions and crops to improve N use efficiency while maintaining or increasing crop production under the high-intensity agricultural system of China. © 2012 Society of Chemical Industry.
Sperm characteristics and heterologous in vitro fertilisation capacity of Iberian ibex (Capra pyrenaica) epididymal sperm, frozen in the presence of the enzymatic antioxidant catalase.

PubMed

López-Saucedo, J; Paramio, M T; Fierro, R; Izquierdo, D; Catalá, M G; Coloma, M A; Toledano-Díaz, A; López-Sebastián, A; Santiago-Moreno, J

2014-06-01

The aim of this work was to evaluate the protective effect of catalase (CAT) on frozen/thawed ibex epididymal sperm recovered post mortem, and to detect any harmful effect this might have on sperm fertilisation capacity. Epididymal spermatozoa were diluted using a Tris-citric acid-glucose medium (TCG) composed of 3.8% Tris (w/v), 2.2% citric acid (w/v), 0.6% glucose (w/v), 5% glycerol (v/v), and 6% egg yolk (v/v). Sperm masses from the right epididymis were diluted with TCG medium, while those from the left were diluted with TCG medium supplemented with 200IU/mL CAT. Heterologous in vitro fertilisation (IVF) was used to assess the fertilisation capacity of this sperm. The addition of CAT to the extender did not improve frozen/thawed sperm variables. Moreover, a reduced fertilisation capacity was detected: sperm diluted with TCG provided 25.5% 2PN zygotes, while just 13.2% was recorded for that diluted with TCG-CAT (P<0.01). The percentage of cleaved embryos at 48hpi was higher (P<0.01) with the TCG sperm than with the TCG-CAT sperm (16.7% vs. 7.6%). The use of 200IU/mL CAT as an additive cannot, therefore, be recommended for the preservation of ibex epididymal sperm. Other antioxidants should, however, be tested in both this and related wild mountain ungulates. Copyright © 2014 Elsevier Inc. All rights reserved.
Zona pellucida from fertilised human oocytes induces a voltage-dependent calcium influx and the acrosome reaction in spermatozoa, but cannot be penetrated by sperm

PubMed Central

Patrat, Catherine; Auer, Jana; Fauque, Patricia; Leandri, Roger L; Jouannet, Pierre; Serres, Catherine

2006-01-01

Background The functions of three zona glycoproteins, ZP1, ZP2 and ZP3 during the sperm-zona pellucida (ZP) interaction are now well established in mice. The expression of an additional zona glycoprotein, ZPB/4, in humans, led us to reconsider the classical mouse model of gamete interaction. We investigated the various functions of human ZP (hZP) during the interaction of spermatozoa with fertilised and unfertilised oocytes. Results The hZP of fertilised oocytes retained their ability to bind sperm (albeit less strongly than that from unfertilised oocytes), to induce an intraspermatic calcium influx through voltage-dependent channels similar to that observed with hZP from unfertilised oocytes and to promote the acrosome reaction at a rate similar to that induced by the ZP of unfertilised oocytes (61.6 ± 6.2% vs60.7 ± 9.1% respectively). Conversely, the rate of hZP penetrated by sperm was much lower for fertilised than for unfertilised oocytes (19% vs 57% respectively, p < 0.01). We investigated the status of ZP2 in the oocytes used in the functional tests, and demonstrated that sperm binding and acrosome reaction induction, but not ZP penetration, occurred whether or not ZP2 was cleaved. Conclusion The change in ZP function induced by fertilisation could be different in human and mouse species. Our results suggest a zona blocking to polyspermy based at the sperm penetration level in humans. PMID:17147816
Dimorphic sperm and the unlikely route to fertilisation in the yellow seahorse.

PubMed

Van Look, Katrien J W; Dzyuba, Borys; Cliffe, Alex; Koldewey, Heather J; Holt, William V

2007-02-01

Uniquely among vertebrates, seahorses and pipefishes (Family Syngnathidae) incubate their eggs within a male brood pouch. This has contributed to a widespread, but poorly founded belief, that the eggs are fertilised using spermatozoa that are deposited directly into the brood pouch via an internal sperm duct. Anatomical dissections showed, however, not only that direct sperm deposition into the pouch is physically impossible, but that spermatozoa must somehow travel a significant distance (>4 mm) outside the body of the male, to reach and fertilise eggs in the pouch. Observations of courtship and mating behaviour also revealed that the pouch closes immediately after mating, and that sperm transfer must occur within a time window of no more than 6 s. In addition to this, the yellow seahorse produces extraordinarily low quantities of dimorphic spermatozoa, but is nevertheless highly fertile and can produce broods that exceed 100 embryos. The entire fertilisation process in seahorses is therefore uniquely efficient among vertebrates, yet paradoxically involves several steps that would seem to complicate, and even appear to prevent, the interaction of the gametes. Although we are still unable to describe the exact fertilisation mechanism, we speculate that spermatozoa are ejaculated into a mixture of ovarian fluid and eggs, while the male and female are in close contact. Thereafter, this mixture must enter the pouch, whereupon the spermatozoa encounter seawater. These observations also support the view, indirectly inferred in previous publications, that sperm competition in seahorses is not only non-existent but impossible.
Fate and survival of Salmonella Typhimurium and Escherichia coli O157:H7 in repacked soil lysimeters after application of cattle slurry and human urine.

PubMed

Nyberg, Karin A; Ottoson, Jakob R; Vinnerås, Björn; Albihn, Ann

2014-09-01

Use of cattle slurry as a fertiliser is common practice around the world. Human urine use is not as common, but owing to its fertiliser value this might change in the future. It is essential to minimise the transfer of enteric pathogens through fertilisation, with respect to both animal and public health. Therefore the objective of this research was to study the survival and transport of Salmonella Typhimurium and Escherichia coli O157:H7 in two agricultural soils when applied to soil along with either cattle slurry or human urine over a period of 180 days. Both Salmonella and E. coli O157:H7 were more rapidly reduced when applied together with human urine than when applied with cattle slurry. However, both pathogens persisted in low amounts at 20 and 50 cm depth in both soils throughout the whole study period. No Salmonella or E. coli O157:H7 was detected in the leachate over the 180 day study. The risk of disease transmission is higher when cattle slurry is used as fertiliser compared with human urine. However, the risk of groundwater infiltration would be low as long as water velocity through the soil is moderate. Increased knowledge of pathogen persistence in soil after fertiliser application is a valuable tool for improving risk evaluations and formulating guidelines for the use of cattle and/or human wastes in cropping soils. © 2014 Society of Chemical Industry.
Nitrogen oxides and ozone fluxes from an oilseed-rape management cycle: the influence of cattle slurry application

NASA Astrophysics Data System (ADS)

Vuolo, Raffaella M.; Loubet, Benjamin; Mascher, Nicolas; Gueudet, Jean-Christophe; Durand, Brigitte; Laville, Patricia; Zurfluh, Olivier; Ciuraru, Raluca; Stella, Patrick; Trebs, Ivonne

2017-05-01

This study reports NO, NO2 and O3 mixing ratios and flux measurements using the eddy covariance method during a 7-month period over an oilseed-rape field, spanning an organic and a mineral fertilisation event. Cumulated NO emissions during the whole period were in agreement with previous studies and showed quite low emissions of 0.26 kg N ha-1 with an emission factor of 0.27 %, estimated as the ratio between total N emitted in the form of NO and total N input. The NO emissions were higher following organic fertilisation in August due to conditions favouring nitrification (soil water content around 20 % and high temperatures), while mineral fertilisation in February did not result in high emissions. The ozone deposition velocity increased significantly after organic fertilisation. The analysis of the chemical and turbulent transport times showed that reactions between NO, NO2 and O3 below the measurement height occurred constantly throughout the 7-month period. Following organic fertilisation, the NO ground fluxes were 30 % larger than the NO fluxes at the measurement height (3.2 m), while the NO2 fluxes switched from deposition to emission during certain periods, being negative at the surface and positive at the measurement height. This phenomenon of apparent NO2 emissions appears to be significant during strong NO emissions and high O3 ambient mixing ratios, even on a bare soil during August.
Embryo developmental capacity of oocytes fertilised by sperm of mouse exposed to forced swimming stress.

PubMed

Ghasem, Saki; Majid, Jasemi; Shiva, Razi

2013-07-01

To assess developmental capacity of fertilised oocytes by sperm of mouse exposed to forced swimming stress. The experimental study was conducted at the Physiology Research Center of Ahvaz Jundishapur University of Medical Sciences, from August 2011 to January 2012. It comprised 20 adult male and 10 female mice. The male mice were randomly divided into two equal groups (n=10): control and experimental. Animals of the experimental group were submitted to forced swimming stress. All male mice were euthanised and the cauda epididymis removed before contents were squeezed out. A pre-incubated capacitated sperm was gently added to the freshly collected ova of the two groups of study. The combined sperm-oocyte suspension was incubated for 4-6 hours under a condition of 5% Carbon dioxide and 37 degreeC temperature. The ova were then washed through several changes of medium and finally incubated. Fertilisation was assessed by recording the number of 1-cell embryos 4-6 hours after insemination. The 1-cell embryos were allowed to further develop in vitro for about 120 hours. Development of embryos everyday and during 5 days of culture was observed by using inverted microscope. SPSS 13.0.1 was used for statistical analysis. The percentage of oocytes fertilised was 75:96 (78.12+/-4.8%) and 50:10 (49.5+/-3.9%) in the control and experimental groups, respectively. The difference was significant (p <0.001). At 24 hours after insemination, 70:75 (93.33+/-2.7%) and 39:50 (78+/-3.5%)of fertilized oocytes developed to two=cell embryos in control and experimental groups respectively.The difference was significant (p <0.02).There were not significant differences (p>0.05) between the two groups in terms of speed and developmental capacity of blastocysts. Fertilisation capacity of male mice affected by forced swimming stress and also the developmental capacity of oocyte fertilised by sperm of mouse exposed to forced swimming stress decreased.
Gene Expression Changes in Phosphorus Deficient Potato (Solanum tuberosum L.) Leaves and the Potential for Diagnostic Gene Expression Markers

PubMed Central

Hammond, John P.; Broadley, Martin R.; Bowen, Helen C.; Spracklen, William P.; Hayden, Rory M.; White, Philip J.

2011-01-01

Background There are compelling economic and environmental reasons to reduce our reliance on inorganic phosphate (Pi) fertilisers. Better management of Pi fertiliser applications is one option to improve the efficiency of Pi fertiliser use, whilst maintaining crop yields. Application rates of Pi fertilisers are traditionally determined from analyses of soil or plant tissues. Alternatively, diagnostic genes with altered expression under Pi limiting conditions that suggest a physiological requirement for Pi fertilisation, could be used to manage Pifertiliser applications, and might be more precise than indirect measurements of soil or tissue samples. Results We grew potato (Solanum tuberosum L.) plants hydroponically, under glasshouse conditions, to control their nutrient status accurately. Samples of total leaf RNA taken periodically after Pi was removed from the nutrient solution were labelled and hybridised to potato oligonucleotide arrays. A total of 1,659 genes were significantly differentially expressed following Pi withdrawal. These included genes that encode proteins involved in lipid, protein, and carbohydrate metabolism, characteristic of Pi deficient leaves and included potential novel roles for genes encoding patatin like proteins in potatoes. The array data were analysed using a support vector machine algorithm to identify groups of genes that could predict the Pi status of the crop. These groups of diagnostic genes were tested using field grown potatoes that had either been fertilised or unfertilised. A group of 200 genes could correctly predict the Pi status of field grown potatoes. Conclusions This paper provides a proof-of-concept demonstration for using microarrays and class prediction tools to predict the Pi status of a field grown potato crop. There is potential to develop this technology for other biotic and abiotic stresses in field grown crops. Ultimately, a better understanding of crop stresses may improve our management of the crop, improving the sustainability of agriculture. PMID:21935429
Reducing nitrous oxide emissions by changing N fertiliser use from calcium ammonium nitrate (CAN) to urea based formulations.

PubMed

Harty, M A; Forrestal, P J; Watson, C J; McGeough, K L; Carolan, R; Elliot, C; Krol, D; Laughlin, R J; Richards, K G; Lanigan, G J

2016-09-01

The accelerating use of synthetic nitrogen (N) fertilisers, to meet the world's growing food demand, is the primary driver for increased atmospheric concentrations of nitrous oxide (N2O). The IPCC default emission factor (EF) for N2O from soils is 1% of the N applied, irrespective of its form. However, N2O emissions tend to be higher from nitrate-containing fertilisers e.g. calcium ammonium nitrate (CAN) compared to urea, particularly in regions, which have mild, wet climates and high organic matter soils. Urea can be an inefficient N source due to NH3 volatilisation, but nitrogen stabilisers (urease and nitrification inhibitors) can improve its efficacy. This study evaluated the impact of switching fertiliser formulation from calcium ammonium nitrate (CAN) to urea-based products, as a potential mitigation strategy to reduce N2O emissions at six temperate grassland sites on the island of Ireland. The surface applied formulations included CAN, urea and urea with the urease inhibitor N-(n-butyl) thiophosphoric triamide (NBPT) and/or the nitrification inhibitor dicyandiamide (DCD). Results showed that N2O emissions were significantly affected by fertiliser formulation, soil type and climatic conditions. The direct N2O emission factor (EF) from CAN averaged 1.49% overall sites, but was highly variable, ranging from 0.58% to 3.81. Amending urea with NBPT, to reduce ammonia volatilisation, resulted in an average EF of 0.40% (ranging from 0.21 to 0.69%)-compared to an average EF of 0.25% for urea (ranging from 0.1 to 0.49%), with both fertilisers significantly lower and less variable than CAN. Cumulative N2O emissions from urea amended with both NBPT and DCD were not significantly different from background levels. Switching from CAN to stabilised urea formulations was found to be an effective strategy to reduce N2O emissions, particularly in wet, temperate grassland. Copyright © 2016 Elsevier B.V. All rights reserved.
Sewage sludge stabilisation and fertiliser value in a silvopastoral system developed with Eucalyptus nitens Maiden in Lugo (Spain).

PubMed

Mosquera-Losada, M R; Ferreiro-Domínguez, N; Daboussi, S; Rigueiro-Rodríguez, A

2016-10-01

Copper (Cu) is one of the heavy metals with highest proportion in sewage sludge. In Europe, sewage sludge should be stabilised before using it as a fertiliser in agriculture. Depending on the stabilisation process, sewage sludge has different Cu contents, and soil Cu incorporation rates. This study was undertaken to examine the effect of fertilisation with different types of sewage sludge (anaerobic, composted, and pelletised) on the concentration of total and available Cu in the soil, the tree growth, the pasture production, and the concentration of Cu in the pasture when compared with control treatments (i.e. no fertilisation and mineral fertilisation) in a silvopastoral system under Eucalyptus nitens Maiden. The results of this experiment show that an improvement of the soil pH increased the incorporation and the mineralisation of the sewage sludge and litter, and therefore, the release of Cu from the soil. Moreover, the concentration of Cu in the pasture and the levels of Cu extracted by the pasture improved when the soil organic matter decreased because the high levels of organic matter in the soil could have formed Cu complex. The composted sewage sludge (COM) increased a) the soil variables studied (pH, total Cu, and available Cu) and b) the Cu extracted by the pasture, both probably due to the higher inputs of cations made with it. In any case, the levels of Cu found in the soil never exceeded the maximums as set by Spanish regulations and did not cause harmful effects on the plants and animals. Therefore, the use of COM as an organic fertiliser should be promoted in silvopastoral systems established in edaphoclimatic conditions similar to this study because COM enhanced the productivity of the system from a viewpoint of the soil and the pasture, without causing any environmental damage. Copyright © 2016 Elsevier B.V. All rights reserved.
Early seedling vigour, an imperative trait for direct-seeded rice: an overview on physio-morphological parameters and molecular markers.

PubMed

Mahender, A; Anandan, A; Pradhan, S K

2015-05-01

Rapid uniform germination and accumulation of biomass during initial phase of seedling establishment is an essential phenotypic trait considered as early seedling vigour for direct seeded situation in rice irrespective of environment. Enhanced role of carbohydrate, amylase, growth hormones, antioxidant enzymes and ascorbic acid brings changes in vigour and phenotype of seedling. Early establishment and demanding life form dominate the surroundings. Crop plant that has better growth overdrives the weed plant and suppresses its growth. Seedling early vigour is the characteristic of seed quality and describes the rapid, uniform germination and the establishment of strong seedlings in any environmental condition. The phenotype of modern rice varieties has been changed into adaptable for transplanted rice with thirst toward water and selection pressure for semi-dwarf architecture resulting in reduced early vigour. Decreasing freshwater availability and rising labour cost drives the search for a suitable alternative management system to enhance grain yield productivity for the burgeoning world population. In view of these issues, much attention has been focused on dry direct-seeded rice, because it demands low input. A rice cultivar with a strong seedling vigour trait is desirable in case of direct seeding. However, seedling vigour has not been selected in crop improvement programmes in conventional breeding due to its complex nature and quantitative inheritance. Molecular markers have been proven effective in increasing selection efficiency, particularly for quantitative traits that are simply inherited. Marker-assisted selection approach has facilitated efficient and precise transfer of genes/QTL(s) into many crop species and suggests a speedy and efficient technique over conventional breeding and selection methods. In this review, we present the findings and investigations in the field of seedling vigour in rice that includes the nature of inheritance of physio-morphological and biochemical traits and QTLs to assist plant breeders who work for direct-seeded rice.
Avicennia schaueriana (Acanthaceae) from Southern Brazil.

PubMed

Pelozo, Andressa; Boeger, Maria Regina T; Sereneski-de-Lima, Carolina; Soffiatti, Patricia

2016-03-01

The initial phase of a plant life cycle is a short and critical period, when individuals are more vulnerable to environmental factors. The morphological and anatomical study of seedlings and saplings leaf type enables the understanding of species strategies of fundamental importance in their establishment and survival. The objective of this study was to analyze the structure of seedlings and saplings leaf types of three mangrove species, Avicennia schaueriana, Laguncularia racemosa, Rhizophora mangle, to understand their early life adaptive strategies to the environment. A total of 30 fully expanded cotyledons (A. schaueriana and L. racemosa), 30 leaves of seedlings, and 30 leaves of saplings of each species were collected from a mangrove area in Guaratuba Bay, Paraná State, Brazil. Following standard methods, samples were prepared for morphological (leaf dry mass, density, thickness) and anatomical analysis (epidermis and sub-epidermal layers, stomata types, density of salt secretion glands, palisade and spongy parenchyma thickness). To compare leaf types among species one-way ANOVA and Principal Component Analysis were used, while Cluster Analysis evaluated differences between the species. We observed significant structural differences among species leaf types. A. schaueriana showed the thickest cotyledons, while L. racemosa presented a dorsiventral structure. Higher values of the specific leaf area were observed for seedlings leaves of A. schaueriana, cotyledons of L. racemosa and saplings leaves of A. schaueriana and R. mangle. Leaf density was similar to cotyledons and seedlings leaves in A. schaueriana and L. racemosa, while R. mangle had seedlings leaves denser than saplings. A. schaueriana and R. mangle showed hypostomatic leaves, while L. racemosa amphistomatic; besides, A. chaueriana showed diacytic stomata, while L. racemosa anomocytic, and R. mangle ciclocytic. Seedling leaves were thicker in R. mangle (535 μm) and L. racemosa (520 μm) than in A. schaueriana (470.3 μm); while saplings leaves were thicker in L. racemosa (568.3 μm) than in A. schaueriana seedlings (512.4 μm) and R. mangle (514.6 μm). Besides, seedlings leaves palisade parenchyma showed increasing thickness in L. racemosa (119.2 μm) < A. schaueriana (155.5 μm) < R. mangle (175.4 μm); while in saplings leaves as follows R. mangle (128.4 μm) < A. schaueriana (183.4 μm) < L. racemosa (193.9 μm). Similarly, seedlings leaves spongy parenchyma thickness values were as follows A. schaueriana (182.6 μm) = R. mangle (192.8 μm) < L. racemosa (354.4 μm); while in saplings were A. schaueriana (182.6 μm) = R. mangle (187.3 μm) < L. racemosa (331.3 μm). The analyzed traits, in different combinations, represent morphological adjustments of leaf types to reduce water loss, eliminate salt excess, increase the absorption of light, allowing a higher efficiency on the maintenance of physiological processes in this initial growth stage.
Digestate and ash as alternatives to conventional fertilisers: Benefits and threats to soil biota

NASA Astrophysics Data System (ADS)

Marshall, Rachel; Lag-Brotons, Alfonso J.; Herbert, Ben; Hurst, Lois; Ostle, Nick; Dodd, Ian C.; Quinton, John; Surridge, Ben; Aiouache, Farid; Semple, Kirk T.

2017-04-01

Recovering energy and nutrients from waste offers opportunities to tackle issues of energy and food security whilst simultaneously improving waste management. Waste materials from the bioenergy industry potentially contain valuable resources for use in agriculture and there is growing evidence to suggest that the use of digestate, from anaerobic digestion, and biomass ash from incineration processes could contribute to improving soil health and nutrition. The work presented here is part of the Adding Value to Ash and Digestate (AVAnD) project which looks at the impacts of digestate and ash blends on soil fertility, crop yields and soil health. Whilst increased crop productivity is one of the essential indicators of the success of these alternative soil amendments; it is important that the impacts on soil biological function is understood. Field and lab experiments were conducted with a number of different fertiliser treatments, including conventional fertiliser (urea and superphosphate), digestate from two contrasting feedstocks, ash material and ash-digestate blends. Looking across different biological scales from soil microbe to soil macro-fauna, this work examines the benefits and threats to soil biota arising from the use of ash-digestate fertilisers in agriculture. Measurements of microbial respiration and biomass (by chloroform fumigation) and community composition (by phospholipid fatty acid analysis) were made at different timescales (days/weeks). Data from these studies demonstrates that none of the soil amendments decreased microbial activity or biomass in the short term (t= 1 month). Additions of both conventional fertilisers and the fertilisers derived from waste stimulated microbial activity with significantly higher respiration observed from the digestate based treatments. Digestate-based treatments also resulted in higher soil microbial biomass and differential effects were observed between digestate amendments with and without ash. These results will be discussed in the context of microbial community change in response to the amendments. At the macro-fauna scale, effects of amendments on earthworm (Eisenia fetida and Lumbricus terrestris) health were assessed using 14 day toxicity assays (4 application rates between 85-340 kgN.ha-1) and with 48 hour avoidance tests. In general, the addition of digestate-based fertilisers resulted in no observable toxic effects and earthworms did not significantly avoid these materials when compared to a conventional fertiliser. However, earthworms mortality was observed with one of the ash-digestate blends applied at 340 kgN.ha-1, potentially linked to changes in soil pH and elements speciation .It is therefore crucial that the effects of the amendments on soil properties, and the implications this has for soil communities at all scales, is understood to ensure sustainable soil management in agriculture.
Analysing Structure Dynamics in Arable Soils using X-ray Micro-Tomography

NASA Astrophysics Data System (ADS)

Schlüter, S.; Weller, U.; Vogel, H.-J.

2009-04-01

Structure is a dynamic property of soil. It interacts with many biotic and abiotic features and controls various soil functions. We analyzed soil structure within different plots of the ''Static Fertilisation Experiment'' at the agricultural research station in Bad Lauchstaedt (Germany) using X-ray micro tomography. The aim was to investigate in how far different levels of organic carbon, increased microbial activity and enhanced plant growth affects structural properties of an arable soil. Since 106 years one plot has experienced a constant application of farmyard manure and fertilisers, whereas the other has never been fertilised in this period. Intact soil cores from the chernozem soil at the two plots were taken from a depth of 5 to 15 cm (Ap-horizon) and 35 to 45 cm (Ah-horizon) to analyse structural changes with depth and in two different seasons (spring and summer) to investigate structure dynamics. The pore structure was analysed by quantifying the mean geometrical and topological characteristics of the pore network as a function of pore size. This was done by a combination of Minkowski functionals and morphological size distibution. For small structural features close to the image resolution the results clearly depend on the applied filtering technique and segmentation thresholds. Therefore the application of different image enhancement techniques is discussed. Furthermore, a new method for an automated determination of grey value thesholds for the segmentation of CT-images into pore space and solid is developed and evaluated. We highlight the relevance of image resolution for structure analysis. Results of the structure analysis reveal that the spring samples of the ploughed layer (Ap-horizon) from the fertilised plot have significantly higher macroporosities (P < 0.05) than those from the non-fertilised plot. The internal connectivity of the pore network is better in the fertilised plot and the pore size distribution was found to be different, too. The differences in porosity and pore connectivity increase from spring to summer. Both plots were compacted by a rolling machine in late winter. So the difference in structure dynamics is interpreted as an enhanced structure resiliency in the fertilised and carbon enriched plot after that compaction. A comparison with porosity features of a nearby reference profil under grassland demonstrates that the impact of tillage on pore structure is higher than the different contents in organic carbon. The carbon enriched horizon beneath the ploughed layer (Ah-horizon) shows no differences in pore size distribution and connectivity as a function of fertilisation. Thus, at that soil depth, no long-term effects of fertilization in terms of soil structure are detectable. Obviously, the highly different energy input during 106 years only affects the structure of the top soil.

Why Seedlings Die: Linking Carbon and Water Limitations to Mechanisms of Mortality During Establishment in Conifer Seedlings

NASA Astrophysics Data System (ADS)

Reinhardt, K.; Germino, M. J.; Kueppers, L. M.; Mitton, J.; Castanha, C.

2012-12-01

BACKGROUND Recent ecophysiological studies aimed at explaining adult tree mortality during drought have examined the carbon (C)-exhaustion compared to the hydraulic-failure hypotheses for death. Prolonged drought leads to durations of stomatal closure (and thus limited C gain), which could result in long periods of negative C balance and fatal reductions in whole-plant C reserves (i.e., available non-structural carbohydrates ["NSC"]). Alternatively, C reserves may not decrease much but could become increasingly inaccessible to sink tissues in long dry-periods due to impediments to translocation of photosynthate (e.g., through disruption of hydrostatic pressure flow in phloem). As C reserves decline or become inaccessible, continued maintenance respiration has been hypothesized to lead to exhaustion of NSC after extended durations of drought, especially in isohydric plant species. On the other hand, hydraulic failure (e.g., catastrophic xylem embolisms) during drought may be the proximate cause of death, occurring before true C starvation occurs. Few studies have investigated specifically the mechanism(s) of tree death, and no published studies that we know of have quantified changes in NSC during mortality. EXPERIMENTAL DESIGN AND HYPOTHESES We conducted two studies that investigated whole-tree and tissue-specific C relations (photosynthetic C gain, respiration, dry-mass gain, and NSC pools) in Pinus flexilis seedlings during the initial establishment phase, which is characterized by progressive drought during summer. We measured survival, growth and biomass allocation, and C-balance physiology (photosynthetic C-gain and chlorophyll fluorescence, respiration C-use, and NSC concentrations) from germination to mortality. We hypothesized that 1) stomatal and biochemical limitations to C gain would constrain seedling survival (through inadequate seasonal C-balance), as has been shown for conifer seedlings near alpine treeline; 2) hydraulic constraints (embolisms and/or reduced hydraulic conductance), associated with roots unable to escape the seasonal drying front in the soil, would limit seedling survival at least as much as C-balance dysfunction; and 3) seedling mortality would not be due to exhaustion of whole-plant NSC, as suggested by appreciable NSC in dead conifer seedlings reported in alpine treeline studies. RESULTS AND INTERPRETATIONS Preliminary results suggest that photosynthesis, fluorescence, and whole-tree NSC remained high until mortality, when plant water potentials decreased below -5 MPa. As seedlings approached mortality, NSC concentrations (both soluble sugars and starch) in roots decreased from ~9% to <3% of dry-mass. In aboveground tissues, NSC concentrations also declined initially (from ~12% to 3% of dry-mass), but then increased in needles (up to 8% dry-mass) and especially stems (up to 16% dry-mass), suggesting impediments to phloem-translocation in stems. Thus, seedling death could not be directly attributed to dysfunction of C-balance physiology, or exhaustion of NSC at the whole-plant level. We propose that hydraulic failure was likely the proximate cause of mortality under the conditions we evaluated, and drought-induced inhibition of NSC transport to roots may ultimately undermine the ability of seedlings to tap progressively deeper water sources during summer drying.
Effects of N and P fertilisation on greenhouse gas (GHG) production in floodplain fen peat: A microcosm fertilisation experiment.

NASA Astrophysics Data System (ADS)

Stanley, Kieran; Heppell, Catherine; Belyea, Lisa; Baird, Andrew

2016-04-01

Biogeochemical and hydrological cycles are being significantly perturbed by anthropic activities altering atmospheric mole fractions of greenhouse gases (GHG) and increasing global temperatures. With the intensification of the hydrological cycle, lowland areas, such as floodplain fens, may be inundated more frequently. Rivers in agricultural catchments have the potential to pollute floodplain fens with significant amounts of nitrogen (N) and phosphorus (P); however, the effects of short-term (< 15 days) N and P fertilisation via fluvial inundation on GHG emissions from floodplain fens are poorly understood. The aim of this research was to determine how N (51 mg L-1 NO3-N) and P (1.4 mg L-1 PO43--P) additions may alter GHG (CO2, CH4, and N2O) production in floodplain fens of contrasting nutrient status under anaerobic conditions. A five-level (control, glucose (G), N+G, P+G, and N+P+G), fully-factorial microcosm experiment was designed and undertaken in Spring 2013 with peat from two floodplain fens under conservation management with similar vegetation (from Norfolk, United Kingdom). One site receives a higher nutrient load than the other and has a historical legacy of higher N and P contents within the peat. Results from the experiment showed no significant difference in CO2 production between the control and fertilised treatments from 0 to 96 hours, but a significant difference between treatments (ANCOVA, between factors: treatment and site; covariate: time; F4,419 = 11.844, p < 0.001) and site (F1,149 = 5.721, p = 0.017) from 96 hours to in the end of the experiment due to fermentation. N2O production only occurred in samples fertilised with N (N+G and N+P+G) due to denitrification. Rates of N2O production were significantly greater in samples from the lower-nutrient site in comparison to the nutrient-rich site (t12= 6.539, p < 0.001 and t12= 7.273, p < 0.001 for N+G and N+P+G fertilised samples, respectively). Fertilisation with N and P had different effects on CH4 production. Samples fertilised with P+G had the highest CH4 production (ANCOVA, between factors: treatment and site; covariate: time; F4,120= 15.026, p < 0.001). Samples fertilised with N (N+G and N+P+G) showed CH4 inhibition in comparison to G and P+G additions. CH4 production was significantly greater from the nutrient-rich peat than from the lower-nutrient peat (ANCOVA, between factors: treatment and site; covariate: time; F1,120= 38.646, p < 0.01). However, a decline in CH4 concentration in the microcosms suggests that CH4 oxidation occurred after 150 hours at the lower-nutrient site. Owing to the anaerobic conditions within the microcosms, aerobic methanotrophy cannot occur, suggesting anaerobic CH4 oxidation occurred along with denitrification. However, NO and N2 concentrations were not measured in this study, so this suggestion requires examination in future work.
Inter- and intrapopulation variation in the response of tree seedlings to drought: physiological adjustments based on geographical origin, water supply and species.

PubMed

Carevic, Felipe S; Delatorre-Herrera, José; Delatorre-Castillo, José

2017-09-01

Initiatives to restore natural ecosystems have had little success in arid and hyperarid ecosystems. In this context, the natural seedling establishment is particularly affected by drought patterns and climatic variability. Likewise, the effect of plant provenance on forest restoration success remains unclear, although previous studies have concluded that some seed locations might be better able to tolerate water stress. In this study, we examined the physiological mechanisms involved in the drought stress resistance of Prosopis tamarugo and Prosopis alba seedlings from different arid and hyperarid locations of the Atacama Desert in northern Chile. We measured the xylem water potential (Ψ), cuticular transpiration (E c ), specific leaf area (SLA) and pressure-volume curves at the intrapopulation and interpopulation levels of seedlings of both species subjected to three drought-induced treatments. In addition, plant characteristics such as seedling height (Sh), stem diameter (Sd), leaf biomass (Lb), root biomass (Rb) and seedling survival (Ss) were measured during the treatments. Seedlings of most hyperarid habitats had the highest values of Ψ and water content relative to the turgor loss point, as well as decreased SLA, especially during the strongest drought treatment. Ψ was strongly correlated with Sh in both species, and soil humidity was correlated with Sd. This study highlights the high variability of physiological responses to water stress in both species at the interpopulation and intrapopulation levels, which provides us with a powerful seed selection tool for future reforestation programmes aimed at the early selection and genetic improvement of species of the Prosopis genus.
Inter- and intrapopulation variation in the response of tree seedlings to drought: physiological adjustments based on geographical origin, water supply and species

PubMed Central

Delatorre-Herrera, José; Delatorre-Castillo, José

2017-01-01

Abstract Initiatives to restore natural ecosystems have had little success in arid and hyperarid ecosystems. In this context, the natural seedling establishment is particularly affected by drought patterns and climatic variability. Likewise, the effect of plant provenance on forest restoration success remains unclear, although previous studies have concluded that some seed locations might be better able to tolerate water stress. In this study, we examined the physiological mechanisms involved in the drought stress resistance of Prosopis tamarugo and Prosopis alba seedlings from different arid and hyperarid locations of the Atacama Desert in northern Chile. We measured the xylem water potential (Ψ), cuticular transpiration (Ec), specific leaf area (SLA) and pressure–volume curves at the intrapopulation and interpopulation levels of seedlings of both species subjected to three drought-induced treatments. In addition, plant characteristics such as seedling height (Sh), stem diameter (Sd), leaf biomass (Lb), root biomass (Rb) and seedling survival (Ss) were measured during the treatments. Seedlings of most hyperarid habitats had the highest values of Ψ and water content relative to the turgor loss point, as well as decreased SLA, especially during the strongest drought treatment. Ψ was strongly correlated with Sh in both species, and soil humidity was correlated with Sd. This study highlights the high variability of physiological responses to water stress in both species at the interpopulation and intrapopulation levels, which provides us with a powerful seed selection tool for future reforestation programmes aimed at the early selection and genetic improvement of species of the Prosopis genus. PMID:28948009
Steering nitrogen fertilisation by means of portable chlorophyll meter reduces nitrogen input and improves quality of fertigated cantaloupe (Cucumis melo L. var. cantalupensis Naud.).

PubMed

Gianquinto, Giorgio; Fecondini, Marco; Mezzetti, Mirco; Orsini, Francesco

2010-02-01

Farming is considered one of the main causes of land degradation and underground water pollution. The increased availability of agricultural inputs has led to a dramatic rise in yields, which has resulted in soil fertility spoilage and overuse of fertilisers. Therefore horticultural practice improvement must consider appropriate nitrogen (N) management. This paper reports results on the application of an optical diagnostic system (N-tester) to guide N fertilisation in muskmelon (Cucumis melo L.) over a 3 year trial. Results on fresh and postharvest quality are also presented. Fertilisation events mirrored increases in N-tester values during the season, and a significant linear relationship (R(2) = 0.628) was observed between N-tester readings and leaf chlorophyll content. The N-tester-guided fertilisation treatments were characterised by yields comparable to the control, but with significantly lower applications of N (down to 17-66% of the N distributed in the control). Moreover, the N-tester treatments yielded fruits with higher sugar content. This was also true after storage, when N-tester fruits also showed reduced weight loss associated with lower transpiration and ethylene emission rates. Through the use of 'spy plots' kept at optimal nutritional status and the adoption of a threshold for N application throughout the growing cycle of muskmelon, the N supply was significantly reduced. Therefore a correct application of N-tester allowed the plant N requirement to be reduced and the fruit sugar content and storability to be increased without adversely affecting the yield.
DNase I and II present in avian oocytes: a possible involvement in sperm degradation at polyspermic fertilisation.

PubMed

Stepińska, Urszula; Olszańska, Bozenna

2003-02-01

During polyspermic fertilisation in birds numerous spermatozoa enter the eggs, in contrast to the situation in mammals where fertilisation is monospermic. However, in birds only one of the spermatozoa which have entered an egg participates in zygote nucleus formation, while the supernumerary spermatozoa degenerate at early embryogenesis. Our previous work has demonstrated the presence in preovulatory quail oocytes of DNase I and II activities able to digest naked lambdaDNA/HindIII substrate in vitro. In the present studies, the activities of both DNases in quail oocytes at different stages of oogenesis and in ovulated mouse oocytes were assayed in vitro using the same substrate. Degradation of quail spermatozoa by quail oocyte extracts was also checked. Digestion of the DNA substrate was evaluated by electrophoresis on agarose gels. The activities of DNase I and II in quail oocytes increased during oogenesis and were the highest in mature oocytes. The activities were present not only in germinal discs but also in a thin layer of cytoplasm adhering to the perivitelline layer surrounding the yolk. At all stages of oogenesis the activity of DNase II was much higher than that of DNase I. DNA contained in spermatozoa was also degraded by the quail oocyte extracts under conditions optimal for both DNases. In contrast to what is observed in quail oocytes, no DNase activities were detected in ovulated mouse eggs; this is logical as they would be useless or even harmful in monospermic fertilisation. The possible role of DNase activities in avian oocytes, in degradation of accessory spermatozoa during polyspermic fertilisation, is discussed.
Quality of fresh-cut baby spinach grown under a floating trays system as affected by nitrogen fertilisation and innovative packaging treatments.

PubMed

Rodríguez-Hidalgo, Stephanie; Artés-Hernández, Francisco; Gómez, Perla A; Fernández, Juan Antonio; Artés, Francisco

2010-04-30

Alternative techniques for cultivation of leafy vegetables such as a floating tray system and unconventional gas mixtures for post-harvest active modified atmosphere packaging (MAP) could be of interest in the minimally processed vegetable industry. The combined effect of three pre-harvest fertilisation doses (8, 12 or 16 mmol N L(-1)) and three post-harvest MAP conditions (passive, super-atmospheric or N2O-enriched) on the main quality attributes of fresh-cut baby spinach leaves throughout 10 days at 5 degrees C was studied. After 8 days of shelf life, spinach leaves fertilised with 8 and 16 mmol N L(-1) and stored under N2O-enriched MAP showed the lowest microbial growth, with good sensory quality. Such combined treatments also preserved the total antioxidant capacity sampled at harvest (8 g ascorbic acid equivalent antioxidant capacity kg(-1) f.w.). A decrease of 10-20% in total vitamin C content regardless of N fertilisation and packaging treatment was found during shelf life. Total phenolics content at harvest was 2 g gallic acid equivalents kg(-1) f.w., which was slightly decreased or preserved during shelf life while total chlorophylls were preserved for all treatments assayed around 550 mg kg(-1) f.w. No clear effect of fertilisation doses was observed during post-harvest storage on overall quality of fresh-cut baby spinach leaves, while N2O-enriched atmospheres seems to be a promising alternative to passive MAP for extending shelf life.
Pre-selection by double layer density gradient centrifugation improves the fertilising capacity of frozen-thawed, capacitated stallion sperm.

PubMed

Morató, Roser; Soares, Juleide M De Souza; Orero, Guifré; Mogas, Teresa; Miró, Jordi

2013-06-01

The effect of combining double layer density gradient centrifugation (DL-DGC) with different capacitation treatments on the fertilising capacity of frozen-thawed stallion sperm was examined via a heterologous assay involving in vitro-matured, zona pellucida-free bovine oocytes. In a first experiment, aliquots of frozen-thawed stallion sperm were subjected to one of five capacitation treatments without DL-DGC - ionomycin at 1.0μM, 0.1μM, 0.05μM or 0.01μM, or caffeine at 200μg/mL. The fertilising capacity of the semen was then assessed at 18h by staining the above oocytes with 4,6-diamidino-2-phenylindole (DAPI) and examining for sperm penetration, the number of penetrated spermatozoa per oocyte, and male pronucleus formation. In a second experiment, aliquots of frozen-thawed stallion sperm were subjected to DL-DGC selection - or not - and then further subjected to the two best capacitation treatments (0.1μM and 0.05μM ionomycin). The fertilising capacity of the semen was then determined as above. The DL-DGC/capacitated sperm samples showed the highest mean penetration rates: 24.16% following capacitation with 0.1μM ionomycin, and 12.21% following capacitation with 0.05μM ionomycin. The capacitated but non-DL-DGC-selected sperm returned significantly lower values: 6.26% and 7.02% for the same ionomycin treatments respectively. These findings suggest that combining DL-DGC selection with ionomycin capacitation improves the fertilising capacity of frozen-thawed stallion sperm. Copyright © 2013 Elsevier B.V. All rights reserved.
The Human Fertilisation and Embryology Act of 1990 and Assessment for Parenthood: In Whose Best Interests?

ERIC Educational Resources Information Center

Ryburn, Murray; Fleming, Annette

1993-01-01

Britain's Human Fertilisation and Embryology Act provides for the assessment of adults for parenthood on both medical and social grounds, justified by concern for the welfare of the child. Compares these assessments with those undertaken in the adoption process and questions the utility of such decisions for the welfare of the children involved.…
Phosphorus transformations in plant-based and bio-waste materials induced by pyrolysis.

PubMed

Robinson, James Stephen; Baumann, Karen; Hu, Yongfeng; Hagemann, Philipp; Kebelmann, Lutz; Leinweber, Peter

2018-01-01

Strategies are needed to increase the sustainability of phosphorus (P) fertiliser management in agriculture. This paper reports on the potential of pyrolysis treatment to recycle P from renewable materials previously regarded as wastes. The study used K-edge X-ray absorption near-edge structure (XANES) spectroscopy to examine chemical forms of P in the waste feedstock materials and corresponding biochars (pyrolysis at 480-500 °C) of four ligno-cellulosic, plant-based residues and five relatively P-rich livestock and water-treatment by-products, to acquire information on changes in potential P fertiliser value. Pyrolysis enriched P in the biochars by factors of 1.3-4.3, thus offering wide-ranging P fertiliser potential. XANES spectroscopy revealed hydroxyapatite (HAP) as one of the dominant chemical P compounds in the feedstocks, ranging from 14% (rice husks) to 98% (animal bone) of total P. For most materials, pyrolysis increased the proportion of HAP, and pyrophosphates were generated in several cases. These alterations possibly lead to diversity in the P solubility characteristics of the biochars if used as soil amendments; this is an important property of environmentally sound P fertilisers.
Suspended sediments limit coral sperm availability

PubMed Central

Ricardo, Gerard F.; Jones, Ross J.; Clode, Peta L.; Humanes, Adriana; Negri, Andrew P.

2015-01-01

Suspended sediment from dredging activities and natural resuspension events represent a risk to the reproductive processes of coral, and therefore the ongoing maintenance of reefal populations. To investigate the underlying mechanisms that could reduce the fertilisation success in turbid water, we conducted several experiments exposing gametes of the corals Acropora tenuis and A. millepora to two sediment types. Sperm limitation was identified in the presence of siliciclastic sediment (230 and ~700 mg L−1), with 2–37 fold more sperm required to achieve maximum fertilisation rates, when compared with sediment-free treatments. This effect was more pronounced at sub-optimum sperm concentrations. Considerable (>45%) decreases in sperm concentration at the water’s surface was recorded in the presence of siliciclastic sediment and a >20% decrease for carbonate sediment. Electron microscopy then confirmed sediment entangled sperm and we propose entrapment and sinking is the primary mechanism reducing sperm available to the egg. Longer exposure to suspended sediments and gamete aging further decreased fertilisation success when compared with a shorter exposure. Collectively, these findings demonstrate that high concentrations of suspended sediments effectively remove sperm from the water’s surface during coral spawning events, reducing the window for fertilisation with potential subsequent flow-on effects for recruitment. PMID:26659008
Suspended sediments limit coral sperm availability.

PubMed

Ricardo, Gerard F; Jones, Ross J; Clode, Peta L; Humanes, Adriana; Negri, Andrew P

2015-12-14

Suspended sediment from dredging activities and natural resuspension events represent a risk to the reproductive processes of coral, and therefore the ongoing maintenance of reefal populations. To investigate the underlying mechanisms that could reduce the fertilisation success in turbid water, we conducted several experiments exposing gametes of the corals Acropora tenuis and A. millepora to two sediment types. Sperm limitation was identified in the presence of siliciclastic sediment (230 and ~700 mg L(-1)), with 2-37 fold more sperm required to achieve maximum fertilisation rates, when compared with sediment-free treatments. This effect was more pronounced at sub-optimum sperm concentrations. Considerable (>45%) decreases in sperm concentration at the water's surface was recorded in the presence of siliciclastic sediment and a >20% decrease for carbonate sediment. Electron microscopy then confirmed sediment entangled sperm and we propose entrapment and sinking is the primary mechanism reducing sperm available to the egg. Longer exposure to suspended sediments and gamete aging further decreased fertilisation success when compared with a shorter exposure. Collectively, these findings demonstrate that high concentrations of suspended sediments effectively remove sperm from the water's surface during coral spawning events, reducing the window for fertilisation with potential subsequent flow-on effects for recruitment.
Allelopathic and bioherbicidal potential of Cladonia verticillaris on the germination and growth of Lactuca sativa.

PubMed

Tigre, R C; Silva, N H; Santos, M G; Honda, N K; Falcão, E P S; Pereira, E C

2012-10-01

Responses to germination and initial growth of Lactuca sativa (lettuce) submitted to organic extracts and purified compounds of Cladonia verticillaris ("salambaia") were analyzed in this work. The experiments were conducted in laboratory conditions using extracts and pure compounds at different concentrations. None of the assays showed any influence on the germination of L. sativa seeds using C. verticillaris extracts; however, modifications in leaf area and seedling hypocotyl and root development occurred. In the growth experiments, seedlings exposed to ether or acetone extract showed diminished hypocotyl growth in detriment to the root stimulus, compared to controls. Increases in extract concentrations led to the formation of abnormal seedlings. To determine the allelochemicals of C. verticillaris, its principal components, fumarprotocetraric and protocetraric acids, were isolated and then analyzed by high performance liquid chromatography (HPLC). When the seedlings were exposed to the two acids separately, presented increased leaf area at all concentrations. In contrast, hypocotyl and root stimulus was observed only in the presence of protocetraric acid at different concentrations. Fumarprotocetraric as well as protocetraric acids, isolated and purified from C. verticillaris and Parmotrema dilatatum respectively, influenced the development of L. sativa seedlings at high concentrations, indicating a possible bioherbicide potential of these acids. Crown Copyright © 2012. Published by Elsevier Inc. All rights reserved.
Triticale powdery mildew: population characterization and wheat gene efficiency.

PubMed

Bouguennec, Annaig; Trottet, Maxime; du Cheyron, Philippe; Lonnet, Philippe

2014-01-01

Powdery mildew has emerged on triticale in the early 2000s in many locations, probably due to a host range expansion of the wheat formae speciales, Blumeria graminis f.sp. tritici. Many triticale cultivars are highly susceptible to powdery mildew, mainly in seedling stage, revealing a probably narrow genetic basis for powdery mildew resistance genes (Pm). Moreover, as Blumeria graminis is an obligate biotrophic fungus, it is very time consuming and difficult to maintain powdery mildew isolates for a non-specialized laboratory and populations can evolve. In order to identify wheat Pm genes efficient against natural populations of powdery mildew, wheat differential hosts and triticale seedlings were inoculated below susceptible triticale crop naturally contaminated by mildew, in several locations and several years. Symptoms on seedlings were measured after approximately two weeks of incubation in favorable fungus growth conditions. According to these data, we classified the Pm genes presents in our wheat differential hosts set in 3 classes: Pm already overcame by triticale powdery mildew, Pm having variable effects and Pm still efficient against triticale mildew. Data on triticale seedlings allowed us to identify some few triticale cultivars resistant to Blumeria graminis in seedling stage. We will try to identify Pm genes present in those cultivars next year by testing them with the characterized isolates of powdery mildew from Gent University. Nevertheless, interspecific crossing of wheat, resistant to powdery mildew in seedling stage, and rye have been initiated to introduce potentially interesting genes for resistance in triticale.
Do key dimensions of seed and seedling functional trait variation capture variation in recruitment probability?

PubMed

Larson, Julie E; Sheley, Roger L; Hardegree, Stuart P; Doescher, Paul S; James, Jeremy J

2016-05-01

Seedling recruitment is a critical driver of population dynamics and community assembly, yet we know little about functional traits that define different recruitment strategies. For the first time, we examined whether trait relatedness across germination and seedling stages allows the identification of general recruitment strategies which share core functional attributes and also correspond to recruitment outcomes in applied settings. We measured six seed and eight seedling traits (lab- and field-collected, respectively) for 47 varieties of dryland grasses and used principal component analysis (PCA) and cluster analysis to identify major dimensions of trait variation and to isolate trait-based recruitment groups, respectively. PCA highlighted some links between seed and seedling traits, suggesting that relative growth rate and root elongation rate are simultaneously but independently associated with seed mass and initial root mass (first axis), and with leaf dry matter content, specific leaf area, coleoptile tissue density and germination rate (second axis). Third and fourth axes captured separate tradeoffs between hydrothermal time and base water potential for germination, and between specific root length and root mass ratio, respectively. Cluster analysis separated six recruitment types along dimensions of germination and growth rates, but classifications did not correspond to patterns of germination, emergence or recruitment in the field under either of two watering treatments. Thus, while we have begun to identify major threads of functional variation across seed and seedling stages, our understanding of how this variation influences demographic processes-particularly germination and emergence-remains a key gap in functional ecology.
Total ammoniacal nitrogen biofiltration of wastewaters from aquaculture systems using Macrocystis spp.

