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1

Modulation of germination, elongation growth and flowering time in plants  

E-print Network

Modulation of germination, elongation growth and flowering time in plants Reference Number B69259 Background · The present invention relates to a method for modulating plant developmen- tal processes that have direct impact on plant growth and yield. · Identified genes act downstream from the gibberelic

2

Earthworm-mediated maternal effects on seed germination and seedling growth in three annual plants  

Microsoft Academic Search

Many ecological studies have pointed out maternal effects in plants and shown that plant maternal environment influences germination of their seed and subsequent seedling growth. However, few have tested for maternal effects induced by soil macroorganisms. We tested whether two earthworm species (Aporrectodea caliginosa and Lumbricus terrestris) trigger such maternal effects on seed germination and seedling growth of three plant

Kam-Rigne Laossi; Diana-Cristina Noguera; Sbastien Barot

2010-01-01

3

Effect of plant growth hormones and abiotic stresses on germination, growth and phosphatase activities in Sorghum bicolor (L.) Moench seeds  

Microsoft Academic Search

Phosphatases are widely found in plants having intracellular and extracellular activities. Phosphatases are believed to be important for phosphorous scavenging and remobilization in plants, but its role in adaptation to abiotic stresses and growth hormones at germination level has not been critically evaluated. To address this issue, the effect of ABA, GA3, NaCl and drought on germination, growth, acid and

Arun Dev Sharma; Meenu Thakur; Meenakshi Rana; Kuldeep Singh

4

Phytotoxic activity of Ocimum tenuiflorum extracts on germination and seedling growth of different plant species.  

PubMed

Phytotoxic activity of Ocimum tenuiflorum (Lamiaceae) plant extracts was investigated against the germination and seedling growth of cress (Lepidium sativum), lettuce (Lactuca sativa), alfalfa (Medicago sativa), Italian ryegrass (Lolium multiflorum), barnyard grass (Echinochloa crus-galli), and timothy (Phleum pratense) at four different concentrations. The plant extracts at concentrations greater than 30?mg dry weight equivalent extract mL(-1) reduced significantly the total germination percent (GP), germination index (GI), germination energy (GE), speed of emergence (SE), seedling vigour index (SVI), and coefficient of the rate of germination (CRG) of all test species except barnyard grass and GP of lettuce. In contrast, time required for 50% germination (T 50) and mean germination time (MGT) were increased at the same or higher than this concentration. The increasing trend of T 50 and MGT and the decreasing trend of other indices indicated a significant inhibition or delay of germination of the test species by O. tenuiflorum plant extracts and vice versa. In addition, the shoot and root growth of all test species were significantly inhibited by the extracts at concentrations greater than 10?mg dry weight equivalent extract mL(-1). The I 50 values for shoot and root growth were ranged from 26 to 104?mg dry weight equivalent extract mL(-1). Seedling growth was more sensitive to the extracts compared to seed germination. Results of this study suggest that O. tenuiflorum plant extracts have phytotoxic properties and thus contain phytotoxic substances. Isolation and characterization of those substances from this plant may act as a tool for new natural, biodegradable herbicide development to control weeds. PMID:25032234

Islam, A K M Mominul; Kato-Noguchi, Hisashi

2014-01-01

5

Seed storage conditions change the germination pattern of clonal growth plants in Mediterranean salt marshes.  

PubMed

The effect of salinity level and extended exposure to different salinity and flooding conditions on germination patterns of three salt-marsh clonal growth plants (Juncus subulatus, Scirpus litoralis, and S. maritimus) was studied. Seed exposure to extended flooding and saline conditions significantly affected the outcome of the germination process in a different, though predictable, way for each species, after favorable conditions for germination were restored. Tolerance of the germination process was related to the average salinity level measured during the growth/germination season at sites where established individuals of each species dominated the species cover. No relationship was found between salinity tolerance of the germination process and seed response to extended exposure to flooding and salinity conditions. The salinity response was significantly related to the conditions prevailing in the habitats of the respective species during the unfavorable (nongrowth/nongermination) season. Our results indicate that changes in salinity and hydrology while seeds are dormant affect the outcome of the seed-bank response, even when conditions at germination are identical. Because these environmental-history-dependent responses differentially affect seed germination, seedling density, and probably sexual recruitment in the studied and related species, these influences should be considered for wetland restoration and management. PMID:21646131

Espinar, Jos L; Garca, Luis V; Clemente, Luis

2005-07-01

6

[Allelopathic effects of Artemisia frigida on three Poaceae plants seed germination and seedling growth].  

PubMed

Aqueous extracts of Artemisia frigida leaf and stem and soils beneath A. frigida were used to test their allelopathic effects on the seed germination and seedling growth of three Poaceae plants (Leymus chinensis, Stipa krylovii, and Cleistogenes squarrosa) on Leymus chinensis grassland. The aqueous extracts of A. frigida leaf and stem decreased the seed germination index of test plants and prolonged their seed germination time, and inhibited the shoot growth of the three plants and the root growth of S. krylovii. The aqueous extracts at concentration > or = 0.075 g x ml(-1) presented a strong inhibition on the root growth of L. chinensis, while those at concentration < or = 0.05 g x ml(-1) had less effects. For the root growth of C. squarrosa, the aqueous extracts showed a "low-promotion and high-inhibition effect". Under the effects of A. frigida soil, the seedling growth of test plants was inhibited. The sensitivity of test plants to the allelopathic effects of A. frigida was in the order of S. krylovii > L. chinense > C. squarrosa, with a higher sensitivity of root growth than shoot growth. PMID:20879526

Li, Xue-feng; Wang, Jian; Xu, Wen-bo; Wang, Kun

2010-07-01

7

Effects of Silver Nanoparticle Exposure on Germination and Early Growth of Eleven Wetland Plants  

PubMed Central

The increasing commercial production of engineered nanoparticles (ENPs) has led to concerns over the potential adverse impacts of these ENPs on biota in natural environments. Silver nanoparticles (AgNPs) are one of the most widely used ENPs and are expected to enter natural ecosystems. Here we examined the effects of AgNPs on germination and growth of eleven species of common wetland plants. We examined plant responses to AgNP exposure in simple pure culture experiments (direct exposure) and for seeds planted in homogenized field soils in a greenhouse experiment (soil exposure). We compared the effects of two AgNPs20-nm polyvinylpyrrolidine-coated silver nanoparticles (PVP-AgNPs) and 6-nm gum arabic coated silver nanoparticles (GA-AgNPs)to the effects of AgNO3 exposure added at equivalent Ag concentrations (1, 10 or 40 mg Ag L?1). In the direct exposure experiments, PVP-AgNP had no effect on germination while 40 mg Ag L?1 GA-AgNP exposure significantly reduced the germination rate of three species and enhanced the germination rate of one species. In contrast, 40 mg Ag L?1 AgNO3 enhanced the germination rate of five species. In general root growth was much more affected by Ag exposure than was leaf growth. The magnitude of inhibition was always greater for GA-AgNPs than for AgNO3 and PVP-AgNPs. In the soil exposure experiment, germination effects were less pronounced. The plant growth response differed by taxa with Lolium multiflorum growing more rapidly under both AgNO3 and GA-AgNP exposures and all other taxa having significantly reduced growth under GA-AgNP exposure. AgNO3 did not reduce the growth of any species while PVP-AgNPs significantly inhibited the growth of only one species. Our findings suggest important new avenues of research for understanding the fate and transport of NPs in natural media, the interactions between NPs and plants, and indirect and direct effects of NPs in mixed plant communities. PMID:23091638

Yin, Liyan; Colman, Benjamin P.; McGill, Bonnie M.; Wright, Justin P.; Bernhardt, Emily S.

2012-01-01

8

Effects of silver nanoparticle exposure on germination and early growth of eleven wetland plants.  

PubMed

The increasing commercial production of engineered nanoparticles (ENPs) has led to concerns over the potential adverse impacts of these ENPs on biota in natural environments. Silver nanoparticles (AgNPs) are one of the most widely used ENPs and are expected to enter natural ecosystems. Here we examined the effects of AgNPs on germination and growth of eleven species of common wetland plants. We examined plant responses to AgNP exposure in simple pure culture experiments (direct exposure) and for seeds planted in homogenized field soils in a greenhouse experiment (soil exposure). We compared the effects of two AgNPs-20-nm polyvinylpyrrolidine-coated silver nanoparticles (PVP-AgNPs) and 6-nm gum arabic coated silver nanoparticles (GA-AgNPs)-to the effects of AgNO(3) exposure added at equivalent Ag concentrations (1, 10 or 40 mg Ag L(-1)). In the direct exposure experiments, PVP-AgNP had no effect on germination while 40 mg Ag L(-1) GA-AgNP exposure significantly reduced the germination rate of three species and enhanced the germination rate of one species. In contrast, 40 mg Ag L(-1) AgNO(3) enhanced the germination rate of five species. In general root growth was much more affected by Ag exposure than was leaf growth. The magnitude of inhibition was always greater for GA-AgNPs than for AgNO(3) and PVP-AgNPs. In the soil exposure experiment, germination effects were less pronounced. The plant growth response differed by taxa with Lolium multiflorum growing more rapidly under both AgNO(3) and GA-AgNP exposures and all other taxa having significantly reduced growth under GA-AgNP exposure. AgNO(3) did not reduce the growth of any species while PVP-AgNPs significantly inhibited the growth of only one species. Our findings suggest important new avenues of research for understanding the fate and transport of NPs in natural media, the interactions between NPs and plants, and indirect and direct effects of NPs in mixed plant communities. PMID:23091638

Yin, Liyan; Colman, Benjamin P; McGill, Bonnie M; Wright, Justin P; Bernhardt, Emily S

2012-01-01

9

Increased growth and germination success in plants following hydrogen sulfide administration.  

PubMed

This study presents a novel way of enhancing plant growth through the use of a non-petroleum based product. We report here that exposing either roots or seeds of multicellular plants to extremely low concentrations of dissolved hydrogen sulfide at any stage of life causes statistically significant increases in biomass including higher fruit yield. Individual cells in treated plants were smaller (~13%) than those of controls. Germination success and seedling size increased in, bean, corn, wheat, and pea seeds while time to germination decreases. These findings indicated an important role of H2S as a signaling molecule that can increase the growth rate of all species yet tested. The increased crop yields reported here has the potential to effect the world's agricultural output. PMID:23614010

Dooley, Frederick D; Nair, Suven P; Ward, Peter D

2013-01-01

10

A Simple and Versatile 2-Dimensional Platform to Study Plant Germination and Growth under Controlled Humidity  

PubMed Central

We describe a simple, inexpensive, but remarkably versatile and controlled growth environment for the observation of plant germination and seedling root growth on a flat, horizontal surface over periods of weeks. The setup provides to each plant a controlled humidity (between 56% and 91% RH), and contact with both nutrients and atmosphere. The flat and horizontal geometry of the surface supporting the roots eliminates the gravitropic bias on their development and facilitates the imaging of the entire root system. Experiments can be setup under sterile conditions and then transferred to a non-sterile environment. The system can be assembled in 1-2 minutes, costs approximately 8.78$ per plant, is almost entirely reusable (0.43$ per experiment in disposables), and is easily scalable to a variety of plants. We demonstrate the performance of the system by germinating, growing, and imaging Wheat (Triticum aestivum), Corn (Zea mays), and Wisconsin Fast Plants (Brassica rapa). Germination rates were close to those expected for optimal conditions. PMID:24806462

Sizmur, Tom; Lind, Kara R.; Benomar, Saida; VanEvery, Hannah; Cademartiri, Ludovico

2014-01-01

11

Morphology, Germination and early Seedling Growth in Phaseolus mungo L. with Reference to the Influence of Various Plant Growth Substances  

Microsoft Academic Search

The paper presents the results of studies on morphological characters, seed germination and the influence of different concentrations of plant growth substances on Phaseolus mungo including the comparative growth patterns of the seedlings. Seeds were pre-soaked for 24h under the various concentrations (0.1, 1.0 and 10 ppm) of GA 3, IBA and NAA. Soaked seeds were arranged in sterilized petriplates

J. S. Chauhan; Anoop Badoni; N. Indrakumar Singh; Seema Ali

2009-01-01

12

Phytotoxicity of hexachlorocyclohexane: Effect on germination and early growth of different plant species.  

PubMed

The aim of the present study was to select candidate plant species for phytoremediation of soils contaminated with hexachlorocyclohexane (HCH). For this purpose, an experiment was carried out under controlled conditions of germination and growth, with nine plant species of economic and/or agricultural interest, in a soil contaminated with a heterogeneous mixture (at eight different levels of contamination) of the main HCH isomers (alpha-, beta-, gamma- and delta-HCH). The results revealed differences in the plant responses to the control soil and the soils containing HCH. Germination was not as strongly affected as other parameters such as the rate of germination and seedling vigour. In general, all of the species displayed signs of stress in response to the presence of HCH, although to different degrees. Some of the species used in the experiment (Hordeum vulgare L., Brassica sp., Phaseoulus vulgaris L.) were capable of mitigating the negative effects of HCH, and displayed a certain degree of resistance, as their biomass production was not greatly affected by the contaminant. These (tolerant) plants therefore appear to be ideal for phytoremediation purposes. PMID:20172584

Calvelo Pereira, R; Monterroso, C; Macas, F

2010-04-01

13

Effects of diesel and kerosene on germination and growth of coastal wetland plant species.  

PubMed

This study aims to investigate effects of diesel and kerosene on seed germination and seedling growth among coastal wetland plants to select species that can be used for the restoration and revegetation of oil-polluted habitats. Tests on 51 species were performed in Petri dishes containing 0%, 6%, 12%, and 18% diesel, 20%, 40%, and 60% kerosene; each treatment combination was replicated five times with 20 seeds in each Petri dish. All dishes were held in a growth chamber with 20C day of 12h/15C night of 12h in 80% humidity for 20days for calculating the germination percentage, seedling weight, and seedling vitality. The germination percentage of Rumex stenophyllus decreased significantly in diesel and kerosene treatments. The weights of seedlings treated with diesel and kerosene either increased or decreased in comparison with controls depending on the species. Vitality percentage values were high for seedlings of Chenopodium ficifolium. Thus, herbaceous plant responses to oil treatments are species-specific. PMID:25138038

Kim, Kee Dae

2014-11-01

14

Rare earth elements (REEs): effects on germination and growth of selected crop and native plant species.  

PubMed

The phytotoxicity of rare earth elements (REEs) is still poorly understood. The exposure-response relationships of three native Canadian plant species (common milkweed, Asclepias syriaca L., showy ticktrefoil, Desmodium canadense (L.) DC. and switchgrass, Panicum virgatum L.) and two commonly used crop species (radish, Raphanus sativus L., and tomato, Solanum lycopersicum L.) to the REEs lanthanum (La), yttrium (Y) and cerium (Ce) were tested. In separate experiments, seven to eight doses of each element were added to the soil prior to sowing seeds. Effects of REE dose on germination were established through measures of total percent germination and speed of germination; effects on growth were established through determination of above ground biomass. Ce was also tested at two pH levels and plant tissue analysis was conducted on pooled samples. Effects on germination were mostly observed with Ce at low pH. However, effects on growth were more pronounced, with detectable inhibition concentrations causing 10% and 25% reductions in biomass for the two native forb species (A. syriaca and D. canadense) with all REEs and on all species tested with Ce in both soil pH treatments. Concentration of Ce in aboveground biomass was lower than root Ce content, and followed the dose-response trend. From values measured in natural soils around the world, our results continue to support the notion that REEs are of limited toxicity and not considered extremely hazardous to the environment. However, in areas where REE contamination is likely, the slow accumulation of these elements in the environment could become problematic. PMID:23978671

Thomas, Philippe J; Carpenter, David; Boutin, Cline; Allison, Jane E

2014-02-01

15

Environmental effects of nanosilver: impact on castor seed germination, seedling growth, and plant physiology.  

PubMed

Increasing use of nanoparticles in daily products is of great concern today, especially when their positive and negative impact on environment is not known. Hence, in current research, we have studied the impact of silver nanoparticle (AgNPs) and silver nitrate (AgNO3) application on seed germination, root, and shoot length of castor bean, Ricinus communis L. plant. Silver nanoparticles had no significant effects on seedling growth even at higher concentration of 4,000 mg L(-1), while the silver in bulk form as AgNO3 applied on the castor bean seeds inhibited the seed germination. Silver uptake in seedlings of the castor seeds on treatment with both the forms of silver was confirmed through atomic absorption spectroscopy studies. The silver nanoparticle and silver nitrate application to castor seeds also caused an enhanced enzymatic activity of ROS enzymes and phenolic content in castor seedlings. High-performance liquid chromatography analysis of individual phenols indicated enhanced content of parahydroxy benzoic acid. These kinds of studies are of great interest in order to unveil the movement and accumulation of nanoparticles in plant tissues for assessing future applications in the field or laboratory. PMID:23702569

Yasur, Jyothsna; Rani, Pathipati Usha

2013-12-01

16

Role of Substances Formed during Germination in the Growth of Plants  

Microsoft Academic Search

IN this laboratory, v. Hausen1 showed in her doctoral thesis that if the cotyledons of a pea plant are removed after a germination period of five to nine days, and the cotyledonless seedling is transferred into a sterile nutrient solution (the sterile culture system of Virtanen and v. Hausen2), it grows at first poorly and small chlorophyll-containing leaves are formed;

Artturi I. Virtanen; Synnve Saubert-V. Hausen

1949-01-01

17

4. The role of plant growth regulators in the germination of forest tree seeds  

Microsoft Academic Search

To establish a role for PGRs in the germination of forest tree seeds, it must be demonstrated that PGRs are involved in the mechanisms that control the induction of and release from dormancy, and also that these mechanisms are operative in the seeds of woody plants. Four currently known concepts of seed dormancy are reviewed, citing the published evidence relating

C. L. Leadem

1987-01-01

18

In vitro evaluation of germination and growth of five plant species on medium supplemented with hydrocarbons associated with contaminated soils.  

PubMed

The effect of a hydrocarbon mixture (HCM) of three polycyclic aromatic hydrocarbons (PAH) and Maya crude oil on germination, growth and survival of four grasses (Bouteloua curtipendula, Cenchrus ciliaris, Echinochloa crusgalli and Rhynchelytrum repens) was studied and compared to a control (Festuca arundinacea) under in vitro conditions. The species were cultured on MS medium with different HCM initial concentrations. Germination was not affected for any assayed concentration; however, the length of the stems and roots decreased when HCM increased and the survival of the four species also diminished. Except for F. arundinacea, a direct link between hydrocarbon concentration and plant survival was observed. In vitro studies are clean and easy to handle techniques allowing isolation of the plant activity from that derived from associations with microorganisms in non-sterile cultures. To our knowledge, this is the first work towards phytoremediation assisted by in vitro plant cultivation. PMID:18222086

Reynoso-Cuevas, L; Gallegos-Martnez, M E; Cruz-Sosa, F; Gutirrez-Rojas, M

2008-09-01

19

Cadmium-induced stress on the seed germination and seedling growth of Brassica napus L., and its alleviation through exogenous plant growth regulators  

Microsoft Academic Search

Because of its prolific growth, oilseed rape (Brassica napus L.) can be grown advantageously for phytoremediation of the lands contaminated by industrial wastes. Therefore, toxic effect\\u000a of cadmium on the germination of oilseed rape, the capability of plants for cadmium phytoextraction, and the effect of exogenous\\u000a application of plant growth regulators to mitigate phytotoxicity of cadmium were investigated. For the

Huabing Meng; Shujin Hua; Imran Haider Shamsi; Ghulam Jilani; Yuanlong Li; Lixi Jiang

2009-01-01

20

THE EFFECTS OF PRETREATMENTS OF SOME PLANT GROWTH REGULATORS ON GERMINATION AND SEEDLING GROWTH OF RADISH SEEDS UNDER SALINE CONDITIONS  

Microsoft Academic Search

The effects of gibberellic acid, kinetin, benzyladenine, ethylene, triacontanol, 24-epibrassinolide and polyamines (cadaverine, putrescine, spermidine, spermine), alone or in combinations, on seed germination and seedling growth (fresh weight, hypocotyl percentage, radicle and hypocotyl elongation) of radish under saline conditions were studied. Although many of the growth regulator pretreatments alone carried out in overcoming of the negative effect of 0.25 and

Kudret KABAR

21

In vitro: Response of plant growth regulators and antimalformins on conidia germination of Fusarium mangiferae and incidence of mango malformation.  

PubMed

Mango malformation is the most important and threatening disease of recent times, primarily because of persistent lacuna in complete understanding of its nature. Diverse Fusarium spp, including F. mangiferae, were found to be associated with the disease. Here, F. mangiferae from mango cv Dashehri was morphologically characterized. Typically, oval-shaped microconidia without septum and crescent-shaped macroconidia with 3-septate were more often observed, whereas not a single chlamydospore was detected. The length and width of micro- and macro-conidia were 7.5, 55, 3.2, and 3.5, respectively. The plant growth regulators such as NAA, GA3, BAP and ethrel were found to induce in vitro germination of conidia of F. mangiferae after 12 h. In contrast, antimalformin silver nitrate (AgNO3) inhibits conidial germination in vitro and none of conidia was germinated beyond 500 ppm, however antimalformin glutathione was highly effective in stimulating conidial germination of F. mangiferae in vitro at > 1000 ppm after 24 h. We observed that the response of F. mangiferae to germinate the conidia in vitro under influence of plant growth regulators and antimalformins is not coincided with earlier findings of reduced disease incidence by exogenous application of these compounds. The present findings do not authenticate the involvement of F. mangiferae in the disease, however hormonal imbalance, most probably ethylene, might be responsible for deformed functional morphology of panicle. Further, a signal transduction mechanism of stress-stimulated ethylene imbalance causing physio-morphological changes in reproductive organs of mango flower and thereby failure of fertilization and fruit set, which needs to be investigated. PMID:24505497

Ansari, Mohammad Wahid; Tula, Suresh; Shukla, Alok; Pant, Ramesh Chandra; Tuteja, Narendra

2013-11-01

22

Effect of Fungal and Plant Metabolites on Broomrapes (Orobanche and Phelipanche spp.) Seed Germination and Radicle Growth.  

PubMed

Orobanche and Phelipanche species (the broomrapes) are root parasitic plants, some of which cause heavy yield losses on important crops. The development of herbicides based on natural metabolites from microbial and plant origin, targeting early stages on parasitic plant development, might contribute to the reduction of broomrape seed bank in agricultural soils. Therefore, the effect of metabolites belonging to different classes of natural compounds on broomrape seed germination and radicle development was assayed in vitro. Among the metabolites tested, epi-sphaeropsidone, cyclopaldic acid, and those belonging to the sesquiterpene class induced broomrape germination in a species-specific manner. epi-Epoformin, sphaeropsidin A, and cytochalasans inhibited germination of GR24-treated broomrape seeds. The growth of broomrape radicle was strongly inhibited by sphaeropsidin A and compounds belonging to cyclohexene epoxide and cytochalasan classes. Broomrape radicles treated with epi-sphaeropsidone developed a layer of papillae while radicles treated with cytochalasans or with sphaeropsidin A turned necrotic. These findings allow new lead natural herbicides for the management of parasitic weeds to be identified. PMID:25272312

Cimmino, Alessio; Fernndez-Aparicio, Mnica; Andolfi, Anna; Basso, Sara; Rubiales, Diego; Evidente, Antonio

2014-10-29

23

Effect of nanosilica and silicon sources on plant growth promoting rhizobacteria, soil nutrients and maize seed germination.  

PubMed

The study was aimed at evaluating the effect of nanosilica and different sources of silicon on soil properties, total bacterial population and maize seed germination. Nanosilica was synthesised using rice husk and characterised. Silica powder was amorphous (50 nm) with >99.9% purity. Sodium silicate treated soil inhibited plant growth promoting rhizobacteria in contrast to nanosilica and other bulk sources. Surface property and effect of soil nutrient content of nanosilica treatment were improved. Colony forming unit (CFU) was doubled in the presence of nanosilica from 4 105 CFU (control) to 8 105 CFU per gram of soil. The silica and protein content of bacterial biomass clearly showed an increase in uptake of silica with an increase in nanosilica concentration. Nanosilica promoted seed germination percentage (100%) in maize than conventional Si sources. These studies show that nanosilica has favourable effect on beneficial bacterial population and nutrient value of soil. PMID:24028804

Karunakaran, Gopalu; Suriyaprabha, Rangaraj; Manivasakan, Palanisamy; Yuvakkumar, Rathinam; Rajendran, Venkatachalam; Prabu, Periyasamy; Kannan, Narayanasamy

2013-09-01

24

Effects of an industrial effluent on plant colonization and on the germination and post-germinative growth of seeds of terrestrial and aquatic plant species.  

PubMed

Major oil sands industrial companies are located in the Athabasca Oil Sands Deposit in northeastern Alberta, Canada. During the process used to extract light crude oil (via hot water digestion and flotation), gypsum is usually added to produce consolidated tails (CT) and CT release water. The vast volumes of process-treated waters (effluent) are held within large dyked tailings ponds. Toward testing viable options for reclamation, various hummock-wetlands systems have been constructed; in addition, natural wetlands (inhabited by obligate wetland plant species) have become established as a result of seeping of the effluents held within the large dyked ponds. Vegetation surveys conducted on and around the industrial site revealed that the constructed wetlands associated with the dyke drainage (effluent treated with phosphorous) and consolidated tails (CT; effluent treated with gypsum) had low biodiversity and were not invaded by many aquatic plants. Although the natural wetland was also not invaded by many aquatic species, it was found to be as diverse as the reference wetlands (i.e. off-site wetlands not exposed to the effluents). Exposure to oil sands effluents had an inhibitory effect on the germination (percent and/or rate) of several plant species (tomato, clover, wheat, rye, pea, reed canary grass, loblolly pine); clover and tomato seed germination were most affected. Two treatments in particular (effluents from the natural on-site wetland and the CT constructed wetland), delayed germination, and also led to reduced fresh weight of seedlings of tomato, wheat, clover and loblolly pine. The osmolarities of the effluents associated with the natural on-site wetland and CT constructed wetland were 712 and 728 mOs/kg, respectively; substituting these effluents with solutions of polyethylene glycol of the same osmotic potentials had a greater inhibitory effect on germination rate. The negative effects of the effluents on seed germination may account for the paucity of aquatic species that invaded the oil sands impacted wetlands. This factor will also be critical in determining the long-term feasibility of hummock-wetland systems. PMID:11843534

Crowe, A U; Plant, A L; Kermode, A R

2002-01-01

25

Incorporation of plant growth regulators into the priming solution improves sugar beet germination, emergence and seedling growth at low-temperature.  

PubMed

In a series of experiments, impact of inclusion of plant growth regulators into the KNO3 priming solution on low temperature seed germination, emergence percentage and seedling growth of sugar beet was investigated. Seeds were primed in 3% KNO3 solution for 6 days at 25 degrees C in darkness containing one of the following: 0, 0.05, 0.1, 0.5, or 1 mM acetyl salicylic acid (ASA) or 1, 3, 5 or 10 microM methyl jasmonated (MeJA). A non-primed treatment was also included in the experiment. Priming seeds in the presence or absence of plant growth regulators in general improved final germination percentage (FGP), germination rate (G50) and germination synchrony (G10-90) at 15 degrees C compared with non-primed seeds which had an FGP of 42%, G50 of 11.3 days and G10-90 of 11.7 days. Priming seeds in KNO3 solution containing 0.05 mM of ASA resulted in the highest germination percentage (89%), fastest germination rate (G50 = 5.3 days) and the most synchronous germination (G10-90 = 10.7 days). Emergence percentages were the highest for the seeds primed in the presence of 0.05 mM ASA (83%) and 3 microM MeJA (81%) while non-primed seeds had an emergence percentage of 40%. Fastest emergence rate (E50) were also obtained from seeds primed in KNO3 supplemented with 3 microM MeJA (E50 = 14.4 days) and 0.05 mM ASA (E50 = 14.4 days). Shoot fresh and dry weight of seedlings were significantly affected by treatments and priming in the presence of 0.05 mM ASA resulted in highest seedling shoot fresh and dry weight. These results indicate that priming seeds in 0.05 mM of ASA or 3 microM MeJA incorporated into the KNO3 solution can be more effective than KNO3 alone to improve low temperature germination performance of seeds and subsequent seedling growth. PMID:19090156

Govahi, Mostafa; Arvin, Mohammad Javad; Saffari, Ghazaleh

2007-10-01

26

Comparative effects of some plant growth regulators on the germination of barley and radish seeds under high temperature stress  

Microsoft Academic Search

The effects of gibberellic acid, kinetin, benzyladenine, ethylene, 24-epibrassinolide, tri- acontanol and polyamines (cadaverine, putrescine, spermidine, spermine), alone or in combinations, on germination and early seedling growth under high temperature conditions of barley and radish seeds were studied. High temperature both delayed and inhibited the germinations of both the species. Only three of the single applications gibberellic acid, kinetin and

Kursat Cavusoglu; Kudret Kabar

2007-01-01

27

Enhancing Effect of Shimizuomyces paradoxus on Seed Germination and Seedling Growth of Canola, Plant Growth of Cucumber, and Harvest of Tomato.  

PubMed

Shimizuomyces paradoxus showed no inhibitory effect against plant pathogen fungi, such as Fusarium oxysporum f. sp. lycopersici and Alternaria solani. The S. paradoxus culture filtrate showed higher seed germination and seedling growth rates in canola than distilled water and potato-dextrose broth. A conidial suspension of 1.010(4)/mL resulted in the highest growth stimulating effects on total plant length, and fresh and dry weight of shoots and roots in cucumber, when compared to the highest suspension concentration. Total plant length and shoot weight increased with the foliar spray treatment, and root length and root weight increased by simultaneous treatments of soil drenching and foliar spray in cucumber. Lower concentrations of the S. paradoxus conidial suspension increased the harvest of tomato fruit. PMID:22783066

Sung, Gi-Ho; Shrestha, Bhushan; Park, Ki-Byung; Han, Sang-Kuk; Sung, Jae-Mo

2011-03-01

28

Allelopathic effect of Nepetameyeri Benth. extracts on seed germination and seedling growth of some crop plants  

Microsoft Academic Search

In order to evaluate the allelopathic potential of Nepeta meyeri Benth., the effects of aqueous extracts (0.125, 0.25, 0.5, 1, 2.5 and 5%) prepared from roots and leaves of N. meyeri were studied on the seed germination and seedling growth of several economically important crops (barley, wheat, canola,\\u000a safflower, and sunflower). Both the root and leaf extracts of N. meyeri

Salih Mutlu; kke? Atici

2009-01-01

29

Effect of vermicast generated from an allelopathic weed lantana (Lantana camara) on seed germination, plant growth, and yield of cluster bean (Cyamopsis tetragonoloba).  

PubMed

In perhaps the first-ever study of its kind, the effect of vermicompost, derived solely from an allelopathic weed, on the germination, growth, and yield of a botanical species, has been carried out. In test plots, the soil was treated with the vermicompost of lantana (Lantana camara) at the rates of 5, 7.5, and 10tha(-1), and cluster bean (Cyamopsis tetragonoloba) was grown on it. The performance of these systems was compared with the systems in which the soil was fortified with inorganic fertilizers (IFs) in concentrations equivalent to those present in the respective vermicompost (VC) treatments. Additionally, a set of control was studied in which the soil was used without fortification by either VC or IF. It was seen that up to 51.5% greater germination success occurred in the VC treatments compared to controls. VC also supported better plant growth in terms of stem diameter, shoot length, shoot mass, number of leaves, and leaf pigments. The positive impact extended up to fruit yield. In addition, vermicast application enhanced root nodule formation, reduced disease incidence, and allowed for a smaller number of stunted plants. The results indicate that allelopathic ingredients of lantana seem to have been totally eliminated during the course of its vermicomposting and that lantana vermicompost has the potential to support germination, growth, and fruit yield better than equivalent quantities of IFs. PMID:24946699

Karthikeyan, M; Hussain, N; Gajalakshmi, S; Abbasi, S A

2014-11-01

30

Germination and growth of wheat in simulated Martian atmospheres  

NASA Astrophysics Data System (ADS)

One design for a manned Mars base incorporates a bioregenerative life support system based upon growing higher plants at a low atmospheric pressure in a greenhouse on the Martian surface. To determine the concept's feasibility, the germination and initial growth of wheat ( Triticum aestivum) was evaluated at low atmospheric pressures in simulated Martian atmosphere (SMA) and in SMA supplemented with oxygen. Total atmospheric pressures ranged from 10 to 1013 mb. No seeds germinated in pure SMA, regardless of atmospheric pressure. In SMA plus oxygen at 60 mb total pressure, germination and growth occurred but were lower than in the Earth atmosphere controls.

Schwartzkopf, Steven H.; Mancinelli, Rocco L.

31

Salt index of potassium phosphate fertilizers and its relation to germination and early plant growth of field crops  

E-print Network

, KCl* and MAPs 65 17 Analysis of phosphorus (P) and potassium (K) from corn plant material used in root growth study. Los? salt and high salt fertilizers were spot placed 7 cm below the surface between 2 corn plants at the rate of 100 mg P. Each..., KCl* and MAPs 65 17 Analysis of phosphorus (P) and potassium (K) from corn plant material used in root growth study. Los? salt and high salt fertilizers were spot placed 7 cm below the surface between 2 corn plants at the rate of 100 mg P. Each...

Freeouf, Jerry Allen

2012-06-07

32

The effect of plant growth-promoting rhizobacteria on asparagus seedlings and germinating seeds subjected to water stress under greenhouse conditions.  

PubMed

Plant growth-promoting rhizobacteria (PGPR) can have positive effects on vigour and productivity, especially under stress conditions. In asparagus (Asparagus officinalis L.) field culture, seeds are planted in high-density nurseries, and 1-year-old crowns are transplanted to production fields. Performance can be negatively affected by water stress, transplant shock, and disease pressure on wounded roots. PGPR inoculation has the potential to alleviate some of the stresses incurred in the production system. In this study, the effects of PGPR (Pseudomonas spp.) treatment were determined on 3-week-old greenhouse-grown seedlings and germinating seeds of 2 asparagus cultivars. The pots were irrigated to a predetermined level that resulted in optimum growth or the plants were subjected to drought or flooding stress for 8 weeks. The cultivars responded differently to PGPR: single inoculations of seedlings enhanced growth of 'Guelph Millennium' under optimum conditions and 'Jersey Giant' seedlings under drought stress. Seed inoculations with PGPR resulted in a positive response only for 'Guelph Millennium', for which both single or multiple inoculations enhanced plant growth under drought stress. PMID:19396238

Liddycoat, Scott M; Greenberg, Bruce M; Wolyn, David J

2009-04-01

33

Comparison of the seed germination effects of synthetic analogs of strigol, gibberellic acid, cytokinins, and other plant growth regulators  

Microsoft Academic Search

Four synthetic multiring analogs of strigol, a naturally occurring sesquiterpene lactone that promotes germination of dormant seeds ofStriga (witchweed), were found to stimulate germination of dormantLactuca (lettuce) seeds. The effects on light-sensitive and light-insensitive lettuce seeds were concentration-dependent and exceeded those produced by equimolar (0.1 mM) solutions of gibberellic acid. Strigol and epistrigol promoted lettuce seed germination to a lesser

Judith M. Bradow; William J. Connick; Armand B. Pepperman

1988-01-01

34

Seed germination and growth inhibitory cadinenes from Eupatorium adenophorum spreng  

Microsoft Academic Search

Chloroform extract of the aerial parts ofEupatorium adenophorum Spreng was fractionated and examined for growth inhibition. Bioassay-directed fractions of the plant materials afforded three known cadinenes and ?-sitosterol. The effects of different fractions as well as isolated cadinenes were determined usingAllium cepa, Raphanus sativus, andCucumis sativus seeds. Three-day exposure to these cadinenes significantly inhibited germination and seedling growth of all

Narayan C. Baruah; Jadab C. Sarma; Soneswar Sarma; Ram P. Sharma

1994-01-01

35

Response of Pollen Germination and Tube Growth to Cadmium with Special Reference to Low Concentration Exposure  

Microsoft Academic Search

Cadmium is one of the most important heavy metal pollutants highly hazardous to plants. Pollen is considered to be more sensitive to pollutants than are vegetative parts of the plants. Five herb species were tested for responses in pollen germination and tube growth to Cd exposure in vitro. Pollen germination of all the species was inhibited at Cd concentrations of

Zhi-Ting Xiong; Yong-Hua Peng

2001-01-01

36

Interaction of jasmonic acid with some plant growth regulators in the control of apple (Malus domestica) embryo germination  

Microsoft Academic Search

Embryos isolated from dormant apple seeds were treated with jasmonic acid (JA), gibberellin A3 (GA3), abscisic acid (ABA) and hydrogen cyanide in darkness and in light. The chemicals were present in the culture medium continuously and simultaneously or applied for 2 days and in different sequences. All treatments stimulated embryo germination except ABA, which was strongly inhibitory. Additive effects of

Rajiv Ranjan; Stanislaw Lewak

1994-01-01

37

Modeling the effects of cymene on the distribution of germination and growth of Beauveria bassiana  

E-print Network

Essential oils have antifungal and antipathogenic effects and therefore are targets in plant pathology research for their potential uses as natural substitutes for inorganic plant pesticides. Beauveria bassiana, an entomopathogenic fungus, can endophytically colonize a vast number of plant species and trigger induced systemic resistance against plant pathogens. Spore germination is the most vulnerable in the fungal life cycle and is therefore a good candidate for monitoring the effect of essential oils on the growth of B. bassiana. Percentage germination of fungal spores and length of germination tubes were recorded from experiments. A mathematical model that was able to capture the effects of cymene, an essential oil produced by Monarda, on the germination and growth was developed. This is the first report of a model for the impact of essential oils on B. bassiana spore germination.

Luong Nguyen; Dubravka Bodiroga; Reka Kelemen; Jaewook Joo; Kimberly D. Gwinn

2010-10-05

38

Pollen germination and tube growth in rye (Secade cereale L.) homozygous and heterozygous for reciprocal translocations.  

PubMed

To contribute to the knowledge of the role of reciprocal translocations in rye, a component of fertility was estimated by comparing germination and pollen tube growth in homozygous and heterozygous plants for reciprocal translocations. The results obtained indicate that there are no differences in germination and pollen tube growth rate when homozygous and heterozygous plants as a whole are compared. However, there are significant differences in pollen tube growth between plants carrying different translocations. This suggests that the chromosome constitution of a plant is relevant to these fitness-estimating parameters together with its particular genetic background. PMID:24254028

Figueiras, A M; Candela, M; Lacadena, J R

1985-03-01

39

Effect of Burning on Germination of Tallgrass Prairie Plant Species  

Microsoft Academic Search

Seeds from 10 prairie plant species of burned and unburned portions of three tallgrass prairies were collected and tested for germinability. Germination of big bluestem (Andropogon gerardii Vitman) consistently averaged higher with burning. Indiangrass (Sorghastrum nutans L.) and sideoats grama [Bouteloua curtipendula (Michx.) Torr.] averaged 5% higher with burning on two of the three sites, although for indiangrass average germination

Sherry R. Rohn; Thomas B. Bragg

1989-01-01

40

Efficient production of human acidic fibroblast growth factor in pea ( Pisum sativum L.) plants by agroinfection of germinated seeds  

Microsoft Academic Search

BackgroundFor efficient and large scale production of recombinant proteins in plants transient expression by agroinfection has a number\\u000a of advantages over stable transformation. Simple manipulation, rapid analysis and high expression efficiency are possible.\\u000a In pea, Pisum sativum, a Virus Induced Gene Silencing System using the pea early browning virus has been converted into an\\u000a efficient agroinfection system by converting the

Yajun Fan; Wei Li; Junjie Wang; Jingying Liu; Meiying Yang; Duo Xu; Xiaojuan Zhu; Xingzhi Wang

2011-01-01

41

ABI5 acts downstream of ABI3 to execute an ABA-dependent growth arrest during germination  

E-print Network

osmotic tolerance in germinated embryos whose growth is arrested. ABI5 expression is greatly reduced to establish seedling growth represents a fragile phase in the life cycle of a plant. During this developmental

Chait, Brian T.

42

Insecticides and Arable Weeds: Effects on Germination and Seedling Growth  

Microsoft Academic Search

The decline of many arable weed species in Northern Europe has been attributed to the intensification of modern agriculture and in particular, increasing pesticide use. In this study, we examined the effect of two insecticides, dimethoate and deltamethrin, on the germination and seedling growth of six arable weed species. Although germination was unaffected by insecticide application, seedling growth of four

M. E. Hanley; M. D. Whiting

2005-01-01

43

Response of pollen germination and tube growth to cadmium with special reference to low concentration exposure.  

PubMed

Cadmium is one of the most important heavy metal pollutants highly hazardous to plants. Pollen is considered to be more sensitive to pollutants than are vegetative parts of the plants. Five herb species were tested for responses in pollen germination and tube growth to Cd exposure in vitro. Pollen germination of all the species was inhibited at Cd concentrations of 2.51 microg/mL and higher, and tube growth was inhibited at concentrations of 1.58 microg/ml and higher. Cadmium, at low concentrations, stimulated pollen tube growth. The pollen response to Cd stress exhibited interspecies differences. Vicia angustifolia and V. tetrasperma were sensitive to Cd, and were inhibited in either pollen germination or tube growth by Cd at 0.01 microg/mL. Plantago depressa was less sensitive; pollen germination and tube growth were not inhibited until the Cd concentration reached 2.51 and 1.58 microg/mL, respectively, and its tube growth displayed two stimulatory peaks; the one that appeared at 1.00 microg/mL showed the highest tube length in all species tested. These results suggest that Cd, even at low concentrations, may adversely affect plant reproduction by inhibiting pollen germination and tube growth. PMID:11161677

Xiong, Z T; Peng, Y H

2001-01-01

44

Insecticides and arable weeds: effects on germination and seedling growth.  

PubMed

The decline of many arable weed species in Northern Europe has been attributed to the intensification of modern agriculture and in particular, increasing pesticide use. In this study, we examined the effect of two insecticides, dimethoate and deltamethrin, on the germination and seedling growth of six arable weed species. Although germination was unaffected by insecticide application, seedling growth of four species was decreased by exposure to deltamethrin (Capsella bursa-pastoris and Poa annua), dimethoate (Agrostemma githago), or by both insecticides together (Urtica urens). While increased herbicide use, seed cleaning, and changing sowing times may be of primary importance in explaining the reduction of northern Europe's arable weed flora, our results indicate that insecticide use may also be a contributory factor. Moreover, those species that exhibit apparent tolerance of the insecticides tested, particularly the grass Avena fatua, may benefit from continued insecticide use. The ability to tolerate these agrochemicals, in tandem with reduced herbivory and competition from plants, whose growth is reduced by insecticide application, is likely to confer a significant competitive advantage on insecticide-resistant weed species. PMID:16385742

Hanley, M E; Whiting, M D

2005-05-01

45

Seed germination and salinity tolerance in plant species growing on saline wastelands  

Microsoft Academic Search

Seven plant species including three chenopods:Suaeda fruticosa, Kochia indica, Atriplex crassifolia and four grasses:Sporobolus arabicus, Cynodon dactylon, Polypogon monspeliensis, Desmostachya bipinnata, varied greatly in their seed germination and growth responses to soil moisture or salinity. The germination percentage of\\u000a each species was significantly lower at soil moisture level of 25 % of water holding capacity than at the levels ranging

K. Mahmood; K. A. Malik; M. A. K. Lodhi; K. H. Sheikh

1996-01-01

46

Strigolactones as Germination Stimulants for Root Parasitic Plants  

PubMed Central

Witchweeds (Striga spp.) and broomrapes (Orobanche and Phelipanche spp.) are the two most devastating root parasitic plants belonging to the family Orobanchaceae and are causing enormous crop losses throughout the world. Seeds of these root parasites will not germinate unless they are exposed to chemical stimuli, germination stimulants produced by and released from plant roots. Most of the germination stimulants identified so far are strigolactones (SLs), which also function as host recognition signals for arbuscular mycorrhizal fungi and a novel class of plant hormones inhibiting shoot branching. In this review, we focus on SLs as germination stimulants for root parasitic plants. In addition, we discuss how quantitative and qualitative differences in SL exudation among sorghum cultivars influence their susceptibility to Striga. PMID:20403809

Yoneyama, Koichi; Awad, Ayman A.; Xie, Xiaonan; Yoneyama, Kaori; Takeuchi, Yasutomo

2010-01-01

47

Effect of salinity on seed germination, seedling growth, and physiological characteristics of Perilla frutescens  

Microsoft Academic Search

Salt stress is one of the major environmental factors limiting crop growth and yield. To understand the effect of salt stress on plant growth, we investigated the response of three perilla varieties (Suyin 1, Ziye 7, and Ziye 10) to NaC1 exposure at concentrations of 0, 50, 100, 150, 200, and 250mM in terms of seed germination, seedling growth, root

Zhijun Zhang; Huizhen Li; Shaojun Qiao; Xin Zhang; Peipei Liu; Xiliang Liu

2011-01-01

48

Effect of salinity on seed germination, seedling growth, and physiological characteristics of Perilla frutescens  

Microsoft Academic Search

Salt stress is one of the major environmental factors limiting crop growth and yield. To understand the effect of salt stress on plant growth, we investigated the response of three perilla varieties (Suyin 1, Ziye 7, and Ziye 10) to NaC1 exposure at concentrations of 0, 50, 100, 150, 200, and 250mM in terms of seed germination, seedling growth, root

Zhijun Zhang; Huizhen Li; Shaojun Qiao; Xin Zhang; Peipei Liu; Xiliang Liu

2012-01-01

49

Plant pathology Growth enhancement of maize (Zea mays L)  

E-print Network

plant varieties using the criterion of plant-growth promotion appeared to be a very useful tool. Zea mays / Azospirillum lipoferum / germination tests / plant genotype / plant-growth promotion Résumé / génotype de la plante hôte / promotion de crois- sance végétale INTRODUCTION Rhizospheric bacteria

Paris-Sud XI, Université de

50

Proteomics Identification of Differentially Expressed Proteins Associated with Pollen Germination and Tube Growth Reveals Characteristics of Germinated Oryza sativa Pollen  

Microsoft Academic Search

Mature pollen from most plant species is metabolically quiescent; however, after pollination, it germinates quickly and gives rise to a pollen tube to transport sperms into the embryo sac. Because methods for collecting a large amount of in vitro germinated pollen grains for tran- scriptomics and proteomics studies from model plants of Arabidopsis and rice are not available, molecular informa-

Shaojun Dai; Taotao Chen; Kang Chong; Yongbiao Xue; Siqi Liu; Tai Wang

2006-01-01

51

Germination requirements of New Zealand native plants: a review  

Microsoft Academic Search

A review of our knowledge of the germination requirements of seeds of indigenous New Zealand plants is presented. A search of the literature reveals information, in varying detail, on only 113 species, some 5% of the estimated total of vascular plants, most of them from forest habitats. The New Zealand flora, much of it now endangered, represents a unique genetic

D. W. Fountain; H. A. Outred

1991-01-01

52

Acceleration of germination and early growth of wheat and bean seedlings grown under various magnetic field and osmotic conditions.  

PubMed

Magnetic field (MF) can have different effects on plant metabolism depending on its application style, intensity, and environmental conditions. This study reports the effects of different intensities of static MF (4 or 7 mT) on seed germination and seedling growth of bean or wheat seeds in different media having 0, 2, 6, and 10 atmosphere (atm) osmotic pressure prepared with sucrose or salt. The germination percentages of the treated seeds were compared with untreated seeds germinated in different osmotic pressure during 7 days of incubation. The application of both MFs promoted the germination ratios of bean and wheat seeds, regardless of increasing osmotic pressure of sucrose or salt. Growth data measured on the 7th day showed that the treated plants grew faster than control. After 7 days of incubation, the mean length of treated seedlings was statistically higher than control plants in all the media. The greatest germination and growth rates in both plants were from the test groups exposed to 7 mT MF. Strikingly, effects of static MF on germination and growth increased positively with increasing osmotic pressure or salt stress compared to their respective controls. On the other hand, MF application caused an increase in dry biomass accumulation of root and shoots of both seedlings; however, this effect was found statistically important in all the conditions for wheat but not for bean, in general. PMID:19681058

Cakmak, Turgay; Dumlupinar, Rahmi; Erdal, Serkan

2010-02-01

53

Nitrogen effects on seed germination and seedling growth  

Microsoft Academic Search

Recent evidence associates the persistence of invasive plant species with disturbance and fluctuations in distinct forms of mineral N in soils. We conducted soil and hydroponic experi- ments to investigate the influence of N form and availability on germination and seedling development of 2 invasive annual grasses, cheatgrass (Bromus tectorum) and medusahead (Taeniatherum caput-medusae) and 6 perennial grasses, blue- bunch

THOMAS A. MONACO; CHARLES T. MACKOWN; DOUGLAS A. JOHNSON; THOMAS A. JONES; JEANETTE M. NORTON; JAY B. NORTON; MARGARET G. REDINBAUGH

2003-01-01

54

WHAT IS PLANT TISSUE CULTURE? Plant tissue culture involves the growth of plant cells, tissues or segments for purposes such as  

E-print Network

, or even naturally, such as the "babies" or propagules sent off by spider plants. Plant tissue culture uses improve germination or overcome any germination blockers. PROTOPLAST CULTURE AND USES: When a plant cell1 WHAT IS PLANT TISSUE CULTURE? Plant tissue culture involves the growth of plant cells, tissues

Durako, Michael J.

55

Plant Growth Regulation  

NSDL National Science Digital Library

Plant growth regulators, including auxin, gibberellin, cytokinin, abscisic acid, and ethylene, are investigated in this learning activity to demonstrate how these chemicals (hormones) affect plant growth and development.

This page authored by Jim Bidlack, University of Central Oklahoma, based on original activities by Long Ashton Research Station, KScience, Cynthia Herbrandson, Kellogg Community College, Ross Koning, Eastern Connecticut State University, and A.G. Scientific, Inc.

56

Cardinal temperatures for germination and early growth of two Lesquerella species  

Microsoft Academic Search

Lesquerella (Lesquerella fendleri) is a potential alternative crop that is being studied for commercial oilseed production. Understanding the minimum temperatures for germination and seedling growth is important for determining potential areas for lesquerella production. The objectives of this study were to determine the cardinal temperatures for germination and seedling growth, and to screen ecotypes for germination and growth characteristics. A

N. R. Adam; D. A. Dierig; T. A. Coffelt; M. J. Wintermeyer; B. E. Mackey; G. W. Wall

2007-01-01

57

Mapping Salinity Tolerance during Arabidopsis thaliana Germination and Seedling Growth  

PubMed Central

To characterize and dissect genetic variation for salinity tolerance, we assessed variation in salinity tolerance during germination and seedling growth for a worldwide sample of Arabidopsis thaliana accessions. By combining QTL mapping, association mapping and expression data, we identified genomic regions involved in salinity response. Among the worldwide sample, we found germination ability within a moderately saline environment (150 mM NaCl) varied considerable, from >90% among the most tolerant lines to complete inability to germinate among the most susceptible. Our results also demonstrated wide variation in salinity tolerance within A. thaliana RIL populations and identified multiple genomic regions that contribute to this variation. These regions contain known candidate genes, but at least four of the regions contain loci not yet associated with salinity tolerance response phenotypes. Our observations suggest A. thaliana natural variation may be an underutilized resource for investigating salinity stress response. PMID:21857956

DeRose-Wilson, Leah; Gaut, Brandon S.

