Tree seed rain and seed removal, but not the seed bank, impede forest recovery in bracken (Pteridium aquilinum (L.) Kuhn)-dominated clearings in the African highlands.

PubMed

Ssali, Fredrick; Moe, Stein R; Sheil, Douglas

2018-04-01

Considerable areas dominated by bracken Pteridium aquilinum (L.) Kuhn occur worldwide and are associated with arrested forest recovery. How forest recovery is impeded in these areas remains poorly understood, especially in the African highlands. The component processes that can lead to recruitment limitation-including low seed arrival, availability and persistence-are important determinants of plant communities and offer a potential explanation for bracken persistence. We investigated key processes that can contribute to recruitment limitation in bracken-dominated clearings in the Bwindi Impenetrable National Park, Uganda. We examined if differences in seed rain (dispersal limitation), soil seed bank, or seed removal (seed viability and persistence) can, individually or in combination, explain the differences in tree regeneration found between bracken-dominated areas and the neighboring forest. These processes were assessed along ten 50-m transects crossing the forest-bracken boundary. When compared to the neighboring forest, bracken clearings had fewer seedlings (bracken 11,557 ± 5482 vs. forest 34,515 ± 6066 seedlings/ha), lower seed rain (949 ± 582 vs. 1605 ± 335 tree seeds m -2  year -1 ), comparable but sparse soil seed bank (304 ± 236 vs. 264 ± 99 viable tree seeds/m 2 ), higher seed removal (70.1% ± 2.4% vs. 40.6% ± 2.4% over a 3-day interval), and markedly higher rodent densities (25.7 ± 5.4 vs. 5.0 ± 1.6 rodents per 100 trapping sessions). Camera traps revealed that rodents were the dominant animals visiting the seeds in our seed removal study. Synthesis : Recruitment limitation contributes to both the slow recovery of forest in bracken-dominated areas, and to the composition of the tree species that occur. Low seed arrival and low persistence of unburied seeds can both explain the reduced density of seedlings found in bracken versus neighboring forest. Seed removal, likely due to rodents, in particular appears sufficient to constrain forest recovery and impacts some species more severely than others.

Ptaquiloside from bracken in stream water at base flow and during storm events.

PubMed

Clauson-Kaas, Frederik; Ramwell, Carmel; Hansen, Hans Chr B; Strobel, Bjarne W

2016-12-01

The bracken fern (Pteridium spp.) densely populates both open and woodland vegetation types around the globe. Bracken is toxic to livestock when consumed, and a group of potent illudane-type carcinogens have been identified, of which the compound ptaquiloside (PTA) is the most abundant. The highly water soluble PTA has been shown to be leachable from bracken fronds, and present in the soil and water below bracken stands. This has raised concerns over whether the compound might pose a risk to drinking water sources. We investigated PTA concentrations in a small stream draining a bracken-infested catchment at base flow and in response to storm events during a growth season, and included sampling of the bracken canopy throughfall. Streams in other bracken-dominated areas were also sampled at base flow for comparison, and a controlled pulse experiment was conducted in the field to study the in-stream dynamics of PTA. Ptaquiloside concentrations in the stream never exceeded 61 ng L -1 in the base flow samples, but peaked at 2.2 μg L -1 during the studied storm events. The mass of PTA in the stream, per storm event, was 7.5-93 mg from this catchment. A clear temporal connection was observed between rainfall and PTA concentration in the stream, with a reproducible time lag of approx. 1 h from onset of rain to elevated concentrations, and returning rather quickly (about 2 h) to base flow concentration levels. The concentration of PTA behaved similar to an inert tracer (Cl - ) in the pulse experiment over a relative short time scale (minutes-hours) reflecting no PTA sorption, and dispersion and dilution considerably lowered the observed PTA concentrations downstream. Bracken throughfall revealed a potent and lasting source of PTA during rainfall, with concentrations up to 169 μg L -1 , that did not decrease over the course of the event. In the stream, the throughfall contribution to PTA cannot be separated from a possible below-ground input from litter, rhizomes and soil. Catchment-specific factors such as the soil pH, topography, hydrology, and bracken coverage will evidently affect the level of PTA observed in the receiving stream, as well as the distance from bracken, but time since precipitation seems most important. Studying PTA loads and transport in surface streams fed by bracken-infested catchments, simply taking occasional grab samples will not capture the precipitation-linked pulses. The place and time of sampling governs the findings, and including event-based sampling is essential to provide a more complete picture of PTA loads to surface water. Copyright © 2016 Elsevier Ltd. All rights reserved.

Land management of bracken needs to account for bracken carcinogens--a case study from Britain.

PubMed

Rasmussen, Lars Holm; Donnelly, Eric; Strobel, Bjarne W; Holm, Peter E; Hansen, Hans Christian Bruun

2015-03-15

Bracken ferns are some of the most widespread ferns in the World causing immense problems for land managers, foresters and rangers. Bracken is suspected of causing cancer in Humans due to its content of the carcinogen ptaquiloside. Ingestion of bracken, or food and drinking water contaminated with ptaquiloside may be the cause. The aim of this study was to monitor the content of ptaquiloside in 20 bracken stands from Britain to obtain a better understanding of the ptaquiloside dynamics and to evaluate the environmental implications of using different cutting regimes in bracken management. The ptaquiloside content in fronds ranged between 50 and 5790 μg/g corresponding to a ptaquiloside load in the standing biomass of up to 590 mg/m(2) in mature fronds. Ptaquiloside was also found in the underground rhizome system (11-657 μg/g) and in decaying litter (0.1-5.8 μg/g). The amount of ptaquiloside present in bracken stands at any given time is difficult to predict and did not show any correlations with edaphic growth factors. The content of ptaquiloside turned out to be higher in fronds emerging after cutting compared to uncut fronds. Environmental risk assessment and bracken management must therefore be based on actual and site specific determinations of the ptaquiloside content. Care must be taken to avoid leaching from cut ferns to aquifers and other recipients and appropriate precautionary measures must be taken to protect staff from exposure to bracken dust. Copyright © 2015 Elsevier Ltd. All rights reserved.

Lignin signatures show the effects of changes in heather and bracken cover on the composition of organic matter in a moorland soil profile.

PubMed

Hetherington, S L; Anderson, J M

1998-11-01

Bracken (Pteridium aquilinum) is aggressively displacing heather (Calluna vulgaris) on many moorlands in Britain. We investigated the use of lignin derivatives to identify the distribution of soil organic matter (SOM) derived from bracken in moorland soil profiles formed under heather. Phenylpropanoids extracted from recently senesced litters, roots and SOM, using alkaline CuO oxidation, showed distinct signatures for bracken and heather, with vanillyl moieties dominating bracken litter extracts and vanillyl and syringyl dominating heather litter extracts. Ratios of vanillyl and syringyl concentrations characterised the SOM derived from heather and bracken better than the concentrations of the individual moieties. The analysis showed up to a depth of 5 cm under pure bracken cover, and at the interface between heather and bracken, the SOM was largely derived from bracken litter but below that depth SOM was apparently derived from heather. The use of these methods to identify the plant origin of SOM not only enables understanding the effects of changing vegetation cover on organic matter dynamics in moorland soils but could also facilitate management techniques in moorland/heathland restoration which involve the removal of comparatively nutrient-rich SOM derived from bracken.