PubMed

Bravo, R; Segovia, E; Guerrero, L; Montalvo, S; Barahona, A; Borja, R

2013-01-01

The results of total ammoniacal nitrogen (NH(3) + NH(4) (+)) removal in aquaculture systems using two experimental sets, aquatic seedlings produced in laboratory controlled conditions and wild seaweed (Macrocystis spp.) in reproductive state, are shown in this work. Biofiltration assays were carried out using a load of total ammoniacal nitrogen (TAN) of 1 mg/L. Absorption rates were measured taking into account a previous surface characterization, which gave values of 44 ± 14 cm(2)/g and 18 ± 6 cm(2)/g for aquatic seedlings and wild algae, respectively. The following parameters were measured during the experimental runs: temperature, pH, O(2), illuminance or light intensity, salinity and total solids. TAN removals of 61% and 70% were achieved for the seedlings and Macrocystis spp., respectively, after 17 h of treatment. The TAN absorption results were expressed as a function of surface and mass achieving the following values: 3.0 nmol N cm(-2) h(-1) and 111 nmol N g(-1) h(-1) for the seedlings, and 6.9 nmol N cm(-2) h(-1) and 122.4 nmol N g(-1) h(-1) for the macroalgae. In the light of these biofiltration processes, the initial TAN concentration decreased by 90% for the seedlings and wild algae over approximately 110 and 41 h, respectively. In addition, TAN removals achieved with Macrocystis spp. were always higher than those obtained with aquatic seedlings for the same operating periods.
Phytotoxicity of glyphosate in the germination of Pisum sativum and its effect on germinated seedlings

PubMed Central

2017-01-01

The present study evaluated the effects of glyphosate on Pisum sativum germination as well as its effect on the physiology and biochemistry of germinated seedlings. Different physico-chemical biomarkers, viz., chlorophyll, root and shoot length, total protein and soluble sugar, along with sodium and potassium concentration, were investigated in germinated seedlings at different glyphosate concentrations. This study reports the influence of different concentrations of glyphosate on pea seeds and seedlings. Physicochemical biomarkers were significantly changed by glyphosate exposure after 15 days. The germination of seedlings under control conditions (0 mg/L) was 100% after 3 days of treatment but at 3 and 4 mg/L glyphosate, germination was reduced to 55 and 40%, respectively. Physiological parameters like root and shoot length decreased monotonically with increasing glyphosate concentration, at 14 days of observation. Average root and shoot length (n=30 in three replicates) were reduced to 14.7 and 17.6%, respectively, at 4 mg/L glyphosate. Leaf chlorophyll content also decreased, with a similar trend to root and shoot length, but the protein content initially decreased and then increased with an increase in glyphosate concentration to 3 mg/L. The study suggests that glyphosate reduces the soluble sugar content significantly, by 21.6% (v/v). But internal sodium and potassium tissue concentrations were significantly altered by glyphosate exposure with increasing concentrations of glyphosate. Biochemical and physiological analysis also supports the inhibitory effect of glyphosate on seed germination and biochemical effects on seedlings. PMID:28728354
Adding Value to Ash and Digestate (AVAnD): Performance of Novel Soil Amendents on the Soil-Plant System Under Glasshouse Conditions

NASA Astrophysics Data System (ADS)

Lag-Brotons, Alfonso; Marshall, Rachel; Herbert, Ben; Hurst, Lois; Ostle, Nick; Dodd, Ian; Quinton, John; Surridge, Ben; Aiouache, Farid; Semple, Kirk T.

2017-04-01

Resource recovery from waste plays a central role in strategies tackling current worldwide sustainability problems. In this sense, two waste streams derived from bioenergy production (anaerobic digestion and incineration), digestate [D] and biomass ash [A], may be especially valuable within agriculture. These materials offer complementary plant nutrient profiles for alternative fertiliser production (i.e. nitrogen [N] from D and phosphorus [P] from A). In addition, incorporating these materials into the soil could impact upon several soil/plant characteristics, and have positive effects on ecosystem services (eg. nutrient cycling). Therefore, this present work assessed the effects of A/D blends on the soil-plant system under controlled conditions (glasshouse). The overarching aim of "Adding Value to Ash and Digestate [AVAnD]" project is to identify novel nutrient-recycling pathways to maximise soil quality and crop productivity utilising waste streams derived from bioenergy production. Two pot experiments of 6 weeks duration were carried out [Exp. A and Exp. B] using contrasting agricultural soils (neutral loam and sandy acidic soil) and wheat as the crop. A factorial randomised block design was selected, with fertilisation treatment and soil condition (planted/unplanted) as factors. Fertilisation treatments (n=13) were applied at a rate of 63/60 kg N/P2O5 per ha and comprised: control ([C], no fertilisation), urea [U], urea+superphosphate [U+P], fly ash [A1], bottom ash [A2], U+A1; U+A2, anaerobic digestates [D1, D2] and ash/digestate blends [D1A1, D1A2, D2A1, D2A2]. Each block (n=5) contained 8 planted and 5 unplanted pots (104 planted + 65 unplanted experimental units). At the end of the experiment, all the plants were assessed for morphometric traits, while for tissue elemental analyses the total number of replicates per treatment was randomly reduced (n=5/treatment). Soil physico-chemical properties (i.e. available nitrogen, pH) were assessed in unplanted and selected planted pots. Differences in plant growth were primarily dependant on soil type and secondarily on fertiliser type. In Exp. A, adding digestate-based treatments resulted in comparable biomass and N levels (concentration and uptake) to that of inorganic fertilisers (U+P). In Exp. B, growth was mainly related to soil pH, with higher biomass in those treatments containing A1. In relation to soil properties, the main effects were attributed to pH variation and increase of available N- / P- and EC. Based on these results, these novel materials and inorganic fertilisers induced similar effects in the soil-plant system, thus suggesting inorganic fertilisers could potentially be replaced. However, further research under field conditions, including other soil types, is required to corroborate the value of these A/D blends as land conditioners.
Influence of nonuniform magnetic fields on orientation of plant seedlings in microgravity conditions

NASA Astrophysics Data System (ADS)

Nechitailo, G. S.; Mashinsky, A. L.; Kuznetsov, A. A.; Chikov, V. M.; Kuznetsov, O. A.

2001-01-01

Experiments on the spatial behavior of the flax ( Linum usitatissimum, L.) seedlings in a nonuniform magnetic field were conducted on the orbital space stations «Salutå and «Mirå. This field can displace sensory organelles (statoliths) inside receptor cells and such displacement should cause a physiological reaction of the plant - tropistic curvature. Experiments were conducted in the custom-built «Magnetogravistatå facility, where seeds were germinated and grown for 3-4 days in a magnetic field with the dynamic factor grad(H 2/2)≈ 10 7 Oe 2/cm, then fixed on orbit and returned to Earth for analysis. It was found, that 93% of the seedlings were oriented in the field consistently with curvature in response to displacement of statoliths along the field gradient by ponderomotive magnetic forces, while control seedlings grew in the direction of the initial orientation of the seed. This suggests, that gravity receptors of plants recognized magnetic forces on statoliths as gravity, and that gravity stimulus can be substituted for plants by a force of a different physical nature.
[Allelopathy autotoxicity effects of aquatic extracts from rhizospheric soil on rooting and growth of stem cuttings in Pogostemon cablin].

PubMed

Tang, Kun; Li, Ming; Dong, Shan; Li, Yun-qi; Huang, Jie-wen; Li, Long-ming

2014-06-01

To study the allelopathy effects of aquatic extracts from rhizospheric soil on the rooting and growth of stem cutting in Pogostemon cablin, and to reveal its mechanism initially. The changes of rhizogenesis characteristics and physic-biochemical during cutting seedlings were observed when using different concentration of aquatic extracts from rhizospheric soil. Aquatic extracts from rhizospheric soil had significant inhibitory effects on rooting rate, root number, root length, root activity, growth rate of cutting with increasing concentrations of tissue extracts; The chlorophyll content of cutting seedlings were decreased, but content of MDA were increased, and activities of POD, PPO and IAAO in cutting seedlings were affected. Aquatic extracts from rhizospheric soil of Pogostemon cablin have varying degrees of inhibitory effects on the normal rooting and growth of stem cuttings.

Effects of fertilization on phosphorus pools in the volcanic soil of a managed tropical forest

Treesearch

Dean F. Meason; Travis W. Idol; J.B. Friday; Paul G. Scowcroft

2009-01-01

Acacia koa forests benefit from phosphorus fertilisation, but it is unknown if fertilisation is a short or long term effect on P availability. Past research suggests that P cycling in soils with high P sorption capacity, such as Andisols, was through organic pathways. We studied leaf P and soil P fractions in a tropical forest Andisol for 3 years...
Somatic symptoms, sleep disturbance and psychological distress among women undergoing oocyte pick-up and in vitro fertilisation-embryo transfer.

PubMed

Lin, Ya-Hui; Chueh, Ke-Hsin; Lin, Jia-Ling

2016-06-01

This study investigated the relationship between somatic symptoms, sleep disturbance and psychological distress in women who underwent oocyte pick-up and in vitro fertilisation-embryo transfer. According to worldwide research, women receiving assisted reproductive technologies may suffer from somatic and psychological symptoms and even experience sleep disturbance. Apparently, the guilt of infecundity forces Asian women to conceal this scenario and delay the time at which they accept medical assistance and mental support. A longitudinal study. The subjects in this study were infertile female patients who received oocyte pick-up and in vitro fertilisation-embryo transfer therapies in a hospital in northern Taiwan. Data were collected via a structured questionnaire, including somatic symptoms, Pittsburgh Sleep Quality Index and a five-item brief symptom rating scale. Data were analysed using the McNemar's test, Wilcoxon Sign Rank and fully entered multiple regression with spss version 20.0 software. The mean age of 100 participants was 34·54 (SD = 3·94) years old. They experienced abdominal distention, breast engorgement, nausea, faintness, diarrhoea, sleep disturbance and psychological distress when they received in vitro fertilisation-embryo transfer; these results were apparently higher than those receiving oocyte pick-up. In addition, sleep disturbance was the most significant factor involved in psychological distress during oocyte pick-up and in vitro fertilisation-embryo transfer therapies. The most serious indicator of the women's psychological distress during oocyte pick-up and in vitro fertilisation-embryo transfer treatment is anxiety. Sleep disturbance was the most significant factor involved in the psychological distress of women having problems with conception. Assisted reproductive technologies nurses can assess women's psychological distress by caring for their sleep disturbance without directly exploring their mood state. Moreover, these medical personnel should understand infertile female patients' psychological distress is mainly associated with their sleep disturbance. Developing various strategies to improve both sleep quality and psychological distress for infertile female patients should be recognised in future studies. © 2016 John Wiley & Sons Ltd.
Challenges in forest reclamation of marginal lands: a balance between site conditions and seedling quality

NASA Astrophysics Data System (ADS)

Landhäusser, Simon

2017-04-01

Forest loss and degradation is occurring worldwide, but at the same time efforts in forest restoration are ever increasing. While approaches to restoration often follow specific stakeholder objectives, regional climates and the degree of site degradation also play an important role in the prioritization of restoration efforts. Often the restoration of degraded lands can satisfy only few measurable objectives; however, to design and restore resistant and resilient ecosystems that can adapt to changing conditions, there is a need for new and adaptive management approaches. Mining and other resource extraction industries are affecting more and more forested areas worldwide. A priority in the reclamation and certification of forest lands disturbed by industrial activity is their expeditious redevelopment to functioning forests. To rehabilitate these heavily disturbed areas back to forest ecosystems, planting of trees remains one of the most effective strategies for the redevelopment of a continuous tree canopy on a site. It is well understood that access to good quality seedling stock is essential to achieve establishment success and early growth of seedlings. However, most reclamation areas have challenging initial site conditions and these conditions are often not a single factor but a combination of factors that can be additive or synergistic. Therefore successful forest restoration on degraded lands needs to consider multiple objectives and approaches to minimize trade-offs in achieving these objectives. To meet these demands, new methods for the production and evaluation of seedling stock types are needed to ensure that that seedlings are fit to grow on a wide range of site conditions or are particularly designed to grow in very specific conditions. Generally, defining seedling quality is difficult as it is species specific and results have been mixed; likely influenced by site conditions, further reiterating the need to carefully evaluate sites allowing appropriate seedling qualities to be identified. In this presentation, I will show results from a range of studies that explored the role of seedling characteristics in response to challenging site conditions and explore the need for a balance between the recognition and improvement of limiting site conditions and the availability of quality seedling stock in forest restoration.
Tree recruitment and survival in rivers: Influence of hydrological process

USGS Publications Warehouse

Dorava, J.M.; Milner, A.M.

2000-01-01

The findings of a 14-year study of tree reproduction and survival in the Platte River, Nebraska, are presented. The study was initiated in 1985 to determine the causes and remedies of woodland expansion and channel narrowing, which have reduced potential roosting habitat for migratory avifauna such as the whooping crane and sandhill crane. A total of 296 relocatable sites, constituting some 600 plots with Populus and Salix seedlings, was selected and sampled within two reaches near Shelton and Odessa, Nebraska. The fate of some 37 000 tree seedlings was monitored within the plot network. Tree recruitment is controlled largely by stream flow in June. Populus and Salix produce large numbers of seedlings in the river bed in most years, indicating the potential for high rates of woodland expansion. On average, in only 1 year in 7 is stream flow in June high enough to preclude Populus and Salix recruitment. Seedling mortality is dominated by two environmental factors: summer stream flow pulses from thunderstorms, which erode or bury new germinants, and river bed restructuring by moving ice in winter. A third factor, seedling mortality by desiccation during summer droughts, does occur but at a low frequency. Plots of seedlings had extremely low survival rates over the course of the study. Forty-two per cent of the plots lost all seedlings by the first remeasurement (July to September), 36% by the second measurement (May), and 10% by the third remeasurement (July). Thus nearly 90% of the plots had lost all tree seedlings by the end of the first year. These results explain why the Platte River has come into dynamic equilibrium with respect to the balance between active channel and woodland area. Low rates of new woodland expansion are counterbalanced by erosion of established woodland. The demographic approach to studying ecohydrology can be adapted to monitor the effectiveness of prescribed flows as insurance against future narrowing. Flows prescribed at key times to raise seedling mortality rates are recommended to maintain or widen channels, rather than mechanical clearing of established woodland. Copyright ?? 2000 John Wiley & Sons, Ltd.
Tree recruitment and survival in rivers: influence of hydrological processes

NASA Astrophysics Data System (ADS)

Carter Johnson, W.

2000-10-01

The findings of a 14-year study of tree reproduction and survival in the Platte River, Nebraska, are presented. The study was initiated in 1985 to determine the causes and remedies of woodland expansion and channel narrowing, which have reduced potential roosting habitat for migratory avifauna such as the whooping crane and sandhill crane.A total of 296 relocatable sites, constituting some 600 plots with Populus and Salix seedlings, was selected and sampled within two reaches near Shelton and Odessa, Nebraska. The fate of some 37 000 tree seedlings was monitored within the plot network.Tree recruitment is controlled largely by stream flow in June. Populus and Salix produce large numbers of seedlings in the river bed in most years, indicating the potential for high rates of woodland expansion. On average, in only 1 year in 7 is stream flow in June high enough to preclude Populus and Salix recruitment.Seedling mortality is dominated by two environmental factors: summer stream flow pulses from thunderstorms, which erode or bury new germinants, and river bed restructuring by moving ice in winter. A third factor, seedling mortality by desiccation during summer droughts, does occur but at a low frequency.Plots of seedlings had extremely low survival rates over the course of the study. Forty-two per cent of the plots lost all seedlings by the first remeasurement (July to September), 36% by the second measurement (May), and 10% by the third remeasurement (July). Thus nearly 90% of the plots had lost all tree seedlings by the end of the first year.
Measuring and Modeling Solute Transport in the Rootzone: Protecting the Receiving Water Environments of the Coral Atolls of Tonga

NASA Astrophysics Data System (ADS)

Clothier, B. E.; van der Velde, M.; Green, S. R.; Gee, G. W.; Manu, V.; Menoniti, V.; Vanclooster, M.

2005-05-01

Intensification of agriculture on the raised coral atolls of the Tongan archipelago, notably through squash-pumpkin production, has lead to increased use of agrichemicals. Agrichemicals, both fertilisers and pesticides, pose a risk to these fragile environments. Sustainable land-management practices are needed for small-island developing states. On Tongatapu, solutes leaving the rootzone of the squash can rapidly find their way to the underlying freshwater lenses. These lenses are hydraulically linked to the internal lagoon, and the fringing reefs. We have used buried, non-suction fluxmeters to monitor both the quantity and quality of drainage leaving the rootzone of squash. Fertiliser is traditionally applied at planting. During establishment of the squash in 2003, some 350 mm of rain fell, with 70 % of this leaving the rootzone of this permeable soil as drainage. The concentration of nitrate-N in the drainage water was measured at around 50 mg-N/L. All of the initial fertiliser dressing had been lost, along with N mineralised from the plowed-in grass. Pesticides are needed in humid tropical environments to control weeds, pests and diseases. These chemicals can leach though the rootzone to contaminate receiving waters. We modeled the transport and fate of the presticides used in squash production, and we developed a Decision Support Tool (DST). Our DST can be used to select the best pesticides for local conditions, to tailor practices for minimising leaching losses below the rootzone, and to avoid the build-up of residues in the soil. This project, funded by the European Union and NZAID, took a multi-disciplinary approach through measurement and modeling protocols. Our DST enabled us to engage the wider community and stakeholders. There has been increased awareness of the impacts and risks associated with productive land management in the fragile hydrological environments of this small-island developing state.
Influence of extended incubation time on Human sperm chromatin condensation, sperm DNA strand breaks and their effect on fertilisation rate.

PubMed

Ahmed, I; Abdelateef, S; Laqqan, M; Amor, H; Abdel-Lah, M A; Hammadeh, M E

2018-02-14

The purpose of this study was to determine influence of extended incubation time on sperm chromatin condensation and DNA strand breaks and their effect on fertilisation rate. Forty couples undergoing ICSI therapy were included. Semen was prepared by PureSperm gradient centrifugation and divided into two parts. The first part (G1) was used immediately for ICSI, whereas the second part (G2) was kept in the incubator at 37°C, 5% and 90% Humidity for 5 hr, and thereafter, the capacitated spermatozoa were used for ICSI. The TUNEL test and chromomycin CMA3 were used to evaluate the DNA strand breaks and chromatin condensation respectively. The percentage of condensed chromatin was 73.92 ± 12.70 in the group 1 and 81.13 ± 10.31% in group 2 (p = .001). However, the double-strand breaks were 11.15 ± 8.67% in G.1 and 16.30 ± 11.12% in G.2. (p = .001). Fertilisation rate in the (Group 1) was 62.45% and 69.17% in (Group 2). There was a positive correlation between condensed chromatin and fertilisation rate (r = 0.846, p = .001) and a negative correlation with DNA double-strand breaks (r = -0.802; p = .001). In conclusion, the prolonged sperm incubation (5 hr) leads to a higher chromatin condensation and to a significantly increased number of DNA strands double breaks with no influence on fertilisation rates. © 2018 Blackwell Verlag GmbH.
Assessing the impact of diclofenac, ibuprofen and sildenafil citrate (Viagra®) on the fertilisation biology of broadcast spawning marine invertebrates.

PubMed

Mohd Zanuri, Norlaila Binti; Bentley, Matthew G; Caldwell, Gary S

2017-06-01

Exposure to synthetic chemicals is a key environmental challenge faced by aquatic organisms. The time and dose effects of the pharmaceuticals diclofenac, ibuprofen, and sildenafil citrate on sperm motility and successful fertilisation are studied using the echinoderms, Asterias rubens and Psammechinus miliaris, and the polychaete worm Arenicola marina, all important components of the marine benthos. Motility was reduced for all species when exposed to diclofenac concentrations ≥0.1 μg/L. Exposure to ≥1.0 μg/L of ibuprofen affected only P. miliaris gametes and fertilisation success of A. marina. A. rubens and P. miliaris sperm increased in both percentage motility and swimming velocity when exposed to sildenafil citrate at concentrations ≥18 and ≥ 50 ng/L, respectively. Pre-incubation of sperm with sildenafil citrate significantly increased fertilisation success in A. rubens and P. miliaris but not in A. marina. Pre-incubated A. rubens oocytes fertilised successfully in ibuprofen. According to EU Directive 93/67/EEC, diclofenac is classified as a very toxic substance to gametes of A. rubens, P. miliaris, and A. marina (EC 50 = 100-1000 μg/L) while ibuprofen is classified as very toxic to gametes of P. miliaris but non-toxic to gametes of A. marina (EC 50 > 10,000 μg/L). The present study indicates that diclofenac exposure may have negative impacts on invertebrate reproductive success, whereas ibuprofen potentially may compromise P. miliaris reproduction. This study provides a valuable insight into the mechanisms that allow marine invertebrates to survive and reproduce in contaminated and changing habitats. Copyright © 2017 Elsevier Ltd. All rights reserved.
Pentoxifylline added to freezing or post-thaw extenders does not improve the survival or in vitro fertilising capacity of boar spermatozoa.

PubMed

Gil, María A; Hernandez, Marta; Roca, Jordi; Almiñana, Carmen; Lucas, Xiomara; Cuello, Cristina; Vazquez, Juan M; Martínez, Emilio A

2010-03-01

This study evaluated whether pentoxifylline added to freezing and thawing extenders influenced the function of boar spermatozoa. In Experiment 1, pooled ejaculated sperm-rich fractions were frozen in 0.5 ml straws after dilution in extender supplemented with pentoxifylline to a final concentration of 0, 2, 4, 8, 16 or 32 mM. The addition of 4, 8, 16 and 32 mM pentoxifylline to the freezing extender significantly decreased the progressive and total motility of spermatozoa. The percentage of viable spermatozoa with intact acrosomes as well as the penetration rate and the efficiency of fertilisation were significantly lower in pentoxifylline-treated groups compared with the untreated control. In Experiment 2, a pool of three straws with 'good' post-thaw sperm quality parameters and another three straws with 'poor' sperm quality were diluted in extender with 0, 1, 2, 4, 8, 16 or 32 mM pentoxifylline. Post-thaw samples with both 'good' and 'poor' sperm quality with 0, 2, 4, 8 and 16 mM were used to assess IVF parameters. The addition of pentoxifylline to post-thaw extender did not improve the post-thaw motility or viability of spermatozoa compared with the control. The in vitro penetration was higher (P<0.05) than the control for oocytes fertilised with spermatozoa that were thawed and incubated in extender with 4, 8 and 16 mM pentoxifylline. However, no differences were observed in the efficiency of fertilisation. We conclude that pentoxifylline, as a supplement added to the freezing extender, has a deleterious effect and that it does not improve the survival or in vitro fertilising efficiency of frozen-thawed boar spermatozoa when added after thawing.
May humic acids or mineral fertilisation mitigate arsenic mobility and availability to carrot plants (Daucus carota L.) in a volcanic soil polluted by As from irrigation water?

PubMed

Caporale, Antonio G; Adamo, Paola; Azam, Shah M G G; Rao, Maria A; Pigna, Massimo

2018-02-01

Carrot (Daucus carota L.) is a widely consumed root vegetable, whose growth and safety might be threatened by growing-medium arsenic (As) contamination. By this work, we evaluated the effects of humic acids from Leonardite and NPK mineral fertilisation on As mobility and availability to carrot plants grown for 60 days in a volcanic soil irrigated with As-contaminated water - representing the most common scenario occurring in As-affected Italian areas. As expected, the irrigation with As-contaminated water caused a serious toxic effect on plant growth and photosynthetic rate; the highest rate of As also inhibited soil enzymatic activity. In contrast, the organic and mineral fertilisation alleviated, at least partially, the toxicity of As, essentially by stimulating plant growth and promoting nutrient uptake. The mobility of As in the volcanic soil and thus its phytoavailability were differently affected by the organic and mineral fertilisers; the application of humic acids mitigated the availability of the contaminant, likely by its partial immobilisation on humic acid sorption sites - thus raising up the intrinsic anionic sorption capacity of the volcanic soil; the mineral fertilisation enhanced the mobility of As in soil, probably due to competition of P for the anionic sorption sites of the soil variable-charge minerals, very affine to available P. These findings hence suggest that a proper soil management of As-polluted volcanic soils and amendment by stable organic matter might mitigate the environmental risk of these soils, thus minimising the availability of As to biota. Copyright © 2017 Elsevier Ltd. All rights reserved.
Effects of organic fertilisation on sweet orange bearing trees

NASA Astrophysics Data System (ADS)

Roccuzzo, Giancarlo; Torrisi, Biagio; Canali, Stefano; Intrigliolo, Francesco

2010-05-01

In a study realised over a five year period (2001-2006) on orange bearing trees [Citrus sinensis (L.) Osbeck] cv. ‘Valencia late', grafted on sour orange (C. aurantium L.), four fertiliser treatments were applied: citrus by-products compost (CB), poultry manure (PM), livestock waste compost (LW) and mineral fertiliser (MF), as control. The trees, with the exception of MF treatment, were organically grown since 1994 in the experimental farm of CRA-ACM in Lentini, Sicily, and received the same N input every year. The research objectives were to evaluate the effect of long term repeated organic fertilisers application on i) soil fertility; ii) citrus bearing trees nutritional status by means of leaf analysis and iii) yield and fruit quality, determining parameters currently utilized to evaluate sweet orange production either for fresh consumption and processing. The CB treatment showed significantly higher values of Corg in soil than MF treatment (about 30%). Corg in PM and LW treatments was higher than MF treatment (13% and 20%, respectively), but these differences were not statistically significant either from the control treatment nor from the soil fertilised with CB. Similar trend was showed by the humic and fulvic C being the values of the CB treatment significantly higher than the control. PM and LW treatments had intermediate values, without statistical significance. The long term addition to soil of a quality compost (CB) with high C/N ratio increased the level of nutrients wich usually show low availability for citrus plants (P, Fe, Zn, Mn), as demonstrated by leaf analysis. No significant difference was noticed as far as yield was concerned, whereas CB treatment enhanced some fruit quality parameters.
Bioremediation by composting of heavy oil refinery sludge in semiarid conditions.

PubMed

Marín, José A; Moreno, José L; Hernández, Teresa; García, Carlos

2006-06-01

The present work attempts to ascertain the efficacy of low cost technology (in our case, composting) as a bioremediation technique for reducing the hydrocarbon content of oil refinery sludge with a large total hydrocarbon content (250-300 g kg(-1)), in semiarid conditions. The oil sludge was produced in a refinery sited in SE Spain The composting system designed, which involved open air piles turned periodically over a period of 3 months, proved to be inexpensive and reliable. The influence on hydrocarbon biodegradation of adding a bulking agent (wood shavings) and inoculation of the composting piles with pig slurry (a liquid organic fertiliser which adds nutrients and microbial biomass to the pile) was also studied. The most difficult part during the composting process was maintaining a suitable level of humidity in the piles. The most effective treatment was the one in which the bulking agent was added, where the initial hydrocarbon content was reduced by 60% in 3 months, compared with the 32% reduction achieved without the bulking agent. The introduction of the organic fertiliser did not significantly improve the degree of hydrocarbon degradation (56% hydrocarbon degraded). The composting process undoubtedly led to the biodegradation of toxic compounds, as was demonstrated by ecotoxicity tests using luminescent bacteria and tests on plants in Petri dishes.
Novel chelating agents for iron, manganese, zinc, and copper mixed fertilisation in high pH soil-less cultures.

PubMed

López-Rayo, Sandra; Nadal, Paloma; Lucena, Juan J

2016-03-15

Studies about simultaneous fertilisation with several micronutrients have increased in recent years, as Fe, Mn and Zn deficiencies may appear in the same culture conditions. In fertigation, the replacement of sulfates by synthetic chelates is essential in areas with high pH irrigation water and substrates. Ethylenediamine-N-(2-hydroxyphenylacetic acid)-N'-(4-hydroxyphenylacetic acid) (o,p-EDDHA) and ethylenediamine disuccinic acid (EDDS) are novel chelating agents whose efficacy in simultaneous fertilisation of Zn, Mn and Cu is unknown. This work evaluates the effectiveness of both ligands compared to traditional ligands (EDTA, HEEDTA and DTPA) applied as micronutrient chelate mixtures to soybean and navy bean plants grown in soil-less cultures at high pH by analysing the SPAD and micronutrient nutritional status, including the Composition Nutritional Diagnosis (CND) analysis tool. The application of micronutrients using o,p-EDDHA was more effective in providing Mn and Zn than traditional ligands or sulfates. The application using EDDS increased the Zn nutrition. The results are well correlated with the chemical stability of the formulations. The combined application of Mn and Zn as o,p-EDDHA chelates can represent a more effective source than traditional chelates in micronutrient fertiliser mixtures in soil-less cultures at a high pH. © 2015 Society of Chemical Industry.
Genotype Reconstruction of Paternity in European Lobsters (Homarus gammarus).

PubMed

Ellis, Charlie D; Hodgson, David J; André, Carl; Sørdalen, Tonje K; Knutsen, Halvor; Griffiths, Amber G F

2015-01-01

Decapod crustaceans exhibit considerable variation in fertilisation strategies, ranging from pervasive single paternity to the near-ubiquitous presence of multiple paternity, and such knowledge of mating systems and behaviour are required for the informed management of commercially-exploited marine fisheries. We used genetic markers to assess the paternity of individual broods in the European lobster, Homarus gammarus, a species for which paternity structure is unknown. Using 13 multiplexed microsatellite loci, three of which are newly described in this study, we genotyped 10 eggs from each of 34 females collected from an Atlantic peninsula in the south-western United Kingdom. Single reconstructed paternal genotypes explained all observed progeny genotypes in each of the 34 egg clutches, and each clutch was fertilised by a different male. Simulations indicated that the probability of detecting multiple paternity was in excess of 95% if secondary sires account for at least a quarter of the brood, and in excess of 99% where additional sire success was approximately equal. Our results show that multiple paternal fertilisations are either absent, unusual, or highly skewed in favour of a single male among H. gammarus in this area. Potential mechanisms upholding single paternal fertilisation are discussed, along with the prospective utility of parentage assignments in evaluations of hatchery stocking and other fishery conservation approaches in light of this finding.
Comparison of conventional in vitro fertilisation and intracytoplasmic sperm injection outcomes in patients with moderate oligoasthenozoospermia.

PubMed

Shuai, H-L; Ye, Q; Huang, Y-H; Xie, B-G

2015-06-01

The method of choice for assisted reproductive technology treatment in vitro fertilisation (IVF) or intracytoplasmic sperm injection (ICSI) is usually based on the evaluation of male infertility factors. Decisions for couples with moderate oligoasthenozoospermia (OA) are often empirical because uniform treatment criteria are lacking. This study aimed to evaluate the effect of patients with moderate OA treated with conventional IVF and ICSI. A total of 199 couples with moderate OA undergoing their first IVF/ICSI cycle were included in the study. The patients were divided into two groups according to the type of insemination: conventional IVF group (n = 97) and ICSI group (n = 102). All patients were randomised to be inseminated either by conventional IVF or ICSI. The fertilisation rate, embryo quality, implantation rate and clinical pregnancy rate were examined. No differences in the fertilisation, implantation and pregnancy rates were observed between conventional IVF and ICSI groups (P > 0.05). However, the number of good-quality embryos was significantly higher in the ICSI group than in the IVF group (P < 0.05). Couples with moderate OA did not influence on the overall clinical outcomes between IVF and ICSI treatments, and a negative influence by ICSI on blastocyst development was not confirmed. © 2014 Blackwell Verlag GmbH.
From wastewater to fertilisers--Technical overview and critical review of European legislation governing phosphorus recycling.

PubMed

Hukari, Sirja; Hermann, Ludwig; Nättorp, Anders

2016-01-15

The present paper is based on an analysis of the EU legislation regulating phosphorus recovery and recycling from wastewater stream, in particular as fertiliser. To recover phosphorus, operators need to deal with market regulations, health and environment protection laws. Often, several permits and lengthy authorisation processes for both installation (e.g. environmental impact assessment) and the recovered phosphorus (e.g. End-of-Waste, REACH) are required. Exemptions to certain registration processes for recoverers are in place but rarely applied. National solutions are often needed. Emerging recovery and recycling sectors are affected by legislation in different ways: Wastewater treatment plants are obliged to remove phosphorus but may also recover it in low quantities for operational reasons. Permit processes allowing recovery and recycling operations next to water purification should thus be rationalised. In contrast, the fertiliser industry relies on legal quality requirements, ensuring their market reputation. For start-ups, raw-material sourcing and related legislation will be the key. Phosphorus recycling is governed by fragmented decision-making in regional administrations. Active regulatory support, such as recycling obligation or subsidies, is lacking. Legislation harmonisation, inclusion of recycled phosphorus in existing fertiliser regulations and support of new operators would speed up market penetration of novel technologies, reduce phosphorus losses and safeguard European quality standards.
Space resource utilisation: a novel indicator to quantify species competitive ability for light.

PubMed

Zhang, Pengfei; Zhou, Xiaolong; Li, Junyong; Guo, Zhi; Du, Guozhen

2015-11-23

Species richness and productivity are two fundamental aspects of ecosystems. As a result, the relationship between species richness and productivity has been widely studied. A series of fertilisation experiments in an alpine meadow on the Tibetan Plateau were performed to study the relationship between species richness and productivity. In this paper, we present a novel indicator, i.e., space resource utilisation (SRU), which is calculated by a volume formula (V(i) = h(i) · S(i); h(i) = plant height of species i, S(i) = quadrat area × percent cover of species i). SRU more fully reflected species competitive ability for light in both horizontal and vertical dimensions compared with plant height and cover. We used this novel indicator to investigate the effects of SRU on the changes in species richness and productivity following fertilisation. We found that the SRU of the community was correlated with increasing productivity and decreasing species richness following fertilisation and was a better predictor of species richness than productivity. The changes in SRU following fertilisation vary among species. These results demonstrate that SRU can be a more useful tool in explaining plant biodiversity loss and predicting the fate of different species than each of height, cover and productivity.
Space resource utilisation: a novel indicator to quantify species competitive ability for light

PubMed Central

Zhang, Pengfei; Zhou, Xiaolong; Li, Junyong; Guo, Zhi; Du, Guozhen

2015-01-01

Species richness and productivity are two fundamental aspects of ecosystems. As a result, the relationship between species richness and productivity has been widely studied. A series of fertilisation experiments in an alpine meadow on the Tibetan Plateau were performed to study the relationship between species richness and productivity. In this paper, we present a novel indicator, i.e., space resource utilisation (SRU), which is calculated by a volume formula (Vi = hi · Si; hi = plant height of species i, Si = quadrat area × percent cover of species i). SRU more fully reflected species competitive ability for light in both horizontal and vertical dimensions compared with plant height and cover. We used this novel indicator to investigate the effects of SRU on the changes in species richness and productivity following fertilisation. We found that the SRU of the community was correlated with increasing productivity and decreasing species richness following fertilisation and was a better predictor of species richness than productivity. The changes in SRU following fertilisation vary among species. These results demonstrate that SRU can be a more useful tool in explaining plant biodiversity loss and predicting the fate of different species than each of height, cover and productivity. PMID:26593068
Nucleolar structure and proliferation activity of Arabidopsis root cells from seedlings germinated on the International Space Station

NASA Astrophysics Data System (ADS)

Matía, Isabel; González-Camacho, Fernando; Marco, Roberto; Kiss, John Z.; Gasset, Gilbert; Medina, Francisco-Javier

Seeds of Arabidopsis thaliana were sent to the International Space Station in the "Cervantes Mission" (Spanish Soyuz Mission). Seed germination was initiated in flight by supplying culture medium. Seedlings were grown for 4 days at 22 °C, and growth was stopped by the addition of paraformaldehyde fixative. Once back on the ground, samples were immediately processed for microscopy. A ground control experiment was simultaneously replicated. Glutaraldehyde-fixed root cells from seedlings grown in the Biorack on board of the Space Shuttle (STS-84 Mission) in similar conditions were also ultrastructurally examined. The length of seedlings grown at 1 g was conspicuously shorter than parallel samples grown under microgravity. We examined the morphology of the root meristematic cells, with a focus on their nucleoli in the cortex and stele. In general, root cortical cells proliferate at a higher rate and their nucleoli are more active than those of stele cells. While the stele showed longer cells with larger nucleoli in the flight samples, cortical cells from space-grown seedlings were shorter, more numerous and more densely packed than ground controls. However, nucleoli were smaller and less active in fast proliferating flight cells than in the ground controls. This reduced level of ribosome synthesis in the flight samples is probably the result of an accelerated cell cycle. An altered rate of cell proliferation may be detrimental for the plant and could be the reason for the reported smaller size of older space-grown seedlings. Finally, two-dimensional protein electrophoresis showed noticeable differences between space samples and ground controls.
Small Changes in the Regulation of One Arabidopsis Profilin Isovariant, PRF1, Alter Seedling Development

PubMed Central

McKinney, Elizabeth Cohen; Kandasamy, Muthugapatti K.; Meagher, Richard B.

2001-01-01

Profilin (PRF) is a low-molecular-weight actin binding protein encoded by a diverse gene family in plants. Arabidopsis PRF1 transcripts are moderately well expressed in all vegetative organs. A regulatory mutant in PRF1, prf1-1, was isolated from a library of T-DNA insertions. The insertion disrupted the promoter region of PRF1 100 bp upstream from the transcriptional start site. Although steady state levels of PRF1 transcripts appeared normal in mature prf1-1 plants, the levels in young seedlings were only one-half those observed in wild type. Reactions with a PRF1 isovariant–specific monoclonal antiserum and general anti-profilin antisera demonstrated that PRF1 protein levels also were one-half those found in wild-type seedlings, although total profilin levels were unaffected. Mutant seedlings no longer could downregulate PRF1 levels in the light, as did wild type. Consistent with their molecular phenotypes, young mutant seedlings displayed several morphological phenotypes but developed into apparently normal adult plants. Their initial germination rate and development were slow, and they produced excessive numbers of root hairs. Mutant seedlings had abnormally raised cotyledons, elongated hypocotyls, and elongated cells in the hypocotyl, typical of phenotypes associated with some defects in light and circadian responses. A wild-type PRF1 transgene fully complements the hypocotyl phenotypes in the prf1-1 mutant. The ability of profilin to regulate actin polymerization and participate directly in signal transduction pathways is discussed in light of the prf1-1 phenotypes. PMID:11340190

Seedlings of temperate rainforest conifer and angiosperm trees differ in leaf area display.

PubMed

Lusk, Christopher H; Pérez-Millaqueo, Manuel M; Saldaña, Alfredo; Burns, Bruce R; Laughlin, Daniel C; Falster, Daniel S

2012-07-01

The contemporary relegation of conifers mainly to cold or infertile sites has been ascribed to low competitive ability, as a result of the hydraulic inefficiency of tracheids and their seedlings' initial dependence on small foliage areas. Here it is hypothesized that, in temperate rainforests, the larger leaves of angiosperms also reduce self-shading and thus enable display of larger effective foliage areas than the numerous small leaves of conifers. This hypothesis was tested using 3-D modelling of plant architecture and structural equation modelling to compare self-shading and light interception potential of seedlings of six conifers and 12 angiosperm trees from temperate rainforests. The ratio of displayed leaf area to plant mass (LAR(d)) was used to indicate plant light interception potential: LAR(d) is the product of specific leaf area, leaf mass fraction, self-shading and leaf angle. Angiosperm seedlings self-shaded less than conifers, mainly because of differences in leaf number (more than leaf size), and on average their LAR(d) was about twice that of conifers. Although specific leaf area was the most pervasive influence on LAR(d), differences in self-shading also significantly influenced LAR(d) of large seedlings. The ability to deploy foliage in relatively few, large leaves is advantageous in minimizing self-shading and enhancing seedling light interception potential per unit of plant biomass. This study adds significantly to evidence that vegetative traits may be at least as important as reproductive innovations in explaining the success of angiosperms in productive environments where vegetation is structured by light competition.
Seedlings of temperate rainforest conifer and angiosperm trees differ in leaf area display

PubMed Central

Lusk, Christopher H.; Pérez-Millaqueo, Manuel M.; Saldaña, Alfredo; Burns, Bruce R.; Laughlin, Daniel C.; Falster, Daniel S.

2012-01-01

Background and Aims The contemporary relegation of conifers mainly to cold or infertile sites has been ascribed to low competitive ability, as a result of the hydraulic inefficiency of tracheids and their seedlings' initial dependence on small foliage areas. Here it is hypothesized that, in temperate rainforests, the larger leaves of angiosperms also reduce self-shading and thus enable display of larger effective foliage areas than the numerous small leaves of conifers. Methods This hypothesis was tested using 3-D modelling of plant architecture and structural equation modelling to compare self-shading and light interception potential of seedlings of six conifers and 12 angiosperm trees from temperate rainforests. The ratio of displayed leaf area to plant mass (LARd) was used to indicate plant light interception potential: LARd is the product of specific leaf area, leaf mass fraction, self-shading and leaf angle. Results Angiosperm seedlings self-shaded less than conifers, mainly because of differences in leaf number (more than leaf size), and on average their LARd was about twice that of conifers. Although specific leaf area was the most pervasive influence on LARd, differences in self-shading also significantly influenced LARd of large seedlings. Conclusions The ability to deploy foliage in relatively few, large leaves is advantageous in minimizing self-shading and enhancing seedling light interception potential per unit of plant biomass. This study adds significantly to evidence that vegetative traits may be at least as important as reproductive innovations in explaining the success of angiosperms in productive environments where vegetation is structured by light competition. PMID:22585929
Lead induced changes in growth and micronutrient uptake of Jatropha curcas L.

PubMed

Shu, Xiao; Zhang, QuanFa; Wang, WeiBo

2014-11-01

Effects of lead treatment on growth and micronutrient uptake in Jatropha curcas L. seedlings were assessed by means of microcosm experiments. Results suggested that superoxide dismutase (SOD) activity increased with increasing lead concentration. There was significant positive correlation between lead treatment concentration and SOD and peroxidase activity. Catalase activity was initiated under lower lead stress but, was inhibited under higher lead exposure. Lead had a stimulating effect on seedlings height and leaf area at lower lead concentrations. The J. curcas can accumulate higher amounts of available lead from soil but can translocate only low amounts to the shoots. Results indicating SOD and peroxidase activity in J. curcas seedlings played an important role in resisting the oxidative stress induced by lead. The addition of lead significantly increased the content of zinc in plant tissue and enhanced the transport of iron from roots to shoots but contributed to a decrease in measured copper, iron, and manganese content.
Elimination of toxicity from polyurethane foam plugs used for plant culture

NASA Technical Reports Server (NTRS)

Wheeler, R. M.; Schwartzkopf, S. H.; Tibbitts, T. W.; Langhans, R. W.

1985-01-01

Polyurethane foam plugs commonly are used as collars or supports to grow plants in solution culture. Despite their utility, these foam plugs can be quite toxic to plants, particularly to small seedlings. We have observed tissue injury in tests using plugs to support lettuce, red beet, and potato plants in solution culture. Typically, the injury is initiated on the hypocotyl or stem tissue in direct contact with the foam, and appears within 30 hr as a brownish discoloration on the tissue surface. This discoloration can be followed by complete collapse of affected tissue and eventual death of the seedling. When injury does not progress beyond surface browning, the seedling survives but growth is slowed. In this paper, we report on different treatments that can be used to remove the toxicity of these plugs so they can be used in plant research.
Juno is the egg Izumo receptor and is essential for mammalian fertilisation

PubMed Central

Bianchi, Enrica; Doe, Brendan; Goulding, David; Wright, Gavin J.

2014-01-01

Fertilisation occurs when sperm and egg recognise each other and fuse to form a new, genetically distinct organism. The molecular basis of sperm-egg recognition is unknown, but is likely to require interactions between receptor proteins displayed on their surface. Izumo1 is an essential sperm cell surface protein, but its egg receptor has remained a mystery. Here, we identify Juno as the receptor for Izumo1 on mouse eggs, and show this interaction is conserved within mammals. Female mice lacking Juno are infertile and Juno-deficient eggs do not fuse with normal sperm. Rapid shedding of Juno from the oolemma after fertilisation suggests a mechanism for the membrane block to polyspermy, ensuring eggs normally fuse with just a single sperm. Our discovery of an essential receptor pair at the nexus of conception provides opportunities for the rational development of new fertility treatments and contraceptives. PMID:24739963
Sperm proteins in teleostean and chondrostean (sturgeon) fishes.

PubMed

Li, Ping; Hulak, Martin; Linhart, Otomar

2009-11-01

Sperm proteins in the seminal plasma and spermatozoa of teleostean and chondrostean have evolved adaptations due to the changes in the reproductive environment. Analysis of the composition and functions of these proteins provides new insights into sperm motility and fertilising abilities, thereby creating possibilities for improving artificial reproduction and germplasm resource conservation technologies (e.g. cryopreservation). Seminal plasma proteins are involved in the protection of spermatozoa during storage in the reproductive system, whereas all spermatozoa proteins contribute to the swimming and fertilising abilities of sperm. Compared to mammalian species, little data are available on fish sperm proteins and their functions. We review here the current state of the art in this field and focus on relevant subjects that require attention. Future research should concentrate on protein functions and their mode of action in fish species, especially on the role of spermatozoa surface proteins during fertilisation and on a description of sturgeon sperm proteins.
Loss of desiccation tolerance in Copaifera langsdorffii Desf. seeds during germination.

PubMed

Pereira, W V S; Faria, J M R; Tonetti, O A O; Silva, E A A

2014-05-01

This study evaluated the loss of desiccation tolerance in C. langsdorffii seeds during the germination process. Seeds were imbibed for 24, 48, 72, 96, 120 and 144 hours and dried to the initial moisture content, kept in this state for 3 days after which they were submitted to pre-humidification and rehydration. Ultraestructural evaluations were done aiming to observe the cell damage caused by the dry process. Desiccation tolerance was evaluated in terms of the percentage of normal seedlings. Seeds not submitted to the drying process presented 61% of normal seedlings, and after 24 hours of imbibition, followed by drying, the seeds presented the same percentage of survival. However, after 48 hours of imbibition, seeds started to lose the desiccation tolerance. There was twenty six percent of normal seedlings formed from seeds imbibed for 96 hours and later dried and rehydrated. Only 5% of seeds imbibed for 144 hours, dried and rehydrated formed normal seedlings. At 144 hours of imbibition followed the dry process, there was damage into the cell structure, indicating that the seeds were unable to keep the cell structure during the drying process. Copaifera langsdorffii seeds loses the desiccation tolerance at the start of Phase 2 of imbibition.
Ontogenetic patterns of CO sub 2 exchange of Quercus rubra L. leaves during three flushes of shoot growth I. median flush leaves

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hanson, P.J.; Isebrands, J.G.; Dickson, R.E.

1988-03-01

Oak (Quercus) seedlings exhibit a pattern of shoot growth known to place demands on carbohydrate and nutrient reserves. This study was designed to determine ontogenetic patterns in CO{sub 2} exchanges properties of red oak leaves, and to determine if individual leaf CO{sub 2} exchange rates (CER) increase in response to the assimilate demand placed on a seedling during flushing. Northern red oak (Q. rubra L.) seedlings were grown in environments favorable for multiple flushes of shoot growth. Measurements of CER on single, attached, median leaves from each flush were made over a range of photosynthetic photon flux densities on plantsmore » at nine stages of seedling development through three flushes of growth. Carbon dioxide exchange rate of red oak leaves increased during leaf development up to and beyond full leaf expansion before decreasing an unusual pattern of photosynthesis during leaf ontogeny. Furthermore, first- and second-flush leaf CER initially decreased and then increased in conjunction with the third flush of shoot growth. These patterns indicate that red oak leaves have a capacity for CER adjustment in response to increase sink demand.« less
Precommercial thinning intensity in longleaf pine: effect on product volume and value

Treesearch

John S. Kush; William D. Boyer; Ralph S. Meldahl; George A. Ward

1998-01-01

The possible benefit of precommercial thinning in longleaf pine was evaluated from a spacing study initiated in 1967 on the Escambia Experimental Forest in Brewton, AL. The study was established in dense, naturally established, seedling stands 9 years from seed. Plots were thinned to densities of 300, 600, 900, 1200, and 1500 trees/acre. Later, the initial range of...
Using common mycorrhizal networks for controlled inoculation of Quercus spp. with Tuber melanosporum: the nurse plant method.

PubMed

Pereira, Guillermo; Palfner, Götz; Chávez, Daniel; Suz, Laura M; Machuca, Angela; Honrubia, Mario

2013-07-01

The high cost and restricted availability of black truffle spore inoculum for controlled mycorrhiza formation of host trees produced for truffle orchards worldwide encourage the search for more efficient and sustainable inoculation methods that can be applied globally. In this study, we evaluated the potential of the nurse plant method for the controlled inoculation of Quercus cerris and Quercus robur with Tuber melanosporum by mycorrhizal networks in pot cultures. Pine bark compost, adjusted to pH 7.8 by liming, was used as substrate for all assays. Initially, Q. robur seedlings were inoculated with truffle spores and cultured for 12 months. After this period, the plants presenting 74 % mycorrhizal fine roots were transferred to larger containers. Nurse plants were used for two treatments of two different nursling species: five sterilized acorns or five 45-day-old, axenically grown Q. robur or Q. cerris seedlings, planted in containers around the nurse plant. After 6 months, colonized nursling plant root tips showed that mycorrhiza formation by T. melanosporum was higher than 45 % in the seedlings tested, with the most successful nursling combination being Q. cerris seedlings, reaching 81 % colonization. Bulk identification of T. melanosporum mycorrhizae was based on morphological and anatomical features and confirmed by sequencing of the internal transcribed spacer region of the ribosomal DNA of selected root tips. Our results show that the nurse plant method yields attractive rates of mycorrhiza formation by the Périgord black truffle and suggest that establishing and maintaining common mycorrhizal networks in pot cultures enables sustained use of the initial spore inoculum.
Following isotopes in pulse-chase enriched aspen seedlings

NASA Astrophysics Data System (ADS)

Norris, C. E.; Wasylishen, R. E.; Landhäusser, S.; Quideau, S. A.