2011-01-01

58

Genetic variation in germination, growth, and survivorship of red maple in response to subambient through elevated atmospheric CO2  

Microsoft Academic Search

Genetic variation in plant response to atmospheric carbon dioxide (CO2) may have influenced paleo-vegetation dynamics and could determine how future elevated CO2 drives plant evolution and ecosystem productivity. We established how levels of relatedness - the maternal family, population, and provenance - affect variation in the CO2 response of a species. This 2-year growth chamber experiment focused on the germination,

JACQUELINE E. M OHAN; J AMES S. C LARK

59

Intersection of two signalling pathways: extracellular nucleotides regulate pollen germination and pollen tube growth via nitric oxide  

Microsoft Academic Search

Plant and animal cells release or secrete ATP by various mechanisms, and this activity allows extracellular ATP to serve as a signalling molecule. Recent reports suggest that extracellular ATP induces plant responses ranging from increased cytosolic calcium to changes in auxin transport, xenobiotic resistance, pollen germination, and growth. Although calcium has been identified as a secondary messenger for the extracellular

Stuart A. Reichler; Jonathan Torres; Amy L. Rivera; Viviana A. Cintolesi; Greg Clark; Stanley J. Roux

2009-01-01

60

Germination, growth, osmotic adjustment and ionic balance of wheat in response to saline and alkaline stresses  

Microsoft Academic Search

The effects of saline and alkaline stresses (from 1:1 molar ratios of NaCl?:?Na2SO4 and NaHCO3?:?Na2CO3, respectively) were compared on the germination, growth, osmotic adjustment and ionic balance of wheat seedlings to elucidate the mechanism of alkaline stress (high pH) damage to plants and their physiological adaptive mechanism to alkaline stress. The effects of salines on the activity and free concentrations

Rui Guo; Lianxuan Shi; Yunfei Yang

2009-01-01

61

Germination and Early Seedling Growth of Chaffy-Seeded Grasses at Negative Water Potentials  

Microsoft Academic Search

chaffy-seeded grasses can be debearded, i.e., removal ofthehairsandawn(Ahringet al.,1964)orprocessedto Drought is the most frequent cause of stand establishment failure remove all appendages leaving only caryopses (Beisel, of native grasses. An experiment was conducted to determine the interactions of seed processing and simulated dry conditions on seed 1985). When conditions are favorable, planting caryop- germination and seedling growth of five chaffy-seeded,

T. L. Springer

2005-01-01

62

[Impact of priming on seed germination and seedling growth of Oldenlandia diffusa under drought stress].  

PubMed

Current study was carried out to optimize the priming condition of Oldenlandia diffusa seeds, and improve germination rate and seed vigor of 0. diffusa seeds under drought conditions. Uniform design was used to optimize the concentration and priming time of three priming materials (PEG, KNO3, GA3). Different concentrations of polyethylene glycol (PEG) was used to simulate drought stress. The seedling was cultured in 1/4 Hoagland medium for 30 d. The results showed that seed priming treatment with 366 mg x kg(-1) GA3 for 1h resulted in significant increase in germination rate, germination index, vigor, root length, plant height and biomass of O. diffusa seeds under drought stress (15% PEG), while seed priming with 3.0% KNO3 for 1 h showed little effect on germination and growth of O. diffusa seeds under drought stress. Seed priming treatment with appropriate GA3 concentration and priming time could enhance seed germination and drought resistance of O. diffusa in seedling stage. PMID:25039170

Zhu, Zai-Biao; Lu, Wei-Wei; Guo, Qiao-Sheng; Cao, Ya-Yue; Feng, Shan; Ning, Zi-Jun

2014-04-01

63

Coordinated action of ?-galactosidases in the cell wall of embryonic axes during chickpea germination and seedling growth.  

PubMed

The plant cell wall is a dynamic structure whose constant modification is necessary for plant cells to grow and divide. In the cell walls of chickpea (Cicer arietinum) there are at least four ?-galactosidases, whose presence and location in embryonic axes during the first 48 h of seed imbibition are discussed in this paper. We examined their roles as cell wall-modifying enzymes in germinative and/or post-germinative events. At the start of germination, only ?V-Gal, and to a lesser extent ?IV-Gal, appear in the axes before rupture of the testa, suggesting they are related to germination sensu stricto. Once the testa has broken, the four ?-galactosidases are involved in growth and differentiation of the axes. Immunolocation of the different proteins in axes, which in part confirms previous results in seedlings and plants, allows assignment of post-germinative roles to ?I-Gal and ?III-Gal as cell wall modifiers in vascular tissue elements. ?IV-Gal and ?V-Gal participate in the initial events of germination in which cell walls are involved: ?V-Gal in cell proliferation, detachment of root cap cells and initial vascular tissue differentiation; both of them in xylem maturation; and ?IV-Gal in thickening of the primary cell wall. Together with other cell wall-modifying enzymes, such as expansins and XTH, chickpea galactosidases might function in a sequential order in turnover of the primary cell wall, allowing the elongation of embryonic axes during seed germination. PMID:23731125

Hernndez-Nistal, J; Martn, I; Dopico, B; Labrador, E

2014-03-01

64

Effects of Three Fire-Suppressant Foams on the Germination and Physiological Responses of Plants  

NASA Astrophysics Data System (ADS)

Suppressant foams used to fight forest fires may leave residual effects on surviving biota that managers need to consider prior to using them. We examined how three fire-suppressant foams (FSFs) (Forexpan S, Phos-Chek-WD881, and Silv-ex) affected seed germination and physiological responses of three plant species. Exposure to FSFs, whether in diluted concentrations or those typical in the field, reduced final germination percentages of seeds grown in petri dishes and within growth chambers. However, the FSFs did not cause total germination failure in any treatment. Inhibition of germination increased with longer exposure times, but only to diluted FSF solutions. Unlike in the laboratory experiments, none of the three FSFs affected seedling emergence when tested in field conditions. Further, we found no evidence of long-term phytotoxic effects on antioxidant enzyme activity nor chlorophyll content of the plant saplings. Therefore, although the three FSFs showed evidence of phytotoxicity to plants in laboratory tests, their actual impact on terrestrial ecosystems may be minimal. We suggest that the benefits of using these FSFs to protect plants in threatened forest ecosystems outweigh their minor risks.

Song, Uhram; Mun, Saeromi; Waldman, Bruce; Lee, Eun Ju

2014-10-01

65

Effects of three fire-suppressant foams on the germination and physiological responses of plants.  

PubMed

Suppressant foams used to fight forest fires may leave residual effects on surviving biota that managers need to consider prior to using them. We examined how three fire-suppressant foams (FSFs) (Forexpan S, Phos-Chek-WD881, and Silv-ex) affected seed germination and physiological responses of three plant species. Exposure to FSFs, whether in diluted concentrations or those typical in the field, reduced final germination percentages of seeds grown in petri dishes and within growth chambers. However, the FSFs did not cause total germination failure in any treatment. Inhibition of germination increased with longer exposure times, but only to diluted FSF solutions. Unlike in the laboratory experiments, none of the three FSFs affected seedling emergence when tested in field conditions. Further, we found no evidence of long-term phytotoxic effects on antioxidant enzyme activity nor chlorophyll content of the plant saplings. Therefore, although the three FSFs showed evidence of phytotoxicity to plants in laboratory tests, their actual impact on terrestrial ecosystems may be minimal. We suggest that the benefits of using these FSFs to protect plants in threatened forest ecosystems outweigh their minor risks. PMID:24943813

Song, Uhram; Mun, Saeromi; Waldman, Bruce; Lee, Eun Ju

2014-10-01

66

Rice germination and seedling growth in the absence of oxygen  

PubMed Central

Background Higher plants are aerobic organisms which suffer from the oxygen deficiency imposed by partial or total submergence. However, some plant species have developed strategies to avoid or withstand severe oxygen shortage and, in some cases, the complete absence of oxygen (tissue anoxia) for considerable periods of time. Scope Rice (Oryza sativa) is one of the few plant species that can tolerate prolonged soil flooding or complete submergence thanks to an array of adaptive mechanisms. These include an ability to elongate submerged shoot organs at faster than normal rates and to develop aerenchyma, allowing the efficient internal transport of oxygen from the re-emerged elongated shoot to submerged parts. However, rice seeds are able to germinate anaerobically by means of coleoptile elongation. This cannot be explained in terms of oxygen transport through an emerged shoot. This review provides an overview of anoxic rice germination that is mediated through coleoptile rather than root emergence. Conclusions Although there is still much to learn about the biochemical and molecular basis of anaerobic rice germination, the ability of rice to maintain an active fermentative metabolism (i.e. by fuelling the glycolytic pathway with readily fermentable carbohydrates) is certainly crucial. The results obtained through microarray-based transcript profiling confirm most of the previous evidence based on single-gene studies and biochemical analysis, and highlight new aspects of the molecular response of the rice coleoptile to anoxia. PMID:18660495

Magneschi, Leonardo; Perata, Pierdomenico

2009-01-01

67

Influence of commercial fungicides on the germination, growth and virulence of four species of entomopathogenic fungi  

Microsoft Academic Search

The influence of 15 commercially available fungicides on the germination, growth and virulence of Metarhizium anisopliae, Beauveria bassiana, Isaria fumosorosea, and Lecanillium longisporum was evaluated. The influence of the fungicides on conidial germination was dependant on the fungicide type and dose. Most fungicides retarded conidial germination of all the fungi tested at 10 and at the recommended rate of application,

F. A. Shah; M. A. Ansari; J. Watkins; Z. Phelps; J. Cross; T. M. Butt

2009-01-01

68

The influence of microbial associations on germination of wheat seeds and growth of seedlings under impact of zinc salts  

Microsoft Academic Search

The life support systems (LSS) for long-term missions are to use cycling-recycling systems, including biological recycling. Higher plants are the traditional regenerator of air and producer of food. They should be used in many successive generations of their reproduction in LSS. Studies of influence of microbial associations on germination of wheat seeds and on growth of seedlings under impact of

L. A. Somova; N. S. Pechurkin

2009-01-01

69

The influence of microbial associations on germination of wheat seeds and growth of seedlings under impact of zinc salts  

NASA Astrophysics Data System (ADS)

The life support systems (LSS) for long-term missions are to use cycling-recycling systems, including biological recycling. Higher plants are the traditional regenerator of air and producer of food. They should be used in many successive generations of their reproduction in LSS. Studies of influence of microbial associations on germination of wheat seeds and on growth of seedlings under impact of heavy metals are necessary because of migration of heavy metals in LSS. Microbial associations are able to stimulate growth of plants, to protect them from pathogenic organisms and from toxicity of heavy metal salts. The goal of this work was to investigate effect of microbial associations on the germination of wheat seeds and on the growth of seedlings under impact of different concentrations of ZnSO4. The results of investigations showed that:Zinc salt had an adverse effect on germination of wheat seeds, beginning with concentrations of 8 MPC (Maximum Permissible Concentration) and higher.Microbial associations (concentrations -104 to 107 cells/ml) were able to decrease (partly or completely) the adverse effect of ZnSO4 on germination of wheat seeds.Concentrations (104-107 cells/ml) of microbial associations were able to decrease partly the adverse effect of zinc salts (intervals: from 1 to 32 MP?) on the growth and development of wheat plantlets during heterotrophic phase.The root system of plants was more sensitive to the adverse effect of ZnSO4 than shoots of plants.

Somova, L. A.; Pechurkin, N. S.

2009-04-01

70

Are cactus growth forms related to germination responses to light? A test using Echinopsis species  

NASA Astrophysics Data System (ADS)

In this study, we investigated the effect of light regimen (white light vs. darkness) on the germination of 12 species of the Echinopsis genus (tribe Trichocereeae, Cactaceae). This genus presents a variety of growth forms and relatively small and uniform seed size. These traits allowed us to test, within the same linage and removing seed mass effect, the hypothesis that the germination response to light (indifferent to light or positive photoblastic) is related to growth form. Our results reject this hypothesis since no seeds germinated in darkness, so all of the species can be classified as being positively photoblastic. The proportion of seed germination with white light was significantly different among cactus growth forms. Columnar cacti (arborescent, creeping and short) showed a greater proportion of seed germination than barrel and globose cacti. The germination rate differed among growth forms and species. At constant temperatures, creeping columnar cacti presented a significantly higher germination rate than the other growth forms. With alternating temperatures, columnar cacti showed higher germination rates than the other growth forms. The low proportion of seeds that germinated for some species indicates that they show seed dormancy. Our results suggest that germination responses to light in the cactus family could be related to seed mass and phylogenetic constraints.

Ortega-Baes, Pablo; Aparicio-Gonzlez, Mnica; Galndez, Guadalupe; del Fueyo, Patricia; Shring, Silvia; Rojas-Archiga, Mariana

2010-05-01

71

Effect of amending materials on growth of radish plant in salinized soil  

Microsoft Academic Search

The critical Na levels in soil which restricted seed germination and growth of radish, and effect of the amending materials on reducing the salinity hazard were determined by performing petri dish and pot experiments. The plants were grown in amended salinized soil in a phytotron for 21 days. Excess accumulation of Na in cells suppressed seed germination and plant growth.

G. Shokohifard; K. Sakagami; R. Hamada; S. Matsumoto

1989-01-01

72

[Effects of simulated acid rain on seed germination and seedling growth of different type corn Zea mays].  

PubMed

Taking normal corn, waxy corn, pop corn, and sweet corn as test materials, this paper studied their seed germination and seedling growth under effects of simulated acid rain (pH 6.0, 5.0, 4.0, 3.0, 2.0, and 1.0). Simulated acid rain at pH 2.0-5.0 had no significant effects on the seed germination and seedling growth, but at pH 1.0, the germination rate of normal corn, waxy corn, pop corn, and sweet corn was 91.3%, 68.7%, 27.5%, and 11.7%, respectively. As compared with those at pH 6.0 (CK), the germination rate, germination index, vigor index, germination velocity, shoot height, root length, shoot and root dry mass, and the transformation rate of stored substances at pH 1.0 had significant decrease, and the average germination time extended apparently. At pH 1.0, the effects of acid rain were greater at seedling growth stage than at germination stage, and greater on underground part than on aboveground part. Due to the differences in gene type, normal corn and waxy corn had the strongest capability against acid rain, followed by pop corn, and sweet corn. It was suggested that corn could be categorized as an acid rain-tolerant crop, the injury threshold value of acid rain was likely between pH 1.0 and pH 2.0, and normal corn and waxy corn would be prioritized for planting in acid rain-stricken area. PMID:24066549

Zhang, Hai-Yan

2013-06-01

73

Effect of cadmium on pollen germination and tube growth in Lilium longiflorum and Nicotiana tabacum  

Microsoft Academic Search

Summary.Cadmium had a highly toxic effect on pollen germination and tube growth, which were greatly inhibited as metal concentrations\\u000a increased. Cadmium concentrations up to 10?2 M completely stopped pollen germination and pollen showed an increasing tendency to burst within 1 h. At low concentrations,\\u000a the metal caused a slight stimulation of pollen germination, growth rate and tube elongation at the

T. Sawidis

2008-01-01

74

Steroid Hormones Stimulate Germination and Tube Growth of in Vitro Matured Tobacco Pollen.  

PubMed Central

A study of the effects of different steroids on germination and tube growth of tobacco pollen (Nicotiana tabacum L. cv Petit Havana SR1) matured in vitro is presented. Application of the mammalian steroid sex hormones (testosterone, progesterone, and estradiol) resulted in a stimulation of pollen germination and tube elongation. The presence of both steroids and flavonols in the germination medium strongly enhanced the growth of tobacco male gametophytes. PMID:12228388

Ylstra, B.; Touraev, A.; Brinkmann, A. O.; Heberle-Bors, E.; Tunen, AJV.

1995-01-01

75

QTL analysis of seed germination and pre-emergence growth at extreme temperatures in Medicago truncatula  

PubMed Central

Enhancing the knowledge on the genetic basis of germination and heterotrophic growth at extreme temperatures is of major importance for improving crop establishment. A quantitative trait loci (QTL) analysis was carried out at sub- and supra-optimal temperatures at these early stages in the model Legume Medicago truncatula. On the basis of an ecophysiological model framework, two populations of recombinant inbred lines were chosen for the contrasting behaviours of parental lines: LR5 at sub-optimal temperatures (5 or 10C) and LR4 at a supra-optimal temperature (20C). Seed masses were measured in all lines. For LR5, germination rates and hypocotyl growth were measured by hand, whereas for LR4, imbibition and germination rates as well as early embryonic axis growth were measured using an automated image capture and analysis device. QTLs were found for all traits. The phenotyping framework we defined for measuring variables, distinguished stages and enabled identification of distinct QTLs for seed mass (chromosomes 1, 5, 7 and 8), imbibition (chromosome 4), germination (chromosomes 3, 5, 7 and 8) and heterotrophic growth (chromosomes 1, 2, 3 and 8). The three QTL identified for hypocotyl length at sub-optimal temperature explained the largest part of the phenotypic variation (60% together). One digenic interaction was found for hypocotyl width at sub-optimal temperature and the loci involved were linked to additive QTLs for hypocotyl elongation at low temperature. Together with working on a model plant, this approach facilitated the identification of genes specific to each stage that could provide reliable markers for assisting selection and improving crop establishment. With this aim in view, an initial set of putative candidate genes was identified in the light of the role of abscissic acid/gibberellin balance in regulating germination at high temperatures (e.g. ABI4, ABI5), the molecular cascade in response to cold stress (e.g. CBF1, ICE1) and hypotheses on changes in cell elongation (e.g. GASA1, AtEXPA11) with changes in temperatures based on studies at the whole plant scale. PMID:20878383

Dias, Paula Menna Barreto; Brunel-Muguet, Sophie; Durr, Carolyne; Huguet, Thierry; Demilly, Didier; Wagner, Marie-Helene

2010-01-01

76

Effect of temperature on spore germination and vegetative cell growth of Clostridium botulinum.  

PubMed Central

Spore germination and vegetative growth of Clostridium botulinum type E strain VH at 2 to 50 degrees C were studied. At all of these temperatures, germination began immediately after the addition of the spores to the germination medium. Microscopic observations during germination revealed three types of spores: phase bright (ungerminated), phase variable (partially germinated), and phase dark (fully germinated). At all temperatures except 50 degrees C, there was a pronounced lag between the initial appearance of phase-variable spores and their eventual conversion to phase-dark spores. The number of partially germinated spores increased steadily, reaching 40 to 60% by 18 to 21 h of incubation. During this time, phase-dark, fully germinated spores developed slowly and did not exceed 28% in any of the samples. At 18 to 26 h of incubation, the rate of full germination increased abruptly four-fold. There was extensive and relatively rapid germination at 2 degrees C, the lowest temperature tested, yielding about 60% phase-variable spores by 18 h, which became phase-dark by 26 h of incubation. The optimum temperature for partial and full germination was consistently 9 degrees C. Germination at 50 degrees C was exceptionally rapid and was completed within 1 to 2 h, although 40% remained phase bright. Vegetative cells showed detectable growth at 6 to 41 degrees C, with a distinct optimum at 32.5 degrees C. No growth occurred at 50 degrees C, and only marginal growth was observed at 6 to 14 degrees C. The psychrophilic nature of the germination process coupled with the cold tolerance of vegetative growth appears to give C. botulinum type E an advantage in cold climates as well as in cold-stored foods. PMID:7036898

Grecz, N; Arvay, L H

1982-01-01

77

EFFECTS OF ALUMINIUM (Al 3+ ) ON SEED GERMINATION AND SEEDLING GROWTH OF WHEAT (TRITICUM AESTIVUM L.)  

Microsoft Academic Search

Effects of different concentrations of aluminium (Al 3+ ) on seed germination of high yielding varieties of wheat (Triticum aestivum L.) were investigated. Al 3+ at 500 ppm had inhibitory effect on seed germination, seedling growth and its dry matter. Relatively higher root and shoot dry matter in Sonlika, Fang-60 and lower in Baw-923 and Protiva were found. Root growth

A. N. M. ALAMGIR; SUFIA AKHTER

2009-01-01

78

Enhancement in the germination, growth and yield of okra (Abelmoschus esculentus) using pre-sowing magnetic treatment of seeds.  

PubMed

The effect of pre-sowing magnetic treatments was investigated on germination, growth and yield of okra (Abelmoschus esculentus cv. Sapz pari). The dry okra seeds were exposed to sinusoidal magnetic field induced by an electromagnet. The average magnetic field exposure was 99 mT for 3 and 11 min and seeds with no magnetic field treatment were considered as control. Both treated and non-treated seeds were sown in experimental plots (120 m2) under similar conditions. Samples were collected at regular intervals for statistical analysis. A significant increase (P < 0.05) was observed in germination percentage, number of flowers per plant, leaf area (cm2), plant height (cm) at maturity, number of fruits per plant, pod mass per plant and number of seeds per plant. The 99 mT for 11 min exposure showed better results as compared to control. PMID:22803337

Naz, Afshan; Jamil, Yasir; ul Haq, Zia; Iqbal, Munawar; Ahmad, Muhammad Raza; Ashraf, Muhammad Irfan; Ahmad, Rasheed

2012-06-01

79

OSMOTIC STRESS-INDUCED CHANGES IN GERMINATION, GROWTH AND SOLUBLE SUGAR CONTENT OF SORGHUM BICOLOR (L.) MOENCH SEEDS  

Microsoft Academic Search

Summary. The effect of osmotic stress on germination, growth and soluble sugar content in Sorghum bicolor (L.) Moench cv. CSH 9 seeds and seedling components (endosperm and embryos) during early germination was inves- tigated. Under stress conditions germination decreased markedly, whereas the control at the same time reached its maximum germination (99%). A high percentage (67%) of ungerminated seeds from

Prabhjot Kaur Gill; Arun Dev Sharma; Prabhjeet Singh; Sukdev Singh Bhullar

2002-01-01

80

Allelopathic effects of mesquite ( Prosopis juliflora ) foliage on seed germination and seedling growth of bermudagrass ( Cynodon dactylon )  

Microsoft Academic Search

Allelopathic effects of aqueous extracts of 10, 20, 30, 40, 50 and 60g dry mesquite (Prosopis juliflora) leaves in a litre of distilled water on seed germination and early growth of bermudagrass (Cynodon dactylonCommon Bermuda) at 30C were investigated. The final germination percentage and the germination rate, as judged by corrected germination rate index (CGRI) and to a lesser extent

A. I. Al-Humaid; M. O. A. Warrag

1998-01-01

81

Allelopathic effects of Juglone and decomposed walnut leaf juice on muskmelon and cucumber seed germination and seedling growth  

Microsoft Academic Search

In this study, effects of juglone and decomposed walnut leaf juice on muskmelon (Cucumis melo cv. Galia) and cucumber (Cucumis sativus cv. Beith Alpha) seed germination percentage and post- germination seedling growth were investigated. Decomposition was carried out by keeping the leaves in distilled water. Muskmelon and cucumber seeds were germinated in Petri dishes at 25C. Seed germination, seedling elongation

I. Terzi

2008-01-01

82

Responses of seed germination, seedling growth, and seed yield traits to seed pretreatment in maize (Zea mays L.).  

PubMed

A series of seed priming experiments were conducted to test the effects of different pretreatment methods to seed germination, seedling growth, and seed yield traits in maize (Zea mays L.). Results indicated that the seeds primed by gibberellins (GA), NaCl, and polyethylene glycol (PEG) reagents showed a higher imbibitions rate compared to those primed with water. The final germination percentage and germination rate varied with different reagents significantly (P < 0.05). The recommended prime reagents were GA at 10?mg/L, NaCl at 50?mM, and PEG at 15% on account of germination experiment. 15% PEG priming reagent increased shoot and root biomass of maize seedling. The shoot biomass of seedlings after presoaking the seeds with NaCl reagent was significantly higher than the seedlings without priming treatment. No significant differences of plant height, leaf number, and hundred-grain weight were observed between control group and priming treatments. Presoaking with water, NaCl (50?mM), or PEG (15%) significantly increased the hundred-grain weight of maize. Therefore, seed pretreatment is proved to be an effective technique to improve the germination performance, seedling growth, and seed yield of maize. However, when compared with the two methods, if immediate sowing is possible, presoaking is recommended to harvest better benefits compared to priming method. PMID:25093210

Tian, Yu; Guan, Bo; Zhou, Daowei; Yu, Junbao; Li, Guangdi; Lou, Yujie

2014-01-01

83

Microgravity Effects on Plant Growth and Lignification  

NASA Astrophysics Data System (ADS)

Lignin is a major cellular component of higher plants. One function of lignin is to support vertical plant growth in a gravity environment. Various investigators working in the 1 g environment have concluded that lignification is influenced by gravity. An experiment was designed for flight on Spacelab II to determine the effect of microgravity on lignification in young plant seedlings. A secondary objective of the experiment was to examine the effect of microgravity on overall seedling growth. Mung bean and oat seeds germinated and the seedlings grew during the Spacelab II mission. Growth of flight mung bean and oat seedlings, however, was slower, and the seedlings exhibited stem and root orientation difficulties. Flight pine seedlings were similar in appearance and growth to 1 g controls. The rate of lignin formation in seedlings grown in space was significantly less in all three species in comparison to 1 g controls. The experiment provided direct evidence that lignification is slowed in a microgravity environment.

Cowles, Joe R.; Lemay, Richard; Jahns, Gary

1988-12-01

84

Effect of electroplating factory effluent on the germination and growth of hyacinth bean and mustard. [Dolichos lablab; Brassica compestris  

SciTech Connect

The effect of electroplating factory effluent in different concentrations (viz., 0.1, 0.2, 0.4, 0.6, 0.8, 1.0, 1.5, 2.0, 2.5, 3.0, and 4.0%) on the germination and growth of hyacinth beans (Dolichos lablab) and mustard seeds (Brassica compestris) was studied. The germination of seeds was delayed with the increase of effluent concentration and the germination of mustard seeds was totally inhibited at 1.5% effluent concentration while hyacinth bean seeds tolerated the effluent up to 2.5% concentration. The metal content in the hyacinth bean plants increased with increasing effluent concentration but after 1.0% effluent concentration, the concentration of all the metals (Ca, Mg, Na, K, Cu, Zn, Fe) decreased in the plants except Cr, which increased throughout. Percentage germination, fresh weight, dry weight, root length, and shoot length of the plants were also analyzed. Cd, Ni, Co, Mn, and Pb were not detectable in the hyacinth bean plants.

Ajmal, M.; Khan, A.U.

1985-12-01

85

Effects of dehydration and exogenous growth regulators on dormancy, quiescence and germination of grape somatic embryos  

Microsoft Academic Search

SummaryDormant grape somatic embryos from five genetically distinct culture lines were subjected either to dehydration or exogenous\\u000a growth regulators (benzyladenine, gibberellin or abscisic acid). Of growth regulator treatments tested, benzyladenine resulted\\u000a in the highest germination rate but postgermination growth was abnormal. Abscisic acid treatment resulted in the least germination.\\u000a Dehydration for 21 d under 7595% relative humidity was effective only

D. J. Gray

1989-01-01

86

Nak1, an Essential Germinal Center (GC) Kinase Regulates Cell Morphology and Growth in Schizosaccharomyces pombe*  

E-print Network

in loss of cell polarity remain unclear. The p21-activated kinases (PAKs)1 have been implicatedNak1, an Essential Germinal Center (GC) Kinase Regulates Cell Morphology and Growth kinase belonging to the group II germinal center kinase (GCK) family, in Schizosac- charomyces pombe. We

Young, Dallan

87

Nitric oxide stimulates seed germination and counteracts the inhibitory effect of heavy metals and salinity on root growth of Lupinus luteus  

Microsoft Academic Search

Nitric oxide (NO) is a bioactive molecule, which in plants was found to function as prooxidant as well as antioxidant. In the present study, we found that NO donor sodium nitroprusside (SNP) stimulates seed germination and root growth of lupin (Lupinus luteus L. cv. Ventus). Seed germination is promoted at concentrations between 0.1and 800?M SNP in a dose-dependent manner. The

Ma?gorzata Kopyra; Edward A. Gw?d?

2003-01-01

88

Intersection of two signalling pathways: extracellular nucleotides regulate pollen germination and pollen tube growth via nitric oxide  

PubMed Central

Plant and animal cells release or secrete ATP by various mechanisms, and this activity allows extracellular ATP to serve as a signalling molecule. Recent reports suggest that extracellular ATP induces plant responses ranging from increased cytosolic calcium to changes in auxin transport, xenobiotic resistance, pollen germination, and growth. Although calcium has been identified as a secondary messenger for the extracellular ATP signal, other parts of this signal transduction chain remain unknown. Increasing the extracellular concentration of ATP?S, a poorly-hydrolysable ATP analogue, inhibited both pollen germination and pollen tube elongation, while the addition of AMPS had no effect. Because pollen tube elongation is also sensitive to nitric oxide, this raised the possibility that a connection exists between the two pathways. Four approaches were used to test whether the germination and growth effects of extracellular ATP?S were transduced via nitric oxide. The results showed that increases in extracellular ATP?S induced increases in cellular nitric oxide, chemical agonists of the nitric oxide signalling pathway lowered the threshold of extracellular ATP?S that inhibits pollen germination, an antagonist of guanylate cyclase, which can inhibit some nitric oxide signalling pathways, blocked the ATP?S-induced inhibition of both pollen germination and pollen tube elongation, and the effects of applied ATP?S were blocked in nia1nia2 mutants, which have diminished NO production. The concurrence of these four data sets support the conclusion that the suppression of pollen germination and pollen tube elongation by extracellular nucleotides is mediated in part via the nitric oxide signalling pathway. PMID:19363208

Reichler, Stuart A.; Torres, Jonathan; Rivera, Amy L.; Cintolesi, Viviana A.; Clark, Greg; Roux, Stanley J.

2009-01-01

89

Seed fate in the myrmecochorous Neotropical plant Turnera ulmifolia L., from plant to germination  

NASA Astrophysics Data System (ADS)

Myrmecochory (seed dispersal by ants) differs from other dispersal systems in a series of advantages offered by the ants to the plants. Here, seed fate, from fruit to germination, of the myrmecochorous Neotropical plant Turnera ulmifolia L. is described. Seed movement from the fruit to their germination was studied, using different measurements and experiments. The results show that a T. ulmifolia individual produces ca. 5000 seeds per year. The main pre-seed-fall predators are the larvae of the Microlepidopteran Crocidosema plebejana Zeller, which consumed 1% of the seeds on the plant. The red-land crab Gecarcinus lateralis (Freminville) consumed 19% of the seeds beneath the plant and was the main post-seed-fall predator. Seed removal by ants was recorded on and beneath the plant, and ants removed 49% of the total seed production. Considering the seed removal events, the ant Forelius analis contributed with 64% of the total number of events. F. analis took seeds to its nest and discarded 23% of the seeds collected. Germination of seeds collected by F. analis was two to four times higher than that of seeds with and without elaiosome, respectively. The relatively low seed predation was probably related to ant defense, associated with the presence of extrafloral nectaries in this plant and with seed removal on the plant. Our results suggest that F. analis is a quantitatively efficient but qualitatively inefficient seed disperser of T. ulmifolia.

Salazar-Rojas, Betzabeth; Rico-Gray, Vctor; Canto, Azucena; Cuautle, Mariana

2012-04-01

90

The influence of microbial associations on germination of wheat seeds and growth of seedlings under impact of zinc salts  

Microsoft Academic Search

The life support systems (LSS) for long-term missions are to use cycling-recycling systems, including biological recycling. Higher plants are the traditional regenerator of air and producer of food. They should be used in many successive generations of their reproduction in LSS.Studies of influence of microbial associations on germination of wheat seeds and on growth of seedlings under impact of heavy

L. A. Somova; N. S. Pechurkin

2009-01-01

91

Effect of silver nanoparticles on rice (Oryza sativa L. cv. KDML 105) seed germination and seedling growth.  

PubMed

With the advances in nanotechnology, silver nanoparticles (AgNPs) have been applied in many industries, increasing their potential exposure level in the environment, yet their environmental safety remains poorly evaluated. The possible effects of different sized AgNPs (20, 30-60, 70-120 and 150nm diameter) on jasmine rice, Oryza sativa L. cv. KDML 105, were investigated at different concentrations (0.1, 1, 10, 100 and 1000mg/L) upon seed germination and seedling growth. The results revealed that the level of seed germination and subsequent growth of those seedlings that germinated were both decreased with increasing sizes and concentrations of AgNPs. Based on the analysis of AgNPs accumulation in plant tissues, it implied that the higher uptake was found when the seeds were treated with the smaller AgNPs, 20nm diameter AgNPs, but it was trapped in the roots rather than transported to the leaves. These resulted in the less negative effects on seedling growth, when compared to the seed soaking with the larger AgNPs with 150nm diameter. The negative effects of AgNPs were supported by leaf cell deformation when rice seeds were treated with 150-nm-diameter AgNP at the concentration of 10 or 100mg/L during seed germination. These results further strengthen our understanding of environmental safety information with respect to nanomaterials. PMID:24726943

Thuesombat, Pakvirun; Hannongbua, Supot; Akasit, Sanong; Chadchawan, Supachitra

2014-06-01

92

A high-throughput seed germination assay for root parasitic plants  

PubMed Central

Background Some root-parasitic plants belonging to the Orobanche, Phelipanche or Striga genus represent one of the most destructive and intractable weed problems to agricultural production in both developed and developing countries. Compared with most of the other weeds, parasitic weeds are difficult to control by conventional methods because of their life style. The main difficulties that currently limit the development of successful control methods are the ability of the parasite to produce a tremendous number of tiny seeds that may remain viable in the soil for more than 15 years. Seed germination requires induction by stimulants present in root exudates of host plants. Researches performed on these minute seeds are until now tedious and time-consuming because germination rate is usually evaluated in Petri-dish by counting germinated seeds under a binocular microscope. Results We developed an easy and fast method for germination rate determination based on a standardized 96-well plate test coupled with spectrophotometric reading of tetrazolium salt (MTT) reduction. We adapted the Mosmanns protocol for cell cultures to germinating seeds and determined the conditions of seed stimulation and germination, MTT staining and formazan salt solubilization required to obtain a linear relationship between absorbance and germination rate. Doseresponse analyses were presented as applications of interest for assessing half maximal effective or inhibitory concentrations of germination stimulants (strigolactones) or inhibitors (ABA), respectively, using four parameter logistic curves. Conclusion The developed MTT system is simple and accurate. It yields reproducible results for germination bioassays of parasitic plant seeds. This method is adapted to high-throughput screenings of allelochemicals (stimulants, inhibitors) or biological extracts on parasitic plant seed germination, and strengthens the investigations of distinctive features of parasitic plant germination. PMID:23915294

2013-01-01

93

Douglas-Fir in Northern California: Effects of Shade on Germination, Survival, and Growth.  

National Technical Information Service (NTIS)

Effects of four light intensities on germination, survival, and early growth of Douglas-fir (Pseudotsuga menziesii) were studied on south-facing cutblocks in northwestern California. Tested were four shade intensities: 0, 25, 50, and 75 percent. On seeded...

R. O. Strothmann

1972-01-01

94

Plant Growth and Hormones 102 Plant Growth and Hormones  

E-print Network

Plant Growth and Hormones 102 Plant Growth and Hormones Because plants have so many repeating parts does your data compare to that of other groups in your lab? #12;Plant Growth and Hormones 103 Plant Hormones Hormones are chemical substances that are produced in one tissue and transported to another, where

Koptur, Suzanne

95

Effect of salt stress on germination and seedling growth of Prosopis juliflora (Sw.)  

Microsoft Academic Search

The present study was conducted to evaluate the effect of different concentrations of salts on seed germination and seedling\\u000a growth of Prosopis juliflora. The experiment was carried out in Forestry Laboratory at Sari Agricultural Sciences and Natural Resources University, Iran.\\u000a The collected seeds were treated with boiling water and H2SO4 then left to germinate in controlled growth chamber. Seed were

Seyed Mohammad Hosseini Nasr; Aidin Parsakhoo; Hamed Naghavi; Sekineh Kiani Savad Koohi

96

Dispersal of wetland plant seeds by mallards: Influence of gut passage on recovery, retention, and germination  

Microsoft Academic Search

Seed dispersal is an important process for plants, but may be particularly important for plants occurring in spatially isolated\\u000a habitats like wetlands. Variation in the geographic distribution of wetland plant species may be strongly influenced by their\\u000a ability to use waterbirds, particularly waterfowl to enhance dispersal. We used controlled feeding and germination experiments\\u000a to investigate recovery, retention time, and germination

Chanpen Wongsriphuek; Bruce D. Dugger; Anne M. Bartuszevige

2008-01-01

97

Lead phytotoxicity on wheat ( Triticum aestivum L.) seed germination and seedlings growth  

Microsoft Academic Search

Lead (Pb) is an environmental pollutant extremely toxic to plants and other living organisms including humans. To assess Pb phytotoxicity, experiments focusing on germination of wheat seeds were germinated in a solution containing Pb (NO3)2 (0.05; 0.1; 0.5; 1g\\/L) during 6days. Lead accumulation in seedlings was positively correlated with the external concentrations, and negatively correlated with morphological parameters of plant

Mostafa Lamhamdi; Ahmed Bakrim; Ahmed Aarab; Ren Lafont; Fouad Sayah

2011-01-01

98

Toxic effects of heavy metals (Cd, Cr and Pb) on seed germination and growth and DPPH-scavenging activity in Brassica rapa var. turnip.  

PubMed

Toxicity of heavy metal is a wide spread environmental problem affecting all life forms including plants. In the present study the toxic effects of heavy metals, cadmium (Cd), chromium (Cr) and lead (Pb) on seed germination rate (%), germination index (G-index) and growth (mm) of Brassica rapa var. turnip have been investigated. The seeds were soaked either in distilled water (control) or in aqueous solutions of Cd, Cr and Pb (1 g/l, 2.5 g/l and 5 g/l) at 4C in dark for 24 hours. Prior to inoculation onto MS0 medium, the soaked seeds were either washed with sterile distilled water or inoculated without washing on solidified MS0 medium at 25 2C with 16/8-hour photoperiod in a growth chamber to germinate in vitro. Such stress conditions revealed that by increasing the concentration of heavy metals, the germination rate (%), G-index value and growth (mm) decreased significantly, suggesting their toxic effect on B. rapa var. turnip. This study further revealed that experiment with seed washing resulted in less toxicity of selected heavy metals on germination and growth of B. rapa var. turnip, as compared to experiment without washing. However, the resulting toxicity order of the selected heavy metals remained the same (Cd>Cr>Pb). Significant decrease has been observed in seed viability and germination potential and finally heavy metals completely ceased further growth and development of plants. The 2, 2-diphenyl-1-picrylhydrazyl (DPPH)-scavenging activity revealed that significantly higher activity was observed in control plants without heavy metals treatment. Furthermore, the Cd-treated plants showed decreased antioxidant activity. Cr and Pb were less toxic as compared to Cd (control>Pb>Cr>Cd). This study revealed that selected heavy metals not only affected plant development but also disturbed plant metabolic pathways. PMID:22872632

Siddiqui, Maryam Mehmood; Abbasi, Bilal Haider; Ahmad, Nisar; Ali, Mohammad; Mahmood, Tariq

2014-04-01

99

Irrigation and fertilization effects on seed number, size, germination and seedling growth: implications for desert shrub establishment.  

PubMed

Plants with limited resources adjust partitioning among growth, survival, and reproduction. We tested the effects of water and nutrient amendments on seed production, size, and quality in Sarcobatus vermiculatus (greasewood) to assess the magnitude and importance of changes in reproductive partitioning. In addition, we assessed interactions among the environment of seed-producing plants (adult plant scale), seed size, and seedling microenvironment (seedling scale) on successful seedling establishment. Interactions of these factors determine the scale of resource heterogeneity that affects seedling establishment in deserts. Both total number of seeds produced per plant and seed quality (weight and germination) increased significantly in the enriched treatment in a 3-year field experiment. Seedling length 3 days after germination and seed N concentration, other measures of seed quality, were higher for seed from both irrigated and enriched plants than for seed from control plants. Field S. vermiculatus seed production and quality can be substantially increased with irrigation and nutrient enrichment at the adult plant scale and this allows management of seed availability for restoration. However, based on a greenhouse study, seedling environment, not the environment of the seed-producing plant or seed size, was the most important factor affecting seedling germination, survival, and growth. Thus it appears that production of more seed may be more important than improved seed quality, because higher quality seed did not compensate for a low-resource seedling environment. For both natural establishment and restoration this suggests that heterogeneity at the scale of seedling microsites, perhaps combined with fertilization of adult shrubs (or multi-plant patches), would produce the greatest benefit for establishing seedlings in the field. PMID:18481096

Breen, A N; Richards, J H

2008-08-01

100

Effect of Light Crude Oil-Contaminated Soil on Growth and Germination of Festuca arundinacea  

NASA Astrophysics Data System (ADS)

In this study the effect of different concentrations of light crude oil (up to 10%) on the growth and germination of Festuca arundinacea (Tall fescue) was studied. Present results showed that the germination number and dry biomass of the plant decreased by increasing light crude oil concentration in the soil. The biomass was higher in 1% crude oil sample while it was lower in 10% crude oil sample. The length of leaves reduced in higher crude oil concentration in comparison with the control. Total and oil-degrading colony count of soil showed that the microbial population in 7 and 10% samples was higher than the control and low concentrations of crude oil (1 and 3% samples). The crude oil reduction in the vegetated and the non-vegetated samples was higher in 1% sample. All vegetated samples had higher crude oil reduction than non-vegetated samples. The higher reduction was occurred at 1% sample, while the lower reduction was seen at 10% sample.

Minai-Tehrani, Dariush; Shahriari, Malek-Hossein; Savaghebi-Firoozabadi, Gholamreza

101

Changes in germination, growth and soluble sugar contents of Sorghum bicolor (L.) Moench seeds under various abiotic stresses  

Microsoft Academic Search

The effect of various abiotic stresses on germination rate, growth and soluble sugar content in Sorghum bicolor (L.) Moench cv. CSH 6 seed embryos and endosperm during early germination was investigated. Under stress conditions germination, water potential and tissue water content decreased markedly. Subsequently, this reduction resulted in marked decreases in fresh weight both in embryos and endosperm. Conversely, a

Prabhjot Kaur Gill; Arun Dev Sharma; Prabhjeet Singh; Sukhdev Singh Bhullar

2003-01-01

102

Effects of gamma rays irradiation on seed germination and growth of hard wheat  

Microsoft Academic Search

The effects of irradiation with low doses (0, 10, 20 and 30Gy) of radioactive cobalt (60Co) ? rays on seed germination, shoot and epicotyl growth of hard wheat (Triticum durum Desf.) were investigated under laboratory and glasshouse conditions. Irradiated wheat seeds kept their germination speed\\u000a and capacity levels compared to the control. However, improvements of +18 and +32% were, respectively

Mongi Melki; A. Marouani

2010-01-01

103

Effects of low-level microwave radiation on germination and growth rate in corn seeds  

Microsoft Academic Search

Experiments were conducted to investigate the effects of microwave radiation on germination and growth rate in corn seeds. Specimens were irradiated in an anechoic chamber, for 22 to 24 h, at CW power density levels from 10 mW\\/cm2to 30 mW\\/cm2. The radiation frequency was 9 GHz. Marked inhibition of seed germination was observed in radiated specimens, probably as a result

J. Bigu-Del-Blanco; J. M. Bristow; C. Romero-Sierra

1977-01-01

104

The influence of microbial associations on germination of wheat seeds and on the growth of seedlings under impact of Zink salts  

NASA Astrophysics Data System (ADS)

The life support systems LSS for long-term missions are to use cycling-recycling systems including biological recycling Higher plants are the traditional regenerator of air and producer of food They should be used in many successive generations of their reproduction in LSS Development and studies of influence of microbial associations on germination of wheat seeds and on growth of seedlings under impact of heavy metals has good prospects and necessity because of migration of heavy metals in LSS Microbial associations are able to stimulate plants growth to protect them from pathogenic organisms and from toxicity of heavy metals salts The goal of this work was to investigate microbial associations action on the germination of wheat seeds and on the growth of seedlings under impact of different concentrations of ZnSO 4 The results of investigations showed 1 Zink salt had negative action on germination of wheat seeds beginning with concentrations - 8 MPC Maximum Permissible Concentration and higher 2 Microbial associations concentrations -10 4 -- 10 6 cells ml were able to decrease partly or completely the negative action of ZnSO 4 on germination of wheat seeds 3 Concentrations 10 4 -- 10 5 cells ml of microbial associations were able to decrease the negative action of Zink salts intervals from 2 to 32 MPA on the growth and development of wheat plantlets during heterotrophic phase 4 Root system of plants was more sensible to the negative action of ZnSO 4 than shoots of plants

Somova, L. A.; Pechurkin, N. S.; Mikheeva, G. A.

105

The influence of microbial associations on germination of wheat seeds and on the growth of seedlings under impact of Zink salts  

Microsoft Academic Search

The life support systems LSS for long-term missions are to use cycling-recycling systems including biological recycling Higher plants are the traditional regenerator of air and producer of food They should be used in many successive generations of their reproduction in LSS Development and studies of influence of microbial associations on germination of wheat seeds and on growth of seedlings under

L. A. Somova; N. S. Pechurkin; G. A. Mikheeva

2006-01-01

106

Germination and Early Growth of Brassica juncea in Copper Mine Tailings Amended with Technosol and Compost  

PubMed Central

Mine tailings represent a serious threat to the environment and human health; thus their restoration has become a major concern. In this study, the interactions between Brassica juncea and different mine soil treatments were evaluated in order to understand their effect on germination and early growth. Three soil treatments containing 25% and 50% of technosol and 30% of compost were prepared. Germination and early growth were assessed in soil and pore water extracts from the treatments. Unlike the untreated mine soil, the three treatments allowed germination and growth, achieving levels comparable to those of seedlings from the same species developed in normal conditions. The seedlings grown in 50% of technosol and 30% of compost exhibited greater germination percentages, higher growth, and more efficient mechanisms against oxidative stress, ascribed to the organic matter and nutrients content of these treatments. Considering the unequivocal ability of B. juncea for phytoremediation, the results suggest that technosol and compost may be an auspicious solution to allow the germination and early growth of this species in mine tailings. PMID:25386602

Gonzlez, Lus

2014-01-01

107

Analysis of directional root growth patterns from corn and soybean seeds germinated in space  

NASA Astrophysics Data System (ADS)

The JOSE (JASON Outreach Seed Experiment) payload was the first plant experiment conducted on the International Space Station (ISS). It consisted of having an on-orbit watering of eight transparent seed pouches each of which contained 6 individual seeds of either soybean (Glycine max cv McCall) or corn ( Zea mays ). The seeds were glued to a germination paper substrate using a 1.2% guar glue solution. The payload was launched on the Orbiter Endeavour (STS-97; ISS Flight 4A) on 11/30/00 and transferred to the ISS on 12/8/00. The eight seed pouches were each watered with 12 mL of distilled water on 1/5/01. Two pouches containing corn plus two pouches containing soybean seeds were maintained in the light after watering. Two additional seed pouches of each species were maintained in the dark after watering. Digital photography was used to document the growth of the germinating seedlings in space. The images were down-linked to a world wide web site for dissemination to students. "Within" species differences (between the light and dark grown seedlings) as well as "between" species differences (comparing corn and soybean) were observed. By day 4 (post-imbibition) there was a clear phototropic effect in the light-grown corn seedlings, each, possessing a green shoot which grew upward towards the light source. In contrast, the dark-grown corn shoots were neither green (since chlorophyll synthesis had not been induced by light) nor were they growing in a uniform direction. For day 4 soybean seedlings, the only difference evident between those germinated under the light vs dark conditions was a slight greening up of the seeds maintained in the presence of light. For both the corn and soybean seedlings, roots grew in a random fashion, with some moving in an upward direction and others progressing downward, reflecting the lack of a gravitropic response which is the primary (earth-based) mechanism controlling the direction of root growth. By day 7 the initial 12 mL of water added to each pouch was greatly diminished, although noticeably less so in the soybean pouches. This was presumably due to the faster and overall greater growth exhibited by the corn seedlings, which resulted in a more rapid utilization of the available water. There was also a more pronounced greening-up of the light-exposed soybean seedlings than was evident at day 4, with both the cotylendons and hypocotyl regions showing signs of chlorophyll synthesis. This work was supported under NASA Contract NAS10-002001.

Levine, H.; Tynes, G.; Norwood, K.

108

The effects of salinity on aquatic plant germination and zooplankton hatching from two wetland sediments  

Microsoft Academic Search

SUMMARY 1. The effect of increasing salinity on the emergence of zooplankton eggs and the germination of aquatic plant seeds from the sediment of two wetlands was examined. Salinity was found to cause reductions in species richness and abundance of aquatic plants and zooplankton at salinities between 1000 and 5000 mg L)1. Aquatic plants also had an associated decrease in

DARYL L. N IELSEN; K ATHARINE; C ROSSLE ; K EN H ARRIS; MICHAEL H EALEY; I RENE J AROSINSKI

2003-01-01

109

Germination and growth of lettuce (Lactuca sativa) at low atmospheric pressure  

NASA Technical Reports Server (NTRS)

The response of lettuce (Lactuca sativa L. cv. Waldmann's Green) to low atmospheric pressure was examined during the initial 5 days of germination and emergence, and also during subsequent growth to vegetative maturity at 30 days. Growth took place inside a 66-l-volume low pressure chamber maintained at 70 kPa, and plant response was compared to that of plants in a second, matching chamber that was at ambient pressure (approximately 101 kPa) as a control. In other experiments, to determine short-term effects of low pressure transients, plants were grown at ambient pressure until maturity and then subjected to alternating periods of 24 h of low and ambient atmospheric pressures. In all treatments the partial pressure of O2 was maintained at 21 kPa (approximately the partial pressure in air at normal pressure), and the partial pressure of CO2 was in the range 66.5-73.5 Pa (about twice that in normal air) in both chambers, with the addition of CO2 during the light phase. With continuous exposure to low pressure, shoot and root growth was at least as rapid as at ambient pressure, with an overall trend towards slightly greater performance at the lower pressure. Dark respiration rates were greater at low pressure. Transient periods at low pressure decreased transpiration and increased dark respiration but only during the period of exposure to low pressure. We conclude that long-term or short-term exposure to subambient pressure (70 kPa) was without detectable detriment to vegetative growth and development.