Detection and mapping the spatial distribution of bracken fern weeds using the Landsat 8 OLI new generation sensor

NASA Astrophysics Data System (ADS)

Matongera, Trylee Nyasha; Mutanga, Onisimo; Dube, Timothy; Sibanda, Mbulisi

2017-05-01

Bracken fern is an invasive plant that presents serious environmental, ecological and economic problems around the world. An understanding of the spatial distribution of bracken fern weeds is therefore essential for providing appropriate management strategies at both local and regional scales. The aim of this study was to assess the utility of the freely available medium resolution Landsat 8 OLI sensor in the detection and mapping of bracken fern at the Cathedral Peak, South Africa. To achieve this objective, the results obtained from Landsat 8 OLI were compared with those derived using the costly, high spatial resolution WorldView-2 imagery. Since previous studies have already successfully mapped bracken fern using high spatial resolution WorldView-2 image, the comparison was done to investigate the magnitude of difference in accuracy between the two sensors in relation to their acquisition costs. To evaluate the performance of Landsat 8 OLI in discriminating bracken fern compared to that of Worldview-2, we tested the utility of (i) spectral bands; (ii) derived vegetation indices as well as (iii) the combination of spectral bands and vegetation indices based on discriminant analysis classification algorithm. After resampling the training and testing data and reclassifying several times (n = 100) based on the combined data sets, the overall accuracies for both Landsat 8 and WorldView-2 were tested for significant differences based on Mann-Whitney U test. The results showed that the integration of the spectral bands and derived vegetation indices yielded the best overall classification accuracy (80.08% and 87.80% for Landsat 8 OLI and WorldView-2 respectively). Additionally, the use of derived vegetation indices as a standalone data set produced the weakest overall accuracy results of 62.14% and 82.11% for both the Landsat 8 OLI and WorldView-2 images. There were significant differences {U (100) = 569.5, z = -10.8242, p < 0.01} between the classification accuracies derived based on Landsat OLI 8 and those derived using WorldView-2 sensor. Although there were significant differences between Landsat and WorldView-2 accuracies, the magnitude of variation (9%) between the two sensors was within an acceptable range. Therefore, the findings of this study demonstrated that the recently launched Landsat 8 OLI multispectral sensor provides valuable information that could aid in the long term continuous monitoring and formulation of effective bracken fern management with acceptable accuracies that are comparable to those obtained from the high resolution WorldView-2 commercial sensor.

Ptaquiloside in Irish Bracken Ferns and Receiving Waters, with Implications for Land Managers.

PubMed

O'Driscoll, Connie; Ramwell, Carmel; Harhen, Brendan; Morrison, Liam; Clauson-Kaas, Frederik; Hansen, Hans Christian B; Campbell, Graeme; Sheahan, Jerome; Misstear, Bruce; Xiao, Liwen

2016-04-26

Ptaquiloside, along with other natural phytotoxins, is receiving increased attention from scientists and land use managers. There is an urgent need to increase empirical evidence to understand the scale of phytotoxin mobilisation and potential to enter into the environment. In this study the risk of ptaquiloside to drinking water was assessed by quantifying ptaquiloside in the receiving waters at three drinking water abstraction sites across Ireland and in bracken fronds surrounding the abstraction sites. We also investigated the impact of different management regimes (spraying, cutting and rolling) on ptaquiloside concentrations at plot-scale in six locations in Northern Ireland, UK. Ptaquiloside concentrations were determined using recent advances in the use of LC-MS for the detection and quantification of ptaquiloside. The results indicate that ptaquiloside is present in bracken stands surrounding drinking water abstractions in Ireland, and ptaquiloside concentrations were also observed in the receiving waters. Furthermore, spraying was found to be the most effective bracken management regime observed in terms of reducing ptaquiloside load. Increased awareness is vital on the implications of managing land with extensive bracken stands.

Unintended consequences of invasive predator control in an Australian forest: overabundant wallabies and vegetation change.

PubMed

Dexter, Nick; Hudson, Matt; James, Stuart; Macgregor, Christopher; Lindenmayer, David B

2013-01-01

Over-abundance of native herbivores is a problem in many forests worldwide. The abundance of native macropod wallabies is extremely high at Booderee National Park (BNP) in south-eastern Australia. This has occurred because of the reduction of exotic predators through an intensive baiting program, coupled with the absence of other predators. The high density of wallabies at BNP may be inhibiting the recruitment of many plant species following fire-induced recruitment events. We experimentally examined the post-fire response of a range of plant species to browsing by wallabies in a forest heavily infested with the invasive species, bitou bush Chrysanthemoides monilifera. We recorded the abundance and size of a range of plant species in 18 unfenced (browsed) and 16 fenced (unbrowsed) plots. We found the abundance and size of bitou bush was suppressed in browsed plots compared to unbrowsed plots. Regenerating seedlings of the canopy or middle storey tree species Eucalyptus pilularis, Acacia implexa, Allocasuarina littoralis, Breynia oblongifolia and Banksia integrifolia were either smaller or fewer in number in grazed plots than treatment plots as were the vines Kennedia rubicunda, Glycine tabacina and Glycine clandestina. In contrast, the understorey fern, Pteridium esculentum increased in abundance in the browsed plots relative to unbrowsed plots probably because of reduced competition with more palatable angiosperms. Twelve months after plots were installed the community structure of the browsed and unbrowsed plots was significantly different (P = 0.023, Global R = 0.091). The relative abundance of C. monilifera and P. esculentum contributed most to the differences. We discuss the possible development of a low diversity bracken fern parkland in Booderee National Park through a trophic cascade, similar to that caused by overabundant deer in the northern hemisphere. We also discuss its implications for broad scale fox control in southern Australian forests.

Unintended Consequences of Invasive Predator Control in an Australian Forest: Overabundant Wallabies and Vegetation Change

PubMed Central

Dexter, Nick; Hudson, Matt; James, Stuart; MacGregor, Christopher; Lindenmayer, David B.

2013-01-01

Over-abundance of native herbivores is a problem in many forests worldwide. The abundance of native macropod wallabies is extremely high at Booderee National Park (BNP) in south-eastern Australia. This has occurred because of the reduction of exotic predators through an intensive baiting program, coupled with the absence of other predators. The high density of wallabies at BNP may be inhibiting the recruitment of many plant species following fire-induced recruitment events. We experimentally examined the post-fire response of a range of plant species to browsing by wallabies in a forest heavily infested with the invasive species, bitou bush Chrysanthemoides monilifera. We recorded the abundance and size of a range of plant species in 18 unfenced (browsed) and 16 fenced (unbrowsed) plots. We found the abundance and size of bitou bush was suppressed in browsed plots compared to unbrowsed plots. Regenerating seedlings of the canopy or middle storey tree species Eucalyptus pilularis, Acacia implexa, Allocasuarina littoralis, Breynia oblongifolia and Banksia integrifolia were either smaller or fewer in number in grazed plots than treatment plots as were the vines Kennedia rubicunda, Glycine tabacina and Glycine clandestina. In contrast, the understorey fern, Pteridium esculentum increased in abundance in the browsed plots relative to unbrowsed plots probably because of reduced competition with more palatable angiosperms. Twelve months after plots were installed the community structure of the browsed and unbrowsed plots was significantly different (P = 0.023, Global R = 0.091). The relative abundance of C. monilifera and P. esculentum contributed most to the differences. We discuss the possible development of a low diversity bracken fern parkland in Booderee National Park through a trophic cascade, similar to that caused by overabundant deer in the northern hemisphere. We also discuss its implications for broad scale fox control in southern Australian forests. PMID:23990879

Isolation and characterisation of 13 pterosins and pterosides from bracken (Pteridium aquilinum (L.) Kuhn) rhizome.