2011-12-01

One method to quantitatively trace biogeochemical fluxes through ecosystems, such as organic matter decomposition, is to use plant material enriched with stable isotopes. However, as plant macromolecules are known to vary in their rate of formation and decomposition, both the enrichment levels and the location of enrichment within the plant material should be characterized prior to decomposition and tracing studies. Aspen (Populus tremuloides Michx.) is a common tree species with a diverse organic matter chemical structure found in the western Canadian boreal forest. This study used a multi pulse and multi chase enrichment of stable isotopes (15N and 13C) on aspen seedlings to determine the seedling enrichment, isotope movement among plant tissues and translocation of isotopes within plant macromolecules e.g., carbohydrates and lignin. As expected, all tissues experienced increased enrichment with multiple pulses. An initial enrichment with 13C was observed in the leaves followed by translocation to the stems and roots while the 15N moved upward from the roots to leaves. The macromolecular chemistry of the organic carbon was further characterized using 13C solid state nuclear magnetic resonance spectroscopy. After the initial two hour chase period enrichment of the O-alkyl type (carbohydrate) carbon within the leaves was identified, followed by redistribution to more complex carbon compounds after the one week chase period. Root and stem tissues did not show the same pattern. Rather, changes in 13C enrichment were observed in shifting ethyl and methyl alkyl (lipid) carbon peak intensities for the stem samples while roots did not preferentially allocate 13C to a specific macromolecule. These results confirm that stable isotope enrichment of plants was non-uniform across macromolecules and tissue types. Enrichment of aspen seedlings was therefore dependant on the pulse-chase sequence used.
Novel plant communities limit the effects of a managed flood to restore riparian forests along a large regulated river

USGS Publications Warehouse

Cooper, D.J.; Andersen, D.C.

2012-01-01

Dam releases used to create downstream flows that mimic historic floods in timing, peak magnitude and recession rate are touted as key tools for restoring riparian vegetation on large regulated rivers. We analysed a flood on the 5th-order Green River below Flaming Gorge Dam, Colorado, in a broad alluvial valley where Fremont cottonwood riparian forests have senesced and little recruitment has occurred since dam completion in 1962. The stable post dam flow regime triggered the development of novel riparian communities with dense herbaceous plant cover. We monitored cottonwood recruitment on landforms inundated by a managed flood equal in magnitude and timing to the average pre-dam flood. To understand the potential for using managed floods as a riparian restoration tool, we implemented a controlled and replicated experiment to test the effects of artificially modified ground layer vegetation on cottonwood seedling establishment. Treatments to remove herbaceous vegetation and create bare ground included herbicide application (H), ploughing (P), and herbicide plus ploughing (H+P). Treatment improved seedling establishment. Initial seedling densities on treated areas were as much as 1200% higher than on neighbouring control (C) areas, but varied over three orders of magnitude among the five locations where manipulations were replicated. Only two replicates showed the expected seedling density rank of (H+P)>P>H>C. Few seedlings established in control plots and none survived 1 year. Seedling density was strongly affected by seed rain density. Herbivory affected growth and survivorship of recruits, and few survived nine growing seasons. Our results suggest that the novel plant communities are ecologically and geomorphically resistant to change. Managed flooding alone, using flows equal to the pre-dam mean annual peak flood, is an ineffective riparian restoration tool where such ecosystem states are present and floods cannot create new habitat for seedling establishment. This problem significantly limits long-term river and riparian management options. ?? 2010 John Wiley & Sons, Ltd.
Uptake and translocation of phytochemical 2-benzoxazolinone (BOA) in radish seeds and seedlings.

PubMed

Chiapusio, Geneviève; Pellissier, François; Gallet, Christiane

2004-07-01

The molecular aspects of phytochemical interactions between plants, especially the process of phytochemical translocation by the target plant, remain challenging for those studying allelopathy. 2-Benzoxazolinone (BOA) is a natural chemical produced by rye (Secale cereale) and is known to have phytotoxic effects on weed seeds and seedlings. The translocation of BOA into target plants has been poorly investigated. Therefore, the total absorption of [ring U 14C] BOA was estimated by oxidizing whole seedlings of Raphanus sativus cv. for 8 days and quantifying the radioactivity. Non-radiolabelled BOA in seedlings was also estimated by HPLC. BOA applied at 10(-3) M was readily taken up by germinated radish at a rate of 1556 nmol g(-1) FW. At these same concentrations, BOA reduced radish germination by 50% and caused a delay in radicle elongation. Exogenous BOA was responsible for the observed germination inhibition. At a concentration of 10(-5) M, BOA was taken up by germinated seeds (31 nmol g(-1) FW), but this quantity did not affect radish germination. Labelled BOA was not mineralized in the culture medium during seedling growth as no 14CO2 was recovered. Both 10(-3) and 10(-5) M BOA were translocated into radish organs, mainly into roots and cotyledons. These organs were then identified as potential physiological target sites. Cotyledons remained the target sink (44% of the total radioactivity). The kinetics of BOA uptake at 10(-3) and 10(-5) M in radish seedlings was identical: BOA accumulation was proportional to its initial concentration. A comparison between radioactivity and HPLC quantification for 10(-3) M BOA indicated that BOA (along with some metabolites) could effectively be recovered in radish organs using chromatography.
Acclimation responses to high light by Guazuma ulmifolia Lam. (Malvaceae) leaves at different stages of development.

PubMed

Calzavara, A K; Rocha, J S; Lourenço, G; Sanada, K; Medri, C; Bianchini, E; Pimenta, J A; Stolf-Moreira, R; Oliveira, H C

2017-09-01

The re-composition of deforested environments requires the prior acclimation of seedlings to full sun in nurseries. Seedlings can overcome excess light either through the acclimation of pre-existing fully expanded leaves or through the development of new leaves that are acclimated to the new light environment. Here, we compared the acclimation capacity of mature (MatL, fully expanded at the time of transfer) and newly expanded (NewL, expanded after the light shift) leaves of Guazuma ulmifolia Lam. (Malvaceae) seedlings to high light. The seedlings were initially grown under shade and then transferred to full sunlight. MatL and NewL were used for chlorophyll fluorescence and gas exchange analyses, pigment extraction and morpho-anatomical measurements. After the transfer of seedlings to full sun, the MatL persisted and acclimated to some extent to the new light condition, since they underwent alterations in some morpho-physiological traits and maintained a functional electron transport chain and positive net photosynthesis rate. However, long-term exposure to high light led to chronic photoinhibition in MatL, which could be related to the limited plasticity of leaf morpho-anatomical attributes. However, the NewL showed a high capacity to use the absorbed energy in photochemistry and dissipate excess energy harmlessly, attributes that were favoured by the high structural plasticity exhibited by these leaves. Both the maintenance of mature, photosynthetically active leaves and the production of new leaves with a high capacity to cope with excess energy were important for acclimation of G. ulmifolia seedlings. © 2017 German Botanical Society and The Royal Botanical Society of the Netherlands.
The future of the Human Fertilisation and Embryology Authority.

PubMed

English, Veronica

2013-04-01

The UK Government has proposed that the Human Fertilisation and Embryology Authority (HFEA) should be abolished and its functions transferred to the Care Quality Commission. This commentary explores the problems with this proposal and suggests that an independent review of how the HFEA carries out its functions and a subsequent reform of some of its practices represent a better option for the UK. Copyright © 2013 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.
Effect of nutrient-based fertilisers of olive trees on olive oil quality.

PubMed

Tekaya, Meriem; Mechri, Beligh; Bchir, Amani; Attia, Faouzi; Cheheb, Hechmi; Daassa, Mohamed; Hammami, Mohamed

2013-06-01

This work was conducted to determine the effects of two nutrient-based fertilisers on the general physicochemical characteristics (including free fatty acid content, peroxide value and UV spectrophotometric characteristics), fatty acid profile, total phenols, o-diphenols and phytosterol composition of olive oil. Foliar applications were carried out in two successive years and included four treatments: TC (control, without foliar nutrition), T1 (rich in nitrogen, applied at the start of vegetation, 10 days later and 20 days later), T2 (rich in boron, magnesium, sulfur and manganese, applied at the beginning of flowering and 10 days later) and T3 (T1+T2). At the end of the experiment (after 2 years), oils were extracted and analysed. No effect was found on either general physicochemical characteristics or fatty acid composition. Foliar fertilisation caused a significant decrease in both polyphenol and o-diphenol contents. Total sterol content was unaffected by foliar fertilisation. However, the phytosterol composition of the oil, particularly its β-sitosterol level, was markedly improved after foliar nutrient application. Principal component analysis of the phytosterol composition showed discrimination between the control oil and the oils from T1, T2 and T3 treatments. The results of this study extend the current knowledge of such cross-talk between plant nutrition and quality of oil. © 2012 Society of Chemical Industry.
Sperm competition dynamics: ejaculate fertilising efficiency changes differentially with time.

PubMed

Pizzari, Tommaso; Worley, Kirsty; Burke, Terry; Froman, David P

2008-12-16

A fundamental challenge in evolutionary biology is to resolve the mechanisms that maintain paternity a hypervariable fitness component. Because females are often sexually promiscuous, this challenge hinges on establishing the mechanisms through which the ejaculates of different males compete for fertilisation (sperm competition). The competitive quality of an ejaculate is mediated by the relative number of live sperm and their motile performance. The differential rate at which rival ejaculates lose their fertilising efficiency over time is therefore expected to influence the outcome of sperm competition. Here, we artificially inseminated into sets of replicate domestic hens, Gallus gallus domesticus, experimentally engineered heterospermic ejaculates containing a large number of low-quality sperm from one male, and a lower number of high-quality sperm from another male. Large, low-quality ejaculates fertilised the first eggs produced after insemination, but small, high-quality ejaculates prevailed in the long run despite their numerical disadvantage. Together, these results provide the first experimental demonstration that the relative competitive value of an ejaculate changes drastically over the time during which competing ejaculates are stored within the reproductive tract of a female, resulting in a marked temporal pattern of variation in paternity. A high level of replication makes these results robust. However, our study was restricted to few males of a well characterised study population, and future work should explore the generality of these results.
Dynamics of sperm subpopulations based on motility and plasma membrane status in thawed ram spermatozoa incubated under conditions that support in vitro capacitation and fertilisation.

PubMed

García-Álvarez, Olga; Maroto-Morales, Alejandro; Ramón, Manuel; del Olmo, Enrique; Jiménez-Rabadán, Pilar; Fernández-Santos, M Rocio; Anel-López, Luis; Garde, J Julián; Soler, Ana J

2014-06-01

The present study evaluated modifications occurring in thawed ram spermatozoa during incubation in different media that supported in vitro capacitation and fertilisation, and examines how these changes relate to IVF. Thawed sperm samples were incubated under capacitating (Cap) and non-capacitating (non-Cap) conditions for 0, 1 and 2h and used in an IVF test. During incubation, changes related to membrane status and the motility pattern of spermatozoa were assessed, the latter being used to characterise sperm subpopulations. A significantly greater increase (P≤0.05) in the percentage of spermatozoa with higher membrane fluidity was observed in samples incubated with Cap medium from the beginning of incubation. In addition, changes over time in the distribution of the motile subpopulation were particularly evident when spermatozoa were incubated with Cap medium, with a noted increase in spermatozoa classified as 'hyperactivated like', with major changes occurring after 1h incubation. Both characteristics (i.e. membrane fluidity and the percentage of the hyperactivated-like subpopulation) were significantly related with in vitro fertility, and only sperm samples incubated with the Cap medium were capable of fertilising oocytes. These results support the idea that changes in sperm membrane fluidity and motility pattern (i.e. an increase in hyperactivated spermatozoa) are needed for fertilisation to take place.
Sperm competition dynamics: ejaculate fertilising efficiency changes differentially with time

PubMed Central

2008-01-01

Background A fundamental challenge in evolutionary biology is to resolve the mechanisms that maintain paternity a hypervariable fitness component. Because females are often sexually promiscuous, this challenge hinges on establishing the mechanisms through which the ejaculates of different males compete for fertilisation (sperm competition). The competitive quality of an ejaculate is mediated by the relative number of live sperm and their motile performance. The differential rate at which rival ejaculates lose their fertilising efficiency over time is therefore expected to influence the outcome of sperm competition. Results Here, we artificially inseminated into sets of replicate domestic hens, Gallus gallus domesticus, experimentally engineered heterospermic ejaculates containing a large number of low-quality sperm from one male, and a lower number of high-quality sperm from another male. Large, low-quality ejaculates fertilised the first eggs produced after insemination, but small, high-quality ejaculates prevailed in the long run despite their numerical disadvantage. Conclusion Together, these results provide the first experimental demonstration that the relative competitive value of an ejaculate changes drastically over the time during which competing ejaculates are stored within the reproductive tract of a female, resulting in a marked temporal pattern of variation in paternity. A high level of replication makes these results robust. However, our study was restricted to few males of a well characterised study population, and future work should explore the generality of these results. PMID:19087292
Ethical opinions and personal attitudes of young adults conceived by in vitro fertilisation.

PubMed

Siegel, S; Dittrich, R; Vollmann, J

2008-04-01

Today in vitro fertilisation (IVF) is a widespread and important technique of reproductive medicine. When the technique was first used, it was considered ethically controversial. This is the first study conducted of adult IVF-offspring in order to learn about their ethical opinions and personal attitudes towards this medical technology. We recruited the participants from the first cases of in vitro fertilisation in Germany at the Gynaecological Clinic of the University Hospital Erlangen. Our qualitative interview study consisted of in-depth, face-to-face interviews with 16 adults who had been conceived by IVF. Our data was analysed with methods of Grounded Theory. For these adults, the most important factor influencing their personal attitudes towards IVF was the knowledge that they were deeply wanted children. The artificiality of their conception seemed irrelevant for their ethical opinion. All participants mentioned that it was important for them to be informed about the circumstances of their conception by their parents. IVF seems to be a medical technique which, although it affects intimate aspects of human existence, can be integrated into the lives of the affected persons without any great difficulties. The findings suggest that parents should inform their children about their fertilisation at an early age and as part of a process over time, not only on a single occasion. Physicians should advise IVF-parents accordingly.

Novel Applications for Oxalate-Phosphate-Amine Metal-Organic-Frameworks (OPA-MOFs): Can an Iron-Based OPA-MOF Be Used as Slow-Release Fertilizer?

PubMed Central

Anstoetz, Manuela; Rose, Terry J.; Clark, Malcolm W.; Yee, Lachlan H.; Raymond, Carolyn A.; Vancov, Tony

2015-01-01

A porous iron-based oxalate-phosphate-amine metal-organic framework material (OPA-MOF) was investigated as a microbially-induced slow-release nitrogen (N) and phosphorus (P) fertilizer. Seedling growth, grain yields, nutrient uptake of wheat plants, and soil dynamics in incubated soil, were investigated using OPA-MOF vs standard P (triple-superphosphate) and N (urea) fertilizers in an acidic Ferralsol at two application rates (equivalent 120 and 40 kg N ha-1). While urea hydrolysis in the OPA-MOF treatment was rapid, conversion of ammonium to nitrate was significantly inhibited compared to urea treatment. Reduced wheat growth in OPA-MOF treatments was not caused by N-deficiency, but by limited P-bioavailability. Two likely reasons were slow P-mobilisation from the OPA-MOF or rapid P-binding in the acid soil. P-uptake and yield in OPA-MOF treatments were significantly higher than in nil-P controls, but significantly lower than in conventionally-fertilised plants. OPA-MOF showed potential as enhanced efficiency N fertilizer. However, as P-bioavailability was insufficient to meet plant demands, further work should determine if P-availability may be enhanced in alkaline soils, or whether central ions other than Fe, forming the inorganic metal-P framework in the MOF, may act as a more effective P-source in acid soils. PMID:26633174
Effect of specific plant-growth-promoting rhizobacteria (PGPR) on growth and uptake of neonicotinoid insecticide thiamethoxam in corn (Zea mays L.) seedlings.

PubMed

Myresiotis, Charalampos K; Vryzas, Zisis; Papadopoulou-Mourkidou, Euphemia

2015-09-01

Corn (Zea mays L.) is one of the most important cereal crops in the world and is used for food, feed and energy. Inoculation with plant-growth-promoting rhizobacteria (PGPR) would reduce the use of chemical fertilisers and pesticides and could be suggested as an alternative practice for sustainable production of corn in modern agricultural systems. In this study, the effect of two Bacillus PGPR formulated products, Companion (B. subtilis GB03) and FZB24 (B. subtilis FZB24), on corn growth and root uptake of insecticide thiamethoxam was investigated. All bacterial treatments enhanced root biomass production by 38-65% compared with the uninoculated control, with no stimulatory effect of PGPR on above-ground biomass of corn. The uptake results revealed that, in plants inoculated with the PGPR B. subtilis FZB24 and B. subtilis GB03, singly or in combination, the uptake and/or systemic translocation of thiamethoxam in the above-ground corn parts was significantly higher at the different growth ages compared with the control receiving no bacterial treatment. The findings suggest that the PGPR-elicited enhanced uptake of thiamethoxam could lead to improved efficiency of thiamethoxam using reduced rates of pesticides in combination with PGPR as an alternative crop protection technique. © 2014 Society of Chemical Industry.
Novel Applications for Oxalate-Phosphate-Amine Metal-Organic-Frameworks (OPA-MOFs): Can an Iron-Based OPA-MOF Be Used as Slow-Release Fertilizer?

PubMed

Anstoetz, Manuela; Rose, Terry J; Clark, Malcolm W; Yee, Lachlan H; Raymond, Carolyn A; Vancov, Tony

2015-01-01

A porous iron-based oxalate-phosphate-amine metal-organic framework material (OPA-MOF) was investigated as a microbially-induced slow-release nitrogen (N) and phosphorus (P) fertilizer. Seedling growth, grain yields, nutrient uptake of wheat plants, and soil dynamics in incubated soil, were investigated using OPA-MOF vs standard P (triple-superphosphate) and N (urea) fertilizers in an acidic Ferralsol at two application rates (equivalent 120 and 40 kg N ha(-1)). While urea hydrolysis in the OPA-MOF treatment was rapid, conversion of ammonium to nitrate was significantly inhibited compared to urea treatment. Reduced wheat growth in OPA-MOF treatments was not caused by N-deficiency, but by limited P-bioavailability. Two likely reasons were slow P-mobilisation from the OPA-MOF or rapid P-binding in the acid soil. P-uptake and yield in OPA-MOF treatments were significantly higher than in nil-P controls, but significantly lower than in conventionally-fertilised plants. OPA-MOF showed potential as enhanced efficiency N fertilizer. However, as P-bioavailability was insufficient to meet plant demands, further work should determine if P-availability may be enhanced in alkaline soils, or whether central ions other than Fe, forming the inorganic metal-P framework in the MOF, may act as a more effective P-source in acid soils.
Effect of osmopriming on germination and initial growth of Physalis angulata L. under salt stress and on expression of associated genes.

PubMed

Souza, Manuela O DE; Pelacani, Claudinéia R; Willems, Leo A J; Castro, Renato D DE; Hilhorst, Henk W M; Ligterink, Wilco

2016-01-01

This study aimed to evaluate the effects of priming on seed germination under salt stress and gene expression in seeds and seedlings of P. angulata L. After priming for 10 days, seed germination was tested in plastic trays containing 15 ml of water (0 dS m-1 - control) or 15 ml of NaCl solution (2, 4, 6, 8, 10, 12, 14 and 16 dS m-1). Fresh and dry weight of shoots and roots of seedlings were evaluated at 0, 2, 4, 6, 8 dS m-1. Total RNA was extracted from whole seeds and seedlings followed by RT-qPCR. The target genes selected for this study were: ascorbate peroxidase (APX), glutathione-S-transferase (GST), thioredoxin (TXN), high affinity potassium transporter protein 1 (HAK1) and salt overly sensitive 1 (SOS1). At an electroconductivity of 14 dS m-1 the primed seeds still germinated to 72%, in contrast with the non-primed seeds which did not germinate. The relative expression of APX was higher in primed seeds and this may have contributed to the maintenance of high germination in primed seeds at high salt concentrations. GST and TXN displayed increased transcript levels in shoots and roots of seedlings from primed seeds. Priming improved seed germination as well as salt tolerance and this is correlated with increased expression of APX in seeds and SOS1, GST and TXN in seedlings.
N use efficiencies and N2O emissions in two contrasting, biochar amended soils under winter wheat—cover crop—sorghum rotation

NASA Astrophysics Data System (ADS)

Hüppi, Roman; Neftel, Albrecht; Lehmann, Moritz F.; Krauss, Maike; Six, Johan; Leifeld, Jens

2016-08-01

Biochar, a carbon-rich, porous pyrolysis product of organic residues, is evaluated as an option to tackle major problems of the global food system. Applied to soil, biochar can sequester carbon and have beneficial effects on nitrogen (N) cycling, thereby enhancing crop yields and reducing nitrous oxide (N2O) emissions. There is little understanding of the underlying mechanisms, but many experiments indicated increased yields and manifold changes in N transformation, suggesting an increase in N use efficiency. Biochar’s effects can be positive in extensively managed tropical agriculture, however less is known about its use in temperate soils with intensive fertilisation. We tested the effect of slow pyrolysis wood chip biochar on N use efficiency, crop yields and N2O emissions in a lysimeter system with two soil types (sandy loamy Cambisol and silty loamy Luvisol) in a winter wheat—cover crop—sorghum rotation. 15N-labelled ammonium nitrate fertiliser (170 kg N ha-1 in 3 doses, 10% 15N) was applied to the first crop to monitor its fate in three ecosystem components (plants, soil, leachate). Green rye was sown as cover crop to keep the first year’s fertiliser N for the second year’s sorghum crop (fertilised with 110 kg N ha-1 in two doses and natural abundance 15N). We observed no effects of biochar on N fertiliser use efficiency, yield or N uptake for any crop. Biochar reduced leaching by 43 ± 19% but only towards the end of the experiment with leaching losses being generally low. For both soils N2O emissions were reduced by 15 ± 4% with biochar compared to the control treatments. Our results indicate that application of the chosen biochar induces environmental benefits in terms of N2O emission and N leaching but does not substantially affect the overall N cycle and hence crop performance in the analyzed temperate crop rotation.
Delayed prescribed burning in a seedling and sapling Longleaf Pine plantation in Louisiana

Treesearch

James D. Haywood

2002-01-01

To examine the effects of delaying prescribed burning for several years, I initiated five treatments in a 5- to 6-year-old longleaf pine stand: a check of no control; biennial hardwood control by directed chemical application; and biennial burning in either early March, May, or July. After the initial burns, longleaf pine survival decreased from 82 percent in February...
Utilizing ARC EMCS Seedling Cassettes as Highly Versatile Miniature Growth Chambers for Model Organism Experiments

NASA Technical Reports Server (NTRS)

Freeman, John L.; Steele, Marianne K.; Sun, Gwo-Shing; Heathcote, David; Reinsch, S.; DeSimone, Julia C.; Myers, Zachary A.

2014-01-01

The aim of our ground testing was to demonstrate the capability of safely putting specific model organisms into dehydrated stasis, and to later rehydrate and successfully grow them inside flight proven ARC EMCS seedling cassettes. The ARC EMCS seedling cassettes were originally developed to support seedling growth during space flight. The seeds are attached to a solid substrate, launched dry, and then rehydrated in a small volume of media on orbit to initiate the experiment. We hypothesized that the same seedling cassettes should be capable of acting as culture chambers for a wide range of organisms with minimal or no modification. The ability to safely preserve live organisms in a dehydrated state allows for on orbit experiments to be conducted at the best time for crew operations and more importantly provides a tightly controlled physiologically relevant growth experiment with specific environmental parameters. Thus, we performed a series of ground tests that involved growing the organisms, preparing them for dehydration on gridded Polyether Sulfone (PES) membranes, dry storage at ambient temperatures for varying periods of time, followed by rehydration. Inside the culture cassettes, the PES membranes were mounted above blotters containing dehydrated growth media. These were mounted on stainless steel bases and sealed with plastic covers that have permeable membrane covered ports for gas exchange. The results showed we were able to demonstrate acceptable normal growth of C.elegans (nematodes), E.coli (bacteria), S.cerevisiae (yeast), Polytrichum (moss) spores and protonemata, C.thalictroides (fern), D.discoideum (amoeba), and H.dujardini (tardigrades). All organisms showed acceptable growth and rehydration in both petri dishes and culture cassettes initially, and after various time lengths of dehydration. At the end of on orbit ISS European Modular Cultivation System experiments the cassettes could be frozen at ultra-low temperatures, refrigerated, or chemically preserved before being returned to Earth for analyses. Our results suggest that with protocol modifications and future verification testing we can utilize the versatile EMCS to conduct tightly controlled experiments inside our culture cassettes for a wide variety of organisms. These physiological experiments would be designed to answer questions at the molecular level about the specific stress responses of space flight.
Identification of new members of Fertilisation Independent Seed Polycomb Group pathway involved in the control of seed development in Arabidopsis thaliana.

PubMed

Guitton, Anne-Elisabeth; Page, Damian R; Chambrier, Pierre; Lionnet, Claire; Faure, Jean-Emmanuel; Grossniklaus, Ueli; Berger, Frédéric

2004-06-01

In higher plants, double fertilisation initiates seed development. One sperm cell fuses with the egg cell and gives rise to the embryo, the second sperm cell fuses with the central cell and gives rise to the endosperm. The endosperm develops as a syncytium with the gradual organisation of domains along an anteroposterior axis defined by the position of the embryo at the anterior pole and by the attachment to the placenta at the posterior pole. We report that ontogenesis of the posterior pole in Arabidopsis thaliana involves oriented migration of nuclei in the syncytium. We show that this migration is impaired in mutants of the three founding members of the FERTILIZATION INDEPENDENT SEED (FIS) class, MEDEA (MEA), FIS2 and FERTILIZATION INDEPENDENT ENDOSPERM (FIE). A screen based on a green fluorescent protein (GFP) reporter line allowed us to identify two new loci in the FIS pathway, medicis and borgia. We have cloned the MEDICIS gene and show that it encodes the Arabidopsis homologue of the yeast WD40 domain protein MULTICOPY SUPRESSOR OF IRA (MSI1). The mutations at the new fis loci cause the same cellular defects in endosperm development as other fis mutations, including parthenogenetic development, absence of cellularisation, ectopic development of posterior structures and overexpression of the GFP marker.
Response to: Yazdani A. Surgery or in vitro fertilisation: The simplicity of this question belies its complexity. When all you have is a hammer, everything looks like a nail.

PubMed

Abbott, Jason

2018-02-01

This is perhaps the most apt mantra of IVF (in vitro fertilisation) as a treatment in Australasia in this day and age. It is also important to note the truth in the identification of IVF being low skill-based, largely independent of the practitioner, but more importantly costly, and with few exceptions, only available in the private sector. Such revelations really require a rethink of the entire reproductive endocrinology and infertility (CREI) subspecialty. In fact, if there is only one solution to all fertility problems - that of the 'effective IVF procedure' - why not do away completely with the clinician and simply have nurse practitioners who oversee the identified issue of an individual or couple wanting a pregnancy? This in conjunction with the outstanding scientific advances that led to the initiation and promulgation of IVF really would reduce costs by cutting out the unnecessary clinician middle-person who is unimportant in the equation. It may be that such cost reduction, the disbandment of the irrelevant subspecialty and protocol-driven, high-quality fertility checklists would allow this to be a publically accessible service for all, not just those who can afford it. © 2018 The Royal Australian and New Zealand College of Obstetricians and Gynaecologists.
Germination and allometry of the native palm tree Euterpe edulis compared to the introduced E. oleracea and their hybrids in Atlantic rainforest.

PubMed

Tiberio, F C S; Sampaio-e-Silva, T A; Dodonov, P; Garcia, V A; Silva Matos, D M

2012-11-01

Palms are distinctive plants of tropics and have peculiar allometric relations. Understanding such relations is useful in the case of introduced species because their ability to establish and invade must be clarified in terms of their responses in the new site. Our purpose was to assess the survival and invasive capacity of an introduced palm species in the Atlantic rainforest, Euterpe oleracea Mart., compared to the native Euterpe edulis Mart. and to the hybrids produced between the two species. Considering this, we compared the allometry in different ontogenetic stages, the germination rates, and aspects of the initial development. The ontogenetic stages proposed for both Euterpe illustrated the growth patterns described for palm trees. E. oleracea and hybrids adjusted to the geometric similarity allometric model, while E. edulis presented a slope greater than would be expected considering this model, indicating a greater height for a given diameter. E. oleracea showed the same amount of pulp per fruit as E. edulis and a similar initial development of seedlings. The main differences observed were a lower germination rate and a faster height gain of E. oleracea seedlings. We conclude that E. oleracea, which is similar to E. edulis in aspects of allometry, development, seed and seedling morphology, may be an important competitor of this native palm tree in the Atlantic Forest.
Distinct Calcium Signaling Pathways Regulate Calmodulin Gene Expression in Tobacco1

PubMed Central

van der Luit, Arnold H.; Olivari, Claudio; Haley, Ann; Knight, Marc R.; Trewavas, Anthony J.

1999-01-01

Cold shock and wind stimuli initiate Ca2+ transients in transgenic tobacco (Nicotiana plumbaginifolia) seedlings (named MAQ 2.4) containing cytoplasmic aequorin. To investigate whether these stimuli initiate Ca2+ pathways that are spatially distinct, stress-induced nuclear and cytoplasmic Ca2+ transients and the expression of a stress-induced calmodulin gene were compared. Tobacco seedlings were transformed with a construct that encodes a fusion protein between nucleoplasmin (a major oocyte nuclear protein) and aequorin. Immunocytochemical evidence indicated targeting of the fusion protein to the nucleus in these plants, which were named MAQ 7.11. Comparison between MAQ 7.11 and MAQ 2.4 seedlings confirmed that wind stimuli and cold shock invoke separate Ca2+ signaling pathways. Partial cDNAs encoding two tobacco calmodulin genes, NpCaM-1 and NpCaM-2, were identified and shown to have distinct nucleotide sequences that encode identical polypeptides. Expression of NpCaM-1, but not NpCaM-2, responded to wind and cold shock stimulation. Comparison of the Ca2+ dynamics with NpCaM-1 expression after stimulation suggested that wind-induced NpCaM-1 expression is regulated by a Ca2+ signaling pathway operational predominantly in the nucleus. In contrast, expression of NpCaM-1 in response to cold shock is regulated by a pathway operational predominantly in the cytoplasm. PMID:10557218
The effects of lead stress on photosynthetic function and chloroplast ultrastructure of Robinia pseudoacacia seedlings.

PubMed

Zhou, Jian; Jiang, Zeping; Ma, Jie; Yang, Lifeng; Wei, Yuan

2017-04-01

In this experiment, the effects of different lead (Pb) concentrations (0, 200, 600, 1000, 1400 mg kg -1 ) on photosynthesis and chlorophyll fluorescence in Robinia pseudoacacia seedlings were examined. As Pb concentration increased, chlorophyll a, chlorophyll b, total chlorophyll content, net photosynthetic rate, transpiration rate, stomatal conductance (g s ), and mesophyll intercellular carbon dioxide concentration were gradually reduced. Maximal photochemical efficiency, photochemical quenching, and quantum yield also decreased. However, the initial fluorescence and nonphotochemical quenching gradually increased. Chloroplasts swelled owing to local plasmolysis and lost most of their starch content, and their thylakoid lamellae gradually became disordered and loosely packed. When the chloroplast envelope was lost under high Pb stress (≥1000 mg kg -1 ), lipid globules were released into the surrounding mesophyll cell. Multiple regression analysis showed that g s and inactivity of the PSII reaction center had the greatest effect on photosynthetic function, whereas inhibition of electron transport had minimal effects on black locust seedlings under Pb stress.
A hierarchy of needs? Embryo donation, in vitro fertilisation and the provision of infertility counselling.

PubMed

Machin, Laura

2011-11-01

The aim of the paper is to examine how those working in, using and regulating assisted conception clinics discussed infertility counselling and its provision within the context of embryo donation and in vitro fertilisation. 35 participants were recruited for semi-structured, face-to-face interviews. All data were analysed using thematic analysis. The thematic analysis revealed recurring themes based upon the portrayals of infertility counselling, embryo donation and in vitro fertilisation. This paper suggests that an implicit hierarchy exists around those using assisted conception techniques and their infertility counselling requirements, which was dependent upon the assisted conception technique used. As a result, some people using assisted conception techniques felt that their needs had been overlooked due to this covert hierarchy. Those working in, using or regulating assisted conception clinics should not view infertility counselling as restricted to treatments involving donation, or solely for people within the clinical system. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.
Simulating nitrogen budgets in complex farming systems using INCA: calibration and scenario analyses for the Kervidy catchment (W. France)

NASA Astrophysics Data System (ADS)

Durand, P.

The integrated nitrogen model INCA (Integrated Nitrogen in Catchments) was used to analyse the nitrogen dynamics in a small rural catchment in Western France. The agrosystem studied is very complex, with: extensive use of different organic fertilisers, a variety of crop rotations, a structural excess of nitrogen (i.e. more animal N produced by the intensive farming than the N requirements of the crops and pastures), and nitrate retention in both hydrological stores and riparian zones. The original model features were adapted here to describe this complexity. The calibration results are satisfactory, although the daily variations in stream nitrate are not simulated in detail. Different climate scenarios, based on observed climate records, were tested; all produced a worsening of the pollution in the short term. Scenarios of alternative agricultural practices (reduced fertilisation and catch crops) were also analysed, suggesting that a reduction by 40% of the fertilisation combined with the introduction of catch crops would be necessary to stop the degradation of water quality.
Applied gamma ray spectrometry and remote sensing in delineation of nepheline syenites in rift tectonic settings

NASA Astrophysics Data System (ADS)

Chiwona, Annock Gabriel; Manning, David A. C.; Gaulton, Rachel; Cortes, Joaquin A.

2017-04-01

The United Nations (2016) observes that 'Neglected Development Minerals' including industrial minerals such as nepheline syenites have great potential for sustainable development, yet their exploitation has not been equally promoted like high value minerals. Nepheline syenites have great potential as alternative potassium (K) silicate fertiliser, as well as a source of Rare Earths. Demand for K fertiliser keeps rising by 3-3.5% annually (Jena et al., 2014) due to increased need to replace K removal from the soil (Sheldrick et al., 2002). The situation is most critical in Sub-Sahara Africa where nutrient loss due to intensive farming accounts to 22kg N, 2.5 kg P and 15 kg of K per hectare annually (Keeble, 2012). Ironically, Africa with 15% of global population, which is also expected to double by 2040 (Manning, 2015), uses only 1.5% of global K fertiliser. In this study, we use recently acquired countrywide airborne geophysical gamma ray data of Malawi (Bates & Mechennef, 2013) and satellite remote sensing data to identify nepheline syenites, suitable as sources of K silicate fertilizer, in rift tectonic settings. Initial focus was on the East African Rift System (EARS) starting with Malawi. Results from these two techniques are compared with X-ray fluorescence (XRF) geochemical analyses of sample collected from fieldwork in some potential areas of Malawi. With lessons from the Rochagem movement (Theodoro & Leonardos, 2006), identification of novel alternative potash sources in Africa will greatly benefit millions of farmers in developing countries, especially in Sub Sahara Africa where fertiliser costs are very high. Considering that high-resolution airborne geophysical data is not available in many African countries due to high costs associated with data acquisition campaigns, alternative and effective remote sensing approaches for delineating nepheline syenite rocks are necessary. References: [1] Bates M & Mechennef, F (2013) Data Acquisition Report, Sander Geophysics Limited 1:1-294. [2]Jena SK, Dhawan N, Rao DS, et al. (2014) International Journal of Mineral Processing 133: 13-22. [3] Keeble F. (2012) Nature 483 (7391): 510. [4] Manning DAC. (2015) Proceedings of Geologists' Association 126: 14-17. [5] Sheldrick W and Lingard J. (2004) Food Policy 29: 61-98. [6] Sheldrick, W., et al. (2002) Nutrient Cycling in Agroecosystems 62 (1):.61-72. [7] Theodoro, S., & Leonardos, O. (2006) Anais Da Academia Brasileira De Ciencias 78, (4):721-730. [8] ACP-EU Development Minerals Programme In partnership with UNDP, (accessed on 29/11/ 2016: http://www.undp.org/content/dam/brussels/docs/Other/Request%20for%20Applications_Neglected%20Development%20Minerals%20Workshop_Georgetown_2016.pdf)
DELLAs Regulate Chlorophyll and Carotenoid Biosynthesis to Prevent Photooxidative Damage during Seedling Deetiolation in Arabidopsis[C][W

PubMed Central

Cheminant, Soizic; Wild, Michael; Bouvier, Florence; Pelletier, Sandra; Renou, Jean-Pierre; Erhardt, Mathieu; Hayes, Scott; Terry, Matthew J.; Genschik, Pascal; Achard, Patrick

2011-01-01

In plants, light represents an important environmental signal that triggers the production of photosynthetically active chloroplasts. This developmental switch is critical for plant survival because chlorophyll precursors that accumulate in darkness can be extremely destructive when illuminated. Thus, plants have evolved mechanisms to adaptively control plastid development during the transition into light. Here, we report that the gibberellin (GA)-regulated DELLA proteins play a crucial role in the formation of functional chloroplasts during deetiolation. We show that Arabidopsis thaliana DELLAs accumulating in etiolated cotyledons derepress chlorophyll and carotenoid biosynthetic pathways in the dark by repressing the transcriptional activity of the phytochrome-interacting factor proteins. Accordingly, dark-grown GA-deficient ga1-3 mutants (that accumulate DELLAs) display a similar gene expression pattern to wild-type seedlings grown in the light. Consistent with this, ga1-3 seedlings accumulate higher amounts of protochlorophyllide (a phototoxic chlorophyll precursor) in darkness but, surprisingly, are substantially more resistant to photooxidative damage following transfer into light. This is due to the DELLA-dependent upregulation of the photoprotective enzyme protochlorophyllide oxidoreductase (POR) in the dark. Our results emphasize the role of DELLAs in regulating the levels of POR, protochlorophyllide, and carotenoids in the dark and in protecting etiolated seedlings against photooxidative damage during initial light exposure. PMID:21571951
Growth response of four species of Eastern hardwood tree seedlings exposed to ozone, acidic precipitation, and sulfur dioxide. [Prunus serotina, Acer rubrum, Quercus rubra, Liriodendron tulipifera

DOE Office of Scientific and Technical Information (OSTI.GOV)

Davis, D.D. Skelly, J.M.

1992-03-01

In 1987 a study was conducted in controlled environment chambers to determine the foliar sensitivity of tree seedlings of eight species to ozone and acidic precipitation, and to determine the influence of leaf position on symptom severity. Jensen and Dochinger conducted concurrent similar studies in Continuously Stirred Tank Reactor (CSTR) chambers with ten species of forest trees. Based on the results of these initial studies, four species representing a range in foliar sensitivity to ozone were chosen: black cherry (Prunus serotina Ehrh.), red maple (Acer rubrum L.), northern red oak (Quercus rubra L.) and yellow-poplar (Liriodendron tulipifera L.). These speciesmore » were also chosen because of their ecological and/or commercial importance in Pennsylvania. Seedlings were exposed in growth chambers simulated acid rain. In addition acute exposures to sulfur dioxide were conducted in a regime based on unpublished monitoring data collected near coal-fired power plants. The objective of this study was to determine if the pollutant treatments influenced the growth and productivity of seedlings of these four species. This information will help researchers and foresters understand the role of air pollution in productivity of eastern forests.« less
How does different arable management affect potential N mineralisation?

NASA Astrophysics Data System (ADS)

Spiegel, Heide; Sandén, Taru; Dersch, Georg; Baumgarten, Andreas

2017-04-01

The production of food and animal feed on agricultural soils and an increasing need to generate biomass for material and energy use on the limited resource soil require optimal nutrient storage and cycling. Especially nitrogen (N) should be managed as accurate as possible to ensure beneficial yields and product qualities and to avoid adverse environmental effects, e.g. N leaching into waters and gaseous losses into the atmosphere. One biological indicator to assess the site specific potential to release N is the "potential N mineralisation". This parameter can be measured by routine analysis with the anaerobic incubation method (KEENEY, 1982), modified according to KANDELER (1993) on dried soils. The results of the potential N mineralisation measurements can be classified (high: > 70 mg N kg-1 7 d-1, medium and low: 35-70 mg and ≤ 35 N kg-1 7d-1, respectively) according to the Austrian guidelines for appropriate fertilisation (BMLFUW, 2017). The results of this biological soil parameter provide information about soil fertility and the nutrient status to the farmers and can be used to adjust N fertilisation recommendations. Furthermore, AGES runs long-term field experiments since several decades. We have evaluated the effects of different agricultural management, such as organic and mineral fertilisation and tillage, on the potential N mineralisation at different sites in Austria. Our results indicate that the potential N mineralisation increases significantly after long-term organic fertilisation (farmyard manure (FYM)), after long-term incorporation of crop residues and the reduction of tillage.
Leptin and leptin receptor are detectable in equine spermatozoa but are not involved in in vitro fertilisation.

PubMed

Lange-Consiglio, Anna; Corradetti, Bruna; Perrini, Claudia; Bizzaro, Davide; Cremonesi, Fausto

2016-04-01

In human and swine, leptin (OB) has been identified in seminal plasma and leptin receptors (OB-R) on the cell surface of spermatozoa, indicating that spermatozoa are a target for OB. This hormone has also been detected in follicular fluid (FF) in women and mares, although its role requires further study. The aims of this study were to investigate the immunolocalisation and the expression of OB and OB-R in equine spermatozoa and to evaluate the involvement of OB in equine in vitro fertilisation (IVF). Since progesterone (P) and OB are both found in FF, the individual and combined effects of these two hormones were studied in equine IVF and compared with the results obtained from the use of FF for in vitro sperm preparation. For the first time, we were able to identify OB and OB-R mRNA and their corresponding proteins in equine spermatozoa. When spermatozoa were treated with OB, there was a decrease in the three motility parameters VSL, STR and LIN, commonly associated with hyperactivation, whilst the acrosome reaction rate increased (P<0.05). The fertilisation rate was 51% with FF, 46.15% with P, 43.64% with P+OB and 0% with OB alone. The percentage of eight-cell stage embryos was 18.7% with FF, 17.1% with P and 16.7% with OB+P. OB alone did not permit oocyte fertilisation, indicating that, in the horse, OB is involved in capacitation and hyperactivation but not in sperm penetration.
Membrane scaling and flux decline during fertiliser-drawn forward osmosis desalination of brackish groundwater.

PubMed

Phuntsho, Sherub; Lotfi, Fezeh; Hong, Seungkwan; Shaffer, Devin L; Elimelech, Menachem; Shon, Ho Kyong

2014-06-15

Fertiliser-drawn forward osmosis (FDFO) desalination has been recently studied as one feasible application of forward osmosis (FO) for irrigation. In this study, the potential of membrane scaling in the FDFO process has been investigated during the desalination of brackish groundwater (BGW). While most fertilisers containing monovalent ions did not result in any scaling when used as an FO draw solution (DS), diammonium phosphate (DAP or (NH4)2HPO4) resulted in significant scaling, which contributed to severe flux decline. Membrane autopsy using scanning electron microscopy (SEM), energy-dispersive x-ray spectroscopy (EDS), and x-ray diffraction (XRD) analysis indicated that the reverse diffusion of DAP from the DS to the feed solution was primarily responsible for scale formation during the FDFO process. Physical cleaning of the membrane with deionised water at varying crossflow velocities was employed to evaluate the reversibility of membrane scaling and the extent of flux recovery. For the membrane scaled using DAP as DS, 80-90% of the original flux was recovered when the crossflow velocity for physical cleaning was the same as the crossflow velocity during FDFO desalination. However, when a higher crossflow velocity or Reynolds number was used, the flux was recovered almost completely, irrespective of the DS concentration used. This study underscores the importance of selecting a suitable fertiliser for FDFO desalination of brackish groundwater to avoid membrane scaling and severe flux decline. Copyright © 2014 Elsevier Ltd. All rights reserved.

Fertilisation rate obtained with frozen-thawed boar semen supplemented with rosmarinic acid using a single insemination timed according to vulvar skin temperature changes.

PubMed

Luño, Victoria; Gil, Lydia; Olaciregui, Maite; Grandía, Juan; Ansó, Trinidad; De Blas, Ignacio

2015-03-01

Artificial insemination (AI) of sows with frozen-thawed semen usually results in lower pregnancy rates and litter sizes than the use of liquid preserved semen. The present study evaluated the effectiveness of vulvar skin temperature changes as a predictor of ovulation in sows and determined the fertility rates obtained after AI with frozen-thawed semen supplemented with rosmarinic acid (RA). Semen was collected from mature boars and cryopreserved in experimental extenders supplemented with or without 105 μM of RA. Multiparous sows were inseminated with a single dose of semen when vulvar skin temperature decreased to a value below 35 °C. Intrauterine insemination was performed using 1.5 × 109 spermatozoa. The sows were slaughtered 48 h after AI and the embryos and oocytes were recovered from the oviducts. Total and progressive motility, viability and acrosome integrity were significantly (P < 0.05) higher in RA-supplemented semen samples compared with the control. Fertilisation occurred in all sows inseminated in the study, although there were no significant differences between the experimental groups. Sows inseminated with RA-supplemented semen showed a slight increase in the number of embryos recovered as compared to sows inseminated with control semen. In conclusion, insemination according to vulvar skin temperature changes resulted in successful fertilisation in all sows, although supplementation of the freezing media with RA did not improve the fertilising ability of frozen-thawed boar sperm.
Effects of seed production, seedbed condition, and overstory basal area on the establishment of shortleaf pine seedlings in the Ouachita Mountains

Treesearch

Michael G. Shelton

1995-01-01

Some of the factors affecting the establishment of shortleaf pine regeneration after the initial treatments implementing uneven-aged silviculture in shortleaf pine-hardwood stands are quantitatively described in this publication.
Extensive variation, but not local adaptation in an Australian alpine daisy.

PubMed

Hirst, Megan J; Sexton, Jason P; Hoffmann, Ary A

2016-08-01

Alpine plants often occupy diverse habitats within a similar elevation range, but most research on local adaptation in these plants has focused on elevation gradients. In testing for habitat-related local adaptation, local effects on seed quality and initial plant growth should be considered in designs that encompass multiple populations and habitats. We tested for local adaptation across alpine habitats in a morphologically variable daisy species, Brachyscome decipiens, in the Bogong High Plains in Victoria, Australia. We collected seed from different habitats, controlled for maternal effects through initial seed size estimates, and characterized seedling survival and growth in a field transplant experiment. We found little evidence for local adaptation for survival or plant size, based on three adaptation measures: Home versus Away, Local versus Foreign, and Sympatric versus Allopatric (SA). The SA measure controlled for planting site and population (site-of-origin) effects. There were significant differences due to site-of-origin and planting site effects. An important confounding factor was the size of plants directly after transplantation of seedlings, which had a large impact on subsequent seedling survival and growth. Initial differences in plant width and height influenced subsequent survival across the growing season but in opposing directions: wide plants had higher survival, but tall plants had lower survival. In an additional controlled garden experiment at Cranbourne Royal Botanic Gardens, site-of-origin effects detected in the field experiments disappeared under more benign homogeneous conditions. Although B. decipiens from different source areas varied significantly when grown across a range of alpine habitats, these differences did not translate into a local or habitat-related fitness advantage. This lack of local advantage may signal weak past selection, and/or weak adaptive transgeneration (plasticity) effects.
Whitebark pine facilitation at treeline: potential interactions for disruption by an invasive pathogen.

PubMed

Tomback, Diana F; Blakeslee, Sarah C; Wagner, Aaron C; Wunder, Michael B; Resler, Lynn M; Pyatt, Jill C; Diaz, Soledad

2016-08-01

In stressful environments, facilitation often aids plant establishment, but invasive plant pathogens may potentially disrupt these interactions. In many treeline communities in the northern Rocky Mountains of the U.S. and Canada, Pinus albicaulis, a stress-tolerant pine, initiates tree islands at higher frequencies than other conifers - that is, leads to leeward tree establishment more frequently. The facilitation provided by a solitary (isolated) P. albicaulis leading to tree island initiation may be important for different life-history stages for leeward conifers, but it is not known which life-history stages are influenced and protection provided. However, P. albicaulis mortality from the non-native pathogen Cronartium ribicola potentially disrupts these facilitative interactions, reducing tree island initiation. In two Rocky Mountain eastern slope study areas, we experimentally examined fundamental plant-plant interactions which might facilitate tree island formation: the protection offered by P. albicaulis to leeward seed and seedling life-history stages, and to leeward krummholz conifers. In the latter case, we simulated mortality from C. ribicola for windward P. albicaulis to determine whether loss of P. albicaulis from C. ribicola impacts leeward conifers. Relative to other common solitary conifers at treeline, solitary P. albicaulis had higher abundance. More seeds germinated in leeward rock microsites than in conifer or exposed microsites, but the odds of cotyledon seedling survival during the growing season were highest in P. albicaulis microsites. Planted seedling survival was low among all microsites examined. Simulating death of windward P. albicaulis by C. ribicola reduced shoot growth of leeward trees. Loss of P. albicaulis to exotic disease may limit facilitation interactions and conifer community development at treeline and potentially impede upward movement as climate warms.
Light-regulated and organ-specific expression of types 1, 2, and 3 light-harvesting complex b mRNAs in Ginkgo biloba.