Spanarkel, Robert; Drew, Malcolm C.

2002-01-01

110

Inhibition of radish germination and root growth by coumarin and phenylpropanoids  

Microsoft Academic Search

Thirteen natural and synthetic phenylpropanoids as well as coumarin (2104M) were tested for their biological activity on radish germination and subsequent root growth in light and darkness. Coumarin was the most potent inhibitor. With some exceptions, phenylpropanoids with a carboxylic group in the side chain inhibited root growth. Coumarin was formed spontaneously by photooxidation of 2-hydroxycinnamic acid. Microscopic observations of

G. Aliotta; G. Cafiero; A. Fiorentino; S. Strumia

1993-01-01

111

Water Potential and Ionic Effects on Germination and Seedling Growth of Two Cold Desert Shrubs  

Microsoft Academic Search

We tested expectations that two desert shrubs would differ in germination and seedling relative growth rate (RGR) responses to Na and Cs stress. The study species, Chrysothamnus nauseosusssp. consimilis and Sarcobatus vermiculatus (hereafter referred to by genus), differ in their distribution along salinity gradients, with Chrysothamnusinhabiting only less saline areas. In growth chamber studies, declining Cs (20.82 to 22.71 MPa)

Geraldine L. Dodd; Lisa A. Donovan

1999-01-01

112

Overexpression of Arabidopsis Plasmodesmata Germin-Like Proteins Disrupts Root Growth and Development[C][W  

PubMed Central

In plants, a population of non-cell-autonomous proteins (NCAPs), including numerous transcription factors, move cell to cell through plasmodesmata (PD). In many cases, the intercellular trafficking of these NCAPs is regulated by their interaction with specific PD components. To gain further insight into the functions of this NCAP pathway, coimmunoprecipitation experiments were performed on a tobacco (Nicotiana tabacum) plasmodesmal-enriched cell wall protein preparation using as bait the NCAP, pumpkin (Cucurbita maxima) PHLOEM PROTEIN16 (Cm-PP16). A Cm-PP16 interaction partner, Nt-PLASMODESMAL GERMIN-LIKE PROTEIN1 (Nt-PDGLP1) was identified and shown to be a PD-located component. Arabidopsis thaliana putative orthologs, PDGLP1 and PDGLP2, were identified; expression studies indicated that, postgermination, these proteins were preferentially expressed in the root system. The PDGLP1 signal peptide was shown to function in localization to the PD by a novel mechanism involving the endoplasmic reticulum-Golgi secretory pathway. Overexpression of various tagged versions altered root meristem function, leading to reduced primary root but enhanced lateral root growth. This effect on root growth was corrected with an inability of these chimeric proteins to form stable PD-localized complexes. PDGLP1 and PDGLP2 appear to be involved in regulating primary root growth by controlling phloem-mediated allocation of resources between the primary and lateral root meristems. PMID:22960910

Ham, Byung-Kook; Li, Gang; Kang, Byung-Ho; Zeng, Fanchang; Lucas, William J.

2012-01-01

113

Pollen germination and pollen tube growth in Fraxinus pennsylvanica  

Microsoft Academic Search

With regard to adaptation of green ash (Fraxinus pennsylvanica\\u000a Marshall) to ecological conditions in Croatia, pollen germination and pollen tube length after 2, 4 and 6 hours were examined in vitro at 10, 15, 20 and 25C during two years 2001 and 2002. Narrow leaved ash (F. angustifolia\\u000a Vahl) pollen served as a control in 2002. The year, time and

Dario Kremer; Tomislav Jemri?

2006-01-01

114

Plant growth in expanded perlite  

Microsoft Academic Search

The chemical and physical properties of expanded perlite as a growth medium are described.The growth of cress in perlite receiving additions of inorganic fertilisers is described and assessed. Only slightly less growth was made in perlite fortified with plant nutrients than in a good potting soil.The medium is simple to handle and is suitable for the growth of plants in

T. M. Morrison; D. C. McDonald; Jean A. Sutton

1960-01-01

115

Lead-induced phytotoxicity mechanism involved in seed germination and seedling growth of wheat ( Triticum aestivum L.)  

Microsoft Academic Search

The mechanism of lead-inhibitory effects on seed germination and seedling growth was investigated in wheat cv. Xihan 2 subjected to different Pb(NO3)2 concentrations. High concentrations of lead and exogenous H2O2 significantly inhibited seed germination and the growth of roots and shoots. Dimethylthiourea, catalase or diphenylene iodonium could reverse lead-inhibitory effects on seed germination. Significant elevated H2O2 generation was observed in

Yingli Yang; Xueling Wei; Jin Lu; Jia You; Wenrui Wang; Ruxia Shi

2010-01-01

116

In vitro germination of nonphotosynthetic, myco-heterotrophic plants stimulated by fungi isolated from the adult plants  

Microsoft Academic Search

summary Sarcodes sanguinea and Pterospora andromedea (Ericaceae, Monotropoideae) are nonphotosynthetic myco- heterotrophic plants. Recent studies have shown that the roots of the adult plants are always associated with closely related but exclusive sets of Rhizopogon species (Basidiomycota, Boletales) from section Amylopogon. We have isolated Rhizopogon species that were associated with the adult plants and used them to germinate seeds under

THOMAS D. B RUNS; DAVID J. R EAD

2000-01-01

117

Seeds Use Temperature Cues to Ensure Germination under Nurse-plant Shade in Xeric Kalahari Savannah  

PubMed Central

Background and Aims In arid environments many plant species are found associated with the canopies of woody perennials. Favourable conditions for establishment under canopies are likely to be associated with shade, but under canopies shade is distributed patchily and differs in quality. Diurnal temperature fluctuations and maximum temperatures could be reliable indicators of safe sites. Here, an examination is made as to whether canopy-associated species use temperature cues to germinate in shade patches, rather than matrix areas between trees. Methods The study was carried out in arid southern Kalahari savannah (Republic of South Africa). Perennial and annual species associated with Acacia erioloba trees and matrix species were germinated at temperature regimes resembling shaded and unshaded conditions. Soil temperature was measured in the field. Key Results Germination of all fleshy-fruited perennial acacia-associated species and two annual acacia-associated species was inhibited by the temperature regime resembling unshaded conditions compared with at least one of the regimes resembling shaded conditions. Inhibition in perennials decreased with seed mass, probably reflecting that smaller seedlings are more vulnerable to drought. Germination of matrix species was not inhibited by the unshaded temperature regime and in several cases it increased germination compared with shaded temperature regimes or constant temperature. Using phylogenetically independent contrasts a significant positive relationship was found between canopy association and the germination at shade temperatures relative to unshaded temperatures. Conclusions The data support the hypothesis that canopy species have developed mechanisms to prevent germination in open sun conditions. The results and data from the literature show that inhibition of germination at temperature regimes characteristic of open sun conditions can be found in fleshy-fruited species of widely divergent taxonomic groups. It is predicted that germination mechanisms to detect canopy shade based on temperature cues are widespread in species depending on nurse plants, especially bird-dispersed species. PMID:17259226

Kos, Martijn; Poschlod, Peter

2007-01-01

118

[Research progress in seegrass seed dormancy, germination, and seedling growth and related affecting factors].  

PubMed

Seagrass bed is the main primary producer in coastal areas, having highly ecological and economical values, and being one of the most important shallow-marine ecosystems. This paper reviewed the research progress in the seed dormancy, germination, and seedling growth of seagrass and related affecting factors, summarized the seed dormancy modes and durations and their affecting factors, and discussed the effects of water salinity, temperature, transparency, hormone, dissolved oxygen, and population structure on the seed germination and the seedling survival and growth. Some issues in related researches and several research directions in the future were prospected. PMID:22303688

Zhang, Pei-Dong; Sun, Yan; Niu, Shu-Na; Zhang, Xiu-Mei

2011-11-01

119

Sensitivity of the Entomogenous Fungus Beauveria bassiana to Selected Plant Growth Regulators and Spray Additives  

PubMed Central

Mefluidide was the only one of four plant growth regulators that caused little to no significant inhibition of in vitro germination and growth of the entomogenous fungus Beauveria bassiana. Silaid, paclobutrazol, and flurprimidol significantly inhibited germination and growth. Mortality of fall armyworm, Spodoptera frugiperda, resulting from B. bassiana was significantly reduced when larvae were exposed to conidia plus soil treated with paclobutrazol. Larval mortality resulting from conidia plus soil treated with mefluidide did not differ significantly from mortality resulting from untreated conidia. Triton CS-7 was the only one of eight spray adjuvants that significantly inhibited germination of B. bassiana conidia. PMID:16347095

Storey, Greggory K.; Gardner, Wayne A.

1986-01-01

120

Effect of BPA on the germination, root development, seedling growth and leaf differentiation under different light conditions in Arabidopsis thaliana.  

PubMed

Bisphenol A (BPA) is a well-known environmental toxic substance, which exerts unfavorable effects through endocrine disruptor (ER)-dependent and ER-independent mechanisms to threaten ecological systems seriously. BPA may also interact with other environmental factors, such as light and heavy metals, to have a synergetic effect in plants. However, there is little data concerning the toxic effect of BPA on the primary producers-plants and its possible interaction with light-dependent response. Here, the effects of BPA on germination, fresh weight, tap root length, and leaf differentiation were studied in Arabidopsis thaliana under different parts of light spectrum (dark, red, yellow, green, blue, and white light). Our results showed that low-dose BPA (1.0, 5.0 M) caused an increase in the fresh weight, the tap root length and the lateral root formation of A. thaliana seedlings, while high-dose BPA (10.0, 25.0 M) show an inhibition effect in a dose-dependent manner. Unlike karrikins, the effects of BPA on germination fresh weight and tap roots length under various light conditions are similar, which imply that BPA has no notable role in priming light response in germination and early seedling growth in A. thaliana. Meanwhile, BPA exposure influences the differentiation of A. thaliana leaf blade significantly in a light-dependent manner with little to no effect in dark and clear effect under red illumination. PMID:24206833

Pan, Wen-Juan; Xiong, Can; Wua, Qiu-Ping; Liu, Jin-Xia; Liao, Hong-Mei; Chen, Wei; Liu, Yong-Sheng; Zheng, Lei

2013-11-01

121

Germination and seedling growth of the water cress Rorippa sp. exposed to the chelant [S,S]-EDDS.  

PubMed

With the implementation of the new EU environmental framework directives, high tier risk assessments of chemicals will be increasingly needed. For high production chemicals, additional tests will complement the standard battery for aquatic toxicity assessments (daphnids, algae, and fish). In the context of a new chemical notification at the European Union level, we have developed a seed germination and root elongation toxicity test with the freshwater aquatic plant Rorippa nasturtium-aquaticum (water cress) to confirm the low environmental risk of the chelant [S,S]-EDDS. A 14 day semi-static growth inhibition test was conducted with daily renewal of the test solution. No concentration related inhibition was found on the basis of any of the criteria investigated, i.e., time and extent of germination, biomass, number of leaves, stalk and root lengths. The no-observed effect concentration was considered to be >or=387 mg SS-EDDS/l. Although germination was selected as an appropriate endpoint to assess the effect of a chelant on an aquatic plant (other endpoints would have been dependant on essential metals that are chelated in standard culture tests), the absence of dose related effects requires further tests with higher exposure concentrations and/or other toxicant(s) to assess the validity of the test as a general tool for aquatic risk assessment. PMID:16530249

Temara, Ali; Bowmer, Tim; Rottiers, Andre; Robertson, Steve

2006-10-01

122

Studies on the effects of chromium stress on the germination and growth of Phaseolus mungo: influence of chromium resistant Pseudomonad  

Microsoft Academic Search

Effects of chromium resistant strains of Pseudomonad, Scr 1 and Scr 2 on the germination of seeds and growth of the common blackgram Phaseolus mungo growing under chromium stress have been evaluated. Scr 1 and Scr 2 were isolated from chromium rich wastewaters and rhizosphere of Euphorbia hirta, employing standard methods. Rate of germination and growth of P. mungo exposed

M. Rajkumar; R. Nagendran

2000-01-01

123

Does passage time through the lizard Podarcis lilfordi's guts affect germination performance in the plant Withania frutescens?  

NASA Astrophysics Data System (ADS)

I tested predictions of the hypothesis that a longer seed passage time through the gut of the lizard Podarcis lilfordi enhances germination performance in the plant Withania frutescens. I compared germination success and germination time between seeds that were ingested by lizards and control seeds that were not. I also explored relationships between natural variation in seed passage time and germination performance. Germination success did not differ between ingested (63 %) and non-ingested seeds (56 %); there was no significant relationship between germinability and retention time. Germination time did not differ between ingested and non-ingested seeds, and was unrelated to retention time. Hence, I found no support for the hypothesis that prolonged retention times should improve germination performance. In addition, this is a pilot study stressing the importance of reptiles as seed dispersers, at least in certain habitats.

Castilla, Aurora M.

2000-03-01

124

Impacts of Carpobrotus edulis (L.) N.E.Br. on the germination, establishment and survival of native plants: a clue for assessing its competitive strength.  

PubMed

Does Carpobrotus edulis have an impact on native plants? How do C. edulis' soil residual effects affect the maintenance of native populations? What is the extent of interspecific competition in its invasion process? In order to answer those questions, we established pure and mixed cultures of native species and C. edulis on soil collected from invaded and native areas of Mediterranean coastal dunes in the Iberian Peninsula. We examined the impact of the invader on the germination, growth and survival of seeds and adult plants of two native plant species (Malcolmia littorea (L.) R.Br, and Scabiosa atropurpurea L.) growing with ramets or seeds of C. edulis. Residual effects of C. edulis on soils affected the germination process and early growth of native plants in different ways, depending on plant species and density. Interspecific competition significantly reduced the germination and early growth of native plants but this result was soil, density, timing and plant species dependent. Also, at any density of adult individuals of C. edulis, established native adult plants were not competitive. Moreover, ramets of C. edulis had a lethal effect on native plants, which died in a short period of time. Even the presence of C. edulis seedlings prevents the recruitment of native species. In conclusion, C. edulis have strong negative impacts on the germination, growth and survival of the native species M. littorea and S. atropurpurea. These impacts were highly depended on the development stages of native and invasive plants. Our findings are crucial for new strategies of biodiversity conservation in coastal habitats. PMID:25210924

Novoa, Ana; Gonzlez, Lus

2014-01-01

125

Nod factors stimulate seed germination and promote growth and nodulation of pea and vetch under competitive conditions.  

PubMed

Nod factors are lipochitooligosaccharide (LCO) produced by soil bacteria commonly known as rhizobia acting as signals for the legume plants to initiate symbiosis. Nod factors trigger early symbiotic responses in plant roots and initiate the development of specialized plant organs called nodules, where biological nitrogen fixation takes place. Here, the effect of specific LCO originating from flavonoid induced Rhizobium leguminosarum bv. viciae GR09 culture was studied on germination, plant growth and nodulation of pea and vetch. A crude preparation of GR09 LCO significantly enhanced symbiotic performance of pea and vetch grown under laboratory conditions and in the soil. Moreover, the effect of GR09 LCOs seed treatments on the genetic diversity of rhizobia recovered from vetch and pea nodules was presented. PMID:21723717

Kidaj, Dominika; Wielbo, Jerzy; Skorupska, Anna

2012-03-20

126

Flavonols Stimulate Development, Germination, and Tube Growth of Tobacco Pollen 1  

PubMed Central

The effect of anther-derived substances on pollen function was studied using pollen produced by in vitro culture of immature pollen of tobacco (Nicotiana tabacum L.) and petunia (Petunia hybrida). Addition of conditioned medium consisting of diffusates from in situ matured pollen strongly increased pollen germination frequency and pollen tube growth, as well as seed set after in situ pollination. Thin-layer chromatography and depletion of phenolic substances by Dowex treatment indicated that flavonols are present in the diffusate and may be the active compounds. When added to the germination medium, flavonols (quercetin, kaempferol, myricetin) but not other flavonoids strongly promoted pollen germination frequency and pollen tube growth in vitro. The best results were obtained at very low concentrations of the flavonols (0.15-1.5 ?m), indicating a signaling function. The same compounds were also effective when added during pollen development in vitro. Images Figure 1 Figure 5 PMID:16653074

Ylstra, Bauke; Touraev, Alisher; Moreno, Rosa Maria Benito; Stoger, Eva; van Tunen, Arjen J.; Vicente, Oscar; Mol, Joseph N. M.; Heberle-Bors, Erwin

1992-01-01

127

Leucanthemum vulgare lam. germination, growth and mycorrhizal symbiosis under crude oil contamination.  

PubMed

Oil contamination of soil limits plants' access to water and nutrients. Leucanthemum vulgare colonized by mycorrhizae could provide an effective tool in remedying oil contamination. Seeds of L. vulgare were planted in pots containing soil mixed with petroleum at 0, 2.5, 5, 7.5, and 10% w/w and propagules of mycorrhizal fungi. Plants were grown under ambient conditions for 16 weeks. Seed germination data were collected weekly for three weeks. Mycorrhizal percentage, spore counts, length and weight of roots and shoots were determined after harvesting. Results showed significant differences in seed germination rates between oil-treated, mycorrhizal and non-mycorrhizal plants. The overall germination rate was greater at 7.5% w/w crude oil contamination (p = 0.05) in mycorrhizal and non-mycorrhizal pots with significant differences between their respective Root:Shoot ratios (both length and weight). Results of this research showed L. vulgare could be germinated and grown in crude oil contaminated soils and could be used to augment plant establishment as part of phytoremediation practices. PMID:24933896

Noori, Azam Sadat; Maivan, Hassan Zare; Alaie, Ebrahim

2014-01-01

128

BOA detoxification of four summer weeds during germination and seedling growth.  

PubMed

A recent greenhouse study revealed a significant reduction of germination and growth of redroot pigweed (Amaranthus retroflexus) and common purslane (Portulaca oleracea) by rye mulch, whereas velvetleaf (Abutilon theophrasti) and common lambsquarters (Chenopodium album) were not suppressed. Since BOA detoxification by metabolic alteration may influence the relation between the benzoxazinoid content of the soil mulch and weed suppression, we tested the dynamics in BOA detoxification in different plant organs of three and 10-day-old seedlings of four warm season weeds incubated with five BOA concentrations (4, 20, 40, 80, and 200 ?mol g(-1) fresh weight). In addition, germination and length of 3-day-old seedlings were measured after exposure to 0, 0.3, 1.5, 3, 6, and 15 ?mol BOA. Finally, we tested the influence of the MDR translocator inhibitors verapamil, nifedipine, and the GST inhibitor ethycrynic acid on BOA accumulation and detoxification activity. Due to BOA-detoxification, all weeds were able to grow in environments with low BOA contents. At higher contents, Abutilon theophrasti and Chenopodium album had a better chance to survive because of highly active mechanisms that avoided the uptake of BOA (A. theophrasti) and of efficient detoxification activities in youngest seedlings (C. album). The interpretation of all of the data gave the following sequence of increasing sensitivity: A. theophrasti < C. album < P. oleracea ? A. retroflexus. The results were in agreement with recent findings of the suppression of these weeds by rye mulches and their benzoxazinoid contents. Our studies demonstrate for the first time that the detoxification of BOA influences the survival of certain weeds in environments enriched with this allelochemical. Therefore, detoxification processes affect the potential for weed suppression by soil allelochemicals in sustainable weed management. PMID:22614450

Schulz, Margot; Marocco, Adriano; Tabaglio, Vincenzo

2012-07-01

129

Germination and root elongation bioassays in six different plant species for testing Ni contamination in soil.  

PubMed

In vitro short-term chronic phytotoxicity germination and root elongation test were applied to test the effects of nickel (Ni) in seed germination and root elongation in six plants species: Cucumis sativus (Cucurbitaceae), Lepidium sativum and Brassica nigra (Brassicaceae), Trifolium alexandrinum and Medicago sativa (Fabaceae), Phacelia tanacetifolia (Boraginaceae). A naturally Ni rich soil was used to compare the results obtained. Unlike root elongation, germination was not affected by Ni in any of the six species tested. EC50 values, calculated on the root elongation, showed that Ni toxicity decreases in the following order: P. tanacetifolia > B. nigra > C. sativus > L. sativum > M. sativa > T. alexandrinum. The test conducted using soil elutriate revealed a significantly lower effect in both seed germination and root elongation when compared to the results obtained using untreated soil. Conversely, the test performed on soil confirmed the high sensitivity of C. sativus, P. tanacetifolia and L. sativum to Ni. PMID:24288040

Visioli, Giovanna; Conti, Federica D; Gardi, Ciro; Menta, Cristina

2014-04-01

130

Effect of aqueous extracts of allelopathic crops on germination and growth of Parthenium hysterophorus L  

Microsoft Academic Search

Herbicidal effects of aqueous root and shoot extracts of three allelopathic crops, viz. sunflower (Helianthus annuus L.), sorghum (Sorghum bicolor L.) and rice (Oryza sativa L.) were evaluated against germination and growth of the noxious alien weed Parthenium hysterophorus L. The study, carried out in petri dishes using 5, 10, 15, 20 and 25% (w\\/v) aqueous root and shoot extracts

A. Javaid; S. Shafique; R. Bajwa

2006-01-01

131

Effects of Salinity on Germination and Early Growth of Barley (Hordeum vulgare L.) Cultivars  

Microsoft Academic Search

This study was conducted to determine the effects of salinity on seed germination and early vegetative growth of nine genotypes of barley (5 landraces & 4 breeding lines). The genotypes were evaluated by several criteria, at four salt concentrations (0, 100, 150 & 200 mM) and four seawater concentrations (0, 20, 30 & 40%). The results revealed a large variability

SAID EL MADIDI; BRAHIM EL BAROUDI; FOUZIA BANI AAMEUR

132

Consumption of wheat seed reserves during germination and early growth as affected by soil water potential  

Microsoft Academic Search

Seed size and weight are important criteria for determining seedling vigour and stand establishment. Evolution of seed dry weight of wheat (Triticum aestivum L.) during germination and early growth was examined because poor stands are often associated with the depletion and exhaustion of seed reserves. Two laboratory experiments were conducted on filter paper and in soil at three water potentials

A. Bouaziz; D. R. Hicks

1990-01-01

133

Salinity effects on germination, growth, and seed production of the halophyte Cakile maritima  

Microsoft Academic Search

Cakile maritima (Brassicaceae) is a halophyte that thrives on dunes along the Tunisian seashore. Besides its ecological interest for soil fixation, this plant produces seeds rich in lipids (40% on dry weight basis), making it a potential source of oil for industrial use. The purpose of the present work was to study the salt tolerance of this species at germination,

Ahmed Debez; Karim Ben Hamed; Claude Grignon; Chedly Abdelly

2004-01-01

134

Students' Ideas about Plants and Plant Growth  

ERIC Educational Resources Information Center

Because the National Science Education Standards (1996) outline specific things K-8 students should know about plants, and previous data indicated that elementary students had difficulty understanding some major ideas about plants and plant growth, the authors of this article thought it appropriate to initiate an investigation to determine the

Barman, Charles R.; Stein, Mary; McNair, Shannan; Barman, Natalie S.

2006-01-01

135

Seed germination during floatation and seedling growth of Carapa guianensis , a tree from flood-prone forests of the Amazon  

Microsoft Academic Search

Carapa guianensis Aubl. (Meliaceae), a hard wood tree from the Brazilian Amazon, has large recalcitrant seeds that can germinate and establish in both flood-free (terra-firme) and flood-prone (vrzea) forests. These seeds, although large, can float. This study was designed to experimentally examine seed longevity under floating conditions ex-situ and its effects on subsequent germination and seedling growth. Many seeds germinated

Fbio R. Scarano; Tnia S. Pereira; Giselle Ras

2003-01-01

136

Pump up the volume - a central role for the plasma membrane H(+) pump in pollen germination and tube growth.  

PubMed

The plasma membrane H(+) ATPase is a member of the P-ATPase family transporting H(+) from the cytosol to the extracellular space and thus energizing the plasma membrane for the uptake of ions and nutrients. As a housekeeping gene, this protein can be detected in almost every plant cell including the exclusive expression of specific isoforms in pollen grains and tubes where its activity is a prerequisite for successful germination and growth of pollen tubes. This review summarizes the current knowledge on pollen PMH(+) ATPases and hypothesizes a central role for pollen-specific isoforms of this protein in tube growth. External as well as cytosolic signals from signal transduction and metabolic pathways are integrated by the PMH(+) ATPase and directly translated to tube growth rates, allocating the PMH(+) ATPase to an essential node in the signalling network of pollen tubes in their race to the ovule. PMID:24097309

Lang, Veronika; Pertl-Obermeyer, Heidi; Safiarian, Minou J; Obermeyer, Gerhard

2014-05-01

137

Detecting free radicals in biochars and determining their ability to inhibit the germination and growth of corn, wheat and rice seedlings.  

PubMed

Biochar can benefit human society as a carbon-negative material and soil amendment. However, negative biochar impacts on plant germination and growth have been observed, and they have not been fully explained. Therefore, protocols to avoid these risks cannot be proposed. We hypothesized that the free radicals generated during charring may inhibit plant germination and growth. Significant electron paramagnetic resonance (EPR) signals were observed in the biochars derived from several types of common biomass (corn stalk, rice, and wheat straws) and the major biopolymer components of biomass (cellulose and lignin), but not in the original materials, suggesting the ubiquitous presence of free radicals in biochars. EPR signal intensity increased with increasing pyrolysis temperature, and it was dominantly contributed by oxygen centered in the mixture of oxygen- and carbon-centered free radicals as the temperature increased. The free radicals in biochars induced strong OH radicals in the aqueous phase. Significant germination inhibition, root and shoot growth retardation and plasma membrane damage were observed for biochars with abundant free radicals. Germination inhibition and plasma membrane damage were not obvious for biochars containing low free radicals, but they were apparent at comparable concentrations of conventional contaminants, such as heavy metals and polyaromatic hydrocarbons. The potential risk and harm of relatively persistent free radicals in biochars must be addressed to apply them safely. PMID:24988274

Liao, Shaohua; Pan, Bo; Li, Hao; Zhang, Di; Xing, Baoshan

2014-08-01

138

Growth, Development and Reproduction -- Exploring and explaining germination, growth and development  

NSDL National Science Digital Library

A 32-page booklet, containing complete instructions for activities at each life cycle stage. The booklet also includes important background information about plant physiology and how to grow Fast Plants.A Growth, Development and Reproduction kit is available. You can also conduct all the investigations explained in the booklet using seeds from a packet of Standard Wisconsin Fast Plants seeds (or seeds from Fast Plants you grow yourself) and your own potting mix and growing system.Either way, you'll need to plan for providing adequate light. Learn about all these factors in the How to Grow files on this website.

Program, The W.

139

Effect of Fungicides and Plant Extracts on the Conidial Germination of Colletotrichum gloeosporioides Causing Mango Anthracnose  

PubMed Central

In Northern Bangladesh, generally mango trees are planted as agroforest that gives higher Net Present Value (NPV) than traditional agriculture. Mango anthracnose caused by Colletotrichum gloeosporioides Penz. is seen as a very destructive and widely distributed disease, which results in poor market value. Five fungicides such as Cupravit, Bavistin, Dithane M-45, Thiovit and Redomil were tested against conidial germination of C. gloeosporioides. Dithane M-45 and Redomil were the most effective when the conidia were immersed for 10~20 minutes at 500~1000 ppm concentrations. Antifungal activities of 13 plant extracts were tested against conidial germination of C. gloeosporioides. Conidial germination of C. gloeosporioides was completely inhibited in Curcuma longa (leaf and rhizome), Tagetes erecta (leaf) and Zingiber officinales (rhizome) after 15 minutes of incubation respectively. PMID:24049501

Imtiaj, Ahmed; Rahman, Syed Ajijur; Alam, Shahidul; Parvin, Rehana; Farhana, Khandaker Mursheda; Kim, Sang-Beom

2005-01-01

140

Separate Proliferation Kinetics of Fibroblast Growth Factor Responsive and Epidermal Growth FactorResponsive Neural Stem Cells within the Embryonic Forebrain Germinal Zone  

Microsoft Academic Search

The embryonic forebrain germinal zone contains two separate and additive populations of epidermal growth factor (EGF)- and fibroblast growth factor (FGF)-responsive stem cells that both exhibit self-renewal and multipotentiality. Although cumulative S phase labeling studies have investigated the proliferation kinetics of the overall population of precursor cells within the forebrain germinal zone through brain development, little is known about when

David J. Martens; Vincent Tropepe; Derek van der Kooy

2000-01-01

141

One-Carbon Metabolism in Plants. Regulation of Tetrahydrofolate Synthesis during Germination and Seedling Development  

PubMed Central

Tetrahydrofolate (THF) is a central cofactor for one-carbon transfer reactions in all living organisms. In this study, we analyzed the expression of dihydropterin pyrophosphokinase-dihydropteroate synthase (HPPK-DHPS) in pea (Pisum sativum) organs during development, and so the capacity to synthesize dihydropteroate, an intermediate in the de novo THF biosynthetic pathway. During seedling development, all of the examined organs/tissues contain THF coenzymes, collectively termed folate, and express the HPPK-DHPS enzyme. This suggests that each organ/tissue is autonomous for the synthesis of THF. During germination, folate accumulates in cotyledons and embryos, but high amounts of HPPK-DHPS are only observed in embryos. During organ differentiation, folate is synthesized preferentially in highly dividing tissues and in photosynthetic leaves. This is associated with high levels of the HPPK-DHPS mRNA and protein, and a pool of folate 3- to 5-fold higher than in the rest of the plant. In germinating embryos and in meristematic tissues, the high capacity to synthesize and accumulate folate correlates with the general resumption of cell metabolism and the high requirement for nucleotide synthesis, major cellular processes involving folate coenzymes. The particular status of folate synthesis in leaves is related to light. Thus, when illuminated, etiolated leaves gradually accumulate the HPPK-DHPS enzyme and folate. This suggests that folate synthesis plays an important role in the transition from heterotrophic to photoautotrophic growth. Analysis of the intracellular distribution of folate in green and etiolated leaves indicates that the coenzymes accumulate mainly in the cytosol, where they can supply the high demand for methyl groups. PMID:12644692

Jabrin, Samuel; Ravanel, Stphane; Gambonnet, Bernadette; Douce, Roland; Rbeill, Fabrice

2003-01-01

142

One-carbon metabolism in plants. Regulation of tetrahydrofolate synthesis during germination and seedling development.  

PubMed

Tetrahydrofolate (THF) is a central cofactor for one-carbon transfer reactions in all living organisms. In this study, we analyzed the expression of dihydropterin pyrophosphokinase-dihydropteroate synthase (HPPK-DHPS) in pea (Pisum sativum) organs during development, and so the capacity to synthesize dihydropteroate, an intermediate in the de novo THF biosynthetic pathway. During seedling development, all of the examined organs/tissues contain THF coenzymes, collectively termed folate, and express the HPPK-DHPS enzyme. This suggests that each organ/tissue is autonomous for the synthesis of THF. During germination, folate accumulates in cotyledons and embryos, but high amounts of HPPK-DHPS are only observed in embryos. During organ differentiation, folate is synthesized preferentially in highly dividing tissues and in photosynthetic leaves. This is associated with high levels of the HPPK-DHPS mRNA and protein, and a pool of folate 3- to 5-fold higher than in the rest of the plant. In germinating embryos and in meristematic tissues, the high capacity to synthesize and accumulate folate correlates with the general resumption of cell metabolism and the high requirement for nucleotide synthesis, major cellular processes involving folate coenzymes. The particular status of folate synthesis in leaves is related to light. Thus, when illuminated, etiolated leaves gradually accumulate the HPPK-DHPS enzyme and folate. This suggests that folate synthesis plays an important role in the transition from heterotrophic to photoautotrophic growth. Analysis of the intracellular distribution of folate in green and etiolated leaves indicates that the coenzymes accumulate mainly in the cytosol, where they can supply the high demand for methyl groups. PMID:12644692

Jabrin, Samuel; Ravanel, Stphane; Gambonnet, Bernadette; Douce, Roland; Rbeill, Fabrice

2003-03-01

143

Arabidopsis Fatty Acid Desaturase FAD2 Is Required for Salt Tolerance during Seed Germination and Early Seedling Growth  

PubMed Central

Fatty acid desaturases play important role in plant responses to abiotic stresses. However, their exact function in plant resistance to salt stress is unknown. In this work, we provide the evidence that FAD2, an endoplasmic reticulum localized ?-6 desaturase, is required for salt tolerance in Arabidopsis. Using vacuolar and plasma membrane vesicles prepared from the leaves of wild-type (Col-0) and the loss-of-function Arabidopsis mutant, fad2, which lacks the functional FAD2, we examined the fatty acid composition and Na+-dependent H+ movements of the isolated vesicles. We observed that, when compared to Col-0, the level of vacuolar and plasma membrane polyunsaturation was lower, and the Na+/H+ exchange activity was reduced in vacuolar and plasma membrane vesicles isolated from fad2 mutant. Consistent with the reduced Na+/H+ exchange activity, fad2 accumulated more Na+ in the cytoplasm of root cells, and was more sensitive to salt stress during seed germination and early seedling growth, as indicated by CoroNa-Green staining, net Na+ efflux and salt tolerance analyses. Our results suggest that FAD2 mediated high-level vacuolar and plasma membrane fatty acid desaturation is essential for the proper function of membrane attached Na+/H+ exchangers, and thereby to maintain a low cytosolic Na+ concentration for salt tolerance during seed germination and early seedling growth in Arabidopsis. PMID:22279586

Sun, Jian; Li, Bei; Zhu, Qiang; Chen, Shaoliang; Zhang, Hongxia

2012-01-01

144

Soil warming increases plant species richness but decreases germination from the alpine soil seed bank.  

PubMed

Global warming is occurring more rapidly above the treeline than at lower elevations and alpine areas are predicted to experience above average warming in the future. Temperature is a primary factor in stimulating seed germination and regulating changes in seed dormancy status. Thus, plant regeneration from seed will be crucial to the persistence, migration and post disturbance recruitment of alpine plants in future climates. Here, we present the first assessment of the impact of soil warming on germination from the persistent alpine soil seed bank. Contrary to expectations, soil warming lead to reduced overall germination from the soil seed bank. However, germination response to soil temperature was species specific such that total species richness actually increased by nine with soil warming. We further explored the system by assessing the prevalence of seed dormancy and germination response to soil disturbance, the frequency of which is predicted to increase under climate change. Seeds of a significant proportion of species demonstrated physiological dormancy mechanisms and germination of several species appeared to be intrinsically linked to soil disturbance. In addition, we found no evidence of subalpine species and little evidence of exotic weed species in the soil, suggesting that the soil seed bank will not facilitate their invasion of the alpine zone. In conclusion, changes in recruitment via the alpine soil seed bank can be expected under climate change, as a result of altered dormancy alleviation and germination cues. Furthermore, the alpine soil seed bank, and the species richness therein, has the potential to help maintain local species diversity, support species range shift and moderate species dominance. Implications for alpine management and areas for further study are also discussed. PMID:23505066

Hoyle, Gemma L; Venn, Susanna E; Steadman, Kathryn J; Good, Roger B; McAuliffe, Edward J; Williams, Emlyn R; Nicotra, Adrienne B

2013-05-01

145

Effect of seed depth on germination and growth of velvetleaf (Abutilon theophrasti Medic.).  

PubMed

Importance of several weed species has been considerably increased during the last few decades in Hungary. Velvetleaf (Abutilon theophrasti Medic.) belongs to this spreading weed group as well. This weed species was in the 27th position in the course of the fourth Hungarian weed survey, but at the time of the fifth weed survey in 2007-2008 it stepped forward to the 10th position in the cornfields of Zala County. Requiring a warm climate, global climate warming plays a significant role in its rapid spread. Moreover, its effective reproduction strategy supports its occurrence and continuous spread in almost all field crops. Protection against velvetleaf can only be successful, if we know its biological and ecological characteristics. Comprehensive knowledge of the plant and selection of a proper application of weed control methods together can result velvetleaf free crop fields. The experiment was set up on the 29th of April 2009 at Keszthely where fifty seeds were sown into 50 litres volume plastic pots, in four replications with fifty pieces of seed per each plot. Germination percent of velvetleaf seeds and several growth indexes of seedlings (stem- and root length, leaf area, number of leaves, stem- and root fresh and dry weight) were measured on three different sampling dates. PMID:21542475

Nagy, V; Ndasy, E; Lehoczky, E

2010-01-01

146

Growth of plant culture.  

PubMed

A series of articles by Nick Battey published throughout 2003 has been challenging plant scientists to embrace plant culture. Fine art, literature, mythology, plant lore, religion, philosophy and plant science all contribute to plant culture and Battey believes that it is up to us, the scientists, to stimulate greater appreciation of our work by striving for a richer culture. PMID:14659704

Napier, Richard

2003-12-01

147

Comparison of antagonisms between abscisic acid and various growth stimulators during germination of barley and radish seeds  

Microsoft Academic Search

In this work, antagonism among abscisic acid preventing seedling growth and germination of barley and radish seeds and gibberellic acid, kinetin, benzyladenine, ethylene, brassinosteroid, triacontanol and polyamines (cadaverine, putrescine, spermidine, spermine) was studied. Although many stimulators mentioned were not able to overcome the radicle elongation- preventive effect of abscisic acid, the seeds reached 100% germination in this hormone medium. In

Kursat Cavusoglu; Kudret Kabar

2007-01-01

148

In Vivo Cell Wall Loosening by Hydroxyl Radicals during Cress Seed Germination and Elongation Growth1[W][OA  

E-print Network

, including seed germination, elongation growth, and fruit ripening. Here, we report direct in vivo evidence weakening and radicle elongation and were inhibited by the germination-inhibiting hormone abscisic acid. Both effects were reversed by gibberellin. Distinct and tissue-specific target sites of ?OH attack

Leubner, Gerhard

149

Use of Hydrogen Peroxide to Disinfect Hydroponic Plant Growth Systems  

NASA Technical Reports Server (NTRS)

Hydrogen peroxide was studied as an alternative to conventional bleach and rinsing methods to disinfect hydroponic plant growth systems. A concentration of 0.5% hydrogen peroxide was found to be effective. Residual hydrogen peroxide can be removed from the system by repeated rinsing or by flowing the solution through a platinum on aluminum catalyst. Microbial populations were reduced to near zero immediately after treatment but returned to pre-disinfection levels 2 days after treatment. Treating nutrient solution with hydrogen peroxide and planting directly into trays being watered with the nutrient solution without replenishment, was found to be detrimental to lettuce germination and growth.

Barta, Daniel J.; Henderson, Keith

2000-01-01

150

Seed Germination and Reproductive Features of Lysimachia minoricensis (Primulaceae), a Wild?extinct Plant  

PubMed Central

Lysimachia minoricensis is one of the few Mediterranean endemic plants (Minorca, Balearic islands) that has gone extinct in the wild but which persists as extant germplasm or cultivated plants in several botanical gardens. Reproductive features (seed set, number of seeds per capsule, seed weight) and germination responses to constant temperatures, sea water and dry?heat pre?treatments were investigated to determine the extent to which they may have influenced the extinction of the species. Seed set in Lysimachia is not dependent on pollinators, suggesting a functional selfer breeding system. Most plants produced a large mean number of fruits (232) and seeds (466), and the mean production of seeds per individual was estimated to be almost 1100. Overall, no highly specific requirements were observed for seed germination. Seed germination was not inhibited in the dark, and a high germinability (over 87 % in all cases) was recorded in most experiments, with the exception of those performed at low temperatures (5 and 10 C). These data suggest that fertility and seed viability were not the major causes of extinction. The high reproductive performance of L. minoricensis is in striking contrast to its status as a wild?extinct plant, suggesting that extrinsic factors were responsible for its extinction. PMID:12099529

ROSSELL, JOSEP A.; MAYOL, MARIA

2002-01-01

151

Germination and Seedling Growth of Perennial Ryegrass in Acid Sulfate Soil Treated by Pyrite Nano-Encapsulation  

NASA Astrophysics Data System (ADS)

The trial pot experiment was conducted to validate the effect of encapsulation in reduction of acid rock drainage. Six different treatments were performed: A = control, four times spraying of distilled water; B = four times of 0.01 M H2O2; C = once-encapsulated and three times spraying of distilled water; D = twice-encapsulated and twice spraying of distilled water; E = three times-encapsulated and once spraying of distilled water and F = four times-encapsulated for the acid sulfate soil with pyrite bearing andesite powder and sand. After the encapsulation treatment, the perennial ryegrass (Loium perenne) was sowed to evaluate germination rate and growth for three months. The leachate was examined for the chemical properties. The leachate from the A pot (control) is characterized as acidic (pH below 3) and high concentrations of SO4-2: 12,022 mg/L, Al: 85.8 mg/L and Mn: 34.1 mg/L which can be toxic effect to the plant growth. However, the leachate from encapsulated pots showed near neutral (pH 6 to 7) and low concentrations of SO4-2 (below 3,000 mg/L), Al (below 45mg/L) and Mn (24 gm/L). The frequency of encapsulation treatment is related to reduction of acidic drainage. It was hard to identify the significant difference of the seed germination rate of ryegrass between the treatments, although root and shoot growth showed three times difference between the control (1.90g/pot) and four times encapsulated treatment (6.33g/pot) after 2 month growth. It is suggested that encapsulation of pyrite in acid sulfate soil causes the reduction of acidic drainage resulting in the higher growth of herbaceous plants.

Lee, J.; Kim, J.; Yi, J.; Kim, T.

2007-05-01

152

Growth and germination of proteolytic Clostridium botulinum in vegetable-based media.  

PubMed

The growth of proteolytic Clostridium botulinum from spore inocula and changes in spore counts in mushroom, broccoli, and potato pures were monitored. Four strains of proteolytic C. botulinum types A and B were inoculated separately at approximately 10(4) spores per ml in nutrient broth and vegetable pures incubated at 15, 20, and 30 degrees C for up to 52 days. The times for the cell populations to increase 1,000-fold (T1,000) in the tested vegetables (1 to 5 days at 30 degrees C, 3 to 16 days at 20 degrees C, 7 to > 52 days at 15 degrees C) were similar to those for meat or fish. Only temperature significantly influenced growth rate. In contrast, the lag phase depended on the strains and media tested, in addition to temperature. Lag times and T1,000S for proteolytic C. botulinum were longer for potato and broccoli pures than for mushroom pure. These differences were not related to different pHs or redox potentials. The germination level, evaluated as the decrease in the spore count, was low. The addition of a germinant mixture (L-cysteine, L-alanine, and sodium lactate) to some strains inoculated in vegetable pures resulted in an increase in germination, suggesting a lack of germination-triggering agents in the vegetable pures. PMID:12747693

Braconnier, Agns; Broussolle, Vronique; Dargaignaratz, Claire; Nguyen-The, Christophe; Carlin, Frdric

2003-05-01

153

Water potential and ionic effects on germination and seedling growth of two cold desert shrubs.  

PubMed

We tested expectations that two desert shrubs would differ in germination and seedling relative growth rate (RGR) responses to Na and ?(s) stress. The study species, Chrysothamnus nauseosus ssp. consimilis and Sarcobatus vermiculatus (hereafter referred to by genus), differ in their distribution along salinity gradients, with Chrysothamnus inhabiting only less saline areas. In growth chamber studies, declining ?(s) (-0.82 to -2.71 MPa) inhibited germination of both species, and Chrysothamnus was less tolerant of ?(s) stress than Sarcobatus. Germination fell below 10% for Chrysothamnus at -1.64 MPa (NaCl and PEG), and for Sarcobatus at -2.4 MPa PEG. Neither species exhibited ion toxicity. There was substantial ion enhancement for Sarcobatus in lower ?(s), allowing for 40% germination in -2.71 MPa NaCl. For seedling RGR, species were not different at -0.29 or -0.82 MPa (0 and 100 mmol/L NaCl, respectively), but Chrysothamnus RGR declined substantially at -1.3 MPa (200 mmol/L NaCl). The greater stress tolerance of Sarcobatus was not associated with a lower RGR under nonsaline conditions. Species differences in seed and seedling ?(s) stress tolerance probably contribute to the restricted distribution of Chrysothamnus to less saline areas. The Na uptake of Sarcobatus seedlings enhances its ability to deal with declining ?(s) and establish in more saline areas. PMID:10449394

Dodd, G L; Donovan, L A

1999-08-01

154

Chemical Control of Plant Growth.  

ERIC Educational Resources Information Center

Seven experiments are presented in this Science Study Aid to help students investigate the control of plant growth with chemicals. Plant growth regulators, weed control, and chemical pruning are the topics studied in the experiments which are based on investigations that have been and are being conducted at the U. S. Agricultural Research Center,

Agricultural Research Center (USDA), Beltsville, MD.

155

Phytochrome, plant growth and flowering  

NASA Technical Reports Server (NTRS)

Attempts to use artificially lit cabinets to grow plants identical to those growing in sunlight have provided compelling evidence of the importance of light quality for plant growth. Changing the balance of red (R) to far-red (FR) radiation, but with a fixed photosynthetic input can shift the phytochrome photoequilibrium in a plant and generate large differences in plant growth. With FR enrichment the plants elongate, and may produce more leaf area and dry matter. Similar morphogenic responses are also obtained when light quality is altered only briefly (15-30 min) at the end-of-the-day. Conversely, for plants grown in natural conditions the response of plant form to selective spectral filtering has again shown that red and far-red wavebands are important as found by Kasperbauer and coworkers. Also, where photosynthetic photon flux densities (PPFD) of sunlight have been held constant, the removal of far-red alone alters plant growth. With FR depletion plants grown in sunlight are small, more branched and darker green. Here we examine the implications for plant growth and flowering when the far-red composition of incident radiation in plant growth chambers is manipulated.

King, R. W.; Bagnall, D. J.

1994-01-01

156

Plant growth-promoting rhizobacteria  

Microsoft Academic Search

Plant growth-promoting rhizobacteria (PGPR) are a group of free-living bacteria that colonize the rhizosphere and benefit\\u000a the root growth. Bacteria of diverse genera were identified as PGPR of which Bacillus and Pseudomonas spp. are predominant. PGPR exert a direct effect on plant growth by production of phytohormones, solubilization of inorganic\\u000a phosphates, increased iron nutrition through iron-chelating siderophores and volatile compounds

Appa Podile; G. Kishore

157

Climate warming could shift the timing of seed germination in alpine plants  

PubMed Central

Background and Aims Despite the considerable number of studies on the impacts of climate change on alpine plants, there have been few attempts to investigate its effect on regeneration. Recruitment from seeds is a key event in the life-history of plants, affecting their spread and evolution and seasonal changes in climate will inevitably affect recruitment success. Here, an investigation was made of how climate change will affect the timing and the level of germination in eight alpine species of the glacier foreland. Methods Using a novel approach which considered the altitudinal variation of temperature as a surrogate for future climate scenarios, seeds were exposed to 12 different cycles of simulated seasonal temperatures in the laboratory, derived from measurements at the soil surface at the study site. Key Results Under present climatic conditions, germination occurred in spring, in all but one species, after seeds had experienced autumn and winter seasons. However, autumn warming resulted in a significant increase in germination in all but two species. In contrast, seed germination was less sensitive to changes in spring and/or winter temperatures, which affected only three species. Conclusions Climate warming will lead to a shift from spring to autumn emergence but the extent of this change across species will be driven by seed dormancy status. Ungerminated seeds at the end of autumn will be exposed to shorter winter seasons and lower spring temperatures in a future, warmer climate, but these changes will only have a minor impact on germination. The extent to which climate change will be detrimental to regeneration from seed is less likely to be due to a significant negative effect on germination per se, but rather to seedling emergence in seasons that the species are not adapted to experience. Emergence in autumn could have major implications for species currently adapted to emerge in spring. PMID:22596094

Mondoni, Andrea; Rossi, Graziano; Orsenigo, Simone; Probert, Robin J.

2012-01-01

158

Flooding and Plant Growth  

PubMed Central

This Special Issue is based on the 7th Conference of the International Society for Plant Anaerobiosis (ISPA), held in Nijmegen, The Netherlands, 1216 June 2001. The papers describe and analyse many of the responses that plants display when subjected to waterlogging of the soil or deeper submergence. These responses may be injurious or adaptive, and are discussed at various levels of organizational complexity ranging from ecosystem processes, through individual plants to single cells. The research incorporates molecular biology and genetics, cell physiology, biochemistry, hormone physiology, whole plant physiology, plant demography and ecology. The study of the damage to young rice plants caused by submergence, especially as experienced in the rainfed lowlands of Asia, is comprehensively addressed. This work integrates various specialized approaches ranging from agronomy to molecular genetics, and demonstrates how plant biology can be harnessed to improve stress tolerance in an important crop species while simultaneously improving basic understanding of tolerance mechanisms and plant processes.

VISSER, E. J. W.; VOESENEK, L. A. C. J.; VARTAPETIAN, B. B.; JACKSON, M. B.

2003-01-01

159

EFFECTS OF LITTER ON AQUATIC MACROPHYTE GERMINATION AND GROWTH  

Microsoft Academic Search

In Arkansas, during seasonal drought periods, lake water levels drop leaving exposed mudflats which are primary sites for seedling establishment. Commonly, these exposed mudflats are partially covered with decomposing litter from previous stands of aquatic plants. In this study, aqueous leachates from the litter of four macrophytes, Eleocharis quadrangulata, Justicia americana, Polygonum lapathifolium, and Potamogeton nodosus, were used to test

JAMES B. GRACE

1985-01-01

160

ALLELOPATHIC EFFECTS OF FIVE SELECTED WEED SPECIES ON SEED GERMINATION AND SEEDLING GROWTH OF CORN  

Microsoft Academic Search

Samad M. A., Rahman M. M., Hossain A. K. M. M., Rahman M. S. and Rahman S. M. 2008. Allelopathic Effects of Five Selected Weed Species on Seed Germination and Seedling Growth of Corn. J.Soil .Nature. 2(2): 13-18 An investigation was carried out in typical maize growing sandy loam soil at the Agronomy Laboratory. Bangladesh Agricultural University, Mymensingh during March

M. A. SAMAD; M. M. RAHMAN; M. S. RAHMAN; S. M. RAHMAN

161

Salinity Induced Changes in ?-Amylase Activity During Germination and Early Cotton Seedling Growth  

Microsoft Academic Search

Salinity induced changes in a-amylase activity in three cotton cultivars (NIAB-Karishma, NIAB-86 and K-115) was studied during germination and early seedling growth under controlled conditions. The increase in NaCl concentration resulted in the decrease in a-amylase activity and break down of starch into reducing and non-reducing sugars in all cultivars, however, it was more pronounced in NIAB-86. K-115 showed highest

M. Y. Ashraf; G. Sarwar; R. Afaf; A. Sattar

2002-01-01

162

Effects of temperature on urediniospore germination, germ tube growth, and initiation of infection in soybean by phakopsora isolates.  