PubMed

Mohammad, Rizgar Hassan; Nur-E-Alam, Mohammad; Lahmann, Martina; Parveen, Ifat; Tizzard, Graham J; Coles, Simon J; Fowler, Mark; Drake, Alex F; Heyes, Derren; Thoss, Vera

2016-08-01

Systematic phytochemical investigations of the underground rhizome of Pteridium aquilinum (L.) Kuhn (Dennstaedtiaceae) afforded thirty-five pterosins and pterosides. By detailed analysis of one- and two-dimensional nuclear magnetic resonance spectroscopy, circular dichroism (CD) and high-resolution mass spectrometric data, thirteen previously undescribed pterosins and pterosides have been identified. Interestingly, for the first time 12-O-β-D-glucopyranoside substituted pterosins, rhedynosides C and D, and the sulfate-containing pterosin, rhedynosin H, alongside the two known compounds, histiopterosin A and (2S)-pteroside A2, were isolated from the rhizomes of subsp. aquilinum of bracken. In addition, six-membered cyclic ether pterosins and pterosides, rhedynosin A and rhedynoside A, are the first examples of this type of pterosin-sesquiterpenoid. Additionally, the three previously reported compounds (rhedynosin I, (2S)-2-hydroxymethylpterosin E and (2S)-12-hydroxypterosin A) were obtained for the first time from plants as opposed to mammalian metabolic products. Single crystal X-ray diffraction analysis was applied to the previously undescribed compounds (2R)-rhedynoside B, (2R)-pteroside B and (2S)-pteroside K, yielding the first crystal structures for pterosides, and three known pterosins, (2S)-pterosin A, trans-pterosin C and cis-pterosin C. Rhedynosin C is the only example of the cyclic lactone pterosins with a keto group at position C-14. Six selected pterosins ((2S)-pterosin A, (2R)-pterosin B and trans-pterosin C) and associated glycosides ((2S)-pteroside A, (2R)-pteroside B and pteroside Z) were assessed for their anti-diabetic activity using an intestinal glucose uptake assay; all were found to be inactive at 300 μM. Copyright © 2016 Elsevier Ltd. All rights reserved.

An Exploration into Fern Genome Space.

PubMed

Wolf, Paul G; Sessa, Emily B; Marchant, Daniel Blaine; Li, Fay-Wei; Rothfels, Carl J; Sigel, Erin M; Gitzendanner, Matthew A; Visger, Clayton J; Banks, Jo Ann; Soltis, Douglas E; Soltis, Pamela S; Pryer, Kathleen M; Der, Joshua P

2015-08-26

Ferns are one of the few remaining major clades of land plants for which a complete genome sequence is lacking. Knowledge of genome space in ferns will enable broad-scale comparative analyses of land plant genes and genomes, provide insights into genome evolution across green plants, and shed light on genetic and genomic features that characterize ferns, such as their high chromosome numbers and large genome sizes. As part of an initial exploration into fern genome space, we used a whole genome shotgun sequencing approach to obtain low-density coverage (∼0.4X to 2X) for six fern species from the Polypodiales (Ceratopteris, Pteridium, Polypodium, Cystopteris), Cyatheales (Plagiogyria), and Gleicheniales (Dipteris). We explore these data to characterize the proportion of the nuclear genome represented by repetitive sequences (including DNA transposons, retrotransposons, ribosomal DNA, and simple repeats) and protein-coding genes, and to extract chloroplast and mitochondrial genome sequences. Such initial sweeps of fern genomes can provide information useful for selecting a promising candidate fern species for whole genome sequencing. We also describe variation of genomic traits across our sample and highlight some differences and similarities in repeat structure between ferns and seed plants. © The Author(s) 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Revisiting an old disease? Risk factors for bovine enzootic haematuria in the Kingdom of Bhutan.

PubMed

Hidano, Arata; Sharma, Basant; Rinzin, Karma; Dahal, Narapati; Dukpa, Kinzang; Stevenson, Mark A

2017-05-01

Bovine enzootic haematuria (BEH) is a debilitating disease of cattle caused by chronic ingestion of bracken fern. Control of BEH is difficult when bracken fern is abundant and fodder resources are limited. To fill a significant knowledge gap on modifiable risk factors for BEH, we conducted a case-control study to identify cattle management practices associated with BEH in the Bhutanese cattle population. A case-control study involving 16 of the 20 districts of Bhutan was carried out between March 2012 and June 2014. In Bhutan sodium acid phosphate and hexamine (SAP&H) is used to treat BEH-affected cattle. All cattle greater than three years of age and treated with SAP&H in 2011 were identified from treatment records held by animal health offices. Households with at least one SAP&H-treated cattle were defined as probable cases. Probable case households were visited and re-classified as confirmed case households if the BEH status of cattle was confirmed following clinical examination and urinalysis. Two control households were selected from the same village as the case household. Households were eligible to be controls if: (1) householders reported that none of their cattle had shown red urine during the previous five years, and (2) haematuria was absent in a randomly selected animal from the herd following clinical examination. Details of cattle management practices were elicited from case and control householders using a questionnaire. A conditional logistic regression model was used to quantify the association between exposures of interest and household BEH status. A total of 183 cases and 345 controls were eligible for analysis. After adjusting for known confounders, the odds of free-grazing for two and three months in the spring were 3.81 (95% CI 1.27-11.7) and 2.28 (95% CI 1.15-4.53) times greater, respectively, in case households compared to controls. The odds of using fresh fern and dry fern as bedding in the warmer months were 2.05 (95% CI 1.03-4.10) and 2.08 (95% CI 0.88-4.90) times greater, respectively, in cases compared to controls. This study identified two husbandry practices that could be modified to reduce the risk of BEH in Bhutanese cattle. Avoiding the use of bracken fern as bedding is desirable, however, if fern is the only available material, it should be harvested during the colder months of the year. Improving access to alternative fodder crops will reduce the need for householders to rely on free-grazing as the main source of metabolisable energy for cattle during the spring. Copyright © 2017 Elsevier B.V. All rights reserved.

Comparison of thiaminase activity in fish using the radiometric and 4-nitrothiophenol colorimetric methods

USGS Publications Warehouse

Honeyfield, D.C.; Hanes, J.W.; Brown, L.; Kraft, C.E.; Begley, T.P.