PubMed Central

Chinn, E; Silverthorne, J; Hohtola, A

1995-01-01

In a prior study (E. Chinn and J. Silverthorne [1993] Plant Physiol 103: 727-732) we showed that the gymnosperm Ginkgo biloba was completely dependent on light for chlorophyll synthesis and chloroplast development and that expression of light-harvesting complex b (Lhcb) mRNAs was substantially increased by light. However, dark-grown seedlings that were transferred to constant white light took significantly longer than angiosperm seedlings to initiate a program of photomorphogenesis and the stems failed to green completely. We have prepared type-specific probes for mRNAs encoding major polypeptides of light-harvesting complex II (Lhcb1, Lhcb2, and Lhcb3) and have used these to analyze the expression of individual Lhcb mRNAs during greening. All three sequences accumulated in the top portions of dark-grown seedlings transferred to light, but, as was seen previously for total Lhcb mRNAs, there was a transient, reproducible decline in the levels of all three mRNAs after 4 d in the light. This transient decrease in Lhcb mRNA levels was not paralleled by a decrease in Chl accumulation. By contrast, there were significantly lower levels of all three Lhcb mRNAs in the lower portions of greening dark-grown stems as well as lower Chl levels. We conclude that although the tops of the plants have the capacity to etiolate and green, Gingko seedling stems continue a program of development into woody tissue in darkness that precludes greening when the seedlings are transferred to the light. PMID:7724674
Growth strategies and threshold responses to water deficit modulate effects of warming on tree seedlings from forest to alpine

USGS Publications Warehouse

Lazarus, Brynne E.; Castanha, Cristina; Germino, Matthew; Kueppers, Lara M.; Moyes, Andrew B.

2018-01-01

1.Predictions of upslope range shifts for tree species with warming are based on assumptions of moisture stress at lower elevation limits and low temperature stress at high elevation limits. However, recent studies have shown that warming can reduce tree seedling establishment across the entire gradient from subalpine forest to alpine via moisture limitation. Warming effects also vary with species, potentially resulting in community shifts in high elevation forests. 2.We examined the growth and physiology underlying effects of warming on seedling demographic patterns. We evaluated dry mass (DM), root length, allocation above- and belowground, and relative growth rate (RGR) of whole seedlings, and their ability to avoid or endure water stress via water-use efficiency and resisting turgor loss, for Pinus flexilis, Picea engelmannii and Pinus contorta seeded below, at, and above treeline in experimentally warmed, watered, and control plots in the Rocky Mountains, USA. We expected that growth and allocation responses to warming would relate to moisture status and that variation in drought tolerance traits would explain species differences in survival rates. 3.Across treatments and elevations, seedlings of all species had weak turgor-loss resistance, and growth was marginal with negative RGR in the first growth phase (-0.01 to -0.04 g/g/d). Growth was correlated with soil moisture, particularly in the relatively small-seeded P. contorta and P. engelmannii. P. flexilis, known to have the highest survivorship, attained the greatest DM and longest root but was also the slowest growing and most water-use-efficient. This was likely due to its greater reliance on seed reserves. Seedlings developed 15% less total DM, 25% less root DM, and 11% shorter roots in heated compared to unheated plots. Higher temperatures slightly increased DM, root length and RGR where soils were wettest, but more strongly decreased these variables under drier conditions. 4.Synthesis: The surprising heat-inhibition of tree seedling establishment at the cold edge of forests appears to have a physiological basis: newly germinated seedlings have poor moisture stress tolerance, which appears related to marginal initial growth and heavy reliance on seed reserves. Variation in these attributes among tree species at treeline helps explain their different climate responses.
A spaceflight experiment to investigate the effects of a range of unilateral blue light phototropic stimulations on the movements of wheat coleoptiles (6-IML-1)

NASA Technical Reports Server (NTRS)

Heathcote, David G.

1992-01-01

In 1978, in response to an announcement of opportunity by NASA, two independent groups proposed related investigations to study the response of seedling plants to photostimulations at microgravity. The spaceflight experiment is known by its NASA acronym, FOTRAN. The scientific objectives behind the experiment are outlined, and a brief description of the spaceflight equipment and the experimental procedures developed to accomplish the aims of the experiment are presented. By reference to the results of ground-based studies, the likely scientific returns of the FOTRAN experiment will be assessed. The experiment is designed to investigate the effects of a range of blue light stimulations on the movements of wheat coleoptiles at zero-g. The seedlings will be dark-grown, and their movements assessed from infrared time-lapse video recordings made during flight. The photostimulus may be expected to modulate circumnutations of the coleoptiles, by synchronizing, initiating or amplifying these rhythmic movements, and to initiate the classic phototropic response.
Photoprotection, photosynthesis and growth of tropical tree seedlings under near-ambient and strongly reduced solar ultraviolet-B radiation.

PubMed

Krause, G Heinrich; Jahns, Peter; Virgo, Aurelio; García, Milton; Aranda, Jorge; Wellmann, Eckard; Winter, Klaus

2007-10-01

Seedlings of two late-successional tropical rainforest tree species, Tetragastris panamensis (Engler) O. Kuntze and Calophyllum longifolium (Willd.), were field grown for 3-4 months at an open site near Panama City (9 degrees N), Panama, under plastic films that either transmitted or excluded most solar UV-B radiation. Experiments were designed to test whether leaves developing under bright sunlight with strongly reduced UV-B are capable of acclimating to near-ambient UV-B conditions. Leaves of T. panamensis that developed under near-ambient UV-B contained higher amounts of UV-absorbing substances than leaves of seedlings grown under reduced UV-B. Photosynthetic pigment composition, content of alpha-tocopherol, CO(2) assimilation, potential photosystem II (PSII) efficiency (evaluated by F(v)/F(m) ratios) and growth of T. panamensis and C. longifolium did not differ between seedlings developed under near-ambient and reduced solar UV-B. When seedlings were transferred from the reduced UV-B treatment to the near-ambient UV-B treatment, a pronounced inhibition of photosynthetic capacity was observed initially in both species. UV-B-mediated inhibition of photosynthetic capacity nearly fully recovered within 1 week of the transfer in C. longifolium, whereas in T. panamensis an about 35% reduced capacity of CO(2) uptake was maintained. A marked increase in UV-absorbing substances was observed in foliage of transferred T. panamensis seedlings. Both species exhibited enhanced mid-day photoinhibition of PSII immediately after being transferred from the reduced UV-B to the near-ambient UV-B treatment. This effect was fully reversible within 1d in T. panamensis and within a few days in C. longifolium. The data show that leaves of these tropical tree seedlings, when developing in full-spectrum sunlight, are effectively protected against high solar UV-B radiation. In contrast, leaves developing under conditions of low UV-B lacked sufficient UV protection. They experienced a decline in photosynthetic competence when suddenly exposed to near-ambient UV-B levels, but exhibited pronounced acclimative responses.
The effectiveness of surface liming in ameliorating the phytotoxic effects of soil contaminated by copper acid leach pad solution in an arid ecosystem

NASA Astrophysics Data System (ADS)

Golos, Peter

2016-04-01

Revegetation of sites following soil contamination can be challenging especially in identifying the most effective method for ameliorating phytotoxic effects in arid ecosystems. This study at a copper mine in the Great Sandy Desert of Western Australia investigated vegetation restoration of a site contaminated by acid (H2SO4) leach pad solution. Elevated soil copper at low soil pH is phytotoxic to plant roots inhibiting root elongation. In arid ecosystems where rapid root growth is crucial for seedling survival post germination physical or chemical barriers to root growth need to be identified and ameliorated. Initial attempt at rehabilitation of contaminated site with hydrated lime (CaOH2) at 2 tonnes/ha followed by ripping to 30 cm depth then seeding was ineffective as successful seedling emergence was followed by over 90% seedling mortality which was 10-fold greater than seedling mortality in an uncontaminated reference site. High mortality was attributed to seedling roots being impededed as soil water was more than 3-fold greater at 5 to 40 cm depth in contaminated site than reference site. In response to high seedling mortality after emergence test pits were dug to 1 m deep to collect soil samples at 10 cm intervals for phytotoxicity testing and to measure soil pH-CaCl2, copper (DPTA ion extraction), electrical conductivity and gravimetric water content in three replicate pits at three replicate sites. Also, soil impedance was measured down the soil profile at 5 cm intervals at six replicate points/pit. For phytotoxicity testing soil samples were placed into three replicate plastic pots/sample and seeded with 10 seeds of Avena sativa and watered daily. Seedlings were harvested after at least two weeks after seedling emergence and rooting depth in pots measured. There was no difference in seedling emergence and survival of seedlings between contaminated and uncontaminated soil samples however mean seedling root growth was significantly lower in soil samples collected at >10 cm depth than the control. Mean soil pH at 0-10 cm was higher (>7.2) at all sites treated with lime compared to uncontaminated soil (5.5). At depths greater than 10 cm soil pH was <4.6. Soil copper was >16 mg/kg in all contaminated soil samples compared to 0.5 mg/kg in control. High seedling mortality in contaminated site is attributed to low soil pH and elevated soil copper levels which inhibited plant root growth and hence access to soil water. While surface liming of soil increased soil pH ameliorating the effect of elevated soil copper, this was only effective in the top 10 cm due to low solubility of hydrated lime. To improve seedling survival lime will need to be incorporated into the contaminated soil profile to allow plants to access soil water at depth. This study highlights the importance of the need to assess the phytotoxic effects of soil contamination and the effectiveness of amelioration treatments and with proper reference to its ecological context. To improve the success of vegetation restoration of sites contaminated with acidic copper solution, lime needs to be incorporated into the contaminated soil profile to allow plant roots to access soil water at depth. This study highlights the importance of the need to assess the phytotoxic effects of soil contamination and the effectiveness of amelioration treatments and with proper reference to its ecological context.
Phenylalanine derived cyanogenic diglucosides from Eucalyptus camphora and their abundances in relation to ontogeny and tissue type.

PubMed

Neilson, Elizabeth H; Goodger, Jason Q D; Motawia, Mohammed Saddik; Bjarnholt, Nanna; Frisch, Tina; Olsen, Carl Erik; Møller, Birger Lindberg; Woodrow, Ian E

2011-12-01

The cyanogenic glucoside profile of Eucalyptus camphora was investigated in the course of plant ontogeny. In addition to amygdalin, three phenylalanine-derived cyanogenic diglucosides characterized by unique linkage positions between the two glucose moieties were identified in E. camphora tissues. This is the first time that multiple cyanogenic diglucosides have been shown to co-occur in any plant species. Two of these cyanogenic glucosides have not previously been reported and are named eucalyptosin B and eucalyptosin C. Quantitative and qualitative differences in total cyanogenic glucoside content were observed across different stages of whole plant and tissue ontogeny, as well as within different tissue types. Seedlings of E. camphora produce only the cyanogenic monoglucoside prunasin, and genetically based variation was observed in the age at which seedlings initiate prunasin biosynthesis. Once initiated, total cyanogenic glucoside concentration increased throughout plant ontogeny with cyanogenic diglucoside production initiated in saplings and reaching a maximum in flower buds of adult trees. The role of multiple cyanogenic glucosides in E. camphora is unknown, but may include enhanced plant defense and/or a primary role in nitrogen storage and transport. Copyright © 2011 Elsevier Ltd. All rights reserved.
Microsite and elevation zone effects on seed pilferage, germination, and seedling survival during early whitebark pine recruitment.

PubMed

Pansing, Elizabeth R; Tomback, Diana F; Wunder, Michael B; French, Joshua P; Wagner, Aaron C

2017-11-01

Tree recruitment is a spatially structured process that may undergo change over time because of variation in postdispersal processes. We examined seed pilferage, seed germination, and seedling survival in whitebark pine to determine whether 1) microsite type alters the initial spatial pattern of seed caches, 2) higher abiotic stress (i.e. higher elevations) exacerbates spatial distribution changes, and 3) these postdispersal processes are spatially clustered. At two study areas, we created a seed distribution pattern by burying seed caches in microsite types frequently used by whitebark pine's avian seed disperser (Clark's nutcracker) in upper subalpine forest and at treeline, the latter characterized by high abiotic environmental stress. We monitored caches for two years for pilferage, germination, and seedling survival. Odds of pilferage (both study areas), germination (northern study area), and survival (southern study area) were higher at treeline relative to subalpine forest. At the southern study area, we found higher odds of 1) pilferage near rocks and trees relative to no object in subalpine forest, 2) germination near rocks relative to trees within both elevation zones, and 3) seedling survival near rocks and trees relative to no object at treeline. No microsite effects were detected at the northern study area. Findings indicated that the microsite distribution of seed caches changes with seed/seedling stage. Higher odds of seedling survival near rocks and trees were observed at treeline, suggesting abiotic stress may limit safe site availability, thereby shifting the spatial distribution toward protective microsites. Higher odds of pilferage at treeline, however, suggest rodents may limit treeline recruitment. Further, odds of pilferage were higher near rocks and trees relative to no object in subalpine forest but did not differ among microsites at treeline, suggesting pilferage can modulate the spatial structure of regeneration, a finding supported by limited clustering of postdispersal processes.
Morphological indicators of stock quality and field performance of red oak (Quercus rubra L.) seedling underplanted in a central Ontario shelterwood

Treesearch

Daniel C. Dey; William C. Parker

1997-01-01

Initial stem diameter of bareroot red oak planting stock was a better morphological indicator of future height and diameter growth in a shelterwood underplanting than were initial shoot length and number of first-order lateral roots. Stem diameter near the root collar provides an integrated measure of the growth potential of red oak planting stock because of its strong...
The influence of body mass index to in-vitro fertilisation treatment outcome, risk of miscarriage and pregnancy outcome.

PubMed

Thum, M Y; El-Sheikhah, A; Faris, R; Parikh, J; Wren, M; Ogunyemi, T; Gafar, A; Abdalla, H

2007-10-01

The aim of this work was to evaluate the effects of extreme body mass index (BMI) on assisted reproductive treatment outcome and pregnancy outcome. This is a descriptive cohort study that evaluated 8,145 consecutive in-vitro fertilisation/intracytoplasmic sperm injection-embryo transfer (IVF/ICSI-ET) cycles in which BMI were known, from July 1997 to June 2005 in an inner London major fertility clinic. The data were collected prospectively and analysed retrospectively on women undergoing IVF/ICSI and ET. Patients' weight and height were established prior to treatment. IVF/ICSI treatment was then started using either a long or an antagonist protocol. Patients were divided into five groups: Group A (BMI < 19); Group B (BMI between 19 and 25.9); Group C (BMI between 26 and 30.9); Group D (BMI between 31 and 35.9); Group E (BMI > 36). The main outcomes measured were number of eggs collected, fertilisation rate, number of embryos available for transfer, pregnancy rate (PR), live-birth rate (LBR) and miscarriage rate (MR). The results showed no significant difference in the average number of days taking follicle stimulating hormone (FSH) for ovarian stimulation, the average amount of gonadotrophin used for stimulation, number of eggs collected and fertilisation rate. The pregnancy rate, miscarriage rate and the live-birth rate were not statistically different between all groups. However, in group E the miscarriage rate was significantly higher and the LBR was statistically lower compared with group B. We concluded that extreme BMI did not affect the super-ovulation outcome fertilisation rate and pregnancy rate. Women with a BMI > 35 had a higher miscarriage rate and hence a lower live-birth rate, but a reasonable pregnancy and live-birth rate can be achieved. For women with a BMI < 20 there was no difference in assisted reproduction treatment (ART) outcome and pregnancy outcome when compared with women with a normal BMI. This information should be used to advise patients who wish to embark on ART with extreme BMI.
Field evaluation of in situ remediation of Cd-contaminated soil using four additives, two foliar fertilisers and two varieties of pakchoi.

PubMed

Feng, Renwei; Qiu, Weiwen; Lian, Fei; Yu, Zhihong; Yang, YiXin; Song, Zhengguo

2013-07-30

This study was conducted to determine the optimal planting mode for pakchoi (Brassica rapa chinensis) in Cd-contaminated soil to reduce the accumulation of Cd in the edible parts while maintaining yields. Four additives (red mud (RM), silicon calcium fertiliser (SC), spodium (SP) and calcium magnesium phosphate (CMP)), two foliar fertilisers (Ca and Zn) and two varieties of pakchoi (Aijiaohuang (AJ) and Baixuegongzhu (BX)) were used in this study. The results show that the addition of SC and RM had an effect, but the other additives did not appear to increase the biomasses of AJ and BX. In some cases, the growth responses of AJ and BX to the same treatment were different. Extra additions of Ca or Zn to additive-treated pakchoi did not help the additives stimulate the growth of AJ and BX, except for SC-treated AJ and BX and SP-treated AJ. The SC and CMP additives significantly reduced the available Cd concentration in both the AJ soil and the BX soil; however, they did not significantly decrease the Cd concentration in the aboveground parts of AJ and BX. The RM treatments (for both levels) and some treatments containing SP reduced the available Cd concentration in the soils and reduced the accumulation of Cd in the two pakchoi varieties. Additions of Ca or Zn fertiliser significantly reduced the Cd concentration in the aboveground parts of AJ and BX. However, when Ca or Zn was sprayed on the additive-treated AJ and BX, they did not help the additives reduce the Cd accumulation in the aboveground parts of AJ and BX, except for the additive CMP. This study shows that RM may be an optimal amendment to reduce the accumulation of Cd in the edible part of pakchoi while simultaneously maintaining yields. The utilisation of Ca or Zn as a foliar fertiliser to additive-treated pakchoi showed positive effects only under some conditions. Copyright © 2013 Elsevier Ltd. All rights reserved.
Lagrangian Analysis of Kerguelen's Naturally Iron-fertilised Phytoplankton Bloom

NASA Astrophysics Data System (ADS)

Della Penna, A.; Trull, T. W.; Grenier, M.; Wotherspoon, S.; Johnson, C.; De Monte, S.; d'Ovidio, F.

2015-12-01

The role of iron as a limiting micro-nutrient for primary production in High Nutrient Low Chlorophyll regions has been highlighted by paleoceanography, artificial fertilisation experiments and observed naturally fertilised systems. Examples of natural fertilisation have suggested that (sub-)mesoscale (1-100 km, days-months) horizontal transport modulates and structures the spatial and temporal extent of iron enrichment, phytoplankton production and biogeography. Here we combine different satellite products (altimetry, ocean color, PHYSAT), in-situ sampling, drifting floats and autonomous profilers to analyse the naturally iron-fertilised phytoplankton bloom of the Kerguelen region (Southern Ocean). Considering the Kerguelen Plateau as the main local source of iron, we compute two Lagrangian diagnostics: the "age" - how long before a water parcel has touched the plateau- and the "origin" - the latitude where a water parcel has left the plateau. First, we verify that these altimetry-defined diagnostics' spatial patterns -computed using geostrophic and Ekman corrected velocity fields- are coherent with the ones structuring the trajectories of more than 100 drifters and that trends in surface Chlorophyll (Chl) present an overall agreement with total column content (yet with ~2-3x differences in dynamic ranges likely due to the varying presence of Chl below the mixed layer). Second, assuming a first-order removal, we fit "age" with iron measurements and we estimate removal rates for bloom and abiotic conditions of respectively 0.058 and 0.041 1/d. Then, we relate "age" and "origin" with locations of high Chl concentrations and diatom-dominance. We find out that locations of high Chl concentration correspond to water parcels that have recently left the plateau. Furthermore, general additive models reveal that recently enriched waters are more likely to present a diatom dominance. However, the expected exponential fit varies within the geographic domain suggesting that other mechanisms may affect diatom dominance. These findings suggest that, in spite of their simple definitions, "age" and "origin" can be used to locate hotspots of primary production, study diatom-dominance biogeography and guide adaptive sampling stategies for biogeochemical fieldwork.
Phytoplankton-Specific Response to Enrichment of Phosphorus-Rich Surface Waters with Ammonium, Nitrate, and Urea

PubMed Central

Donald, Derek B.; Bogard, Matthew J.; Finlay, Kerri; Bunting, Lynda; Leavitt, Peter R.

2013-01-01

Supply of anthropogenic nitrogen (N) to the biosphere has tripled since 1960; however, little is known of how in situ response to N fertilisation differs among phytoplankton, whether species response varies with the chemical form of N, or how interpretation of N effects is influenced by the method of analysis (microscopy, pigment biomarkers). To address these issues, we conducted two 21-day in situ mesocosm (3140 L) experiments to quantify the species- and genus-specific responses of phytoplankton to fertilisation of P-rich lake waters with ammonium (NH4 +), nitrate (NO3 −), and urea ([NH2]2CO). Phytoplankton abundance was estimated using both microscopic enumeration of cell densities and high performance liquid chromatographic (HPLC) analysis of algal pigments. We found that total algal biomass increased 200% and 350% following fertilisation with NO3 − and chemically-reduced N (NH4 +, urea), respectively, although 144 individual taxa exhibited distinctive responses to N, including compound-specific stimulation (Planktothrix agardhii and NH4 +), increased biomass with chemically-reduced N alone (Scenedesmus spp., Coelastrum astroideum) and no response (Aphanizomenon flos-aquae, Ceratium hirundinella). Principle components analyses (PCA) captured 53.2–69.9% of variation in experimental assemblages irrespective of the degree of taxonomic resolution of analysis. PCA of species-level data revealed that congeneric taxa exhibited common responses to fertilisation regimes (e.g., Microcystis aeruginosa, M. flos-aquae, M. botrys), whereas genera within the same division had widely divergent responses to added N (e.g., Anabaena, Planktothrix, Microcystis). Least-squares regression analysis demonstrated that changes in phytoplankton biomass determined by microscopy were correlated significantly (p<0.005) with variations in HPLC-derived concentrations of biomarker pigments (r 2 = 0.13–0.64) from all major algal groups, although HPLC tended to underestimate the relative abundance of cyanobacteria. Together, these findings show that while fertilisation of P-rich lakes with N can increase algal biomass, there is substantial variation in responses of genera and divisions to specific chemical forms of added N. PMID:23349705
Phytoplankton-specific response to enrichment of phosphorus-rich surface waters with ammonium, nitrate, and urea.

PubMed

Donald, Derek B; Bogard, Matthew J; Finlay, Kerri; Bunting, Lynda; Leavitt, Peter R

2013-01-01

Supply of anthropogenic nitrogen (N) to the biosphere has tripled since 1960; however, little is known of how in situ response to N fertilisation differs among phytoplankton, whether species response varies with the chemical form of N, or how interpretation of N effects is influenced by the method of analysis (microscopy, pigment biomarkers). To address these issues, we conducted two 21-day in situ mesocosm (3140 L) experiments to quantify the species- and genus-specific responses of phytoplankton to fertilisation of P-rich lake waters with ammonium (NH(4)(+)), nitrate (NO(3)(-)), and urea ([NH(2)](2)CO). Phytoplankton abundance was estimated using both microscopic enumeration of cell densities and high performance liquid chromatographic (HPLC) analysis of algal pigments. We found that total algal biomass increased 200% and 350% following fertilisation with NO(3)(-) and chemically-reduced N (NH(4)(+), urea), respectively, although 144 individual taxa exhibited distinctive responses to N, including compound-specific stimulation (Planktothrix agardhii and NH(4)(+)), increased biomass with chemically-reduced N alone (Scenedesmus spp., Coelastrum astroideum) and no response (Aphanizomenon flos-aquae, Ceratium hirundinella). Principle components analyses (PCA) captured 53.2-69.9% of variation in experimental assemblages irrespective of the degree of taxonomic resolution of analysis. PCA of species-level data revealed that congeneric taxa exhibited common responses to fertilisation regimes (e.g., Microcystis aeruginosa, M. flos-aquae, M. botrys), whereas genera within the same division had widely divergent responses to added N (e.g., Anabaena, Planktothrix, Microcystis). Least-squares regression analysis demonstrated that changes in phytoplankton biomass determined by microscopy were correlated significantly (p<0.005) with variations in HPLC-derived concentrations of biomarker pigments (r(2) = 0.13-0.64) from all major algal groups, although HPLC tended to underestimate the relative abundance of cyanobacteria. Together, these findings show that while fertilisation of P-rich lakes with N can increase algal biomass, there is substantial variation in responses of genera and divisions to specific chemical forms of added N.
Selenium speciation in wheat grain varies in the presence of nitrogen and sulphur fertilisers.

PubMed

Duncan, Elliott G; Maher, William A; Jagtap, Rajani; Krikowa, Frank; Roper, Margaret M; O'Sullivan, Cathryn A

2017-08-01

This study investigated whether selenium species in wheat grains could be altered by exposure to different combinations of nitrogen (N) and sulphur (S) fertilisers in an agronomic biofortification experiment. Four Australian wheat cultivars (Mace, Janz, Emu Rock and Magenta) were grown in a glasshouse experiment and exposed to 3 mg Se kg -1 soil as selenate (Se VI ). Plants were also exposed to 60 mg N kg -1 soil as urea and 20 mg S kg -1 soil as gypsum in a factorial design (N + S + Se; N + Se; S + Se; Se only). Plants were grown to maturity with grain analysed for total Se concentrations via ICP-MS and Se species determined via HPLC-ICP-MS. Grain Se concentrations ranged from 22 to 70 µg Se g -1 grain (dry mass). Selenomethionine (SeMet), Se-methylselenocystine (MeSeCys), selenohomolanthionine (SeHLan), plus a large concentration of uncharacterised Se species were found in the extracts from grains. SeMet was the major Se species identified accounting for between 9 and 24 µg Se g -1 grain. Exposure to different N and S fertiliser combinations altered the SeMet content of Mace, Janz and Emu Rock grain, but not that of Magenta. MeSeCys and SeHLan were found in far lower concentrations (<4 µg Se g -1 grain). A large component of the total grain Se was uncharacterisable (>30 % of total grain Se) in all samples. When N fertiliser was applied (with or without S), the proportion of uncharacterisable Se increased between 60 and 70 % of the total grain Se. The data presented here indicate that it is possible to alter the content of individual Se species in wheat grains via biofortification combined with manipulation of N and S fertiliser regimes. This has potential significance in alleviating or combating both Se deficiency and Se toxicity effects in humans.
The right to be born.

PubMed

Davey, D A

1989-01-01

The right to be born embodies several different rights: the right to be conceived, the right to be implanted in the uterus, and the right to live (or not be aborted). The right to be conceived, or the right of parents to reproduce, may depend upon circumstances. Do couples have the right to have children to whom they cannot offer an adequate upbringing? Do couples have the right to have as many children as they wish if in this way they will reduce the amount of food available to other families? Is the right to have children coupled with a responsibility not to have more children than a community, a country or the world can support? Fertilisation occurs in the fallopian tube, but only about 30% of fertilised ova normally become successfully implanted in the uterus. Fertilisation can also be achieved in a test tube and the resultant embryo then implanted in the mother's uterus to grow into a "test tube baby". Is it ethical to allow the use of donor sperm or ova, a surrogate mother, experimentation on embryos, and what should be done with "spare" embryos? The British Unborn Child (Protection) Bill 1986 prohibits anyone from possessing a fertilised embryo unless it is for the purpose of enabling a specific women to have a child. The right to live and not be aborted may involve a conflict of interests between a mother and her unborn child. A mother may claim absolute rights over her own body, including the right to have an abortion if she desires.(ABSTRACT TRUNCATED AT 250 WORDS)
The effect of endometriosis on in vitro fertilisation outcome: a systematic review and meta-analysis.

PubMed

Harb, H M; Gallos, I D; Chu, J; Harb, M; Coomarasamy, A

2013-10-01

Endometriosis is found in 0.5-5% of fertile women and 25-40% of infertile women. It is known that endometriosis is associated with infertility, but there is uncertainty whether women with endometriosis have adverse pregnancy outcomes in in vitro fertilisation (IVF) treatment. To explore the association between endometriosis and IVF outcome. Searches were conducted on MEDLINE, EMBASE, Cochrane Library and Web of Science (inception, December 2012) in all languages, together with reference lists of retrieved papers. Studies comparing IVF outcome in women with endometriosis with women without endometriosis. Patients were classified by stage of endometriosis. The outcomes were fertilisation, implantation, clinical pregnancy and live birth rates. Study selection was conducted independently by two reviewers. The Newcastle-Ottawa Quality Assessment Scale was used for quality assessment. Data extraction was conducted independently by two reviewers. Relative risks from individual studies were meta-analysed. Twenty-seven observational studies were included, comprising 8984 women. Meta-analysis of these studies showed that fertilisation rates were reduced in stage I/II of endometriosis (relative risk [RR] = 0.93, 95% confidence interval [95% CI] 0.87-0.99, P = 0.03). There was a decrease in the implantation rate (RR = 0.79, 95% CI 0.67-0.93, P = 0.006) and clinical pregnancy rate (RR = 0.79, 95% CI 0.69-0.91, P = 0.0008) in women with stage III/IV endometriosis undergoing IVF treatment. The presence of severe endometriosis (stage III/IV) is associated with poor implantation and clinical pregnancy rates in women undergoing IVF treatment. © 2013 RCOG.

The effects of anxiety and depression on in vitro fertilisation outcomes of infertile Chinese women.

PubMed

Xu, Hongmei; Ouyang, Nengyong; Li, Ruiqi; Tuo, Ping; Mai, Meiqi; Wang, Wenjun

2017-01-01

The object was to assess anxiety and depression during in vitro fertilisation (IVF) treatment and determine IVF-related psychological factors in infertile Chinese women. The self-rating anxiety scale (SAS) and self-rating depression scale (SDS) were used to evaluate anxiety and depression among 842 patients, respectively. A univariate analysis was used to compare variables among three SAS groups and three SDS groups. Anxiety and depression were both represented in 21.3% of the cases. Patients <35 years tended to be more anxious. In women <35 years, the SDS scores were higher with lower educational backgrounds and female or couple's infertility, while the SAS scores were higher in female or couple's infertility. In older ones, the SDS scores were higher in those with lower educational backgrounds and longer time for infertility, while the SAS scores were higher in those with lower educational backgrounds. In SAS groups 1-3, the embryo availability was 5.0 (3.0-8.0), 5.0 (3.0-8.0), and 3.0 (2.0-4.5) (p = .013); and the fertilisation rate was 91.9, 90.4, and 81.8% (p < .001), respectively. We concluded that infertile women experience anxiety and depression during IVF treatment, especially in women <35 years. Younger women with female infertility would be more anxious and depressive while higher education can protect them from depression. In older ones, they would experience more depressive with longer time for infertility and be less anxious and depressive with higher education. Anxiety affects the fertilisation rate and embryo availability.
Iron and nutrient content of wind-erodible sediment in the ephemeral river valleys of Namibia

NASA Astrophysics Data System (ADS)

Dansie, A. P.; Wiggs, G. F. S.; Thomas, D. S. G.

2017-08-01

Research concerning the global distribution of aeolian dust sources has principally focussed on salt/clay pan and desiccated lacustrine emission areas. In southern Africa such sources are identified as Etosha Pan in northern Namibia and Makgadikgadi Pans in northern Botswana. Dust emitting from ephemeral river valleys, however, has been largely overlooked. Rivers are known nutrient transport pathways and the flooding regimes of ephemeral river valleys frequently replenish stores of fine sediment which, on drying, can become susceptible to aeolian erosion. Such airborne sediment may be nutrient rich and thus be significant for the fertilisation of marine waters once deposited. This study investigates the dust source sediments from three ephemeral river valleys in Namibia in terms of their particle size distribution and their concentrations of bioavailable N, P and Fe. We compare the nutrient content of these sediments from the ephemeral river valleys to those collected from Etosha and Makgadikgadi Pans and consider their relative ocean fertilising potential. Our results show that the ephemeral river valleys contain fine grained sediment similar in physical character to Etosha and Makgadikgadi Pans yet they have up to 43 times greater concentrations of bioavailable iron and enriched N and P macronutrients that are each important for ocean fertilisation. The known dust-emitting river valleys of Namibia may therefore be contributing a greater fertilisation role in the adjacent marine system than previously considered, and not-yet investigated. Given this finding a re-assessment of the potential role of ephemeral river valleys in providing nutrient-rich sediment into the aeolian and marine systems in other dryland areas is necessary.
Irrigation management and phosphorus addition alter the abundance of carbon dioxide-fixing autotrophs in phosphorus-limited paddy soil.

PubMed

Wu, Xiaohong; Ge, Tida; Yan, Wende; Zhou, Juan; Wei, Xiaomeng; Chen, Liang; Chen, Xiangbi; Nannipieri, Paolo; Wu, Jinshui

2017-12-01

In this study, we assessed the interactive effects of phosphorus (P) application and irrigation methods on the abundances of marker genes (cbbL, cbbM, accA and aclB) of CO2-fixing autotrophs. We conducted rice-microcosm experiments using a P-limited paddy soil, with and without the addition of P fertiliser (P-treated-pot (P) versus control pot (CK)), and using two irrigation methods, namely alternate wetting and drying (AWD) and continuous flooding (CF). The abundances of bacterial 16S rRNA, archaeal 16S rRNA, cbbL, cbbM, accA and aclB genes in the rhizosphere soil (RS) and bulk soil (BS) were quantified. The application of P significantly altered the soil properties and stimulated the abundances of Bacteria, Archaea and CO2-fixation genes under CF treatment, but negatively influenced the abundances of Bacteria and marker genes of CO2-fixing autotrophs in BS soils under AWD treatment. The response of CO2-fixing autotrophs to P fertiliser depended on the irrigation management method. The redundancy analysis revealed that 54% of the variation in the functional marker gene abundances could be explained by the irrigation method, P fertiliser and the Olsen-P content; however, the rhizosphere effect did not have any significant influence. P fertiliser application under CF was more beneficial in improving the abundance of CO2-fixing autotrophs compared to the AWD treatment; thus, it is an ideal irrigation management method to increase soil carbon fixation. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Lab and Field Warming Similarly Advance Germination Date and Limit Germination Rate for High and Low Elevation Provenances of Two Widespread Subalpine Conifers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kueppers, Lara; Faist, Akasha; Ferrenberg, Scott

Accurately predicting upslope shifts in subalpine tree ranges with warming requires understanding how future forest populations will be affected by climate change, as these are the seed sources for new tree line and alpine populations. Early life history stages are particularly sensitive to climate and are also influenced by genetic variation among populations. Here, we tested the climate sensitivity of germination and initial development for two widely distributed subalpine conifers, using controlled-environment growth chambers with one temperature regime from subalpine forest in the Colorado Rocky Mountains and one 5 °C warmer, and two soil moisture levels. We also tracked germinationmore » rate and timing, rate of seedling development, and seedling morphology for two seed provenances separated by ~300 m elevation. Warming advanced germination timing and initial seedling development by a total of ~2 weeks, advances comparable to mean differences between provenances. Advances were similar for both provenances and species; however, warming reduced the overall germination rate, as did low soil moisture, only for Picea engelmannii. A three-year field warming and watering experiment planted with the same species and provenances yielded responses qualitatively consistent with the lab trials. Altogether these experiments indicate that in a warmer, drier climate, P. engelmannii germination, and thus regeneration, could decline, which could lead to declining subalpine forest populations, while Pinus flexilis forest populations could remain robust as a seed source for upslope range shifts.« less
Controls of growth phenology vary in seedlings of three, co-occurring ecologically distinct northern conifers.

PubMed

Green, D Scott

2007-08-01

The objective of this study was to investigate the effects of temperature and seed-source elevation on height-growth phenology of three co-occurring and ecologically distinct northern conifers (Pinus contorta Dougl. ex Loud. var. latifolia (lodgepole pine), Picea glauca (Moench) Voss x Picea engelmannii Parry ex Engelm. (interior spruce) and Abies lasiocarpa (Hook.) Nutt. (subalpine fir)). Seed from populations of the three indigenous and co-occurring species was collected across an elevational transect on the southwestern slope of McBride Peak, near Prince George, BC. Collection sites were at elevations of 750 to 1850 m, the latter being close to the tree line. In 2003, seeds were germinated and seedlings raised under favorable growing conditions in a temperature-controlled glasshouse. In 2004, seedlings of each population were grown in natural daylengths at a location within 50 km of the seed collection site both in a temperature-controlled glasshouse and at a nearby field site, and height growth was recorded twice a week throughout the growing season. Species differed in both the date and the accumulated heat sum above 5 degrees C for the initiation and cessation of shoot extension. Growth durations (which integrate growth initiation and growth cessation) were more similar among species in the field than in the glasshouse. This suggests that different mechanisms of phenological control among co-occurring species can result in adaptive "equivalence" under a particular set of climatic conditions.
Lab and Field Warming Similarly Advance Germination Date and Limit Germination Rate for High and Low Elevation Provenances of Two Widespread Subalpine Conifers

DOE PAGES

Kueppers, Lara; Faist, Akasha; Ferrenberg, Scott; ...

2017-11-11

Accurately predicting upslope shifts in subalpine tree ranges with warming requires understanding how future forest populations will be affected by climate change, as these are the seed sources for new tree line and alpine populations. Early life history stages are particularly sensitive to climate and are also influenced by genetic variation among populations. Here, we tested the climate sensitivity of germination and initial development for two widely distributed subalpine conifers, using controlled-environment growth chambers with one temperature regime from subalpine forest in the Colorado Rocky Mountains and one 5 °C warmer, and two soil moisture levels. We also tracked germinationmore » rate and timing, rate of seedling development, and seedling morphology for two seed provenances separated by ~300 m elevation. Warming advanced germination timing and initial seedling development by a total of ~2 weeks, advances comparable to mean differences between provenances. Advances were similar for both provenances and species; however, warming reduced the overall germination rate, as did low soil moisture, only for Picea engelmannii. A three-year field warming and watering experiment planted with the same species and provenances yielded responses qualitatively consistent with the lab trials. Altogether these experiments indicate that in a warmer, drier climate, P. engelmannii germination, and thus regeneration, could decline, which could lead to declining subalpine forest populations, while Pinus flexilis forest populations could remain robust as a seed source for upslope range shifts.« less
The effects of ocean acidification and a carbon dioxide capture and storage leak on the early life stages of the marine mussel Perna perna (Linneaus, 1758) and metal bioavailability.

PubMed

Szalaj, D; De Orte, M R; Goulding, T A; Medeiros, I D; DelValls, T A; Cesar, A

2017-01-01

The study assesses the effects of carbon dioxide capture and storage (CCS) leaks and ocean acidification (OA) on the metal bioavailability and reproduction of the mytilid Perna perna. In laboratory-scale experiments, CCS leakage scenarios (pH 7.0, 6.5, 6.0) and one OA (pH 7.6) scenario were tested using metal-contaminated sediment elutriates and seawater from Santos Bay. The OA treatment did not have an effect on fertilisation, while significant effects were observed in larval-development bioassays where only 16 to 27 % of larva developed normally. In treatments that simulated CO 2 leaks, when compared with control, fertilisation success gradually decreased and no larva developed to the D-shaped stage. A fall in pH increased the bioavailability of metals to marine mussels. Larva shell size was significantly affected by both elutriates when compared with seawater; moreover, a significant difference occurred at pH 6.5 between elutriates in the fertilisation bioassay.
Biochar, compost and biochar-compost blend as options to recover nutrients and sequester carbon.

PubMed

Oldfield, Thomas L; Sikirica, Nataša; Mondini, Claudio; López, Guadalupe; Kuikman, Peter J; Holden, Nicholas M

2018-07-15

This work assessed the potential environmental impact of recycling organic materials in agriculture via pyrolysis (biochar) and composting (compost), as well its combination (biochar-compost blend) versus business-as-usual represented by mineral fertiliser. Life cycle assessment methodology was applied using data sourced from experiments (FP7 project Fertiplus) in three countries (Spain, Italy and Belgium), and considering three environmental impact categories, (i) global warming; (ii) acidification and (iii) eutrophication. The novelty of this analysis is the inclusion of the biochar-compost blend with a focus on multiple European countries, and the inclusion of the acidification and eutrophication impact categories. Biochar, compost and biochar-compost blend all resulted in lower environmental impacts than mineral fertiliser from a systems perspective. Regional differences were found between biochar, compost and biochar-compost blend. The biochar-compost blend offered benefits related to available nutrients and sequestered C. It also produced yields of similar magnitude to mineral fertiliser, which makes its acceptance by farmers more likely whilst reducing environmental impacts. However, careful consideration of feedstock is required. Copyright © 2018 Elsevier Ltd. All rights reserved.
Stabilisation of microalgae: Iodine mobilisation under aerobic and anaerobic conditions.

PubMed

Han, Wei; Clarke, William; Pratt, Steven

2015-10-01

Mobilisation of iodine during microalgae stabilisation was investigated, with the view of assessing the potential of stabilised microalgae as an iodine-rich fertiliser. An iodine-rich waste microalgae (0.35 ± 0.05 mg I g(-1) VS(added)) was stabilised under aerobic and anaerobic conditions. Iodine mobilisation was linearly correlated with carbon emission, indicating iodine was in the form of organoiodine. Comparison between iodine and nitrogen mobilisation relative to carbon emission indicated that these elements were, at least in part, housed separately within the cells. After stabilisation, there were 0.22 ± 0.05 and 0.19 ± 0.01 mg g(-1) VS(added) iodine remaining in the solid in the aerobic and anaerobic processed material respectively, meaning 38 ± 5.0% (aerobic) and 50 ± 8.6% (anaerobic) of the iodine were mobilised, and consequently lost from the material. The iodine content of the stabilised material is comparable to the iodine content of some seaweed fertilisers, and potentially satisfies an efficient I-fertilisation dose. Copyright © 2015 Elsevier Ltd. All rights reserved.
Experience of mating rivals causes males to modulate sperm transfer in the fly Drosophila pseudoobscura.

PubMed

Price, Tom A R; Lizé, Anne; Marcello, Marco; Bretman, Amanda

2012-12-01

Male responses to risk of sperm competition play an important role in sexual selection, sexual conflict, and the evolution of mating systems. Such responses can combine behavioural and physiological processes, and can be mediated through different components of the ejaculate such as sperm numbers and seminal proteins. An additional level of ejaculate complexity is sperm heteromorphism, with the inclusion of non-fertilising parasperm in the ejaculate. We now test the response to rivals in a sperm heteromorphic species, Drosophila pseudoobscura, measuring the behavioural response and sperm transfer and, crucially, relating these to short-term fitness. Males respond to exposure to conspecific rivals by increasing mating duration, but do not respond to heterospecific rivals. In addition, after exposure to a conspecific rival, males increased the transfer of fertilising eusperm, but not non-fertilising parasperm. Males exposed to a conspecific rival also achieve higher offspring production. This suggests that the evolution of parasperm in flies was not driven by sperm competition and adds to the increasing evidence that males can make extremely sophisticated responses to mating competition. Copyright © 2012. Published by Elsevier Ltd.
Dermatological Manifestations in Patients Undergoing In Vitro Fertilisation: A Prospective Study.

PubMed

Sood, Aradhana; Sahu, Suvash; Karunakaran, Sandeep; Joshi, Rajneesh K; Raman, Deep Kumar

Changing sociodemographic patterns with an increase in the age of childbirth have affected fertility rates worldwide. With advancing reproductive medicine, assisted reproductive techniques (ARTs) are becoming common. While dermatological manifestations in normal pregnancies have been well documented, there is a paucity of data regarding cutaneous manifestations in patients undergoing ART. The objectives of our study were to estimate the incidence and types of dermatological manifestations in patients undergoing in vitro fertilisation (IVF) and to study their associations with age, type of infertility, and outcome of the procedure. A prospective cohort of 200 patients undergoing IVF in a tertiary care centre was observed for occurrence of any dermatological manifestations from initiation of the IVF protocol to the outcome of the procedure at 3 weeks after embryo transfer. Dermatological manifestations were seen in 27% of the study group, with urticaria being the most common cutaneous finding seen in 13.5%, followed by acneform eruptions (3%). Twenty-six (96.3%) of patients who manifested with urticaria were on progesterone. No statistically significant association was found between the occurrence of dermatological manifestations and the outcome of IVF, type of infertility, history of ART, and ovum donation in our study. Association between the age of the patient and the outcome of IVF cycle was statistically significant. Dermatological manifestations are seen in almost one-quarter of patients undergoing IVF, with progesterone-induced urticaria being the most common. Occurrence of cutaneous manifestations has no significant association with the outcome of IVF.
Impacts of peatland restoration on dissolved carbon loss from eroded upland peatlands in the UK

NASA Astrophysics Data System (ADS)

Evans, M.; Stimson, A.; Allott, T. E. H. A.; Holland, N.

2012-04-01

Upland blanket peatlands in the UK are severely degraded by extensive gully erosion. Large areas have experienced complete vegetation loss. In the last decade landscape scale approaches to the restoration of eroded and bare peat have been developed in the Peak District National Park in northern England. Bare peat is re-vegetated with a nurse crop of grasses established by the aerial application of lime, seed, and fertiliser. The approach has successfully re-vegetated large areas of eroded bog a nd has been shown to dramatically reduce particulate carbon losses in runoff. The impacts of the treatment on water quality and dissolved carbon loss have not previously been fully assessed. This paper reports results from a small catchment study assessing the impacts of restoration practice in the Peak District. Data from five small catchments are presented one re-vegetated, one intact and three eroded/bare catchments. Bi-weekly water samples have been taken from the catchments between January 2011 and February 2012 and during July 2012 two of the bare sites were treated with lime, seed, and fertiliser. The data show that there are significant spikes in nutrient flux post treatment and marked effects on dissolved carbon which include initial spikes in in DOC concentration but longer term reductions in DOC concentration. Monitoring is ongoing at these sites but the evidence to date points to at least a short term benefit in DOC flux reduction from this form of peatland restoration.
Photosynthetic Physiological Response of Radix Isatidis (Isatis indigotica Fort.) Seedlings to Nicosulfuron

PubMed Central

Ning, Na; Wen, Yinyuan; Dong, Shuqi; Yin, Meiqiang; Guo, Meijun; Wang, Binqiang; Feng, Lei; Guo, Pingyi

2014-01-01

Radix Isatidis (Isatis indigotica Fort.) is one of the most important traditional Chinese medicine plants. However, there is no suitable herbicide used for weed control in Radix Isatidis field during postemergence stage. To explore the safety of sulfonylurea herbicide nicosulfuron on Radix Isatidis (Isatis indigotica Fort.) seedlings and the photosynthetic physiological response of the plant to the herbicide, biological mass, leaf area, photosynthetic pigment content, photosynthetic rate, chlorophyll fluorescence characteristics, and P700 parameters of Radix Isatidis seedlings were analyzed 10 d after nicosulfuron treatment at 5th leaf stage in this greenhouse research. The results showed that biological mass, total chlorophyll, chlorophyll a, and carotenoids content, photosynthetic rate, stomatal conductance, PS II maximum quantum yield, PS II effective quantum yield, PS II electron transport rate, photochemical quenching, maximal P700 change, photochemical quantum yield of PS I, and PS I electron transport rate decreased with increasing herbicide concentrations, whereas initial fluorescence, quantum yield of non-regulated energy dissipation in PS II and quantum yield of non-photochemical energy dissipation due to acceptor side limitation in PS I increased. It suggests that nicosulfuron ≥1 mg L−1 causes the damage of chloroplast, PS II and PS I structure. Electron transport limitations in PS I receptor side, and blocked dark reaction process may be the main cause of the significantly inhibited growth and decreased photosynthetic rate of Radix Isatidis seedlings. PMID:25165819
Catechol, a major component of smoke, influences primary root growth and root hair elongation through reactive oxygen species-mediated redox signaling.

PubMed

Wang, Ming; Schoettner, Matthias; Xu, Shuqing; Paetz, Christian; Wilde, Julia; Baldwin, Ian T; Groten, Karin

2017-03-01

Nicotiana attenuata germinates from long-lived seedbanks in native soils after fires. Although smoke signals have been known to break seed dormancy, whether they also affect seedling establishment and root development remains unclear. In order to test this, seedlings were treated with smoke solutions. Seedlings responded in a dose-dependent manner with significantly increased primary root lengths, due mainly to longitudinal cell elongation, increased numbers of lateral roots and impaired root hair development. Bioassay-driven fractionations and NMR were used to identify catechol as the main active compound for the smoke-induced root phenotype. The transcriptome analysis revealed that mainly genes related to auxin biosynthesis and redox homeostasis were altered after catechol treatment. However, histochemical analyses of reactive oxygen species (ROS) and the inability of auxin applications to rescue the phenotype clearly indicated that highly localized changes in the root's redox-status, rather than in levels of auxin, are the primary effector. Moreover, H 2 O 2 application rescued the phenotype in a dose-dependent manner. Chemical cues in smoke not only initiate seed germination, but also influence seedling root growth; understanding how these cues work provides new insights into the molecular mechanisms by which plants adapt to post-fire environments. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.
In vitro propagation of northern red oak (Quercus rubra L.)

Treesearch

G. Vengadesan; Paula M. Pijut

2009-01-01

In vitro propagation of northern red oak (Quercus rubra) shoots was successful from cotyledonary node explants excised from 8-wk-old in vitro grown seedlings. Initially, four shoots per explant were obtained on Murashige and Skoog (MS) medium supplemented with 4.4 µM 6-benzylaminopurine (BA), 0.45 ...
Recognizing all-aged hemlock forests

Treesearch

Orie L. Loucks; James Nighswander

2000-01-01

Eastern hemlock (Tsuga canadensis (L.) Carr.) occurs in old-growth stands sometimes over 400 years old, throughout its principal range from Nova Scotia to Wisconsin. Studies based on aging as well as diameter distributions indicate a stand structure often dominated by an initial multi-decade post-disturbance pulse of seedling establishment, followed...
Predicting the effects of hardwood competition on red pine seedling growth

Treesearch

Alan S. White; Katherine J. Elliott

1992-01-01

Pin cherry (Prunus pensylvanica L.f.) and striped maple (Acer pensylvanicum L.) are potentially important competitors of red pine (Pinus resinosa Ait) planted on recently clear-cut hardwood sites. By experimentally manipulating initial competitor densities on 2.0-m2 plots, we were able to...
Field and laboratory root growth and development of Lesquerella germplasm

USDA-ARS?s Scientific Manuscript database

Lesquerella roots have not been fully characterized as compared to other crop species. There is initial information gathered on root trait variation in young seedling grown in laboratory settings but studies to determine if the results can be extrapolated in field grown plants are lacking. We report...
Identification of Vigor Related Transcripts in Beta vulgaris When Germinated Under Abiotic Stress

USDA-ARS?s Scientific Manuscript database

Germination is the first opportunity to evaluate vigor for beet breeders. The initial condition a germinating seed encounters affects the speed and success of germination, the amount of stored energy reserves to withstand future stress, and the overall ability of the seedling to flourish. However, s...
Blue and Valley Oak Seedling Establishment on California's Hardwood Rangelands

Treesearch

Theodore E. Adams Jr.; Peter B. Sands; William H. Weitkamp; Neil K. McDougald

1991-01-01

Factors contributing to poor establishment of blue oak (Quercus douglasii) and valley oak (Q. lobata) in California oak-grassland savannas were studied in a series of acorn seeding experiments initiated in 1985. Exclusion of large herbivores permitted examination of herbaceous interference and small mammal and insect depredation....