PubMed

ABSTRACT Temperature is a critical factor in plant disease development. As part of a research program to determine how specific environmental variables affect soybean rust, we determined temperature effects on urediniospore germination and germ tube growth of four isolates of Phakopsora pachyrhizi, one each from Brazil, Hawaii, Taiwan, and Zimbabwe, and an isolate of P. meibomiae from Puerto Rico, collected over a 25-year period. Also compared were the effects of temperature during a night dew period on initiation of disease by the P. pachyrhizi isolates. All variables were fit to a nonlinear beta function with temperature as the independent variable. Minimum, maximum, and optimum temperatures, along with shape parameters of the beta function for each variable, were statistically analyzed. All Phakopsora isolates behaved similarly as to how temperature affected urediniospore germination, germ tube growth, and initiation of disease. The results suggest that P. pachyrhizi has changed little in the past few decades with respect to how it responds to temperature and that previously collected research data continues to be valid, simplifying the development of soybean rust disease models. PMID:18943640

Bonde, M R; Berner, D K; Nester, S E; Frederick, R D

2007-08-01

163

Assessment of chromium efficacy on germination, root elongation, and coleoptile growth of wheat (Triticum aestivum L.) at different growth periods.  

PubMed

The tannery effluents contain a high concentration of chromium (Cr). It drastically reduces the crop yield when used for irrigation purpose. A huge volume of tannery effluents is available as irrigation for crop production. It is negatively affecting germination as well as yield of the crop. The wheat seeds were exposed to five different concentrations of Cr (0, 20, 40, 80, and 100 ppm). In Petri plates, 100 seeds were placed and the germination percent was recorded after 72 hour (h). Root elongation and coleoptile growth were measured at 72, 120, 168, and 240 h. Results showed that the germination percent of the test crop decreased with increasing Cr levels. It decreased by 6, 14, 30, and 37 % under the Cr concentration of 20, 40, 80, and 100 ppm, respectively. The root elongation was more sensitive than the coleoptile growth. The negative correlation was found between Cr levels and root elongation as well as coleoptile growth. These growth parameters were significantly affected up to 80 ppm of Cr level. The wheat growers using tannery effluent as irrigation should be well treated prior to application. PMID:24415062

Dotaniya, M L; Das, H; Meena, V D

2014-05-01

164

Azospirillum plant growth-promoting strains are nonpathogenic on tomato, pepper, cotton, and wheat  

Microsoft Academic Search

Six strains of Azospirillum belonging to five species of plant growth-promoting bacteria (A. brasilense, A. lipoferum, A. amazonense, A. irakense, and A. halopraeference) did not cause visible disease symptoms on the roots or leaves of tomato, pepper, cotton, and wheat, failed to inhibit seed germination, and did not reduce plant dry weight when seven standard techniques for the inoculation of

Yoav Bashan

1998-01-01

165

Wyoming Big Sagebrush (Artemisia tridentata ssp. wyomingensis) Seedling Growth and Maternal Plant Stand Position  

Microsoft Academic Search

Little is known of maternal plant influence upon seed- ling characteristics of native shrubs. This study examined influence of maternal Wyoming big sagebrush (Artemisia tridentata ssp. wyomingensis) stand position on emergence and growth of seed- lings. Seedlings from maternal plants in upslope, core, and downslope positions were grown in a common greenhouse setting. Percent germination, height, and canopy volume of

A. L. Hild; B. Christensen; A. Maier

1999-01-01

166

Ecotoxicological effects of polycyclic musks and cadmium on seed germination and seedling growth of wheat ( Triticum aestivum)  

Microsoft Academic Search

Single and joint toxic effects of polycyclic musks including 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta[g]-2-benzopyran (HHCB) and 7-acetyl-1,1,3,4,4,6-hexamethyl-1,2,3,4-tetrahydronapthalene (AHTN) and cadmium (Cd) on seed germination and seedling growth of wheat (Triticum aestivum) were investigated. The results showed that the toxicity sequence of HHCB toxic to wheat seed germination and seedling growth was similar to that of AHTN, that is, germination rate > shoot elongation >

Cuihong Chen; Qixing Zhou; Yanyu Bao; Yaning Li; Ping Wang

2010-01-01

167

The Annual Growth In Plants  

E-print Network

KU ScholarWorks | The University of Kansas Pre-1923 Dissertations and Theses Collection The Annual Growth In Plants 1903 by J. E. Courtright This work was digitized by the Scholarly Communications program staff in the KU Libraries Center...

Courtright, J. E.

1903-01-01

168

Plant Growth Puzzle  

NSDL National Science Digital Library

This analysis and discussion activity presents a structured sequence of questions to challenge students to explain why a plant that sprouts and grows in the light weighs more than the seed it came from, whereas a plant that sprouts and grows in the dark weighs less than the seed it came from.

Waldron, Ingrid

169

[Effects of sand burying on caryopsis germination and seedling growth of Bromus inermis Leyss].  

PubMed

This paper studied the effects of different depth sand burying on the caryopsis germination, seedling emergence and growth of Bromus inermis Leyss., a perennial gramineous grass dominated on Othidag sandy land. The results showed that the maximum burying depth for B. inermis caryopsis germination and seedling emergence was 12 cm and 8 cm, respectively. Below the thresholds, the percentages of caryopsis germination and seedling emergence decreased with increasing depth of sand burying. All the 1- and 2-week-old seedlings of B. inermis could survive when the sand burying depth was up to 33% of their height, and their biomass was no less than the unburied seedlings. When the burying depth increased to 66% of their height, 70% of 1-week-old seedlings and 25% of 2-week-old seedlings could survive, but their growth was impaired. No seedlings could survive when they were wholly buried in sand. When buried by sand, the seedlings allocated more biomass for the development of their aboveground part, which might be an important adaptation strategy of B. inermis to sand burying. PMID:18260444

Yang, Hui-ling; Cao, Zhi-ping; Dong, Ming; Ye, Yong-zhong; Huang, Zhen-ying

2007-11-01

170

Inhibition of Orobanche crenata seed germination and radicle growth by allelochemicals identified in cereals.  

PubMed

Orobanche crenata is a parasitic weed that causes severe yield losses in important grain and forage legume crops. Cereals have been reported to inhibit O. crenata parasitism when grown intercropped with susceptible legumes, but the responsible metabolites have not been identified. A number of metabolites have been reported in cereals that have allelopathic properties against weeds, pests, and pathogens. We tested the effect of several allelochemicals identified in cereals on O. crenata seed germination and radicle development. We found that 2-benzoxazolinone, its derivative 6-chloroacetyl-2-benzoxazolinone, and scopoletin significantly inhibited O. crenata seed germination. Benzoxazolinones, l-tryptophan, and coumalic acid caused the stronger inhibition of radicle growth. Also, other metabolites reduced radicle length, this inhibition being dose-dependent. Only scopoletin caused cell necrotic-like darkening in the young radicles. Prospects for their application to parasitic weed management are discussed. PMID:24044614

Fernndez-Aparicio, Mnica; Cimmino, Alessio; Evidente, Antonio; Rubiales, Diego

2013-10-16

171

Phytochrome, Plant Growth and Flowering.  

National Technical Information Service (NTIS)

Attempts to use artificially lit cabinets to grow plants identical to those growing in sunlight have provided compelling evidence of the importance of light quality for plant growth. Changing the balance of red (R) to far-red (FR) radiation, but with a fi...

R. W. King, D. J. Bagnall

1994-01-01

172

Phospholipids as Plant Growth Regulators  

Microsoft Academic Search

In this paper the potential to use phospholipids and lysophospholipids as plant growth regulators is discussed. Recent evidence shows that phospholipids and phospholipases play an\\u000a important signalling role in the normal course of plant development and in the response of plants to abiotic and biotic stress.\\u000a It is apparent that phospholipase A (PLA), C (PLC) and D (PLD), lysophospholipids, and

A. Keith Cowan

2006-01-01

173

Paternal effects on seed germination: a barrier to the genetic assimilation of an endemic plant taxon?  

PubMed

We used a crossing experiment to investigate post-zygotic barriers that might limit introgression between a pair of closely-related, gynodioecious plant species--the widespread weed Silene vulgaris and the local Swedish endemic S. uniflora ssp. petraea. The study not only considered the effects of hybridization on conventionally-used (primary) fitness components such as seed set and progeny survival, but also provided a test for the effects of interspecific hybridization on characters with more subtle or habitat-specific effects on fitness. We detected highly significant paternal effects on seed germination properties, with the germination characteristics of hybrid seed resembling those of the species that served as the pollen donor. These paternal effects on germination represent a potentially strong barrier to interspecific introgression in the two species' natural habitats, where an inappropriate germination response in the habitat of the maternal parent may lead to the failure of seedling establishment. Interspecific crosses had weak or variable effects on progeny survival, flowering and sex ratio, but these effects could not be interpreted in terms of barriers to introgression. Our results indicate that nuclear restorers in S. vulgaris have the capacity to suppress cytoplasmic male-sterility genes in its endemic congener. PMID:18544070

Andersson, S; Mnsby, E; Prentice, H C

2008-09-01

174

SEC8, a Subunit of the Putative Arabidopsis Exocyst Complex, Facilitates Pollen Germination and Competitive Pollen Tube Growth1[w  

PubMed Central

The exocyst, a complex of eight proteins, contributes to the morphogenesis of polarized cells in a broad range of eukaryotes. In these organisms, the exocyst appears to facilitate vesicle docking at the plasma membrane during exocytosis. Although we had identified orthologs for each of the eight exocyst components in Arabidopsis (Arabidopsis thaliana), no function has been demonstrated for any of them in plants. The gene encoding one exocyst component ortholog, AtSEC8, is expressed in pollen and vegetative tissues of Arabidopsis. Genetic studies utilizing an allelic series of six independent T-DNA mutations reveal a role for SEC8 in male gametophyte function. Three T-DNA insertions in SEC8 cause an absolute, male-specific transmission defect that can be complemented by expression of SEC8 from the LAT52 pollen promoter. Microscopic analysis shows no obvious abnormalities in the microgametogenesis of the SEC8 mutants, and the mutant pollen grains appear to respond to the signals that initiate germination. However, in vivo assays indicate that these mutant pollen grains are unable to germinate a pollen tube. The other three T-DNA insertions are associated with a partial transmission defect, such that the mutant allele is transmitted through the pollen at a reduced frequency. The partial transmission defect is only evident when mutant gametophytes must compete with wild-type gametophytes, and arises in part from a reduced pollen tube growth rate. These data support the hypothesis that one function of the putative plant exocyst is to facilitate the initiation and maintenance of the polarized growth of pollen tubes. PMID:16040664

Cole, Rex A.; Synek, Lukas; Zarsky, Viktor; Fowler, John E.

2005-01-01

175

SEC8, a subunit of the putative Arabidopsis exocyst complex, facilitates pollen germination and competitive pollen tube growth.  

PubMed

The exocyst, a complex of eight proteins, contributes to the morphogenesis of polarized cells in a broad range of eukaryotes. In these organisms, the exocyst appears to facilitate vesicle docking at the plasma membrane during exocytosis. Although we had identified orthologs for each of the eight exocyst components in Arabidopsis (Arabidopsis thaliana), no function has been demonstrated for any of them in plants. The gene encoding one exocyst component ortholog, AtSEC8, is expressed in pollen and vegetative tissues of Arabidopsis. Genetic studies utilizing an allelic series of six independent T-DNA mutations reveal a role for SEC8 in male gametophyte function. Three T-DNA insertions in SEC8 cause an absolute, male-specific transmission defect that can be complemented by expression of SEC8 from the LAT52 pollen promoter. Microscopic analysis shows no obvious abnormalities in the microgametogenesis of the SEC8 mutants, and the mutant pollen grains appear to respond to the signals that initiate germination. However, in vivo assays indicate that these mutant pollen grains are unable to germinate a pollen tube. The other three T-DNA insertions are associated with a partial transmission defect, such that the mutant allele is transmitted through the pollen at a reduced frequency. The partial transmission defect is only evident when mutant gametophytes must compete with wild-type gametophytes, and arises in part from a reduced pollen tube growth rate. These data support the hypothesis that one function of the putative plant exocyst is to facilitate the initiation and maintenance of the polarized growth of pollen tubes. PMID:16040664

Cole, Rex A; Synek, Luks; Zarsky, Viktor; Fowler, John E

2005-08-01

176

A Dynamic, Architectural Plant Model Simulating Resource?dependent Growth  

PubMed Central

Background and Aims Physiological and architectural plant models have originally been developed for different purposes and therefore have little in common, thus making combined applications difficult. There is, however, an increasing demand for crop models that simulate the genetic and resource?dependent variability of plant geometry and architecture, because man is increasingly able to transform plant production systems through combined genetic and environmental engineering. Model GREENLAB is presented, a mathematical plant model that simulates interactions between plant structure and function. Dual?scale automaton is used to simulate plant organogenesis from germination to maturity on the basis of organogenetic growth cycles that have constant thermal time. Plant fresh biomass production is computed from transpiration, assuming transpiration efficiency to be constant and atmospheric demand to be the driving force, under non?limiting water supply. The fresh biomass is then distributed among expanding organs according to their relative demand. Demand for organ growth is estimated from allometric relationships (e.g. leaf surface to weight ratios) and kinetics of potential growth rate for each organ type. These are obtained through parameter optimization against empirical, morphological data sets by running the model in inverted mode. Potential growth rates are then used as estimates of relative sink strength in the model. These and other hidden plant parameters are calibrated using the non?linear, least?square method. Key Results and Conclusions The model reproduced accurately the dynamics of plant growth, architecture and geometry of various annual and woody plants, enabling 3D visualization. It was also able to simulate the variability of leaf size on the plant and compensatory growth following pruning, as a result of internal competition for resources. The potential of the models underlying concepts to predict the plants phenotypic plasticity is discussed. PMID:15056562

YAN, HONG?PING; KANG, MENG ZHEN; DE REFFYE, PHILIPPE; DINGKUHN, MICHAEL

2004-01-01

177

Germination and early plant development of 10 plant species exposed to Nano TiO2 and CeO2  

EPA Science Inventory

Ten agronomic plant species were exposed to different concentrations of nano-TiO2 or CeO2 (0, 250, 500 and 1000 ug/l) and followed to examine effects on germination and early seedling development. For TiO2, cabbage showed increased and corn decreased percent germination, while ...

178

Whole-Plant Growth Stage Ontology for Angiosperms and Its Application in Plant Biology1[OA  

PubMed Central

Plant growth stages are identified as distinct morphological landmarks in a continuous developmental process. The terms describing these developmental stages record the morphological appearance of the plant at a specific point in its life cycle. The widely differing morphology of plant species consequently gave rise to heterogeneous vocabularies describing growth and development. Each species or family specific community developed distinct terminologies for describing whole-plant growth stages. This semantic heterogeneity made it impossible to use growth stage description contained within plant biology databases to make meaningful computational comparisons. The Plant Ontology Consortium (http://www.plantontology.org) was founded to develop standard ontologies describing plant anatomical as well as growth and developmental stages that can be used for annotation of gene expression patterns and phenotypes of all flowering plants. In this article, we describe the development of a generic whole-plant growth stage ontology that describes the spatiotemporal stages of plant growth as a set of landmark events that progress from germination to senescence. This ontology represents a synthesis and integration of terms and concepts from a variety of species-specific vocabularies previously used for describing phenotypes and genomic information. It provides a common platform for annotating gene function and gene expression in relation to the developmental trajectory of a plant described at the organismal level. As proof of concept the Plant Ontology Consortium used the plant ontology growth stage ontology to annotate genes and phenotypes in plants with initial emphasis on those represented in The Arabidopsis Information Resource, Gramene database, and MaizeGDB. PMID:16905665

Pujar, Anuradha; Jaiswal, Pankaj; Kellogg, Elizabeth A.; Ilic, Katica; Vincent, Leszek; Avraham, Shulamit; Stevens, Peter; Zapata, Felipe; Reiser, Leonore; Rhee, Seung Y.; Sachs, Martin M.; Schaeffer, Mary; Stein, Lincoln; Ware, Doreen; McCouch, Susan

2006-01-01

179

Modeling plant growth and development Przemyslaw Prusinkiewicz  

E-print Network

Modeling plant growth and development Przemyslaw Prusinkiewicz Department of Computer Science of gene expression and the resulting plant form. Reference P. Prusinkiewicz: Modeling plant growth and development. Current Opinion in Plant Biology 7 (1), pp. 79-83. #12;Modeling plant growth and development

Prusinkiewicz, Przemyslaw

180

?-Aminobutyric acid (GABA) homeostasis regulates pollen germination and polarized growth in Picea wilsonii.  

PubMed

?-Aminobutyric acid (GABA) is a four-carbon non-protein amino acid found in a wide range of organisms. Recently, GABA accumulation has been shown to play a role in the stress response and cell growth in angiosperms. However, the effect of GABA deficiency on pollen tube development remains unclear. Here, we demonstrated that specific concentrations of exogenous GABA stimulated pollen tube growth in Picea wilsonii, while an overdose suppressed pollen tube elongation. The germination percentage of pollen grains and morphological variations in pollen tubes responded in a dose-dependent manner to treatment with 3-mercaptopropionic acid (3-MP), a glutamate decarboxylase inhibitor, while the inhibitory effects could be recovered in calcium-containing medium supplemented with GABA. Using immunofluorescence labeling, we found that the actin cables were disorganized in 3-MP treated cells, followed by the transition of endo/exocytosis activating sites from the apex to the whole tube shank. In addition, variations in the deposition of cell wall components were detected upon labeling with JIM5, JIM7, and aniline blue. Our results demonstrated that calcium-dependent GABA signaling regulates pollen germination and polarized tube growth in P. wilsonii by affecting actin filament patterns, vesicle trafficking, and the configuration and distribution of cell wall components. PMID:23900837

Ling, Yu; Chen, Tong; Jing, Yanping; Fan, Lusheng; Wan, Yinglang; Lin, Jinxing

2013-11-01

181

Preliminary studies on allelopatic effect of some woody plants on seed germination of rye-grass and tall fescue.  

PubMed

In order to investigation of allelopathic effects of some ornamental trees on seed germination of rye-grass (Lolium prenne) and tall fescue (Festuca arundinaceae), this experiment was conducted in a randomized complete block design with 3 replicates at the laboratory of Horticultural Sciences Department of Ferdowsi University of Mashhad, during 2008. In this research, we studied the effect of aqueous and hydro-alcoholic extracts of Afghanistan pine (Pinus eldarica), arizona cypress (Cupressus arizonica), black locust (Robinia psedue acacia) and box elder (Acer negundo) leaves that prepared in 1:5 ratio on seed germination percent and rate for two grasses. The results showed that all extracts decreased statistically seed germination in compared to control treatment. The highest germination percentage and germination rate of tested grass detected in control treatment. Hydro-alcoholic extracts of all woody plants (15, 30%) were completely inhibited seed germination of rye-grass and tall fescue. Also aqueous extract of arizona cypress was completely inhibited seed germination of tall fescue and had more inhibitory activity than other aqueous extracts on rye-grass. Between aqueous extracts, the highest and lowest seed germination of rye-grass was found in Afghanistan pine and arizona cypress, respectively. PMID:21313873

Arouiee, H; Nazdar, T; Mousavi, A

2010-11-01

182

Effect of Temperature, Light and Salinity on Seed Germination and Radicle Growth of the Geographically Widespread Halophyte Shrub Halocnemum strobilaceum  

PubMed Central

Background and Aims The small leafy succulent shrub Halocnemum strobilaceum occurs in saline habitats from northern Africa and Mediterranean Europe to western Asia, and it is a dominant species in salt deserts such as those of north-west China. The effects of temperature, light/darkness and NaCl salinity were tested on seed germination, and the effects of salinity were tested on seed germination recovery, radicle growth and radicle elongation recovery, using seeds from north-west China; the results were compared with those previously reported on this species from salt steppes in the Mediterranean region of Spain. Methods Seed germination was tested over a range of temperatures in light and in darkness and over a range of salinities at 25 C in the light. Seeds that did not germinate in the NaCl solutions were tested for germination in deionized water. Seeds from which radicles had barely emerged in deionized water were transferred to NaCl solutions for 10 d and then back to deionized water for 10 d to test for radicle growth and recovery. Key Results Seeds germinated to higher percentages in light than in darkness and at high than at low temperatures. Germination percentages decreased with an increase in salinity from 01 to 075 m NaCl. Seeds that did not germinate in NaCl solutions did so after transfer to deionized water. Radicle elongation was increased by low salinity, and then it decreased with an increase in salinity, being completely inhibited by ?20 m NaCl. Elongation of radicles from salt solutions <30 m resumed after seedlings were transferred to deionized water. Conclusions The seed and early seedling growth stages of the life cycle of H. strobilaceum are very salt tolerant, and their physiological responses differ somewhat between the Mediterranean salt steppe of Spain and the inland cold salt desert of north-west China. PMID:17428834

Qu, Xiao-Xia; Huang, Zhen-Ying; Baskin, Jerry M.; Baskin, Carol C.

2008-01-01

183

OsAP65, a rice aspartic protease, is essential for male fertility and plays a role in pollen germination and pollen tube growth.  

PubMed

Aspartic proteases (APs) comprise a large proteolytic enzyme family widely distributed in animals, microbes, viruses, and plants. The rice genome encodes 96 APs, of which only a few have been functionally characterized. Here, the identification and characterization of a novel AP gene, OsAP65, which plays an indispensable role in pollen tube growth in rice, is reported. The T-DNA insertion line of OsAP65 caused severe segregation distortion. In the progeny derived from an individual heterozygous for the T-DNA insertion, the wild type and T-DNA-carrying heterozygote segregated at a ratio close to 1:1, while homozygotes of disrupted OsAP65 (OsAP65-/-) were not recovered. Reciprocal crosses between heterozygotes and wild-type plants demonstrated that the mutant alleles could not be transmitted through the male gamete. Examination of the anthers from heterozygous plants revealed that the mutant pollen matured normally, but did not germinate or elongate. OsAP65 was expressed in various tissues and the transcript level in heterozygous plants was about half of the amount measured in the wild-type plants. The subcellular localization showed that OsAP65 is a pre-vacuolar compartment (PVC) protein. These results indicated that OsAP65 was essential for rice pollen germination and tube growth. PMID:23918968

Huang, Jianyan; Zhao, Xiaobo; Cheng, Ke; Jiang, Yunhe; Ouyang, Yidan; Xu, Caiguo; Li, Xianghua; Xiao, Jinghua; Zhang, Qifa

2013-08-01

184

The Strigolactone Germination Stimulants of the Plant-Parasitic Striga and Orobanche spp. Are Derived from the Carotenoid Pathway1  

PubMed Central

The seeds of parasitic plants of the genera Striga and Orobanche will only germinate after induction by a chemical signal exuded from the roots of their host. Up to now, several of these germination stimulants have been isolated and identified in the root exudates of a series of host plants of both Orobanche and Striga spp. In most cases, the compounds were shown to be isoprenoid and belong to one chemical class, collectively called the strigolactones, and suggested by many authors to be sesquiterpene lactones. However, this classification was never proven; hence, the biosynthetic pathways of the germination stimulants are unknown. We have used carotenoid mutants of maize (Zea mays) and inhibitors of isoprenoid pathways on maize, cowpea (Vigna unguiculata), and sorghum (Sorghum bicolor) and assessed the effects on the root exudate-induced germination of Striga hermonthica and Orobanche crenata. Here, we show that for these three host and two parasitic plant species, the strigolactone germination stimulants are derived from the carotenoid pathway. Furthermore, we hypothesize how the germination stimulants are formed. We also discuss this finding as an explanation for some phenomena that have been observed for the host-parasitic plant interaction, such as the effect of mycorrhiza on S. hermonthica infestation. PMID:16183851

Matusova, Radoslava; Rani, Kumkum; Verstappen, Francel W.A.; Franssen, Maurice C.R.; Beale, Michael H.; Bouwmeester, Harro J.

2005-01-01

185

Acetylesterase-Mediated Deacetylation of Pectin Impairs Cell Elongation, Pollen Germination, and Plant Reproduction[C][W  

PubMed Central

Pectin is a major component of the primary cell wall of higher plants. Some galacturonyl residues in the backbone of pectinaceous polysaccharides are often O-acetylated at the C-2 or C-3 position, and the resulting acetylesters change dynamically during the growth and development of plants. The processes involve both enzymatic acetylation and deacetylation. Through genomic sequence analysis, we identified a pectin acetylesterase (PAE1) from black cottonwood (Populus trichocarpa). Recombinant Pt PAE1 exhibited preferential activity in releasing the acetate moiety from sugar beet (Beta vulgaris) and potato (Solanum tuberosum) pectin in vitro. Overexpressing Pt PAE1 in tobacco (Nicotiana tabacum) decreased the level of acetyl esters of pectin but not of xylan. Deacetylation engendered differential changes in the composition and/or structure of cell wall polysaccharides that subsequently impaired the cellular elongation of floral styles and filaments, the germination of pollen grains, and the growth of pollen tubes. Consequently, plants overexpressing PAE1 exhibited severe male sterility. Furthermore, in contrast to the conventional view, PAE1-mediated deacetylation substantially lowered the digestibility of pectin. Our data suggest that pectin acetylesterase functions as an important structural regulator in planta by modulating the precise status of pectin acetylation to affect the remodeling and physiochemical properties of the cell wall's polysaccharides, thereby affecting cell extensibility. PMID:22247250

Gou, Jin-Ying; Miller, Lisa M.; Hou, Guichuan; Yu, Xiao-Hong; Chen, Xiao-Ya; Liu, Chang-Jun

2012-01-01

186

Epiphytic pink-pigmented methylotrophic bacteria enhance germination and seedling growth of wheat (Triticum aestivum) by producing phytohormone.  

PubMed

Methylotrophic bacteria were isolated from the phyllosphere of different crop plants such as sugarcane, pigeonpea, mustard, potato and radish. The methylotrophic isolates were differentiated based on growth characteristics and colony morphology on methanol supplemented ammonium mineral salts medium. Amplification of the mxaF gene helped in the identification of the methylotrophic isolates as belonging to the genus Methylobacterium. Cell-free culture filtrates of these strains enhanced seed germination of wheat (Triticum aestivum) with highest values of 98.3% observed using Methylobacterium sp. (NC4). Highest values of seedling length and vigour were recorded with Methylobacterium sp. (NC28). HPLC analysis of production by bacterial strains ranged from 1.09 to 9.89?gml(-1) of cytokinins in the culture filtrate. Such cytokinin producing beneficial methylotrophs can be useful in developing bio-inoculants through co-inoculation of pink-pigmented facultative methylotrophs with other compatible bacterial strains, for improving plant growth and productivity, in an environment-friendly manner. PMID:22200783

Meena, Kamlesh K; Kumar, Manish; Kalyuzhnaya, Marina G; Yandigeri, Mahesh S; Singh, Dhananjaya P; Saxena, Anil K; Arora, Dilip K

2012-05-01

187

Effects of live Saccharomyces cerevisiae cells on zoospore germination, growth, and cellulolytic activity of the rumen anaerobic fungus, Neocallimastix frontalis MCH3.  

PubMed

The effects of a live yeast strain of Saccharomyces cerevisiae have been investigated on zoospore germination, metabolism, and cellulolytic activity of the anaerobic rumen fungus Neocallimastix frontalis MCH3. The addition of yeast cells to a vitamin-deficient medium stimulated the germination of fungal zoospores, increased cellulose degradation and hydrogen, formate, lactate, and acetate production. Responses depended on the concentration of yeast cells added and on their viability. Yeast supplementation provided vitamins such as thiamine, which is essential for fungal growth and activity. These results demonstrate that yeasts could enhance plant cell wall colonization by N. frontalis. With certain diets, yeasts could therefore be a good tool to optimize the microbial degradation of lignocellulosic materials, but more research is needed to understand their mechanisms of action, so that they can be used with maximum efficiency as feed supplements. PMID:7549764

Chaucheyras, F; Fonty, G; Bertin, G; Gouet, P

1995-10-01

188

Gibberellic acid (GA3) enhance seed water uptake, germination and early seedling growth in sugar beet under salt stress.  

PubMed

The study was carried out to assess whether water uptake could be improved in sugar beet seeds and salt tolerance at the germination and early seedling stage by soaking the seeds for 10 h in distilled water (control), 100, 150 and 200 mg L(-1) GA3. Electrical Conductivity (EC) values of the NaCl solution were 0.0 (control), 4.7, 9.4 and 14.1 dS n(-1) NaCl. Priming increased the final germination percentage and the germination rate (1/t 50, where t 50 is the time to 50% of germination) under saline condition. Water uptake of primed seeds also increased significantly with increasing concentration of GA3 as compared to control. Priming also alleviated the adverse effect of salt stress on sugar beet in terms of roots and shoots lengths and fresh weights of plants, roots and shoots. PMID:19069553

Jamil, Muhammad; Rha, Eui Shik

2007-02-15

189

Common gas phase molecules from fungi affect seed germination and plant health in Arabidopsis thaliana.  

PubMed

Fungal volatile organic compounds (VOCs) play important ecophysiological roles in mediating inter-kingdom signaling with arthropods but less is known about their interactions with plants. In this study, Arabidopsis thaliana was used as a model in order to test the physiological effects of 23 common vapor-phase fungal VOCs that included alcohols, aldehydes, ketones, and other chemical classes. After exposure to a shared atmosphere with the 23 individual VOCs for 72hrs, seeds were assayed for rate of germination and seedling formation; vegetative plants were assayed for fresh weight and chlorophyll concentration. All but five of the VOCs tested (1-decene, 2-n-heptylfuran, nonanal, geosmin and -limonene) had a significant effect in inhibiting either germination, seedling formation or both. Seedling formation was entirely inhibited by exposure to 1-octen-3-one, 2-ethylhexanal, 3-methylbutanal, and butanal. As assayed by a combination of fresh weight and chlorophyll concentration, 2-ethylhexanal had a negative impact on two-week-old vegetative plants. Three other compounds (1-octen-3-ol, 2-ethylhexanal, and 2-heptylfuran) decreased fresh weight alone. Most of the VOCs tested did not change the fresh weight or chlorophyll concentration of vegetative plants. In summary, when tested as single compounds, fungal VOCs affected A. thaliana in positive, negative or neutral ways. PMID:25045602

Hung, Richard; Lee, Samantha; Rodriguez-Saona, Cesar; Bennett, Joan W

2014-01-01

190

Common gas phase molecules from fungi affect seed germination and plant health in Arabidopsis thaliana  

PubMed Central

Fungal volatile organic compounds (VOCs) play important ecophysiological roles in mediating inter-kingdom signaling with arthropods but less is known about their interactions with plants. In this study, Arabidopsis thaliana was used as a model in order to test the physiological effects of 23 common vapor-phase fungal VOCs that included alcohols, aldehydes, ketones, and other chemical classes. After exposure to a shared atmosphere with the 23 individual VOCs for 72hrs, seeds were assayed for rate of germination and seedling formation; vegetative plants were assayed for fresh weight and chlorophyll concentration. All but five of the VOCs tested (1-decene, 2-n-heptylfuran, nonanal, geosmin and -limonene) had a significant effect in inhibiting either germination, seedling formation or both. Seedling formation was entirely inhibited by exposure to 1-octen-3-one, 2-ethylhexanal, 3-methylbutanal, and butanal. As assayed by a combination of fresh weight and chlorophyll concentration, 2-ethylhexanal had a negative impact on two-week-old vegetative plants. Three other compounds (1-octen-3-ol, 2-ethylhexanal, and 2-heptylfuran) decreased fresh weight alone. Most of the VOCs tested did not change the fresh weight or chlorophyll concentration of vegetative plants. In summary, when tested as single compounds, fungal VOCs affected A. thaliana in positive, negative or neutral ways. PMID:25045602

2014-01-01

191

Spore germination  

Microsoft Academic Search

The germination of dormant spores of Bacillus species is the first crucial step in the return of spores to vegetative growth, and is induced by nutrients and a variety of non-nutrient agents. Nutrient germinants bind to receptors in the spores inner membrane and this interaction triggers the release of the spore cores huge depot of dipicolinic acid and cations, and

Peter Setlow

2003-01-01

192

Effects of Capsaicin on Plant Growth  

Microsoft Academic Search

Capsaicin, a possible allelochemical, caused growth inhibition of roots and shoots of alfalfa (Medicago sativa), cress (Lepidium sativum), lettuce (Lactuca sativa), crabgrass (Digitaria sanguinalis), timothy (Phleum pratense) and ryegrass (Lolium multiflorum), and suppressed their germination. Increasing the dose of capsaicin increased the inhibition. The concentrations for 50\\u000a % inhibition of the root growth were 2.7, 0.32, 2.1, 0.27, 0.29 and

H. Kato-Noguchi; Y. Tanaka

2003-01-01

193

Chemical investigation of Cyperus distans L. and inhibitory activity of scabequinone in seed germination and seedling growth bioassays.  

PubMed

Chemical investigation of the rhizomes of Cyperus distans (Cyperaceae) led to the identification of ?-ciperone, cyperotundone and scabequinone, besides other common constituents. Complete assignment of the (13)C NMR data of scabequinone is being published for the first time. The inhibitory effects of C. distans extracts and scabequinone on the seed germination and seedling growth of Mimosa pudica, Senna obtusifolia and Pueraria phaseoloides were evaluated. Seed germination inhibition bioassay revealed that S. obtusifolia (52-53%) was more sensitive to the hexane and the methanol extracts at 1% than M. pudica (0-10%). Scabequinone at 250mgL(-1) displayed seed germination inhibitions more than 50% and radicle growth reduction of more than 35% of the test species S. obtusifolia and P. phaseoloides, while the hypocotyl growth of M. pudica was significantly affected (>50%) by the quinone at the same concentration. These results demonstrate that scabequinone contributes to the overall inhibitory activities of C. distans. PMID:24941231

Vilhena, Karyme S S; Guilhon, Giselle Maria Skelding Pinheiro; Zoghbi, Maria das Graas B; Santos, Lourivaldo Silva; Souza Filho, Antonio Pedro Silva

2014-12-01

194

Does plant-derived smoke affect seed germination in dominant woody species of the Mediterranean matorral of central Chile?  

Microsoft Academic Search

Studies performed in the fire-prone Mediterranean-type climate shrublands of Australia, California, and South Africa have shown that plant-derived smoke enhances seed germination in many species. Unlike other areas with similar climate, central Chile stands out for the absence of natural fires, suggesting that smoke may not be expected to promote germination. However, anthropogenic fires have been frequent since several millennia,

S. Gmez-Gonzlez; A. Sierra-Almeida; L. A. Cavieres

2008-01-01

195

Eupatoriochromene and encecalin, plant growth regulators from yellow starthistle ( Centaurea solstitialis L. )  

Microsoft Academic Search

Two chromenes, eupatoriochromene (1) and encecalin (2), have been isolated from yellow starthistle (Centaurea solstitialis L.). Both chromenes retard seed germination and reduce radicle and hypocotyl growth of weed and crop plant seedlings. In addition,1 increases adventitious root formation of mung bean cuttings.

Glory B. Merrill

1989-01-01

196

Eupatoriochromene and encecalin, plant growth regulators from yellow starthistle (Centaurea solstitialis L.).  

PubMed

Two chromenes, eupatoriochromene (1) and encecalin (2), have been isolated from yellow starthistle (Centaurea solstitialis L.). Both chromenes retard seed germination and reduce radicle and hypocotyl growth of weed and crop plant seedlings. In addition,1 increases adventitious root formation of mung bean cuttings. PMID:24272297

Merrill, G B

1989-07-01

197

Increase of seed germination, growth and membrane integrity of wheat seedlings by exposure to static and a 10-KHz electromagnetic field.  

PubMed

There is a large body of experimental data demonstrating various effects of magnetic field (MF) on plants growth and development. Although the mechanism(s) of perception of MF by plants is not yet elucidated, there is a possibility that like other stimuli, MF exerts its effects on plants by changing membrane integrity and conductance of its water channels, thereby influencing growth characteristics. In this study, the seeds of wheat (Triticum aestivum L. cv. Kavir) were imbibed in water overnight and then treated with or without a 30-mT static magnetic field (SMF) and a 10-kHz electromagnetic field (EMF) for 4 days, each 5h. Water uptake of seeds reduced 5h of the treatment with EMF but did not show changes in SMF treatment. Exposure to both magnetic fields did not affect germination percent of the seeds but increased the speed of germination, compared to the control group. Treatment with EMF significantly reduced seedling length and subsequently vigor index I, while SMF had no effects on these parameters. Both treatments significantly increased vigor index II, compared to the control group. These treatments also remarkably increased catalase activity and proline contents of seedlings but reduced the activity of peroxidase, the rate of lipid peroxidation and electrolyte leakages of membranes. The results suggest promotional effects of EMFs on membrane integrity and growth characteristics of wheat seedlings. PMID:23343429

Payez, Atefeh; Ghanati, Faezeh; Behmanesh, Mehrdad; Abdolmaleki, Parviz; Hajnorouzi, Abazar; Rajabbeigi, Elham

2013-12-01

198

The Mars Plant Growth Experiment and Implications for Planetary Protection  

NASA Astrophysics Data System (ADS)

Plants are the ultimate and necessary solution for O2 production at a human base on Mars. Currently it is unknown if seeds can germinate on the Martian surface. The Mars Plant growth experiment (MPX) is a proposal for the first step in the development of a plant- based O2 production system by demonstrating plant germination and growth on the Martian surface. There is currently no planetary protection policy in place that covers plants on the Martian surface. We describe a planetary protection plan in compliance with NASA and COSPAR policy for a closed plant growth chamber on a Mars rover. We divide the plant growth chamber into two categories for planetary protection, the Outside: the outside of the chamber exposed to the Martian environment, and the Inside: the inside of the chamber which is sealed off from Mars atmosphere and contains the plant seeds and ancillary components for seed growth. We will treat outside surfaces of the chamber as other outside surfaces on the rover, wiped with a mixture of isopropyl alcohol and water as per Category IVb planetary protection requirements. All internal components of the MPX except the seeds and camera (including the water system, the plant growth stage and interior surface walls) will be sterilized by autoclave and subjected to sterilizing dry heat at a temperature of 125C at an absolute humidity corresponding to a relative humidity of less than 25 percent referenced to the standard conditions of 0C and 760 torr pressure. The seeds and internal compartments of the MPX in contact with the growth media will be assembled and tested to be free of viable microbes. MPX, once assembled, cannot survive Dry Heat Microbial Reduction. The camera with the radiation and CO2 sensors will be sealed in their own container and vented through HEPA filters. The seeds will be vernalized (microbe free) as per current Space Station methods described by Paul et al. 2001. Documentation of the lack of viable microbes on representative seeds from the same seed lot as used in the flight unit and lack of viable microbes in the interior of the MPX will be confirmed by the assay methods outlined in NASA HDBK 6022. In this method surfaces are swabbed and the cells collected on the swabs are extracted and then cultured following a standard protocol. All operations involving the manipulation of sterile items and sample processing shall be performed in laminar flow environments meeting Class 100 air cleanliness requirements of Federal Standard 209B. The entire MPX will be assembled in a sterile environment within a month of launch if possible, but could withstand an earlier assembly if required.

Smith, Heather

199

Density of intraspecific competitors determines the occurrence and benefits of accelerated germination.  

PubMed

Germination is a key process in plant recruitment and population dynamics, and seeds are expected to be under strong selection pressure to germinate under conditions that maximize subsequent plant survival. Increased rates of germination (i.e., accelerated germination) may occur in competitive environments. We examined the effects of conspecific density on the timing of germination of seeds of a bird-dispersed plant, Phytolacca americana (Phytolaccaceae, L.), in three different competitive environments. By comparing germination of seeds sown at the same time at different densities, we quantify the benefits of accelerated germination under conditions in which differences in performance among seedlings are attributable to germination timing only, and not to being sown at different times. We find that although the probability of germination is unchanged, the time to initiation of germination is significantly shorter when competition is greater. We also show that plants that germinate earlier are larger and have higher growth rates because they have more time to grow without competitors. Our work demonstrates that shifts in germination timing in response to competition can yield significant dividends for seeds that germinate earliest, but we caution that the magnitude and consequences of accelerated germination will likely depend on the competitive neighborhood. PMID:21622431

Orrock, John L; Christopher, Cory C

2010-04-01

200

Seed priming with chitosan improves maize germination and seedling growth in relation to physiological changes under low temperature stress.  

PubMed

Low temperature stress during germination and early seedling growth is an important constraint of global production of maize. The effects of seed priming with 0.25%, 0.50%, and 0.75% (w/v) chitosan solutions at 15 degrees C on the growth and physiological changes were investigated using two maize (Zea mays L.) inbred lines, HuangC (chilling-tolerant) and Mo17 (chilling-sensitive). While seed priming with chitosan had no significant effect on germination percentage under low temperature stress, it enhanced germination index, reduced the mean germination time (MGT), and increased shoot height, root length, and shoot and root dry weights in both maize lines. The decline of malondialdehyde (MDA) content and relative permeability of the plasma membrane and the increase of the concentrations of soluble sugars and proline, peroxidase (POD) activity, and catalase (CAT) activity were detected both in the chilling-sensitive and chilling-tolerant maize seedlings after priming with the three concentrations of chitosan. HuangC was less sensitive to responding to different concentrations of chitosan. Priming with 0.50% chitosan for about 60 approximately 64 h seemed to have the best effects. Thus, it suggests that seed priming with chitosan may improve the speed of germination of maize seed and benefit for seedling growth under low temperature stress. PMID:19489108

Guan, Ya-jing; Hu, Jin; Wang, Xian-ju; Shao, Chen-xia

2009-06-01

201

Germination traits explain soil seed persistence across species: the case of Mediterranean annual plants in cereal fields  

PubMed Central

Background and Aims Seed persistence in the soil under field conditions is an important issue for the maintenance of local plant populations and the restoration of plant communities, increasingly so in the light of rapidly changing land use and climate change. Whereas processes important for dispersal in space are well known, knowledge of processes governing dispersal in time is still limited. Data for morphological seed traits such as size have given contradictory results for prediction of soil seed persistence or cover only a few species. There have been few experimental studies on the role of germination traits in determining soil seed persistence, while none has studied their predictive value consistently across species. Delayed germination, as well as light requirements for germination, have been suggested to contribute to the formation of persistent seed banks. Moreover, diurnally fluctuating temperatures can influence the timing of germination and are therefore linked to seed bank persistence. Methods The role of germination speed measured by T50 (days to germination of 50 % of all germinated seeds), light requirement and reaction to diurnally fluctuating temperatures in determining seed persistence in the soil was evaluated using an experimental comparative data set of 25 annual cereal weed species. Key Results It is shown that light requirements and slow germination are important features to maintain seeds ungerminated just after entering the soil, and hence influence survival of seeds in the soil. However, the detection of low diurnally fluctuating temperatures enhances soil seed bank persistence by limiting germination. Our data further suggest that the effect of diurnally fluctuating temperatures, as measured on seeds after dispersal and dry storage, is increasingly important to prevent fatal germination after longer burial periods. Conclusions These results underline the functional role of delayed germination and light for survival of seeds in the soil and hence their importance for shaping the first part of the seed decay curve. Our analyses highlight the detection of diurnally fluctuating temperatures as a third mechanism to achieve higher soil seed persistence after burial which interacts strongly with season. We therefore advocate focusing future research on mechanisms that favour soil seed persistence after longer burial times and moving from studies of morphological features to exploration of germination traits such as reaction to diurnally fluctuating temperatures. PMID:21224268

Saatkamp, Arne; Affre, Laurence; Dutoit, Thierry; Poschlod, Peter

2011-01-01

202

IAA production during germination of Orobanche spp. seeds  

Microsoft Academic Search

Broomrapes (Orobanche spp.) are parasitic plants, whose growth and development fully depend on the nutritional connection established between the parasite and the roots of the respective host plant. Phytohormones are known to play a role in establishing the specific Orobanchehost plant interaction.The first step in the interaction is seed germination triggered by a germination stimulant secreted by the host-plant roots.

Slavtcho Slavov; Henry van Onckelen; Rossitza Batchvarova; Atanas Atanassov; Els Prinsen

2004-01-01

203

Plant-in-chip: Microfluidic system for studying root growth and pathogenic interactions in Arabidopsis  

NASA Astrophysics Data System (ADS)

We report a microfluidic platform for the hydroponic growth of Arabidopsis plants with high-resolution visualization of root development and root-pathogen interactions. The platform comprises a set of parallel microchannels with individual input/output ports where 1-day old germinated seedlings are initially placed. Under optimum conditions, a root system grows in each microchannel and its images are recorded over a 198-h period. Different concentrations of plant growth media show different root growth characteristics. Later, the developed roots are inoculated with two plant pathogens (nematodes and zoospores) and their physicochemical interactions with the live root systems are observed.

Parashar, Archana; Pandey, Santosh

2011-06-01

204

Allelopathic effects of juglone on germination and growth of several herbaceous and woody species.  

PubMed

Laboratory experiments were conducted to determine juglone sensitivity of 16 species (Trifolium incarnatum, Coronilla varia, Vicia villosa, Lespedeza stipulacea, L. cuneata, Acer ginnala, Caragana arbor-escens, Elaegnus angustifolia, E. umbellata, Lonicera maackii, Quercus alba, Fraxinus americana, Liriodendron tulipifera, Alnus glutinosa, Pinus strobus, andP. sylvestris) being considered for mixed plantings withJugions nigra (black walnut). All species were sensitive to juglone, but seed germination and radicle elongation were less affected than shoot elongation and dry weight accumulation. Seed germination and radicle elongation were affected by juglone in 6 and 11 species, respectively, mainly by the higher concentrations (10(-3) M and 10(-4) M). Shoot elongation and dry weight accumulation of all species were affected by juglone; many species were sensitive to concentrations as low as 10(-6) M. Seedlings of all species were severely wilted and eventually killed by 10(-3) M juglone, and most were chlorotic and severely retarded by 10(-4) M juglone. Seedlings inhibited by 10(-6) M and 10(-5) M juglone did not showany visible signs of injury. Based on the effects on seedling shoot elongation and dry weight accumulation, the five species found to be most sensitive to juglone were:Lonicera maackii, Lespedeza cuneata, Trifolium incarnatum, Alnus glutinosa, and Elaeagnus umbellata. PMID:24407348

Rietveld, W J

1983-02-01

205

Phenolics from Ageratina adenophora roots and their phytotoxic effects on Arabidopsis thaliana seed germination and seedling growth.  

PubMed

A bioassay-directed phytochemical study was conducted to investigate potential allelochemicals in the roots of the invasive plant Ageratina adenophora. Eleven phenolic compounds, including seven new ones, 7-hydroxy-8,9-dehydrothymol 9-O-trans-ferulate (1), 7-hydroxythymol 9-O-trans-ferulate (2), 7,8-dihydroxythymol 9-O-trans-ferulate (3), 7,8-dihydroxythymol 9-O-cis-ferulate (4), methyl (7R)-3-deoxy-4,5-epoxy-D-manno-2-octulosonate 8-O-trans-p-coumarate (5), methyl (7R)-3-deoxy-4,5-epoxy-D-manno-2-octulosonate 8-O-cis-p-coumarate (6), and 3-(2-hydroxyphenyl)propyl methyl malonate (7), were isolated from a bioactive subfraction of the ethanol extract of the roots of A. adenophora. The new structures were established on the basis of detailed spectroscopic analysis. The potential phytotoxic effects of these compounds on the germination of Arabidopsis thaliana seeds were tested by a filter paper assay. Compound 7 and known compounds 3-(2-hydroxyphenyl)-1-propanol (8) and o-coumaric acid (9) remarkably showed inhibition activity against Arabidopsis seed germination at a concentration of 1.0 mM. Compounds 1, 2, 5, 6, and 10 showed slight inhibitory activity at the test concentration after treatment for 3 days, while the other compounds showed no obvious inhibitory effects. Moreover, 7-9 were further found to show obvious inhibitory activity on retarding the seedling growth of Ar. thaliana cultured in soil medium. PMID:24180556

Zhou, Zhong-Yu; Liu, Wan-Xue; Pei, Gang; Ren, Hui; Wang, Jing; Xu, Qiao-Lin; Xie, Hai-Hui; Wan, Fang-Hao; Tan, Jian-Wen

2013-12-01

206

EFFECT OF GROWTH REGULATORS AND OSMOTICA IN ALLEVIATING SALINITY EFFECTS ON THE GERMINATION OF SALICORNIA UTAHENSIS  

Microsoft Academic Search

Salicornia utahensis Tiderstrom is a perennial halophyte from the family Chenopodiaceae and is widely distributed in brackish water playas of northern Utah. Salicornia utahensis produces seeds under high salinity and deposits its seed on saline soil. Seeds showed only 65% germination in distilled water. Seed germination decreased with the increase in salinity and less than 5% seeds germinated at 900

BILQUEES GUL; M. AJMAL KHAN

207

Plant responses to plant growth-promoting rhizobacteria  

Microsoft Academic Search

Non-pathogenic soilborne microorganisms can promote plant growth, as well as suppress diseases. Plant growth promotion is\\u000a taken to result from improved nutrient acquisition or hormonal stimulation. Disease suppression can occur through microbial\\u000a antagonism or induction of resistance in the plant. Several rhizobacterial strains have been shown to act as plant growth-promoting\\u000a bacteria through both stimulation of growth and induced systemic

L. C. van Loon

2007-01-01

208

Long-living lotus: germination and soil {gamma}-irradiation of centuries-old fruits, and cultivation, growth, and phenotypic abnormalities of offspring.  