2010-01-01

Thiaminase induced thiamine deficiency occurs in fish, humans, livestock and wild animals. A non-radioactive thiaminase assay was described in 2007, but a direct comparison with the radioactive 14C-thiamine method which has been in use for more than 30years has not been reported. The objective was to measure thiaminase activity in forage fish (alewife Alosa pseudoharengus, rainbow smelt Osmerus mordax, and slimy sculpin Cottus cognatus) consumed by predators that manifest thiamine deficiency using both methods. Modifications were made to the colorimetric assay to improve repeatability. Modification included a change in assay pH, enhanced sample clean-up, constant assay temperature (37??C), increase in the concentration of 4-nitrothiophenol (4NTP) and use of a spectrophotometer fitted with a 0.2cm cell. A strong relationship between the two assays was found for 51 alewife (R2=0.85), 36 smelt (R2=0.87) and 20 sculpin (R2=0.82). Thiaminase activity in the colorimetric assay was about 1000 times higher than activity measured by the radioactive method. Application of the assay to fish species from which no thiaminase activity has previously been reported resulted in no 4NTP thiaminase activity being found in bloater Coregonus hoyi, lake trout Salvelinus namaycusch, steelhead trout Oncorhynchus mykiss or Chinook salmon Oncorhynchus tshawytscha. In species previously reported to contain thiaminase, 4NTP thiaminase activity was measured in bacteria Paenibacillus thiaminolyticus, gizzard shad Dorosoma cepedianum, bracken fern Pteridium aquilinum, quagga mussel Dreissena bugensis and zebra mussels D. polymorpha. ?? 2010.

Supplemental treatments to aid planted Douglas-fir in dense bracken fern

Treesearch

Edward J. Dimock

1964-01-01

Why do some forest lands restock quickly and well after timber cutting but others do not? Answers have been slow in coming--partl y because of empiricism in research, partly because of the problem's general complexity, A part of the general problem concerns the poor survival of, planted Douglas-fir (Pseudotsuga menziesii var, menziesii) on...

Interference of Pteridium arachnoideum (Kaulf.) Maxon. (Dennstaedtiaceae) on the establishment of rainforest trees.

PubMed

Silva Matos, D M; Belinato, T A

2010-05-01

In order to identify the effect of P. arachnoideum, we studied 11 native tree species commonly used in reforestation projects. Bioassays were conducted in laboratory to evaluate the effect of bracken leachate on the germination and morphology of seedlings. Juveniles of some of these species were planted in two adjacent but contrasting areas in relation to the dominance of P. arachnoideum. The evaluation of growth and survivorship was performed after six and twelve months. This study reveals that for some pioneer and secondary trees P. arachnoideum leachate exerted an inhibitory effect on seed germination and seedling morphology. Field experiments revealed that pioneers are apparently more resistant to P. arachnoideum leachate than secondary species.

Ferns and fires: Experimental charring of ferns compared to wood and implications for paleobiology, paleoecology, coal petrology, and isotope geochemistry

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

McParland, L.C.; Collinson, M.E.; Scott, A.C.

We report the effects of charring on the ferns Osmunda, Pteridium, and Matteucia with coniferous wood (Sequoia) for comparison. Like charred wood, charred ferns shrink, become black and brittle with a silky sheen, and retain three-dimensional cellular structure. Ferns yield recognizable charcoal (up to 800{sup o}C) that could potentially survive in the fossil record enabling reconstruction of ancient fire-prone vegetation containing ferns. Charred fossils of herbaceous ferns would indicate surface fires. Like charred wood, cell-wall layers of charred ferns homogenize, and their reflectance values increase with rising temperature. Charcoalified fragments of thick-walled cells from conifer wood or fern tissues aremore » indistinguishable and so cannot be used to infer the nature of source vegetation. Charred conifer wood and charred fern tissues show a relationship between mean random reflectance and temperature of formation and can be used to determine minimum ancient fire temperatures. Charred fern tissues consistently have significantly more depleted {delta}{sup 13}C values ({le} 4 parts per thousand) than charred wood. Therefore, if an analysis of {delta} {sup 13}C through time included fern charcoal among a succession of wood charcoals, any related shifts in {delta} {sup 13}C could be misinterpreted as atmospheric changes or misused as isotope stratigraphic markers. Thus, charcoals of comparable botanical origin and temperatures of formation should be used in order to avoid misinterpretations of shifts in {delta}{sup 13}C values.« less

The role of Pteridium arachnoideum(Kaulf) on the seed bank of the endangered Brazilian Cerrado.

PubMed

Xavier, R O; Alday, J G; Marrs, R H; Matos, D M S

2016-02-01

The native bracken (Pteridium arachnoideum) often occurs in mono-specific stands in the Brazilian Cerrado, and this dominance can impact on both the above-ground vegetation and soil seed bank. This study investigated how invasion by this species over a 20-year period changed the seed bank and the relationship between the seed bank and litter mass. We extracted soil samples from three replicated invaded and uninvaded sites, and followed seedling emergence for six months. We collected the above-ground biomass and litter of P. arachnoideum in ten 1m2 plots from three invaded sites. There was no difference between invaded and uninvaded areas in seed bank richness, diversity or overall abundance. The most abundant family was the Melastomataceae, followed by the Poaceae. The Melastomataceae was more abundant in uninvaded sites, but the most common species of this family (Tibouchinastenocarpa) was not affected. The grasses were more common in invaded sites in the rainy season and were affected by heterogeneity in the litter layer. The seed bank could play a role in the recovery of these invaded areas, but the presence of weeds and invasive grasses could constrain their use as a management strategy.

Chemical and mineralogical conversion of Andisols following invasion by bracken fern

Treesearch

J. L. Johnson-Maynard; P. A. McDaniel; D. E. Ferguson; A. L. Falen

1997-01-01

Andisols support ≈ 200 000 ha of mid-elevation grand fir (Abies grandis [Dougl. ex D.Don] Lindl.) forests in the Pacific Northwest region that are characterized by little or no natural conifer regeneration following removal of the forest canopy. Previous work suggests that the properties of these Andisols have been altered as a result of the establishment of...

Chemical Constituents Analysis and Antidiabetic Activity Validation of Four Fern Species from Taiwan

PubMed Central

Chen, Chen-Yu; Chiu, Fu-Yu; Lin, Yenshou; Huang, Wei-Jan; Hsieh, Po-Shiuan; Hsu, Feng-Lin

2015-01-01

Pterosins are abundant in ferns, and pterosin A was considered a novel activator of adenosine monophosphate-activated protein kinase, which is crucial for regulating blood glucose homeostasis. However, the distribution of pterosins in different species of ferns from various places in Taiwan is currently unclear. To address this question, the distribution of pterosins, glucose-uptake efficiency, and protective effects of pterosin A on β-cells were examined. Our results showed that three novel compounds, 13-chloro-spelosin 3-O-β-d-glucopyranoside (1), (3R)-Pterosin D 3-O-β-d-(3'-p-coumaroyl)-glucopyranoside (2), and (2R,3R)-Pterosin L 3-O-β-d-(3'-p-coumaroyl)-glucopyranoside (3), were isolated for the first time from four fern species (Ceratopteris thalictroides, Hypolepis punctata, Nephrolepis multiflora, and Pteridium revolutum) along with 27 known compounds. We also examined the distribution of these pterosin compounds in the mentioned fern species (except N. multiflora). Although all pterosin analogs exhibited the same effects in glucose uptake assays, pterosin A prevented cell death and reduced reactive oxygen species (ROS) production. This paper is the first report to provide new insights into the distribution of pterosins in ferns from Taiwan. The potential anti-diabetic activity of these novel phytocompounds warrants further functional studies. PMID:25622260

Control of Pteridium aquilinum: Meta-analysis of a Multi-site Study in the UK

PubMed Central

Stewart, Gavin; Cox, Emma; Le Duc, Mike; Pakeman, Robin; Pullin, Andrew; Marrs, Rob