Effect of heavy metals on seed germination and seedling growth of common ragweed and roadside ground cover legumes.

PubMed

Bae, Jichul; Benoit, Diane L; Watson, Alan K

2016-06-01

In southern Québec, supplement roadside ground covers (i.e. Trifolium spp.) struggle to establish near edges of major roads and thus fail to assist turf recruitment. It creates empty niches vulnerable to weed establishment such as common ragweed (Ambrosia artemisiifolia). We hypothesized that heavy metal stresses may drive such species shifts along roadside edges. A growth chamber experiment was conducted to assess effects of metals (Zn, Pb, Ni, Cu, and Cd) on germination and seedling behaviors of roadside weed (A. artemisiifolia) and ground cover legumes (Coronilla varia, Lotus corniculatus, and Trifolium arvense). All metals inhibited T. arvense germination, but the effect was least on A. artemisiifolia. Low levels of Pb and Ni promoted germination initiation of A. artemisiifolia. Germination of L. corniculatus was not affected by Zn, Pb, and Ni, but inhibited by Cu and Cd. Germination of C. varia was decreased by Ni, Cu, and Cd and delayed by Zn and Pb. Metal additions hindered seedling growth of all test species, and the inhibitory effect on the belowground growth was greater than on the aboveground growth. Seedling mortality was lowest in A. artemisiifolia but highest in T. arvense when exposed to the metal treatments. L. corniculatus and C. varia seedlings survived when subjected to high levels of Zn, Pb, and Cd. In conclusion, the successful establishment of A. artemisiifolia along roadside edges can be associated with its greater tolerance of heavy metals. The findings also revealed that L. corniculatus is a potential candidate for supplement ground cover in metal-contaminated roadside edges in southern Québec, especially sites contaminated with Zn and Pb. Copyright © 2015 Elsevier Ltd. All rights reserved.
Effects of soil type and light on height growth, biomass partitioning, and nitrogen dynamics on 22 species of tropical dry forest tree seedlings: Comparisons between legumes and nonlegumes.

PubMed

Smith-Martin, Christina M; Gei, Maria G; Bergstrom, Ellie; Becklund, Kristen K; Becknell, Justin M; Waring, Bonnie G; Werden, Leland K; Powers, Jennifer S

2017-03-01

The seedling stage is particularly vulnerable to resource limitation, with potential consequences for community composition. We investigated how light and soil variation affected early growth, biomass partitioning, morphology, and physiology of 22 tree species common in tropical dry forest, including eight legumes. Our hypothesis was that legume seedlings are better at taking advantage of increased resource availability, which contributes to their successful regeneration in tropical dry forests. We grew seedlings in a full-factorial design under two light levels in two soil types that differed in nutrient concentrations and soil moisture. We measured height biweekly and, at final harvest, biomass partitioning, internode segments, leaf carbon, nitrogen, δ 13 C, and δ 15 N. Legumes initially grew taller and maintained that height advantage over time under all experimental conditions. Legumes also had the highest final total biomass and water-use efficiency in the high-light and high-resource soil. For nitrogen-fixing legumes, the amount of nitrogen derived from fixation was highest in the richer soil. Although seed mass tended to be larger in legumes, seed size alone did not account for all the differences between legumes and nonlegumes. Both belowground and aboveground resources were limiting to early seedling growth and function. Legumes may have a different regeneration niche, in that they germinate rapidly and grow taller than other species immediately after germination, maximizing their performance when light and belowground resources are readily available, and potentially permitting them to take advantage of high light, nutrient, and water availability at the beginning of the wet season. © 2017 Botanical Society of America.
CO2-induced photosynthetic and stoichiometric responses to phosphorus limitation

NASA Astrophysics Data System (ADS)

de Boer, Hugo; di Lallo, Giacomo; van Dijk, Jerry

2017-04-01

Carbon fertilisation from rising atmospheric CO2 concentrations increases the productivity of plants globally. Meanwhile, the global cycles of Nitrogen (N) and Phosphorus (P) are also altered due to anthropogenic emissions. In general, the additional supply of N is expected to exceed that of P, leading to an increase in P limitation in natural ecosystems. Although the direct carbon fertilisation effect and the interaction with available N is relatively well understood, it remains uncertain how carbon fertilisation is confounded by the availability of P. It is hypothesised that (i) the photosynthetic P-use efficiency increases at elevated CO2 owing to a direct increase in photosynthesis and (ii) the photosynthetic maximum carboxylation rate (Vcmax) and electron transport rate (Jmax) are down-regulated in response to a combination of elevated CO2 and P-limitation via a coordinated reduction of leaf N and P content per unit leaf area. In this study we examined the hypothesised effects of P limitation and CO2 fertilisation on the photosynthetic and stoichiometric responses of three plant species: Holcus lanatus (C3 grass), Panicum miliaceum (C4 grass) and Solanum dulcamara (C3 herb). Individuals of these species were grown at sub-ambient (150 ppm), modern (450 ppm) and elevated CO2 concentrations (800 ppm) and exposed to an N:P treatment consisting of either severe nitrogen limitation at an N:P ratio of 1:1, or severe P limitation at an N:P ratio of 45:1, with a similar supply rate of N. Our results show significant effects of growth CO2 and P supply on Vcmax and Jmax, as well as the whole-plant biomass at the point of harvest. Interaction effects between growth CO2 and P supply were observed for the light-saturated photosynthesis rate, stomatal conductance, leaf P content, and the N:P ratio of the leaf. No significant change in the leaf N content was observed across treatments. These results suggest that limited availability of P constrains the biochemical potential for plants to up-regulate Vcmax and Jmax. This effect is most prominently expressed at low CO2 growth conditions, which induce strong up-regulation of Vcmax and Jmax when P is not limiting. Conversely, the down-regulation of Vcmax and Jmax at elevated CO2 is more pronounced when P is limiting. Hence, the combined effects of rising CO2 and additional P limitation may result in additional down-regulation of Vcmax and Jmax and a subsequent waning of the CO2 fertilisation effect. These results highlight the need to consider P limitation in global vegetation models when studying carbon fertilisation effects.
Ultrastructure of meristem and root cap of pea seedlings under spaceflight conditions

NASA Technical Reports Server (NTRS)

Sytnyk, K. M.; Kordyum, E. L.; Bilyavska, N. O.; Tarasenko, V. O.

1983-01-01

Data of electron microscopic analysis of meristem and root cap of pea seedlings grown aboard the Salyut-6 orbital research station in the Oazis apparatus and in the laboratory are presented. The main morphological and anatomical characteristics of the test and control plants are shown to be similar. At the same time, some differences are found in the structural and functional organization of the experimental cells as compared to the controls. They concern first of all the plastic apparatus, mitochondria and Golgi apparatus. It is assumed that cell function for certain periods of weightlessness on the whole ensures execution of the cytodifferentiation programs genetically determined on the Earth. Biochemical and physiological processes vary rather markedly due to lack of initially rigorous determination.
Effects of flooding regime and seedling treatment on early survival and growth of nuttall oak

USGS Publications Warehouse

Burkett, V.R.; Draugelis-Dale, R.O.; Williams, H.M.; Schoenholtz, S.H.

2005-01-01

Effects of flooding on survival and growth of three different types of Nuttall oak (Quercus texana Buckl.) seedlings were observed at the end of third and fifth growing seasons at Yazoo National Wildlife Refuge, Mississippi, U.S.A. Three types of seedlings were planted in January 1995 in a split-plot design, with four replications at each of two elevations on floodprone, former cropland in Sharkey clay soil. The lower of the two planting elevations was inundated for 21 days during the first growing season, whereas the higher elevation did not flood during the 5-year period of this study. The three types of 1-0 seedlings were bareroot seedlings, seedlings grown in containers (3.8 ?? 21a??cm plastic seedling cones), and container-grown seedlings inoculated with vegetative mycelia of Pisolithus tinctorius (Pers.) Coker. Survival of all the three seedling types was greatest at the lower, intermittently flooded elevation, indicating that drought and related effects on plant competition were more limiting to seedling survival than flooding. At the lower elevation, survival of mycorrhizal-inoculated container seedlings was greater than that of noninoculated container seedlings. Survival among bareroot seedlings and inoculated container seedlings was not significantly different at either elevation. At the higher, nonflooded elevation, however, bareroot seedling survival was greater than the survival of container seedlings without inoculation. Differences were significant among the inoculated and the noninoculated container seedlings, with higher survival of inoculated seedlings at both elevations, though differences were only significant in year 3. At the end of the fifth year, height of bareroot seedlings was significantly greater than the heights of both types of container-grown seedlings at both planting elevations. Because seedlings grown in the plastic seedlings cones did not survive better than the bareroot seedlings at either planting elevation, the bareroot stock appear to be the economically superior choice for regeneration in Sharkey soil.
The Earth Observation Technology Cluster

NASA Astrophysics Data System (ADS)

Aplin, P.; Boyd, D. S.; Danson, F. M.; Donoghue, D. N. M.; Ferrier, G.; Galiatsatos, N.; Marsh, A.; Pope, A.; Ramirez, F. A.; Tate, N. J.

2012-07-01

The Earth Observation Technology Cluster is a knowledge exchange initiative, promoting development, understanding and communication about innovative technology used in remote sensing of the terrestrial or land surface. This initiative provides an opportunity for presentation of novel developments from, and cross-fertilisation of ideas between, the many and diverse members of the terrestrial remote sensing community. The Earth Observation Technology Cluster involves a range of knowledge exchange activities, including organisation of technical events, delivery of educational materials, publication of scientific findings and development of a coherent terrestrial EO community. The initiative as a whole covers the full range of remote sensing operation, from new platform and sensor development, through image retrieval and analysis, to data applications and environmental modelling. However, certain topical and strategic themes have been selected for detailed investigation: (1) Unpiloted Aerial Vehicles, (2) Terrestrial Laser Scanning, (3) Field-Based Fourier Transform Infra-Red Spectroscopy, (4) Hypertemporal Image Analysis, and (5) Circumpolar and Cryospheric Application. This paper presents general activities and achievements of the Earth Observation Technology Cluster, and reviews state-of-the-art developments in the five specific thematic areas.
The effects of Vexar® seedling protectors on the growth and development of lodgepole pine roots

USGS Publications Warehouse

Engeman, Richard M.; Anthony, R. Michael; Krupa, Heather W.; Evans, James

1997-01-01

The effects on the growth and development of lodgepole pine roots from the Vexar® tubes used to protect seedlings from pocket gopher damage were studied in the Targhee National Forest, Idaho and the Deschutes National Forest, Oregon. At each site, Vexar-protected and unprotected seedlings, with and without above-ground gopher damage were examined after six growing seasons for root deformities and growth. Undamaged seedlings exhibited greater growth, reflecting the importance of non-lethal gopher damage as a deterrent to tree growth. Protected seedlings with similar damage history as unprotected seedlings had greater root depth than unprotected seedlings, although unprotected seedlings with no above-ground damage generally had the greatest root weight. In general, the percent of seedlings with root deformities was greater for the unprotected seedlings than for the Vexar-protectd seedlings, although this could be largely due to the greater care required to plant protected seedlings. Acute deformities were more common for unprotected seedlings, whereas root deformities with less severe bending were more common for protected seedlings. The incidence of crossed roots was similar for protected and unprotected seedlings on the Deschutes site, where enough occurrences of this deformity permitted analyses. Protected seedlings were similar in root abundance, root distribution, root size and vigor to the unprotected seedlings, with some indication from the Deshutes study site that root distribution was improved with Vexar protection.
Farmer attitudes and perceptions to the re-use of fertiliser products from resource-oriented sanitation systems - The case of Vellore, South India.

PubMed

Simha, Prithvi; Lalander, Cecilia; Vinnerås, Björn; Ganesapillai, M

2017-03-01

Relatively little research has been conducted to date on farmer attitudes towards the use of fertilisers from resource-oriented sanitation systems. This study employed a psycho-sociological approach to identify factors that encourage, or discourage, negative and positive attitudes to human waste recycling among farmers in southern India. A survey involving face-to-face interviews was performed with 120 randomly sampled farmers, taking into account the following factors: gender, age, religion, caste, type of farming, farm size, annual income and farming history. Variations in variables (χ 2 and ANOVA) were considered statistically significant if p-value was <0.05. When asked whether they thought human wastes could be used as fertiliser, of the farmers who expressed an opinion 59% were positive to re-use of urine and 46% to re-use of human faeces. Farmers in Vellore appeared to display what we term, a 'not-in-my-circle' syndrome, as they would prefer their neighbours to use human urine rather than their friends, family and colleagues. The main factors that motivated farmers to respond positively to re-use of urine were improved soil quality and potential cost savings from reduced use of chemical fertilisers. Fear of crop die-off, fear of being ridiculed and uncertainty over consumer marketplace behaviour were significant factors among farmers with a negative attitude. Furthermore, the survey responses indicated that besides socio-demographic factors, other factors such as 'trust' might have to be taken into consideration when planning and implementing nutrient recycling programmes. Early dialogue, continuous interaction and integration of user stakeholders (producers and consumers) in conceptualisation, design and implementation of nutrient recycling programmes are essential to ensure future success and wider adoption. Copyright © 2017 Elsevier B.V. All rights reserved.
Relationships between rabbit semen characteristics and fertilising ability after insemination.

PubMed

Theau-Clément, M; Ailloud, E; Sanchez, A; Saleil, G; Brun, J M

2016-03-01

This study aimed to analyse the relationship between rabbit semen characteristics and semen fertilising ability after insemination, which is generally found to be weak. Our hypothesis was that using high semen dilutions (1 : 19), non-oestrus-stimulated does, and homospermic inseminations would make it easier to predict semen fertilising ability. Semen characteristics were evaluated on 275 ejaculates of 128 INRA1001 bucks, distributed into five successive batches. A total of 1970 inseminations were performed. The continuous semen variables were subdivided into three classes of similar size to account for any non-linear relationship between semen characteristics and fertilising ability. Mass motility was divided into two classes according to the presence or absence of waves under microscope observation. Libido, the presence or absence of gel, volume, percentage of progressive sperms, curvilinear velocity, beat frequency of the flagellum, and straightness and linearity of sperm movement did not affect fertility, prolificacy or productivity. It was confirmed that mass motility, estimated by visual observation under the microscope, significantly influenced fertility as well as the percentage of motile and of rapid sperms, and the amplitude of lateral head displacement, estimated by a computer-assisted semen analysis system. To a lesser extent, the percentage of motile cells and of rapid cells significantly influenced prolificacy. Consequently, mass motility and the percentage of motile cells significantly influenced rabbit doe productivity (+1 live births/AI when the semen showed at least a beginning of wave movement, or when the percentage of motile cells was >84%). Interestingly, a gain of 1.5 rabbits was observed when the percentage of rapid cells changed from 64% to 79%, whereas productivity significantly dropped beyond 83% of rapid cells, reflecting a non-linear relationship.
Case reports to suggest an algorithm for management of total fertilisation failure prior to use of donor gametes.

PubMed

Nicopoullos, James D M; Whitney, E; Wells, V; Batha, S; Faris, R; Abdalla, H

2015-11-01

Total fertilisation failure (TFF), even with intracytoplasmic sperm injection (ICSI), occurs in approximately 3 % of cycles, can be recurrent and the exact cause is difficult to elucidate. Differentiation between oocyte and sperm-related cause of TFF is possible using mouse oocyte-activation techniques, but is not an option within most clinical settings. Therefore, the management of these couples is clinically driven, and the endpoint, if recurrent, is often the use of donor gametes. However, with the invariable lack of a definitive cause of TFF, any decision between the use of donor sperm or oocytes remains an emotive one. We present two case reports demonstrating the importance of appropriate investigation, activation techniques (mechanical and chemical) and clinical management options to develop a clinical algorithm prior to the use of donor gametes. This study is composed of two case reports of assisted reproduction investigation and treatment within an assisted conception unit for couples with recurrent total fertilisation failure. Using appropriate investigation (endocrine, urological and embryological) and treatments (ICSI, IMSI, oocyte-activation techniques), a fertilisation rate of 48 % was achieved in two cycles in couples following a total of nine previous cycles (and 200 previously collected eggs) with TFF. Oocyte activation requires the triggering of intracellular calcium oscillations by the release of a sperm-specific factor (phospholipase C zeta (PLCζ)) into the oocyte cytoplasm. Although, PLCζ deficiencies have been demonstrated as putative causes of failed activation, impaired oocyte responsiveness may also be a factor. The use of donor gametes is often recommended and is often the required endpoint of treatment. However, these reports outline a clinical algorithm that potentially offers success without donation, and also offers a systematic approach to help decide whether donor oocytes or sperm should be recommended.
Alkylation of sperm DNA is associated with male factor infertility and a reduction in the proportion of oocytes fertilised during assisted reproduction.

PubMed

Stocks, S J; Agius, R M; Cooley, N; Harrison, K L; Brison, D R; Horne, G; Gibbs, A; Povey, A C

2010-04-30

Approximately one-third of IVF cases in the UK are attributed to male factor infertility and in the majority of cases the origin of male infertility is unknown. The integrity of sperm DNA is important both for the success of assisted reproduction and the implications for the off-spring. One type of DNA damage that has not been investigated with respect to fertility outcomes is the adduct N7-methyldeoxyguanosine (N7-MedG), a biomarker for exposure to alkylating agents. A prospective cohort of couples attending for IVF had their N7-MedG levels in sperm measured using an immunoslot blot technique to examine whether sperm N7-MedG levels are associated with male factor infertility, semen quality measures or assisted reproduction outcomes. Sufficient DNA for analysis was obtained from 67/97 couples and N7-MedG was detected in 94% of sperm samples analysed. Men diagnosed with male factor infertility had significantly higher mean levels of N7-MedG in their sperm DNA (P=0.03). Logistic regression analysis showed that N7-MedG levels were significantly negatively associated with the proportion of oocytes successfully fertilised irrespective of the method of fertilisation used (IVF or intra-cytoplasmic sperm injection; ICSI, P<0.001). Therefore exposure to DNA alkylating agents is significantly associated with male infertility and the proportion of oocytes fertilised during assisted reproduction. Reducing such exposure may improve male fertility but further work is required to determine the relative importance of exogenous and endogenous sources of exposure. Copyright 2010 Elsevier B.V. All rights reserved.
Factors influencing tissue nitrate concentration in field-grown wild rocket (Diplotaxis tenuifolia) in southern England.

PubMed

Weightman, R M; Huckle, A J; Roques, S E; Ginsburg, D; Dyer, C J

2012-01-01

Wild rocket (Diplotaxis tenuifolia) is a leafy vegetable known for its high tissue nitrate concentration (TNC) which can exceed the limits set in the relevant European legislation designed to protect human health. The aim of this work was to understand the factors influencing TNC and to develop best practice guidelines to growers. Commercial crops of field-grown wild rocket were studied over two seasons. In 2010, ten separate crops were sampled representing a range of soil types and time periods during the summer. Two fields sampled using a 'W'- or 'X'-shaped sampling pattern demonstrated that 10 incremental samples bulked to make 1 kg of fresh material could be used to provide an adequate sample for determination of TNC in the wild rocket crop, as is the case for other leafy vegetables. Of eight commercial crops sampled in 2010 with an average nitrogen (N) fertiliser application of 104 kg N ha(-1), two exceeded the limit of 6000 mg NO3(-) kg(-1) set in the legislation. In 2011, six N response experiments were carried out, and only two sites showed a significant yield response to N fertiliser. The reason for the lack of response at the other sites was principally due to high levels of soil mineral N prior to drilling, meaning the crops' requirement for N was satisfied without additional fertiliser N. In the experimental situation at an N fertiliser application rate of 120 kg N ha(-1), 50% of crops would have exceeded the 6000 mg NO3(-) kg(-1) limit. In both seasons, low radiation levels in the 5 days prior to harvest were shown to increase TNC, although the relationship was also influenced by N supply. Strategies for optimising N nutrition of field-grown wild rocket are discussed.
Effect of residue combinations on plant uptake of nutrients and potentially toxic elements.

PubMed

Brännvall, Evelina; Nilsson, Malin; Sjöblom, Rolf; Skoglund, Nils; Kumpiene, Jurate

2014-01-01

The aim of the plant pot experiment was to evaluate potential environmental impacts of combined industrial residues to be used as soil fertilisers by analysing i) element availability in fly ash and biosolids mixed with soil both individual and in combination, ii) changes in element phytoavailability in soil fertilised with these materials and iii) impact of the fertilisers on plant growth and element uptake. Plant pot experiments were carried out, using soil to which fresh residue mixtures had been added. The results showed that element availability did not correlate with plant growth in the fertilised soil with. The largest concentrations of K (3534 mg/l), Mg (184 mg/l), P (1.8 mg/l), S (760 mg/l), Cu (0.39 mg/l) and Zn (0.58 mg/l) in soil pore water were found in the soil mixture with biosolids and MSWI fly ashes; however plants did not grow at all in mixtures containing the latter, most likely due to the high concentration of chlorides (82 g/kg in the leachate) in this ash. It is known that high salinity of soil can reduce germination by e.g. limiting water absorption by the seeds. The concentrations of As, Cd and Pb in grown plants were negligible in most of the soils and were below the instrument detection limit values. The proportions of biofuel fly ash and biosolids can be adjusted in order to balance the amount and availability of macronutrients, while the possible increase of potentially toxic elements in biomass is negligible seeing as the plant uptake of such elements was low. Copyright © 2013 Elsevier Ltd. All rights reserved.
Deployment of deer-resistant western redcedar (Thuja plicata)

Treesearch

John Russell

2008-01-01

Protecting planted western redcedar (Thuja plicata) seedlings from deer browse in the Pacific Northwest and British Columbia is estimated to cost up to CAN$ 25 million annually. Recent studies linking deer browse and needle monoterpenes has resulted in the initiation of a breeding program for deer-resistant western redcedar at Cowichan Lake Research...
Accuracy of regeneration surveys in New England northern hardwoods

Treesearch

William B. Leak

2007-01-01

Four 5-ac demonstration harvests were initiated in 1951 on the Bartlett Experimental Forest, New Hampshire: light selection, moderate selection, diameter limit, and liquidation. In 1952 and 1959, regeneration surveys were conducted that measured several different attributes of the seedlings and saplings in the cutover stands. In 2005, the stands were remeasured to...
How Are Investment Returns Affected By Competition Control and Southern Oak Seedling Survival?

Treesearch

Donald L. Grebner; Andrew W. Ezell; Deborah A. Gaddis; Steven H. Bullard

2004-01-01

Increasing numbers of landowners are establishing hardwood plantations to satisfy their management objectives. Despite a dearth of research on competition control and its effects on initial hardwood plantation survival and investment returns, this study examines alternative competition control regimes for southern oak establishment. The analysis includes estimates of...
EFFECTS OF CO2 AND O3 IN PONDEROSA PINE PLANT/LITTER/SOIL MESOCOSMS

EPA Science Inventory

Forested ecosysems are subjected to interacting conditions whose joint impacts may be quite different from those from single factors. To understand the impacts of CO2 and O3 on forest ecosystems, in April 1998, we initiated a four-year study of a Ponderosa pine seedling/soil/lit...
Some Growth Aspects of Seymeria cassioicies

Treesearch

Charles M. Stangle; Lytton J. Musselman

1981-01-01

The root parasite, Seymeria cassioides, will not initiate height growth without attachment to a host root when grown under normal fertility conditions, although the seedling may remain alive for 40 days or more without a host. During this time the roots elongate markedly. Fresh pine root segments do not influence the direction of root growth. Although S....
Genetic control of phyllotaxy phase shift in juvenile vines in a rootstock hybrid population

USDA-ARS?s Scientific Manuscript database

Grapevine seedlings initially display spiral phyllotaxy of true leaves, then undergo a shift to alternate phyllotaxy with the production of the first lateral meristems (typically tendrils). The node at which the shift from spiral to alternate phyllotaxy occurs varies from about the 4th to about the...
Control of Lophodermium needlecast disease in nurseries and Christmas tree plantations.

Treesearch

Thomas H. Nicholls; Darroll D. Skilling

1974-01-01

Recommendations are based upon studies initiated by the USDA Forest Service as a result of an outbreak of Lophodermium needlecast in several nurseries in the Lake States that spread to plantations throughout the United States due, in part, to shipment of diseased seedlings during the late 1960's and early 1970's.

Characteristics of gaps and natural regeneration in mature longleaf pine flatwoods ecosystems

Treesearch

Jennifer L. Gagnon; Eric J. Jokela; W.K. Moser; Dudley A. Huber

2004-01-01

Developing uneven-aged structure in mature stands of longleaf pine requires scientifically based silvicultural systems that are reliable, productive and sustainable. Understanding seedling responses to varying levels of site resource availability within forest gaps is essential for effectively converting even-aged stands to uneven-aged stands. A project was initiated...
Density and rectangularity of planting influence 20-year growth and development of red alder.

Treesearch

Dean S. DeBell; Constance A. Harrington

2002-01-01

Red alder (Alnus rubra Bong.) seedlings were planted in northwestern Oregon, U.S.A., at five initial spacings: 0.6 Ã 1.2 m, 1.2 Ã 1.2 m, 1.2 Ã 1.8 m, 1.8 Ã 1.8 m, and 2.5 Ã 2.5 m. Up to about age 10, tree and stand characteristics were correlated primarily with initial planting density in the expected manner; through age 20, however, tree growth...
Evaluations of plastic mesh tubes for protecting conifer seedling from pocket gophers in three western states

USGS Publications Warehouse

Engeman, Richard M.; Anthony, Richard M.; Barnes, Victor G.; Krupa, Heather W.; Evans, James

1999-01-01

The efficacy of plastic mesh tubes for protecting conifer seedlings from pocket gopher damage was evaluated on three national forest lands in three states. In each area, cohorts of 640 protected seedlings and 640 unprotected seedlings (3,840 total) were individually monitored for damage, survival, and growth twice each summer for 5 yr after planting. Substantial differences were found between protected and unprotected seedlings for time until occurrence of damage, survival time, proportion damaged and proportion surviving, as well as differences in growth. Over the three forest study sites, the proportion of unprotected seedlings damaged ranged from 60-89%, whereas the proportion of protected seedlings damaged after 5 yr ranged from 18-27%. The proportion of unprotected seedlings that died of gopher damage over 5 yr ranged from 46-64%, versus 1-19% for protected seedlings. Height growth was 25% greater for protected seedlings. Even when only undamaged seedlings were considered, protected seedlings exhibited superior height growth, possibly due to a more favorable microclimate provided by the tubes. These results were reflected in the higher and more uniform stocking rates for protected seedlings.
In vitro fertilisation in a small unit in the NHS

PubMed Central

Bromwich, Peter; Walker, Andrew; Kennedy, Stephen; Wiley, Mary; Little, David; Ross, Caroline; Sargent, Ian; Bellinger, Joan; O'Reilly, Helen; Lopez-Bernal, Andres; Brice, Amy L; Barlow, David

1988-01-01

In vitro fertilisation is one of the most effective new treatments for infertility, but financial restrictions have made it impossible for it to be widely carried out in the National Health Service. We report on the establishment of a small, largely self funded, unit that was set up with the help of the local health service management. All cycles are programmed so that most work is carried out during the working week; oocyte recoveries are performed as outpatient procedures without general anaesthesia and guided by ultrasound. Roughly a tenth of treatment cycles and roughly a fifth of embryo transfers resulted in a clinical pregnancy. PMID:3126964
Gel-coated tubes extend above-freezing storage of honey bee (Apis mellifera) semen to 439 days with production of fertilised offspring.

PubMed

Hopkins, Brandon K; Cobey, Susan W; Herr, Charles; Sheppard, Walter S

2017-09-01

Honey bees are an important agricultural species; however, relatively little work has been done to improve artificial reproductive technologies for this animal. The collection and distribution of germplasm for breeding and conservation is critical for improving managed honey bee populations and conserving threatened subspecies. The most efficient method of controlling breeding in honey bees is by artificial insemination. The collection of semen for insemination requires the use of antibiotics, which is especially critical if semen is to be stored for any length of time. The introduction of antibiotics is normally done through a balanced salt solution. In this study we compare, at two temperatures, the storage of undiluted semen in antibiotic-gel-coated capillary tubes with storage of semen diluted in a balanced salt solution containing antibiotics. Live-dead cell staining and artificial insemination of honey bee queens were performed at 45, 99 and 439 days after collection of the semen. In every case the antibiotic-gel-coated tube storage method at 14°C produced a higher percentage of fertilised offspring. This study demonstrates the longest period of time spermatozoa have been stored above freezing while maintaining fertilisation capacity.
Interaction between beet vinasse and iron fertilisers in the prevention of iron deficiency in lupins.

PubMed

de Santiago, Ana; Delgado, Antonio

2010-10-01

Recycling of organic byproducts for use as soil amendments or fertilisers may enhance the productivity of soils. The aim of this study was to investigate the potential of sugar beet vinasse to correct iron chlorosis in crops when applied in conjunction with Fe fertilisers such as vivianite and ferrous sulfate (FS). An experiment involving two factors (Fe source and dialysed sugar beet vinasse (DBV) rate) was performed using white lupin (Lupinus albus L.) and calcareous sand as growing medium. Although vivianite provided lower chlorophyll contents than Fe-chelate, dry matter production was not significantly different between the two Fe sources. Vivianite was more effective than FS in preventing iron chlorosis in white lupin, but not when DBV was applied. DBV significantly increased chlorophyll content in plants treated with FS after 3 weeks of growth. DBV increased the effect of FS in preventing iron deficiency chlorosis in white lupin. This was due, at least in part, to the inhibition of the precipitation of Fe oxides by organic compounds and to the increase in the content of Fe complexed by organic compounds in the growing medium, as revealed by sequential Fe fractionation. Copyright © 2010 Society of Chemical Industry.
Effect of open pulled straw (OPS) vitrification on the fertilisation rate and developmental competence of porcine oocytes.

PubMed

Varga, Erika; Gardón, J C; Papp, Agnes Bali

2006-03-01

Freezing technologies are very important to preserve gametes and embryos of animals with a good pedigree or those having high genetic value. The aim of this work was to compare immature and in vitro matured porcine oocytes regarding their morphology and ability to be fertilised after vitrification by the open pulled straw (OPS) method. In four experiments 830 oocytes were examined. To investigate the effect of cumulus cells on oocyte survival after OPS vitrification, both denuded and cumulus-enclosed oocytes were vitrified at the germinal vesicle (GV) stage, then after vitrification they were matured in vitro. Besides, in vitro matured oocytes surrounded with a cumulus and those without a cumulus were also vitrified. The survival of oocytes was evaluated by their morphology. After in vitro fertilisation the rates of oocytes penetrated by spermatozoa were compared. Our results suggest that the vitrification/warming procedure is the most effective in cumulus-enclosed oocytes (22.35 +/- 1.75%). There was no difference between the order of maturation and vitrification in cumulus-enclosed oocytes, which suggests the importance of cumulus cells in protecting the viability of oocytes during cryopreservation.
Rarity and persistence.

PubMed

Vermeij, Geerat J; Grosberg, Richard K

2018-01-01

Rarity is a population characteristic that is usually associated with a high risk of extinction. We argue here, however, that chronically rare species (those with low population densities over many generations across their entire ranges) may have individual-level traits that make populations more resistant to extinction. The major obstacle to persistence at low density is successful fertilisation (union between egg and sperm), and chronically rare species are more likely to survive when (1) fertilisation occurs inside or close to an adult, (2) mate choice involves long-distance signals, (3) adults or their surrogate gamete dispersers are highly mobile, or (4) the two sexes are combined in a single individual. In contrast, external fertilisation and wind- or water-driven passive dispersal of gametes, or sluggish or sedentary adult life habits in the absence of gamete vectors, appear to be incompatible with sustained rarity. We suggest that the documented increase in frequency of these traits among marine genera over geological time could explain observed secular decreases in rates of background extinction. Unanswered questions remain about how common chronic rarity actually is, which traits are consistently associated with chronic rarity, and how chronically rare species are distributed among taxa, and among the world's ecosystems and regions. © 2017 John Wiley & Sons Ltd/CNRS.
Considerations of viscosity in the preliminaries to mammalian fertilisation.

PubMed

Hunter, Ronald H F; Coy, P; Gadea, J; Rath, D

2011-03-01

Migration of spermatozoa in the female genital tract will be strongly influenced by the viscosity of the fluids encountered, yet little systematic analysis has been given to such a consideration. This essay reviews the series of milieux confronting a fertilising sperm during its progression to the oviduct ampulla. Two groups are discussed, first those in which ejaculation is into the vagina, second those in which semen enters the uterus during a protracted mating. Viscous glycoprotein secretions that accumulate in the oviduct isthmus of both groups before ovulation are highlighted, as is the environment generated in the ampulla by the post-ovulatory suspension of oocyte(s), cumulus cells and spermatozoa; follicular and peritoneal fluids may also be present. The viscosity of all female tract fluids responds to cyclical variations in temperature, and these exist within the oviduct near the time of ovulation. Gradations in viscosity influence the pattern and strength of sperm flagellar activity and the rate of forward movement. Measurements of sperm motility are currently made in a physiological medium of constant viscosity and temperature, thereby overlooking changes in the female genital tract. A more sophisticated approach might reveal an adequate fertilising potential in a proportion of putatively poor semen samples.
A Gift or a Waste? Quintavalle, Surplus Embryos and the Abortion Act 1967.

PubMed

Cherkassky, Lisa

2017-07-01

The destruction of an embryo must be justified in law. This is to prevent frivolous wastage and to show the respect afforded by the Warnock Report (1984). For example, embryonic destruction during pregnancy is underpinned by the Abortion Act 1967, and embryonic destruction during fertility treatment is regulated by the Human Fertilisation and Embryology Act 1990. However, following the appeal decision in R (Quintavalle) v Human Fertilisation and Embryology Authority (and Secretary of State for Health) [2005] 2 A.C. 561, embryos can now be created for a bone marrow tissue match to a sick sibling under the Human Fertility and Embryology Act 1990 according to the subjective desires of the mother. This opens the door to the first example of embryonic destruction on unique social-eugenic grounds with no clear lawful justification. It is argued that these embryos should be afforded a unique destruction provision under an amended version of section 1(1)(a) of the Abortion Act 1967 in light of their 'social-eugenic' nature. This would protect the Human Fertilisation and Embryology Authority from accusations of undercover eugenic practices and reinstate the respect shown towards embryos in law.
Coral Skeletons Provide Historical Evidence of Phosphorus Runoff on the Great Barrier Reef

PubMed Central

Mallela, Jennie; Lewis, Stephen E.; Croke, Barry

2013-01-01

Recently, the inshore reefs of the Great Barrier Reef have declined rapidly because of deteriorating water quality. Increased catchment runoff is one potential culprit. The impacts of land-use on coral growth and reef health however are largely circumstantial due to limited long-term data on water quality and reef health. Here we use a 60 year coral core record to show that phosphorus contained in the skeletons (P/Ca) of long-lived, near-shore Porites corals on the Great Barrier Reef correlates with annual records of fertiliser application and particulate phosphorus loads in the adjacent catchment. Skeletal P/Ca also correlates with Ba/Ca, a proxy for fluvial sediment loading, again linking near-shore phosphorus records with river runoff. Coral core records suggest that phosphorus levels increased 8 fold between 1949 and 2008 with the greatest levels coinciding with periods of high fertiliser-phosphorus use. Periods of high P/Ca correspond with intense agricultural activity and increased fertiliser application in the river catchment following agricultural expansion and replanting after cyclone damage. Our results demonstrate how coral P/Ca records can be used to assess terrestrial nutrient loading of vulnerable near-shore reefs. PMID:24086606
Simulation Modeling of Resilience Assessment in Indonesian Fertiliser Industry Supply Networks

NASA Astrophysics Data System (ADS)

Utami, I. D.; Holt, R. J.; McKay, A.

2018-01-01

Supply network resilience is a significant aspect in the performance of the Indonesian fertiliser industry. Decision makers use risk assessment and port management reports to evaluate the availability of infrastructure. An opportunity was identified to incorporate both types of data into an approach for the measurement of resilience. A framework, based on a synthesis of literature and interviews with industry practitioners, covering both social and technical factors is introduced. A simulation model was then built to allow managers to explore implications for resilience and predict levels of risk in different scenarios. Result of interview with respondens from Indonesian fertiliser industry indicated that the simulation model could be valuable in the assessment. This paper provides details of the simulation model for decision makers to explore levels of risk in supply networks. For practitioners, the model could be used by government to assess the current condition of supply networks in Indonesian industries. On the other hand, for academia, the approach provides a new application of agent-based models in research on supply network resilience and presents a real example of how agent-based modeling could be used as to support the assessment approach.
The effect of urea fertiliser formulations on gross nitrogen transformations in a permanent grassland soil.

NASA Astrophysics Data System (ADS)

Harty, Mary; Mueller, Christoph; Laughlin, Ronnie; Watson, Catherine; Richards, Karl; Lanigan, Gary; Forrestal, Patrick; McGeough, Karen

2015-04-01

Introduction By 2050, the current food production rate will need to increase by 70 % in order to meet the needs of the projected world population (FAO, 2014). Under the climate change response bill, Ireland has a target to reduce GHG emissions by 20% by 2020. Agriculture was responsible for almost one third of Ireland's overall Greenhouse Gas (GHG) emissions in 2012, with 39% of these emissions arising from chemical/organic fertilisers in the form of nitrous oxide (N2O). N2O losses represent environmental damage through ozone depletion and global warming as well as acidification, eutrophication, surface and groundwater contamination and it also represents financial loss to the farmer (Cameron 2013). The contradictory aims of increasing food production while reducing GHG emissions will require an adjustment to the current system of agricultural production. As part of a larger study evaluating the switching of nitrogen (N) fertiliser formulation to minimise N2O emissions, (from calcium ammonium nitrate (CAN) to urea based formulations), this experiment examined the effect of urea based fertiliser formulations on gross N transformations in a permanent pasture soil at Hillsborough, Co. Down, Northern Ireland. Study Design/Methodology A laboratory incubation study was undertaken, to examine the effect of urea in various combinations with two types of inhibitors on soil N dynamics and N2O and N2 emissions. The inhibitors examined were the urease inhibitor N-(butyl) thiophosphoric triamide (nBTPT) and the nitrification inhibitor dicyandiamide (DCD). The fertiliser products were labelled with 15N and the soil was incubated at 15 ° C at a water filled pore space of 65%. Soil mineral N (urea, NH4+, NO2- and NO3-) concentrations, gaseous losses (N2O and N2) and the 15N enrichments of NH4+, NO2-, NO3-, N2O and N2were analysed on 8 separate occasions over 25 days. An adapted numerical 15N tracing model (Müller et al., 2007) was used to quantify the effect of the inhibitors on soil gross N transformation rates and N2O and N2 emissions and the findings will be presented. Reference C. Müller, T. Rütting, J. Kattage, R.J. Laughlin & R.J. Stevens (2007). Estimation of parameters in complex 15N tracing by Monte Carlo sampling. Soil Biology and Biochemistry 39, 715-726.
Radiocaesium transfer from volcanic soils to Swiss chard, cabbage and sweet corn.

PubMed

Schuller, Paulina; Castillo, Alejandra; Voigt, Gabriele; Semioshkina, Natalia

2018-06-18

The root uptake of radiocaesium by different plant parts of Swiss chard (Beta vulgaris L. var. cicla), cabbage (Brassica oleracea L. var. capitata) and sweet corn (Zea mays L. var. saccharata) and the potential influence of K-fertilising on the transfer behaviour was studied in allophanic volcanic soils (umbric andosol and dystric fluvisol) in Chile under temperate climate and heavy rainfall conditions (∼2660 mm y -1 ) over several vegetation periods. The soils were spiked homogeneously to 0.20 m depth with 100 kBq 134 Cs m -2 and activity concentrations measured. The transfer factor (TF, on a dry mass basis) to Swiss chard had a clear exponential decrease within each crop year for both soil types, either K-fertilised or unfertilised. The highest values of the TFs to Swiss chard were at the beginning of the harvests, and the half-times of TF decrease ranged between 52 and 137 d for umbric andosol and between 40 and 164 d for dystric fluvisol. Over the five seasons there was no consistent ageing effect based on TF in either soil types for the three studied crops. The effect of 134 Cs foliar uptake by Swiss chard from resuspended soil was estimated to account for about 70% (external leaves) and 30% (internal leaves) increase in the TF for the K-unfertilised umbric andosol, and showed an ambiguous behaviour for the K-fertilised umbric andosol. Consequently foliar uptake does not explain the 370 and 500% increase of the TF to Swiss chard leaves determined during the third growing period in the umbric andosol without and with K-fertilisation, respectively. Therefore an uncertainty factor of 3-5 is recommended to be taken into account when using this parameter for dose calculations. The TF to Swiss chard was found to be higher than previously reported values. The TF to cabbage and sweet corn plant parts was found to be within the range of previously reported values. Normal K-fertilisation resulted in about 2.4-fold reduction in 134 Cs TF to Swiss chard, 2.3-fold to sweet corn and 3.0-fold to cabbage. Copyright © 2018 Elsevier Ltd. All rights reserved.
Woody plant establishment in grassed reclamation areas of the Athabasca oil sands

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fedkenheuer, A.W.

1980-12-01

The primary end land use for areas disturbed by the Syncrude Canada Ltd. oil sands surface mining venture is forest cover. Short term erosion control is of concern, however, and this results in the early establishment of a grass and legume cover. Problems have subsequently been encountered in attempts to establish woody plants in the grass and legume cover. Vegetation competition for soil moisture and nutrients and rodent damage to woody seedlings have been the major problem areas. A study was initiated in 1978 to evaluate methods of manipulating the grass and legume cover sufficiently to improve success rates inmore » establishing a variety of shrubs and trees. Five replicated treatments using the chemical herbicide glyphosate, soil scarification and fire alone plus soil scarification were established on an area seeded to grass and legumes in spring 1976. Woody plant survival and rodent damage, populations and distribution are being assessed annually in spring and fall. Rodent damage to woody seedlings was heavy in fall 1978 with 80 percent of the deciduous seedlings on non-scarified plots being damaged. In June 1979, 98 percent of the deciduous plants on the control and herbicide treatment areas were damaged. Damage to conifers was approximately 30 percent less during this time. Prescribed burning and mechanical scarification substantially reduced rodent damage. Seedling survival was variable with Amelanchier alnifolia, Pinus contorta and Populus tremuloides consistently exhibiting the highest survival rates.« less
Sediment burial stimulates the growth and propagule production of Spartina alterniflora Loisel.

NASA Astrophysics Data System (ADS)

Deng, Zifa; An, Shuqing; Zhao, Congjiao; Chen, Lin; Zhou, Changfang; Zhi, Yingbiao; Li, Hongli

2008-03-01

Spartina alterniflora Loisel., an extensively invasive species on the Chinese coast, is a focus of increasing management concern due to its high expansion rate in estuaries and tidal zone, and the significant damage it causes to native ecosystems. In order to understand the processes and mechanisms of invasion of S. alterniflora in China, the impact of three sediment types (sand, sand-loam mixture and loam) and five buried patterns (unburied, 50% burial of initial plant height, 75% burial of initial plant height, complete burial and repeated burial) on the growth of seedlings or ramets was investigated. Results showed that each of the three factors (sediment types, burial pattern and plant materials) and interactions between/among them, significantly affected height and clonal growth, and biomass accumulation and allocation. Plant height, total biomass and number of new vegetative propagules significantly increased with progressive burial treatments. However, the complete burial treatment resulted in the death of all plant materials, and the maximum values of three parameters were found in the 50% burial or repeated burial treatments. Plant responses were determined by the instantaneous thickness of sediment of each time burial rather than by the total quantity of repeated burial. The growth of S. alterniflora was not shown to be dependent on specific types of sediment in sedimentation environment. In contrast to the unburied control, the proportion of primary tillers produced directly from initial individuals and the ratio between the aboveground and belowground biomass were greater under burial treatments. Seedlings produced more new vegetative propagules than vegetative offspring in all experimental treatments, and the former were apt to produce ramets from rhizomes rather than primary tillers. It is concluded that under various sedimentation environments, the clonal spread efficiency of seedlings was higher than that of vegetative offspring, and there is a positive feedback relationship between sedimentation and the growth of S. alterniflora. Thus, moderate sedimentation may stimulate the invasion of exotic species, S. alterniflora in coastal China.
Hormone-Mediated Pattern Formation in Seedling of Plants: a Competitive Growth Dynamics Model

NASA Astrophysics Data System (ADS)

Kawaguchi, Satoshi; Mimura, Masayasu; Ohya, Tomoyuki; Oikawa, Noriko; Okabe, Hirotaka; Kai, Shoichi

2001-10-01

An ecologically relevant pattern formation process mediated by hormonal interactions among growing seedlings is modeled based on the experimental observations on the effects of indole acetic acid, which can act as an inhibitor and activator of root growth depending on its concentration. In the absence of any lateral root with constant hormone-sensitivity, the edge effect phenomenon is obtained depending on the secretion rate of hormone from the main root. Introduction of growth-stage-dependent hormone-sensitivity drastically amplifies the initial randomness, resulting in spatially irregular macroscopic patterns. When the lateral root growth is introduced, periodic patterns are obtained whose periodicity depends on the length of lateral roots. The growth-stage-dependent hormone-sensitivity and the lateral root growth are crucial for macroscopic periodic-pattern formation.
Study on tissue culture for Gelidium seedling

NASA Astrophysics Data System (ADS)

Pei, Lu-Qing; Luo, Qi-Jun; Fei, Zhi-Qing; Ma, Bin

1996-06-01

As seedling culture is a crucial factor for successful cultivation of Gelidium, the authors researched tissue culture technology for producing seedlings. The morphogeny and experimental ecology were observed and studied fully in 2 5 mm isolated tissue fragments. Regeneration, appearance of branching creepers and attaching structure and new erect seedlings production and development were studied. Fragments were sown on bamboo slice and vinylon rope. The seedlings were cultured 20 30 days indoor, then cultured in the sea, where the density of erect seedlings was 3 19 seedlings/cm2, growth rate was 3.84% day. The frond arising from seedlings directly was up to 10 cm per year. The ecological conditions for regenerated seedlings are similar to the natural ones. The regenerated seedlings are suitable for raft culture in various sea areas.
In planta transformation of pigeon pea: a method to overcome recalcitrancy of the crop to regeneration in vitro.

PubMed

Sankara Rao, K; Sreevathsa, Rohini; Sharma, Pinakee D; Keshamma, E; Udaya Kumar, M

2008-10-01

Development of transgenics in pigeon pea remains dogged by poor plant regeneration in vitro from transformed tissues and low frequency transformation protocols. This article presents a non-tissue culture-based method of generating transgenic pigeon pea (Cajanus cajan (L.) Millisp.) plants using Agrobacterium-Ti plasmid-mediated transformation system. The protocol involves raising of whole plant transformants (T0 plants) directly from Agrobacterium-infected young seedlings. The plumular and intercotyledonary meristems of the seedling axes are targeted for transformation. The transformation conditions optimized were, pricking of the apical and intercotyledonary region of the seedling axes of two-day old germinating seedlings with a sewing needle, infection with Agrobacterium (LBA4404/pKIWI105 carrying uid A and npt II genes) in Winans' AB medium that was added with wounded tobacco leaf extract, co-cultivation in the same medium for 1h and transfer of seedlings to soilrite for further growth and hardening and subsequent transfer of seedlings to soil in pots in the greenhouse. Out of the 22-25 primary transformants that survived infection-hardening treatments from each of the three experiments, 15 plants on the average established on the soil under greenhouse conditions, showed slow growth initially, nevertheless grew as normal plants, and flowered and set seed eventually. Of the several seeds harvested from all the T0 plants, six hundred were sown to obtain progeny (T1) plants and 350 of these were randomly analysed to determine their transgenic nature. PCR was performed for both gus (uid A) and npt II genes. Forty eight of the 350 T1 plants amplified both transgenes. Southern blot analysis substantiated the integration and transmission of these genes. The protocol ensured generation of pigeon pea transgenic plants with considerable ease in a short time and is applicable across different genotypes/cultivars of the crop and offers immense potential as a supplemental or an alternative protocol for generating transgenic plants of difficult-to-regenerate pigeon pea. Further, the protocol offers the option of doing away with a selection step in the procedure and so facilitates transformation, which is free of marker genes.
Ectomycorrhizal fungi reduce the light compensation point and promote carbon fixation of Pinus thunbergii seedlings to adapt to shade environments.