PubMed

Sacred lotus (Nelumbo nucifera) has been cultivated as a crop in Asia for thousands of years. An ?1300-yr-old lotus fruit, recovered from an originally cultivated but now dry lakebed in northeastern China, is the oldest germinated and directly (14)C-dated fruit known. In 1996, we traveled to the dry lake at Xipaozi Village, China, the source of the old viable fruits. We identified all of the landmarks recorded by botanist Ichiro Ohga some 80 yr ago when he first studied the deposit, but found that the fruits are now rare. We (1) cataloged a total of 60 lotus fruits; (2) germinated four fruits having physical ages of 200-500 yr by (14)C dating; (3) measured the rapid germination of the old fruits and the initially fast growth and short dormancy of their seedlings; (4) recorded abnormal phenotypes in their leaves, stalks, roots, and rhizomes; (5) determined ?-radiation of ?2.0 mGy/yr in the lotus-bearing beds; and (6) measured stratigraphic sequences of the lakebed strata. The total ?-irradiation of the old fruits of 0.1-3 Gy (gray, the unit of absorbed dosage defined as 1 joule/kg; 1 Gy = 100 rad), evidently resulting in certain of the abnormal phenotypes noted in their seedlings, represents the longest natural radiobiology experiment yet recorded. Most of the lotus abnormalities resemble those of chronically irradiated plants exposed to much higher irradiances. Though the chronic exposure of the old fruits to low-dose ?-radiation may be responsible in part for the notably weak growth and mutant phenotypes of the seedlings, it has not affected seed viability. All seeds presumably repair cellular damage before germination. Understanding of repair mechanisms in the old lotus seeds may provide insight to the aging process applicable also to other organisms. PMID:21669732

Shen-Miller, J; Schopf, J William; Harbottle, Garman; Cao, Rui-Ji; Ouyang, Shu; Zhou, Kun-Shu; Southon, John R; Liu, Guo-Hai

2002-02-01

209

Effects of bilberry ( Vaccinium myrtillus L.) litter on seed germination and early seedling growth of four boreal tree species  

Microsoft Academic Search

Laboratory and greenhouse bioassays were used to test for inhibitory effects of senescent and decomposed leaves and aqueous extract from bilberry (Vaccinium myrtillus L.) against seed germination and seedling growth of aspen (Populus tremula L.), birch (Betula pendula Roth.), Scots pine (Pinus sylvestris L.), and Norway spruce [Picea abies (L.) Karst.]. Aqueous extracts from bilberry leaves were inhibitory to aspen

Anders Jderlund; Olle Zackrisson; Marie-Charlotte Nilsson

1996-01-01

210

Assessment of toxicity of heavy metal ion combinations on spore germination and protonemal growth of Polytrichum commune  

Microsoft Academic Search

Protonemal growth and percent of spore germination of Polytrichum commune were used to assess toxicities of the divalent ions of three heavy metals- Cu, Cd, and Zn- evaluated singly and in two- and three-way combinations of equal weight. In heavy metal rankings of toxicity and in sensitivity of response, both parameters yielded comparable results. Synergistic toxic responses were generated by

P. C. Francis; R. L. Petersen

2009-01-01

211

S1PR2 links germinal center confinement and growth regulation  

PubMed Central

Summary Germinal centers (GCs) are sites of rapid B-cell proliferation and somatic mutation. These ovoid structures develop within the center of follicles and grow to a stereotypic size. The cell migration and interaction dynamics underlying GC B-cell selection events are currently under intense scrutiny. In recent work, we identified a role for a migration inhibitory receptor, S1PR2, in promoting GC B-cell confinement to GCs. S1PR2 also dampens Akt activation and deficiency in S1PR2 or components of its signaling pathway result in a loss of growth control in chronically stimulated mucosal GCs. Here we detail present understanding of S1PR2 and S1P biology as it pertains to GC B cells and place this information in the context of a current model of GC function. PMID:22500830

Green, Jesse A.; Cyster, Jason G.

2012-01-01

212

An effective system to produce smoke solutions from dried plant tissue for seed germination studies1  

PubMed Central

Premise of the study: An efficient and inexpensive system was developed to produce smoke solutions from plant material to research the influence of water-soluble compounds from smoke on seed germination. Methods and Results: Smoke solutions (300 mL per batch) were produced by burning small quantities (100200 g) of dried plant material from a range of species in a bee smoker attached by a heater hose to a side-arm flask. The flask was attached to a vacuum water aspirator, to pull the smoke through the water. The entire apparatus was operated in a laboratory fume hood. Conclusions: Compared with other smoke solution preparation systems, the system described is easy to assemble and operate, inexpensive to build, and effective at producing smoke solutions from desired species in a small indoor space. Quantitative measurements can be made when using this system, allowing for replication of the process.

Coons, Janice; Coutant, Nancy; Lawrence, Barbara; Finn, Daniel; Finn, Stephanie

2014-01-01

213

Plant perceptions of plant growth-promoting Pseudomonas.  

PubMed Central

Plant-associated Pseudomonas live as saprophytes and parasites on plant surfaces and inside plant tissues. Many plant-associated Pseudomonas promote plant growth by suppressing pathogenic micro-organisms, synthesizing growth-stimulating plant hormones and promoting increased plant disease resistance. Others inhibit plant growth and cause disease symptoms ranging from rot and necrosis through to developmental dystrophies such as galls. It is not easy to draw a clear distinction between pathogenic and plant growth-promoting Pseudomonas. They colonize the same ecological niches and possess similar mechanisms for plant colonization. Pathogenic, saprophytic and plant growth-promoting strains are often found within the same species, and the incidence and severity of Pseudomonas diseases are affected by environmental factors and host-specific interactions. Plants are faced with the challenge of how to recognize and exclude pathogens that pose a genuine threat, while tolerating more benign organisms. This review examines Pseudomonas from a plant perspective, focusing in particular on the question of how plants perceive and are affected by saprophytic and plant growth-promoting Pseudomonas (PGPP), in contrast to their interactions with plant pathogenic Pseudomonas. A better understanding of the molecular basis of plant-PGPP interactions and of the key differences between pathogens and PGPP will enable researchers to make more informed decisions in designing integrated disease-control strategies and in selecting, modifying and using PGPP for plant growth promotion, bioremediation and biocontrol. PMID:15306406

Preston, Gail M

2004-01-01

214

Effects of Engineered Nanomaterials on Plants Growth: An Overview  

PubMed Central

Rapid development and wide applications of nanotechnology brought about a significant increment on the number of engineered nanomaterials (ENs) inevitably entering our living system. Plants comprise of a very important living component of the terrestrial ecosystem. Studies on the influence of engineered nanomaterials (carbon and metal/metal oxides based) on plant growth indicated that in the excess content, engineered nanomaterials influences seed germination. It assessed the shoot-to-root ratio and the growth of the seedlings. From the toxicological studies to date, certain types of engineered nanomaterials can be toxic once they are not bound to a substrate or if they are freely circulating in living systems. It is assumed that the different types of engineered nanomaterials affect the different routes, behavior, and the capability of the plants. Furthermore, different, or even opposing conclusions, have been drawn from most studies on the interactions between engineered nanomaterials with plants. Therefore, this paper comprehensively reviews the studies on the different types of engineered nanomaterials and their interactions with different plant species, including the phytotoxicity, uptakes, and translocation of engineered nanomaterials by the plant at the whole plant and cellular level.

Bagheri, Samira; Muhd Julkapli, Nurhidayatullaili; Juraimi, Abdul Shukor; Hashemi, Farahnaz Sadat Golestan

2014-01-01

215

Genetic variation in germination, growth, and survivorship of red maple in response to subambient  

E-print Network

, Durham, NC 27708, USA Abstract Genetic variation in plant response to atmospheric carbon dioxide (CO2) may have influenced paleo-vegetation dynamics and could determine how future elevated CO2 drives plant, population, and provenance ­ affect variation in the CO2 response of a species. This 2-year growth chamber

Mohan, Jacqueline E.

216

Novel light-activated protein kinases as key regulators of plant growth and development  

Microsoft Academic Search

Plants have evolved highly sensitive sensory photoreceptor systems to regulate various aspects of their growth and development.\\u000a Many responses such as seed germination, flowering and dormancy are controlled by red and far-red regions of the solar spectrum\\u000a through the phytochrome family of photoreceptors. However, several other responses such as stem growth inhibition, phototropism\\u000a and opening of stomata are controlled by

S. C. Maheshwari; J. P. Khurana; S. K. Sopory

1999-01-01

217

Germination, seedling growth and relative water content of shoot in different seed sizes of triticale under osmotic stress of water and NaCl  

Microsoft Academic Search

Effect of seed size (small, medium and large) on germination and seedling growth of triticale (xTriticosecale Witm. cv. Presto) at the different osmotic potential of NaCl and PEG solutions were determined in the present study. Germination tests were conducted under five osmotic potential levels (-0.45, -0.77, -1.03, -1.44 MPa, and Control) of PEG 6000 and NaCl. Germination percentage (%) at

Digdem Kaydan; Mehmet Yagmur

2008-01-01

218

Modeling the Effect of Density-Dependent Chemical Interference upon Seed Germination  

PubMed Central

A mathematical model is presented to estimate the effects of phytochemicals on seed germination. According to the model, phytochemicals tend to prevent germination at low seed densities. The model predicts that at high seed densities they may increase the probability of seed germination and the number of germinating seeds. Hence, the effects are reminiscent of the density-dependent effects of allelochemicals on plant growth, but the involved variables are germination probability and seedling number. The results imply that it should be possible to bypass inhibitory effects of allelopathy in certain agricultural practices and to increase the efficiency of nature conservation in several plant communities. PMID:18648596

Sinkkonen, Aki

2006-01-01

219

Modeling the Effect of Density-Dependent Chemical Interference Upon Seed Germination  

PubMed Central

A mathematical model is presented to estimate the effects of phytochemicals on seed germination. According to the model, phytochemicals tend to prevent germination at low seed densities. The model predicts that at high seed densities they may increase the probability of seed germination and the number of germinating seeds. Hence, the effects are reminiscent of the density-dependent effects of allelochemicals on plant growth, but the involved variables are germination probability and seedling number. The results imply that it should be possible to bypass inhibitory effects of allelopathy in certain agricultural practices and to increase the efficiency of nature conservation in several plant communities. PMID:19330163

Sinkkonen, Aki

2005-01-01

220

Effect of soil Cd addition on germination of native plant species  

Microsoft Academic Search

Soil Cd addition was found to adversely affect germination ofAndropogon scoparius, Monarda fistulosa, andRudbeckia hirta. Rudbeckia germination was found to be most sensitive to soil Cd addition andAndropogon germination most tolerant (b=?.0001). Soil cadmium concentrations sufficient to reduce germination by 25% were calculated to be 30 and 46 ?g Cd\\/g soil forRudbeckia andAndropogon respectively.

L. J. Miles; G. R. Parker

1980-01-01

221

The window of desiccation tolerance shown by early-stage germinating seedlings remains open in the resurrection plant, Xerophyta viscosa.  

PubMed

Resurrection plants are renowned for their vegetative desiccation tolerance (DT). While DT in vegetative tissues is rare in angiosperms, it is ubiquitous in mature orthodox seeds. During germination, seedlings gradually lose DT until they pass a point of no return, after which they can no longer survive dehydration. Here we investigate whether seedlings of the resurrection plant Xerophyta viscosa ever lose the capacity to establish DT. Seedlings from different stages of germination were dehydrated for 48 hours and assessed for their ability to recover upon rehydration. While a transient decline in the ability of X. viscosa seedlings to survive dehydration was observed, at no point during germination was the ability to re-establish DT completely lost in all seedlings. Pre-treatment of seedlings with PEG or sucrose reduced this transient decline, and improved the survival rate at all stages of germination. Additionally, we observed that the trait of poikilochlorophylly (or loss of chlorophyll) observed in adult X. viscosa leaves can be induced throughout seedling development. These results suggest that the window of DT seen in germinating orthodox seeds remains open in X. viscosa seedlings and that vegetative DT in Xerophyta species may have evolved from the ability to retain this program through to adulthood. PMID:24667896

Lyall, Rafe; Ingle, Robert A; Illing, Nicola

2014-01-01

222

The Window of Desiccation Tolerance Shown by Early-Stage Germinating Seedlings Remains Open in the Resurrection Plant, Xerophyta viscosa  

PubMed Central

Resurrection plants are renowned for their vegetative desiccation tolerance (DT). While DT in vegetative tissues is rare in angiosperms, it is ubiquitous in mature orthodox seeds. During germination, seedlings gradually lose DT until they pass a point of no return, after which they can no longer survive dehydration. Here we investigate whether seedlings of the resurrection plant Xerophyta viscosa ever lose the capacity to establish DT. Seedlings from different stages of germination were dehydrated for 48 hours and assessed for their ability to recover upon rehydration. While a transient decline in the ability of X. viscosa seedlings to survive dehydration was observed, at no point during germination was the ability to re-establish DT completely lost in all seedlings. Pre-treatment of seedlings with PEG or sucrose reduced this transient decline, and improved the survival rate at all stages of germination. Additionally, we observed that the trait of poikilochlorophylly (or loss of chlorophyll) observed in adult X. viscosa leaves can be induced throughout seedling development. These results suggest that the window of DT seen in germinating orthodox seeds remains open in X. viscosa seedlings and that vegetative DT in Xerophyta species may have evolved from the ability to retain this program through to adulthood. PMID:24667896

Lyall, Rafe; Ingle, Robert A.; Illing, Nicola

2014-01-01

223

Deficiency of maize starch-branching enzyme i results in altered starch fine structure, decreased digestibility and reduced coleoptile growth during germination  

PubMed Central

Background Two distinct starch branching enzyme (SBE) isoforms predate the divergence of monocots and dicots and have been conserved in plants since then. This strongly suggests that both SBEI and SBEII provide unique selective advantages to plants. However, no phenotype for the SBEI mutation, sbe1a, had been previously observed. To explore this incongruity the objective of the present work was to characterize functional and molecular phenotypes of both sbe1a and wild-type (Wt) in the W64A maize inbred line. Results Endosperm starch granules from the sbe1a mutant were more resistant to digestion by pancreatic ?-amylase, and the sbe1a mutant starch had an altered branching pattern for amylopectin and amylose. When kernels were germinated, the sbe1a mutant was associated with shorter coleoptile length and higher residual starch content, suggesting that less efficient starch utilization may have impaired growth during germination. Conclusions The present report documents for the first time a molecular phenotype due to the absence of SBEI, and suggests strongly that it is associated with altered physiological function of the starch in vivo. We believe that these results provide a plausible rationale for the conservation of SBEI in plants in both monocots and dicots, as greater seedling vigor would provide an important survival advantage when resources are limited. PMID:21599988

2011-01-01

224

Ecotoxicological effects of polycyclic musks and cadmium on seed germination and seedling growth of wheat (Triticum aestivum).  

PubMed

Single and joint toxic effects of polycyclic musks including 1,3,4,6,7,8-hexahydro-4,6,6,6,7,8,8-hexamethylcyclopenta[g]-2-benzopyran (HHCB) and 7-acetyl-1,1,3,4,4,6-hexamethyl-l,2,3,4-tetrahydronapthalene (AHTN) and cadmium (Cd) on seed germination and seedling growth of wheat (Triticum aestivum) were investigated. The results showed that the toxicity sequence of HHCB toxic to wheat seed germination and seedling growth was similar to that of AHTN, that is, germination rate > shoot elongation > root elongation, while the toxicity of Cd was in the sequence of root elongation > shoot elongation > germination rate, according to the LC50 and EC50 values. It is suggested that polycyclic musks and Cd had different toxicological mechanisms. Root and shoot elongation of wheat might be good bioindicators for the contamination of polycyclic musks and Cd in soil. The mixture of polycyclic musks and Cd had synergistic effects on T. aestivum according to the equi-toxic mixture approach when root elongation was selected as the toxicological endpoint. Thus, the joint toxicity of HHCB and Cd was significantly higher than the single toxicity of HHCB or Cd, which was also confirmed by the EC50 mix value of the mixture (EC50 mix = 0.530 TUmix). The EC(50mix) value of the mixture of AHTN and Cd was 0.614 TUmix, which indicated that the mixture toxicity was strengthened when AHTN coexisted with Cd. PMID:21462717

Chen, Cuihong; Zhou, Qixing; Bao, Yanyu; Li, Yaning; Wang, Ping

2010-01-01

225

Progesterone: Its occurrence in plants and involvement in plant growth  

Microsoft Academic Search

Progesterone is a mammalian gonadal hormone. In the current study, we identified and quantified progesterone in a range of higher plants by using GCMS and examined its effects on the vegetative growth of plants. The growth of Arabidopsis (Arabidopsis thaliana) seedlings was promoted by progesterone at low concentrations but suppressed at higher concentrations under both light and dark growth conditions.

Mayumi Iino; Takahito Nomura; Yuji Tamaki; Yumiko Yamada; Koichi Yoneyama; Yasutomo Takeuchi; Masaki Mori; Tadao Asami; Takeshi Nakano; Takao Yokota

2007-01-01

226

Efficiency of plant growth promoting rhizobacteria isolated from sand dunes of Chennai coastal area.  

PubMed

Plant Growth Promoting Rhizobacteria (PGPR) are beneficial bacteria that colonize the plant root and enhance the plant growth. The use of PGPR is steadily increasing in agriculture and offers an attractive way to replace chemical fertilizers, pesticides and supplements. In the present study, PGPR were isolated from 18 different rhizosphere soil samples of coastal sand dune plants, belonging to the genus Ipomoea sp. collected from the Chennai coastal area. For isolation of bacteria from soil samples, pour plate technique was followed. The rhizobacterial population was ranged from 4.4 x 10(6)-7.5 x 10(7) CFU g(-1). From that, 46 morphologically different bacterial strains were isolated. Among 46, 18 strains exhibited the production of Indole Acetic Acid. (IAA). When screened for phosphate solubilzing activity, six strains showed maximum activity. All these selected six strains were screened for seed germination among which these two strains (AMET1136 and AMET 1148) showed remarkable increase in the seed germination of black gram and green gram. For plant growth promotion, three types of treatments namely, seed bacterization, soil drenching and mixed (seed+soil) were carried out to check the potential of these two strains. Among that one strain which was identified as Pseudomonas sp. AMET1148 showed remarkable and significant increase in shoot length and root length of the tested plants. The study concluded that PGPR from coastal sand dund plants can be developed as plant growth promoters in agricultural crops. PMID:24175421

Muthezhilan, R; Sindhuja, B S; Hussain, A Jaffar; Jayaprakashvel, M

2012-08-15

227

Growth and yield of sweet corn ( Zea mays L.) cultivars in response to planting date and plastic mulch in a short-season environment  

Microsoft Academic Search

The optimum soil temperature required for sweet corn (Zea mays L.) germination is rarely achieved during spring planting in Newfoundland (NL), Canada. Plastic mulches have been used to improve establishment and hasten maturity during the short production season. The effects of cultivar, plastic mulch and planting date on plant growth, yield and quality traits of sweet corn were studied in

A. B. Kwabiah

2004-01-01

228

Germin-like proteins (GLPs) in cereal genomes: gene clustering and dynamic roles in plant defence.  

PubMed

The recent release of the genome sequences of a number of crop and model plant species has made it possible to define the genome organisation and functional characteristics of specific genes and gene families of agronomic importance. For instance, Sorghum bicolor, maize (Zea mays) and Brachypodium distachyon genome sequences along with the model grass species rice (Oryza sativa) enable the comparative analysis of genes involved in plant defence. Germin-like proteins (GLPs) are a small, functionally and taxonomically diverse class of cupin-domain containing proteins that have recently been shown to cluster in an area of rice chromosome 8. The genomic location of this gene cluster overlaps with a disease resistance QTL that provides defence against two rice fungal pathogens (Magnaporthe oryzae and Rhizoctonia solani). Studies showing the involvement of GLPs in basal host resistance against powdery mildew (Blumeria graminis ssp.) have also been reported in barley and wheat. In this mini-review, we compare the close proximity of GLPs in publicly available cereal crop genomes and discuss the contribution that these proteins, and their genome sequence organisation, play in plant defence. PMID:20683632

Breen, James; Bellgard, Matthew

2010-11-01

229

Factors influencing seed germination of medicinal plant Salvia aegyptiaca L. (Lamiaceae)  

PubMed Central

Salvia aegyptiaca is a xerophytic perennial herb belongs to the Lamiaceae family commonly used for medicinal purposes. Laboratory experiments were carried out to assess the effects of temperature and salinity on seed germination and recovery responses after transferring to distilled water. Temperatures between 10 and 40C seem to be favourable for the germination of this species. Germination was inhibited by either an increase or decrease in temperature from the optimum (30C). The highest germination percentages were obtained at 0mM NaCl; however, the increase of solution osmolalities progressively inhibited seed germination. The germination rate decreased with an increase in salinity for most of tested temperatures, but comparatively higher rates were obtained at 30C. Salt stress decreased both the percentage and the rate of germination. An interaction between salinity and temperature yielded no germination at 300mM NaCl. By experimental transfer to distilled water, S. aegyptiaca seeds that were exposed to moderately saline conditions recovered and keep their ability to germinate mostly at low temperatures. At 300mM NaCl, germination recovery decreased with increasing temperature and it was completely inhibited at 40C. PMID:23961132

Gorai, Mustapha; Gasmi, Hayet; Neffati, Mohamed

2011-01-01

230

Optimization of plant mineral nutrition under growth-limiting conditions in a lunar greenhouse  

NASA Astrophysics Data System (ADS)

It may be assumed that the first plants in a lunar base will play a main role in forming a protosoil of acceptable fertility needed for purposively growing second generation plants like wheat, rice, tulips, etc. The residues of the first-generation plants could be composted and transformed by microorganisms into a soil-like substrate within a loop of regenerative life support system. The lunar regolith may be used as a substrate for plant growth at the very beginning of a mission to reduce its cost. The use of microbial communities for priming plants will allow one to facilitate adaption to stressful conditions and to support the plant development under growth limiting conditions. Well-defined plant-associated bacteria were used for growing three cultivars to colonize French marigold (Tagetes patula L.) in anorthosite, a substrate of low bioavailability, analogous to a lunar rock. The consortium was composed of plant growth promoting rhizobacteria and the bacterium Paenibacillus sp. IMBG156 which stimulated seed germination, better plant development, and finally, the flowering of inoculated tagetes. In contrast, control plants grew poorly in the anorthosite and practically did not survive until flowering. Analysis of bacterial community composition showed that all species colonized plant roots, however, the rate of colonization depended on the allelopatic characteristics of marigold varieties. Bacteria of consortium were able to liberate some elements (Ca, Fe, Mn, Si, Ni, Cu, Zn) from substrate anorthosite. Plant colonization by mixed culture of bacterial strains resulted in the increase of accumulation of K, Mg, Mn by the plant and in the lowering of the level of toxic metal accumulation. It was assumed that a rationally assembled consortium of bacterial strains promoted germination of marygold seeds and supported the plant development under growth limiting conditions by means of bioleaching plant essential nutritional elements and by protecting the plant against hyperaccumulation of some toxic metals.

Zaets, I.; Voznyuk, T.; Kovalchuk, M.; Rogutskyy, I.; Lukashov, D.; Mytrokhyn, O.; Mashkovska, S.; Foing, B.; Kozyrovska, N.

231

Growth, Development and Flowering in Fast Plants  

NSDL National Science Digital Library

This document provides extensive background information about how Fast Plants grow and develop. The distinction between growth and development is explained. Also discussed is how genetics plus interactions with the environment produce variation during growth and development.

Program, The W.

232

Characterization of Peanut Germin-Like Proteins, AhGLPs in Plant Development and Defense  

PubMed Central

Background Germin-like superfamily members are ubiquitously expressed in various plant species and play important roles in plant development and defense. Although several GLPs have been identified in peanut (Arachis hypogaea L.), their roles in development and defense remain unknown. In this research, we study the spatiotemporal expression of AhGLPs in peanut and their functions in plant defense. Results We have identified three new AhGLP members (AhGLP3b, AhGLP5b and AhGLP7b) that have distinct but very closely related DNA sequences. The spatial and temporal expression profiles revealed that each peanut GLP gene has its distinct expression pattern in various tissues and developmental stages. This suggests that these genes all have their distinct roles in peanut development. Subcellular location analysis demonstrated that AhGLP2 and 5 undergo a protein transport process after synthesis. The expression of all AhGLPs increased in responding to Aspergillus flavus infection, suggesting AhGLPs' ubiquitous roles in defense to A. flavus. Each AhGLP gene had its unique response to various abiotic stresses (including salt, H2O2 stress and wound), biotic stresses (including leaf spot, mosaic and rust) and plant hormone stimulations (including SA and ABA treatments). These results indicate that AhGLPs have their distinct roles in plant defense. Moreover, in vivo study of AhGLP transgenic Arabidopsis showed that both AhGLP2 and 3 had salt tolerance, which made transgenic Arabidopsis grow well under 100 mM NaCl stress. Conclusions For the first time, our study analyzes the AhGLP gene expression profiles in peanut and reveals their roles under various stresses. These results provide an insight into the developmental and defensive roles of GLP gene family in peanut. PMID:23626720

Wang, Tong; Chen, Xiaoping; Zhu, Fanghe; Li, Haifen; Li, Ling; Yang, Qingli; Chi, Xiaoyuan; Yu, Shanlin; Liang, Xuanqiang

2013-01-01

233

Evaluation of Fungicides on Growth and Conidial Germination of Verticillium theobromae Isolated from Plantain  

NASA Astrophysics Data System (ADS)

An evaluation of three fungicides, namely, benomyl [methyl l-(butyl-carbamoyl)-2-benzimidazole carbamate], calixin (tridomorph) and dithane M-45 (mancozeb), was carried out for their inhibitory effects on Verticillium theobromae, the causal organism of cigar-end rot disease of plantain (Musa paradisiaca). The LD50 of calixin, benomyl and dithane M-45 in inhibiting mycelial growth, were 0.14, 0.98 and 535.17 g mL-1, respectively. Calixin was also the most effective in conidial germination inhibition with an LD50 of 21.78 g mL-1, as compared with dithane M-45 86.39 g mL-1 and benomyl 275.50 g mL-1. Germ tubes of the test organism were distorted by the fungicides at varying concentrations. Calixin had greater distortion effect at a lower concentration of 10 g mL-1, dithane M-45 (100 g mL-1) and benomyl (1000 g mL-1). The relevance of these results in relation to the control and management of cigar-end rot disease of plantain is discussed.

Igeleke, C. L.; Ayanru, D. K. G.

234

Investigation of pulsed electromagnetic field as a novel organic pre-sowing method on germination and initial growth stages of cotton.  

PubMed

Two different pre-sowing techniques have been investigated for their influence in an important industrial plant, namely cotton. Priming methods are very useful for agricultural practices because they improve crop seedling establishment, especially when environmental conditions are not optimum. Pulsed electromagnetic fields have been found to promote germination and improve early growth characteristics of cotton seedlings. Such priming techniques are especially valuable in organic cultivation, where chemical compounds are prohibited. PEG treatment showed an enhancement in some measurements, however in some cases the results were not statistically different compared to control plants. In addition, PEG treatment is a sophisticated method that is far from agricultural practices and farmers. In this research, two different ages of seeds were used (1- and 2-year-old) in order to investigate the promotory effects of priming techniques. Magnetic field treatment of 15min was found to stimulate germination percentage and to promote seeds, resulting in 85% higher values than control seeds under real field conditions. Furthermore, seeds that were treated with magnetic field performed better in terms of early-stage measurements and root characteristics. PMID:22268861

Bilalis, Dimitrios J; Katsenios, Nikolaos; Efthimiadou, Aspasia; Karkanis, Anestis; Efthimiadis, Panagiotis

2012-06-01

235

Oxygen requirement of germinating flax seeds  

NASA Astrophysics Data System (ADS)

Plant experiments in earth orbit are typically prepared on the ground and germinated in orbit to study gravity effects on the developing seedlings. Germination requires the breakdown of storage compounds, and this metabolism depends upon respiration, making oxygen one of the limiting factors in seed germination. In microgravity lack of run-off of excess water requires careful testing of water dispensation and oxygen availability. In preparation for a shuttle experiment (MICRO on STS-107) we studied germination and growth of flax ( Linum usitatissimum L.) seedlings in the developed hardware (Magnetic Field Chamber, MFC). We tested between four to 32 seeds per chamber (air volume = 14 mL) and after 36 h measured the root length. At 90 ?l O 2 per seed (32 seeds/chamber), the germination decreased from 94 to 69%, and the root length was reduced by 20%, compared to 8 seeds per chamber. Based on the percent germination and root length obtained in controlled gas mixtures between 3.6 and 21.6% O 2 we determined the lower limit of reliable germination to be 10 vol. % O 2 at atmospheric pressure. Although the oxygen available in the MFC's can support the intended number of seeds, the data show that seed storage and microgravity-related limitations may reduce germination.

Kuznetsov, Oleg A.; Hasenstein, K. H.

2003-05-01

236

Osmotic conditioning and shading on the germination and on the initial growth of Myracrodruon urundeuva Allemo seedlings.  

PubMed

The present work aimed to evaluate the osmotic conditioning and shading on the germination and on the initial growth of aroeira seedlings. The seeds were pre-imbibed in solutions with different concentrations of PEG (polyethylene glycol) and KNO3 and incubated at 10C and 20C temperatures, during 0 (control), 12 and 24 hours. After these periods, the seeds were dried until they reached the initial levels of humidity. After that, they were put for germinating in BOD (Biochemical Oxygen Demand) chambers, at alternated 20-30C. The control treatment and the pre-conditionings that presented the best results in BOD germination were selected, PEG (-1.0 MPa) + KNO3 (-1.0 MPa) and KNO3 (-1.0 MPa), with pre-imbibition for 12 h and incubated in BOD at 20C. The seeds were sowed on trays and then they were transplanted, keeping under a net covered with 50% and 70% of shading and at sunlight. The osmotic conditioning did not change the seeds germination in BOD, but the highest aerial part size was observed in PEG -1.0 MPa + KNO3-1.0 MPa treatment. The shading levels at 50% and 70% and the osmotic conditioning with PEG -1.0 MPa + KNO3-1.0 MPa offered a higher emergence in a greenhouse condition; however, at sunlight the seeds presented a better index of quality on the 145th day. PMID:23828353

Scalon, Silvana P Q; Mota, Leandro H S; Mussury, Rosilda M

2013-01-01

237

ABI5 acts downstream of ABI3 to execute an ABA-dependent growth arrest during germination  

Microsoft Academic Search

Summary The development of a germinating embryo into an autotrophic seedling is arrested under conditions of water deficit. This ABA-mediated developmental checkpoint requires the bZIP transcription factor ABI5. Here, we used abi3-1, which is also unable to execute this checkpoint, to investigate the relative role of ABI3 and ABI5 in this process. In wild-type Arabidopsis plants, ABI3 expression and activity

Luis Lopez-Molina; Sbastien Mongrand; Derek T. McLachlin; Brian T. Chait; Nam-Hai Chua

2002-01-01

238

The involvement of hydrogen peroxide in UV-B-inhibited pollen germination and tube growth of Paeonia suffruticosa and Paulownia tomentosa in vitro  

Microsoft Academic Search

Previous studies have shown that UV-B could affect pollen germination and tube growth. However, the mechanism of response of pollen to UV-B has not been clear. The purpose of this study was to investigate the role of hydrogen peroxide (H2O2) in the UV-B-induced reduction of in vitro pollen germination and tube growth of Paeonia suffruticosa Andr. and Paulownia tomentosa Steud.

Jun-Min He; Zhi-Hui Liu; Han Xu; Xiao-Ping She; Chen Huang

2006-01-01

239

A Putative Hydroxysteroid Dehydrogenase Involved in Regulating Plant Growth and Development1  

PubMed Central

We have functionally characterized an Arabidopsis (Arabidopsis thaliana) gene AtHSD1 (At5g50600) that encodes a protein with homology to animal 11-?-hydroxysteroid dehydrogenase (HSD). Transgenic Arabidopsis plants overexpressing AtHSD1 (designated AOHSD plants) under the control of the cauliflower mosaic virus 35S promoter showed increased growth and seed yield as well as increased tolerance of saline stress and reduced seed dormancy. In canola (Brassica napus), transgenic plants overexpressing AtHSD1 also outgrew wild-type plants. AOHSD phenotypes were similar to those of plants that overproduced brassinosteroids (BRs) or overexpressed the BR receptor gene BRI1. A loss-of-function hsd mutant produced by RNA interference displayed a semidwarfed phenotype with reduced sensitivity to BRs. In contrast, AOHSD plants were hypersensitive to BRs and exhibited increased catabolism of abscisic acid (ABA). Germination of AOHSD seeds was less sensitive to ABA, while hsd seed was more sensitive to ABA during germination. AtHSD transcription was rapidly induced by BR treatment in wild type and was expressed widely in aerial plant parts, especially vascular tissues. This study demonstrates that AtHSD1 is involved in regulating growth and development in plants and is likely to promote or mediate BR effects. The gene has significant potential for improving growth and yield of canola and other agricultural crops. PMID:17616511

Li, Fengling; Asami, Tadao; Wu, Xianzhong; Tsang, Edward W.T.; Cutler, Adrian J.

2007-01-01

240

Effect of plant growth promoting rhizobacteria on bacterial canker of tomato  

Microsoft Academic Search

Use of plant growth promoting rhizobacteria in managing bacterial canker disease of tomato was studied in the present work. Tomato seeds were treated with PGPR strains viz., Bacillus pumilus INR7, Bacillus pumilus SE34, Bacillus pumilus T4, Bacillus subtilis GBO3, Bacillus amyloliquefaciens IN937a and Brevibacillus brevis IPC11 were subjected for seed germination and seedling vigor. Among the PGPR strains tested, only

N Girish; S Umesha

2005-01-01

241

The restoration of sedge meadows: seed viability, seed germination requirements, and seedling growth of Carex species  

Microsoft Academic Search

To better understand how to establishCarex species from seed in created and restored wetlands, a series of experimental studies was conducted onCarex seed and seedlings. These studies included (1) the effect of seed age (1 to 18 months after collection) on viability and\\u000a germination, (2) storage conditions (+4,-4 or +4\\/-4C; wet or dry) on seed germination, (3) soil moisture on

Arnold G. van der Valk; Tony L. Bremholm; Elizabeth Gordon

1999-01-01

242

Germination in relation to salinity in some plants of salt marshes in Otago, New Zealand  

Microsoft Academic Search

Germination characteristics were examined for nine halophytes occurring on Otago salt marshes and were compared with two glycophytes. The seed of most halophytes remained dormant, but viable, in saline solution for at least several months. In comparison, of the two glycophyte species, one germinated in saline solution whereas the other suffered seed mortality. There was a correlation between the salt

T. R. Partridge; J. B. Wilson

1987-01-01

243

Comparative seed germination tests using ten plant species for toxicity assessment of a metal engraving effluent sample  

Microsoft Academic Search

An effluent sample was collected from the acid bath of a metal engraving plant where the sample had been pretreated with lime to pH 10.6. The sample was adjusted to pH 7.37 (and in a second test to 7.25) and diluted to a series of solutions using hard, standard water. The seed germination thod was employed to test the phytotoxicity

Wuncheng Wang; Paul H. Keturi

1990-01-01

244

Microgravity Effects on Plant Growth and Lignification  

Microsoft Academic Search

Lignin is a major cellular component of higher plants. One function of lignin is to support vertical plant growth in a gravity environment. Various investigators working in the 1 g environment have concluded that lignification is influenced by gravity. An experiment was designed for flight on Spacelab II to determine the effect of microgravity on lignification in young plant seedlings.

Joe R. Cowles; Richard Lemay; Gary Jahns

1988-01-01

245

Diterpenoid Alkaloids as Plant Growth Inhibitors  

Microsoft Academic Search

WE report here preliminary studies on the plant growth inhibitory activity of two diterpenoid alkaloids isolated from the common larkspur, Delphinium ajacis. Little is known about the possible metabolic or physiological action on plants of either terpenoids or alkaloids. The diterpenoid alkaloids are an unusual group of ``secondary metabolites'' produced by plants; they can be derived biogenetically from an isoprenoid

George R. Waller

1969-01-01

246

Plant growth promotion and Penicillium citrinum  

Microsoft Academic Search

BACKGROUND: Endophytic fungi are known plant symbionts. They produce a variety of beneficial metabolites for plant growth and survival, as well as defend their hosts from attack of certain pathogens. Coastal dunes are nutrient deficient and offer harsh, saline environment for the existing flora and fauna. Endophytic fungi may play an important role in plant survival by enhancing nutrient uptake

Sumera Afzal Khan; Muhammad Hamayun; Hyeokjun Yoon; Ho-Youn Kim; Seok-Jong Suh; Seon-Kap Hwang; Jong-Myeong Kim; In-Jung Lee; Yeon-Sik Choo; Ung-Han Yoon; Won-Sik Kong; Byung-Moo Lee; Jong-Guk Kim

2008-01-01

247

Plant hormones are versatile chemical regulators of plant growth  

Microsoft Academic Search

The plant hormones are a structurally unrelated collection of small molecules derived from various essential metabolic pathways. These compounds are important regulators of plant growth and mediate responses to both biotic and abiotic stresses. During the last ten years there have been many exciting advances in our understanding of plant hormone biology, including new discoveries in the areas of hormone

Aaron Santner; Luz Irina A Calderon-Villalobos; Mark Estelle

2009-01-01

248

Fabacyl acetate, a germination stimulant for root parasitic plants from Pisum sativum.  

PubMed

A germination stimulant, fabacyl acetate, was purified from root exudates of pea (Pisum sativum L.) and its structure was determined as ent-2'-epi-4a,8a-epoxyorobanchyl acetate [(3aR,4R,4aR,8bS,E)-4a,8a-epoxy-8,8-dimethyl-3-(((R)-4-methyl-5-oxo-2,5-dihydrofuran-2-yloxy)methylene)-2-oxo-3,3a,4,5,6,7,8,8b-decahydro-2H-indeno[1,2-b]furan-4-yl acetate], by 1D and 2D NMR spectroscopic, ESI- and EI-MS spectrometric, X-ray crystallographic analyses, and by comparing the (1)H NMR spectroscopic data and relative retention times (RR(t)) in LC-MS and GC-MS with those of synthetic standards prepared from (+)-orobanchol and (+)-2'-epiorobanchol. The (1)H NMR spectroscopic data and RR(t) of fabacyl acetate were identical with those of an isomer prepared from (+)-2'-epiorobanchol except for the opposite sign in CD spectra. This is the first natural ent-strigolactone containing an epoxide group. Fabacyl acetate was previously detected in root exudates of other Fabaceae plants including faba bean (Vicia faba L.) and alfalfa (Medicago sativa L.). PMID:19155028

Xie, Xiaonan; Yoneyama, Kaori; Harada, Yuta; Fusegi, Norio; Yamada, Yoichi; Ito, Satoshi; Yokota, Takao; Takeuchi, Yasutomo; Yoneyama, Koichi

2009-01-01

249

Spaceflight hardware for conducting plant growth experiments in space: the early years 1960-2000.  

PubMed

The best strategy for supporting long-duration space missions is believed to be bioregenerative life support systems (BLSS). An integral part of a BLSS is a chamber supporting the growth of higher plants that would provide food, water, and atmosphere regeneration for the human crew. Such a chamber will have to be a complete plant growth system, capable of providing lighting, water, and nutrients to plants in microgravity. Other capabilities include temperature, humidity, and atmospheric gas composition controls. Many spaceflight experiments to date have utilized incomplete growth systems (typically having a hydration system but lacking lighting) to study tropic and metabolic changes in germinating seedlings and young plants. American, European, and Russian scientists have also developed a number of small complete plant growth systems for use in spaceflight research. Currently we are entering a new era of experimentation and hardware development as a result of long-term spaceflight opportunities available on the International Space Station. This is already impacting development of plant growth hardware. To take full advantage of these new opportunities and construct innovative systems, we must understand the results of past spaceflight experiments and the basic capabilities of the diverse plant growth systems that were used to conduct these experiments. The objective of this paper is to describe the most influential pieces of plant growth hardware that have been used for the purpose of conducting scientific experiments during the first 40 years of research. PMID:12578007

Porterfield, D M; Neichitailo, G S; Mashinski, A L; Musgrave, M E

2003-01-01

250

Spaceflight hardware for conducting plant growth experiments in space: the early years 1960-2000  

NASA Technical Reports Server (NTRS)

The best strategy for supporting long-duration space missions is believed to be bioregenerative life support systems (BLSS). An integral part of a BLSS is a chamber supporting the growth of higher plants that would provide food, water, and atmosphere regeneration for the human crew. Such a chamber will have to be a complete plant growth system, capable of providing lighting, water, and nutrients to plants in microgravity. Other capabilities include temperature, humidity, and atmospheric gas composition controls. Many spaceflight experiments to date have utilized incomplete growth systems (typically having a hydration system but lacking lighting) to study tropic and metabolic changes in germinating seedlings and young plants. American, European, and Russian scientists have also developed a number of small complete plant growth systems for use in spaceflight research. Currently we are entering a new era of experimentation and hardware development as a result of long-term spaceflight opportunities available on the International Space Station. This is already impacting development of plant growth hardware. To take full advantage of these new opportunities and construct innovative systems, we must understand the results of past spaceflight experiments and the basic capabilities of the diverse plant growth systems that were used to conduct these experiments. The objective of this paper is to describe the most influential pieces of plant growth hardware that have been used for the purpose of conducting scientific experiments during the first 40 years of research. c2002 COSPAR. Published by Elsevier Science Ltd. All rights reserved.

Porterfield, D. M.; Neichitailo, G. S.; Mashinski, A. L.; Musgrave, M. E.

2003-01-01

251

The Putative E3 Ubiquitin Ligase ECERIFERUM9 Regulates Abscisic Acid Biosynthesis and Response during Seed Germination and Postgermination Growth in Arabidopsis1[W][OPEN  

PubMed Central

The ECERIFERUM9 (CER9) gene encodes a putative E3 ubiquitin ligase that functions in cuticle biosynthesis and the maintenance of plant water status. Here, we found that CER9 is also involved in abscisic acid (ABA) signaling in seeds and young seedlings of Arabidopsis (Arabidopsis thaliana). The germinated embryos of the mutants exhibited enhanced sensitivity to ABA during the transition from reversible dormancy to determinate seedling growth. Expression of the CER9 gene is closely related to ABA levels and displays a similar pattern to that of ABSCISIC ACID-INSENSITIVE5 (ABI5), which encodes a positive regulator of ABA responses in seeds. cer9 mutant seeds exhibited delayed germination that is independent of seed coat permeability. Quantitative proteomic analyses showed that cer9 seeds had a protein profile similar to that of the wild type treated with ABA. Transcriptomics analyses revealed that genes involved in ABA biosynthesis or signaling pathways were differentially regulated in cer9 seeds. Consistent with this, high levels of ABA were detected in dry seeds of cer9. Blocking ABA biosynthesis by fluridone treatment or by combining an ABA-deficient mutation with cer9 attenuated the phenotypes of cer9. Whereas introduction of the abi1-1, abi3-1, or abi4-103 mutation could completely eliminate the ABA hypersensitivity of cer9, introduction of abi5 resulted only in partial suppression. These results indicate that CER9 is a novel negative regulator of ABA biosynthesis and the ABA signaling pathway during seed germination. PMID:24812105

Zhao, Huayan; Zhang, Huoming; Cui, Peng; Ding, Feng; Wang, Guangchao; Li, Rongjun; Jenks, Matthew A.; Lu, Shiyou; Xiong, Liming

2014-01-01

252

Plant growth promoting potential of bacteria isolated on N free media from rhizosphere of Cassia occidentalis.  

PubMed

Plant growth promoting rhizobacteria (PGPR) are an attractive eco-friendly alternative to chemicals in agriculture. While the rhizospheres of crop plants have been well studied with the objective of screening PGPR, weeds, which play an important role in maintaining ecological balance, have largely been ignored. The rhizosphere of a luxuriantly growing, medicinal weed, Cassia occidentalis was analysed by enumerating PGPR on N free media from the most diverse stage of plant (determined by profiles obtained on denaturing gradient gel electrophoresis). Each isolate was tested for other plant growth promotion assays including production of cellulase, indole acetic acid (IAA), ammonia, HCN, siderophore and chitinase to select for ones possessing multi-trait plant growth promoting (PGP) properties. Selected isolates were used for bacterization of Vigna radiata and Vigna mungo to evaluate their efficacy in promoting plant's growth in seedling germination and axenic pot conditions. Thirty five isolates were analysed further for the array of PGP properties they exhibit. A total of 6 isolates were shortlisted on the basis of maximum traits positive, amount of phosphate solubilized and IAA produced. V. radiata responded well to seed bacterization during seedling germination. A maximum increase of approximately 36 and 60 % was observed for shoot and root length, respectively in V. radiata in axenic pot culture over control plants. Extensive branching of roots was also observed with isolate NL, which produced the maximum amount of IAA. Present study investigated the plant growth promoting isolates obtained on N free media in the rhizosphere of C. occidentalis, which have the potential to be used as inoculants for other crops. This provides a new dimension to the significance of weeds in agricultural ecosystems. The study opens up possibilities for utilization of this property of weeds in plant growth promotion, and subsequent enhancement of yield for agricultural crops. PMID:22806725

Arun, B; Gopinath, B; Sharma, Shilpi

2012-09-01

253

Smoke as a germination cue: a review  

Microsoft Academic Search

Slow combustion or burning of dry or green plant material from many sources produces volatile compounds that are water soluble and that stimulate the germination of many seeds with different dormancy strategies. The active principals are apparently produced around 160ndash;200 deg;C and are volatilized at higher temperatures. Once dissolved in water the active compounds also stimulate rooting, seedling growth and

N. A. C. Brown; J. van Staden

1997-01-01

254

Detection of parasitic plant suicide germination compounds using a high-throughput Arabidopsis HTL/KAI2 strigolactone perception system.  

PubMed

Strigolactones are terpenoid-based plant hormones that act as communication signals within a plant, between plants and fungi, and between parasitic plants and their hosts. Here we show that an active enantiomer form of the strigolactone GR24, the germination stimulant karrikin, and a number of structurally related small molecules called cotylimides all bind the HTL/KAI2 ?/? hydrolase in Arabidopsis. Strigolactones and cotylimides also promoted an interaction between HTL/KAI2 and the F-box protein MAX2 in yeast. Identification of this chemically dependent protein-protein interaction prompted the development of a yeast-based, high-throughput chemical screen for potential strigolactone mimics. Of the 40 lead compounds identified, three were found to have in planta strigolactone activity using Arabidopsis-based assays. More importantly, these three compounds were all found to stimulate suicide germination of the obligate parasitic plant Striga hermonthica. These results suggest that screening strategies involving yeast/Arabidopsis models may be useful in combating parasitic plant infestations. PMID:25126711

Toh, Shigeo; Holbrook-Smith, Duncan; Stokes, Michael E; Tsuchiya, Yuichiro; McCourt, Peter

2014-08-14

255

Allelopathic effects of weeds extracts against seed germination of some plants.  

PubMed

This study investigated the allelopathic effects of various weeds extracts on seed germination of 11 crop species. Most of the weed extracts tested had inhibitory effects on seed germination of common bean, tomato, pepper, squash, onion, barley, wheat, and corn at different application rates as compared with the 10% acetone control. Chickpea seed germination was inhibited by extracts of Solanum nigrum L., Chenopodium album L., and Matricaria chamomilla L. (10%, 20% and 22.5%, respectively) at the end of 21 day incubation period. However, Glycyrrhiza glabra L., Sorghum halepense (L.) Pers., and Reseda lutea L. extracts stimulated chickpea seed germination at the rates of 95%, 94%, and 93%, respectively, compared to control. It was concluded that some of the weed extracts tested in this study could be used as inhibitor while others could be used as stimulator for the crops. PMID:16161968

Kadioglu, Izzet; Yanar, Yusuf; Asav, Unal

2005-04-01

256

Effect of essential oils on Aspergillus spore germination, growth and mycotoxin production: a potential source of botanical food preservative  

PubMed Central

Objective To investigate effect of essential oils on Aspergillus spore germination, growth and mycotoxin production. Method In vitro antifungal and antiaflatoxigenic activity of essential oils was carried out using poisoned food techniques, spore germination assay, agar dilution assay, and aflatoxin arresting assay on toxigenic strains of Aspergillus species. Results Cymbopogon martinii, Foeniculum vulgare and Trachyspermum ammi (T. ammi) essential oils were tested against toxicogenic isolates of Aspergillus species. T. ammi oil showed highest antifungal activity. Absolute mycelial inhibition was recorded at 1 l/mL by essential oils of T. ammi. The oil also showed, complete inhibition of spore germination at a concentration of 2 l/mL. In addition, T. ammi oil showed significant antiaflatoxigenic potency by totally inhibiting aflatoxin production from Aspergillus niger and Aspergillus flavus at 0.5 and 0.75 l/mL, respectively. Cymbopogon martinii, Foeniculum vulgare and T. ammi oils as antifungal were found superior over synthetic preservative. Moreover, a concentration of 5?336.297 l/kg body weight was recorded for LC50 on mice indicating the low mammalian toxicity and strengthening its traditional reputations. Conclusions In conclusion, the essential oils from T. ammi can be a potential source of safe natural food preservative for food commodities contamination by storage fungi. PMID:25183114

Gemeda, Negero; Woldeamanuel, Yimtubezinash; Asrat, Daniel; Debella, Asfaw

2014-01-01

257

Plant photomorphogenesis and canopy growth  

NASA Technical Reports Server (NTRS)

An important motivation for studying photomorphogenesis is to understand the relationships among plant photophysiology in canopies, canopy productivity, and agronomic yield. This understanding is essential to optimize lighting systems used for plant farming in controlled environments (CE) and for the design of genetically engineered crop strains with altered photoresponses. This article provides an overview of some basic principles of plant photomorphogenesis in canopies and discusses their implications for (1) scaling up information on plant photophysiology from individual plants in CE to whole canopies in the field, and (2) designing lighting conditions to increase plant productivity in CE used for agronomic purposes (e.g. space farming in CE Life Support Systems). We concentrate on the visible (lambda between 400 and 700 nm) and far-infrared (FR; lambda greater than 700 nm) spectral regions, since the ultraviolet (UV; 280 to 400 nm) is covered by other authors in this volume.

Ballare, Carlos L.; Scopel, Ana L.

1994-01-01

258

Plant Growth Modelling and Applications: The Increasing Importance of Plant Architecture in Growth Models  

Microsoft Academic Search

Background Modelling plant growth allows us to test hypotheses and carry out virtual experiments concerning plant growth processes that could otherwise take years in field conditions. The visualization of growth simulations allows us to see directly and vividly the outcome of a given model and provides us with an instructive tool useful for agronomists and foresters, as well as for

THIERRY FOURCAUD; X IAOPENG Z HANG; A LEXIA S TOKES; H ANS L AMBERS; CHRISTIAN KORNER

2008-01-01

259

Effect of Environment on Plant Growth  

NSDL National Science Digital Library

The purpose of this plant biotechnology activity is to demonstrate the effect of changes in the environment on the growth and fertility of landscape grasses and crop grasses such as wheat and rice. Plants are placed in environments such as high salinity, cold, heat, or drought and learners observe the different reactions of the plants to these conditions. Learners compare the growth of treated plants to that of the control plants, which are grown under optimal conditions. Learners then discuss the desirability of breeding new types of plants that are better able to withstand these changes if they occur in the general environment. In the original description of the activity, the planting is prepared by the instructor as a demonstration, but learners could be involved in this process. This resource contains background information and questions for learners.

Stephens, Janice; Leach, Jan

2011-01-01

260

FgKin1 kinase localizes to the septal pore and plays a role in hyphal growth, ascospore germination, pathogenesis, and localization of Tub1 beta-tubulins in Fusarium graminearum.  