2008-01-01

Background and Aims A great deal of money is spent controlling invasive weeds as part of international and national policies. It is essential that the funded treatments work across the region in which the policies operate. We argue that experiments across multiple sites are required to validate these programs as results from single sites may be misleading. Here, the control of Pteridium aquilinum (bracken) is used as a test example to address the following four questions. (1) Does the effectiveness of P. aquilinum-control treatments vary across sites? (2) Is the best treatment identified in previous research (cutting twice per year) consistent at all sites, and if not why not? (3) Is treatment performance related to P. aquilinum rhizome mass, litter cover or litter depth at the various sites? (4) Does successful P. aquilinum control influence species richness? Methods Pteridium aquilinum‐control treatments were monitored for 10 years using six replicated experiments and analysed using meta-analysis. Meta-regressions were used to explore heterogeneity between sites. Key Results The effectiveness of treatments varied between sites depending on the measure used to assess P. aquilinum performance. In general, cutting twice per year was the most successful treatment but on some sites other, less expensive treatments were as good. The effectiveness of treatments at different sites was not related to rhizome mass, but the effectiveness of most applied treatments were inversely related to post-control litter. Effective treatment was also associated with high species richness. Conclusions It is concluded that successful development of national weed control programs requires multi-site experimental approaches. Here, meta-analyses demonstrate that variation in effectiveness between sites could be explained in part by pre-specified variables. Reliance on data from a single site for policy formulation is therefore clearly dangerous. PMID:18337356

Remedial Investigations Report for Fort Devens Subbury Training Annex, Maynard, Massachusetts, Sites P11/P13 and Sites A12/P36/P37, Phase 2. Volume 1

DTIC Science & Technology

1995-12-01

woody vines occur in this area. Scarboro muck, the underlying soil in this wetland area, is listed by the SCS as a hydric soil (USDA 1987). Hydric...dense understory consists primarily of regenerating overstory and flowering dogwood. In addition, woody vines , including poison ivy, Virginia Creeper, and...covers the ground. Mosses, partridge berry, bracken fern, and pink ladyslipper comprise the sparsely vegetated herbaceous layer. No woody vines grow in

Degradation kinetics of ptaquiloside in soil and soil solution.

PubMed

Ovesen, Rikke Gleerup; Rasmussen, Lars Holm; Hansen, Hans Christian Bruun

2008-02-01

Ptaquiloside (PTA) is a carcinogenic norsesquiterpene glycoside produced in bracken (Pteridium aquilinum (L.) Kuhn), a widespread, aggressive weed. Transfer of PTA to soil and soil solution eventually may contaminate groundwater and surface water. Degradation rates of PTA were quantified in soil and soil solutions in sandy and clayey soils subjected to high natural PTA loads from bracken stands. Degradation kinetics in moist soil could be fitted with the sum of a fast and a slow first-order reaction; the fast reaction contributed 20 to 50% of the total degradation of PTA. The fast reaction was similar in all horizons, with the rate constant k(1F) ranging between 0.23 and 1.5/h. The slow degradation, with the rate constant k(1S) ranging between 0.00067 and 0.029/ h, was more than twice as fast in topsoils compared to subsoils, which is attributable to higher microbial activity in topsoils. Experiments with sterile controls confirmed that nonmicrobial degradation processes constituted more than 90% of the fast degradation and 50% of the slow degradation. The lower nonmicrobial degradation rate observed in the clayey compared with the sandy soil is attributed to a stabilizing effect of PTA by clay silicates. Ptaquiloside appeared to be stable in all soil solutions, in which no degradation was observed within a period of 28 d, in strong contrast to previous studies of hydrolysis rates in artificial aqueous electrolytes. The present study predicts that the risk of PTA leaching is controlled mainly by the residence time of pore water in soil, soil microbial activity, and content of organic matter and clay silicates.

Evaluation of the anti-inflammatory and antioxidative potential of four fern species from China intended for use as food supplements.

PubMed

Dion, Carine; Haug, Christian; Guan, Haifeng; Ripoll, Christophe; Spiteller, Peter; Coussaert, Aurelie; Boulet, Elodie; Schmidt, Daniel; Wei, Jianbing; Zhou, Yijun; Lamottke, Kai

2015-04-01

Inflammation plays a major role in many diseases, for instance in arteriosclerosis, rheumatoid arthritis, autoimmune disorders and cancer. Since many plants contain compounds with anti-inflammatory activity, their consumption may be able to prevent the development of inflammatory-based diseases. Edible ferns are some of the most important wild vegetables in China and have traditionally been used both for dietary and therapeutic purposes. In this study we investigated the anti-inflammatory and antioxidant potential of fern extracts from Matteuccia struthiopteris, Osmundajaponica, Matteuccia orientalis and Pteridium aquilinum intended for use as nutraceuticals. Two modes of action were investigated: the inhibition of the pro-inflammatory gene expression of interleukin-1 beta (IL1-β) and interleukin-6 (IL6), and the gene expression of iNOS by LPS-elicited macrophages. The results showed a decrease of IL1-β gene expression for the five fern extracts. This effect was more pronounced for the extracts prepared from the roots of O. japonica (IC50 of 17.8 µg/mL) and the young fronds of M orientalis (50.0 µg/mL). Regarding the indirect measurement of NO, via iNOS gene expression, an interesting decrease of 50% was obtained with the extract of M. orientalis fronds at a low concentration (20 µg/mL) compared with P. aquilinum fronds (160 µg/mL) and leaves of O. japonica. The latter showed a higher decrease but at a high concentration of extract (160 µg/mL). The five fern extracts were also evaluated for their ability to scavenge 2,2-diphenyl-l-picrylhydrazyl (DPPH) radicals and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS). All fern extracts exhibited antioxidant effects but the roots of O. japonica and the fronds of M orientalis were most efficient. The HPLC-MS analysis of the constituents of the fern extracts confirmed the presence of chlorogenic acid, caffeic acid, p-coumaric acid, ferulic acid, kaempferol and apigenin, molecules known to exhibit antiinflammatory and/or antioxidant properties.

Description of a new genus and two new species of high frequency cicada from New Caledonia (Insecta: Hemiptera, Cicadoidea, Cicadidae).

PubMed

Delorme, Quentin; Mille, Christian; Jourdan, Hervé

2016-06-21

The new genus Murmurillana Delorme gen. nov., is described within the tribe Cicadettini Buckton, 1889, designating Murmurillana inaudibilis Delorme sp. nov., as the type species. Murmurillana inaudibilis Delorme sp. nov. and Murmurillana paenetacita Delorme sp. nov. are described from New Caledonia. They are respectively found in mid altitude dense Niaouli shrub (Melaleuca quinquenervia, Myrtaceae) vegetation, mixed with dense fern cover (Pteridium sp., Dennstaedtiaceae) on the Massif of Aoupinié (800 m) and on foothills of the Mont Panié (570 m). Male calling songs of the two new species are described from field recordings. These calling songs exhibit unusually high dominant frequencies. A key to the species of Murmurillana Delorme gen. nov., is also provided.