PubMed

Shi, Liang; Wang, Jie; Liu, Binhao; Nara, Kazuhide; Lian, Chunlan; Shen, Zhenguo; Xia, Yan; Chen, Yahua

2017-11-01

We examined the effects of three ectomycorrhizal (ECM) symbionts on the growth and photosynthesis capacity of Japanese black pine (Pinus thunbergii) seedlings and estimated physiological and photosynthetic parameters such as the light compensation point (LCP), biomass, and phosphorus (Pi) concentration of P. thunbergii seedlings. Through this investigation, we documented a new role of ectomycorrhizal (ECM) fungi: enhancement of the survival and competitiveness of P. thunbergii seedlings under low-light condition by reducing the LCP of seedlings. At a CO 2 concentration of 400 ppm, the LCP of seedlings with ECM inoculations was 40-70 μmol photons m -2 s -1 , significantly lower than that of non-mycorrhizal (NM) seedlings (200 μmol photons m -2 s -1 ). In addition, photosynthetic carbon fixation (Pn) increased with light intensity and CO 2 level, and the Pn of ECM seedlings was significantly higher than that of NM seedlings; Pisolithus sp. (Pt)- and Laccaria amethystea (La)-mycorrhizal seedlings had significantly lower Pn than Cenococcum geophilum (Cg)-mycorrhizal seedlings. However, La-mycorrhizal seedlings exhibited the highest fresh weight, relative water content (RWC), and the lowest LCP in the mycorrhizal group. Concomitantly, ECM seedlings showed significantly increased chlorophyll content of needles and higher Pi concentrations compared to NM seedlings. Overall, ECM symbionts promoted growth and photosynthesis while reducing the LCP of P. thunbergii seedlings. These findings indicate that ECM fungi can enhance the survival and competitiveness of host seedlings under low light.

Leafspot of Black Cherry (Pest Alert)

Treesearch

USDA Forest Service

1992-01-01

A leafspot caused by the fungus Blumeriella jaapii can damage black cherry seedlings in both forests and nurseries. The disease was formerly know as Coccomyces leafspot (from the genus of synonyms for the causal fungus). Affected leaves bear spots that initially are purple. In moist conditions, light-colored spore masses may ooze from fruiting bodies in these spots on...
Field performance of Nuttall Oak on former agricultural fields: Initial effects of nursery source and competition control

Treesearch

Emile S. Gardiner; K. Francis Salifu; Douglass F. Jacobs; George Hernandez; Ronald P. Overton

2007-01-01

Nuttall oak (Quercus nuttallii Palm.) seedlings raised at state nurseries in Mississippi, Louisiana, and Arkansas were morphologically different in height, root collar diameter, fresh mass, number of first-order lateral roots, root volume, and height-to-root collar diameter ratio. When outplanted on afforestation sites in the Lower Mississippi...
INTERACTIVE EFFECTS OF CO2 AND O3 ON A PONDEROSA PINE PLANT/LITTER/SOIL MESOCOSM

EPA Science Inventory

To study individual and combined impacts of two important atmospheric trace gases, CO2 and O3, on C and N cycling in forest ecosystems; a four-year experiment using a small-scale ponderosa pine (Pinus ponderosa Laws.) seedling/soil/litter system was initiated in April, 1998. Th...
Field performance of Nuttall oak on former agricultural fields: Initial effects of nursery source and competition control

Treesearch

Emile S. Gardiner; K. Francis Salifu; Douglass F. Jacobs; George Hernandez; Ronald P. Overton

2007-01-01

Nuttall oak (Quercus nuttallii Palm.) seedlings raised at state nurseries in Mississippi, Louisiana, and Arkansas were morphologically different in height, root collar diameter, fresh mass, number of first-order lateral roots, root volume, and height-to-root collar diameter ratio. When outplanted on afforestation sites in the Lower Mississippi...
Importance of Seedyear, Seedbed, and Overstory for Establishment of Natural Loblolly and Shortleaf Pine Regenerationin Southern Arkansas

Treesearch

Michael D. Cain

1991-01-01

First-year density and quadrat stocking of naturally established loblolly and shortleaf pine regeneration were monitored forfive consecutive seedyearson disturbed and undisturbed seedbeds. Compared to untreatedchecks,additional gainsin pine seedling density as a result of exposing mineral soil were not as great as initial gains achieved by control of overtopping...
Ensuring that forests are adapted to future climates

Treesearch

Brad St. Clair; Glenn Howe

2010-01-01

Successful reforestation requires that planted or naturally regenerated seedlings are well suited to a site. Genetic studies of forest trees provide ample evidence of large differences among seed sources in adaptive traits--traits such as the timing of growth initiation and cessation, cold and drought hardiness, and growth rates. Much of this variation is related to...
Overhead shading and growth of young longleaf pine

Treesearch

John C. Gilbert; John S. Kush; Ralph S. Meldahl; William D. Boyer; Dean H. Gjerstad

2014-01-01

A study to determine the effects of environmental conditions on the growth of longleaf pine (Pinus palustris Mill.) was initiated in 1969 on the Escambia Experimental Forest near Brewton, Alabama, USA. This study sample consisted of forty young naturally regenerated, even aged longleaf pine seedlings evenly divided between two soil types. At the beginning of the study...
Efficiency of seed production in southern pine seed orchards

Treesearch

David L. Bramlett

1977-01-01

Seed production in southern pine seed orchards can be evaluated by estimating the efficiency of four separate stages of cone, seed, and seedling development. Calculated values are: cone efficiency (CE), the ratio of mature cones to the initial flower crop; seed efficiency (SE), the ratio of filled seeds per cone to the seed potential; extraction efficiency (EE), the...
Big sagebrush (Artemisia tridentata) in a shifting climate context: Assessment of seedling responses to climate

Treesearch

Martha A. Brabec

2014-01-01

The loss of big sagebrush (Artemisia tridentata) throughout the Great Basin Desert has motivated efforts to restore it because of fire and other disturbance effects on sagebrush-dependent wildlife and ecosystem function. Initial establishment is the first challenge to restoration, and appropriateness of seeds, climate, and weather variability are factors that may...
Factors Limiting the Establishment of a Chaparral Oak, Quercus durata Jeps., in Grassland

Treesearch

Kimberlyn Williams; Stephen D. Davis; Barbara L. Gartner; Staffan Karlsson

1991-01-01

We studied factors that restrict colonization of grassland by Quercus durata Jeps., an oak commonly found in chaparral on serpentine soils. The study site contained a chaparral/ grassland border that had been stable for at least 50 years. Monitoring of acorns planted in the chaparral understory and grassland revealed that, although initial seedling...
FY18 SSC Agile-Seedling Fund Opportunities

NASA Technical Reports Server (NTRS)

Travis, Ramona

2017-01-01

The attached charts provide some background on an SSC (Stennis Space Center) initiative to support employees who may have ideas for technology development efforts but haven't been engaged in writing proposals to sources such as the Center Innovation Fund and other STMD (NASA Space Technology Mission Directorate) or HEOMD (NASA Human Exploration and Operations Mission Directorate) solicitation calls.
Quantitative trait loci associated with phenological development, low temperature tolerance, grain quality, and agronomic characters in wheat (Triticum aestivum L.)

USDA-ARS?s Scientific Manuscript database

Plants must respond to environmental cues and schedule their development in order to react to periods of abiotic stress and commit fully to growth and reproduction under favorable conditions. This study was initiated to identify SNP markers for characters expressed from the seedling stage to plant m...
Seedling growth and biomass allocation in relation to leaf habit and shade tolerance among 10 temperate tree species.

PubMed

Modrzyński, Jerzy; Chmura, Daniel J; Tjoelker, Mark G

2015-08-01

Initial growth of germinated seeds is an important life history stage, critical for establishment and succession in forests. Important questions remain regarding the differences among species in early growth potential arising from shade tolerance. In addition, the role of leaf habit in shaping relationships underlying shade tolerance-related differences in seedling growth remains unresolved. In this study we examined variation in morphological and physiological traits among seedlings of 10 forest tree species of the European temperate zone varying in shade tolerance and leaf habit (broadleaved winter-deciduous species vs needle-leaved conifers) during a 10-week period. Seeds were germinated and grown in a controlled environment simulating an intermediate forest understory light environment to resolve species differences in initial growth and biomass allocation. In the high-resource experimental conditions during the study, seedlings increased biomass allocation to roots at the cost of leaf biomass independent of shade tolerance and leaf habit. Strong correlations between relative growth rate (RGR), net assimilation rate (NAR), leaf area ratio (LAR), specific leaf area (SLA) and leaf mass fraction (LMF) indicate that physiology and biomass allocation were equally important determinants of RGR as plant structure and leaf morphology among these species. Our findings highlight the importance of seed mass- and seed size-related root morphology (specific root length-SRL) for shade tolerance during early ontogeny. Leaf and plant morphology (SLA, LAR) were more successful in explaining variation among species due to leaf habit than shade tolerance. In both broadleaves and conifers, shade-tolerant species had lower SRL and greater allocation of biomass to stems (stem mass fraction). Light-seeded shade-intolerant species with greater SRL had greater RGR in both leaf habit groups. However, the greatest plant mass was accumulated in the group of heavy-seeded shade-tolerant broadleaves. The results of our study suggest that the combinations of plant attributes enhancing growth under high light vary with shade tolerance, but differ between leaf habit groups. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
[Seedling index of Salvia miltiorrhiza and its simulation model].

PubMed

Huang, Shu-Hua; Xu, Fu-Li; Wang, Wei-Ling; Du, Jun-Bo; Ru, Mei; Wang, Jing; Cao, Xian-Yan

2012-10-01

Through the correlation analysis on the quantitative traits and their ratios of Salvia miltiorrhiza seedlings and seedling quality, a series of representative indices reflecting the seedling quality of the plant species were determined, and the seedling index suitable to the S. miltiorrhiza seedlings was ascertained by correlation degree analysis. Meanwhile, based on the relationships between the seedling index and the air temperature, solar radiation and air humidity, a simulation model for the seedling index of S. miltiorrhiza was established. The experimental data of different test plots and planting dates were used to validate the model. The results showed that the root diameter, stem diameter, crown dry mass, root dry mass, and plant dry mass had significant positive relationships with the other traits, and could be used as the indicators of the seedling's health. The seedling index of S. miltiorrhiza could be calculated by (stem diameter/root diameter + root dry mass/crown dry mass) x plant dry mass. The stem diameter, root dry mass, crown dry mass and plant dry mass had higher correlations with the seedling index, and thus, the seedling index determined by these indicators could better reflect the seedling's quality. The coefficient of determination (R2) between the predicted and measured values based on 1:1 line was 0.95, and the root mean squared error (RMSE) was 0.15, indicating that the model established in this study could precisely reflect the quantitative relationships between the seedling index of S. miltiorrhiza and the environmental factors.
Seedling mortality in Hawaiian rain forest: The role of small-scale physical disturbance

USGS Publications Warehouse

Drake, D.R.; Pratt, L.W.

2001-01-01

Most montane rain forests on the island of Hawaii consist of a closed canopy formed by Cibotium spp. tree ferns beneath an open canopy of emergent Metrosideros polymorpha trees. We used artificial seedlings to assess the extent to which physical disturbance caused by the senescing fronds of tree ferns and the activities of feral pigs might limit tree regeneration. Artificial seedlings were established terrestrially (N = 300) or epiphytically (N = 300) on tree fern stems. Half of the seedlings on each substrate were in an exclosure lacking feral pigs and half were in forest with pigs present. After one year, the percentage of seedlings damaged was significantly greater among terrestrial seedlings (25.7%) than epiphytic seedlings (11.3%). Significantly more terrestrial seedlings were damaged in the presence of pigs (31.3%) than in the absence of pigs (20.0%). Senescing fronds of tree ferns were responsible for 60.3 percent of the damaged seedlings. Physical disturbance is potentially a major cause of seedling mortality and may reduce the expected half-life of a seedling cohort to less than two years.
New Insights into How Increases in Fertility Improve the Growth of Rice at the Seedling Stage in Red Soil Regions of Subtropical China

PubMed Central

Li, Yilin; Shi, Weiming; Wang, Xingxiang

2014-01-01

The differences in rhizosphere nitrification activities between high- and low- fertility soils appear to be related to differences in dissolved oxygen concentrations in the soil, implying a relationship to differences in the radial oxygen loss (ROL) of rice roots in these soils. A miniaturised Clark-type oxygen microelectrode system was used to determine rice root ROL and the rhizosphere oxygen profile, and rhizosphere nitrification activity was studied using a short-term nitrification activity assay. Rice planting significantly altered the oxygen cycling in the water-soil system due to rice root ROL. Although the oxygen content in control high-fertility soil (without rice plants) was lower than that in control low-fertility soil, high rice root ROL significantly improved the rhizosphere oxygen concentration in the high-fertility soil. High soil fertility improved the rice root growth and root porosity as well as rice root ROL, resulting in enhanced rhizosphere nitrification. High fertility also increased the content of nitrification-induced nitrate in the rhizosphere, resulting in enhanced ammonium uptake and assimilation in the rice. Although high ammonium pools in the high-fertility soil increased rhizosphere nitrification, rice root ROL might also contribute to rhizosphere nitrification improvement. This study provides new insights into the reasons that an increase in soil fertility may enhance the growth of rice. Our results suggest that an amendment of the fertiliser used in nutrient- and nitrification-poor paddy soils in the red soil regions of China may significantly promote rice growth and rice N nutrition. PMID:25291182
Predicting the size and elevation of future mountain forests: Scaling macroclimate to microclimate

NASA Astrophysics Data System (ADS)

Cory, S. T.; Smith, W. K.

2017-12-01

Global climate change is predicted to alter continental scale macroclimate and regional mesoclimate. Yet, it is at the microclimate scale that organisms interact with their physiochemical environments. Thus, to predict future changes in the biota such as biodiversity and distribution patterns, a quantitative coupling between macro-, meso-, and microclimatic parameters must be developed. We are evaluating the impact of climate change on the size and elevational distribution of conifer mountain forests by determining the microclimate necessary for new seedling survival at the elevational boundaries of the forest. This initial life stage, only a few centimeters away from the soil surface, appears to be the bottleneck to treeline migration and the expansion or contraction of a conifer mountain forest. For example, survival at the alpine treeline is extremely rare and appears to be limited to facilitated microsites with low sky exposure. Yet, abundant mesoclimate data from standard weather stations have rarely been scaled to the microclimate level. Our research is focusing on an empirical downscaling approach linking microclimate measurements at favorable seedling microsites to the meso- and macro-climate levels. Specifically, mesoclimate values of air temperature, relative humidity, incident sunlight, and wind speed from NOAA NCEI weather stations can be extrapolated to the microsite level that is physiologically relevant for seedling survival. Data will be presented showing a strong correlation between incident sunlight measured at 2-m and seedling microclimate, despite large differences from seedling/microsite temperatures. Our downscaling approach will ultimately enable predictions of microclimate from the much more abundant mesoclimate data available from a variety of sources. Thus, scaling from macro- to meso- to microclimate will be possible, enabling predictions of climate change models to be translated to the microsite level. This linkage between measurement scales will enable a more precise prediction of the effects of climate change on the future extent and elevational distribution of our mountain forests and an accompanying array of critical ecosystem services.
Post-fire vegetation succession in Mediterranean gorse shrublands

NASA Astrophysics Data System (ADS)

De Luis, Martin; Raventós, José; González-Hidalgo, José Carlos

2006-07-01

In Western Mediterranean areas, forest fires are frequent in forests established on old croplands where post-fire regeneration is limited to obligate-seeder species. This has resulted in the spread of Mediterranean gorse ( Ulex parviflorus) increasing the risk and severity of fires. The aim of this paper is to test the autosuccessional hypothesis on a Mediterranean gorse shrubland dominated by seeders species. Particular objectives are: a) to analyze the effect of fire on seedling emergence, survival and growth on the main species involved on plant regeneration process. b) to identify changes in the relative abundance of species as consequence of fire by using a before-after experiment. Then, after experimental fires, seedling emergence, survival and growth rates were analyzed for the main species present in the vegetation regeneration process. Our results show that Mediterranean gorse communities are dominated by Fabaceae species (64% of individuals, mainly of Ulex parviflorus). However, our study demonstrates that vegetation regeneration after fire does not display an autosuccessional pattern and is produced a change on dominance from Fabaceae (mainly U. parviflorus) to Cistaceae (mainly C. albidus) species. Cistaceae seedlings (mainly Cistus albidus and Helianthemum marifolium) were the most abundant post-fire (63% of total germination) while species of Fabaceae (including U. parviflorus and Ononis fruticosa) represented 25%, and Lamiaceae (restricted to Rosmarinus officinalis) comprised only 3% of total emergences. Seedling survival did not differ significantly from one species to another (25-30% of initial individuals over 3 years) but seedling growth rates were also higher for Cistaceae than for Fabaceae individuals. Then, after fire, in terms of biomass, Fabaceae presence decreased from 78.7% to 13.1% while Cistaceae increase from 8% to 83.4%. Given that fire frequency, intensity or severity is partially controlled by the composition and structure of the plant community population changes in the main species, could affect the future fire regime and in turn, affect the hydrological, ecological and economic role of a large stretch of forest and woodland areas in western Mediterranean ecosystems.
Seedling Responses to Water Pulses in Shrubs with Contrasting Histories of Grassland Encroachment

PubMed Central

Woods, Steven R.; Archer, Steven R.; Schwinning, Susan

2014-01-01

Woody plant encroachment into grasslands has occurred worldwide, but it is unclear why some tree and shrub species have been markedly more successful than others. For example, Prosopis velutina has proliferated in many grasslands of the Sonoran Desert in North America over the past century, while other shrub species with similar growth form and life history, such as Acacia greggii, have not. We conducted a glasshouse experiment to assess whether differences in early seedling development could help explain why one species and not the other came to dominate many Sonoran Desert grasslands. We established eight watering treatments mimicking a range of natural precipitation patterns and harvested seedlings 16 or 17 days after germination. A. greggii had nearly 7 times more seed mass than P. velutina, but P. velutina emerged earlier (by 3.0±0.3 d) and grew faster (by 8.7±0.5 mg d−1). Shoot mass at harvest was higher in A. greggii (99±6 mg seedling−1) than in P. velutina (74±2 mg seedling−1), but there was no significant difference in root mass (54±3 and 49±2 mg seedling−1, respectively). Taproot elongation was differentially sensitive to water supply: under the highest initial watering pulse, taproots were 52±19 mm longer in P. velutina than in A. greggii. Enhanced taproot elongation under favorable rainfall conditions could give nascent P. velutina seedlings growth and survivorship advantages by helping reduce competition with grasses and maintain contact with soil water during drought. Conversely, A. greggii's greater investment in mass per seed appeared to provide little return in early seedling growth. We suggest that such differences in recruitment traits and their sensitivities to environmental conditions may help explain ecological differences between species that are highly similar as adults and help identify pivotal drivers of shrub encroachment into grasslands. PMID:24475263
Germination and initial growth of tree seedlings on deforested and natural forest soil at Dulhazara, Bangladesh.

PubMed

Hossain, M Mohitul

2012-12-01

The destruction of natural forest is increasing due to urbanization, industrialization, settlement and for the agricultural expansion over last few decades, and studies for their recovery need to be undertaken. With this aim, this comparative study was designed to see the effects of deforested soil on germination and growth performance of five different tree species. In the experiment, five species namely Gmelina arborea, Swietenia mahagoni, Dipterocarpus turbinatus, Acacia auriculiformis and Syzygium grande were germinated for six weeks on seedbeds and raised in pots (25cm diameter, 30cm height), that were filled with two soil and type of land use: deforested and adjacent natural forest of Dulhazara Safari Park. Growth performance of seedling was observed up to 15 months based on height, collar diameter and biomass production at the end. Our results showed that the germination rate was almost similar in both type of land uses. Height growth of D. turbinatus, G. arborea and S. mahagoni seedlings was almost similar and A. auriculi formis and S. grande lower in deforested soil compared to natural forest soil, while collar diameter ofA. auriculi formis, G. arborea, S. grande and S. mahagoni lower and D. turbinatus similar in deforested soil compared to natural forest soil. After uprooting at 19 months, S. mahagoni seedlings were showed significantly (p< or =0.05) higher oven dry biomass, D. turbinatus and A. auriculiformis higher, while G. arborea showed significantly (p< or =0.05) lower and S. grande almost similar oven dry biomass in deforested soil compared to natural forest soil. Oven dry biomass of D. turbinatus seedlings at 19 month age in deforested soil was 21.96g (n=5) and in natural forest soil 18.86g (n=5). However, differences in germination rate and growth performance for different tree species indicated that soil are not too much deteriorated through deforestation at Dulhazara and without any failure such deforested lands would be possible to bring under forest through plantation.

Cytoplasmic Calcium Increases in Response to Changes in the Gravity Vector in Hypocotyls and Petioles of Arabidopsis Seedlings1

PubMed Central

Toyota, Masatsugu; Furuichi, Takuya; Tatsumi, Hitoshi; Sokabe, Masahiro

2008-01-01

Plants respond to a large variety of environmental signals, including changes in the gravity vector (gravistimulation). In Arabidopsis (Arabidopsis thaliana) seedlings, gravistimulation is known to increase the cytoplasmic free calcium concentration ([Ca2+]c). However, organs responsible for the [Ca2+]c increase and the underlying cellular/molecular mechanisms remain to be solved. In this study, using Arabidopsis seedlings expressing apoaequorin, a Ca2+-sensitive luminescent protein in combination with an ultrasensitive photon counting camera, we clarified the organs where [Ca2+]c increases in response to gravistimulation and characterized the physiological and pharmacological properties of the [Ca2+]c increase. When the seedlings were gravistimulated by turning 180°, they showed a transient biphasic [Ca2+]c increase in their hypocotyls and petioles. The second peak of the [Ca2+]c increase depended on the angle but not the speed of rotation, whereas the initial peak showed diametrically opposite characters. This suggests that the second [Ca2+]c increase is specific for changes in the gravity vector. The potential mechanosensitive Ca2+-permeable channel (MSCC) inhibitors Gd3+ and La3+, the Ca2+ chelator 1,2-bis(2-aminophenoxy)ethane-N,N,N′,N′-tetraacetic acid (BAPTA), and the endomembrane Ca2+-permeable channel inhibitor ruthenium red suppressed the second [Ca2+]c increase, suggesting that it arises from Ca2+ influx via putative MSCCs in the plasma membrane and Ca2+ release from intracellular Ca2+ stores. Moreover, the second [Ca2+]c increase was attenuated by actin-disrupting drugs cytochalasin B and latrunculin B but not by microtubule-disrupting drugs oryzalin and nocodazole, implying that actin filaments are partially involved in the hypothetical activation of Ca2+-permeable channels. These results suggest that the second [Ca2+]c increase via MSCCs is a gravity response in the hypocotyl and petiole of Arabidopsis seedlings. PMID:18055589
[Physiological responses of mycorrhizal Pinus massoniana seedlings to drought stress and drought resistance evaluation].

PubMed

Wang, Yi; Ding, Gui-jie

2013-03-01

A greenhouse pot experiment was conducted to study the effects of inoculating Pisolithus tinctorius, Cenococcum geophilum, Cantharellus cibarius, and Suillus luteus on the physiological characteristics of Pinus massoniana seedlings under the conditions of drought stress and re-watering, with the drought resistance of the mycorrhizal seedlings evaluated. Under drought stress, the MDA content and membrane' s relative permeability of P. massoniana seedlings increased, but these two indices in the inoculated (mycorrhizal) seedlings were significantly lower than these in the un-inoculated (control) seedlings. After re-watering, the MDA content and membrane's relative permeability of mycorrhizal seedlings had a rapid decrease, as compared with the control. In the first 21 days of drought stress, the production rate of superoxide radical of the seedlings increased, and the SOD, POD and NR activities of mycorrhizal seedlings increased significantly. With the extending of drought stress, the seedlings after re-watering had different recovery ability. Under the re-watering after 14 days drought stress, the SOD, POD and NR activities recovered. The drought resistance of the mycorrhizal seedlings was in the order of Suillus luteus 1 > Suillus luteus 7 > Cantharellus cibarius > Cenococcum geophilum > Pisolithus tinctorius. The SOD and MDA activities had a greater correlation with the mycorrhizal seedlings drought resistance, being able to be used as the indicators to evaluate the drought resistance of mycorrhizal seedlings.
Bacillus amyloliquefaciens L-S60 Reforms the Rhizosphere Bacterial Community and Improves Growth Conditions in Cucumber Plug Seedling

PubMed Central

Qin, Yuxuan; Shang, Qingmao; Zhang, Ying; Li, Pinglan; Chai, Yunrong

2017-01-01

Vegetable plug seedling has become the most important way to produce vegetable seedlings in China. This seedling method can significantly improve the quality and yield of vegetables compared to conventional methods. In the process of plug seedling, chemical fertilizers or pesticides are often used to improve the yield of the seedlings albeit with increasing concerns. Meanwhile, little is known about the impact of beneficial bacteria on the rhizosphere microbiota and the growth conditions of vegetables during plug seedling. In this study, we applied a culture-independent next-generation sequencing-based approach and investigated the impact of a plant beneficial bacterium, Bacillus amyloliquefaciens L-S60, on the composition and dynamics of rhizosphere microbiota and the growth conditions of cucumbers during plug seedling. Our results showed that application of L-S60 significantly altered the structure of the bacterial community associated with the cucumber seedling; presence of beneficial rhizosphere species such as Bacillus, Rhodanobacter, Paenibacillus, Pseudomonas, Nonomuraea, and Agrobacterium was higher upon L-S60 treatment than in the control group. We also measured the impact of L-S60 application on the physiological properties of the cucumber seedlings as well as the availability of main mineral elements in the seedling at different time points during the plug seedling. Results from those measurements indicated that L-S60 application promoted growth conditions of cucumber seedlings and that more available mineral elements were detected in the cucumber seedlings from the L-S60 treated group than from the control group. The findings in this study provided evidence for the beneficial effects of plant growth-promoting rhizosphere bacteria on the bacterial community composition and growth conditions of the vegetables during plug seedling. PMID:29312278
Correlations between polyamine ratios and growth patterns in seedling roots

NASA Technical Reports Server (NTRS)

Shen, H. J.; Galston, A. W.

1985-01-01

The levels of putrescine, cadaverine, spermidine and spermine were determined in seedling roots of pea, tomato, millet and corn, as well as in corn coleoptiles and pea internodes. In all roots, putrescine content increased as elongation progressed, and the putrescine/spermine ratio closely paralleled the sigmoid growth curve up until the time of lateral root initiation. Spermidine and spermine were most abundant near the apices and declined progressively with increasing age of the cells. In the zone of differentiation of root hairs in pea roots, putrescine rose progressively with increasing age, while cadaverine declined. In both pea internodes and corn coleoptiles, the putrescine/spermidine ratio rises with increasing age and elongation. Thus, a block in the conversion of the diamine putrescine to the triamine spermidine may be an important step in the change from cell division to cell elongation.
High frequency early in vitro flowering of Dendrobium Madame Thong-In (Orchidaceae).

PubMed

Sim, Guek Eng; Loh, Chiang Shiong; Goh, Chong Jin

2007-04-01

We have successfully developed a method to induce early in vitro flowering of the self-pollinated seedlings of a tropical orchid hybrid, Dendrobium Madame Thong-In. Transition of vegetative shoot apical meristem to inflorescence meristem was observed when young protocorms were cultured in modified KC liquid medium. In contrast, protocorms cultured on Gelrite-solidified medium only produced axillary shoots and roots. CW was required to trigger the transitional shoot apical meristem and BA enhanced inflorescence stalk initiation and flower bud formation. However, normal flower development was deformed in liquid medium but developed fully upon transferring to two-layered (liquid over Gelrite-solidified) medium. Under optimal condition, in vitro flowering was observed about 5 months after seed sowing. Segregation of flower colours was observed in these seedlings and seedpods formed upon artificial pollination of the in vitro flowers.
Effect of pH and calcium on short-term NO3- fluxes in roots of barley seedlings

NASA Technical Reports Server (NTRS)

Aslam, M.; Travis, R. L.; Huffaker, R. C.

1995-01-01

The effect of pH and Ca2+ on net NO3- uptake, influx, and efflux by intact roots of barley (Hordeum vulgare L.) seedlings was studied. Seedlings were induced with NO3- or NO2-. Net NO3- uptake and efflux, respectively, were determined by following its depletion from, and accumulation in, the external solution. Since roots of both uninduced and NO2(-)-induced seedlings contain little internal NO3- initial net uptake rates are equivalent to influx (M. Aslam, R.L. Travis, R.C. Huffaker [1994] Plant Physiol 106: 1293-1301). NO3-, uptake (influx) by these roots was little affected at acidic pH. In contrast, in NO3(-)-induced roots, which accumulate NO3-, net uptake rates decreased in response to acidic pH. Under these conditions, NO3- efflux was stimulated and was a function of root NO3- concentration. Conversely, at basic pH, NO3- uptake by NO3- and NO2(-)-induced and uninduced roots decreased, apparently because of the inhibition of influx. Calcium had little effect on NO3- uptake (influx) by NO2(-)-induced roots at either pH 3 or 6. However, in NO3(-)-induced roots, lack of Ca2+ at pH 3 significantly decreased net NO3- uptake and stimulated efflux. The results indicate that at acidic pH the decrease in net NO3- uptake is due to the stimulation of efflux, whereas at basic pH, it is due to the inhibition of influx.
EMF radiations (1800 MHz)-inhibited early seedling growth of maize (Zea mays) involves alterations in starch and sucrose metabolism.

PubMed

Kumar, Arvind; Singh, Harminder Pal; Batish, Daizy R; Kaur, Shalinder; Kohli, Ravinder Kumar

2016-07-01

The present study investigated the impact of 1800-MHz electromagnetic field radiations (EMF-r), widely used in mobile communication, on the growth and activity of starch-, sucrose-, and phosphate-hydrolyzing enzymes in Zea mays seedlings. We exposed Z. mays to modulated continuous wave homogenous EMF-r at specific absorption rate (SAR) of 1.69±0.0 × 10(-1) W kg(-1) for ½, 1, 2, and 4 h. The analysis of seedlings after 7 days revealed that short-term exposure did not induce any significant change, while longer exposure of 4 h caused significant growth and biochemical alterations. There was a reduction in the root and coleoptile length with more pronounced effect on coleoptile growth (23 % reduction on 4-h exposure). The contents of photosynthetic pigments and total carbohydrates declined by 13 and 18 %, respectively, in 4-h exposure treatments compared to unexposed control. The activity of starch-hydrolyzing enzymes-α- and β-amylases-increased by ∼92 and 94 %, respectively, at an exposure duration of 4 h, over that in the control. In response to 4-h exposure treatment, the activity of sucrolytic enzymes-acid invertases and alkaline invertases-was increased by 88 and 266 %, whereas the specific activities of phosphohydrolytic enzymes (acid phosphatases and alkaline phosphatases) showed initial increase up to ≤2 h duration and then declined at >2 h exposure duration. The study concludes that EMF-r-inhibited seedling growth of Z. mays involves interference with starch and sucrose metabolism.
The severity of iron chlorosis in sensitive plants is related to soil phosphorus levels.

PubMed

Sánchez-Rodríguez, Antonio Rafael; del Campillo, María Carmen; Torrent, José

2014-10-01

Iron (Fe) deficiency chlorosis, a major nutritional problem in plants growing on calcareous soils, is related to the content and reactivity of soil iron oxides and carbonates. The effects of other soil components, however, need elucidation. In this paper we tested the hypothesis that application of high doses of phosphorus (P) to the soil can aggravate Fe chlorosis. Lupin and sorghum were grown on 24 calcareous soils. Leaf chlorophyll concentration (LCC) in lupin decreased with increasing available P/available Fe ratio in the native soil but LCC in sorghum was unaffected by that ratio. Application of P to the soil resulted in significant reduction of LCC and dry weight in lupin. In sorghum, LCC and dry weight were positively affected by P fertilisation for soils poor in available P whereas the opposite effect was generally observed for the P-rich soils. In another experiment where olive plants were pot-grown on two soils during the 2009–2011 period, P fertilisation affected LCC negatively only in 2009 and 2011 and in the soil that was poorer in iron oxides. Application of fertiliser P to Fe chlorosis-inducing soils is likely to aggravate this deficiency. However, this effect depends on the plant and the Fe and P statuses of the soil. © 2014 Society of Chemical Industry.
Agronomic properties of wastewater sludge biochar and bioavailability of metals in production of cherry tomato (Lycopersicon esculentum).

PubMed

Hossain, Mustafa K; Strezov, Vladimir; Chan, K Yin; Nelson, Peter F

2010-02-01

This work presents agronomic values of a biochar produced from wastewater sludge through pyrolysis at a temperature of 550 degrees C. In order to investigate and quantify effects of wastewater sludge biochar on soil quality, growth, yield and bioavailability of metals in cherry tomatoes, pot experiments were carried out in a temperature controlled environment and under four different treatments consisting of control soil, soil with biochar; soil with biochar and fertiliser, and soil with fertiliser only. The soil used was chromosol and the applied wastewater sludge biochar was 10tha(-1). The results showed that the application of biochar improves the production of cherry tomatoes by 64% above the control soil conditions. The ability of biochar to increase the yield was attributed to the combined effect of increased nutrient availability (P and N) and improved soil chemical conditions upon amendment. The yield of cherry tomato production was found to be at its maximum when biochar was applied in combination with the fertiliser. Application of biochar was also found to significantly increase the soil electrical conductivity as well as phosphorus and nitrogen contents. Bioavailability of metals present in the biochar was found to be below the Australian maximum permitted concentrations for food. Copyright (c) 2009 Elsevier Ltd. All rights reserved.
Radiation exposure related to the shipment of fertilisers to and from commercial ports: the case study of the seaport of Ravenna (Italy).

PubMed

Righi, Serena; Lucialli, Patrizia; Pollini, Elisa

2014-03-01

This paper presents the results of a study of radiological impacts related to the shipment of fertilisers to and from the commercial port of Ravenna (NE Italy). In particular, the effective doses to the port workers and members of the population surrounding the port area have been estimated. The study has included different types of measurement and assessment. First, the natural radioactivity of different fertilisers moving through the port has been determined: (40)K, (226)Ra, (210)Pb, (228)Ra and (228)Th concentrations have been analysed using γ-ray spectrometry, while (238)U and (232)Th concentrations have been determined by ICP-MS. At the same time, a dose rate meter and electret ion chambers were used to measure the external irradiation and the radon concentrations, respectively. Then, air pollutant dispersion models have been applied in order to assess particulate matter concentration in the port site and the surrounding residential areas, and consequently the inhalation doses. Finally, the annual effective doses to workers and local residents have been estimated. The effective doses to workers and the population have been estimated to be 0.9 mSv yr(-1) and 0.07 μSv yr(-1), respectively.
Desperately seeking donors: the 'saviour sibling' decision in Quintavalle v Human Fertilisation and Embryology Authority (UK).

PubMed

Hocking, Barbara Ann; Guy, Scott

2005-08-01

The recent House of Lords decision in Quintavalle v Human Fertilisation and Embryology Authority has raised difficult and complex issues regarding the extent to which embryo selection and reproductive technology can be used as a means of rectifying genetic disorders and treating critically ill children. This comment outlines the facts of Quintavalle and explores how the House of Lords approached the legal, ethical and policy issues that arose out of the Human Fertilisation and Embryology Authority's (UK) decision to allow reproductive and embryo technology to be used to produce a 'saviour sibling' whose tissue could be used to save the life of a critically ill child. Particular attention will be given to the implications of the decision in Quintavalle for Australian family and medical law and policy. As part of this focus, the comment explores the current Australian legislative and policy framework regarding the use of genetic and reproductive technology as a mechanism through which to assist critically ill siblings. It is argued that the present Australian framework would appear to impose significant limits on the medical uses of genetic technology and, in this context, would seem to reflect many of the principles that were articulated by the House of Lords in Quintavalle.
Optimised synthesis of ZnO-nano-fertiliser through green chemistry: boosted growth dynamics of economically important L. esculentum.

PubMed

Jabeen, Nyla; Maqbool, Qaisar; Bibi, Tahira; Nazar, Mudassar; Hussain, Syed Z; Hussain, Talib; Jan, Tariq; Ahmad, Ishaq; Maaza, Malik; Anwaar, Sadaf

2018-06-01

Mounting-up economic losses to annual crops yield due to micronutrient deficiency, fertiliser inefficiency and increasing microbial invasions (e.g. Xanthomonas cempestri attack on tomatoes) are needed to be solved via nano-biotechnology. So keeping this in view, the authors' current study presents the new horizon in the field of nano-fertiliser with highly nutritive and preservative effect of green fabricated zinc oxide-nanostructures (ZnO-NSs) during Lycopersicum esculentum (tomato) growth dynamics. ZnO-NS prepared via green chemistry possesses highly homogenous crystalline structures well-characterised through ultraviolet and visible spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction and scanning electron microscope. The ZnO-NS average size was found as small as 18 nm having a crystallite size of 5 nm. L. esculentum were grown in different concentrations of ZnO-NS to examine the different morphological parameters includes time of seed germination, germination percentage, the number of plant leaves, the height of the plant, average number of branches, days count for flowering and fruiting time period along with fruit quantity. Promising results clearly predict that bio-fabricated ZnO-NS at optimum concentration resulted as growth booster and dramatically triggered the plant yield.
Dicyandiamide and 3,4-dimethyl pyrazole phosphate decrease N2O emissions from grassland but dicyandiamide produces deleterious effects in clover.

PubMed

Macadam, Xana Melissa Belastegui; del Prado, Agustin; Merino, Pilar; Estavillo, José María; Pinto, Miriam; González-Murua, Carmen

2003-12-01

The application of nitrogen fertilisers leads to different ecological problems such as nitrate leaching and the release of nitrogenous gases. N2O is a gas involved in global warming, therefore, agricultural soils can be regarded as a source of global warming. Soil N2O production comes from both the nitrification and denitrification processes. From an ecological viewpoint, using nitrification inhibitors with ammonium based fertilisers may be a potential management strategy to lower the fluxes of N2O, thus decreasing its undesirable effect. In this study, the nitrification inhibitors (NIs) dicyandiamide (DCD) and 3,4-dimethyl pyrazole phosphate (DMPP) have been evaluated as management tools to mitigate N2O emissions from mineral fertilisation and slurry application in grassland systems (experiments 1 and 2), and to assess the phytotoxic effect of these inhibitors per se on clover (experiment 3). Both nitrification inhibitors acted in maintaining soil nitrogen (N) in ammonium form, decreasing cumulative N2O emissions. DCD, but not DMPP, produced phytotoxic effects and yield reduction in white clover. A nutrient imbalance, which led to a senescence process visually observed as chlorosis and necrosis at the border of the leaves, was noted.
Proteomic identification of OsCYP2, a rice cyclophilin that confers salt tolerance in rice (Oryza sativa L.) seedlings when overexpressed

PubMed Central

2011-01-01

Background High Salinity is a major environmental stress influencing growth and development of rice. Comparative proteomic analysis of hybrid rice shoot proteins from Shanyou 10 seedlings, a salt-tolerant hybrid variety, and Liangyoupeijiu seedlings, a salt-sensitive hybrid variety, was performed to identify new components involved in salt-stress signaling. Results Phenotypic analysis of one protein that was upregulated during salt-induced stress, cyclophilin 2 (OsCYP2), indicated that OsCYP2 transgenic rice seedlings had better tolerance to salt stress than did wild-type seedlings. Interestingly, wild-type seedlings exhibited a marked reduction in maximal photochemical efficiency under salt stress, whereas no such change was observed for OsCYP2-transgenic seedlings. OsCYP2-transgenic seedlings had lower levels of lipid peroxidation products and higher activities of antioxidant enzymes than wild-type seedlings. Spatiotemporal expression analysis of OsCYP2 showed that it could be induced by salt stress in both Shanyou 10 and Liangyoupeijiu seedlings, but Shanyou 10 seedlings showed higher OsCYP2 expression levels. Moreover, circadian rhythm expression of OsCYP2 in Shanyou 10 seedlings occurred earlier than in Liangyoupeijiu seedlings. Treatment with PEG, heat, or ABA induced OsCYP2 expression in Shanyou 10 seedlings but inhibited its expression in Liangyoupeijiu seedlings. Cold stress inhibited OsCYP2 expression in Shanyou 10 and Liangyoupeijiu seedlings. In addition, OsCYP2 was strongly expressed in shoots but rarely in roots in two rice hybrid varieties. Conclusions Together, these data suggest that OsCYP2 may act as a key regulator that controls ROS level by modulating activities of antioxidant enzymes at translation level. OsCYP2 expression is not only induced by salt stress, but also regulated by circadian rhythm. Moreover, OsCYP2 is also likely to act as a key component that is involved in signal pathways of other types of stresses-PEG, heat, cold, or ABA. PMID:21324151
The Impact of Using Alternative Forages on the Nutrient Value within Slurry and Its Implications for Forage Productivity in Agricultural Systems

PubMed Central

Crotty, Felicity V.; Fychan, Rhun; Theobald, Vince J.; Sanderson, Ruth; Chadwick, David R.; Marley, Christina L.

2014-01-01

Alternative forages can be used to provide valuable home-grown feed for ruminant livestock. Utilising these different forages could affect the manure value and the implications of incorporating these forages into farming systems, needs to be better understood. An experiment tested the hypothesis that applying slurries from ruminants, fed ensiled red clover (Trifolium pratense), lucerne (Medicago sativa) or kale (Brassica oleracea) would improve the yield of hybrid ryegrass (Lolium hybridicum), compared with applying slurries from ruminants fed ensiled hybrid ryegrass, or applying inorganic N alone. Slurries from sheep offered one of four silages were applied to ryegrass plots (at 35 t ha−1) with 100 kg N ha−1 inorganic fertiliser; dry matter (DM) yield was compared to plots only receiving ammonium nitrate at rates of 0, 100 and 250 kg N ha−1 year−1. The DM yield of plots treated with 250 kg N, lucerne or red clover slurry was significantly higher than other treatments (P<0.001). The estimated relative fertiliser N equivalence (FNE) (fertiliser-N needed to produce same yield as slurry N), was greatest for lucerne (114 kg) >red clover (81 kg) >kale (44 kg) >ryegrass (26 kg ha−1 yr−1). These FNE values represent relative efficiencies of 22% (ryegrass), 52% (kale), 47% (red clover) and 60% for lucerne slurry, with the ryegrass slurry efficiency being lowest (P = 0.005). Soil magnesium levels in plots treated with legume slurry were higher than other treatments (P<0.001). Overall, slurries from ruminants fed alternative ensiled forages increased soil nutrient status, forage productivity and better N efficiency than slurries from ruminants fed ryegrass silage. The efficiency of fertiliser use is one of the major factors influencing the sustainability of farming systems, these findings highlight the cascade in benefits from feeding ruminants alternative forages, and the need to ensure their value is effectively captured to reduce environmental risks. PMID:24830777
Mortality of nitrate fertiliser workers.

PubMed Central

Al-Dabbagh, S; Forman, D; Bryson, D; Stratton, I; Doll, R

1986-01-01

An epidemiological cohort study was conducted to investigate the mortality patterns among a group of workers engaged in the production of nitrate based fertilisers. This study was designed to test the hypothesis that individuals exposed to high concentrations of nitrates might be at increased risk of developing cancers, particularly gastric cancer. A total of 1327 male workers who had been employed in the production of fertilisers between 1946 and 1981 and who had been occupationally exposed to nitrates for at least one year were followed up until 1 March 1981. In total, 304 deaths were observed in this group and these were compared with expected numbers calculated from mortality rates in the northern region of England, where the factory was located. Analysis was also carried out separately for a subgroup of the cohort who had been heavily exposed to nitrates--that is, working in an environment likely to contain more than 10 mg nitrate/m3 for a year or longer. In neither the entire cohort nor the subgroup was any significant excess observed for all causes of mortality or for mortality from any of five broad categories of cause or from four specific types of cancer. A small excess of lung cancer was noted more than 20 years after first exposure in men heavily exposed for more than 10 years. That men were exposed to high concentrations of nitrate was confirmed by comparing concentrations of nitrates in the saliva of a sample of currently employed men with control men, employed at the same factory but not in fertiliser production. The men exposed to nitrate had substantially raised concentrations of nitrate in their saliva compared with both controls within the industry and with men in the general population and resident nearby. The results of this study therefore weight against the idea that exposure to nitrates in the environment leads to the formation in vivo of material amounts of carcinogens. PMID:3015194
Phosphorus and Defoliation Interact and Improve the Growth and Composition of the Plant Community and Soil Properties in an Alpine Pasture of Qinghai-Tibet Plateau.

PubMed

Qi, Juan; Nie, Zhongnan; Jiao, Ting; Zhang, Degang

2015-01-01

Pasture degradation caused by overgrazing and inappropriate fertiliser management is a major production and environmental threat in Qinghai-Tibet Plateau. Previous research has focused on the effects of mixed nitrogen (N) and phosphorus (P) fertiliser and reduced grazing pressure on the plant community of the grassland; however, the role of P and how it interacts with various defoliation (the process of the complete or partial removal of the above-ground parts of plants by grazing or cutting) intensities on the plant and soil of the grassland ecosystem have not been quantified. A field experiment was conducted to quantify how P application in combination of defoliation pressure could impact the dynamic change of the plant and soil in a native alpine grassland ecosystem of the Qinghai-Tibet Plateau, China, from May 2012 to September 2014. A split-plot design with 4 replicates and repeated measures was used to determine the growth and composition of plant community and soil physical and chemical properties under various levels of P fertiliser and defoliation intensity. The results showed that applying 20 kg P/ha increased the herbage yield of Melissitus ruthenica by 68% and total pasture yield by 25%. Close defoliation favoured the growth and plant frequency of the shorter species, whereas lax defoliation favoured that of the taller plant species. Medium P rate and cutting to 3 cm above ground gave an overall best outcome in pasture yield, quality and frequency and soil moisture and nutrient concentration. Application of P fertiliser with a moderate defoliation pressure to promote legume growth and N fixation has the potential to achieve multiple benefits in increasing pasture and livestock production and improving environmental sustainability in the alpine pasture of Qinghai-Tibet Plateau, a fragile and P-deficient ecosystem zone in China and its western neighbouring countries.
Iron budgets for three distinct biogeochemical sites around the Kerguelen archipelago (Southern Ocean) during the natural fertilisation experiment KEOPS-2

NASA Astrophysics Data System (ADS)

Bowie, A. R.; van der Merwe, P.; Quéroué, F.; Trull, T.; Fourquez, M.; Planchon, F.; Sarthou, G.; Chever, F.; Townsend, A. T.; Obernosterer, I.; Sallée, J.-B.; Blain, S.

2014-12-01

Iron availability in the Southern Ocean controls phytoplankton growth, community composition and the uptake of atmospheric CO2 by the biological pump. The KEOPS-2 experiment took place around the Kerguelen plateau in the Indian sector of the Southern Ocean, a region naturally fertilised with iron at the scale of hundreds to thousands of square kilometres, producing a mosaic of spring blooms which showed distinct biological and biogeochemical responses to fertilisation. This paper presents biogeochemical iron budgets (incorporating vertical and lateral supply, internal cycling, and sinks) for three contrasting sites: an upstream high-nutrient low-chlorophyll reference, over the plateau, and in the offshore plume east of Kerguelen Island. These budgets show that distinct regional environments driven by complex circulation and transport pathways are responsible for differences in the mode and strength of iron supply, with vertical supply dominant on the plateau and lateral supply dominant in the plume. Iron supply from "new" sources to surface waters of the plume was double that above the plateau and 20 times greater than at the reference site, whilst iron demand (measured by cellular uptake) in the plume was similar to the plateau but 40 times greater than the reference. "Recycled" iron supply by bacterial regeneration and zooplankton grazing was a relative minor component at all sites (<8% of "new" supply), in contrast to earlier findings from other biogeochemical iron budgets in the Southern Ocean. Over the plateau, a particulate iron dissolution term of 2.5% was invoked to balance the budget; this approximately doubled the standing stock of dissolved iron in the mixed layer. The exchange of iron between dissolved, biogenic and lithogenic particulate pools was highly dynamic in time and space, resulting in a decoupling of iron supply and carbon export and, importantly, controlling the efficiency of fertilisation.
Iron budgets for three distinct biogeochemical sites around the Kerguelen Archipelago (Southern Ocean) during the natural fertilisation study, KEOPS-2

NASA Astrophysics Data System (ADS)

Bowie, A. R.; van der Merwe, P.; Quéroué, F.; Trull, T.; Fourquez, M.; Planchon, F.; Sarthou, G.; Chever, F.; Townsend, A. T.; Obernosterer, I.; Sallée, J.-B.; Blain, S.

2015-07-01

Iron availability in the Southern Ocean controls phytoplankton growth, community composition and the uptake of atmospheric CO2 by the biological pump. The KEOPS-2 (KErguelen Ocean and Plateau compared Study 2) "process study", took place around the Kerguelen Plateau in the Indian sector of the Southern Ocean. This is a region naturally fertilised with iron on the scale of hundreds to thousands of square kilometres, producing a mosaic of spring blooms which show distinct biological and biogeochemical responses to fertilisation. This paper presents biogeochemical iron budgets (incorporating vertical and lateral supply, internal cycling, and sinks) for three contrasting sites: an upstream high-nutrient low-chlorophyll reference, over the plateau and in the offshore plume east of the Kerguelen Islands. These budgets show that distinct regional environments driven by complex circulation and transport pathways are responsible for differences in the mode and strength of iron supply, with vertical supply dominant on the plateau and lateral supply dominant in the plume. Iron supply from "new" sources (diffusion, upwelling, entrainment, lateral advection, atmospheric dust) to the surface waters of the plume was double that above the plateau and 20 times greater than at the reference site, whilst iron demand (measured by cellular uptake) in the plume was similar to that above the plateau but 40 times greater than at the reference site. "Recycled" iron supply by bacterial regeneration and zooplankton grazing was a relatively minor component at all sites (< 8 % of new supply), in contrast to earlier findings from other biogeochemical iron budgets in the Southern Ocean. Over the plateau, a particulate iron dissolution term of 2.5 % was invoked to balance the budget; this approximately doubled the standing stock of dissolved iron in the mixed layer. The exchange of iron between dissolved, biogenic particulate and lithogenic particulate pools was highly dynamic in time and space, resulting in a decoupling of the iron supply and carbon export and, importantly, controlling the efficiency of fertilisation.
Chemometric perspectives on plankton community responses to natural iron fertilisation over and downstream of the Kerguelen Plateau in the Southern Ocean

NASA Astrophysics Data System (ADS)

Trull, T. W.; Davies, D. M.; Dehairs, F.; Cavagna, A.-J.; Lasbleiz, M.; Laurenceau-Cornec, E. C.; d'Ovidio, F.; Planchon, F.; Leblanc, K.; Quéguiner, B.; Blain, S.