PubMed

The Kin1/Par-1/MARK kinases regulate various cellular processes in eukaryotic organisms. Kin1 orthologs are well conserved in fungal pathogens but none of them have been functionally characterized. Here, we show that KIN1 is important for pathogenesis and growth in two phytopathogenic fungi and that FgKin1 regulates ascospore germination and the localization of Tub1 ?-tubulins in Fusarium graminearum. The Fgkin1 mutant and putative FgKIN1(S172A) kinase dead (nonactivatable) transformants were characterized for defects in plant infection, sexual and asexual reproduction, and stress responses. The localization of FgKin1 and two ?-tubulins were examined in the wild-type and mutant backgrounds. Deletion of FgKIN1 resulted in reduced virulence and defects in ascospore germination and release. FgKin1 localized to the center of septal pores. FgKIN1 deletion had no effect on Tub2 microtubules but disrupted Tub1 localization. In the mutant, Tub1 appeared to be enriched in the nucleolus. In Magnaporthe oryzae, MoKin1 has similar functions in growth and infection and it also localizes to septal pores. The S172A mutation had no effect on the localization and function of FgKIN1 during sexual reproduction. These results indicate that FgKIN1 has kinase-dependent and independent functions and it specifically regulates Tub1 ?-tubulins. FgKin1 plays a critical role in ascospore discharge, germination, and plant infection. PMID:25078365

Luo, Yongping; Zhang, Hongchang; Qi, Linlu; Zhang, Shijie; Zhou, Xiaoying; Zhang, Yimei; Xu, Jin-Rong

2014-12-01

261

Gene expression profiles in promoted-growth rice seedlings that germinated from the seeds implanted by low-energy N+ beam  

PubMed Central

The stimulation effect that some beneficial agronomic qualities have exhibited in present-generation plants have also been observed due to ion implantation on plants. However, there is relatively little knowledge regarding the molecular mechanism of the stimulation effects of ion-beam implantation. In order to extend our current knowledge about the functional genes related to this stimulation effect, we have reported a comprehensive microarray analysis of the transcriptome features of the promoted-growth rice seedlings germinating from seeds implanted by a low-energy N+ beam. The results showed that 351 up-regulated transcripts and 470 down-regulated transcripts, including signaling proteins, kinases, plant hormones, transposable elements, transcription factors, non-coding protein RNA (including miRNA), secondary metabolites, resistance proteins, peroxidase and chromatin modification, are all involved in the stimulating effects of ion-beam implantation. The divergences of the functional catalog between the vacuum and ion implantation suggest that ion implantation is the principle cause of the ion-beam implantation biological effects, and revealed the complex molecular networks required to adapt to ion-beam implantation stress in plants, including enhanced transposition of transposable elements, promoted ABA biosynthesis and changes in chromatin modification. Our data will extend the current understanding of the molecular mechanisms and gene regulation of stimulation effects. Further research on the candidates reported in this study should provide new insights into the molecular mechanisms of biological effects induced by ion-beam implantation. PMID:22843621

Ya, Huiyuan; Chen, Qiufang; Wang, Weidong; Chen, Wanguang; Qin, Guangyong; Jiao, Zhen

2012-01-01

262

Enterobacter : Role in Plant Growth Promotion  

Microsoft Academic Search

\\u000a It is believed that inoculation with rhizobacteria containing plant growth promoting (PGP) characteristics consequently promote\\u000a root and shoot growth. Further evaluation of these bacteria exhibiting multiple PGP traits on soilplant system is needed\\u000a to uncover their efficacy as effective PGP rhizobacteria (PGPR) or PGP bacteria (PGPB) depending upon their nature. The genera\\u000a within the family Enterobacteriaceae that feature members described

Chaitanya Kumar Jha; Abhinav Aeron; Baldev V. Patel; Dinesh K. Maheshwari; Meenu Saraf

263

Plant hormones are versatile chemical regulators of plant growth.  

PubMed

The plant hormones are a structurally unrelated collection of small molecules derived from various essential metabolic pathways. These compounds are important regulators of plant growth and mediate responses to both biotic and abiotic stresses. During the last ten years there have been many exciting advances in our understanding of plant hormone biology, including new discoveries in the areas of hormone biosynthesis, transport, perception and response. Receptors for many of the major hormones have now been identified, providing new opportunities to study the chemical specificity of hormone signaling. These studies also reveal a surprisingly important role for the ubiquitin-proteasome pathway in hormone signaling. In addition, recent work confirms that hormone signaling interacts at multiple levels during plant growth and development. In the future, a major challenge will be to understand how the information conveyed by these simple compounds is integrated during plant growth. PMID:19377456

Santner, Aaron; Calderon-Villalobos, Luz Irina A; Estelle, Mark

2009-05-01

264

The effects of maternal salinity and seed environment on germination and growth in Iris hexagona  

Microsoft Academic Search

Seed germination and seedling establishment are determined by local environmental conditions as well as by the environment of the parental generation, resulting in a type of trans- generational phenotypic plasticity known as an inherited environmental effect. Parental effects should be adaptive in habitats where the selective environment is spatially and temporally predictable, and where parental effects confer a fitness advantage.

Peter A. Van Zandt; Susan Mopper

2004-01-01

265

Influence of Plasma Treatment on Wheat and Oat Germination and Early Growth  

Microsoft Academic Search

The aim of this paper is to show and discuss the influence of cold plasma treatment on a germination enhancement of wheat and oat caryopses in wider context. Wheat and oat corns have been stimulated by cold plasma discharge under power of 500 W, air gas flow of 200 ml\\/min for different time durations (from 0 to 2400 s). Wheat

Boena er; Petr patenka; Michal er; Nad?da Vrchotov; Iveta Hrukov

2010-01-01

266

Enhanced germination and gravitropism of soybean in a hypogeomagnetic field  

NASA Astrophysics Data System (ADS)

For the future manned space exploration, the duration of the missions would significantly in-crease. Investigating plant growth and development under the space environmental conditions is of essential importance for the food supply projects for the astronauts. Hypogeomagnetic field (HGMF), namely, extremely low magnetic field, is one of the main characters of the space environment. Germination is the first vital step of plant growth and development, which determines the final yield of plants. The effect of HGMF on plant growth, especially early ger-mination, still remains open. In this study, we established a hypogeomagnetic field (HGMF) incubation system, the remnant magnetic field inside no more than 250 nT. Soybean seeds were incubated at 25 in HGMF, and the very beginning of soybean germination, from water ab-sorbance of cotyledon to radicle emergence, was examined within 24 h. Our results showed that the germination ratio and weight ratio of emerged soybean radicles were markedly increased during germination in HGMF. Furthermore, the tropism angle of emerged radicle with gravity in HGMF was statistically smaller than that in GMF when the radicle direction was placed opposite to gravity before germination. These results indicate that the germination and gravit-ropism of soybean is enhanced in a hypogeomagnetic environment, This is a new finding about the early seed germination in such a low environmental magnetic field which is comparable to the magnetic field of Lunar Swirls on the Moon (a few hundred nT), and it might provide new perspectives on the space science researches concerning plant growth and food supply.

Mo, Weichuan

267

Consequences of clonal growth for plant mating  

Microsoft Academic Search

By affecting the number and the spatial distribution of flowering units (i.e., ramets), clonal growth can influence pollen transfer between plants and thus affect mating opportunities. In this paper I review some recent work that attests the importance of clonal growth for pollination patterns. A major aspect concerns the increase in floral display through the multiplication of flowering ramets. Although

Anne Charpentier

2001-01-01

268

Plant Growth Under Light Emitting Diode Irradiation  

Microsoft Academic Search

Plant growth under light emitting diodes (LEDs) was investigated to determine if LEDs would be useful to provide radiant energy for two plant processes, photosynthesis and photomorphogenesis. Photosynthesis of tomato (Lycopersicon esculentum L.) and Kudzu (Pueraria lobata (Willd) Ohwi.) was measured using photons from LEDs to answer the following: (1) Are leaves able to use red LED light for photosynthesis?

Daniel John Tennessen

1994-01-01

269

Light Measurements in Plant Growth Investigations  

Microsoft Academic Search

PROF. HEATH raises the fundamental question of the purpose of making light measurements, and I am happy to give my point of view. I think that it will eventually be possible to predict the growth rates of plants from measurements on their environments, given sufficient understanding of the principles behind the interactions between plant and environment. The models will have

K. J. McCree

1966-01-01

270

Plant growth: roots in the cell cycle.  

PubMed

Overexpression in transgenic plants of a B-type cyclin--thought to regulate cell-cycle progression to mitosis--causes structures such as roots to grow faster than normal, indicating that the rate of cell division may be a constraint on plant growth. PMID:8805285

Doonan, J

1996-07-01

271

Rotary plant growth accelerating apparatus. [weightlessness  

NASA Technical Reports Server (NTRS)

Rotary plant growth accelerating apparatus for increasing plant yields by effectively removing the growing plants from the constraints of gravity and increasing the plant yield per unit of space is described. The apparatus is comprised of cylindrical plant beds supported radially removed from a primary axis of rotation, with each plant bed being driven about its own secondary axis of rotation and simultaneously moved in a planetary path about the primary axis of rotation. Each plant bed is formed by an apertured outer cylinder, a perforated inner cylinder positioned coaxially, and rooting media disposed in the space between. A rotatable manifold distributes liquid nutrients and water to the rooting media through the perforations in the inner cylinders as the plant beds are continuously rotated by suitable drive means.

Dedolph, R. D. (inventor)

1975-01-01

272

The effect of enhanced ultraviolet-B radiation on germination and seedling development of plant species occurring in a dune grassland ecosystem  

Microsoft Academic Search

The germination of seeds of seven plant species occurring in a dune grassland vegetation of the Netherlands, was studied at four levels of UV-B radiation simulating unto 45% stratospheric ozone reduction during April. With the exception of seeds of Senecio jacobaea, germination of the dune grassland species was not affected by enhanced UV-B irradiance. Although a clear UV-B fluence-response relationship

Marcel Tosserams; Esther Bolink; Jelte Rozema

1997-01-01

273

Effects of seven pure flavonoids from mosses on germination and growth of Tortula muralis HEDW (Bryophyta) and Raphanus sativus L (Magnoliophyta).  

PubMed

Dried mosses (five moss species) were progressively extracted and subjected to a four-step Craig distribution. Seven pure flavonoids were isolated and identified. The flavonoids were the flavones apigenin, apigenin-7-O-triglycoside, lucenin-2, luteolin-7-O-neohesperidoside, saponarine and vitexin; and the biflavonoid bartramiaflavone and they were submitted to biological tests. The tests were performed in vitro on spore germination and protonemal growth of the moss Tortula muralis and on seed germination and root growth of Raphanus sativus. Flavonoids caused a decrease in the percentage of spore germination, protonemal development and root growth. In addition they caused morphological alterations, such as forked tips, swollen apices, rounded cells and early formation of brood cells in the protonemata. Data were discussed in relation to the presence of allelochemicals in mosses. PMID:12591270

Basile, Adriana; Sorbo, Sergio; Lpez-Sez, Jos Antonio; Castaldo Cobianchi, Rosa

2003-04-01

274

Allelopathic effect of four weed species extracts on germination, growth and protein in different varieties of Glycine max (L.) Merrill.  

PubMed

Allelopathic effect of Ageratum conyzoides L., Cynodon dactylon (L.) Pers., Parthenium hysterophorus L., and Solanum nigrum L. were examined on seed germination, seedling growth, total protein content and protein profile on Ankur, Bhatt, Bragg, PK -416, PS-1042 and Shilajeet varieties of soybean (Glycine max (L) Merill). Aqueous extracts of weeds (10% w/v) showed both inhibitory and stimulatory influence on percent seed germination and seedling growth in different varieties of soybean. On the basis of per cent reduction in different parameters, the variety Bragg and PS-1042, and Shilajeet were resistant and susceptible respectively to different weed extracts, and among weed extracts, S. nigrum was most effective followed by P. hysterophorus compared to others. The total protein content (mg/g f wt.) in different varieties was increased with all the weed extracts except Bragg with C. dactylon and P. hysterophorus, PS-1042 with A. conyzoides and Shilajeet with C. dactylon, in which it was decreased. The protein banding pattern in different varieties not only differ between control and treatments but also among treatments. The order of susceptibility of different varieties with different weed extracts followed the order: Ankur > PK-416 > Bhatt > Shilajeet > Bragg and > PS-1042. PMID:17402252

Verma, Monica; Rao, P B

2006-07-01

275

Assessment of the allelopathic potential of Juniperus ashei on germination and growth of Bouteloua curtipendula.  

PubMed

Potential allelopathic compounds of Juniperus ashei Buchh. (Ashe juniper) and their effect on a native grass were determined in laboratory and field studies. Solid-phase microextraction and gas chromatography/mass spectrometry were used to determine if monoterpenes found in the essential oils of J. ashei are released in leaf and litter leachate, as well as volatilized from leaf tissue. Camphor, bornyl acetate, and limonene were found in leaf and fresh litter leachates; however, degraded litter did not contain any of these compounds. Camphor was the most common potentially allelopathic compound found in J. ashei leaf and litter leachate and in volatiles from leaf tissue. The effects of leaf and litter tissue on the germination of Bouteloua curtipendula (Michx.) Torr. (side-oats grama) was tested by using the "sandwich agar method". The highest germination of B. curtipendula (29.6%) occurred in the control, which was significantly higher than fresh litter (13.2%) and degraded litter (16.2%). The lowest germination (6.2%) occurred with J. ashei leaves. In the field experiment, aboveground dry mass of B. curtipendula was evaluated in relation to position within the canopy and intercanopy of J. ashei adult trees when light and water were held constant across locations. Aboveground dry mass of B. curtipendula was significantly greater in the intercanopies of J. ashei (163.7 g m(2)) compared to the dry mass in the understory (44.8 g m(2)) and dripline (44.5 g m(2)), suggesting some negative influence by J. ashei. Chemical analyses indicate that monoterpenes are released through leaching and volatilization from J. ashei, and germination and field studies suggest that these compounds inhibit B. curtipendula. PMID:19153797

Young, G P; Bush, J K

2009-01-01

276

Plant Growth Modelling and Applications: The Increasing Importance of Plant Architecture in Growth Models  

PubMed Central

Background Modelling plant growth allows us to test hypotheses and carry out virtual experiments concerning plant growth processes that could otherwise take years in field conditions. The visualization of growth simulations allows us to see directly and vividly the outcome of a given model and provides us with an instructive tool useful for agronomists and foresters, as well as for teaching. Functionalstructural (FS) plant growth models are nowadays particularly important for integrating biological processes with environmental conditions in 3-D virtual plants, and provide the basis for more advanced research in plant sciences. Scope In this viewpoint paper, we ask the following questions. Are we modelling the correct processes that drive plant growth, and is growth driven mostly by sink or source activity? In current models, is the importance of soil resources (nutrients, water, temperature and their interaction with meristematic activity) considered adequately? Do classic models account for architectural adjustment as well as integrating the fundamental principles of development? Whilst answering these questions with the available data in the literature, we put forward the opinion that plant architecture and sink activity must be pushed to the centre of plant growth models. In natural conditions, sinks will more often drive growth than source activity, because sink activity is often controlled by finite soil resources or developmental constraints. PMA06 This viewpoint paper also serves as an introduction to this Special Issue devoted to plant growth modelling, which includes new research covering areas stretching from cell growth to biomechanics. All papers were presented at the Second International Symposium on Plant Growth Modeling, Simulation, Visualization and Applications (PMA06), held in Beijing, China, from 1317 November, 2006. Although a large number of papers are devoted to FS models of agricultural and forest crop species, physiological and genetic processes have recently been included and point the way to a new direction in plant modelling research. PMID:18387970

Fourcaud, Thierry; Zhang, Xiaopeng; Stokes, Alexia; Lambers, Hans; Korner, Christian

2008-01-01

277

Effects of triclosan on seed germination and seedling development of three wetland plants: Sesbania herbacea, Eclipta prostrata, and Bidens frondosa.  

PubMed

Three wetland macrophytes, Sesbania herbacea, Bidens frondosa, and Eclipta prostrata, were exposed (0.4-1,000-ppb nominal concentrations) to the antimicrobial triclosan for 28 d in a flow-through system. Sesbania herbacea had decreased seed germination at the 100-ppb exposure level at days 7, 14, and 21, and B. frondosa germination was reduced at the 1,000-ppb exposure level at day 7. Eclipta prostrata germination was unaffected. Seedling effects monitored were total fresh weight, shoot and root fresh weights, root length, and root surface area. Root metrics were most affected by exposure. Total root length was diminished at all exposure levels in S. herbacea and B. frondosa and at the 10-ppb and higher concentrations for E. prostrata. Root surface area decreased at all exposure levels in B. frondosa and at the 10-ppb level and above in S. herbacea and E. prostrata. Root and shoot bioconcentration factors (BCFs) were estimated for S. herbacea and B. frondosa. While BCFs were low in shoots of both species and roots of S. herbacea (<10), they were elevated in B. frondosa roots (53-101). Methyl-triclosan was formed in the system and accumulated in shoot and root tissues of S. herbacea to concentrations that exceeded those of the parent compound. However, methyl-triclosan was nontoxic in an Arabidopsis thaliana enoyl-acyl carrier protein reductase (the putative enzymatic target of triclosan) assay and did not appear to contribute to the effects of exposure. Two of the three plant species assessed exhibited reduced root systems at environmentally relevant concentrations, raising the concern that wetland plant performance could be compromised in constructed wetlands receiving wastewater treatment plant discharges. PMID:19653736

Stevens, Kevin J; Kim, Seon-Young; Adhikari, Sajag; Vadapalli, Vatsala; Venables, Barney J

2009-12-01

278

Progesterone: its occurrence in plants and involvement in plant growth.  

PubMed

Progesterone is a mammalian gonadal hormone. In the current study, we identified and quantified progesterone in a range of higher plants by using GC-MS and examined its effects on the vegetative growth of plants. The growth of Arabidopsis (Arabidopsis thaliana) seedlings was promoted by progesterone at low concentrations but suppressed at higher concentrations under both light and dark growth conditions. The growth of the gibberellin-deficient mutant lh of pea (Pisum sativum) was also promoted by progesterone. An earlier study demonstrated that progesterone binds to MEMBRANE STEROID BINDING PROTEIN 1 (MSBP1) of Arabidopsis. In this work, we cloned the homologous genes of Arabidopsis, MSBP2 and STEROID BINDING PROTEIN (SBP), as well as of rice (Oryza sativa), OsMSBP1, OsMSBP2 and OsSBP and examined their expression in plant tissues. All of these genes, except OsMSBP1, were expressed abundantly in plant tissues. The roles of progesterone in plant growth were also discussed. PMID:17512025

Iino, Mayumi; Nomura, Takahito; Tamaki, Yuji; Yamada, Yumiko; Yoneyama, Koichi; Takeuchi, Yasutomo; Mori, Masaki; Asami, Tadao; Nakano, Takeshi; Yokota, Takao

2007-06-01

279

Plant germination and production of callus from the yellow hornpoppy (Glaucium flavum): the first stage of micropropagation.  

PubMed

The yellow hornpoppy, Glaucium flavum Cr. (Fam. Papaveraceae) is a perennial herb, distributed in the Mediterranean region, including Egypt. The plant contains many benzyl isoquinoline alkaloids from the aporphine type such as glaucine, isoboldine, 1-chelidonine, 1-norchelidonine and 3-O-methylarterenol, making it to display various medicinal activities including antitussive, anticancer, antioxidant, antimicrobial, antiviral, hypoglycemic, analgesic, antipyretic, bronchodilator and anti-inflammatory effects. The plant is now rare and endangered in the Egyptian flora due to urban sprawl. The present study looks into Glaucium flavum seeds' in vitro germination as well as the ability of the explants taken from the growing seedlings to form stable callus lines in order to enable micropropagation as a way to save the rare plant. The study also scans the production of different medicinally valuable alkaloids, particularly glaucine, in produced callus. PMID:25272947

Mohamed, M E; Arafa, A M; Soliman, S S; Eldahmy, S I

2014-09-01

280

Effect of synthetic detergents on germination of fern spores  

SciTech Connect

Synthetic detergents constitute one of the most important water pollutants by contaminating the lakes and rivers through domestic and industrial use. Considerable information is now available for the adverse effects of detergents an aquatic fauna including fish, algae, and higher aquatic plants. Marked inhibition of germination in orchids and brinjals and of seedlings growth in raddish suggest that rapidly growing systems could be sensitive to detergent polluted water. The present study of the effect of linear alkyl benzene sulphonate on germination of the spores of a fern, Diplazium esculentum aims at the understanding of the effects of water pollution on pteridophytes and the development of spore germination assay for phytoxicity evaluation.

Devi, Y.; Devi, S.

1986-12-01

281

Regulation of Plant Morphology by Growth Retardants  

PubMed Central

The effects of the growth retardants tetcyclacis, a norbornenodiazetine, and LAB 150 978, a dioxanylalkenyl triazole, on seedling growth and endogenous levels of phytohormone-like substances in Glycine max L. cv Maple Arrow were studied. The levels of phytohormone-like substances in the root and in the various shoot tissues were analyzed by immunoassay. After seed treatment with both compounds, shoot growth was reduced more intensively than root growth. Both compounds decreased, on a fresh weight basis, the amount of various immunoreactive gibberellins when compared with the levels in control plants, especially in the shoot tip. Likewise, the growth retardants lowered the levels of abscisic acid-like material, particularly in the primary leaf, the epicotyl and the root. In contrast, the levels of trans-zeatin-riboside and dihydrozeatin-riboside-type cytokinins were considerably elevated by the growth retardants, mainly in the primary leaf, epicotyl, and hypocotyl. On the other hand the level of isopentenyladenosine-like material was less influenced. In general, the immunoreactive 3-indoleacetic acid content in the different plant parts was changed only slightly. It is assumed that besides their effect on gibberellin content both compounds interfere directly or indirectly with the regulation of the endogenous levels of abscisic acid and cytokinins. This might be seen as an additional mode of action of growth retardants explaining some side effects on developmental processes of treated plants, e.g. delayed senescence and enhanced chlorophyll concentration in the leaves. PMID:16665554

Grossmann, Klaus; Kwiatkowski, Jacek; Siebecker, Heinrich; Jung, Johannes

1987-01-01

282

Temperature-dependent growth and emergence of functional leaves: an adaptive mechanism in the seedlings of the western Himalayan plant Podophyllum hexandrum  

Microsoft Academic Search

As an adaptive mechanism, hypocotyl dormancy delays emergence of functional leaf until favorable season of growth in Podophyllum hexandrum, an endangered medicinal plant of the western Himalayas. However, upon exposure of the freshly germinated seedlings to favorable\\u000a temperature (25C), functional leaves emerged within 20days. Therefore, we examined regulation mechanisms of growth and development\\u000a of this alpine plant by temperature under

Rekha Kushwaha; Subedar Pandey; Sanjoy Chanda; Amita Bhattacharya; Paramvir Singh Ahuja

2008-01-01

283

Enhanced plant growth by siderophores produced by plant growth-promoting rhizobacteria  

Microsoft Academic Search

Specific strains of the Pseudomonas fluorescens-putida group have recently been used as seed inoculants on crop plants to promote growth and increase yields. These pseudomonads, termed plant growth-promoting rhizobacteria (PGPR), rapidly colonize plant roots of potato, sugar beet and radish, and cause statistically significant yield increases up to 144% in field tests1-5. These results prompted us to investigate the mechanism

Joseph W. Kloepper; John Leong; Martin Teintze; Milton N. Schroth

1980-01-01

284

How the Plant Growth-Promoting Bacterium Azospirillum Promotes Plant GrowthA Critical Assessment  

Microsoft Academic Search

During the last 35 years of studies of Azospirillumplant interaction, over 20 proposals were suggested for the mechanism of action by which Azospirillum spp., the most intensively studied plant growth-promoting bacteria, enhances plant growth. The proposals include a single phytohormone activity, multiple phytohormones, nitrogen fixation, assortments of small-sized molecules and enzymes, enhanced membrane activity, proliferation of the root system, enhanced

Yoav Bashan; Luz E. de-Bashan

2010-01-01

285

Lunar base agriculture: Soils for plant growth  

NASA Technical Reports Server (NTRS)

This work provides information on research and experimentation concerning various aspects of food production in space and particularly on the moon. Options for human settlement of the moon and Mars and strategies for a lunar base are discussed. The lunar environment, including the mineralogical and chemical properties of lunar regolith are investigated and chemical and physical considerations for a lunar-derived soil are considered. It is noted that biological considerations for such a soil include controlled-environment crop production, both hydroponic and lunar regolith-based; microorganisms and the growth of higher plants in lunar-derived soils; and the role of microbes to condition lunar regolith for plant cultivation. Current research in the controlled ecological life support system (CELSS) project is presented in detail and future research areas, such as the growth of higher research plants in CELSS are considered. Optimum plant and microbiological considerations for lunar derived soils are examined.

Ming, Douglas W. (editor); Henninger, Donald L. (editor)

1989-01-01

286

Dynamical scaling analysis of plant callus growth  

NASA Astrophysics Data System (ADS)

We present experimental results for the dynamical scaling properties of the development of plant calli. We have assayed two different species of plant calli, Brassica oleracea and Brassica rapa, under different growth conditions, and show that their dynamical scalings share a universality class. From a theoretical point of view, we introduce a scaling hypothesis for systems whose size evolves in time. We expect our work to be relevant for the understanding and characterization of other systems that undergo growth due to cell division and differentiation, such as, for example, tumor development.

Galeano, J.; Buceta, J.; Juarez, K.; Pumario, B.; de la Torre, J.; Iriondo, J. M.

2003-07-01

287

Plant growth control by regulated lighting conditions  

Microsoft Academic Search

In this study, both a mercury free lamp and a conventional lamp were used for growing lettuce, which means that the R\\/FR environment was changed for one plant growth interval between R\\/FR>3.0 and R\\/FR<1.0. From the experiments, the growth speed was faster and the leaf shape and leaf area were larger than growing the lettuce under a single lamp.

T. Okame; K. Murakami; N. Saito; S. Kosaka; H. Murase

2002-01-01

288

Light Measurements in Plant Growth Investigations  

Microsoft Academic Search

THE procedure suggested by K. J. McCree1 under the above heading would only be of use if it were intended to estimate plant growth from the time-integrated values of the transformed light measurements, and in view of the many assumptions involved it would then seem more sensible to measure the growth directly. He implies that the object of measuring daylight

O. V. S. Heath

1966-01-01

289

Proteomic analyses of apoplastic proteins from germinating Arabidopsis thaliana pollen  

PubMed Central

Pollen grains play important roles in the reproductive processes of flowering plants. The roles of apoplastic proteins in pollen germination and in pollen tube growth are comparatively less well understood. To investigate the functions of apoplastic proteins in pollen germination, the global apoplastic proteins of mature and germinated Arabidopsis thaliana pollen grains were prepared for differential analyses by using 2-dimensional fluorescence difference gel electrophoresis (2-D DIGE) saturation labeling techniques. One hundred and three proteins differentially expressed (p value ? 0.01) in pollen germinated for 6h compare with un-germination mature pollen, and 98 spots, which represented 71 proteins, were identified by LC-MS/MS. By bioinformatics analysis, 50 proteins were identified as secreted proteins. These proteins were mainly involved in cell wall modification and remodeling, protein metabolism and signal transduction. Three of the differentially expressed proteins were randomly selected to determine their subcellular localizations by transiently expressing YFP fusion proteins. The results of subcellular localization were identical with the bioinformatics prediction. Based on these data, we proposed a model for apoplastic proteins functioning in pollen germination and pollen tube growth. These results will lead to a better understanding of the mechanisms of pollen germination and pollen tube growth. PMID:21798377

Ge, Weina; Song, Yun; Zhang, Cuijun; Zhang, Yafang; Burlingame, Alma L.; Guo, Yi

2011-01-01

290

Thorium uptake by wheat at different stages of plant growth  

Microsoft Academic Search

Data on biogeochemistry of thorium are rather limited. So far little is known about toxic effects of small amounts of the radionuclide on higher plants. In this study the uptake of thorium by wheat seedlings was measured by greenhouse experiments. Germination of wheat seeds for 6 days in the presence of thorium resulted in accumulation of the metal in all

I. Shtangeeva; S. Ayrault; J. Jain

2005-01-01

291

Embryo growth, testa permeability, and endosperm weakening are major targets for the environmentally regulated inhibition of Lepidium sativum seed germination by myrigalone A.  

PubMed

Myrigalone A (MyA) is a rare flavonoid in fruit leachates of Myrica gale, a deciduous shrub adapted to flood-prone habitats. As a putative allelochemical it inhibits seed germination and seedling growth. Using Lepidium sativum as a model target species, experiments were conducted to investigate how environmental cues modulate MyA's interference with key processes of seed germination. Time course analyses of L. sativum testa and endosperm rupture under different light conditions and water potentials were combined with quantifying testa permeability, endosperm weakening, tissue-specific gibberellin (GA) and abscisic acid (ABA) contents, as well as embryo growth and apoplastic superoxide production important for cell expansion growth. Lepidium sativum testa permeability and early water uptake by imbibition is enhanced by MyA. During late germination, MyA inhibits endosperm weakening and embryo growth, both processes required for endosperm rupture. Inhibition of embryo cell expansion by MyA depends on environmental cues, which is evident from the light-modulated severity of the MyA-mediated inhibition of apoplastic superoxide accumulation. Several important key weakening and growth processes during early and late germination are targets for MyA. These effects are modulated by light conditions and ambient water potential. It is speculated that MyA is a soil seed bank-destroying allelochemical that secures the persistence of M. gale in its flood-prone environment. PMID:22821938

Voegele, Antje; Graeber, Kai; Oracz, Krystyna; Tarkowsk, Danue; Jacquemoud, Dominique; Ture?kov, Veronika; Urbanov, Terezie; Strnad, Miroslav; Leubner-Metzger, Gerhard

2012-09-01

292

Ambient has Become Strained. Identification of Acacia dealbata Link Volatiles Interfering with Germination and Early Growth of Native Species.  

PubMed

Acacia dealbata Link is a widespread invader in Mediterranean type ecosystems, and traits promoting its invasiveness are currently under investigation. Due to the dense atmosphere below its canopy, we hypothesized that volatile organic compounds (VOCs) released from flowers, leaves, litter, or a mixture of treatments exert inhibitory effects on the natives Trifolium subterraneum, Lolium multiflorum, Medicago sativa, and also on its own seeds. We reported that VOCs from flowers significantly reduced germination in L. multiflorum and A. dealbata; moreover, root length, stem length, aboveground and belowground biomass were also reduced in all species studied. Volatile organic compounds from flowers and the mixture also increased significantly malondialdehyde content in T. subterraneum and L. multiflorum. The effects of VOCs on antioxidant enzymatic activities were species dependent. Flowers enhanced peroxidase but decreased superoxide dismutase activity in T. subterraneum. In contrast, VOCs released from leaves increased the activity of superoxide dismutase in L. multiflorum. GC/MS analyses revealed 27 VOCs in the volatile fraction from flowers, 12 of which were exclusive to this fraction. Within them, heptadecadiene, n-nonadecane, n-tricosane, and octadecene represent 62% of the fraction. We present evidence that the VOCs released from A. dealbata flowers strongly inhibited germination and seedling growth of selected species, and mainly on its own seedlings. As far as we know, this is the first evidence of phytotoxicity induced by VOCs in invasive species belonging to the Acacia genus. PMID:25260655

Souza-Alonso, Pablo; Gonzlez, Lus; Cavaleiro, Carlos

2014-09-01

293

Dredged Illinois River Sediments: Plant Growth and Metal Uptake  

USGS Publications Warehouse

Sedimentation of the Illinois River in central Illinois has greatly diminished the utility and ecological value of the Peoria Lakes reach of the river. Consequently, a large dredging project has been proposed to improve its wildlife habitat and recreation potential, but disposal of the dredged sediment presents a challenge. Land placement is an attractive option. Previous work in Illinois has demonstrated that sediments are potentially capable of supporting agronomic crops due to their high natural fertility and water holding capacity. However, Illinois River sediments have elevated levels of heavy metals, which may be important if they are used as garden or agricultural soil. A greenhouse experiment was conducted to determine if these sediments could serve as a plant growth medium. A secondary objective was to determine if plants grown on sediments accumulated significant heavy metal concentrations. Our results indicated that lettuce (Lactuca sativa L.), barley (Hordeum vulgare L.), radish (Raphanus sativus L.), tomato (Lycopersicon lycopersicum L.), and snap bean (Phaseolus vulagaris L. var. humillis) grown in sediment and a reference topsoil did not show significant or consistent differences in germination or yields. In addition, there was not a consistent statistically significant difference in metal content among tomatoes grown in sediments, topsoil, or grown locally in gardens. In the other plants grown on sediments, while Cd and Cu in all cases and As in lettuce and snap bean were elevated, levels were below those considered excessive. Results indicate that properly managed, these relatively uncontaminated calcareous sediments can make productive soils and that metal uptake of plants grown in these sediments is generally not a concern.

Darmody, R. G.; Marlin, J. C.; Talbott, J.; Green, R. A.; Brewer, E. F.; Stohr, C.

2004-01-01

294

Rhizoctonia wilt suppression of brinjal (Solanum melongena L) and plant growth activity by Bacillus BS2.  

PubMed

An antibiotic-producing and hydrogen-cyanide-producing rhizobacteria strain Bacillus BS2 showed a wide range of antifungal activity against many Fusarium sp. and brinjal wilt disease pathogen Rhizoctonia solani. Seed bacterization with the strain BS2 promoted seed germination and plant growth in leguminous plants Phaseolus vulgaris and non-leguminous plants Solanum melongena L, Brassica oleracea var. capitata, B. oleraceae var. gongylodes and Lycopersicon esculentum Mill in terms of relative growth rate, shoot height, root length, total biomass production and total chlorophyll content of leaves. Yield of bacterized plants were increased by 10 to 49% compared to uninoculated control plants. Brinjal sapling raised through seed bacterization by the strain BS2 showed a significantly reduced wilt syndrome of brinjal caused by Rhizoctonia solani. Control of wilt disease by the bacterium was clue to the production of antibiotic-like substances, whereas plant growth-promotion was due to the activity of hydrogen cyanide. Root colonization study confirmed that the introduced bacteria colonized the roots and occupied 23-25% of total aerobic bacteria, which was confirmed using dual antibiotic (nalidixic acid and streptomycin sulphate) resistant mutant strain. The results obtained through this investigation suggested the potentiality of the strain BS2 to be used as a plant growth promoter and suppressor of wilt pathogen. PMID:15266911

Boruah, H P Deka; Kumar, B S Dileep

2003-06-01

295

The Effects of Moist-Heat Treatments and Stratification on Germination of Prairie Plant Seeds  

Microsoft Academic Search

Germination of Silphium terebinthenaceum was enhanced by a post-stratification most-heat treatment at 80C. Tested seeds of four other perennial herbs common to midwestern prairies (Andropogon scoparius, Sorghastrum nutans, Eryngium yuccifolium, and Solidago rigida) showed little adverse or beneficial effects of the heat treatment. Heat treatments alone had little effect on the seeds; the length of stratification periods necessary to effect

John E. Stuurwold

1972-01-01

296

Male-female crosstalk during pollen germination, tube growth and guidance, and double fertilization.  

PubMed

Sperm cells of flowering plants are non-motile and thus require transportation to the egg apparatus via the pollen tube to execute double fertilization. During its journey, the pollen tube interacts with various sporophytic cell types that support its growth and guide it towards the surface of the ovule. The final steps of tube guidance and sperm delivery are controlled by the cells of the female gametophyte. During fertilization, cell-cell communication events take place to achieve and maximize reproductive success. Additional layers of crosstalk exist, including self-recognition and specialized processes to prevent self-fertilization and consequent inbreeding. In this review, we focus on intercellular communication between the pollen grain/pollen tube including the sperm cells with the various sporophytic maternal tissues and the cells of the female gametophyte. Polymorphic-secreted peptides and small proteins, especially those belonging to various subclasses of small cysteine-rich proteins (CRPs), reactive oxygen species (ROS)/NO signaling, and the second messenger Ca(2+), play center stage in most of these processes. PMID:23571489

Dresselhaus, Thomas; Franklin-Tong, Noni

2013-07-01

297

The biosurfactant viscosin produced by Pseudomonas fluorescens SBW25 aids spreading motility and plant growth promotion.  

PubMed

Food security depends on enhancing production and reducing loss to pests and pathogens. A promising alternative to agrochemicals is the use of plant growth-promoting rhizobacteria (PGPR), which are commonly associated with many, if not all, plant species. However, exploiting the benefits of PGPRs requires knowledge of bacterial function and an in-depth understanding of plant-bacteria associations. Motility is important for colonization efficiency and microbial fitness in the plant environment, but the mechanisms employed by bacteria on and around plants are not well understood. We describe and investigate an atypical mode of motility in Pseudomonas fluorescens SBW25 that was revealed only after flagellum production was eliminated by deletion of the master regulator fleQ. Our results suggest that this 'spidery spreading' is a type of surface motility. Transposon mutagenesis of SBW25?fleQ (SBW25Q) produced mutants, defective in viscosin production, and surface spreading was also abolished. Genetic analysis indicated growth-dependency, production of viscosin, and several potential regulatory and secretory systems involved in the spidery spreading phenotype. Moreover, viscosin both increases efficiency of surface spreading over the plant root and protects germinating seedlings in soil infected with the plant pathogen Pythium. Thus, viscosin could be a useful target for biotechnological development of plant growth promotion agents. PMID:24684210

Alsohim, Abdullah S; Taylor, Tiffany B; Barrett, Glyn A; Gallie, Jenna; Zhang, Xue-Xian; Altamirano-Junqueira, Astrid E; Johnson, Louise J; Rainey, Paul B; Jackson, Robert W

2014-07-01

298

How do cell walls regulate plant growth?  

Microsoft Academic Search

The cell wall of growing plant tissues has frequently been interpreted in terms of inextensible cellulose microfibrils 'tethered' by hemicellulose polymers at- tached to the microfibril surface by hydrogen bonds, with growth occurring when tethers are broken or 'peeled' off the microfibril surface by expansins. This has sometimes been described as the 'sticky network' model. In this paper, a number

David Stuart Thompson

2005-01-01

299

Static Magnetic Field and Plant Growth  

NASA Astrophysics Data System (ADS)

In the conditions of stable existence of Static Magnetic Field (SMF) the growth processes of some plants' (chickpeas, beans and lentils) seeds have been investigated in different temperatures of microenvironment. It has been established that the rate of the plant growths is affected (speeded up) by SMF that is intimately related to environmental temperature, any other environmental parameters (humidity, illumination, soil chemical state, etc) being under control. At the same time, the highest rate of growth has been observed in beans at a range of 30, 0 +/- 2, 0 C. Special experiments and analyses of the data obtained, testified that the plants roots occurred the main target for SMF to be affected to get increasing rate. In order to standardize experimental conditions, the SMF have been created by magnetic bars of the intensity of B, equal that of the Earth at a distance of 23 cm from a pole of a bar magnet on the line passing along the both of its poles. Taking as a basis the results, it may be concluded that SMF can affect plant growth process, being regarded as an environmental factor of ecological importance.

Maharramov, Akif A.

2007-04-01

300

Effect of two species of cyanobacteria as biofertilizers on some metabolic activities, growth, and yield of pea plant  

Microsoft Academic Search

Two cyanobacterial species (Nostoc entophytum and Oscillatoria angustissima) were tested as biofertilizers, substituting the normally used chemical fertilizer, for pea plant. Inoculation of soil with\\u000a a suspension of each species or a combination of the two species significantly increased the germination percentage and stimulated\\u000a the other measured growth parameters and photosynthetic pigment fractions of pea. However, the soil inoculation with

Mohamed Elanwar H. Osman; Mostafa M. El-Sheekh; Amal H. El-Naggar; Saly F. Gheda

2010-01-01

301

Effect of bacterial population density on germination wheat seeds and dynamics of simple artificial ecosystems  

NASA Astrophysics Data System (ADS)

Effect of the size of rhizospheric bacterial populations on germination of seeds and development of simple terrestrial "wheat plants - rhizospheric microorganisms - artificial soil" and "wheat plants - artificial soil" systems has been studied. Experiments demonstrated that within specify ranges in the inoculate, the rhizospheric bacteria are capable of increasing the yield of germinated seeds and stimulate the growth of plantlets. Germination of seeds inoculated with bacteria was either stimulated, or inhibited or remained at control levels depending on the amount of bacteria. Plant biomass growth and total photoassimilation has been found to depend on the amount of bacteria on the plant roots: the higher the amount of bacteria on plant roots, the smaller is the biomass of plants but the total photoassimilation is, higher. Thus, depending on the amount of bacteria on the roots of plants the system either increases the biomass of plants or increases the total photoassimilation, i.e. "pumps" carbon through itself involving bacteria.

Somova, L. A.; Pechurkin, N. S.; Sarangova, A. B.; Pisman, T. I.

302

The transcriptomes of dormant leafy spurge seeds under alternating temperature are differentially affected by a germination-enhancing pretreatment.  

PubMed

Seed dormancy is an important stage in the life cycle of many non-domesticated plants, often characterized by the temporary failure to germinate under conditions that normally favor the process. Pre-treating dormant imbibed seeds at a constant temperate accelerated germination of leafy spurge seeds under alternating temperatures. However, dormant seeds will also germinate without a pre-treatment, albeit at a much slower rate, which gives rise to longer periods of imbibition before germination. Transcriptome analyses on seeds exposed to prolonged imbibition highlighted pathways associated with phenylpropanoid biosynthesis and interacting networks of genes involved in plant defense. In addition to the many pathways associated with phenylpropanoid biosynthesis enriched with down-regulated genes upon germination, there were also numerous pathways enriched with up-regulated genes associated with energy metabolism, such as glycolysis. Transcriptome data further suggest that metabolism and signaling by the plant hormones ethylene, gibberellin, and abscisic acid are involved in the developmental transition from dormancy to germination. More specifically, sub-network enrichment analysis identified ABI3 as a central hub of a sub-network at germination including several down-regulated genes such as DELLA (i.e., RGL2), which represses gibberellin signaling processes required for germination. The 595-fold increase in the expression of ACC oxidase (ACO4) at germination also suggests an important role for ethylene biosynthesis in germinating leafy surge seeds. Furthermore, the 10-578-fold difference in expression of many genes such as HY5 and Histone H3 between two populations at germination, which were treated with and without a constant temperature germination-enhancing pretreatment, revealed disparate impacts on various biosynthetic, growth, signaling, and response processes. Overall, our results indicate a constant temperature pretreatment (20C for 21d) is not required for germination of leafy spurge seeds at an alternating temperature. However, the presence or absence of the pretreatment does affect the rate of germination and the germination transcriptional programs. PMID:23261266

Foley, Michael E; Chao, Wun S; Horvath, David P; Do?ramaci, Mnevver; Anderson, James V

2013-04-15

303

In Vitro Propagation by Asymbiotic Seed Germination and 1,1Diphenyl2-picrylhydrazyl (DPPH) Radical Scavenging Activity Studies of Tissue Culture Raised Plants of Three Medicinally Important Species of Dendrobium  

Microsoft Academic Search

A simple and efficient plant propagation system has been developed by asymbiotic germination of seeds in three medicinally important Dendrobium species, namely, Dendrobium tosaense, Dendrobium moniliforme, and Dendrobium linawianum. Plants obtained from natural habitats were grown in the greenhouse. The flowers were hand pollinated. Seeds of the capsules derived after 12 weeks of hand-pollination germinated asymbiotically (5074%) on half strength

Shu-Fung Lo; Satish Manohar Nalawade; Vanisree Mulabagal; Susan Matthew; Chung-Li Chen; Chao-Lin Kuo; Hsin-Sheng Tsay

2004-01-01

304

Growth and N Allocation in Rice Plants under CO2 Enrichment.  

PubMed Central

The effects of CO2 enrichment on growth and N allocation of rice (Oryza sativa L.) were examined. The plants were grown hydroponically in growth chambers with a 14-h photoperiod (1000 [mu]mol quanta m-2 s-1) and a day/night temperature of 25/20[deg]C. From the 28th to 70th d after germination, the plants were exposed to two CO2 partial pressures, namely 36 and 100 Pa. The CO2 enrichment increased the final biomass, but this was caused by a stimulation of the growth rate during the first week of the exposure to elevated CO2 partial pressures. The disappearance of the initial stimulation of the growth rate was associated with a decreased leaf area ratio. Furthermore, CO2 enrichment decreased the investment of N in the leaf blades, whereas the N allocation into the leaf sheaths and roots increased. Thus, the decrease in leaf N content by CO2 enrichment was not due to dilution of N caused by a relative increase in the plant biomass but was due to the change in N allocation at the whole-plant level. We conclude that the growth responses of rice to CO2 enrichment are mainly controlled by leaf area expansion and N allocation into leaf blades at the whole-plant level. PMID:12223800

Makino, A.; Harada, M.; Sato, T.; Nakano, H.; Mae, T.

1997-01-01

305

Repression of AUXIN RESPONSE FACTOR10 by microRNA160 is critical for seed germination and  

E-print Network

Repression of AUXIN RESPONSE FACTOR10 by microRNA160 is critical for seed germination and post and ABA pathways. Keywords: microRNA, seed germination, ARF10, miR160, ABA, auxin. Introduction micro during many stages of plant growth development. ARF10, ARF16 and ARF17 are targeted by microRNA160 (mi

Montgomery, Tai

306

Faster plant growth in a safe, economical way  

E-print Network

- 1 - Faster plant growth in a safe, economical way April 3, 2012 Good science and good business: synthesizing plant metabolite creates an economical growth treatment Biagro Western Sales, Inc., was founded plant metabolite that, when applied to plants, speeds crop emergence, increases growth rates and yields

307

UNIVERSITY OF MISSOURI -COLUMBIA PLANT GROWTH FACILITIES MASTER PLAN  

E-print Network

UNIVERSITY OF MISSOURI - COLUMBIA PLANT GROWTH FACILITIES MASTER PLAN PROJECT NO 400771 July 3 - COLUMBIA PLANT GROWTH FACILITIES MASTER PLAN 2 1.1 Executive Summary Plant Sciences have a fundamental role and continued success of plant growth based research on campus has led to the efforts of this master plan

Noble, James S.

308

Seed germination, root elongation, root-tip mitosis, and micronucleus induction of five crop plants exposed to chromium in fluvo-aquic soil.  

PubMed

The present study aimed to determine the toxic effects of chromium (Cr) on cabbage (Brassica oleracea), cucumber (Cucumis sativus), lettuce (Lactuca sativa), wheat (Triticum aestivum), and corn (Zea mays), and identify the sensitive plant species and appropriate bioassays for potential use in phytotoxicity assessment of Cr in soil. Results showed that seed germination might not be a sensitive assay for assessing Cr toxicity because at most of the Cr levels there were no toxic effects. Root elongation was more sensitive to Cr than seed germination. The lowest concentration of adverse effect (LOAEC) of lettuce was 20 mg Cr/kg(-1) soil, and that of the other 4 species was 50 mg Cr/kg(-1) soil. The mitotic index fluctuated with increasing Cr concentration, thus it was insufficient to assess toxicity of Cr in soil. However, micronucleus assay showed that 5 mg Cr/kg(-1) soil caused a significant increase in micronucleus frequency in cabbage, cucumber, and lettuce. For wheat and corn, however, the LOAEC was 20 and 50 mg/Cr/kg(-1) soil, respectively. Furthermore, the analysis of Cr accumulation showed that lettuce significantly accumulated Cr for all the tested concentrations. However, corn and wheat significantly accumulated Cr only with the highest tested dose. This may explain the higher inhibitory effects of Cr on root growth. It can be concluded that root elongation and micronucleus assay are good indicators to assess the phytotoxicity of Cr in soil. Lettuce is the most sensitive species for indicating the toxicity of Cr in soil. PMID:24318542

Hou, Jing-; Liu, Guan-Nan; Xue, Wei; Fu, Wen-Jun; Liang, Bao-Cui; Liu, Xin-Hui

2014-03-01

309

[Seed germination and seedling survival and growth in swamps dominated by palms Raphia tae- digera (Arecaceae) in Tortuguero plains, Costa Rica].  

PubMed

In the marshes dominated by palms, seeds face anaerobic substrates and long flooding periods. Some tree species are capable of growing both in flooded swamps and in areas with lower influence of the flood. I studied the potential settlement of various tree species in different macrohabitats in the Tortuguero floodplain using three experiments: (1) Manicaria saccifera and Raphia taedigera seed germination in palm-swamps and forests of slopes; (2) germination of R. taedigera seeds along a microtopographic gradient; and (3) seed germination and seedling height growth of six woody species (Dipteryx oleifera, Pterocarpus officinalis, Prioria copaifera, Pentaclethra macroloba, Carapa guianensis and Crudia acuminata) and two palms (R. taedigera and Manicaria saccifera) under different forest and swamp habitats. In the first experiment, I found that the palms germinated much earlier in the slope forest than in the palm-swamp. In the second experiment, in drier plots (less effect of flooding) germination began earlier than in the more humid plots. In the third experiment, woody species germinated faster than the studied palms, and some species do not tolerate flooded areas (marshes and swamps), so they cannot germinate or survive in them. Other woody species were removed from the slope forest, probably due to seed predators. Based on the presence or absence of these species in the environment of study were divided into: (1) obliged swamp species (R. taedigera and M saccifera), (2) swamp intolerant (D. oleifera), and (3) facultative wetland species (P officinalis, P copaifera, P macroloba, C. guianensis). Crudia acuminata does not seem to follow any of these categories. PMID:24459752

Myers, Ronald L

2013-09-01

310

[Effects of light and matrix on turion germination, seedling growth and leaf photosynthesis efficiency of Potamogeton crispus].  

PubMed

The study with in-door experiment showed that the germination and seedling rates of Potamogeton crispus were increased under light but without matrix. Matrix promoted root growth, but light could not. The internode's length was obviously longer under dark than under light. After treated with dark, the permeability of leaf plasma membrane raised apparently. Under light condition, the Chla and Chlb contents and Chla/Chlb ratio of seedling' s leaf fluctuated, depending on with or without matrix. The maximum and minimum value of Chla/Chlb ratio was 4. 4 and 2. 8, respectively when the matrix existed, and was 4. 2 and 2. 7 when the matrix was absent. After 40 days of seedling growth, there was a significant difference in the permeability of leaf plasma membrane between the treatments with light and matrix, and with light but without matrix (P < 0.01). A significant difference was also observed in Fv/Fm, and Fv/Fo at the late growth period between the treatments of full (100%) and partial (50%, 20% and 10%) natural light, while no significant difference was found between the treatments of different partial natural light. It was suggested from the measurements of Fv/Fm, Fv/Fo, ETR, qP and qN that weak light promoted the photosynthesis, and slowed down the senile of P. crispus. PMID:17066694

Chen, Xiaofeng; Chen, Kaining; Xiao, Yue'e; Zhang, Shoudong; Wang, Qingya

2006-08-01

311

Circularly Polarized Light and Growth of Plants  

NASA Astrophysics Data System (ADS)

The influence of linearly polarized light on the direction of plants growth has been recently demonstrated. The state of circularly polarized (CP) light can also change when it is reflected from the surface of leaves and stems. However, the role of light handedness in the development of plants and CP light interaction with the complexes of chlorophyll molecules have still not been studied enough. In this work, the role of left CP light in the accelerated growth of lentil and pea plants is revealed and studied. The mechanism of such an enhancement is discussed in terms of the model considering transmission, absorption, and scattering of CP light on micro and macro levels of leaf organization. Theoretical modeling of light interaction with the interior of the leaf was conducted for a number of recently proposed models of organization of chlorophyll molecules and chloroplasts. All the calculations were performed by employing a 4x4 matrix method in solving Maxwell equations. It is shown that left-handed chiral organization of chlorophyll molecules can greatly enhance the absorption of light and therefore lead to the enhanced growth of the whole plant under CP light.