Pollen core assemblages as indicator of Polynesian and European impact on the vegetation cover of Auckland Isthmus catchment, New Zealand

NASA Astrophysics Data System (ADS)

Abrahim, Ghada M. S.; Parker, Robin J.; Horrocks, Mark

2013-10-01

Tamaki Estuary is an arm of the Hauraki Gulf situated on the eastern side of central Auckland. Over the last 100 years, Tamaki catchment has evolved from a nearly rural landscape to an urbanised and industrialised area. Pollen, 14C and glass shards analyses, were carried out on three cores collected along the estuary with the aim to reconstruct the estuary's history over the last ˜8000 years and trace natural and anthropogenic effects recorded in the sediments. Glass shard analysis was used to establish key tephra time markers such as the peralkaline eruption of Mayor Island, ˜6000 years BP. During the pre-Polynesian period (since at least 8000 years BP), regional vegetation was podocarp/hardwood forest dominated by Dacrydium cupressinun, Prumnopits taxifolia, and Metrosideros. Major Polynesian settler impact (commencing ˜700 yr BP) was associated with forest clearance as indicated by a sharp decline in forest pollen types. This coincided with an increase in bracken (Pteridium esculentum) spores and grass pollen. Continuing landscape disturbance during European settlement (commencing after 1840 AD) was accompanied by the distinctive appearance of exotic pollen taxa such as Pinus.

Response of soil microbial activity and community structure to land use changes in a mountain rainforest region of Southern Ecuador

NASA Astrophysics Data System (ADS)

Potthast, Karin; Hamer, Ute; Makeschin, Franz

2010-05-01

Over the past several decades the mountain rainforest region of Southern Ecuador, a hotspot of biodiversity, is undergoing a rapid conversion to pastureland through slash and burn practice. Frequently this pastureland is invaded by the tropical bracken fern. When the bracken becomes dominant on the pasture sites the productivity decreases and the sites are abandoned. To assess the effect of these land use changes on nutrient turnover and on ecosystem functioning, a study was conducted in the area of the German research station Estación Científica San Francisco (ECSF) in Southern Ecuador. At 2000 m above sea level three adjacent sites were selected: a mountain rainforest site, an active pasture site dominated by the grass species Setaria sphacelata and an abandoned pasture site overgrown by bracken. Mineral soil samples of all three sites (0-5, 5-10 and 10-20 cm) as well as samples from the organic layer (Oi and Oa) of the natural forest site were taken to analyze biogeochemical properties. Besides pH-value, total organic C and N contents, the amounts of microbial biomass (CFE-method), microbial activity (basal respiration, net N mineralization (KCl-extraction); gross N mineralization (15N dilution technique) rates) and microbial community structure (PLFA-analysis) were determined. 17 years after pasture establishment, twofold higher stocks of soil microbial biomass carbon (Cmic) and nitrogen (Nmic) as well as significant lower C:N ratios were determined compared to the natural forest including the 11 cm thick organic layer. 10 years after bracken invasion and pasture abandonment the microbial biomass (Cmic) decreased and the C:N ratio increased again to forest levels. Generally, land use change from forest to pasture and from pasture to abandoned pasture induced shifts in the soil microbial community structure. The relative abundance of the fast growing copiotrophic Gram(-) bacteria was positively correlated with the amounts of readily available organic carbon (DOC_KCl) and nitrogen (TDN_KCl). Thereby, the highest amounts of DOC_KCl and TDN_KCl were associated with high carbon and nitrogen mineralization rates which resulted from the supply of fresh organic substrate from the litter in the forest as well as from easily degradable organic substrate from root exudates of the dense fine-root system of the Setaria grass. Comparing 0 to 5 cm depth, the active pasture showed the highest carbon mineralization, gross N mineralization and ammonium consumption rates which corresponded to the lowest net N mineralization rates indicating an active microbial immobilization of inorganic N. Furthermore, this was associated with the lowest Cmic:Nmic ratio compared to the other land uses. The metabolic quotient of 0 to 5 cm depth increased from 1.1 (forest) to 1.8 (pasture) to 2.7 mg CO2-C g-1 Cmic h-1 (abandoned pasture) indicating the lowest substrate use efficiency after the invasion of bracken due to a higher C:N ratio and lignin content of the bracken residues (Potthast et al., 2010). Mineralization rates of all three land use types were affected by the amount of organic matter susceptible to decomposition. Thereby, the land use change from an active to an abandoned pasture showed an impact on nutrient transfer and on the amount of soil N supplied to plants. Potthast, K., Hamer, U., Makeschin, F., 2010. Impact of litter quality on mineralization processes in managed and abandoned pasture soils in Southern Ecuador. Soil Biology and Biochemistry 42, 56-64.

Fern-synthesized nanoparticles in the fight against malaria: LC/MS analysis of Pteridium aquilinum leaf extract and biosynthesis of silver nanoparticles with high mosquitocidal and antiplasmodial activity.

PubMed

Panneerselvam, Chellasamy; Murugan, Kadarkarai; Roni, Mathath; Aziz, Al Thabiani; Suresh, Udaiyan; Rajaganesh, Rajapandian; Madhiyazhagan, Pari; Subramaniam, Jayapal; Dinesh, Devakumar; Nicoletti, Marcello; Higuchi, Akon; Alarfaj, Abdullah A; Munusamy, Murugan A; Kumar, Suresh; Desneux, Nicolas; Benelli, Giovanni

2016-03-01

Malaria remains a major public health problem due to the emergence and spread of Plasmodium falciparum strains resistant to chloroquine. There is an urgent need to investigate new and effective sources of antimalarial drugs. This research proposed a novel method of fern-mediated synthesis of silver nanoparticles (AgNP) using a cheap plant extract of Pteridium aquilinum, acting as a reducing and capping agent. AgNP were characterized by UV-vis spectrophotometry, Fourier transform infrared (FTIR) spectroscopy, energy-dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD). Phytochemical analysis of P. aquilinum leaf extract revealed the presence of phenols, alkaloids, tannins, flavonoids, proteins, carbohydrates, saponins, glycosides, steroids, and triterpenoids. LC/MS analysis identified at least 19 compounds, namely pterosin, hydroquinone, hydroxy-acetophenone, hydroxy-cinnamic acid, 5, 7-dihydroxy-4-methyl coumarin, trans-cinnamic acid, apiole, quercetin 3-glucoside, hydroxy-L-proline, hypaphorine, khellol glucoside, umbelliferose, violaxanthin, ergotamine tartrate, palmatine chloride, deacylgymnemic acid, methyl laurate, and palmitoyl acetate. In DPPH scavenging assays, the IC50 value of the P. aquilinum leaf extract was 10.04 μg/ml, while IC50 of BHT and rutin were 7.93 and 6.35 μg/ml. In mosquitocidal assays, LC50 of P. aquilinum leaf extract against Anopheles stephensi larvae and pupae were 220.44 ppm (larva I), 254.12 ppm (II), 302.32 ppm (III), 395.12 ppm (IV), and 502.20 ppm (pupa). LC50 of P. aquilinum-synthesized AgNP were 7.48 ppm (I), 10.68 ppm (II), 13.77 ppm (III), 18.45 ppm (IV), and 31.51 ppm (pupa). In the field, the application of P. aquilinum extract and AgNP (10 × LC50) led to 100 % larval reduction after 72 h. Both the P. aquilinum extract and AgNP reduced longevity and fecundity of An. stephensi adults. Smoke toxicity experiments conducted against An. stephensi adults showed that P. aquilinum leaf-, stem-, and root-based coils evoked mortality rates comparable to the permethrin-based positive control (57, 50, 41, and 49 %, respectively). Furthermore, the antiplasmodial activity of P. aquilinum leaf extract and green-synthesized AgNP was evaluated against CQ-resistant (CQ-r) and CQ-sensitive (CQ-s) strains of P. falciparum. IC50 of P. aquilinum were 62.04 μg/ml (CQ-s) and 71.16 μg/ml (CQ-r); P. aquilinum-synthesized AgNP achieved IC50 of 78.12 μg/ml (CQ-s) and 88.34 μg/ml (CQ-r). Overall, our results highlighted that fern-synthesized AgNP could be candidated as a new tool against chloroquine-resistant P. falciparum and different developmental instars of its primary vector An. stephensi. Further research on nanosynthesis routed by the LC/MS-identified constituents is ongoing.