2015-02-01

We examined phytoplankton community responses to natural iron fertilisation at 32 sites over and downstream from the Kerguelen Plateau in the Southern Ocean during the austral spring bloom in October-November 2011. The community structure was estimated from chemical and isotopic measurements (particulate organic carbon - POC; 13C-POC; particulate nitrogen - PN; 15N-PN; and biogenic silica - BSi) on size-fractionated samples from surface waters (300, 210, 50, 20, 5, and 1 μm fractions). Higher values of 13C-POC (vs. co-located 13C values for dissolved inorganic carbon - DIC) were taken as indicative of faster growth rates and higher values of 15N-PN (vs. co-located 15N-NO3 source values) as indicative of greater nitrate use (rather than ammonium use, i.e. higher f ratios). Community responses varied in relation to both regional circulation and the advance of the bloom. Iron-fertilised waters over the plateau developed dominance by very large diatoms (50-210 μm) with high BSi / POC ratios, high growth rates, and significant ammonium recycling (lower f ratios) as biomass built up. In contrast, downstream polar frontal waters with a similar or higher iron supply were dominated by smaller diatoms (20-50 μm) and exhibited greater ammonium recycling. Stations in a deep-water bathymetrically trapped recirculation south of the polar front with lower iron levels showed the large-cell dominance observed on the plateau but much less biomass. Comparison of these communities to surface water nitrate (and silicate) depletions as a proxy for export shows that the low-biomass recirculation feature had exported similar amounts of nitrogen to the high-biomass blooms over the plateau and north of the polar front. This suggests that early spring trophodynamic and export responses differed between regions with persistent low levels vs. intermittent high levels of iron fertilisation.

Implementing the millennium development food security goals Challenges of the southern African context

NASA Astrophysics Data System (ADS)

Love, David; Twomlow, Steve; Mupangwa, Walter; van der Zaag, Pieter; Gumbo, Bekithemba

The Millennium Development Goals’ target to halve the proportion of people who suffer from hunger is extremely important in southern Africa, where food security has become increasingly problematic over the last 20 years. One “quick-win” proposal is replenishment of soil nutrients for smallholder farmers, through free or subsidised chemical fertilisers. Other proposals include appropriate irrigation technology, improved inputs and interventions targeted at women. Analysis of over 10 years of agro-hydrological and agro-economic studies from southern African show that a different approach is required to interventions proposed. There are sustainability problems with free chemical fertiliser due to transport costs and ancillary costs. Furthermore, recent studies in Zimbabwe and Mozambique show that significant increases in yield can only be obtained when soil fertility management is combined with good crop husbandry, e.g. timely planting and weeding. Ongoing replenishment of fertility would be dependent on a continued free or subsidised fertiliser supply, and transport system. Increasing access to irrigation will help, but is not the only solution and cannot reach even a majority of farmers. It has been determined that short dryspells are often the major cause of low yields in sub-Saharan Africa. Soil-water conservation approaches, e.g. winter weeding and conservation tillage, can reduce risk and increase yield. The following specific recommendations are made for urgent interventions to contribute sustainably to food security in southern Africa: (i) To increases access to fertiliser, consider development of strong input markets at end-user level. (ii) Intensification of technology transfer, focusing on capacity building for transfer of existing technologies and much closer collaboration between state and NGO sectors, agronomists and water engineers. (iii) Increasing the uptake of soil-water conservation methods, including conservation tillage and weeding, and supplementary irrigation to minimise adverse effects of dryspells, through investments in farmer training. (iv) Linking crop development strategies to livestock development practices and strategies. (v) Developing non-agro-based livelihood strategies in marginal lands.
Influence of a fertilizer solution on yield and quality of bread wheat in Guadalquivir Valley (Córdoba, Spain)

NASA Astrophysics Data System (ADS)

Concepción Benítez, M.; González, José Luis; Tejada, Manuel

2014-05-01

The use of by-products of food industries in agricultural practices has become a routine over the last few decades. The addition of beet vinasse, by-products of the two sep olive mill process and by-products of defatted sunflower flour, etc., to soils is a common agricultural practice, since sensible use has been reported to improve the physical, chemical and biological aspects of the soil and to increase harvest yield, and in many cases harvest quality Previous research carried out by the authors (Ordóñez et al., 2001) examined a process whereby a protein concentrate is obtained from defatted sunflower flour. In this process, floating liquid phosphorus, potassium contents and smaller amounts of humic substances and nitrogen are obtained. The potential application of this solution as a fertiliser has been evaluated on rye grass, confirming that its effects are comparable to those produced by a nutritional solution in terms of phosphorus and potassium foliar levels. The experiment was performed on soil classified as Typic Haploxererts located in the Middle Valley of the river Guadalquivir Cajeme wheat (Triticum aestivum var) variety was used at a dose of 180 kg seeds / ha. For both crop, four fertiliser treatments were applied in triplicate to randomly distributed 7 x 8 m plots. The greatest positive effect of applying the experimental phospho-potassic solution was found for the leaf levels of K, in maturity; this influence was most significant when the highest dosage of said solution. With reference to the levels of N, P and K in wheat grain, the levels of potassium were significantly different for all the fertilising treatments, and the plot fertilised with the highest dosage of the experimental phospho-potassic solution presented the highest values. As for the data obtained for harvest yield and quality, the addition of the experimental solution was observed to have a significantly positive influence (but only in the highest dosages) on the production levels.
Phosphorus and Defoliation Interact and Improve the Growth and Composition of the Plant Community and Soil Properties in an Alpine Pasture of Qinghai-Tibet Plateau

PubMed Central

Qi, Juan; Nie, Zhongnan; Jiao, Ting; Zhang, Degang

2015-01-01

Pasture degradation caused by overgrazing and inappropriate fertiliser management is a major production and environmental threat in Qinghai-Tibet Plateau. Previous research has focused on the effects of mixed nitrogen (N) and phosphorus (P) fertiliser and reduced grazing pressure on the plant community of the grassland; however, the role of P and how it interacts with various defoliation (the process of the complete or partial removal of the above-ground parts of plants by grazing or cutting) intensities on the plant and soil of the grassland ecosystem have not been quantified. A field experiment was conducted to quantify how P application in combination of defoliation pressure could impact the dynamic change of the plant and soil in a native alpine grassland ecosystem of the Qinghai-Tibet Plateau, China, from May 2012 to September 2014. A split-plot design with 4 replicates and repeated measures was used to determine the growth and composition of plant community and soil physical and chemical properties under various levels of P fertiliser and defoliation intensity. The results showed that applying 20 kg P/ha increased the herbage yield of Melissitus ruthenica by 68% and total pasture yield by 25%. Close defoliation favoured the growth and plant frequency of the shorter species, whereas lax defoliation favoured that of the taller plant species. Medium P rate and cutting to 3 cm above ground gave an overall best outcome in pasture yield, quality and frequency and soil moisture and nutrient concentration. Application of P fertiliser with a moderate defoliation pressure to promote legume growth and N fixation has the potential to achieve multiple benefits in increasing pasture and livestock production and improving environmental sustainability in the alpine pasture of Qinghai-Tibet Plateau, a fragile and P-deficient ecosystem zone in China and its western neighbouring countries. PMID:26513363
Health-promoting compounds of broccoli (Brassica oleracea L. var. italica) plants as affected by nitrogen fertilisation in projected future climatic change environments.

PubMed

Zaghdoud, Chokri; Carvajal, Micaela; Moreno, Diego A; Ferchichi, Ali; Del Carmen Martínez-Ballesta, María

2016-01-30

The complex interactions between CO2 increase and salinity were investigated in relation to decreased N supply, in order to determine the nutritional quality of broccoli (Brassica oleracea L. var. italica) plants under these conditions. Three different decreased N fertilisation regimes (NO3(-)/NH4(+) ratios of 100:0, 50:50 and 0:100 respectively) were combined with ambient (380 ppm) and elevated (800 ppm) [CO2 ] under non-saline (0 mmol L(-1) NaCl) and saline (80 mmol L(-1) NaCl) conditions. Nutrients (minerals, soluble protein and total amino acids) and natural antioxidants (glucosinolates, phenolic acids, flavonoids and vitamin C) were determined. In NH4(+) -fed broccoli plants, a marked growth reduction was shown and a redistribution of amino acids to cope with NH4(+) toxicity resulted in higher levels of indolic glucosinolate and total phenolic compounds. However, the positive effect of the higher [CO2] - ameliorating adverse effects of salinity--was only observed when N was supplied as NO3(-). Under reduced N fertilisation, the total glucosinolates were increased by a decreased NO3(-)/NH4 (+) ratio and elevated [CO2] but were unaffected by salinity. Under future climatic challenges, such as increased salinity and elevated [CO2], a clear genotypic dependence of S metabolism was observed in broccoli plants. In addition, an influence of the form in which N was supplied on plant nutritional quality was observed; a combined NO3(-)/NH4(+) (50:50) supply allowed broccoli plants not only to deal with NH4(+) toxicity but also to modify their glucosinolate content and profile. Thus, for different modes of N fertilisation, the interaction with climatic factors must be considered in the search for an optimal balance between yield and nutritional quality. © 2015 Society of Chemical Industry.
Marketing and Seedling Distribution of Longleaf Pine Seedlings

Treesearch

Mark J. Hainds

2002-01-01

The Longleaf Alliance, a partnership of people and organizations interested in longleaf pine, started tracking longleaf pine (Pinus palustris Mill.) seedling production in 1996. Total Longleaf seedling production has increased annually from 1996 to 2000. Bareroot seedling production decreased from 1996 to 1997, and decreased again from 1997 to 1998....
Synthesis of Pisolithus Ectomycorrhizae on Pecan Seedlings in Fumigated Soil

Treesearch

Donald H. Marx

1979-01-01

Curtis variety of pecan (Carya illinoensis) seedlings were grown for 8 months in fumigated soil infested at sowing with mycelial inoculum of Pisolithus tinctorius. Pisolithus ectomycorrhizae were formed on all inoculated seedlings and significantly improved their growth over control seedlings. Inoculated and control seedlings also formed ectomycorrhizae with naturally...
Survival and initial growth attributes of improved and unimproved cherrybark oak in South Arkansas

Treesearch

Joshua P. Adams; David Graves; Matthew H. Pelkki; Chris Stuhlinger; Jon Barry

2015-01-01

Thousands of acres are planted every year with genetically improved seedlings; but while pine continues to be extensively explored, the same is not true for hardwoods due to costs and rotation length. An improved cherrybark oak (Quercus pagodaRaf.) seed orchard exists in North Little Rock, AR, providing an opportunity to evaluate hardwood improvement. However, the cost...
Effects of understory prescribed burning on shortleaf pine (Pinus echinata Mill.)/mixed-hardwood forests

Treesearch

Katherine J. Elliott; James M. Vose

2005-01-01

We examined the effects of a single dormant season fire on overstory and understory species diversity and composition and tree seedling regeneration patterns the first and second years following a prescribed burn in the Conasauga River Watershed of southeastern Tennessee and northern Georgia. We asked: Can a single dormant season fire initiate a trajectory of overstory...
Wildfire rehabilitation success with and without chaining on the Henry Mountains, Utah

Treesearch

Cristina Juran; Bruce A. Roundy; James N. Davis

2008-01-01

We sampled unchained and chained areas in 2004 and 2005 on the Henry Mountains that had been aerially seeded after the Bulldog Fire of 2003. Establishment of seeded grasses was high on unchained and chained areas although chaining increased seeded grass establishment on some sites. Western yarrow established well on unchained areas. Initially, high seedling emergence...
Development of a mixed shrub–ponderosa pine community in a natural and treated condition

Treesearch

Philip M. McDonald; Gary O. Fiddler

1995-01-01

On a medium site in northern California, a mostly shrub community was treated by two manual release techniques and by two herbicides, to study its development in both a natural (control) and treated condition. Survival and growth of planted ponderosa pine seedlings were quantified for 8 to 11 years after initial treatment applications. Treatments included manual...
Seedfall, regeneration, and seedling development in group-selection openings

Treesearch

Philip M. McDonald; Celeste S. Abbott

1994-01-01

Forty-eight openings of 30, 60, and 90 feet in diameter were created in previously unmanaged mixed conifer-hardwood stands on a high-quality site in northern California in 1963. They were an attempt to convert an essentially even-aged forest to an uneven-aged arrangement and comprised the initial cut in the group-selection system. Five conifers and three hardwoods...
Role of fire in regeneration from seed: Chapter 14

USGS Publications Warehouse

Keeley, Jon E.; Fotheringham, C.J.; Fenner, M.

2000-01-01

The effects of fire on seed germination and plant regeneration are discussed. Among the topics considered are the triggering of opening of serotinous fruits or cones by fire, the breaking of dormancy in seeds in the soil seed bank, the effects of smoke on germination, and the role of fire in initiating seedling recruitment by opening gaps in closed vegetation.
Seedling response to initial oak woodland restoration treatments on the Ozark National Forest

Treesearch

Jamie L. Schuler; Don C. Bragg; Eric Heitzman; Jason Milks

2013-01-01

Over the last century, the range of oak woodland ecosystems has diminished as woodlands have become more closed-canopy forests. A century of fire suppression efforts has all but eliminated the frequent ground fires necessary to maintain the open canopy characteristics of oak woodland ecosystems. Restoration efforts are underway to return some of the closed-canopy...
Accelerated Growth and Initial Flowering of S2 Pinus Banksiana Selected for Precocious Flowering

Treesearch

Hyun Kang; Robert A. Cecich

1999-01-01

An accelerated growth protocol was applied in a greenhouse to hasten flowering in 13 S2 lines of jack pine (Pinus banksiana Lamb.) selected for precocious flowering. Seeds were sown on October 1. After the artificial "summer, fall, winter, and spring," seedlings were placed outdoors between June 20 and November 1. Ovulate strobili were...
Effects of prescribed burning on vegetation and fuel loading in three east Texas state parks

Treesearch

Sandra Rideout; Brian P. Oswald

2002-01-01

This study was conducted to evaluate the initial effectiveness of prescribed burning in the ecological restoration of forests within selected parks in east Texas. Twenty-four permanent plots were installed to monitor fuel loads, overstory, sapling, seedling, shrub and herbaceous layers within burn and control units of Mission Tejas, Tyler and Village Creek state parks...
The efficiency of introduced pisolithus tinctorius inoculum on backcrossed chestnut germination and survival

Treesearch

Jenise M. Bauman; Carolyn H. Keiffer; Shiv Hiremath

2012-01-01

American chestnut was eliminated as a canopy tree from the Appalachian region of North America with the introduction of chestnut blight in the early 1900s. Breeding programs initiated in the 1980s have produced seedling lines that display the pure American morphology with potential resistance to chestnut blight. More work is required to assess their field performance...
Survival and First-Year Growth of Hardwoods Planted in Saturated Soils

Treesearch

F. T. Bonner

1966-01-01

Up to 16 weeks of soil saturation from the time of planting did not significantly affect survival, date of bud-break, or initiation of height growth of sycamore, sweetgum, and Nuttall oak seedlings. But when soil temperatures were rapidly increasing in mid-April, saturation for more than 10 to 12 weeks did severely reduce height, root, and stem-diameter growth....
Transient heat stress compromises the resistance of wheat (Poales: Poaceae) seedlings to Hessian fly (Diptera: Cecidomyiidae) infestation.

PubMed

Currie, Yaleaka; Moch, John; Underwood, Joshua; Kharabsheh, Hamzah; Quesenberry, Amy; Miyagi, Risa; Thomas, Carolyn; Boney, Melanie; Woods, Samantha; Chen, Ming-Shun; Zhu, Lieceng

2014-02-01

Heat stress exerts a profound impact on the resistance of plants to parasites. In this research, we investigated the impact of an acute transient heat stress on the resistance of the wheat line 'Molly,' which contains the R gene H13, to an avirulent Hessian fly (Mayetiola destructor (Say)) population. We found that a significant portion of Molly seedlings stressed at 40 degrees C for 6 h during or after the initial Hessian fly larval attack became susceptible to otherwise avirulent insects, whereas unstressed control plants remained 100% resistant. Specifically, 77.8, 73.3, 83.3, and 46.7% of plants heat stressed at 0, 6,12, and 24 h, respectively, after the initial larval attack became susceptible. Biochemical analysis revealed that heat stress caused a transient decrease in 12-oxo-phytodienoic acid, but an increase in salicylic acid accumulation in Molly plants. The change in phytohormones after heat stress and Hessian fly infestation was not observed in 'Newton,' a near-isogenic but Hessian fly susceptible wheat line. Instead, heat stress caused a relatively prolonged reduction in palmitoleic acid. The role of phytohormones in heat-induced loss of wheat resistance was discussed.
Utilisation of young and old soil carbon sources by microbial groups differ during the growing season and between experimental treatments in a long-term field experiment

NASA Astrophysics Data System (ADS)

Börjesson, Gunnar; Menichetti, Lorenzo; Thornton, Barry; Campbell, Colin; Kätterer, Thomas

2014-05-01

Soil organic matter (SOM)is the largest active carbon pool in the terrestrial environment. SOM is a key factor for soil fertility, but is also important for the sequestration of atmospheric CO2. In agricultural soils, management of plant residues and the use of organic fertilisers play important roles for maintaining SOM. Switching from C3 plants to C4 plants such as maize, enables a natural labelling in situ; when coupled with compound specific 13C isotope analysis of phospholipid fatty acids (PLFAs) it allows the proportion of new C (fixed after the switch added to soil from above- and belowground litter and root exudates) and the proportion of old C (fixed prior to the switch derived from turnover of organic matter) utilised by the soil microbial community to be determined. (new paragraph) A field experiment in Sweden, amended with different mineral and organic fertilisers since 1956, was grown with C3 plants, mainly cereals until 1999. From the year 2000 silage maize was grown every year. In 2012, soil from four replicate plots of five experimental treatments, N fertilised, N fertilised amended with straw and sewage sludge, and two controls (bare fallow and cropped unfertilised) were sampled three times, at the start, middle and end of the growing season. Phospholipid fatty acids (PLFAs) were extracted from all soil samples and analysed for concentrations and 13C content. (new paragraph) Total PLFA concentrations and also the PLFA/SOM ratios increased with SOM in the different treatments. Seasonal variation in total PLFA was small except for the most SOM-rich treatment (sewage sludge) where concentrations significantly decreased during the growing season indicating the depletion of a labile SOM pool. Weighted mean values of δ13C in PLFAs show that the plots fertilised with only calcium nitrate had the highest δ13C-values in PLFAs before (-20.24 o) and after the vegetation period (-20.37 o), due to a large input of 13C-enriched plant material. However, during the vegetation period the values were much lower (-21.85 o). This coincided with a strong increase of the PLFA 18:2 (from 0.99 up to 2.37 nmol g dry wt soil-1), indicating utilisation of old organic matter by fungi, while mono-unsaturated PLFAs, indicating Gram-negative bacteria, were more frequent before and after the growing season. Microbial dynamics in the unfertilised control followed the same seasonal pattern but PLFAs were less enriched in 13C due to lower yields compared with the N-fertilised treatment. The addition of organic amendments (straw or sewage sludge) lowered δ13C-values in PLFAs below values of the control due to input of labile material with C3-origin. PLFAs in the bare fallow treatment, that had not received plant carbon inputs during twelve years, were most 13C depleted among the treatments but still enriched by about 2o compared with SOM, indicating a degree of microbial fractionation.
[Effect of ectomycorrhizae on the growth of Picea koraiensis seedlings].

PubMed

Song, Rui-Qing; Wu, Ke

2005-12-01

Basidioscarps of Agaricales in different Picea koraiensis forest plantations were collected during August-October, 2000. 36 isolaters of species of Agaricales were obtained by isolating and culturing to the basidioscarps. Through indoor inoculation test on seedlings of Picea koraiensis, 6 ectomycorrhizae fungi cultures were obtained from 36 isolaters. The inoculation results show that the period for ectomycorrhizae inoculation to 1-year seedlings of Picea koraiensis should be about 30 days after seedlings emerging, the suitable temperature for ectomycorrhizae forming is about 20 degrees C. 6 ectomycorrhizae strains all have growth-promoting effect to the seedlings of Picea koraiensis. The contents of chlorophyll a of the seedlings inoculated strains of Agaricus silvaticus, 031 and L15 were significantly higher than other strains and control. The contents of chlorophyll b in the seedlings inoculated strains 009, 004, Agaricus silvaticus and L15 were significantly higher than other strains and control. The weights of seedlings which inoculated strains 009, 025, 031, Agaricus silvaticus and L15 were significantly different to control, the weight of seedlings inoculated strains of Agaricus silvaticus and L15 are 19.23% and 23.08% more than control; The heights of the seedlings inoculated 6 strains all have significant difference to control, the weight of seedlings inoculated strains of Agaricus silvaticus and L15 are 17.83% and 16.37% more than control. The results of outdoor inoculation show that the seedlings inoculated Agaricus silvaticus grow best on height, 9.25% more than control after inoculated 70 days; the seedlings inoculated strain L15 grow best on collar diameter, 9.92% more than control after inoculated 70 days; the lateral root numbers of seedlings inoculated strain 009 is largest, 51.91% more than control after inoculated 70 days; the main roots of seedlings inoculated strain 009 are longest, 3.36% more than control after inoculated 70 days; the ectomycorrhizae fungi infestation percentage of seedlings inoculated strain 031 is highest, 13.90% more than control after inoculated 70 days; the photosynthesis of seedlings inoculated strain 031 is more powerful, 20.02% more than control after inoculated 70 days. To sum up, strain 009, strain 031 and strain L15 should be fine strains to seedlings of Picea koraiensis.

Combined effects of cotyledon excision and nursery fertilization on root growth, nutrient status and outplanting performance of Quercus variabilis container seedlings

PubMed Central

Shi, Wenhui; Bloomberg, Mark; Li, Guolei; Su, Shuchai; Jia, Liming

2017-01-01

Artificial excision of the distal part of acorns in order to promote germination is well researched in oak seedling cultivation studies. However, studies of combined effects of cotyledon excision and nursery fertilization on container seedlings are lacking, especially for seedling root growth and outplanting performance. This study aimed to explore the main effects of cotyledon excision on Quercus variabilis seedling emergence characteristics and demonstrated the combined effects of cotyledon excision and nursery fertilization on seedling quality to improve Quercus variabilis seedling outplanting performance. Four cotyledon excision treatments and two classes of nursery fertilization were implemented. Seedling emergence was noted every week after sowing. Seedling dry mass, morphology, and nutrient status were assessed at the end of the nursery season. After the first outplanting season, the aforementioned measurements along with seedling survival were determined once again. The results showed that cotyledon excision generally induced greater and more rapid seedling emergence, but did not affect shoot emergence synchronicity. The highest total emergence and emergence rate occurred with Intermediate excision (1/2 of the distal end of acorn was excised). Effects of nutrient loss due to cotyledon excision on seedling quality and outplanting performance were somewhat compensated by nursery fertilization. Nursery fertilization promoted dry mass increment (the net increment from T0 to T2 for dry mass) for excised seedlings after outplanting, resulting in better performance for Slight (1/3 of the distal end of acorn was excised) and Intermediate excision treatments in the field. Thus we conclude Intermediate excision combined with reasonable nursery fertilization can be recommended for production of nursery grown seedlings for afforestation. PMID:28545103
Combined effects of cotyledon excision and nursery fertilization on root growth, nutrient status and outplanting performance of Quercus variabilis container seedlings.

PubMed

Shi, Wenhui; Bloomberg, Mark; Li, Guolei; Su, Shuchai; Jia, Liming

2017-01-01

Artificial excision of the distal part of acorns in order to promote germination is well researched in oak seedling cultivation studies. However, studies of combined effects of cotyledon excision and nursery fertilization on container seedlings are lacking, especially for seedling root growth and outplanting performance. This study aimed to explore the main effects of cotyledon excision on Quercus variabilis seedling emergence characteristics and demonstrated the combined effects of cotyledon excision and nursery fertilization on seedling quality to improve Quercus variabilis seedling outplanting performance. Four cotyledon excision treatments and two classes of nursery fertilization were implemented. Seedling emergence was noted every week after sowing. Seedling dry mass, morphology, and nutrient status were assessed at the end of the nursery season. After the first outplanting season, the aforementioned measurements along with seedling survival were determined once again. The results showed that cotyledon excision generally induced greater and more rapid seedling emergence, but did not affect shoot emergence synchronicity. The highest total emergence and emergence rate occurred with Intermediate excision (1/2 of the distal end of acorn was excised). Effects of nutrient loss due to cotyledon excision on seedling quality and outplanting performance were somewhat compensated by nursery fertilization. Nursery fertilization promoted dry mass increment (the net increment from T0 to T2 for dry mass) for excised seedlings after outplanting, resulting in better performance for Slight (1/3 of the distal end of acorn was excised) and Intermediate excision treatments in the field. Thus we conclude Intermediate excision combined with reasonable nursery fertilization can be recommended for production of nursery grown seedlings for afforestation.
Review and analysis of global agricultural N₂O emissions relevant to the UK.

PubMed

Buckingham, S; Anthony, S; Bellamy, P H; Cardenas, L M; Higgins, S; McGeough, K; Topp, C F E

2014-07-15

As part of a UK government funded research project to update the UK N2O inventory methodology, a systematic review of published nitrous oxide (N2O) emission factors was carried out of non-UK research, for future comparison and synthesis with the UK measurement based evidence base. The aim of the study is to assess how the UK IPCC default emission factor for N2O emissions derived from synthetic or organic fertiliser inputs (EF1) compares to international values reported in published literature. The availability of data for comparing and/or refining the UK IPCC default value and the possibility of analysing sufficient auxiliary data to propose a Tier 2 EF1 reporting strategy is evaluated. The review demonstrated a lack of consistency in reporting error bounds for fertiliser-derived EFs and N2O flux data with 8% and 44% of publications reporting EF and N2O flux error bounds respectively. There was also poor description of environmental (climate and soil) and experimental design auxiliary data. This is likely to be due to differences in study objectives, however potential improvements to soil parameter reporting are proposed. The review demonstrates that emission factors for agricultural-derived N2O emissions ranged -0.34% to 37% showing high variation compared to the UK Tier 1 IPCC EF1 default values of 1.25% (IPCC 1996) and 1% (IPPC 2006). However, the majority (83%) of EFs reported for UK-relevant soils fell within the UK IPCC EF1 uncertainty range of 0.03% to 3%. Residual maximum likelihood (REML) analysis of the data collated in the review showed that the type and rate of fertiliser N applied and soil type were significant factors influencing EFs reported. Country of emission, the length of the measurement period, the number of splits, the crop type, pH and SOC did not have a significant impact on N2O emissions. A subset of publications where sufficient data was reported for meta-analysis to be conducted was identified. Meta-analysis of effect sizes of 41 treatments demonstrated that the application of fertiliser has a significant effect on N2O emissions in comparison to control plots and that emission factors were significantly different to zero. However no significant relationships between the quantity of fertiliser applied and the effect size of the amount of N2O emitted from fertilised plots compared to control plots were found. Annual addition of fertiliser of 35 to 557 kg N/ha gave a mean increase in emissions of 2.02 ± 0.28 g N2O/ha/day compared to control treatments (p<0.01). Emission factors were significantly different from zero, with a mean emission factor estimated directly from the meta analysis of 0.17 ± 0.02%. This is lower than the IPCC 2006 Tier 1 EF1 value of 1% but falling within the uncertainty bound for the IPCC 2006 Tier 1 EF1 (0.03% to 3%). As only a small number of papers were viable for meta analysis to be conducted due to lack of reporting of the key controlling factors, the estimates of EF in this paper cannot include the true variability under conditions similar to the UK. Review-derived EFs of 0.34% to 37% and mean EF from meta-analysis of 0.17 ± 0.02% highlight variability in reporting EFs depending on the method applied and sample size. A protocol of systematic reporting of N2O emissions and key auxiliary parameters in publications across disciplines is proposed. If adopted this would strengthen the community to inform IPCC Tier 2 reporting development and reduce the uncertainty surrounding reported UK N2O emissions. Copyright © 2014 Elsevier B.V. All rights reserved.
Morphological and physiological evaluations of seedling quality

Treesearch

Diane L. Haase

2007-01-01

Seedling quality and subsequent field performance can be influenced by various stress factors. Measuring seedling quality can help to identify possible crop problems in order to make informed decisions for culturing, lifting, storing, and planting. In addition, seedling quality data can help seedling growers and users to better understand annual patterns among species...
Effects of vesicular-arbuscular mycorrhizal (VAM) fungi on the seedling growth of three Pistacia species.

PubMed

Caglar, S; Akgun, A

2006-07-01

The experiment was undertaken to test the efficiency of inoculation of vesicular-arbuscular mycorrhizal (VAM) fungi on the seedling growth of three Pistacia species used as rootstocks. The stratified Pistacia seeds were inoculated with VAM fungi. The highest rate of inoculated roots was 96.7% in P. khinjuck seedlings with G. clarum and G. etunicatum, 83.3% in P. vera seedlings with G. caledonium and 73.3% in P. terebinthus seedlings with G. caledonium. Mycorrhizal inoculations improved seedling height only in P. terebinthus. Certain mycorrhizal inoculations increased the leaf N, but not P and K contents. Seedlings inoculated with G. caledonium had higher reducing sugar contents. It was concluded that pre-inoculated Pistacia seedlings could have a better growth in the harsh field conditions.
The potential for mycobiont sharing between shrubs and seedlings to facilitate tree establishment after wildfire at Alaska arctic treeline.

PubMed

Hewitt, Rebecca E; Chapin, F Stuart; Hollingsworth, Teresa N; Taylor, D Lee

2017-07-01

Root-associated fungi, particularly ectomycorrhizal fungi (EMF), are critical symbionts of all boreal tree species. Although climatically driven increases in wildfire frequency and extent have been hypothesized to increase vegetation transitions from tundra to boreal forest, fire reduces mycorrhizal inoculum. Therefore, changes in mycobiont inoculum may potentially limit tree-seedling establishment beyond current treeline. We investigated whether ectomycorrhizal shrubs that resprout after fire support similar fungal taxa to those that associate with tree seedlings that establish naturally after fire. We then assessed whether mycobiont identity correlates with the biomass or nutrient status of these tree seedlings. The majority of fungal taxa observed on shrub and seedling root systems were EMF, with some dark septate endophytes and ericoid mycorrhizal taxa. Seedlings and adjacent shrubs associated with similar arrays of fungal taxa, and there were strong correlations between the structure of seedling and shrub fungal communities. These results show that resprouting postfire shrubs support fungal taxa compatible with tree seedlings that establish after wildfire. Shrub taxon, distance to the nearest shrub and fire severity influenced the similarity between seedling and shrub fungal communities. Fungal composition was correlated with both foliar C:N ratio and seedling biomass and was one of the strongest explanatory variables predicting seedling biomass. While correlative, these results suggest that mycobionts are important to nutrient acquisition and biomass accrual of naturally establishing tree seedlings at treeline and that mycobiont taxa shared by resprouting postfire vegetation may be a significant source of inoculum for tree-seedling establishment beyond current treeline. © 2017 John Wiley & Sons Ltd.
Improvement in the yield and quality of kalmegh (Andrographis paniculata Nees) under the sustainable production system.

PubMed

Verma, Rajesh Kumar; Verma, Sanjeet K; Pankaj, Umesh; Gupta, Anand K; Khan, Khushboo; Shankar, Karuna

2015-02-01

Andrographis paniculata Nees is an annual erect herb with wide medicinal and pharmacological applications due to the presence of andrographolide and other active chemical constituents. The large-scale cultivation of the kalmegh is not in practice. The aim of this study was to establish sustainable production systems of A. paniculata cv CIM-Megha with the application of different bioinoculants and chemical fertilisers. A. paniculata herb and andrographolide yield in the dried leaves was found to be highest (218% and 61.3%, respectively) in treatment T3 (NPK+Bacillus sp.) compared with T1 (control). The soil organic carbon, soil microbial respiration, soil enzymes activity and available nutrients improved significantly with combined application of bioinoculants and chemical fertilisers.
Epiphytic lichen community dynamics in deciduous forests around a phosphorus fertiliser factory in Central Lithuania.

PubMed

Motiejūnaite, Jurga

2007-03-01

The detailed dynamics of epiphytic lichen communities were observed while studying permanent quadrats in the zone of influence of a phosphorus fertiliser factory in central Lithuania. The most significant changes were induced by several factors: changes in macroenvironment (increase of illumination), bark scaling, succession processes, individual growth characteristics of the community members, and influence of fungal infection and invertebrate grazing. None of these changes could be directly linked with air pollution. These observations have shown that in conditions of more or less stable pollution, epiphytic community dynamics should be evaluated with care, the best indicators of the characteristics of the communities being species richness and presence/absence and abundance of indicator (nitrophilous or acidophilous) species.
Controlled release fertilizer improves quality of container longleaf pine seedlings

Treesearch

R. Kasten Dumroese; Jeff Parkhurst; James P. Barnett

2005-01-01

In an operational trial, increasing the amount of nitrogen (N) applied to container longleaf pine seedlings by incorporating controlled release fertilizer (CRF) into the media improved seedling growth and quality. Compared with control seedlings that received 40 mg N, seedlings receiving 66 mg N through CRF supplemented with liquid fertilizer had needles that were 4 in...
Winter injury among white fir seedlings...unusual pattern in seed source study

Treesearch

M. Thompson Conkle; W. J. Libby; J. L. Hamrick

1967-01-01

White fir seeds collected from 43 sources were sown at the Institute of Forest Genetics, Placerville, Calif. in 1963. Observations made 3 years later showed that seedlings from northern sources sustained more winter injury than did southern origin seedlings. Seedlings from low elevations were less severely damaged than seedlings from higher elevations in the same...
Interaction of Soil Moisture and Seedling Shelters on Water Relations of Baldcypress Seedlings

Treesearch

Ty Swirin; Hans Williams; Bob Keeland

1999-01-01

Stomata1 conductance, transpiration, and leaf water potential were measured during the 1996 growing season on baldcypress (Taxodium disfichum (L.) Rich.) seedlings. Seedlings were hand-planted from 1-O bareroot stock in mesic and permanently Rooded soil conditions. One-half of all seedlings were fitted with 122-cm tall polyethylene tree...
Spring Burn Aids Longleaf Pine Seedling Height Growth

Treesearch

William R. Maple

1977-01-01

Prescribed burning in midspring may stimulate height growth of longleaf pine seedlings. Seedlings were planted on sandy and clayey sites that were prescribed burned 2 years later. Treatments were cool, moderate, and hot burns and an unburned control. The hot, May burn significantly increased height growth of seedlings on the sandy site. The number of seedlings with 50...
Protecting red oak seedlings with tree shelters in northwestern Pennsylvania

Treesearch

Russell S. Walters; Russell S. Walters

1993-01-01

Examines the growth and survival of planted and natural red oak seedlings and seedlings from planted acorns within translucent tan tree shelters, fences, and unprotected controls under a shelterwood seed-cut stand. Seedlings planted within tree shelters and fences were inside tree shelters. Natural seedlings grew very little and their height inside and outside of tree...
Early field performance of Acacia koa seedlings grown under subirrigation and overhead irrigation

Treesearch

Anthony S. Davis; Jeremiah R. Pinto; Douglass F. Jacobs

2011-01-01

Koa (Acacia koa A. Gray [Fabaceae]) seedlings were grown with subirrigation and overhead irrigation systems in an effort to characterize post-nursery field performance. One year following outplanting, we found no differences in seedling height or survival, but root-collar diameter was significantly larger for subirrigated seedlings. This indicates that koa seedlings,...
A comparison of tree shelters installed on green ash and cherrybark oak seedlings in Arkansas

Treesearch

H. Christoph Stuhlinger

2013-01-01

Tree shelters can aid hardwood seedling establishment by improving early seedling survival and growth. This study was established in Arkansas to compare three types of tree shelters installed on green ash (Fraxinus pennsylvanica Marsh.) and cherrybark oak (Quercus pagoda Raf.) seedlings. Seedlings planted in 4 feet tall Blue-XÂ®,...
Ethylene-Inhibited Jasmonic Acid Biosynthesis Promotes Mesocotyl/Coleoptile Elongation of Etiolated Rice Seedlings[OPEN

PubMed Central

Xiong, Qing; Ma, Biao; Lu, Xiang; Huang, Yi-Hua; He, Si-Jie; Yang, Chao; Yin, Cui-Cui; Zhou, Yang; Wang, Wen-Sheng; Li, Zhi-Kang; Chen, Shou-Yi

2017-01-01

Elongation of the mesocotyl and coleoptile facilitates the emergence of rice (Oryza sativa) seedlings from soil and is affected by various genetic and environment factors. The regulatory mechanism underlying this process remains largely unclear. Here, we examined the regulation of mesocotyl and coleoptile growth by characterizing a gaoyao1 (gy1) mutant that exhibits a longer mesocotyl and longer coleoptile than its original variety of rice. GY1 was identified through map-based cloning and encodes a PLA1-type phospholipase that localizes in chloroplasts. GY1 functions at the initial step of jasmonic acid (JA) biosynthesis to repress mesocotyl and coleoptile elongation in etiolated rice seedlings. Ethylene inhibits the expression of GY1 and other genes in the JA biosynthesis pathway to reduce JA levels and enhance mesocotyl and coleoptile growth by promoting cell elongation. Genetically, GY1 acts downstream of the OsEIN2-mediated ethylene signaling pathway to regulate mesocotyl/coleoptile growth. Through analysis of the resequencing data from 3000 rice accessions, we identified a single natural variation of the GY1 gene, GY1376T, which contributes to mesocotyl elongation in rice varieties. Our study reveals novel insights into the regulatory mechanism of mesocotyl/coleoptile elongation and should have practical applications in rice breeding programs. PMID:28465411
Vine maple (Acer circinatum) clone growth and reproduction in managed and unmanaged coastal Oregon douglas-fir forests

USGS Publications Warehouse

O'Dea, Mary E.; Zasada, John C.; Tappeiner, John C.

1995-01-01

Vine maple (Acer circinatum Pursh.) clone development, expansion, and regeneration by seedling establishment were studied in 5-240 yr old managed and unmanaged Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) stands in coastal Oregon. Stem length, number of stems, and crown area were all significantly (P @10 m long and basal sprouts 1-2 m long; some stems had been pinned to the forest floor by fallen trees or branches and had layered. In stands >120 yr in age, clones were often quite complex, composed of several decumbent stems each of which connected the ramets of 1-10 new aerial stems. Vine maple clone expansion occurs by the layering of long aerial stems. Over 95% of the layered stems we observed had been pinned to the forest floor by fallen debris. Unsevered stems that we artificially pinned to the forest floor initiated roots within 1 yr. Thinning may favor clonal expansion because fallen slash from thinning often causes entire clones to layer, not just individual stems. Clonal vine maple seed production and seedling establishment occurred in all stages of stand development except dense, young stands following crown closure. There were more seedlings in thinned stands than in unthinned stands and in unburned clearcuts than in burned clearcuts.
Trichoderma harzianum containing 1-aminocyclopropane-1-carboxylate deaminase and chitinase improved growth and diminished adverse effect caused by Fusarium oxysporum in soybean.

PubMed

Zhang, Fuli; Chen, Can; Zhang, Fan; Gao, Lidong; Liu, Jidong; Chen, Long; Fan, Xiaoning; Liu, Chang; Zhang, Ke; He, Yuting; Chen, Chen; Ji, Xiue

2017-03-01

An isolate, named Trichoderma harzianum T-soybean, showed growth-promoting for soybean seedlings and induced resistance to Fusarium oxysporum under greenhouse. Compared to control soybean seedlings, fresh weight, dry weight, lateral root number, chlorophyll content, root activity and soluble protein of plants pretreated with T-soybean increased, but initial pod height reduced. Furthermore, we found that T-soybean inhibited the growth of F. oxysporum by parasitic function. In addition, plate test results showed that culture filtrates of T-soybean also inhibited significantly F. oxysporum growth. Meanwhile, T-soybean treatment obviously reduced disease severity and induced quickly the H 2 O 2 and O 2 - burst as well as pathogenesis related protein gene (PR3) expression after F. oxysporum inoculation, and subsequently diminished the cell damage in soybean caused by the pathogen challenge. Reactive oxygen species (ROS) scavenging enzymes activity analysis showed that the activities of peroxidase (POD), polyphenol oxidase (PPO) and superoxide dismutase (SOD) increased significantly in T-soybean pretreated plants. These results suggested that T-soybean treatment induced resistance in soybean seedlings to F. oxysporum by companying the production of ROS and the increasing of ROS scavenging enzymes activity as well as PR3 expression. Copyright © 2016 Elsevier GmbH. All rights reserved.
Socio-demographic and clinical characteristics of clients seeking assisted conception at Lagos State University Teaching Hospital, Ikeja, Nigeria.

PubMed

Adewunmi, Adeniyi A; Ottun, Tawakwalit A; Abiara, Tayo; Chukwuma, Jane-Frances; Okorie, Lauretta

2017-10-01

The socio-demographic and clinical characteristics of 246 consecutive couples seeking assisted conception in a university teaching hospital in Nigeria from inception in 2011 till 2014 were reviewed restrospectively. Eighty-five (34.5%) were in the 35-40 years age group. The body mass index of the women showed that 111 (45.1%) were overweight. One hundred and ninety five (88%) were referred on account of secondary infertility. The mean duration of infertility was 9.6 ± 4.8 years. Major factors identified were male factor 128 (52%), ovarian/age-related decline in fertility 107 (43.5%), tubal 83 (33.7%) and combined male/female factor 71 (28.9%). One hundred and ninety (77.2%) clients seeking assisted conception were Christians at advanced age (greater than 35 years) with a longstanding duration of infertility of more than 10 years. Government, private and religious organisations need to raise public awareness about the availability of in-vitro fertilisation services as well as encourage early resort to assisted reproductive technologies. Impact statement What we already know: Secondary infertility due mainly to tubal factor is reported to be the commonest cause of infertility in developing countries like Nigeria and clients affected seek assisted reproductive techniques late. What the results of this study add: Male factor infertility is more common amongst infertile couples seeking in vitro fertilisation in LASUTH. The implications of the findings for practice and/or further research: A thorough examination of the male partner followed by investigation is vital at the initial visit so that they can be referred early for assisted conception.
Iron-mediated changes in phytoplankton photosynthetic competence during SOIREE

NASA Astrophysics Data System (ADS)

Boyd, P. W.; Abraham, E. R.

Active fluorescence (fast repetition rate fluorometry, FRRF) was used to follow the photosynthetic response of the phytoplankton community during the 13-day Southern Ocean Iron RElease Experiment (SOIREE). This in situ iron enrichment was conducted in the polar waters of the Australasian-Pacific sector of the Southern Ocean in February 1999. Iron fertilisation of these high nitrate low chlorophyll (HNLC) waters resulted in an increase in the photosynthetic competence ( Fv/ Fm) of the resident cells from around 0.20 to greater than 0.60 (i.e. close to the theoretical maximum) by 10/11 days after the first enrichment. Although a significant iron-mediated response in Fv/ Fm was detected as early as 24 h after the initial fertilisation, the increase in Fv/ Fm to double ambient levels took 6 days. This response was five-fold slower than observed in iron enrichments (in situ and in vitro) in the HNLC waters of the subarctic and equatorial Pacific. Although little is known about the relationship between water temperature and Fv/ Fm, it is likely that low water temperatures — and possibly the deep mixed layer — were responsible for this slow response time. During SOIREE, the photosynthetic competence of the resident phytoplankton in iron-enriched waters increased at dissolved iron levels above 0.2 nM, suggesting that iron limitation was alleviated at this concentration. Increases in Fv/ Fm of cells within four algal size classes suggested that all taxa displayed a photosynthetic response to iron enrichment. Other physiological proxies of algal iron stress (such as flavodoxin levels in diatoms) exhibited different temporal trends to iron-enrichment than Fv/ Fm during the time-course of SOIREE. The relationship between Fv/ Fm, algal growth rate and such proxies in Southern Ocean waters is discussed.

Establishing northern red oak on a degraded upland site in northeastern Pennsylvania: Influence of seedling pedigree and quality

Treesearch

Cornelia C. Pinchot; Thomas J. Hall; Scott E. Schlarbaum; Arnold M. Saxton; James Bailey

2017-01-01

Enrichment plantings using large oak seedlings of regional sources may promote superior survival and growth compared to direct seeding or standard nursery seedling material. This study evaluated the survival and growth of planted 1-0 northern red oak (Quercus rubra L.) seedlings among 11 families and 3 seedling size classes (small, average, and...
Combined effects of pre-hardening and fall fertilization on nitrogen translocation and storage in Quercus variabilis seedlings

Treesearch

Guolei Li; Yan Zhu; Yong Liu; Jiaxi Wang; Jiajia Liu; R. Kasten Dumroese

2014-01-01

Maintaining proper seedling nitrogen status is important for outplanting success. Fall fertilization of evergreen conifer seedlings is a well-known technique for averting nitrogen (N) dilution caused by continued seedling growth during hardening. For deciduous seedlings, this technique is much less understood, and regardless of foliage type, the interaction of N status...
Arbuscular Mycorrhizal Symbiosis Modulates Antioxidant Response and Ion Distribution in Salt-Stressed Elaeagnus angustifolia Seedlings.

PubMed

Chang, Wei; Sui, Xin; Fan, Xiao-Xu; Jia, Ting-Ting; Song, Fu-Qiang

2018-01-01

Elaeagnus angustifolia L. is a drought-resistant species. Arbuscular mycorrhizal symbiosis is considered to be a bio-ameliorator of saline soils that can improve salinity tolerance in plants. The present study investigated the effects of inoculation with the arbuscular mycorrhizal fungus Rhizophagus irregularis on the biomass, antioxidant enzyme activities, and root, stem, and leaf ion accumulation of E. angustifolia seedlings grown during salt stress conditions. Salt-stressed mycorrhizal seedlings produced greater root, stem, and leaf biomass than the uninoculated stressed seedlings. In addition, the seedlings colonized by R. irregularis showed notably higher activities of superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX) in the leaves of the mycorrhizal seedlings in response to salinity compared to those of the non-mycorrhizal seedlings. Mycorrhizal seedlings not only significantly increased their ability to acquire K + , Ca 2+ , and Mg 2+ , but also maintained higher K + :Na + ratios in the leaves and lower Ca 2+ :Mg 2+ ratios than non-mycorrhizal seedlings during salt stress. These results suggest that the salt tolerance of E. angustifolia seedlings could be enhanced by R. irregularis. The arbuscular mycorrhizal symbiosis could be a promising method to restore and utilize salt-alkaline land in northern China.
Arbuscular Mycorrhizal Symbiosis Modulates Antioxidant Response and Ion Distribution in Salt-Stressed Elaeagnus angustifolia Seedlings

PubMed Central

Chang, Wei; Sui, Xin; Fan, Xiao-Xu; Jia, Ting-Ting; Song, Fu-Qiang

2018-01-01

Elaeagnus angustifolia L. is a drought-resistant species. Arbuscular mycorrhizal symbiosis is considered to be a bio-ameliorator of saline soils that can improve salinity tolerance in plants. The present study investigated the effects of inoculation with the arbuscular mycorrhizal fungus Rhizophagus irregularis on the biomass, antioxidant enzyme activities, and root, stem, and leaf ion accumulation of E. angustifolia seedlings grown during salt stress conditions. Salt-stressed mycorrhizal seedlings produced greater root, stem, and leaf biomass than the uninoculated stressed seedlings. In addition, the seedlings colonized by R. irregularis showed notably higher activities of superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX) in the leaves of the mycorrhizal seedlings in response to salinity compared to those of the non-mycorrhizal seedlings. Mycorrhizal seedlings not only significantly increased their ability to acquire K+, Ca2+, and Mg2+, but also maintained higher K+:Na+ ratios in the leaves and lower Ca2+:Mg2+ ratios than non-mycorrhizal seedlings during salt stress. These results suggest that the salt tolerance of E. angustifolia seedlings could be enhanced by R. irregularis. The arbuscular mycorrhizal symbiosis could be a promising method to restore and utilize salt-alkaline land in northern China. PMID:29675008
Root growth, secondary root formation and root gravitropism in carotenoid-deficient seedlings of Zea mays L

NASA Technical Reports Server (NTRS)

Ng, Y. K.; Moore, R.

1985-01-01

The effect of ABA on root growth, secondary-root formation and root gravitropism in seedlings of Zea mays was investigated by using Fluridone-treated seedlings and a viviparous mutant, both of which lack carotenoids and ABA. Primary roots of seedlings grown in the presence of Fluridone grew significantly slower than those of control (i.e. untreated) roots. Elongation of Fluridone-treated roots was inhibited significantly by the exogenous application of 1 mM ABA. Exogenous application of 1 micromole and 1 nmole ABA had either no effect or only a slight stimulatory effect on root elongation, depending on the method of application. The absence of ABA in Fluridone-treated plants was not an important factor in secondary-root formation in seedlings less than 9-10 d old. However, ABA may suppress secondary-root formation in older seedlings, since 11-d-old control seedlings had significantly fewer secondary roots than Fluridone-treated seedlings. Roots of Fluridone-treated and control seedlings were graviresponsive. Similar data were obtained for vp-9 mutants of Z. mays, which are phenotypically identical to Fluridone-treated seedlings. These results indicate that ABA is necessary for neither secondary-root formation nor for positive gravitropism by primary roots.
Gravity-regulated formation of the peg in developing cucumber seedlings

NASA Technical Reports Server (NTRS)

Takahashi, H.; Scott, T. K.