Shibayev, Pavel; Pergolizzi, Robert

2011-03-01

312

Bacterial Ammonia Causes Significant Plant Growth Inhibition  

PubMed Central

Many and complex plant-bacteria inter-relationships are found in the rhizosphere, since plants release a variety of photosynthetic exudates from their roots and rhizobacteria produce multifaceted specialized compounds including rich mixtures of volatiles, e.g., the bouquet of Serratia odorifera 4Rx13 is composed of up to 100 volatile organic and inorganic compounds. Here we show that when growing on peptone-rich nutrient medium S. odorifera 4Rx13 and six other rhizobacteria emit high levels of ammonia, which during co-cultivation in compartmented Petri dishes caused alkalization of the neighboring plant medium and subsequently reduced the growth of A. thaliana. It is argued that in nature high-protein resource degradations (carcasses, whey, manure and compost) are also accompanied by bacterial ammonia emission which alters the pH of the rhizosphere and thereby influences organismal diversity and plant-microbe interactions. Consequently, bacterial ammonia emission may be more relevant for plant colonization and growth development than previously thought. PMID:23691060

Weise, Teresa; Kai, Marco; Piechulla, Birgit

2013-01-01

313

Spectroscopic investigations on plant responses to growth environment.  

E-print Network

??Investigations on plant responses to its growth environment are becoming increasingly important for advanced agriculture. The synergy of plant physiology with optical spectroscopy has enhanced (more)

Li, Bingqing

2010-01-01

314

Effect of Nanoencapsulated Vitamin B1 Derivative on Inhibition of Both Mycelial Growth and Spore Germination of Fusarium oxysporum f. sp. raphani  

PubMed Central

Nanoencapsulation of thiamine dilauryl sulfate (TDS), a vitamin B1 derivative, was proved to effectively inhibit the spore germination of Fusarium oxysporum f. sp. raphani (F. oxysporum), as well as mycelial growth. The average diameter of nanoparticles was measured as 136 nm by being encapsulated with an edible encapsulant, lecithin, whose encapsulation efficiency was about 55% in containing 200 ppm of TDS concentration: the 100 ppm TDS nanoparticle solution showed a mycelial growth inhibition rate of 59%. These results were about similar or even better than the cases of treating 100 ppm of dazomet, a positive antifungal control (64%). Moreover, kinetic analysis of inhibiting spore germination were estimated as 6.6% reduction of spore germination rates after 24 h treatment, which were 3.3% similar to the case of treating 100 ppm of a positive control (dazomet) for the same treatment time. It was also found that TDS itself could work as an antifungal agent by inhibiting both mycelial growth and spore germination, even though its efficacy was lower than those of nanoparticles. Nanoparticles especially played a more efficient role in limiting the spore germination, due to their easy penetration into hard cell membranes and long resident time on the surface of the spore shell walls. In this work, it was first demonstrated that the nanoparticle of TDS not a harmful chemical can control the growth of F. oxysporum by using a lower dosage than commercial herbicides, as well as the inhibiting mechanism of the TDS. However, field trials of the TDS nanoparticles encapsulated with lecithin should be further studied to be effectively used for field applications. PMID:23429270

Cho, Jeong Sub; Seo, Yong Chang; Yim, Tae Bin; Lee, Hyeon Yong

2013-01-01

315

Seed reserve composition in 19 tree species of a tropical deciduous forest in Mexico and its relationship to seed germination and seedling growth  

PubMed Central

Background and Aims The size and composition of seed reserves may reflect the ecological strategy and evolutionary history of a species and also temporal variation in resource availability. The seed mass and composition of seed reserves of 19 co-existing tree species were studied, and we examined how they varied among species in relation to germination and seedling growth rates, as well as between two years with contrasting precipitation (652 and 384 mm). Methods Seeds were collected from a tropical deciduous forest in the northwest of Mexico (Chamela Biological Station). The seed dry mass, with and without the seed coat, and the concentrations of lipids, nitrogen and non-structural carbohydrates for the seed minus seed coat were determined. The anatomical localization of these reserves was examined using histochemical analysis. The germination capacity, rate and lag time were determined. The correlations among these variables, and their relationship to previously reported seedling relative growth rates, were evaluated with and without phylogenetic consideration. Key Results There were interannual differences in seed mass and reserve composition. Seed was significantly heavier after the drier year in five species. Nitrogen concentration was positively correlated with seed coat fraction, and was significantly higher after the drier year in 12 species. The rate and lag time of germination were negatively correlated with each other. These trait correlations were also supported for phylogenetic independent contrasts. Principal component analysis supported these correlations, and indicated a negative association of seedling relative growth rate with seed size, and a positive association of germination rate with nitrogen and lipid concentrations. Conclusions Nitrogen concentration tended to be higher after the drier year and, while interannual variations in seed size and reserve composition were not sufficient to affect interspecific correlations among seed and seedling traits, some of the reserves were related to germination variables and seedling relative growth rate. PMID:21385781

Soriano, Diana; Orozco-Segovia, Alma; Marquez-Guzman, Judith; Kitajima, Kaoru; Gamboa-de Buen, Alicia; Huante, Pilar

2011-01-01

316

Germination and infectivity of microconidia in the rice blast fungus Magnaporthe oryzae  

PubMed Central

The rice blast fungus Magnaporthe oryzae is a model for studying fungalplant interactions. Although it produces two types of spores (microconidia and macroconidia), previous infection studies have exclusively dealt with macroconidia. Germination of microconidia has not been reported, and their role in plant infection is not defined. Here we show that approximately 10% of microconidia germinate on plant surfaces, and that colonies derived from germinated microconidia are normal in growth and pathogenesis. In infection assays with rice and barley seedlings, microconidia fail to infect intact plants, but they can colonize and develop necrotic lesions on wounded leaves and stems. Microconidia also cause disease symptoms on inoculated spikelets in infection assays with barley and Brachypodium heads. Furthermore, microconidia are detected inside rice plants that developed blast lesions under laboratory or field conditions. Therefore, microconidia can germinate and are infectious, and may be an important factor in the rice blast cycle. PMID:25082370

Zhang, Huili; Wu, Zhongshou; Wang, Chenfang; Li, Yang; Xu, Jin-Rong

2014-01-01

317

Bacillus pumilus ES4: candidate plant growth-promoting bacterium to enhance establishment of plants in mine tailings  

PubMed Central

Three plant growth-promoting bacteria (PGPB; Bacillus pumilus ES4, B. pumilus RIZO1, and Azospirillum brasilense Cd) were tested for their ability to enhance plant growth and development of the native Sonoran Desert shrub quailbush (Atriplex lentiformis) and for their effect on the native bacterial community in moderately acidic, high-metal content (AHMT) and in neutral, low metal content natural tailings (NLMT) in controlled greenhouse experiments. Inoculation of quailbush with all three PGPB significantly enhanced plant growth parameters, such as germination, root length, dry weight of shoots and roots, and root/shoot ratio in both types of tailings. The effect of inoculation on the indigenous bacterial community by the most successful PGPB Bacillus pumilus ES4 was evaluated by denaturating gradient gel electrophoresis (PCR-DGGE) fingerprinting and root colonization was followed by specific fluorescent in situ hybridization (FISH). Inoculation with this strain significantly changed the bacterial community over a period of 60 days. FISH analysis showed that the preferred site of colonization was the root tips and root elongation area. This study shows that inoculation of native perennial plants with PGPB can be used for developing technologies for phytostabilizing mine tailings. PMID:25009362

de-Bashan, Luz E.; Hernandez, Juan-Pablo; Bashan, Yoav; Maier, Raina

2014-01-01

318

Gravitational effects on plant growth hormone concentration  

Microsoft Academic Search

Numerous studies, particularly those of H. Dolk in the 1930's, established by means of bio-assay, that more growth hormone diffused from the lower, than from the upper side of a gravity-stimulated plant shoot. Now, using an isotope dilution assay, with 4,5,6,7 tetradeutero indole-3-acetic acid as internal standard, and selected ion monitoring-gas chromatography-mass spectrometry as the method of determination, we have

Robert S. Bandurski; Aga Schulze

1983-01-01

319

Plant Cell Growth in Tissue1[OA  

PubMed Central

Cell walls are part of the apoplasm pathway that transports water, solutes, and nutrients to cells within plant tissue. Pressures within the apoplasm (cell walls and xylem) are often different from atmospheric pressure during expansive growth of plant cells in tissue. The previously established Augmented Growth Equations are modified to evaluate the turgor pressure, water uptake, and expansive growth of plant cells in tissue when pressures within the apoplasm are lower and higher than atmospheric pressure. Analyses indicate that a step-down and step-up in pressure within the apoplasm will cause an exponential decrease and increase in turgor pressure, respectively, and the rates of water uptake and expansive growth each undergo a rapid decrease and increase, respectively, followed by an exponential return to their initial magnitude. Other analyses indicate that pressure within the apoplasm decreases exponentially to a lower value after a step-down in turgor pressure, which simulates its behavior after an increase in expansive growth rate. Also, analyses indicate that the turgor pressure decays exponentially to a constant value that is the sum of the critical turgor pressure and pressure within the apoplasm during stress relaxation experiments in which pressures within the apoplasm are not atmospheric pressure. Additional analyses indicate that when the turgor pressure is constant (clamped), a decrease in pressure within the apoplasm elicits an increase in elastic expansion followed by an increase in irreversible expansion rate. Some analytical results are supported by prior experimental research, and other analytical results can be verified with existing experimental methods. PMID:20739609

Ortega, Joseph K.E.

2010-01-01

320

Low-molecular weight carbohydrates modulate dormancy and are required for post-germination growth in turions of Spirodela polyrhiza.  

PubMed

The aquatic duckweed Spirodela polyrhiza propagates itself vegetatively by forming turions - bud-like perennation organs - in the autumn, which spend the winter on the bottom of ponds and then germinate in the following spring and proliferate on the water surface. Newly formed turions usually require a period of cold after-ripening and light to germinate effectively, but an ample supply of exogenous sugar can lead to germination even in the dark and independent of after-ripening. The results of the present study indicate that the availability of readily metabolised carbohydrates is a determining factor for turion germination. Freshly harvested turions do not contain soluble, low-molecular weight carbohydrates at a level sufficient to allow germination to take place, but after-ripened turions do. Augmentation of the soluble carbohydrate content during after-ripening derives from gradual breakdown of reserve starch of the turions. The long time required for any germination to be observed in turions incubated in darkness and the limited frequency of germination in the dark (about 50% of turion population), even with an ample external sugar, supply emphasise that both after-ripening and light are essential for ensuring rapid germination and subsequent frond proliferation at an ecologically appropriate time. The carbohydrate supply required for rapid proliferation of the fronds produced at germination is provided by the rapid light-induced breakdown of turion reserve starch. PMID:22686442

Appenroth, K-J; Palharini, L; Ziegler, P

2013-03-01

321

Lead stress disrupts the cytoskeleton organization and cell wall construction during Picea wilsonii pollen germination and tube growth.  

PubMed

Lead is a widespread pollutant and has been reported to inhibit pollen tube development, but the mechanism of toxicity involved remains unclear. Here, we report that lead stress significantly prevented Picea wilsonii pollen germination and tube growth and also dramatically altered the tube morphology in a concentration-dependent manner. Fluorescence labeling with JIM 5 (anti-acidic pectin antibody) and Calcofluor white revealed the lead-induced decline of acidic pectin and cellulose, especially in the subapical region. Decolorized aniline blue staining showed the marked accumulation of callose in the apical and subapical regions of lead-treated tubes. Fluorescence labeling with Alexa Fluor 568 phalloidin and anti-tubulin antibody revealed that the distribution of the cytoskeleton in P. wilsonii pollen grains and tubes were developmentally regulated and that lead disturbed the cytoskeleton organization, especially in the shank of the pollen tubes. Taken together, our experiments revealed a link between the dynamics of cytoskeleton organization and the process of P. wilsonii pollen tube development and also indicated that lead disturbed the cytoskeleton assembly and, consequently, cell wall construction. These findings provide new insights into the mechanism of lead toxicity in the tip growth of pollen tubes. PMID:21947795

Sheng, Xianyong; Zhang, Shasha; Jiang, Liping; Li, Kai; Gao, Yuan; Li, Xue

2012-04-01

322

The Growth and Failure of U.S. Manufacturing Plants  

Microsoft Academic Search

This paper examines the patterns of postentry growth and failure for over 200,000 plants that entered the U.S. manufacturing sector in the 1967-77 period. The postentry patterns of growth and failure vary significantly with observable employer characteristics. Plant failure rates decline with size and age as do the growth rates of nonfailing plants. The expected growth rate of a plant,

Timothy Dunne; Mark J. Roberts; Larry Samuelson

1989-01-01

323

Photoperiod regulates elicitation of growth promotion but not induced resistance by plant growth-promoting rhizobacteria  

Microsoft Academic Search

For several years, we have noticed that plant growth-promoting rhizobacteria (PGPR), which consistently promote plant growth in greenhouse tests during spring, summer, and fall, fail to elicit plant growth promotion during the mid- winter under ambient light conditions. This report tests the hypothesis that photoperiod regulates elicitation of growth promotion and induced systemic resistance (ISR) by PGPR. A commercially available

J. W. Kloepper; A. Gutirrez-Estrada; J. A. McInroy

2007-01-01

324

Protein mobilization in germinating mung bean seeds involves vacuolar sorting receptors and multivesicular bodies.  

PubMed

Plants accumulate and store proteins in protein storage vacuoles (PSVs) during seed development and maturation. Upon seed germination, these storage proteins are mobilized to provide nutrients for seedling growth. However, little is known about the molecular mechanisms of protein degradation during seed germination. Here we test the hypothesis that vacuolar sorting receptor (VSR) proteins play a role in mediating protein degradation in germinating seeds. We demonstrate that both VSR proteins and hydrolytic enzymes are synthesized de novo during mung bean (Vigna radiata) seed germination. Immunogold electron microscopy with VSR antibodies demonstrate that VSRs mainly locate to the peripheral membrane of multivesicular bodies (MVBs), presumably as recycling receptors in day 1 germinating seeds, but become internalized to the MVB lumen, presumably for degradation at day 3 germination. Chemical cross-linking and immunoprecipitation with VSR antibodies have identified the cysteine protease aleurain as a specific VSR-interacting protein in germinating seeds. Further confocal immunofluorescence and immunogold electron microscopy studies demonstrate that VSR and aleurain colocalize to MVBs as well as PSVs in germinating seeds. Thus, MVBs in germinating seeds exercise dual functions: as a storage compartment for proteases that are physically separated from PSVs in the mature seed and as an intermediate compartment for VSR-mediated delivery of proteases from the Golgi apparatus to the PSV for protein degradation during seed germination. PMID:17322331

Wang, Junqi; Li, Yubing; Lo, Sze Wan; Hillmer, Stefan; Sun, Samuel S M; Robinson, David G; Jiang, Liwen

2007-04-01

325

Assessment of Parameter Uncertainty in Plant Growth Model Identification  

E-print Network

Assessment of Parameter Uncertainty in Plant Growth Model Identification Yuting CHEN, Paul: yuting.chen@ecp.fr Abstract--For the parametric identification of plant growth models, we generally face; Parameter estima- tion; Particle filtering; Plant growth model; LNAS. I. Introduction Accurate

Boyer, Edmond

326

Plant Growth Measurement Techniques Using Near-Infrared  

E-print Network

Plant Growth Measurement Techniques Using Near-Infrared Imagery Amr Aboelela John Barron Dept, for measuring plant growth for corn seedlings and Caster Oil Bean leaves. A near-infrared camera, which allows are interested in the measurement of plant growth using optical ow. We use a near infrared-camera with near

Barron, John

327

Transformation of the Plant Growth Regulator Daminozide (Alar) and  

E-print Network

Transformation of the Plant Growth Regulator Daminozide (Alar) and Structurally Related Compounds,N- Dimethylsuccinamic acid (SA), in contrast, breaks down via a hydrolytic mechanism. Introduction The plant growth heavily used plant growth regulators in the U.S. (5). In addition to daminozide, the hydrazide moiety

Huang, Ching-Hua

328

Selecting and Using Plant Growth Regulators on Floricultural Crops  

E-print Network

#12;Selecting and Using Plant Growth Regulators on Floricultural Crops Joyce Latimer, Extension Carolina State University #12;Selecting and Using Plant Growth Regulators on Floricultural Crops Optimizing of controlling plant growth is to withhold water. Drought stress can be used on a num- ber of crops, including

Liskiewicz, Maciej

329

Plant Growth Response in a Simulated Electric Field-environment  

Microsoft Academic Search

THE physiological effects on plant growth and plant growth response of environmental factors such as moisture, light, temperature, and similar functions are well documented. Literature relating almost all aspects of these environmental conditions is also quite extensive. Yet little is known of the physiological influence on plant growth of the electric field environment which prevails at all times everywhere. This

L. E. Murr

1963-01-01

330

Enhanced germination and gravitropism of soybean in a hypogeomagnetic field  

Microsoft Academic Search

For the future manned space exploration, the duration of the missions would significantly in-crease. Investigating plant growth and development under the space environmental conditions is of essential importance for the food supply projects for the astronauts. Hypogeomagnetic field (HGMF), namely, extremely low magnetic field, is one of the main characters of the space environment. Germination is the first vital step

Weichuan Mo

2010-01-01

331

Fungal specificity bottlenecks during orchid germination and development  

Microsoft Academic Search

Fungus-subsidized growth through the seedling stage is the most critical feature of the life history for the thousands of mycorrhizal plant species that propagate by means of 'dust seeds.' We investigated the extent of specificity towards fungi shown by orchids in the genera Cephalanthera and Epipactis at three stages of their life cycle: (i) initiation of germination, (ii) during seedling

MARTIN I. BIDARTONDO; DAVID J. READ

2008-01-01

332

Growth and mitochondrial respiration of mungbeans (Phaseolus aureus Roxb.) germinated at low pressure  

NASA Technical Reports Server (NTRS)

Mungbean (Phaseolus aureus Roxb.) seedlings were grown hypobarically to assess the effects of low pressure (21-24 kilopascals) on growth and mitochondrial respiration. Control seedlings grown at ambient pressure (101 kilopascals) were provided amounts of O2 equivalent to those provided experimental seedlings at reduced pressure to factor out responses to O2 concentration and to total pressure. Respiration was assayed using washed mitochondria, and was found to respond only to O2 concentration. Regardless of total pressure, seedlings grown at 2 millimoles O2 per liter had higher state 3 respiration rates and decreased percentages of alternative respiration compared to ambient (8.4 millimoles O2 per liter) controls. In contrast, seedling growth responded to total pressure but not to O2 concentration. Seedlings were significantly larger when grown under low pressure. While low O2 (2 millimoles O2 per liter) diminished growth at ambient pressure, growth at low pressure in the same oxygen concentration was enhanced. Respiratory development and growth of mungbean seedlings under low pressure is unimpaired whether oxygen or air is used as the chamber gas, and further, low pressure can improve growth under conditions of poor aeration.

Musgrave, M. E.; Gerth, W. A.; Scheld, H. W.; Strain, B. R.

1988-01-01

333

Effects of Oilseed Meals on the Germination, Growth, and Survival of Crop and Weed Species  

E-print Network

. (2008) planted 20 seeds of common chickweed (Stellaria media ) and annual bluegrass (Poa annua ) in containers with transplanted ornamentals. White mustard SM was then surface applied at rates of 0, 113, 225, and 450 g m-2. Seed meal inhibited.... (2008) planted 20 seeds of common chickweed (Stellaria media ) and annual bluegrass (Poa annua ) in containers with transplanted ornamentals. White mustard SM was then surface applied at rates of 0, 113, 225, and 450 g m-2. Seed meal inhibited...

Rothlisberger, Katie Lynn

2012-02-14

334

Dynamic Adaption of Metabolic Pathways during Germination and Growth of Lily Pollen Tubes after Inhibition of the Electron Transport Chain1[W][OPEN  

PubMed Central

Investigation of the metabolome and the transcriptome of pollen of lily (Lilium longiflorum) gave a comprehensive overview of metabolic pathways active during pollen germination and tube growth. More than 100 different metabolites were determined simultaneously by gas chromatography coupled to mass spectrometry, and expressed genes of selected metabolic pathways were identified by next-generation sequencing of lily pollen transcripts. The time-dependent changes in metabolite abundances, as well as the changes after inhibition of the mitochondrial electron transport chain, revealed a fast and dynamic adaption of the metabolic pathways in the range of minutes. The metabolic state prior to pollen germination differed clearly from the metabolic state during pollen tube growth, as indicated by principal component analysis of all detected metabolites and by detailed observation of individual metabolites. For instance, the amount of sucrose increased during the first 60 minutes of pollen culture but decreased during tube growth, while glucose and fructose showed the opposite behavior. Glycolysis, tricarbonic acid cycle, glyoxylate cycle, starch, and fatty acid degradation were activated, providing energy during pollen germination and tube growth. Inhibition of the mitochondrial electron transport chain by antimycin A resulted in an immediate production of ethanol and a fast rearrangement of metabolic pathways, which correlated with changes in the amounts of the majority of identified metabolites, e.g. a rapid increase in ?-aminobutyric acid indicated the activation of a ?-aminobutyric acid shunt in the tricarbonic acid cycle, while ethanol fermentation compensated the reduced ATP production after inhibition of the oxidative phosphorylation. PMID:23660836

Obermeyer, Gerhard; Fragner, Lena; Lang, Veronika; Weckwerth, Wolfram

2013-01-01

335

Siderophore as a potential plant growth-promoting agent produced by Pseudomonas aeruginosa JAS-25.  

PubMed

Siderophores scavenges Fe(+3) from the vicinity of the roots of plants, and thus limit the amount of iron required for the growth of pathogens such as Fusarium oxysporum, Pythium ultimum, and Fusarium udum, which cause wilt and root rot disease in crops. The ability of Pseudomonas to grow and to produce siderophore depends upon the iron content, pH, and temperature. Maximum yield of siderophore of 130 ?M was observed at pH 7.0 0.2 and temperature of 30 C at 30 h. The threshold level of iron was 50 ?M, which increases up to 150 ?M, favoring growth but drastically affecting the production of siderophore by Pseudomonas aeruginosa JAS-25. The seeds of agricultural crops like Cicer arietinum (chick pea), Cajanus cajan (pigeon pea), and Arachis hypogaea (ground nut) were treated with P. aeruginosa JAS-25, which enhanced the seed germination, root length, shoot length, and dry weight of chick pea, pigeon pea, and ground nut plants under pot studies. The efficient growth of the plants was not only due to the biocontrol activity of the siderophore produced by P. aeruginosa JAS-25 but also may be by the production of indole acetic acid (IAA), which influences the growth of the plants as phytohormones. PMID:25062779

Sulochana, M B; Jayachandra, S Y; Kumar, S Anil; Parameshwar, A B; Reddy, K Mohan; Dayanand, A

2014-09-01

336

Mechanisms of Glucose Signaling during Germination of Arabidopsis1  

PubMed Central

Glucose (Glc) signaling, along with abscisic acid (ABA) signaling, has been implicated in regulating early plant development in Arabidopsis. It is generally believed that high levels of exogenous Glc cause ABA accumulation, which results in a delay of germination and an inhibition of seedling developmenta typical stress response. To test this hypothesis and decipher the complex interactions that occur in the signaling pathways, we determined the effects of sugar and ABA on one developmental event, germination. We show that levels of exogenous Glc lower than previously cited could delay the rate of seed germination in wild-ecotype seeds. Remarkably, this effect could not be mimicked by an osmotic effect, and ABA was still involved. With higher concentrations of Glc, previously known Glc-insensitive mutants gin2 and abi4 exhibited germination kinetics similar to wild type, indicating that Glc-insensitive phenotypes are not the same for all developmental stages of growth and that the signaling properties of Glc vary with concentration. Higher concentrations of Glc were more potent in delaying seed germination. However, Glc-delayed seed germination was not caused by increased cellular ABA concentration, rather Glc appeared to slow down the decline of endogenous ABA. Except for the ABA-insensitive mutants, all tested genotypes appeared to have similar ABA perception during germination, where germination was correlated with the timing of ABA drop to a threshold level. In addition, Glc was found to modulate the transcription of genes involved in ABA biosynthesis and perception only after germination, suggesting a critical role of the developmental program in sugar sensing. On the basis of an extensive phenotypic, biochemical, and molecular analysis, we suggest that exogenous Glc application creates specific signals that vary with concentration and the developmental stage of the plant and that Glc-induced fluctuations in endogenous ABA level generate a different set of signals than those generated by external ABA application. PMID:12857824

Price, John; Li, Tsai-Chi; Kang, Shin Gene; Na, Jong Kuk; Jang, Jyan-Chyun

2003-01-01

337

Mechanisms of glucose signaling during germination of Arabidopsis.  

PubMed

Glucose (Glc) signaling, along with abscisic acid (ABA) signaling, has been implicated in regulating early plant development in Arabidopsis. It is generally believed that high levels of exogenous Glc cause ABA accumulation, which results in a delay of germination and an inhibition of seedling development-a typical stress response. To test this hypothesis and decipher the complex interactions that occur in the signaling pathways, we determined the effects of sugar and ABA on one developmental event, germination. We show that levels of exogenous Glc lower than previously cited could delay the rate of seed germination in wild-ecotype seeds. Remarkably, this effect could not be mimicked by an osmotic effect, and ABA was still involved. With higher concentrations of Glc, previously known Glc-insensitive mutants gin2 and abi4 exhibited germination kinetics similar to wild type, indicating that Glc-insensitive phenotypes are not the same for all developmental stages of growth and that the signaling properties of Glc vary with concentration. Higher concentrations of Glc were more potent in delaying seed germination. However, Glc-delayed seed germination was not caused by increased cellular ABA concentration, rather Glc appeared to slow down the decline of endogenous ABA. Except for the ABA-insensitive mutants, all tested genotypes appeared to have similar ABA perception during germination, where germination was correlated with the timing of ABA drop to a threshold level. In addition, Glc was found to modulate the transcription of genes involved in ABA biosynthesis and perception only after germination, suggesting a critical role of the developmental program in sugar sensing. On the basis of an extensive phenotypic, biochemical, and molecular analysis, we suggest that exogenous Glc application creates specific signals that vary with concentration and the developmental stage of the plant and that Glc-induced fluctuations in endogenous ABA level generate a different set of signals than those generated by external ABA application. PMID:12857824

Price, John; Li, Tsai-Chi; Kang, Shin Gene; Na, Jong Kuk; Jang, Jyan-Chyun

2003-07-01

338

Germination Response of MR 219 Rice Variety to Different Exposure Times and Periods of 2450 MHz Microwave Frequency  

PubMed Central

Germination is a key process in plants' phenological cycles. Accelerating this process could lead to improvment of the seedling growth as well as the cultivation efficiency. To achieve this, the effect of microwave frequency on the germination of rice seeds was examined. The physiological feedbacks of the MR 219 rice variety in terms of seed germination rate (GR), germination percentage (GP), and mean germination time (MGT) were analyzed by exposing its seeds to 2450?MHz of microwave frequency for one, four, seven, and ten hours. It was revealed that exposing the seeds to the microwave frequency for 10 hours resulted in the highest GP. This treatment led to 100% of germination after three days with a mean germination time of 2.1 days. Although the other exposure times of microwave frequency caused the moderate effects on germination with a GPa3 ranged from 93% to 98%, they failed to reduce the MGTa3. The results showed that ten-hour exposure times of microwave frequency for six days significantly facilitated and improved the germination indices (primary shoot and root length). Therefore, the technique is expected to benefit the improvement of rice seed germination considering its simplicity and efficacy in increasing the germination percentage and rate as well as the primary shoot and root length without causing any environmental toxicity. PMID:24307869

Valdiani, Alireza; Maziah, Mahmood; Mohsenkhah, Mohammad

2013-01-01

339

Germination response of MR 219 rice variety to different exposure times and periods of 2450 MHz microwave frequency.  

PubMed

Germination is a key process in plants' phenological cycles. Accelerating this process could lead to improvment of the seedling growth as well as the cultivation efficiency. To achieve this, the effect of microwave frequency on the germination of rice seeds was examined. The physiological feedbacks of the MR 219 rice variety in terms of seed germination rate (GR), germination percentage (GP), and mean germination time (MGT) were analyzed by exposing its seeds to 2450 MHz of microwave frequency for one, four, seven, and ten hours. It was revealed that exposing the seeds to the microwave frequency for 10 hours resulted in the highest GP. This treatment led to 100% of germination after three days with a mean germination time of 2.1 days. Although the other exposure times of microwave frequency caused the moderate effects on germination with a GP(a3) ranged from 93% to 98%, they failed to reduce the MGT(a3). The results showed that ten-hour exposure times of microwave frequency for six days significantly facilitated and improved the germination indices (primary shoot and root length). Therefore, the technique is expected to benefit the improvement of rice seed germination considering its simplicity and efficacy in increasing the germination percentage and rate as well as the primary shoot and root length without causing any environmental toxicity. PMID:24307869

Talei, Daryush; Valdiani, Alireza; Maziah, Mahmood; Mohsenkhah, Mohammad

2013-01-01

340

Changes in Esters of Fatty Acids of Rhizopus arrhizus During Germination and Growth  

PubMed Central

Natural esters of fatty acids of Rhizopus arrhizus Fischer increased during the first 48 hr of growth. During the 48- to 72-hr period, there was a shift in concentration from the methyl esters to the ethyl esters of fatty acids. PMID:5079078

Hess, S. L.; Weber, D. J.; Gunasekaran, M.

1972-01-01

341

EFFECTS OF OZONE ON SPORULATION, SPORE GERMINATION, AND GROWTH OF FOMES ANNOSUS  

EPA Science Inventory

Effects of ozone (O3) on certain cultural characteristics of Fomes annosus were investigated in exposure chamber studies. Growth rates of F. annosus decreased and conidial germ tubes were shorter and had fewer branches as O3 dosages increased. F. annosus conidial production was v...

342

Effects of aliphatic acids on seed germination and seedling growth in soil  

Microsoft Academic Search

It is commonly assumed that the adverse effect of plant residues on crop yields is largely, or partly, due to phytotoxic compounds leached from these residues or produced by their decomposition, and it has been suggested that the phytotoxic compounds responsible for reduced crop yields are aliphatic acids such as acetic acid, butyric acid, and propionic acid. To test the

M. J. Krogmeier; J. M. Bremner

1990-01-01

343

Gravitational effects on plant growth hormone concentration  

NASA Technical Reports Server (NTRS)

Dolk's (1936) finding that more growth hormone diffuses from the lower side of a gravity-stimulated plant shoot than from the upper side is presently confirmed by means of both an isotope dilution assay and selected ion monitoring-gas chromatography-mass spectrometry, and it is established that the asymmetrically distributed hormone is indole-3-acetic acid (IAA). This is the first physicochemical demonstration that there is more IAA on the lower sides of a geostimulated plant shoot. It is also found that free IAA primarily occurs in the conductive vascular tissues of the shoot, while IAA esters predominate in the growing cortical cells. A highly sensitive gas chromatographic isotope dilution assay shows that the hormone asymmetry also occurs in the nonvascular tissue.

Bandurski, R. S.; Schulze, A.

1983-01-01

344

Interaction between seed size and NaCl on germination and early seedling growth of some Turkish cultivars of chickpea ( Cicer arietinum L.)  

Microsoft Academic Search

Chickpea is an important food legume crop of Turkey and is largely grown for human consumption on low moisture or salt-affected\\u000a soils. The objective of the study was to find the effects of NaCl stress at electrical conductivities of 4.5, 8.6, 12.7 and\\u000a 16.3 dS\\/m and seed sizes (7, 8 and 9 mm) on germination and early seedling growth of

Muharrem Kaya; Gamze Kaya; Mehmet Demir Kaya; Mehmet Atak; Sevil Saglam; Khalid Mahmood Khawar; Cemalettin Yasar Ciftci

2008-01-01

345

Effects of seven pure flavonoids from mosses on germination and growth of Tortula muralis HEDW. (Bryophyta) and Raphanus sativus L. (Magnoliophyta)  

Microsoft Academic Search

Dried mosses (five moss species) were progressively extracted and subjected to a four-step Craig distribution. Seven pure flavonoids were isolated and identified. The flavonoids were the flavones apigenin, apigenin-7-O-triglycoside, lucenin-2, luteolin-7-O-neohesperidoside, saponarine and vitexin; and the biflavonoid bartramiaflavone and they were submitted to biological tests. The tests were performed in vitro on spore germination and protonemal growth of the moss

Adriana Basile; Sergio Sorbo; Jos Antonio Lpez-Sez; Rosa Castaldo Cobianchi

2003-01-01

346

Seed production, germinability and seedling growth for a bird-pollinated shrub in fragments of kwongan in south-west Australia  

Microsoft Academic Search

In this study we investigate the effect of population size on the proportion of flowers that produce a fruit (fruit set), the number of seeds per fruit (seed set), seed germinability, seedling mortality and growth in a range of population fragments for the bird-pollinated mixed mating system shrub Calothamnus quadrifidus R. Br. (Myrtaceae). We found no significant linear relationship (p<0.05)

Colin J. Yates; Carole Elliott; Margaret Byrne; David J. Coates; Richard Fairman

2007-01-01

347

Antrodia camphorata Grown on Germinated Brown Rice Suppresses Melanoma Cell Proliferation by Inducing Apoptosis and Cell Differentiation and Tumor Growth  

PubMed Central

Antrodia camphorata grown on germinated brown rice (CBR) was prepared to suppress melanoma development. CBR extracts were divided into hexane, EtOAc, BuOH, and water fractions. Among all the fractions, EtOAc fraction showed the best suppressive effect on B16F10 melanoma cell proliferation by CCK-8 assay. It also showed the increased cell death and the changed cellular morphology after CBR treatment. Annexin V-FITC/PI, flow cytometry, and western blotting were performed to elucidate anticancer activity of CBR. The results showed that CBR induced p53-mediated apoptotic cell death of B16F10. CBR EtOAc treatment increased melanin content and melanogenesis-related proteins of MITF and TRP-1 expressions, which supports its anticancer activity. Its potential as an anticancer agent was further investigated in tumor-xenografted mouse model. In melanoma-xenografted mouse model, melanoma tumor growth was significantly suppressed under CBR EtOAc fraction treatment. HPLC analysis of CBR extract showed peak of adenosine. In conclusion, CBR extracts notably inhibited B16F10 melanoma cell proliferation through the p53-mediated apoptosis induction and increased melanogenesis. These findings suggest that CBR EtOAc fraction can act as an effective anticancer agent to treat melanoma. PMID:23533475

Song, Minjung; Park, Dong Ki; Park, Hye-Jin

2013-01-01

348

Improvement of plant growth and nickel uptake by nickel resistant-plant-growth promoting bacteria  

Microsoft Academic Search

In this study, among a collection of Ni-resistant bacterial strains isolated from the rhizosphere of Alyssum serpyllifolium and Phleum phleoides grown on serpentine soil, five plant growth-promoting bacteria (PGPB) were selected based on their ability to utilize 1-aminocyclopropane-1-carboxylate (ACC) as the sole N source and promote seedling growth. All of the strains tested positive for indole-3-acetic acid (IAA) production and

Ying Ma; Mani Rajkumar; Helena Freitas

2009-01-01

349

PROMOTION OF PLANT GROWTH BY SOIL BACTERIA THAT REGULATE PLANT ETHYLENE LEVELS  

Microsoft Academic Search

One of the central the mechanisms used by many soil bacteria to directly promote plant growth is the production of the enzyme 1-aminocyclopropane-1-carboxylate (ACC) deaminase. This enzyme facilitates plant growth as a consequence of the fact that it sequesters and cleaves plant- produced ACC (the immediate precursor of ethylene in plants), thereby lowering the level of ethylene in the plant.

Bernard R. Glick

350

PLANT-ANIMAL INTERACTIONS -ORIGINAL RESEARCH Plant defense, herbivory, and the growth of Cordia alliodora trees  

E-print Network

defense, tolerance, and herbivore pressure. In symbiotic ant­plant mutualisms, plants provide nesting in defense are idiosyn- cratic, depending on plant growth form, herbivore guild, and defensive trait strategyPLANT-ANIMAL INTERACTIONS - ORIGINAL RESEARCH Plant defense, herbivory, and the growth of Cordia

Gordon, Deborah

351

Effects of biogas digestate on soil properties and plant growth  

NASA Astrophysics Data System (ADS)

Farming methods and food industries generate large amounts manure and other useful raw materials that need safe disposal. Following the international trends great numbers of biogas plants were opened during the last few years in Hungary. However this issue presents a number of new questions, including the subsequent use of anaerobic fermentation residues. So far we have only limited information about it's agricultural applications. Farmers and authorities are very skeptic because feedstocks are very different so the endproduct will be different, too. However, this endproduct can be applied as fertilizer. The aim of our work is to determine the effects of this product in plant-soil system. Digestate contains high amount of nitrogen which is present mainly ammonium form and this form can cause root depression and lower germination rates. Pot experiments were established with different rates of nitrogen content (80 kg ha-1N, 120 kg ha-1N, 170 kg ha-1N, and control). Maximum rates were determine by the Nitrate Directive. Soil moisture was 60% of maximum of water capacity. Digestate and distilled water were homogenized and added to 200g loamy soil. Rye-grass (Lolium perenne) was applied as a test plant. Treatments were randomized design and 10 replications. Three pot from each treatment were used to observe the germination and progress of plants. We investigated the effect of the digestate on nitrate- and ammonium-ion content of soil. The amount of nitrate- and ammonium-N of soil was determine with distillation. The ammonium-N levels increased with the doses on the first day but on the sixth-seventh day this amount totally falled down, because NH4-N transformed to NO3-N. Nitrate level increased continuously untill the tenth day, later decreased as the result of the plant and microbes consumption. The increasing doses inhibited the germination and root development of the plants. We experienced fewer roots, which were different form control.

Gulys, Mikls; Fleky, Gyrgy

2013-04-01

352

The class IId bacteriocin thuricin17 increases plant growth  

Microsoft Academic Search

The mechanisms by which many plant growth promoting rhizobacteria (PGPR) affect plants are unknown. We recently isolated a\\u000a rhizosphere bacterium (Bacillus thuringiensis NEB17), that promotes soybean growth and screened the liquid growth medium in which it grew for plant growth stimulating\\u000a materials. We have also shown that it produces a bacteriocin (named by us as thuricin-17 and a member of

Kyung Dong Lee; Elizabeth J. Gray; Fazli Mabood; Woo-Jin Jung; Trevor Charles; Scott R. D. Clark; Anh Ly; Alfred Souleimanov; Xiaomin Zhou; Donald Lawrence Smith

2009-01-01

353

Mechanisms Used by Plant Growth-Promoting Bacteria  

Microsoft Academic Search

\\u000a Plant growth-promoting bacteria (PGPB) facilitate plant growth in two ways, either by direct stimulation or by biocontrol\\u000a (i.e., suppressive activity against soil-borne diseases). The direct stimulation of plant growth may be a consequence of nitrogen\\u000a fixation, phosphate solubilization, iron sequestration, synthesis of phytohormones (such as auxins, cytokinins, and gibberellins),\\u000a or modulation of plant ethylene levels. The biocontrol activity of PGPB

Elisa Gamalero; Bernard R. Glick

354

Allelopathic effects of juglone on germination and growth of several herbaceous and woody species  

Microsoft Academic Search

Laboratory experiments were conducted to determine juglone sensitivity of 16 species (Trifolium incarnatum, Coronilla varia, Vicia villosa, Lespedeza stipulacea, L. cuneata, Acer ginnala, Caragana arbor-escens, Elaegnus angustifolia, E. umbellata, Lonicera maackii, Quercus alba, Fraxinus americana, Liriodendron tulipifera, Alnus glutinosa, Pinus strobus, andP. sylvestris) being considered for mixed plantings withJugions nigra (black walnut). All species were sensitive to juglone, but seed

W. J. Rietveld

1983-01-01

355

Oxidative signaling in seed germination and dormancy  

PubMed Central

Reactive Oxygen Species (ROS) play a key role in various events of seed life. In orthodox seeds, ROS are produced from embryogenesis to germination, i.e., in metabolically active cells, but also in quiescent dry tissues during after ripening and storage, owing various mechanisms depending on the seed moisture content. Although ROS have been up to now widely considered as detrimental to seeds, recent advances in plant physiology signaling pathways has lead to reconsider their role. ROS accumulation can therefore be also beneficial for seed germination and seedling growth by regulating cellular growth, ensuring a protection against pathogens or controlling the cell redox status. ROS probably also act as a positive signal in seed dormancy release. They interact with abscisic acid and gibberellins transduction pathway and are likely to control numerous transcription factors and properties of specific protein through their carbonylation. PMID:19513212

El-Maarouf-Bouteau, Hayat

2008-01-01

356

Abscisic acid metabolizing rhizobacteria decrease ABA concentrations in planta and alter plant growth.  

PubMed

Although endogenous phytohormones such as abscisic acid (ABA) regulate root growth, and many rhizobacteria can modulate root phytohormone status, hitherto there have been no reports of rhizobacteria mediating root ABA concentrations and growth by metabolising ABA. Using a selective ABA-supplemented medium, two bacterial strains were isolated from the rhizosphere of rice (Oryza sativa) seedlings grown in sod-podzolic soil and assigned to Rhodococcus sp. P1Y and Novosphingobium sp. P6W using partial 16S rRNA gene sequencing and phenotypic patterns by the GEN III MicroPlate test. Although strain P6W had more rapid growth in ABA-supplemented media than strain P1Y, both could utilize ABA as a sole carbon source in batch culture. When rice seeds were germinated on filter paper in association with bacteria, root ABA concentration was not affected, but shoot ABA concentration of inoculated plants decreased by 14% (strain P6W) and 22% (strain P1Y). When tomato (Solanum lycopersicum) genotypes differing in ABA biosynthesis (ABA deficient mutants flacca - flc, and notabilis - not and the wild-type cv. Ailsa Craig, WT) were grown in gnotobiotic cultures on nutrient solution agar, rhizobacterial inoculation decreased root and/or leaf ABA concentrations, depending on plant and bacteria genotypes. Strain P6W inhibited primary root elongation of all genotypes, but increased leaf biomass of WT plants. In WT plants treated with silver ions that inhibit ethylene perception, both ABA-metabolising strains significantly decreased root ABA concentration, and strain P6W decreased leaf ABA concentration. Since these changes in ABA status also occurred in plants that were not treated with silver, it suggests that ethylene was probably not involved in regulating bacteria-mediated changes in ABA concentration. Correlations between plant growth and ABA concentrations in planta suggest that ABA-metabolising rhizobacteria may stimulate growth via an ABA-dependent mechanism. PMID:24270514

Belimov, Andrey A; Dodd, Ian C; Safronova, Vera I; Dumova, Valentina A; Shaposhnikov, Alexander I; Ladatko, Alexander G; Davies, William J

2014-01-01

357

Differentially expressed myo-inositol monophosphatase gene (CaIMP) in chickpea (Cicer arietinum L.) encodes a lithium-sensitive phosphatase enzyme with broad substrate specificity and improves seed germination and seedling growth under abiotic stresses  

PubMed Central

myo-Inositol monophosphatase (IMP) is an essential enzyme in the myo-inositol metabolic pathway where it primarily dephosphorylates myo-inositol 1-phosphate to maintain the cellular inositol pool which is important for many metabolic and signalling pathways in plants. The stress-induced increased accumulation of inositol has been reported in a few plants including chickpea; however, the role and regulation of IMP is not well defined in response to stress. In this work, it has been shown that IMP activity is distributed in all organs in chickpea and was noticeably enhanced during environmental stresses. Subsequently, using degenerate oligonucleotides and RACE strategy, a full-length IMP cDNA (CaIMP) was cloned and sequenced. Biochemical study revealed that CaIMP encodes a lithium-sensitive phosphatase enzyme with broad substrate specificity, although maximum activity was observed with the myo-inositol 1-phosphate and l-galactose 1-phosphate substrates. Transcript analysis revealed that CaIMP is differentially expressed and regulated in different organs, stresses and phytohormones. Complementation analysis in Arabidopsis further confirmed the role of CaIMP in l-galactose 1-phosphate and myo-inositol 1-phosphate hydrolysis and its participation in myo-inositol and ascorbate biosynthesis. Moreover, Arabidopsis transgenic plants over-expressing CaIMP exhibited improved tolerance to stress during seed germination and seedling growth, while the VTC4/IMP loss-of-function mutants exhibited sensitivity to stress. Collectively, CaIMP links various metabolic pathways and plays an important role in improving seed germination and seedling growth, particularly under stressful environments. PMID:24123252

Majee, Manoj

2013-01-01

358

A growth inhibitory factor from lambsquarters ( Chenopodium album )  

Microsoft Academic Search

Aqueous extract of air-dried lambsquarters (Chenopodium album) at 25 mg\\/ml significantly inhibited germination and growth of radish and wheat seeds. Soybean seed germination was not inhibited; however, hypocotyl growth was significantly reduced. Germination of radish seeds in sand amended with pulverized lambsquarters shoots at 2 and 4 mg\\/g was reduced 40 and 95%, respectively. Shoot dry weight and plant height

M. A. B. Mallik; R. Puchala; F. A. Grosz

1994-01-01

359

The role of phytochelates in plant growth and productivity  

Microsoft Academic Search

Plants require minimal amounts of certain metals (Zn,Fe,Cu,etc) for optimal growth and productivity, but excess of these metals leads to cell death. When growth is limited by metal excess or metal deficiency plants respond by synthesizing nonproteinogenic chelating substances. Phytosiderophores are secreted by roots of iron deficient grasses and are important in providing sufficient Fe for normal growth. In response

A. M. Kinnersley

1993-01-01

360

Cooperation among germinating spores facilitates the growth of the fungus, Neurospora crassa  

PubMed Central

Fusions between individuals are a common feature of organisms with modular, indeterminate life forms, including plants, marine invertebrates and fungi. The consequences of fusion for an individual fungus are poorly understood. We used wild-type and fusion mutant strains of the genetic model Neurospora crassa to chronicle the fitness in two different laboratory habitats, and in each experiment started colonies from multiple different densities of asexual spores. On round Petri dishes, fusion enabled wild-type colonies to grow larger than mutant (soft) colonies; but in linear race tubes, the soft mutant always grew more quickly than the wild-type. Starting a colony with more spores always provided an advantage to a wild-type colony, but was more often neutral or a cost to the soft mutant. The ability to fuse does not provide a consistent advantage to wild-type colonies; net benefits are shaped by both habitat and initial spore densities. PMID:22258449

Richard, F.; Glass, N. L.; Pringle, A.

2012-01-01

361

Plant Growth Under Light Emitting Diode Irradiation.  

NASA Astrophysics Data System (ADS)

Plant growth under light emitting diodes (LEDs) was investigated to determine if LEDs would be useful to provide radiant energy for two plant processes, photosynthesis and photomorphogenesis. Photosynthesis of tomato (Lycopersicon esculentum L.) and Kudzu (Pueraria lobata (Willd) Ohwi.) was measured using photons from LEDs to answer the following: (1) Are leaves able to use red LED light for photosynthesis? and (2) Is the efficiency of photosynthesis in pulsed light equal to that of continuous light? In 175 Pa CO _2, or in response to changes in CO _2,<=af photosynthesis and ATP status were the same in LED as in white xenon arc light. In 35 Pa CO_2, photosynthesis was 10% lower in LED than in xenon arc light due to lowered stomatal conductance. The quantum efficiency of photosynthesis in pulsed light was equal to continuous light, even when pulses were twice as bright as sunlight. Xanthophyll pigments were not affected by these bright pulses. Photomorphogenesis of tobacco (Nicotiana tabacum L.), tomato (Lycopersicon esculentum Mill.) and transformed tobacco and tomato (expressing oat phytochrome-A) was assessed by growing plants under red LED lamps in an attempt to answer the following: (1) What is the developmental response of non-transformed and transformed tobacco to red LED light? and (2) Can tomato plants that grow tall and spindly in red LED light be made to grow short by increasing the amount of phytochrome-A? The short phenotype of transformed tobacco was not evident when plants were grown in LED light. Addition of photons of far-red or blue light to red light resulted in short transformed tobacco. Tomato plants grew three times as tall and lacked leaf development in LED versus white light, but transformed tomato remained short and produced fruit under LED light. I have determined that the LED photons are useful for photosynthesis and that the photon efficiency of photosynthesis is the same in pulsed as in continuous light. From responses of tobacco, I concluded that the P_{ rm r} form of phytochrome-A and the phytochrome cycling rate mediate responses. In tomato, increased amounts of Phytochrome-A prevented stem elongation and caused chlorophyll accumulation in LED light.

Tennessen, Daniel John

362

Plant Physiology: Manipulating Plant Growth with Solar Radiation Dennis Decoteau, Ph.D.  

E-print Network

for the plant is used for producing food through the process of photosynthesis. The characteristics of direction (Villee, 1977). Plant Uses Of Radiant Energy And Plant "Vision" Plants utilize specialized pigmentsPlant Physiology: Manipulating Plant Growth with Solar Radiation Dennis Decoteau, Ph.D. Department

Decoteau, Dennis R.

363

Phytotoxical effect of Lepidium draba L. extracts on the germination and growth of monocot (Zea mays L.) and dicot (Amaranthus retroflexus L.) seeds.  

PubMed

Laboratory experiments were performed to determine phytotoxic potentials of white top (Lepidium draba) methanol extracts (root, stem and leaf) on germination and early growth of corn (Zea mays) and redroot pigweed (Amaranthus retroflexus). Furthermore, the effects of different methanol extracts of L. draba on the phytohormone (indole-3-acetic acid (IAA), gibberellic acid (GA), abscisic acid (ABA) and zeatin) levels of corn and redroot pigweed were investigated. It was observed that all concentrations of methanol extracts of root, stem and leaf of L. draba inhibited germination, radicle and plumule elongation when compared with the respective controls. Besides this, the degree of inhibition was increased in concert with increasing concentrations of extracts used. On the other hand, phytohormone levels changed with the application of different extract concentrations. Comparing with the control, the GA levels significantly decreased while the ABA levels increased in all the application groups. Zeatin and IAA levels showed changes depending upon the applied extracts and concentrations. PMID:23293131

Kaya, Yusuf; Aksakal, Ozkan; Sunar, Serap; Erturk, Filiz Aygun; Bozari, Sedat; Agar, Guleray; Erez, Mehmet Emre; Battal, Peyami

2013-01-01

364

Influence of physico-chemical parameters of the aquatic medium on germination of Eichhornia crassipes seeds.  