Expanding the biomass resource: sustainable oil production via fast pyrolysis of low input high diversity biomass and the potential integration of thermochemical and biological conversion routes.

PubMed

Corton, J; Donnison, I S; Patel, M; Bühle, L; Hodgson, E; Wachendorf, M; Bridgwater, A; Allison, G; Fraser, M D

2016-09-01

Waste biomass is generated during the conservation management of semi-natural habitats, and represents an unused resource and potential bioenergy feedstock that does not compete with food production. Thermogravimetric analysis was used to characterise a representative range of biomass generated during conservation management in Wales. Of the biomass types assessed, those dominated by rush ( Juncus effuses ) and bracken ( Pteridium aquilinum ) exhibited the highest and lowest volatile compositions respectively and were selected for bench scale conversion via fast pyrolysis. Each biomass type was ensiled and a sub-sample of silage was washed and pressed. Demineralization of conservation biomass through washing and pressing was associated with higher oil yields following fast pyrolysis. The oil yields were within the published range established for the dedicated energy crops miscanthus and willow. In order to examine the potential a multiple output energy system was developed with gross power production estimates following valorisation of the press fluid, char and oil. If used in multi fuel industrial burners the char and oil alone would displace 3.9 × 10 5  tonnes per year of No. 2 light oil using Welsh biomass from conservation management. Bioenergy and product development using these feedstocks could simultaneously support biodiversity management and displace fossil fuels, thereby reducing GHG emissions. Gross power generation predictions show good potential.

Late Pleistocene and Holocene vegetation and climate changes in the Lake Baikal region

NASA Astrophysics Data System (ADS)

Demske, D.; Heumann, G.; Granoszewski, W.; Mamakowa, K.; Piotrowska, N.; Bluszcz, A.; Goslar, T.

2003-04-01

Palynological high-resolution records from Lake Baikal sediments document strong vegetational changes during the transitions from an open landscape to Late Glacial shrublands and Holocene forests. For three core sites, investigated within EU-Project CONTINENT, sporomorph concentrates were used for AMS 14C dating of environmental changes. The pollen record from the northern lake site, located in vicinity to the Barguzin Mountains, shows pronounced maxima of Salix and Picea corresponding to late Pleistocene warming. A peak maximum in Alnus fruticosa during the Younger Dryas cooling coincided with low abundance of green algae in the lake and a decline in Picea trees. Fern-rich forests with Picea, Larix and Betula developed during early Holocene. With an abrupt expansion of Pteridium ferns Abies appeared in the northeastern Baikal region, reflecting optimum conditions for dark taiga. Among pines Pinus sibirica prevailed prior to the spread of P. sylvestris. Expansion of pines points to a distinct decrease in precipitation. A palynological sequence from the same site reflects the vegetation development during the last interglacial, with differences indicated by higher abundance of Abies. The upper part of the interglacial record comprises the transition to stadial conditions. Further pollen spectra are probably equivalent to first interstadials of the early glacial period (Zyryansk). Comparison with southern sites, in vicinity to the Selenga Delta and the Khamar-Daban Mountains, reveals that regional and temporal differentiation of Holocene vegetation development and climate conditions was closely related to the distribution of mountain ranges.

Expression of gap junction protein connexin 43 in bovine urinary bladder tumours.

PubMed

Corteggio, A; Florio, J; Roperto, F; Borzacchiello, G

2011-01-01

The aetiopathogenesis of urinary bladder tumours in cattle involves prolonged ingestion of bracken fern and infection by bovine papillomavirus types 1 or 2 (BPV-1/2). The oncogenic activity of BPV is largely associated with the major oncoprotein E5. Gap junctions are the only communicating junctions found in animal tissues and are composed of proteins known as connexins. Alterations in connexin expression have been associated with oncogenesis. The present study investigated biochemically and immunohistochemically the expression of connexin 43 in samples of normal (n=2), dysplastic (n=3) and neoplastic (n=23) bovine urothelium. The tumours included 10 carcinomas in situ, five papillary urothelial carcinomas and eight invasive urothelial carcinomas. Normal and dysplastic urothelium had membrane expression of connexin 43, but this was reduced in samples of carcinoma in situ. Papillary urothelial carcinomas showed moderate cytoplasmic and membrane labelling, while invasive carcinoma showed loss of connexin 43 expression. Copyright © 2010 Elsevier Ltd. All rights reserved.

The use of sustainable 'biochar compost' for remediation of contaminated land

NASA Astrophysics Data System (ADS)

Ryan, Aoife; Street-Perrott, Alayne; Eastwood, Daniel; Brackenbury, Sion

2014-05-01

South Wales (UK) has a long industrial history which, since the collapse of the coal-mining industry, has left a large number of contaminated former colliery sites. Bio-remediation of these areas by re-vegetation with native grasses aims to prevent erosion and leaching of pollutants into drainage waters. However, acid pH, low organic-matter content and unsuitable soil structure have limited the success of re-vegetation and prompted research into the development of artificial soils. This study aims to assess the value of creating an artificial soil cover by adding "biochar compost" to the top 10cm of a large volume of contaminated colliery spoil (high in As and Cu) to be moved during construction of a flood-alleviation barrage in Cwm Dulais (Swansea). It is proposed to use biochar, manufactured from chipped biomass sourced from a local stand of invasive Rhododendron ponticum using a BiGchar 1000 fast pyrolysis-gasification unit, in combination with locally produced BSI PAS100-certified Pteridium aquilinum (bracken) compost, to remediate a large area (2.3ha) of landscaped colliery waste and re-establish a cover of native grasses suitable for sheep grazing. Pot and field trials are being used to determine the most appropriate biochar:compost mix. In a 90-day outdoor pot trial, a commercial acid-grassland seed mix was grown in screened (< 20mm) colliery spoil, to which 25%v/v bracken compost (with/without composted manure) was added as a source of organic matter. This application rate of compost (equivalent to 250m3ha-1) was based on a successful coal-tip remediation trial at Ffos-y-Frân (Jarvis & Walton, WRAP Report, 2011). Varying application rates of biochar (0%, 2%, 5%, 10% or 20%v/v) were employed. Additional benefits of adding mycorrhizal inoculant or Trifolium repens (white clover) seed were also tested. Six-fold replication was used, with appropriate controls. The performance of each treatment was assessed from its maximum sward height and final above-ground dry phytomass. To evaluate the quality of the resulting grassland for sheep grazing, grass samples are being analysed for nutrients, heavy metals and metalloids by elemental analysis (EA) and X-ray fluorescence spectroscopy (XRF). These results will be compared with grass samples collected from Cwm Dulais. Initial findings suggest that addition of biochar compost improved grass growth compared with unamended colliery spoil.