1994-01-01

It has been proposed that peg formation in the vascular transition region (TR zone) between the hypocotyl and the root in Cucurbitaceae seedlings is a gravimorphogenetic phenomenon. Initiation of the peg became visible 36 h after imbibition when cucumber (Cucumis sativus L. cv. Burpee Hybrid II) seeds were germinated in a horizontal position at 24 degrees C in the dark. Simultaneously, sedimented amyloplasts (putative statoliths) were apparent in the sheath cells surrounding the vascular strands, and in the cortical cells immediately adjacent to them, in the TR zone. In contrast, the other cortical cells, some of which were destined to develop into the peg, contained amyloplasts which were not sedimented. These results suggest that the graviperception mechanism for peg formation may be like that of statoliths in shoot gravitropism. By 48 h following imbibition, the cells of the TR zone still had sedimented amyloplasts but had lost their sensitivity to gravity, possibly because of their maturation.
Growth and Chemical Responses to CO2 Enrichment Virginia Pine (Pinus Virginiana Mill.) (NDP-009)

DOE Data Explorer

Luxmoore, R. J. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (USA); Norby, R. J. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (USA); O'Neill, E. G. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (USA); Weller, D. G. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (USA); Ells, J. M. [Agricultural Research Service, USDA; North Carolina State University, Raleigh, NC (USA); Rogers, H. H. [Agricultural Research Service, USDA; North Carolina State University, Raleigh, NC (USA)

1985-01-01

From June 28 to October 29 in 1982, Virginia pine seedlings were exposed to elevated CO2 levels in open-top growth chambers at one of four concentrations (75, 150, 300, and 600 ppm above ambient). Plant dry weight; height; stem diameter; and chemical contents of leaf, stem, and root tissues were measured before and after exposure. Soil variables were also characterized. These data illustrate the short-term physical and chemical response of Virginia pine seedlings to elevated levels of CO2. The data are in seven files: initial dry weights before exposure (844 kB), dry weights after exposure (4 kB), major nutrient concentrations after final harvest (12 kB), minor nutrient concentrations after final harvest (17 kB), soil nutrient concentrations after final harvest (4 kB), soil leachate elements after final harvest (5 kB), and soil leachate solutes after final harvest (4 kB).
Tree proximity, soil pathways and common mycorrhizal networks: their influence on the utilization of redistributed water by understory seedlings.

PubMed

Schoonmaker, Amanda L; Teste, François P; Simard, Suzanne W; Guy, Robert D

2007-12-01

Hydraulic redistribution (HR) is a process by which water moves through plant roots from moist to dry soils. An experiment was conducted to quantify the influence of common mycorrhizal networks (CMNs) and proximity to mature HR-source trees on the water relations of surrounding seedlings. Douglas-fir (Pseudotsuga menziesii var glauca (Mirb.) Franco) seedlings were planted at four distances (0.5, 1, 2.5, and 5 m) from six mature Douglas-fir trees, either directly into soil (soil plus CMN pathway) or inside 0.5 microm mesh bags (soil-only pathway). Deuterated water was used to irrigate soil beside mature trees in order to identify different HR water pathways to surrounding seedlings. This was followed by measurements of seedling deuterium enrichment, seedling water potential, soil water potential, gravimetric soil water content, and tree root density surrounding the seedlings. There was no significantly detectable difference in the quantity of HR water transferred to seedlings having access to soil and CMN pathways or soil-only pathways of water movement. Water from the irrigation plot contributed up to 1.4% of the water of Douglas-fir seedlings. Based on the assumption that the only pathway through which seedlings could access irrigation water was through the mature trees, we estimate that as much as 21.6% of the seedling water was supplied by the nearby tree. Seedling water potential was not significantly affected either by proximity to mature trees or pathway, suggesting HR may have compensated for increasing tree competitive effects with proximity. It is also possible that the lack of difference was due to a relatively moist summer. Our results suggest that residual mature trees are potentially important for hydraulic redistribution to regenerating seedlings in harvested dry interior Douglas-fir forests.
Tree fern trunks facilitate seedling regeneration in a productive lowland temperate rain forest.

PubMed

Gaxiola, Aurora; Burrows, Larry E; Coomes, David A

2008-03-01

Seedling regeneration on forest floors is often impaired by competition with established plants. In some lowland temperate rain forests, tree fern trunks provide safe sites on which tree species establish, and grow large enough to take root in the ground and persist. Here we explore the competitive and facilitative effects of two tree fern species, Cyathea smithii and Dicksonia squarrosa, on the epiphytic regeneration of tree species in nutrient-rich alluvial forests in New Zealand. The difficulties that seedlings have in establishing on vertical tree fern trunks were indicated by the following observations. First, seedling abundance was greatest on the oldest sections of tree fern trunks, near the base, suggesting that trunks gradually recruited more and more seedlings over time, but many sections of trunk were devoid of seedlings, indicating the difficulty of establishment on a vertical surface. Second, most seedlings were from small-seeded species, presumably because smaller seeds can easily lodge on tree fern trunks. Deer browsing damage was observed on 73% of epiphytic seedlings growing within 2 m of the ground, whereas few seedlings above that height were browsed. This suggests that tree ferns provide refugia from introduced deer, and may slow the decline in population size of deer-preferred species. We reasoned that tree ferns would compete with epiphytic seedlings for light, because below the tree fern canopy photosynthetically active radiation (PAR) was about 1% of above-canopy PAR. Frond removal almost tripled %PAR on the forest floor, leading to a significant increase in the height growth rate (HGR) of seedlings planted on the forest floor, but having no effects on the HGRs of epiphytic seedlings. Our study shows evidence of direct facilitative interactions by tree ferns during seedling establishment in plant communities associated with nutrient-rich soils.
Inoculation of fumigated nursery beds and containers with arbuscular mycorrhizal products for eastern redcedar production

Treesearch

Michelle M. Cram; Stephen W. Fraedrich

2015-01-01

Commercially available arbuscular mycorrhizal (AM) products were applied at an operational rate to eastern redcedar (Juniperus virginiana L.) nursery beds and containers to evaluate seedling growth and colonization responses. A field study at the Augusta Forestry Center in Crimora, VA, and a companion container study were initiated in the fall of 2012. MycoApplyÂ® Endo...
Returning fire to Ozark Highland forest ecosystems: Effects on advance regeneration

Treesearch

Daniel C. Dey; George Hartman

2005-01-01

In mature forests of the Ozark Highlands, MO, USA, we evaluated fire effects on the survival and growth of tree seedlings and saplings (i.e., advance regeneration), and used this information to develop species-specific models that predict the probability of survival based on initial tree size and number of times burned. A 1000 ha forest area was divided into five units...
Development of a Mixed-Shrub-Planted Ponderosa Pine Communicty on a Poor Site After Site Preparation and Release

Treesearch

Philip M. McDonald

2003-01-01

On a poor site in northern California, a mature brushfield was treated in various ways that left initial density categories of light, medium, and heavy shrubs. Density, foliar cover, and height of seven shrub species (alone and combined) and ponderosa pine seedlings in these categories were quantified from 1967 through 1978. Heretofore, density and development data for...
Lactarius deliciosus and Pinus radiata in New Zealand: towards the development of innovative gourmet mushroom orchards.

PubMed

Guerin-Laguette, Alexis; Cummings, Nicholas; Butler, Ruth Catherine; Willows, Anna; Hesom-Williams, Nina; Li, Shuhong; Wang, Yun

2014-10-01

The cultivation of Lactarius deliciosus (saffron milk cap) in New Zealand began in 2002 when fruiting bodies were produced in an Otago plantation of Pinus radiata seedlings artificially mycorrhized by L. deliciosus. In 2007, 42 P. radiata seedlings mycorrhized by L. deliciosus under controlled conditions were planted in a grass field at Plant and Food Research (Lincoln, Canterbury). The effects of pine bark mulch application and initial degree of mycorrhization of seedlings were examined to determine their influence on tree growth, development of mycorrhizae (i.e. their multiplication on the root system and their degree of branching) and fruiting body production. Mulch application increased tree growth significantly over 4 years. High initial mycorrhization slightly stimulated tree growth over 2 years. The initial degree of mycorrhization was positively, but not strongly, related to the persistence and development of L. deliciosus mycorrhizae and rhizomorphs based on root sample analyses 2 years after planting. However, mulching strongly reduced the proportion of highly branched L. deliciosus mycorrhizae compared with poorly ramified ones. A positive correlation was observed between the fruiting of L. deliciosus and the development of mycorrhizae. Mulching delayed the onset of fruiting body production. In 2010, fruiting bodies were produced only from non-mulched trees with eight of these (38 %) producing a total of 12 fruiting bodies. In 2011, 19 non-mulched trees (90 %) and 9 mulched trees (45 %) produced 143 and 47 fruiting bodies, respectively, totalling 190 fruiting bodies. By 2012, 19 non-mulched trees (90 %) and 13 mulched trees (65 %) produced 333 and 236 fruiting bodies, respectively, totalling 569 fruiting bodies (c. 30 kg). This study presents new information on factors influencing the onset of fruiting and the development of yields in a plantation of P. radiata mycorrhized by L. deliciosus. Projected yields as high as c. 300 kg/ha from the third year of production reiterate the feasibility of farming saffron milk cap in P. radiata plantations in New Zealand. Continued monitoring of this site and development of similar trials will provide important knowledge for the optimisation of yields in commercial saffron milk cap orchards.
Effects of seedling size, El Niño drought, seedling density, and distance to nearest conspecific adult on 6-year survival of Ocotea whitei seedlings in Panamá.

PubMed

Gilbert, Gregory S; Harms, Kyle E; Hamill, David N; Hubbell, Stephen P

2001-05-01

We present an analysis of the long-term survival of two cohorts of seedlings of the tropical canopy tree Ocotea whitei (Lauraceae) on a 1-ha plot of mature, lowland moist forest on Barro Colorado Island, Panamá. In 1980, we counted an even-aged cohort of seedlings that germinated in 1979, then measured and tagged survivors in 1981. We also measured and tagged a second, smaller cohort of seedlings that germinated in 1981. We followed the subsequent survival of all seedlings through 1985. Seedling mortality was phenotypically, temporally, and spatially non-random. Important correlates of non-random mortality included: (1) seedling size and age, (2) an El Niño drought, and (3) biotic neighborhood. Larger and older seedlings survived better than smaller and younger seedlings, respectively, and the El Niño-related drought of 1982-1983 was associated with elevated mortality rates. Seedling density, which was strongly correlated with the proximity to the nearest conspecific adult, increased mortality. The observed mortality patterns suggest that processes consistent with the Janzen-Connell hypothesis operate during the recruitment phase of O. whitei population dynamics. However, the processes causing the observed density- and distance-dependent mortality may vary with factors such as total seed number, seedling size, and climatic variation, making it difficult to determine whether time-integrated seedling-to-adult spacing mechanisms other than self-thinning operate on a given plant population. After 6 years in the hectare studied, survivors remained densest and most numerous underneath the adult trees. We conclude that only long-term demographic data, collected at a variety of scales on a variety of species, will ultimately answer the question: do Janzen-Connell effects contribute substantially to structuring tropical forests?
The role of genetic and chemical variation of Pinus sylvestris seedlings in influencing slug herbivory.

PubMed

O'Reilly-Wapstra, Julianne M; Iason, Glenn R; Thoss, Vera

2007-05-01

This study investigated the genetic and chemical basis of resistance of Pinus sylvestris seedlings to herbivory by a generalist mollusc, Arion ater. Using feeding trials with captive animals, we examined selective herbivory by A. ater of young P. sylvestris seedlings of different genotypes and correlated preferences with seedling monoterpene levels. We also investigated the feeding responses of A. ater to artificial diets laced with two monoterpenes, Delta(3)-carene and alpha-pinene. Logistic regression indicated that two factors were the best predictors of whether seedlings in the trial would be consumed. Individual slug variation (replicates) was the most significant factor in the model; however, alpha-pinene concentration (also representing beta-pinene, Delta(3)-carene and total monoterpenes due to multicollinearity) of needles was also a significant factor. While A. ater did not select seedlings on the basis of family, seedlings not eaten were significantly higher in levels of alpha-pinene compared to seedlings that were consumed. We also demonstrated significant genetic variation in alpha-pinene concentration of seedlings between different families of P. sylvestris. Nitrogen and three morphological seedling characteristics (stem length, needle length and stem diameter) also showed significant genetic variation between P. sylvestris families. Artificial diets laced with high (5 mg g(-1) dry matter) quantities of either Delta(3)-carene or alpha-pinene, were eaten significantly less than control diets with no added monoterpenes, supporting the results of the seedling feeding trial. This study demonstrates that A. ater selectively feed on P. sylvestris seedlings and that this selection is based, in part, on the monoterpene concentration of seedlings. These results, coupled with significant genetic variation in alpha-pinene concentration of seedlings and evidence that slug herbivory is detrimental to P. sylvestris fitness, are discussed as possible evidence for A. ater as a selective force on the evolution of defensive chemistry in P. sylvestris.
DOE Office of Scientific and Technical Information (OSTI.GOV)

Schuman, G.E.; Stahl, P.D.; Williams, S.E.

Reestablishment of Wyoming big sagebrush (Artemisia tridentata ssp. wyomingensis) on mined lands has been difficult in the past even though it is widespread in the western US. Its reestablishment on mined lands has recently become law where wildlife is one of the post-mining land uses and it represented the primary premining shrub species. One hypothesis thought to contribute to its difficult reestablishment is the reduce lack of mycorrhizae inoculum present in the disturbed topsoil and the resulting effect on the seedling`s ability to extract water from the soil under the arid/semiarid climate of this region. A greenhouse study was conductedmore » to evaluate the effect of mycorrhizae on sagebrush seedling water stress tolerance. Seedling ages evaluated ranged from 30 to 150 days. Seedling survival was greater for mycorrhizal seedlings compared to non-mycorrhizal seedlings when soil moisture tension was {minus}2.5 to {minus}3.8 MPa. At all ages, the degree of soil dryness necessary to cause sagebrush seedling mortality was significantly greater for mycorrhizal than non-mycorrhizal seedlings. Seedling age and mycorrhizal infection exhibited a significant statistical interaction; suggesting that as the sagebrush seedling aged, the benefits of arbuscular mycorrhizae (AM) increased the plants water stress tolerance. These findings lead the authors to conclude that topsoil management that prevents/reduces the loss of AM inoculum in the topsoil will significantly enhance the success of sagebrush establishment on mined lands.« less
Historical forest seedling production in the southern United States: 2008 to 2009 planting season

Treesearch

Scott A. Enebak

2011-01-01

Seedling production across the southern US for the 2008 to 2009 planting season was 1.05 billion seedlings, a decrease of 53.6 million (5%) from the 2007 to 2008 planting season. The vast majority (90%) of reduction in conifer seedling production from 2008 was bareroot loblolly (Pinus taeda) and slash (P. elliottii) pine. Hardwoods were about 1% of regional seedling...
Effects of Lifting Method, Seedling Size, and Herbaceous Weed Control on First-Year Growth of Loblolly Pine Seedlings

Treesearch

Jason P. Reynolds; Thomas A. Greene; John R. Britt

2002-01-01

In fall, 1999, an experiment was installed to measure the effects and interactions of lifting method, seedling size, and weed competition on growth of loblolly pine (P. teada) seedlings during the first two growing seasons. Loblolly pine seedlings grown at two bed densities and lifted either by hand or machine were planted in southwestern Georgia...
UV-B inhibition of hypocotyl growth in etiolated Arabidopsis thaliana seedlings is a consequence of cell cycle arrest initiated by photodimer accumulation

PubMed Central

Biever, Jessica J.; Brinkman, Doug; Gardner, Gary

2014-01-01

Ultraviolet (UV) radiation is an important constituent of sunlight that determines plant morphology and growth. It induces photomorphogenic responses but also causes damage to DNA. Arabidopsis mutants of the endonucleases that function in nucleotide excision repair, xpf-3 and uvr1-1, showed hypersensitivity to UV-B (280–320nm) in terms of inhibition of hypocotyl growth. SOG1 is a transcription factor that functions in the DNA damage signalling response after γ-irradiation. xpf mutants that carry the sog1-1 mutation showed hypocotyl growth inhibition after UV-B irradiation similar to the wild type. A DNA replication inhibitor, hydroxyurea (HU), also inhibited hypocotyl growth in etiolated seedlings, but xpf-3 was not hypersensitive to HU. UV-B irradiation induced accumulation of the G2/M-specific cell cycle reporter construct CYCB1;1-GUS in wild-type Arabidopsis seedlings that was consistent with the expected accumulation of photodimers and coincided with the time course of hypocotyl growth inhibition after UV-B treatment. Etiolated mutants of UVR8, a recently described UV-B photoreceptor gene, irradiated with UV-B showed inhibition of hypocotyl growth that was not different from that of the wild type, but they lacked UV-B-specific expression of chalcone synthase (CHS), as expected from previous reports. CHS expression after UV-B irradiation was not different in xpf-3 compared with the wild type, nor was it altered after HU treatment. These results suggest that hypocotyl growth inhibition by UV-B light in etiolated Arabidopsis seedlings, a photomorphogenic response, is dictated by signals originating from UV-B absorption by DNA that lead to cell cycle arrest. This process occurs distinct from UVR8 and its signalling pathway responsible for CHS induction. PMID:24591052
Evaluating nurse plants for restoring native woody species to degraded subtropical woodlands.

PubMed

Yelenik, Stephanie G; DiManno, Nicole; D'Antonio, Carla M

2015-01-01

Harsh habitats dominated by invasive species are difficult to restore. Invasive grasses in arid environments slow succession toward more desired composition, yet grass removal exacerbates high light and temperature, making the use of "nurse plants" an appealing strategy. In this study of degraded subtropical woodlands dominated by alien grasses in Hawai'i, we evaluated whether individuals of two native (Dodonaea viscosa, Leptocophylla tameiameia) and one non-native (Morella faya) woody species (1) act as natural nodes of recruitment for native woody species and (2) can be used to enhance survivorship of outplanted native woody species. To address these questions, we quantified the presence and persistence of seedlings naturally recruiting beneath adult nurse shrubs and compared survival and growth of experimentally outplanted seedlings of seven native woody species under the nurse species compared to intact and cleared alien-grass plots. We found that the two native nurse shrubs recruit their own offspring, but do not act as establishment nodes for other species. Morella faya recruited even fewer seedlings than native shrubs. Thus, outplanting will be necessary to increase abundance and diversity of native woody species. Outplant survival was the highest under shrubs compared to away from them with few differences between nurse species. The worst habitat for native seedling survival and growth was within the unmanaged invasive grass matrix. Although the two native nurse species did not differentially affect outplant survival, D. viscosa is the most widespread and easily propagated and is thus more likely to be useful as an initial nurse species. The outplanted species showed variable responses to nurse habitats that we attribute to resource requirements resulting from their typical successional stage and nitrogen fixation capability.

Antioxidant Enzyme Activities and Secondary Metabolite Profiling of Oil Palm Seedlings Treated with Combination of NPK Fertilizers Infected with Ganoderma boninense.

PubMed

Sahebi, Mahbod; Hanafi, Mohamed M; Mohidin, Hasmah; Rafii, M Y; Azizi, Parisa; Idris, Abu Seman; Fariz, A; Abiri, Rambod; Taheri, Sima; Moradpoor, Mehdi

2018-01-01

Oil palm ( Elaeis guineensis Jacq) is one of the major sources of edible oil. Reducing the effect of Ganoderma, main cause of basal stem rot (BSR) on oil palm, is the main propose of this study. Understanding the oil palm defense mechanism against Ganoderma infection through monitoring changes in the secondary metabolite compounds levels before/after infection by Ganoderma under different fertilizing treatment is required. Oil palm requires macro- and microelements for growth and yield. Manipulating the nutrient for oil palm is a method to control the disease. The 3-4-month-old oil palm seedlings were given different macronutrient treatments to evaluate induction of defense related enzymes and production of secondary metabolite compounds in response to G. boninense inoculation. The observed trend of changes in the infected and uninfected seedlings was a slightly higher activity for β -1,3-glucanases, chitinase, peroxidase, and phenylalanine ammonia-lyase during the process of pathogenesis. It was found that PR proteins gave positive response to the interaction between oil palm seedlings and Ganoderma infection. Although the responses were activated systematically, they were short-lasting as the changes in enzymes activities appeared before the occurrence of visible symptoms. Effect of different nutrients doses was obviously observed among the results of the secondary metabolite compounds. Many identified/unidentified metabolite compounds were presented, of which some were involved in plant cell defense mechanism against pathogens, mostly belonging to alkaloids with bitter-tasting nitrogenous-compounds, and some had the potential to be used as new markers to detect basal stem rot at the initial step of disease.
Novel software for analysis of root gravitropism: comparative response patterns of Arabidopsis wild-type and axr1 seedlings

NASA Technical Reports Server (NTRS)

Ishikawa, H.; Evans, M. L.

1997-01-01

In an earlier study (Evans, Ishikawa & Estelle 1994, Planta 194, 215-222) we used a video digitizer system to compare the kinetics of auxin action on root elongation in wild-type seedlings and seedlings of auxin response mutants of Arabidopsis thaliana (L.) Heynh. We have since modified the system software to allow determination of elongation on opposite sides of vertical or gravistimulated roots and to allow continuous measurement of the angle of orientation of sequential subsections of the root during the response. We used this technology to compare the patterns of differential growth that generate curvature in roots of the Columbia ecotype and in the mutants axr1-3, axr1-12 and axr2, which show reduced gravitropic responsiveness and reduced sensitivity to inhibition by auxin. The pattern of differential growth during gravitropism differed in roots of wild-type and axr1 seedlings. In wild-type roots, initial curvature resulted from differential inhibition of elongation in the distal elongation zone (DEZ). This was followed by an acceleration of elongation along the top side of the DEZ. In roots of axr1-3, curvature resulted from differential stimulation of elongation whereas in roots of axr1-12 the response was variable. Roots of axr2 did not exhibit gravitropic curvature. The observation that the pattern of differential growth causing curvature is dramatically altered by a change in sensitivity to auxin is consistent with the classical Cholodny-Went theory of gravitropism which maintains that differential growth patterns induced by gravistimulation are mediated primarily by gravi-induced shifts in auxin distribution. The new technology introduced with this report allows automated determination of stimulus response patterns in the small but experimentally popular roots of Arabidopsis.
Sudden changes in environmental conditions do not increase invasion risk in grassland

NASA Astrophysics Data System (ADS)

Ruprecht, Eszter; Fenesi, Annamária; Nijs, Ivan

2013-02-01

After direct habitat transformation, biological invasions are considered to be the second most important threat to biodiversity. A better understanding of the factors affecting invasion success in new areas is crucial, and may provide insight into potential control actions. We hypothesized that invasion risk increases in habitats undergoing a sudden change in the disturbance regime or environmental conditions. For testing this assumption we initiated a seed sowing experiment while introducing two novel treatments, mowing twice and fertilizer application, in two grassland sites (one dryer and one mesic) in Romania. The seeds of two invasive species, Solidago canadensis and Rudbeckia laciniata, and two resident natives of similar seed sizes, life-forms and strategies were sowed in treated and control plots, and seed germination, seedling establishment and growth were followed during four months. Contrary to our expectations, there was no difference in the treatment effects on seed germination and seedling establishment between species, while there was on seedling vigour of the larger seeded species in the dryer grassland site, where the native had a higher performance especially in increased nutrient conditions. Indifferently from applied treatments, invasive species had greater cumulative germination in the mesic site, while natives were far more successful in seedling establishment in the drier site. At the same time, seed size was found to be a very important factor explaining germination and establishment success, with large seeded species outperforming small seeded species in any circumstances. Our results call the attention upon management interventions in mesic, productive grassland sites opening colonization windows for the recruitment of those invasive species of which ecological requirements correspond to local environmental conditions.
Antioxidant Enzyme Activities and Secondary Metabolite Profiling of Oil Palm Seedlings Treated with Combination of NPK Fertilizers Infected with Ganoderma boninense

PubMed Central

Mohidin, Hasmah; Idris, Abu Seman; Fariz, A.; Abiri, Rambod; Taheri, Sima; Moradpoor, Mehdi

2018-01-01

Oil palm (Elaeis guineensis Jacq) is one of the major sources of edible oil. Reducing the effect of Ganoderma, main cause of basal stem rot (BSR) on oil palm, is the main propose of this study. Understanding the oil palm defense mechanism against Ganoderma infection through monitoring changes in the secondary metabolite compounds levels before/after infection by Ganoderma under different fertilizing treatment is required. Oil palm requires macro- and microelements for growth and yield. Manipulating the nutrient for oil palm is a method to control the disease. The 3-4-month-old oil palm seedlings were given different macronutrient treatments to evaluate induction of defense related enzymes and production of secondary metabolite compounds in response to G. boninense inoculation. The observed trend of changes in the infected and uninfected seedlings was a slightly higher activity for β-1,3-glucanases, chitinase, peroxidase, and phenylalanine ammonia-lyase during the process of pathogenesis. It was found that PR proteins gave positive response to the interaction between oil palm seedlings and Ganoderma infection. Although the responses were activated systematically, they were short-lasting as the changes in enzymes activities appeared before the occurrence of visible symptoms. Effect of different nutrients doses was obviously observed among the results of the secondary metabolite compounds. Many identified/unidentified metabolite compounds were presented, of which some were involved in plant cell defense mechanism against pathogens, mostly belonging to alkaloids with bitter-tasting nitrogenous-compounds, and some had the potential to be used as new markers to detect basal stem rot at the initial step of disease. PMID:29721500
Evaluating nurse plants for restoring native woody species to degraded subtropical woodlands

USGS Publications Warehouse

Yelenik, Stephanie G.; DiManno, Nicole; D’Antonio, Carla M.

2015-01-01

Harsh habitats dominated by invasive species are difficult to restore. Invasive grasses in arid environments slow succession toward more desired composition, yet grass removal exacerbates high light and temperature, making the use of “nurse plants” an appealing strategy. In this study of degraded subtropical woodlands dominated by alien grasses in Hawai'i, we evaluated whether individuals of two native (Dodonaea viscosa, Leptocophylla tameiameia) and one non-native (Morella faya) woody species (1) act as natural nodes of recruitment for native woody species and (2) can be used to enhance survivorship of outplanted native woody species. To address these questions, we quantified the presence and persistence of seedlings naturally recruiting beneath adult nurse shrubs and compared survival and growth of experimentally outplanted seedlings of seven native woody species under the nurse species compared to intact and cleared alien-grass plots. We found that the two native nurse shrubs recruit their own offspring, but do not act as establishment nodes for other species. Morella faya recruited even fewer seedlings than native shrubs. Thus, outplanting will be necessary to increase abundance and diversity of native woody species. Outplant survival was the highest under shrubs compared to away from them with few differences between nurse species. The worst habitat for native seedling survival and growth was within the unmanaged invasive grass matrix. Although the two native nurse species did not differentially affect outplant survival, D. viscosa is the most widespread and easily propagated and is thus more likely to be useful as an initial nurse species. The outplanted species showed variable responses to nurse habitats that we attribute to resource requirements resulting from their typical successional stage and nitrogen fixation capability.
Effects of seed mass on seedling success in Artocarpus heterophyllus L., a tropical tree species of north-east India

NASA Astrophysics Data System (ADS)

Khan, M. L.

2004-03-01

I examined the effects of seed mass on performance of seedlings of Artocarpus heterophyllus L. (Moraceae), a large evergreen late successional shade-tolerant tree species in three contrasting light conditions. Seed mass varied many fold from 1.5 to 14 g in A. heterophyllus. Germination and germination time showed a significant correlation with seed mass. Germination differed significantly among three light regimes (50%, 25% and 3%). Seed mass and light level significantly affected seedling survival. The seedlings that emerged from large seeds survived better than those from small seeds under all light regimes. Survival of seedlings was maximum in 25% light regime for all seed mass classes but did not differ significantly from that at 50% light regime. Survival was significantly lower in 3% light as compared to 50% and 25% light regimes. Seedling vigor (expressed in terms of seedling height, leaf area and dry weight) was also significantly affected by seed mass and light regimes. Seedlings that emerged from larger seeds and grew under 50% light regime produced the heaviest seedlings, while those resulting from smaller seeds and grown under 3% light regime produced the lightest seedlings. Resprouting capacity of seedlings after clipping was significantly affected by seed mass and light regime. Seedlings emerging from larger seeds were capable of resprouting several times successively. Resprouting was more pronounced under 50% and 25% light regimes as compared to 3% light. Success of A. heterophyllus regeneration appears to be regulated by an interactive effect of seed mass and light regime.
Seed-vectored endophytic bacteria modulate development of rice seedlings.

PubMed

Verma, S K; Kingsley, K; Irizarry, I; Bergen, M; Kharwar, R N; White, J F

2017-06-01

The aim of the present study was to evaluate the effects of the removal of indigenous bacteria from rice seeds on seedling growth and development. Here we report the presence of three indigenous endophytic bacteria in rice seeds that play important roles in modulating seedling development (shoot and root lengths, and formation of root hairs and secondary roots) and defence against pathogens. Seed-associated bacteria were removed using surface sterilization with NaOCl (bleach) followed by antibiotic treatment. When bacteria were absent, growth of seedlings in terms of root hair development and overall seedling size was less than that of seedlings that contained bacteria. Reactive oxygen staining of seedlings showed that endophytic bacteria became intracellular in root parenchyma cells and root hairs. Roots containing endophytic bacteria were seen to stain densely for reactive oxygen, while roots free of bacteria stained lightly for reactive oxygen. Bacteria were isolated and identified as Enterobacter asburiae (VWB1), Pantoea dispersa (VWB2) and Pseudomonas putida (VWB3) by 16S rDNA sequencing. Bacteria were found to produce indole acetic acid (auxins), inhibited the pathogen Fusarium oxysporum and solubilized phosphate. Reinoculation of bacteria onto seedlings derived from surface-disinfected rice and Bermuda grass seeds significantly restored seedling growth and development. Rice seeds harbour indigenous bacterial endophytes that greatly influence seedling growth and development, including root and shoot lengths, root hair formation and disease susceptibility of rice seedlings. This study shows that seeds of rice naturally harbour bacterial endophytes that play key roles in modulation of seedling development. © 2017 The Society for Applied Microbiology.
Chlorophyll fluorescence and CO(2) assimilation of black spruce seedlings following frost in different temperature and light conditions.

PubMed

Lamontagne, M.; Bigras, F. J.; Margolis, H. A.

2000-03-01

Effects of artificial frosts on light-saturated photosynthesis (A(max)) and ground, maximal and variable fluorescence variables (F(o), F(m), and F(v) and F(v)/F(m)) were monitored on 1-year-old foliage of black spruce seedlings (Picea mariana (Mill.) BSP) grown at high (25 degrees C), moderate (15 degrees C) and low (5 degrees C) temperatures and moderate (240 &mgr;mol m(-2) s(-1)) and low (80 &mgr;mol m(-2) s(-1)) irradiances. Photoinhibition of 1-year-old foliage was greater in seedlings grown in moderate light than in seedlings grown in low light. Photoinhibition increased with decreasing growth chamber temperature at both irradiances. Most changes in F(v)/F(m) were caused by changes in F(v). Exposure to -4 degrees C decreased both F(v)/F(m) and A(max) compared with control values. The effect of the -4 degrees C frost treatment was greater in seedlings grown in low light than in seedlings grown in moderate light, probably because seedlings grown in moderate light were already partially photoinhibited before the frost treatment. Following -4 degrees C treatment, neither F(v)/F(m) nor A(max) recovered in seedlings grown in low light. Light-saturated photosynthesis decreased with decreasing growth chamber temperature. Light-saturated photosynthesis was more sensitive to the -3 and -4 degrees C frost treatments in seedlings grown at 25 degrees C than in seedlings grown at 15 and 5 degrees C. The A(max) of seedlings grown at 15 degrees C was sensitive only to the -4 degrees C frost treatment, whereas A(max) of seedlings grown at 5 degrees C was not sensitive to any of the frost treatments. Recovery of A(max) following frost took longer in seedlings grown at high temperatures than in seedlings grown at low temperatures. For seedlings grown at the same temperature but under different irradiances, both A(max) and F(v)/F(m) reflected damage to the photosynthetic system following a moderate frost. However, for seedlings grown at the same irradiance but different temperatures, A(max) provided a more sensitive indicator of frost damage to the photosynthetic system than F(v)/F(m) ratio.
The role of precision agriculture for improved nutrient management on farms.

PubMed

Hedley, Carolyn

2015-01-01

Precision agriculture uses proximal and remote sensor surveys to delineate and monitor within-field variations in soil and crop attributes, guiding variable rate control of inputs, so that in-season management can be responsive, e.g. matching strategic nitrogen fertiliser application to site-specific field conditions. It has the potential to improve production and nutrient use efficiency, ensuring that nutrients do not leach from or accumulate in excessive concentrations in parts of the field, which creates environmental problems. The discipline emerged in the 1980s with the advent of affordable geographic positioning systems (GPS), and has further developed with access to an array of affordable soil and crop sensors, improved computer power and software, and equipment with precision application control, e.g. variable rate fertiliser and irrigation systems. Precision agriculture focusses on improving nutrient use efficiency at the appropriate scale requiring (1) appropriate decision support systems (e.g. digital prescription maps), and (2) equipment capable of varying application at these different scales, e.g. the footprint of a one-irrigation sprinkler or a fertiliser top-dressing aircraft. This article reviews the rapid development of this discipline, and uses New Zealand as a case study example, as it is a country where agriculture drives economic growth. Here, the high yield potentials on often young, variable soils provide opportunities for effective financial return from investment in these new technologies. © 2014 Society of Chemical Industry.
Persistence of Cytosine Methylation of DNA following Fertilisation in the Mouse

PubMed Central

Li, Yan; O'Neill, Chris

2012-01-01

Normal development of the mammalian embryo requires epigenetic reprogramming of the genome. The level of cytosine methylation of CpG-rich (5meC) regions of the genome is a major epigenetic regulator and active global demethylation of 5meC throughout the genome is reported to occur within the first cell-cycle following fertilization. An enzyme or mechanism capable of catalysing such rapid global demethylation has not been identified. The mouse is a widely used model for studying developmental epigenetics. We have reassessed the evidence for this phenomenon of genome-wide demethylation following fertilisation in the mouse. We found when using conventional methods of immunolocalization that 5meC showed a progressive acid-resistant antigenic masking during zygotic maturation which gave the appearance of demethylation. Changing the unmasking strategy by also performing tryptic digestion revealed a persistence of a methylated state. Analysis of methyl binding domain 1 protein (MBD1) binding confirmed that the genome remained methylated following fertilisation. The maintenance of this methylated state over the first several cell-cycles required the actions of DNA methyltransferase activity. The study shows that any 5meC remodelling that occurs during early development is not explained by a global active loss of 5meC staining during the cleavage stage of development and global loss of methylation following fertilization is not a major component of epigenetic reprogramming in the mouse zygote. PMID:22292019
Effect of heat stress on the fertility of male mice in vivo and in vitro.

PubMed

Yaeram, J; Setchell, B P; Maddocks, S

2006-01-01

A study was conducted to determine whether following exposure of male mice to high temperatures, the ability of their spermatozoa to fertilise ova was reduced, especially during the period before the males became completely infertile. Male mice placed in a microclimate chamber at 36 degrees C for two periods, each of 12 h on successive days, were less able to fertilise control females in vivo when mated and, even in those females that became pregnant, litter size was reduced. However, these effects were associated with falls in testis weight and numbers of spermatozoa in the testis and epididymis. To determine whether the effect on fertility was a result of the decreased spermatozoa numbers, spermatozoa were collected from the epididymides of heated and control males. Equal numbers of motile spermatozoa from an unselected sample or those subjected to a swim-up procedure to separate those that were motile from the immotile ones in the sample were then mixed in vitro with oocytes from superovulated normal females. Similar numbers of spermatozoa from both control and heated males bound to the zona pellucida but smaller percentages of the oocytes were fertilised by spermatozoa from the heated males and fewer of these spermatozoa penetrated the ova. The effects were first seen 7 days after the heat exposure and became more obvious after 10 or 14 days.
Life cycle assessment of energy from waste via anaerobic digestion: a UK case study.

PubMed

Evangelisti, Sara; Lettieri, Paola; Borello, Domenico; Clift, Roland

2014-01-01

Particularly in the UK, there is potential for use of large-scale anaerobic digestion (AD) plants to treat food waste, possibly along with other organic wastes, to produce biogas. This paper presents the results of a life cycle assessment to compare the environmental impacts of AD with energy and organic fertiliser production against two alternative approaches: incineration with energy production by CHP and landfill with electricity production. In particular the paper investigates the dependency of the results on some specific assumptions and key process parameters. The input Life Cycle Inventory data are specific to the Greater London area, UK. Anaerobic digestion emerges as the best treatment option in terms of total CO2 and total SO2 saved, when energy and organic fertiliser substitute non-renewable electricity, heat and inorganic fertiliser. For photochemical ozone and nutrient enrichment potentials, AD is the second option while incineration is shown to be the most environmentally friendly solution. The robustness of the model is investigated with a sensitivity analysis. The most critical assumption concerns the quantity and quality of the energy substituted by the biogas production. Two key issues affect the development and deployment of future anaerobic digestion plants: maximising the electricity produced by the CHP unit fuelled by biogas and to defining the future energy scenario in which the plant will be embedded. Copyright © 2013 Elsevier Ltd. All rights reserved.
Rosmarinic acid improves function and in vitro fertilising ability of boar sperm after cryopreservation.

PubMed

Luño, Victoria; Gil, Lydia; Olaciregui, Maite; González, Noelia; Jerez, Rodrigo Alberto; de Blas, Ignacio

2014-08-01

During cryopreservation, oxidative stress exerts physical and chemical changes on sperm functionality. In the present study we investigated the antioxidant effect of rosmarinic acid (RA) on quality and fertilising ability of frozen-thawed boar spermatozoa. Ejaculates collected from mature boar were cryopreserved in lactose-egg yolk buffer supplemented with different concentrations of RA (0 μM, 26.25 μM, 52.5 μM and 105 μM). Motion parameters, acrosome and plasma membrane integrity, lipoperoxidation levels, DNA oxidative damage (8-hydroxy-2-deoxyguanosine base lesion) and in vitro fertilisation ability were evaluated. Total and progressive motility were significantly higher in experimental extenders with RA than in the control (P<0.05) at 0 and 120 min post-thawing. The plasma and acrosomal membrane integrity were improved by supplementation with 105 μMRA (P<0.05). Negative correlation between RA and malondialdehyde (MDA) concentration were determined (P<0.05). After thawing, the percentage of spermatozoa with oxidised DNA did not differ between extenders, however, at 120 and 240 min post-thawing, the samples supplemented with 105 μMRA showed the lowest DNA oxidation rate (P<0.05). The penetration rate was significantly higher on spermatozoa cryopreserved with 105 μMRA (P<0.05). The results suggest that RA provides a protection for boar spermatozoa against oxidative stress during cryopreservation by their antioxidant properties. Copyright © 2014 Elsevier Inc. All rights reserved.
Effects of local biotic neighbors and habitat heterogeneity on tree and shrub seedling survival in an old-growth temperate forest.

PubMed

Bai, Xuejiao; Queenborough, Simon A; Wang, Xugao; Zhang, Jian; Li, Buhang; Yuan, Zuoqiang; Xing, Dingliang; Lin, Fei; Ye, Ji; Hao, Zhanqing

2012-11-01

Seedling dynamics play a crucial role in determining species distributions and coexistence. Exploring causes of variation in seedling dynamics can therefore provide key insights into the factors affecting these phenomena. We examined the relative importance of biotic neighborhood processes and habitat heterogeneity using survival data for 5,827 seedlings in 39 tree and shrub species over 2 years from an old-growth temperate forest in northeastern China. We found significant negative density-dependence effects on survival of tree seedlings, and limited effects of habitat heterogeneity (edaphic and topographic variables) on survival of shrub seedlings. The importance of negative density dependence on young tree seedling survival was replaced by habitat in tree seedlings ≥ 4 years old. As expected, negative density dependence was more apparent in gravity-dispersed species compared to wind-dispersed and animal-dispersed species. Moreover, we found that a community compensatory trend existed for trees. Therefore, although negative density dependence was not as pervasive as in other forest communities, it is an important mechanism for the maintenance of community diversity in this temperate forest. We conclude that both negative density dependence and habitat heterogeneity drive seedling survival, but their relative importance varies with seedling age classes and species traits.
Allocation strategies of savanna and forest tree seedlings in response to fire and shading: outcomes of a field experiment

NASA Astrophysics Data System (ADS)

Gignoux, Jacques; Konaté, Souleymane; Lahoreau, Gaëlle; Le Roux, Xavier; Simioni, Guillaume

2016-12-01

The forest-savanna ecotone may be very sharp in fire-prone areas. Fire and competition for light play key roles in its maintenance, as forest and savanna tree seedlings are quickly excluded from the other ecosystem. We hypothesized a tradeoff between seedling traits linked to fire resistance and to competition for light to explain these exclusions. We compared growth- and survival-related traits of two savanna and two forest species in response to shading and fire in a field experiment. To interpret the results, we decomposed our broad hypothesis into elementary tradeoffs linked to three constraints, biomass allocation, plant architecture, and shade tolerance, that characterize both savanna and adjacent forest ecosystems. All seedlings reached similar biomasses, but forest seedlings grew taller. Savanna seedlings better survived fire after topkill and required ten times less biomass than forest seedlings to survive. Finally, only savanna seedlings responded to shading. Although results were consistent with the classification of our species as mostly adapted to shade tolerance, competition for light in the open, and fire tolerance, they raised new questions: how could savanna seedlings survive better with a 10-times lower biomass than forest seedlings? Is their shade intolerance sufficient to exclude them from forest understory?
Common arbuscular mycorrhizal networks amplify competition for phosphorus between seedlings and established plants.

PubMed

Merrild, Marie P; Ambus, Per; Rosendahl, Søren; Jakobsen, Iver

2013-10-01

Common mycorrhizal networks (CMNs) influence competition between plants, but reports regarding their precise effect are conflicting. We studied CMN effects on phosphorus (P) uptake and growth of seedlings as influenced by various disruptions of network components. Tomato (Solanum lycopersicon) seedlings grew into established networks of Rhizophagus irregularis and cucumber (Cucumis sativus) in two experiments. One experiment studied seedling uptake of (32)P in the network in response to cutting of cucumber shoots; the other analysed seedling uptake of P and nitrogen (N) in the presence of intact or severed arbuscular mycorrhizal fungus networks and at two soil P concentrations. Pre-established and intact networks suppressed growth of tomato seedlings. Cutting of cucumber shoots mitigated P deficiency symptoms of seedlings, which obtained access to P in the extraradical mycelium and thereby showed improved growth. Solitary seedlings growing in a network patch that had been severed from the CMN also grew much better than seedlings of the corresponding CMN. Interspecific and size-asymmetric competition between plants may be amplified rather than relaxed by CMNs that transfer P to large plants providing most carbon and render small plants P deficient. It is likely that grazing or senescence of the large plants will alleviate the network-induced suppression of seedling growth. © 2013 The Authors. New Phytologist © 2013 New Phytologist Trust.
Modeling of genetic gain for single traits from marker-assisted seedling selection in clonally propagated crops

PubMed Central

Ru, Sushan; Hardner, Craig; Carter, Patrick A; Evans, Kate; Main, Dorrie; Peace, Cameron

2016-01-01

Seedling selection identifies superior seedlings as candidate cultivars based on predicted genetic potential for traits of interest. Traditionally, genetic potential is determined by phenotypic evaluation. With the availability of DNA tests for some agronomically important traits, breeders have the opportunity to include DNA information in their seedling selection operations—known as marker-assisted seedling selection. A major challenge in deploying marker-assisted seedling selection in clonally propagated crops is a lack of knowledge in genetic gain achievable from alternative strategies. Existing models based on additive effects considering seed-propagated crops are not directly relevant for seedling selection of clonally propagated crops, as clonal propagation captures all genetic effects, not just additive. This study modeled genetic gain from traditional and various marker-based seedling selection strategies on a single trait basis through analytical derivation and stochastic simulation, based on a generalized seedling selection scheme of clonally propagated crops. Various trait-test scenarios with a range of broad-sense heritability and proportion of genotypic variance explained by DNA markers were simulated for two populations with different segregation patterns. Both derived and simulated results indicated that marker-based strategies tended to achieve higher genetic gain than phenotypic seedling selection for a trait where the proportion of genotypic variance explained by marker information was greater than the broad-sense heritability. Results from this study provides guidance in optimizing genetic gain from seedling selection for single traits where DNA tests providing marker information are available. PMID:27148453
Soil microbial biomass and community structure affected by repeated additions of sewage sludge in four Swedish long-term field experiments

NASA Astrophysics Data System (ADS)

Börjesson, G.; Kätterer, T.; Kirchmann, H.

2012-04-01

Soil organic matter is a key attribute of soil fertility. The pool of soil organic C can be increased, either by mineral fertilisers or by adding organic amendments such as sewage sludge. Sewage sludge has positive effects on agricultural soils through the supply of organic matter and essential plant nutrients, but sludge may also contain unwanted heavy metals, xenobiotic substances and pathogens. One obvious effect of long-term sewage sludge addition is a decrease in soil pH, caused by N mineralisation followed by nitrification, sulphate formation and presence of organic acids with the organic matter added. The objective of this study was to investigate the effect of sewage sludge on the microbial biomass and community structure. Materials and methods We analysed soil samples from four sites where sewage sludge has been repeatedly applied in long-term field experiments situated in different parts of Sweden; Ultuna (59°49'N, 17°39'E, started 1956), Lanna (58°21'N, 13°06'E, started 1997-98), Petersborg (55°32'N, 13°00'E, started 1981) and Igelösa (55°45'N, 13°18'E, started 1981). In these four experiments, at least one sewage sludge treatment is included in the experimental design. In the Ultuna experiment, all organic fertilisers, including sewage sludge, are applied every second year, corresponding to 4 ton C ha-1. The Lanna experiment has a similar design, with 8 ton dry matter ha-1 applied every second year. Lanna also has an additional treatment in which metal salts (Cd, Cu, Ni and Zn) are added together with sewage sludge. At Petersborg and Igelösa, two levels of sewage sludge (4 or 12 ton dry matter ha-1 every 4th year) are compared with three levels of NPK fertiliser (0 N, ½ normal N and normal N). Topsoil samples (0-20 cm depth) from the four sites were analysed for total C, total N, pH and PLFAs (phospholipid fatty acids). In addition, crop yields were recorded. Results At all four sites, sewage sludge has had a positive effect on crop yields and soil organic matter levels. Correlations between soil organic matter and total PLFA contents showed highly positive correlations at all sites (with R-values between 0.72 and 0.88). To find out whether sewage sludge through its metal impurities could impose stress on the microbial biomass, we compared the correlations between all different fertilisers used and PLFAs. The slopes of these comparisons revealed that sludge did not differ from other fertiliser treatments, which means that our results contrast earlier reports on negative effects of metals in sludge on soil microbes. The microbial community structure, studied with principal component analysis of individual PLFAs, was strongly affected by changes in soil pH, and at those sites where sewage sludge had caused a low pH, Gram-positive bacteria were more dominant than in the other treatments. However, differences in community structure were larger between sites than between the treatments investigated in this study, thus indicating that the original soil properties were more important for the microbial community structure than the fertiliser treatments.
Kinetics for phototropic curvature by etiolated seedlings of Arabidopsis thaliana

NASA Technical Reports Server (NTRS)

Orbovic, V.; Poff, K. L.

1991-01-01

An infrared-imaging system has been used to study the influence of gravity on the kinetics of first positive phototropism. The development of phototropic curvature of etiolated seedlings of Arabidopsis thaliana was measured in the absence of visible radiation. Following a pulse of blue light, stationary seedlings curved to a maximum of approximately 16 degrees about 80 minutes after stimulation. The seedlings then curved upward again or straightened by about 6 degrees during the subsequent 100 minutes. Seedlings rotated on a clinostat reached a similar maximum curvature following photostimulation. These seedlings maintained that curvature for 30 to 40 minutes before subsequently straightening to the same extent as the stationary seedlings. It is concluded that straightening is not a consequence of gravitropism, although gravity has some effect on the phototropism kinetics.
Effect of canopy position on germination and seedling survival of epiphytic bromeliads in a Mexican humid montane forest.

PubMed

Winkler, Manuela; Hülber, Karl; Hietz, Peter

2005-05-01

Seeds of epiphytes must land on branches with suitable substrates and microclimates to germinate and for the resulting seedlings to survive. It is important to understand the fate of seeds and seedlings in order to model populations, but this is often neglected when only established plants are included in analyses. The seeds of five bromeliad species were exposed to different canopy positions in a Mexican montane forest, and germination and early seedling survival were recorded. Additionally, the survival of naturally dispersed seedlings was monitored in a census over 2.5 years. Survival analysis, a procedure rarely used in plant ecology, was used to study the influence of branch characteristics and light on germination and seedling survival in natural and experimental populations. Experimental germination percentages ranged from 7.2 % in Tillandsia deppeana to 33.7 % in T. juncea, but the seeds of T. multicaulis largely failed to germinate. Twenty months after exposure between 3.5 and 9.4 % of the seedlings were still alive. There was no evidence that canopy position affected the probability of germination, but time to germination was shorter in less exposed canopy positions indicating that higher humidity accelerates germination. More experimental seedlings survived when canopy openness was high, whereas survival in census-seedlings was influenced by moss cover. While mortality decreased steadily with age in juveniles of the atmospheric Tillandsia, in the more mesomorphic Catopsis sessiliflora mortality increased dramatically in the dry season. Seedling mortality, rather than the failure to germinate, accounts for the differential distribution of epiphytes within the canopy studied. With few safe sites to germinate and high seedling mortality, changes of local climate may affect epiphyte populations primarily through their seedling stage.

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