PubMed

The germination of seeds of Eichhornia crassipes in locations distant from the foci of infestation may be a means of dispersal of this invasive plant. Nonetheless, no modern studies have examined the influence of single components on germination, although the influence of temperature, oxygen and redox potential was examined in earlier studies. The effects of pH, conductivity, nitrate, phosphate, potassium, calcium, iron and boron on germination of E. crassipes were determined in seed germination tests. The results showed that external input of nutrients influences germination, since neither pH nor conductivity alone had any effect, but there was a significant increase in germination in growth media containing phosphorus at 3.95 mgl(-1) (P/L; 95.5%) and boron at 10 mgl(-1) (B/L; 97.5%); at higher concentrations, the latter was toxic. These findings contribute to knowledge of factors controlling the germination of E. crassipes seeds. Consequently, E. crassipes seeds would find very good conditions for germination in water classified as hypereutrophic, which may play a decisive role in expansion of this plant. PMID:21668605

Albano Prez, E; Ruiz Tllez, T; Snchez Guzmn, J M

2011-07-01

365

Perigynium Removal Improves Seed Germination in Awl-Fruit Sedge (Carex stipata)  

Microsoft Academic Search

From our experiences, awl-fruit sedge (Carex stipata Muhl. ex Willd. [Cyperaceae]) is an easily propagated wetland plant in Washington State. Because seeds can be collected from the same growth year, germinated without stratification, and grown into plants, C. stipata can be quickly propagated during summer for fall and winter outplanting. We believed, however, that perigynium removal could improve success. We

Derrick D. Cooper; Nate Hough-Snee

2011-01-01

366

Perigynium Removal Improves Seed Germination in Awl-Fruit Sedge (Carex stipata)  

Microsoft Academic Search

:From our experiences, awl-fruit sedge (Carex stipata Muhl. ex Willd. [Cyperaceae]) is an easily propagated wetland plant in Washington State. Because seeds can be collected from the same growth year, germinated without stratification, and grown into plants, C. stipata can be quickly propagated during summer for fall and winter outplanting. We believed, however, that perigynium removal could improve success. We

Derrick D. Cooper; Nate Hough-Snee

2011-01-01

367

DISPERSAL OF WETLAND PLANT SEEDS BY MALLARDS: INFLUENCE OF GUT PASSAGE ON RECOVERY, RETENTION, AND GERMINATION  

E-print Network

mallards (Anas platyrhynchos) and collected fecal samples every 4 hours for 48 hours; all recovered seeds to different plant strategies that relate to reproductive tactics and habitat type. Key Words: Anas platyrhynchos, endozoochory, retention time, seed dispersal INTRODUCTION Seed dispersal is an important process

Dugger, Bruce

368

Allelopathic effects of water extracts of Artemisia princeps var. orientalis on selected plant species  

Microsoft Academic Search

The allelopathic effects of wormwood plants (Artemisia princeps var.orientalis) and their possible phytotoxicity on receptor species were investigated. The aqueous extracts of mature leaf, stem, and root of wormwood plants caused significant inhibition in germination and decreased seedling elongation of receptor plants, whereas germination of some species was not inhibited by extracts of stems and roots. Dry weight growth was

Bong-Seop Kil; Kyeong Won Yun

1992-01-01

369

Demonstrating the Effects of Light Quality on Plant Growth.  

ERIC Educational Resources Information Center

Describes a lab demonstration that illustrates the effect of different colors or wavelengths of visible light on plant growth and development. This demonstration is appropriate for use in college biology, botany, or plant physiology courses. (HM)

Whitesell, J. H.; Garcia, Maria

1977-01-01

370

Effect of Flashing Light on Plant Growth Rate  

Microsoft Academic Search

NUMEROUS investigations have been reported relating photosynthetic light efficiency and plant growth. Dickson1 has found in Lemna minor a growth rate decline as the length of alternating periods of light and darkness decreased, with a minimum growth rate at a 1-min light period; but at a 5-sec light period the growth rate was comparable with that under a 12-h photoperiod.

M. H. Dickson; S. E. Chua

1963-01-01

371

Promoting Effects of a Single Rhodopseudomonas palustris Inoculant on Plant Growth by Brassica rapa chinensis under Low Fertilizer Input  

PubMed Central

Several Rhodopseudomonas palustris strains have been isolated from rice paddy fields in Taiwan by combining the Winogradsky column method and molecular marker detection. These isolates were initially screened by employing seed germination and seedling vigor assays to evaluate their potential as inoculants. To fulfill the demand in the present farming system for reducing the application of chemical fertilizers, we assessed the plant growth-promoting effects of the R. palustris YSC3, YSC4, and PS3 inoculants on Brassica rapa chinensis (Chinese cabbage) cultivated under a half quantity of fertilizer. The results obtained showed that supplementation with approximately 4.0106 CFU g?1 soil of the PS3 inoculant at half the amount of fertilizer consistently produced the same plant growth potential as 100% fertility, and also increased the nitrogen use efficiency of the applied fertilizer nutrients. Furthermore, we noted that the plant growth-promotion rate elicited by PS3 was markedly higher with old seeds than with new seeds, suggesting it has the potential to boost the development of seedlings that were germinated from carry-over seeds of poor quality. These beneficial traits suggest that the PS3 isolate may serve as a potential PGPR inoculant for integrated nutrient management in agriculture. PMID:25130882

Wong, Wai-Tak; Tseng, Ching-Han; Hsu, Shu-Hua; Lur, Huu-Sheng; Mo, Chia-Wei; Huang, Chu-Ning; Hsu, Shu-Chiung; Lee, Kung-Ta; Liu, Chi-Te

2014-01-01

372

Fire intensity effects on seed germination of native and invasive Eastern deciduous forest understory plants  

Microsoft Academic Search

Low-intensity fires were important for maintaining the structure of Eastern deciduous forests (EDFs) for thousands of years before European settlement of North America, though fire suppression became a standard management practice in the 1930s. More recently, prescribed fires have been reintroduced to EDF habitats to aid in the restoration of native plant diversity, but invasions of non-native species such as

Sarah M. Emery; Joy Uwimbabazi; S. Luke Flory

2011-01-01

373

Plant growth-promoting Methylobacterium induces defense responses in groundnut (Arachis hypogaea L.) compared with rot pathogens.  

PubMed

This study, framed in two different phases, studied the plant-growth promotion and the induction of systemic resistance in groundnut by Methylobacterium. Seed imbibition with Methylobacterium sp. increased germination by 19.5% compared with controls. Combined inoculation of Methylobacterium sp. with Rhizobium sp. also significantly increased plant growth, nodulation, and yield attributes in groundnut compared with individual inoculation of Rhizobium sp. Methylobacterium sp. challenge-inoculated with Aspergillus niger/Sclerotium rolfsii in groundnut significantly enhanced germination percentage and seedling vigour and showed increased phenylalanine ammonia lyase (PAL), beta-1,3-glucanase, and peroxidase (PO) activities. Under pot-culture conditions, in Methylobacterium sp. seed-treated groundnut plants challenge-inoculated with A. niger/S. rolfsii through foliar sprays on day 30, the activities of enzymes PO, PAL, and beta-1,3-glucanase increased constantly from 24 to 72 hours, after which decreased activity was noted. Five isozymes of polyphenol oxidase and PO could be detected in Methylobacterium-treated plants challenged with A. niger/S. rolfsii. Induced systemic resistance activity in groundnut against rot pathogens in response to methylotrophic bacteria suggests the possibility that pink-pigmented facultative methylotrophic bacteria might be used as a means of biologic disease control. PMID:16941245

Madhaiyan, M; Suresh Reddy, B V; Anandham, R; Senthilkumar, M; Poonguzhali, S; Sundaram, S P; Sa, Tongmin

2006-10-01

374

Soil bacterium Bacillus subtilis (GB03) augments plant growth and volatile emissions in Eruca sativa (Arugula).  

E-print Network

??Plant growth-promoting rhizobacteria (PGPR) are naturally occurring soil microorganisms that colonize roots to stimulate plant growth and development by increasing harvest yields, plant weight, seed (more)

Chou, May Y.

2013-01-01

375

Germination of Dimorphic Seeds of the Desert Annual Halophyte Suaeda aralocaspica (Chenopodiaceae), a C4 Plant without Kranz Anatomy  

PubMed Central

Background and Aims Suaeda aralocaspica is a C4 summer annual halophyte without Kranz anatomy that is restricted to the deserts of central Asia. It produces two distinct types of seeds that differ in colour, shape and size. The primary aims of the present study were to compare the dormancy and germination characteristics of dimorphic seeds of S. aralocaspica and to develop a conceptual model of their dynamics. Methods Temperatures simulating those in the natural habitat of S. aralocaspica were used to test for primary dormancy and germination behaviour of fresh brown and black seeds. The effects of cold stratification, gibberellic acid, seed coat scarification, seed coat removal and dry storage on dormancy breaking were tested in black seeds. Germination percentage and recovery responses of brown seeds, non-treated black seeds and 8-week cold-stratified black seeds to salt stress were tested. Key Results Brown seeds were non-dormant, whereas black seeds had non-deep Type 2 physiological dormancy (PD). Germination percentage and rate of germination of brown seeds and of variously pretreated black seeds were significantly higher than those of non-pretreated black seeds. Exposure of seeds to various salinities had significant effects on germination, germination recovery and induction into secondary dormancy. A conceptual model is presented that ties these results together and puts them into an ecological context. Conclusions The two seed morphs of S. aralocaspica exhibit distinct differences in dormancy and germination characteristics. Suaeda aralocaspica is the first cold desert halophyte for which non-deep Type 2 PD has been documented. PMID:18772148

Wang, Lei; Huang, Zhenying; Baskin, Carol C.; Baskin, Jerry M.; Dong, Ming

2008-01-01

376

The plant stigma exudate: a biochemically active extracellular environment for pollen germination?  

PubMed

During sexual reproduction, pollen performance is greatly influenced by the female tissues. The stigma exudate, i.e., the extracellular secretion that covers the stigma outermost surface, has been usually regarded as a reservoir of water, secondary metabolites, cell wall precursors and compounds that serve as energy supply for rapid pollen tube growth. In an attempt to identify the proteins present in the stigma secretome, we performed a large-scale analysis in two species (Lilium longiflorum and Olea europaea) following a proteomic-based approach. The resulting data strongly suggest that the stigma exudate is not a mere storage site but also a biochemically active environment with a markedly catabolic nature. Thus, this secretion may modulate early pollen tube growth and contribute to the senescence of stigma after pollination. In addition, a putative cross-talk between genetic programs that regulate stress/defense and pollination responses in the stigma is also suggested. The stigma exudate might also functionally diverge between species on the basis on their ecology and the biochemical, morphological and anatomical features of their stigmas. Unexpectedly, we identified in both exudates some intracellular proteins, suggesting that a mechanism other than the canonical ER-Golgi exocytic pathway may exist in the stigma and contribute to exudate secretion. PMID:24589550

Rejn, Juan David; Delalande, Franois; Schaeffer-Reiss, Christine; Carapito, Christine; Zienkiewicz, Krzysztof; de Dios Alch, Juan; Isabel Rodrguez-Garca, Mara; Van Dorsselaer, Alain; Castro, Antonio J

2014-01-01

377

Interchangeable effects of gibberellic acid and temperature on embryo growth, seed germination and epicotyl emergence in Ribes multiflorum ssp. sandalioticum (Grossulariaceae).  

PubMed

Morphophysiological dormancy was investigated in seeds of Ribes multiflorum Kit ex Roem et Schult. ssp. sandalioticum Arrigoni, a rare mountain species endemic to Sardinia (Italy). There were no differences in imbibition rates between intact and scarified seeds, suggesting a lack of physical dormancy, while methylene blue solution (0.5%) highlighted a preferential pathway for solution entrance through the raphe. Embryos were small at seed dispersal, with an initial embryo:seed ratio (E:S) of ca. 0.2 (embryo length, ca. 0.5 mm), whereas the critical E:S ratio for germination was three times longer (ca. 0.6). Gibberellic acid (GA(3), 250 mg l(-1)) and warm stratification (25 C for 3 months) followed by low temperature (<15 C) enhanced embryo growth rate (maximum of ca. 0.04 mm day(-1) at 10 C) and subsequent seed germination (radicle emergence; ca. 80% at 10 C). Low germination occurred at warmer temperatures, and cold stratification (5 C for 3 months) induced secondary dormancy. After radicle emergence, epicotyl emergence was delayed for ca. 2 months for seeds from three different populations. Mean time of epicotyl emergence was affected by GA(3) . Seeds of this species showed non-deep simple (root) - non-deep simple (epicotyl) morphophysiological dormancy, highlighting a high synchronisation with Mediterranean seasonality in all the investigated populations. PMID:21972981

Mattana, E; Pritchard, H W; Porceddu, M; Stuppy, W H; Bacchetta, G

2012-01-01

378

Efficiency of plant growth-promoting rhizobacteria (PGPR) for the enhancement of rice growth  

Microsoft Academic Search

Plant growth-promoting rhizobacteria (PGPR) are beneficial bacteria that colonize plant roots and enhance plant growth by a wide variety of mechanisms. The use of PGPR is steadily increasing in agriculture and offers an attractive way to replace chemical fertilizers, pesticides, and supplements. Here, we have isolated and characterized the PGPR from the rhizosphere soil of rice field for the enhancement

M. Ashrafuzzaman; Farid Akhtar Hossen; M. Razi Ismail; M. Zahurul Islam; S. M. Shahidullah; Sariah Meon

2009-01-01

379

THERMAL RADIATION LOAD ON TEMPERATURE REGIMES IN PLANT GROWTH CHAMBERS  

Microsoft Academic Search

HAMASAKI T. and OKADA M. Thermal radiation load on temperature regimes in plant growth chambers. BIOTRONICS 29, 57-69, 2000. In enclosed environments such as a plant growth chamber, thermal radiation plays an important role in determining heat balance and therefore the resultant temperature regimes. In artificially illuminated chambers, a significant level of thermal radiation is emitted from the lamps and\\/or

T. HAMASAKI; M. OKADA

2000-01-01

380

Applications of free living plant growth-promoting rhizobacteria  

Microsoft Academic Search

Free-living plant growth-promoting rhizobacteria (PGPR) can be used in a variety of ways when plant growth enhancements are required. The most intensively researched use of PGPR has been in agriculture and horticulture. Several PGPR formulations are currently available as commercial products for agricultural production. Recently developing areas of PGPR usage include forest regeneration and phytoremediation of contaminated soils. As the

M. Lucy; E. Reed; Bernard R. Glick

2004-01-01

381

Do soil protozoa enhance plant growth by hormonal effects?  

Microsoft Academic Search

We investigated changes in root morphology of watercress seedlings (Lepidium sativum L.) and effects on the composition of the rhizosphere bacterial community to test the hypothesis that rhizosphere protozoa affect plant growth by a grazing-induced stimulation of plant growth-promoting rhizobacteria. The presence of Acanthamoebae (Protozoa: Amoebida) induced changes in root morphology of watercress seedlings as soon as the root protruded

M. Bonkowski; F. Brandt

2002-01-01

382

Plant growth regulators and virus infection: A critical review  

Microsoft Academic Search

Virus infection can severely inhibit plant growth and distort development. This article reviews changes in plant growth regulator metabolism caused by infection. In general, virus infection decreases auxin and gibberellin concentrations and increases abscisic acid concentration. Ethylene production is stimulated in necrotic or chlorotic reactions to infection, but not where the virus spreads systemically without necrosis. While these broad trends

R. S. S. Fraser; R. J. Whenham

1982-01-01

383

The Effect of ?-Amanitin on the Arabidopsis Seed Proteome Highlights the Distinct Roles of Stored and Neosynthesized mRNAs during Germination1  

PubMed Central

To investigate the role of stored and neosynthesized mRNAs in seed germination, we examined the effect of ?-amanitin, a transcriptional inhibitor targeting RNA polymerase II, on the germination of nondormant Arabidopsis seeds. We used transparent testa mutants, of which seed coat is highly permeable, to better ascertain that the drug can reach the embryo during seed imbibition. Even with the most permeable mutant (tt2-1), germination (radicle protrusion) occurred in the absence of transcription, while subsequent seedling growth was blocked. In contrast, germination was abolished in the presence of the translational inhibitor cycloheximide. Taken together, the results highlight the role of stored proteins and mRNAs for germination in Arabidopsis and show that in this species the potential for germination is largely programmed during the seed maturation process. The ?-amanitin-resistant germination exhibited characteristic features. First, this germination was strongly slowed down, indicating that de novo transcription normally allows the synthesis of factor(s) activating the germination rate. Second, the sensitivity of germination to gibberellic acid was reduced 15-fold, confirming the role of this phytohormone in germination. Third, de novo synthesis of enzymes involved in reserve mobilization and resumption of metabolic activity was repressed, thus accounting for the failure in seedling establishment. Fourth, germinating seeds can recapitulate at least part of the seed maturation program, being capable of using mRNAs stored during development. Thus, commitment to germination and plant growth requires transcription of genes allowing the imbibed seed to discriminate between mRNAs to be utilized in germination and those to be destroyed. PMID:15047896

Rajjou, Loic; Gallardo, Karine; Debeaujon, Isabelle; Vandekerckhove, Joel; Job, Claudette; Job, Dominique

2004-01-01

384

The effect of pre-emergent herbicides on germination and early growth of broadleaved species used for direct seeding  

Microsoft Academic Search

Summary Weed control is essential for successful new woodland creation by direct seeding, particularly in the first year after germination. Currently, herbicides probably offer the most practical way of achieving this in UK conditions, although successful direct seeding offers the potential for reductions in total overall herbicide use compared with conventional establishment using transplants. There is a need to identify

IAN WILLOUGHBY; DAVID CLAY; FIONA DIXON

2003-01-01

385

Germination and seedling growth of the water cress Rorippa sp. exposed to the chelant [ S, S]-EDDS  

Microsoft Academic Search

With the implementation of the new EU environmental framework directives, high tier risk assessments of chemicals will be increasingly needed. For high production chemicals, additional tests will complement the standard battery for aquatic toxicity assessments (daphnids, algae, and fish). In the context of a new chemical notification at the European Union level, we have developed a seed germination and root

Ali Temara; Tim Bowmer; Andre Rottiers; Steve Robertson

2006-01-01

386

Influence of organic and inorganic soil amendments on plant growth in crude oil-contaminated soil.  

PubMed

Phytoremediation can be a viable alternative to traditional, more costly remediation techniques. Three greenhouse studies were conducted to evaluate plant growth with different soil amendments in crude oil-contaminated soil. Growth of alfalfa (Medicago sativa L., cultivar: Riley), bermudagrass (Cynodon dactylon L., cultivar: Common), crabgrass (Digitaria sanguinalis, cultivar: Large), fescue (Lolium arundinaceum Schreb., cultivar: Kentucky 31), and ryegrass (Lolium multiflorum Lam., cultivar: Marshall) was determined in crude oil-contaminated soil amended with either inorganic fertilizer, hardwood sawdust, papermill sludge, broiler litter or unamended (control). In the first study, the addition of broiler litter reduced seed germination for ryegrass, fescue, and alfalfa. In the second study, bermudagrass grown in broiler litter-amended soil produced the most shoot biomass, bermudagrass produced the most root biomass, and crabgrass and bermudagrass produced the most root length. In the third study, soil amended with broiler litter resulted in the greatest reduction in gravimetric total petroleum hydrocarbon (TPH) levels across the six plant treatments following the 14-wk study. Ryegrass produced more root biomass than any other species when grown in inorganic fertilizer- or hardwood sawdust + inorganic fertilizer-amended soil. The studies demonstrated that soil amendments and plant species selection were important considerations for phytoremediation of crude oil-contaminated soil. PMID:14750564

White, P M; Wolf, D C; Thoma, G J; Reynolds, C M

2003-01-01

387

Beneficial Rhizobacteria Induce Plant Growth: Mapping Signaling Networks in Arabidopsis  

Microsoft Academic Search

\\u000a The survival of soil microorganisms is largely dependent upon growth and productivity of the plant community. Plants not only\\u000a supply organic matter for decomposers, but also release up to 30% of their photosynthetic output in the form of root exudates\\u000a that attract and maintain fungal and bacterial soil colonies. Plant growth-promoting rhizobacteria (PGPR) are naturally occurring\\u000a microbes that colonize roots

Paul W. Par; Huiming Zhang; Mina Aziz; Xitao Xie; Mi-Seong Kim; Xin Shen; Jinlin Zhang

388

USE OF MARSH PLANTS FOR TOXICITY TESTING OF WATER AND SEDIMENT  

EPA Science Inventory

The freshwater wetland plants, Echinochlo crusgalli crusgalli andEchinocloa crusgalli zelayensis, and the saltmarsh plant, Spartina alterniflora, were exposed to the herbicides, metolachlor and norflurazon, in two types of toxicity tests: eed germination and early seedling growth...

389

Light Plants and Dark Plants, Wet Plants and Dry Ones  

NSDL National Science Digital Library

Students plant sunflower seeds in plastic cups, and once germinated, expose them to varying light or soil moisture conditions. They measure growth of the seedlings every few days using non-standard measurement (inch cubes). After a few weeks, they compare the growth of plants exposed to the different conditions and make bar comparative graphs, which they analyze to draw conclusions about the needs of plants.

Engineering K-Phd Program

390

Herbivory: effects on plant abundance, distribution and population growth  

Microsoft Academic Search

Plants are attacked by many different consumers. A critical question is how often, and under what conditions, common reductions in growth, fecundity or even survival that occur due to herbivory translate to meaningful impacts on abundance, distribution or dynamics of plant populations. Here, we review population-level studies of the effects of consumers on plant dynamics and evaluate: (i) whether particular

John L. Maron; Elizabeth Crone

2006-01-01

391

Insights of the fluorescent pseudomonads in plant growth regulation  

Microsoft Academic Search

Environmental concerns have led to the need of sus- tainable use of natural resources. Plants constitute an excellent ecosystem for microorganisms that interact with plant tissues and cells with differing degrees of dependence. Studies on the relationship between roots and microbiota are essential to achieve viable agricul- tural applications. Plant growth-promoting rhizobac- teria are employed as inoculants for biofertilization, phytostimulation

Devendra Kumar Choudhary; Anil Prakash; Victor Wray; Bhavdish N. Johri

2009-01-01

392

Plant growth promotion in cereal and leguminous agricultural important plants: from microorganism capacities to crop production.  

PubMed

Plant growth-promoting rhizobacteria (PGPR) are free-living bacteria which actively colonize plant roots, exerting beneficial effects on plant development. The PGPR may (i) promote the plant growth either by using their own metabolism (solubilizing phosphates, producing hormones or fixing nitrogen) or directly affecting the plant metabolism (increasing the uptake of water and minerals), enhancing root development, increasing the enzymatic activity of the plant or "helping" other beneficial microorganisms to enhance their action on the plants; (ii) or may promote the plant growth by suppressing plant pathogens. These abilities are of great agriculture importance in terms of improving soil fertility and crop yield, thus reducing the negative impact of chemical fertilizers on the environment. The progress in the last decade in using PGPR in a variety of plants (maize, rice, wheat, soybean and bean) along with their mechanism of action are summarized and discussed here. PMID:24144612

Prez-Montao, F; Alas-Villegas, C; Bellogn, R A; del Cerro, P; Espuny, M R; Jimnez-Guerrero, I; Lpez-Baena, F J; Ollero, F J; Cubo, T

2014-01-01

393

Signals and Mechanisms in the Control of Plant Growth  

Microsoft Academic Search

Plant growth is mediated by three fundamental processes: cell growth, division, and expansion. The\\u000a mechanistic analysis of their contributions are complicated by the observation that the balance of their\\u000a contributions to organ growth are not hard-wired. Reduced cell proliferation, irrespective of whether this\\u000a is caused by decreased cell growth or diminished cell division, can be, at least partially, compensated\\u000a for

Peter Doerner

394

Germin and Germin-like Proteins: Evolution, Structure, and Function  

Microsoft Academic Search

Germin and germin-like proteins (GLPs) are encoded by a family of genes found in all plants. They are part of the cupin superfamily of biochemically diverse proteins, a superfamily that has a conserved tertiary structure, though with limited similarity in primary sequence. The subgroups of GLPs have different enzyme functions that include the two hydrogen peroxidegenerating enzymes, oxalate oxidase (OxO)

Jim M. Dunwell; J. George Gibbings; Tariq Mahmood; S. M. Saqlan Naqvi

2008-01-01

395

State-of-the-art plant growth chamber for conducting commercial plant research in microgravity  

NASA Astrophysics Data System (ADS)

Conduct of plant research to assess the impact of microgravity on plant growth and development requires a plant growth unit that has the capability to provide totally controlled environment in the plant chamber. Since plants are sensitive to a number of atmospheric gaseous materials, the plant chamber atmosphere must be isolated from the space vehicle atmosphere and the plant growth unit must also be capable of removing any deleterious materials that may impact plant growth and development. Advanced ASTROCULTURE (ADVASC), a space-based plant growth unit based on proven ASTROCULTURE technology, has been developed by the Wisconsin Center for Space Automation and Robotics (WCSAR) at the University of Wisconsin-Madison to take advantage of plant research opportunities during the early assembly phase of International Space Station (ISS) when ISS resources and up/down mass availability would be very limited. ADVASC provides a completely enclosed, environmentally controlled plant growth chamber to support commercially oriented and/or fundamental plant research for time duration of several months in reduced gravity environment. .

Zhou, Weijia; Falk, Paul

2000-01-01

396

Polyamines, IAA and ABA during germination in two recalcitrant seeds: Araucaria angustifolia (Gymnosperm) and Ocotea odorifera (Angiosperm)  

PubMed Central

Background and Aims Plant growth regulators play an important role in seed germination. However, much of the current knowledge about their function during seed germination was obtained using orthodox seeds as model systems, and there is a paucity of information about the role of plant growth regulators during germination of recalcitrant seeds. In the present work, two endangered woody species with recalcitrant seeds, Araucaria angustifolia (Gymnosperm) and Ocotea odorifera (Angiosperm), native to the Atlantic Rain Forest, Brazil, were used to study the mobilization of polyamines (PAs), indole-acetic acid (IAA) and abscisic acid (ABA) during seed germination. Methods Data were sampled from embryos of O. odorifera and embryos and megagametophytes of A. angustifolia throughout the germination process. Biochemical analyses were carried out in HPLC. Key Results During seed germination, an increase in the (Spd + Spm) : Put ratio was recorded in embryos in both species. An increase in IAA and PA levels was also observed during seed germination in both embryos, while ABA levels showed a decrease in O. odorifera and an increase in A. angustifolia embryos throughout the period studied. Conclusions The (Spd + Spm) : Put ratio could be used as a marker for germination completion. The increase in IAA levels, prior to germination, could be associated with variations in PA content. The ABA mobilization observed in the embryos could represent a greater resistance to this hormone in recalcitrant seeds, in comparison to orthodox seeds, opening a new perspective for studies on the effects of this regulator in recalcitrant seeds. The gymnosperm seed, though without a connective tissue between megagametophyte and embryo, seems to be able to maintain communication between the tissues, based on the likely transport of plant growth regulators. PMID:21685432

Pieruzzi, Fernanda P.; Dias, Leonardo L. C.; Balbuena, Tiago S.; Santa-Catarina, Claudete; dos Santos, Andre L. W.; Floh, Eny I. S.

2011-01-01

397

Effects of real or simulated microgravity on plant cell growth and proliferation  

Microsoft Academic Search

Experiments on seed germination and seedling growth performed in real microgravity on the International Space Station and in different facilities for simulating microgravity in Earth-based laboratories (Random Positioning Machine and Magnetic Levitation), have provided evidence that the absence of gravity (or the artificial compensation of the gravity vector) results in the uncoupling of cell growth and proliferation in root meristematic

Francisco Javier Medina; Ana Isabel Manzano; Raul Herranz; Camelia Dijkstra; Oliver Larkin; Richard Hill; Eugnie Carnero-Daz; Jack J. W. A. van Loon; Paul Anthony; Michael R. Davey; Laurence Eaves

2010-01-01

398

The Effects of Bio-priming with PGPR on Germination of Radish (Raphanus sativus L.) Seeds under Saline Conditions  

Microsoft Academic Search

The present study was conducted to examine the effects of bio-priming with plant growth promoting rhizobacteria (PGPR) on the germination of radish (Raphanus sativus L.) seeds under different saline (NaCl) conditions. Three radish cultivars ('Antep', 'Beyaz', and 'Siyah') were used as plant material and 5 bacteria strains (Agrobacterium rubi strain A 16, Burkholderia gladii strain BA 7, Pseudomonas putida strain

Haluk a?lar KAYMAK; Faika YARALI; Mesude Figen DNMEZ

399

Expert System Control of Plant Growth in an Enclosed Space  

NASA Technical Reports Server (NTRS)

The Expert System is an enclosed, controlled environment for growing plants, which incorporates a computerized, knowledge-based software program that is designed to capture the knowledge, experience, and problem-solving skills of one or more human experts in a particular discipline. The Expert System is trained to analyze crop/plant status, to monitor the condition of the plants and the environment, and to adjust operational parameters to optimize the plant-growth process. This system is intended to provide a way to remotely control plant growth with little or no human intervention. More specifically, the term control implies an autonomous method for detecting plant states such as health (biomass) or stress and then for recommending and implementing cultivation and/or remediation to optimize plant growth and to minimize consumption of energy and nutrients. Because of difficulties associated with delivering energy and nutrients remotely, a key feature of this Expert System is its ability to minimize this effort and to achieve optimum growth while taking into account the diverse range of environmental considerations that exist in an enclosed environment. The plant-growth environment for the Expert System could be made from a variety of structures, including a greenhouse, an underground cavern, or another enclosed chamber. Imaging equipment positioned within or around the chamber provides spatially distributed crop/plant-growth information. Sensors mounted in the chamber provide data and information pertaining to environmental conditions that could affect plant development. Lamps in the growth environment structure supply illumination, and other additional equipment in the chamber supplies essential nutrients and chemicals.

May, George; Lanoue, Mark; Bathel, Matthew; Ryan, Robert E.

2008-01-01

400

Respiratory Transition during Seed Germination 1  

PubMed Central

Experiments with germinating seeds of Wayne soybean (Glycine max Merr.) show that between the 4th and the 8th hour of germination, respiration experiences a transition from predominantly alternate respiration, which is sensitive to salicylhydroxamic acid, to a cyanide-sensitive respiration. The dependence of early germination stages on alternate respiration is reflected in several types of seed functions, including subsequent root growth rate, chlorophyll synthesis, and germination itself. The early period of germination is shown to require a normal O2 tension, which is no longer a requirement at later stages. The changing sensitivity to cyanide and to salicylhydroxamic acid is found to be common to seven different types of germinating seeds. It is proposed that the alternate pathway of respiration provides something essential for the completion of the earliest stages of seed germination. PMID:16659465

Yentur, Semahat; Leopold, A. Carl

1976-01-01

401

Influence of inoculation with plant growth promoting rhizobacteria (PGPR) on tomato plant growth and nematode reproduction under greenhouse conditions.  

PubMed

Numerous species of soil bacteria which flourish in the rhizosphere of plants or around plant tissues stimulate plant growth and reduce nematode population by antagonistic behavior. These bacteria are collectively known as PGPR (plant growth promoting rhizobacteria). The effects of six isolates of PGPR Pseudomonas putida, Pseudomonas fluorescens, Serratia marcescens, Bacillus amyloliquefaciens, Bacillus subtilis and Bacillus cereus, were studied on tomato plant growth and root knot nematode reproduction after 45days from nematode infection. The highest number of shoot dry weight/g (43.00g) was detected in the plant treated with S. marcescens; then P. putida (34.33g), B. amyloliquefaciens (31.66g), P. fluorescens (30.0g), B. subtilis (29.0g), B. cereus (27.0g) and nematode alone (untreated) 20g/plant. While the highest number of plant height was observed when plant was treated with S. marcescens, P. fluorescens, P. putida, B. amyloliquefaciens and P. putida 52.66, 50.66, 48 and 48cm respectively. No significant differences were seen between previous treatments but only had significant differences compared with untreated plant. The highest number of fruit/plant was observed when plants were treated with S. marcescens (10.66), then B. amyloliquefaciens (8.66), P. putida (8), P. fluorescens (8) and B. cereus (7.66). No significant differences between the last 4 treatments, but all had significant differences compared with untreated plants. The highest weight of plant yield (g) was observed with S. marcescens (319.6g/plant) and the lowest weight of plant yield was observed in plants treated with nematode alone (untreated). On the other hand, the lowest numbers of J2/10g of soil (78), galls/root, (24.33) galls/root, egg masses/root (12.66) and egg/egg masses were observed in the plants treated with S. marcescens. PMID:23961220

Almaghrabi, Omar A; Massoud, Samia I; Abdelmoneim, Tamer S

2013-01-01

402

Rape (Brassica chinensis L.) seed germination, seedling growth, and physiology in soil polluted with di-n-butyl phthalate and bis(2-ethylhexyl) phthalate.  

PubMed

Phthalic acid esters (PAEs) pollution in agricultural soils caused by widely employed plastic products is becoming more and more widespread in China. PAEs polluted soil can lead to phytotoxicity in higher plants and potential health risks to human being. We evaluated the individual toxicity of di-n-butyl phthalate (DnBP) and bis(2-ethylhexyl) phthalate (DEHP), two representative PAEs, to sown rape (Brassica chinensis L.) seeds within 72 h (as germination stage) and seedlings after germination for 14 days by monitoring responses and trends of different biological parameters. No significant effects of six concentrations of PAE ranging from 0 (not treated/NT) to 500 mg?kg(-1) on germination rate in soil were observed. However, root length, shoot length, and biomass (fresh weight) were inhibited by both pollutants (except root length and biomass under DEHP). Stimulatory effects of both target pollutants on malondialdehyde (MDA) content, superoxide dismutase (SODase) activity, ascorbate peroxidase (APXase) content, and polyphenoloxidase (PPOase) activity in shoots and roots (SODase activity in shoots excluded) were in the same trend with the promotion of proline (Pro) but differed with acetylcholinesterase activity (except in shoots under DnBP) for analyzed samples treated for 72 h and 14 days. Responses of representative storage compounds free amino acids (FAA) and total soluble sugar (TSS) under both PAEs were raised. Sensitivity of APXase and Pro in roots demonstrates their possibility in estimation of PAE phytotoxicity and the higher toxicity of DnBP, which has also been approved by the morphological photos of seedlings at day 14. Higher sensitivity of the roots was also observed. The recommended soil allowable concentration is 5 mg DnBP?kg(-1) soil for the development of rape. We still need to know the phytotoxicity of DEHP at whole seedling stage for both the growing and development; on the other hand, soil criteria for PAE compounds are urgently required in China. PMID:23389857

Ma, Tingting; Christie, Peter; Teng, Ying; Luo, Yongming

2013-08-01

403

Tubular Membrane Plant-Growth Unit  

NASA Technical Reports Server (NTRS)

Hydroponic system controls nutrient solution for growing crops in space. Pump draws nutrient solution along inside of tubular membrane in pipe from reservoir, maintaining negative pressure in pipe. Roots of plants in slot extract nutrient through membrane within pipe. Crop plants such as wheat, rice, lettuce, tomatoes, soybeans, and beans grown successfully with system.

Dreschel, Thomas W.

1992-01-01

404

Plant growth-promoting rhizobacteria and root system functioning.  

PubMed

The rhizosphere supports the development and activity of a huge and diversified microbial community, including microorganisms capable to promote plant growth. Among the latter, plant growth-promoting rhizobacteria (PGPR) colonize roots of monocots and dicots, and enhance plant growth by direct and indirect mechanisms. Modification of root system architecture by PGPR implicates the production of phytohormones and other signals that lead, mostly, to enhanced lateral root branching and development of root hairs. PGPR also modify root functioning, improve plant nutrition and influence the physiology of the whole plant. Recent results provided first clues as to how PGPR signals could trigger these plant responses. Whether local and/or systemic, the plant molecular pathways involved remain often unknown. From an ecological point of view, it emerged that PGPR form coherent functional groups, whose rhizosphere ecology is influenced by a myriad of abiotic and biotic factors in natural and agricultural soils, and these factors can in turn modulate PGPR effects on roots. In this paper, we address novel knowledge and gaps on PGPR modes of action and signals, and highlight recent progress on the links between plant morphological and physiological effects induced by PGPR. We also show the importance of taking into account the size, diversity, and gene expression patterns of PGPR assemblages in the rhizosphere to better understand their impact on plant growth and functioning. Integrating mechanistic and ecological knowledge on PGPR populations in soil will be a prerequisite to develop novel management strategies for sustainable agriculture. PMID:24062756

Vacheron, Jordan; Desbrosses, Guilhem; Bouffaud, Marie-Lara; Touraine, Bruno; Monne-Loccoz, Yvan; Muller, Daniel; Legendre, Laurent; Wisniewski-Dy, Florence; Prigent-Combaret, Claire

2013-01-01

405

Epidermal Signalling and the Control of Plant Shoot Growth  

Microsoft Academic Search

Although the epidermal cell-layer is of undisputed physiological importance to all angiosperms, its\\u000a potential role in controlling the growth of plant organs has remained asubject of research and contention\\u000a for more than acentury. Recent advances in our understanding of the molecular control of plant cell\\u000a proliferation, growth and specification, in combination with novel biotechnological techniques, have provided\\u000a new tools for

Gwyneth C. Ingram

406

Plant-growth Lighting for Advanced Life Support: A Review  

Microsoft Academic Search

35 pages\\u000aProvider Notes:Lighting is a critical concern for plant growth in an Advanced Life-support System (ALS). Electric lighting is energy intensive, but it is necessary when balanced against the hazards and limitations of plant growth under natural sunlight on the surface of the moon or Mars. The characteristics of different electric light types are reviewed, and functionality for an

Gioia Donna Massa; Cary A. Mitchell

2006-01-01

407

The class IId bacteriocin thuricin-17 increases plant growth.  

PubMed

The mechanisms by which many plant growth promoting rhizobacteria (PGPR) affect plants are unknown. We recently isolated a rhizosphere bacterium (Bacillus thuringiensis NEB17), that promotes soybean growth and screened the liquid growth medium in which it grew for plant growth stimulating materials. We have also shown that it produces a bacteriocin (named by us as thuricin-17 and a member of the recently described class IId bacteriocins). Here we show that application of this bacteriocin to leaves (spray) or roots (drench) directly stimulates the growth of both a C(3) dicot (soybean) and a C(4) monocot (corn). This growth stimulation is similar in nature to that previously seen when plants are treated with Nod factors. Strain NEB17 contains three copies of the gene for thuricin 17 that code for identical amino acid sequences. These two lines of evidence suggest that the dual functions of these proteins may have constrained their evolution. This is the first report of direct plant growth enhancement by a bacteriocin. PMID:19083012

Lee, Kyung Dong; Gray, Elizabeth J; Mabood, Fazli; Jung, Woo-Jin; Charles, Trevor; Clark, Scott R D; Ly, Anh; Souleimanov, Alfred; Zhou, Xiaomin; Smith, Donald Lawrence

2009-03-01

408

Plant Growth and Morphogenesis under Different Gravity Conditions: Relevance to Plant Life in Space.  

PubMed

The growth and morphogenesis of plants are entirely dependent on the gravitational acceleration of earth. Under microgravity conditions in space, these processes are greatly modified. Recent space experiments, in combination with ground-based studies, have shown that elongation growth is stimulated and lateral expansion suppressed in various shoot organs and roots under microgravity conditions. Plant organs also show automorphogenesis in space, which consists of altered growth direction and spontaneous curvature in the dorsiventral (back and front) directions. Changes in cell wall properties are responsible for these modifications of growth and morphogenesis under microgravity conditions. Plants live in space with interesting new sizes and forms. PMID:25370193

Hoson, Takayuki

2014-01-01

409

Plant Growth and Morphogenesis under Different Gravity Conditions: Relevance to Plant Life in Space  

PubMed Central

The growth and morphogenesis of plants are entirely dependent on the gravitational acceleration of earth. Under microgravity conditions in space, these processes are greatly modified. Recent space experiments, in combination with ground-based studies, have shown that elongation growth is stimulated and lateral expansion suppressed in various shoot organs and roots under microgravity conditions. Plant organs also show automorphogenesis in space, which consists of altered growth direction and spontaneous curvature in the dorsiventral (back and front) directions. Changes in cell wall properties are responsible for these modifications of growth and morphogenesis under microgravity conditions. Plants live in space with interesting new sizes and forms. PMID:25370193

Hoson, Takayuki

2014-01-01

410

An exocyst complex functions in plant cell growth in Arabidopsis and tobacco.  

PubMed

The exocyst, an octameric tethering complex and effector of Rho and Rab GTPases, facilitates polarized secretion in yeast and animals. Recent evidence implicates three plant homologs of exocyst subunits (SEC3, SEC8, and EXO70A1) in plant cell morphogenesis. Here, we provide genetic, cell biological, and biochemical evidence that these and other predicted subunits function together in vivo in Arabidopsis thaliana. Double mutants in exocyst subunits (sec5 exo70A1 and sec8 exo70A1) show a synergistic defect in etiolated hypocotyl elongation. Mutants in exocyst subunits SEC5, SEC6, SEC8, and SEC15a show defective pollen germination and pollen tube growth phenotypes. Using antibodies directed against SEC6, SEC8, and EXO70A1, we demonstrate colocalization of these proteins at the apex of growing tobacco pollen tubes. The SEC3, SEC5, SEC6, SEC8, SEC10, SEC15a, and EXO70 subunits copurify in a high molecular mass fraction of 900 kD after chromatographic fractionation of an Arabidopsis cell suspension extract. Blue native electrophoresis confirmed the presence of SEC3, SEC6, SEC8, and EXO70 in high molecular mass complexes. Finally, use of the yeast two-hybrid system revealed interaction of Arabidopsis SEC3a with EXO70A1, SEC10 with SEC15b, and SEC6 with SEC8. We conclude that the exocyst functions as a complex in plant cells, where it plays important roles in morphogenesis. PMID:18492870

Hla, Michal; Cole, Rex; Synek, Luks; Drdov, Edita; Pecenkov, Tamara; Nordheim, Alfred; Lamkemeyer, Tobias; Madlung, Johannes; Hochholdinger, Frank; Fowler, John E; Zrsk, Viktor

2008-05-01

411

An Exocyst Complex Functions in Plant Cell Growth in Arabidopsis and Tobacco[W  

PubMed Central

The exocyst, an octameric tethering complex and effector of Rho and Rab GTPases, facilitates polarized secretion in yeast and animals. Recent evidence implicates three plant homologs of exocyst subunits (SEC3, SEC8, and EXO70A1) in plant cell morphogenesis. Here, we provide genetic, cell biological, and biochemical evidence that these and other predicted subunits function together in vivo in Arabidopsis thaliana. Double mutants in exocyst subunits (sec5 exo70A1 and sec8 exo70A1) show a synergistic defect in etiolated hypocotyl elongation. Mutants in exocyst subunits SEC5, SEC6, SEC8, and SEC15a show defective pollen germination and pollen tube growth phenotypes. Using antibodies directed against SEC6, SEC8, and EXO70A1, we demonstrate colocalization of these proteins at the apex of growing tobacco pollen tubes. The SEC3, SEC5, SEC6, SEC8, SEC10, SEC15a, and EXO70 subunits copurify in a high molecular mass fraction of 900 kD after chromatographic fractionation of an Arabidopsis cell suspension extract. Blue native electrophoresis confirmed the presence of SEC3, SEC6, SEC8, and EXO70 in high molecular mass complexes. Finally, use of the yeast two-hybrid system revealed interaction of Arabidopsis SEC3a with EXO70A1, SEC10 with SEC15b, and SEC6 with SEC8. We conclude that the exocyst functions as a complex in plant cells, where it plays important roles in morphogenesis. PMID:18492870

Hala, Michal; Cole, Rex; Synek, Lukas; Drdova, Edita; Pecenkova, Tamara; Nordheim, Alfred; Lamkemeyer, Tobias; Madlung, Johannes; Hochholdinger, Frank; Fowler, John E.; Zarsky, Viktor

2008-01-01

412

The Pseudomonas aeruginosa antimetabolite L-2-amino-4-methoxy-trans-3-butenoic acid inhibits growth of Erwinia amylovora and acts as a seed germination-arrest factor.  

PubMed

The Pseudomonas aeruginosa antimetabolite L-2-amino-4-methoxy-trans-3-butenoic acid (AMB) shares biological activities with 4-formylaminooxyvinylglycine, a related molecule produced by Pseudomonas fluorescens WH6. We found that culture filtrates of a P.?aeruginosa strain overproducing AMB weakly interfered with seed germination of the grassy weed Poa annua and strongly inhibited growth of Erwinia amylovora, the causal agent of the devastating orchard crop disease known as fire blight. AMB was active against a 4-formylaminooxyvinylglycine-resistant isolate of E.?amylovora, suggesting that the molecular targets of the two oxyvinylglycines in Erwinia do not, or not entirely, overlap. The AMB biosynthesis and transport genes were shown to be organized in two separate transcriptional units, ambA and ambBCDE, which were successfully expressed from IPTG-inducible tac promoters in the heterologous host P.?fluorescens CHA0. Engineered AMB production enabled this model biocontrol strain to become inhibitory against E.?amylovora and to weakly interfere with the germination of several graminaceous seeds. We conclude that AMB production requires no additional genes besides ambABCDE and we speculate that their expression in marketed fire blight biocontrol strains could potentially contribute to disease control. PMID:23757135

Lee, Xiaoyun; Azevedo, Mark D; Armstrong, Donald J; Banowetz, Gary M; Reimmann, Cornelia

2013-02-01

413

Magnetic field effects on plant growth, development, and evolution.  

PubMed

The geomagnetic field (GMF) is a natural component of our environment. Plants, which are known to sense different wavelengths of light, respond to gravity, react to touch and electrical signaling, cannot escape the effect of GMF. While phototropism, gravitropism, and tigmotropism have been thoroughly studied, the impact of GMF on plant growth and development is not well-understood. This review describes the effects of altering magnetic field (MF) conditions on plants by considering plant responses to MF values either lower or higher than those of the GMF. The possible role of GMF on plant evolution and the nature of the magnetoreceptor is also discussed. PMID:25237317

Maffei, Massimo E

2014-01-01

414

Magnetic field effects on plant growth, development, and evolution  

PubMed Central

The geomagnetic field (GMF) is a natural component of our environment. Plants, which are known to sense different wavelengths of light, respond to gravity, react to touch and electrical signaling, cannot escape the effect of GMF. While phototropism, gravitropism, and tigmotropism have been thoroughly studied, the impact of GMF on plant growth and development is not well-understood. This review describes the effects of altering magnetic field (MF) conditions on plants by considering plant responses to MF values either lower or higher than those of the GMF. The possible role of GMF on plant evolution and the nature of the magnetoreceptor is also discussed.

Maffei, Massimo E.

2014-01-01

415

Growth and element uptake of woody plants on flyash  

Microsoft Academic Search

Autumn olive and cherry olive plants can be established on acidic to neutral flyash disposal areas. European black alder grows rapidly, but overall survival is poor. Sawtooth oak survives well, but early growth is slow. Sycamore and shrub dogwoods show fair to moderate survival, but dieback and poor early growth are common. Application of 10 cm of subsoil to flyash

David H. Scanlon; J. Carroll Duggan

1979-01-01

416

Plant physiology Growth and photosynthesis of Gossypium hirsutum L  

E-print Network

Plant physiology Growth and photosynthesis of Gossypium hirsutum L at high photon flux densities dry weight (28-55%), but did not have any impact on FV/FM and the pigment content of the leaves hirsutum = cotton I growth reduction I night temperature I photosynthesis I soil temperature Résumé &mdash

Paris-Sud XI, Université de

417

Plant Growth-Promoting Bacteria for Phytostabilization of Mine Tailings  

Microsoft Academic Search

Eolian dispersion of mine tailings in arid and semiarid environments is an emerging global issue for which economical remediation alternatives are needed. Phytostabilization, the revegetation of these sites with native plants, is one such alternative. Revegetation often requires the addition of bulky amendments such as compost which greatly increases cost. We report the use of plant growth-promoting bacteria (PGPB) to

C. J. Grandlic; M. O. Mendez; J. Chorover; B. Machado; R. M. Maier

2009-01-01

418

Light-Regulated Plant Growth and Development  

Microsoft Academic Search

Plants are sessile and photo-autotrophic; their entire life cycle is thus strongly influenced by the ever-changing light environment. In order to sense and respond to those fluctuating conditions higher plants possess several families of photoreceptors that can monitor light from UV-B to the near infrared (far-red). The molecular nature of UV-B sensors remains unknown, red (R) and far-red (FR) light

Chitose Kami; Sverine Lorrain; Patricia Hornitschek; Christian Fankhauser

2010-01-01

419

6.0 GROWTH FACILITY USER RESPONSIBILITIES Growth facility users must share the responsibility for quality plant care with the  

E-print Network

relationships between users and staff. Arabidopsis Growth Chamber Policy Background: Arabidopsis plants for a maximum of 4 weeks after planting. Plants must then be moved to the vegetative growth chamber to mature. 3.) Plants will remain in the vegetative growth chamber until they are ready to drop seed. For most cultivars

Pawlowski, Wojtek

420

Hydrostatic pressure and aquatic plant growth: a laboratory study  

Microsoft Academic Search

A method was tested for growing aquatic vascular plants at elevated hydrostatic pressure so that the influence of other factors\\u000a will not mask the specific plant-pressure interaction.\\u000a \\u000a Eighteen species of submersed vascular plants, belonging to twelve families and several distinct growth forms, were subjected\\u000a to series of hydrostatic pressures including those well in excess of those encountered by the species

H. M. Dale

1984-01-01

421

Promotion of plant growth by polymers of lactic acid  

Microsoft Academic Search

Polymers of L-lactic acid are shown to promote plant growth. Dry weight of duckweed (Lemna minor L.) and corn (Zea mays L) was more than doubled when plants were grown in media containing the dimer of L-lactic acid, L-lactoyllactic acid. Higher polymers were equally effective at increasing plant biomass. Monomeric lactic acid and polymers of D-lactic acid showed no biological

Alan M. Kinnersley; Taylor C. Scott; John H. Yopp; George H. Whitten

1990-01-01