Biochar as a biosecurity tool for the management of invasive and/or infected plants.

NASA Astrophysics Data System (ADS)

Harries, Philip J. E.; Fielding, J. James; Alayne Street-Perrott, F.; Doerr, Stefan H.; Brackenbury, Sion

2014-05-01

Control of invasive alien/native plants and diseased trees is often achieved using labour-intensive mechanical methods, incurring high costs and significant carbon debt. Disposal of cleared biomass may be heavily regulated. The commonly used method, burning, wastes a potentially valuable resource. Biochar may offer a safe, cost-effective solution to the problem of disposal. Large areas of Wales are covered by bracken (Pteridium aquilinum) (37x103 ha) or invasive Rhododendron ponticum (area not yet quantified). Clearance of these plants is often necessary for agriculture or maintenance of biodiversity (bracken), or to curb the rapid dispersal of the fungus-like pathogen Phytophthora ramorum from rhododendron (the principal host) into commercial timber stands, notably Japanese larch (Larix kaempferi). In addition, ash dieback (the fungal disease Hymenoscyphus pseudoalbidus aka Chalara fraxinea) is now spreading aggressively in common ash trees (Fraxinus excelsior) in the UK. Pilot-scale experiments are being conducted using a BiGchar 1000 mobile, fast pyrolysis -gasification unit, focussing on chipped rhododendron, Japanese larch and common ash feedstocks. Preliminary results of these experiments will be presented. The biochars produced are being subjected to a range of physical and chemical analyses. Levels of micro- and macro-nutrients retained from the original feedstocks are being evaluated. Organic and inorganic contaminants are also being compared with those in the respective feedstocks. Biochar produced from R. ponticum comprised C 63.7-85.9%, H 0.4-0.8%, N 0.4-0.8%, S 0.27-1.79% and O 4.1-27.4%, with most of the mineral nutrients being retained from the original feedstock, especially Mn. Larch biochar comprised C 84.1-91.7%, H 1.8-3.1%, N 0.3-0.8%, S 0.42-0.69% and O 4.1-10.7%. Heavy-metal concentrations were below recommended limits (International Biochar Initiative, 2012), although R. ponticum growing on highly acidified soils showed some tendency to bio-accumulate Fe, Al and Cu. Life-Cycle Analyses of the pyrolysis unit and production process will be used to estimate the amount of carbon offset achievable during the operational lifetime of the unit. In addition, both gaseous and particulate emissions are being monitored in order to determine the environmental impact of the production process and ensure compliance with emissions regulations.

Gastric cancer in Gwynedd. Possible links with bracken.

PubMed Central

Galpin, O. P.; Whitaker, C. J.; Whitaker, R.; Kassab, J. Y.

1990-01-01

One hundred and one histologically confirmed gastric cancer patients in Gwynedd, North Wales, were matched by sex, age and social class to two hospital inpatients without cancer. Seventy-seven of the gastric cancer cases were also matched, using the same criteria, to a patient with a confirmed cancer of a different site (excluding oesophagus). A questionnaire was used to determine bracken exposure and source of water in childhood. Residential and occupational histories were obtained and the consumption of buttermilk, a potential vector of the bracken carcinogens, was quantified. Comparison of the gastric cancer patients with the non-cancer controls indicated that exposure to bracken in childhood had an increased risk (RR = 2.34, P less than 0.001) compared to no exposure and that length of residence in Gwynedd was associated with increased risk (RR = 2.46 for durations of 61 years and over, P less than 0.01). Consumption of buttermilk in childhood and adulthood was attended by increased risk (RR = 1.61 and 1.86 respectively, the latter being statistically significant, P less than 0.05). Neither the residence effect nor consumption of buttermilk in adulthood remained significant when considered in a multivariate analysis with bracken exposure. PMID:2337510

Spanish Translation and Validation of the Bracken Basic Concept Scale.

ERIC Educational Resources Information Center

Bracken, Bruce A; Fouad, Nadya

1987-01-01

The Bracken Basic Concept Scale (BBCS) was translated into Spanish, and 32 preschool and primary age bilingual children were assessed in a counter-balanced format with the English and newly translated Spanish forms to assess the adequacy of the translation. Preliminary content validity of the Spanish BBCS was demonstrated. (Author/JAZ)

Multinational Validation of the Spanish Bracken Basic Concept Scale for Cross-Cultural Assessments.

ERIC Educational Resources Information Center

Bracken, Bruce A.; And Others

1990-01-01

Investigated construct validity of the Spanish translation of the Bracken Basic Concept Scale (BBCS) in Latino children (n=293) including monolingual Spanish-speaking children from Puerto Rico and Venezuela and Spanish-dominant bilingual Latino children from Texas. Results provided support for construct validity of the Spanish version of the…

Validity of the Bracken School Readiness Assessment for Predicting First Grade Readiness

ERIC Educational Resources Information Center

Panter, Janet E.; Bracken, Bruce A.

2009-01-01

The Bracken School Readiness Assessment (BSRA) was administered to all kindergarten students enrolled in two rural elementary schools in the fall of 2004. Eight months later, the reading portion of the Metropolitan Readiness Tests, 6th Edition (MRT-6) was administered. Teachers were asked to indicate whether they had concerns about each student's…

Reliability of Bracken School Readiness Assessment, Third Edition Scores with Young Children in Mumbai, India

ERIC Educational Resources Information Center

Shah, Mira B.; Schaefer, Barbara A.; Clark, Teresa P.

2013-01-01

To effectively provide early interventions to children, identifying those who are in need of these interventions is essential. In India, several problems hinder the process of early identification, including a lack of standardized measures for assessment. This study investigates the utility of the Bracken School Readiness Assessment, Third Edition…

Construct Validity Evidence for Bracken School Readiness Assessment, Third Edition, Spanish Form Scores

ERIC Educational Resources Information Center

Ortiz, Arlene; Clinton, Amanda; Schaefer, Barbara A.

2015-01-01

Convergent and discriminant validity evidence was examined for scores on the Spanish Record Form of the Bracken School Readiness Assessment, Third Edition (BSRA-3). Participants included a sample of 68 Hispanic, Spanish-speaking children ages 4 to 5 years enrolled in preschool programs in Puerto Rico. Scores obtained from the BSRA-3 Spanish Record…

Disturbance gradient shows logging affects plant functional groups more than fire.

PubMed

Blair, David P; McBurney, Lachlan M; Blanchard, Wade; Banks, Sam C; Lindenmayer, David B

2016-10-01

Understanding the impacts of natural and human disturbances on forest biota is critical for improving forest management. Many studies have examined the separate impacts on fauna and flora of wildfire, conventional logging, and salvage logging, but empirical comparisons across a broad gradient of simultaneous disturbances are lacking. We quantified species richness and frequency of occurrence of vascular plants, and functional group responses, across a gradient of disturbances that occurred concurrently in 2009 in the mountain ash forests of southeastern Australia. Our study encompassed replicated sites in undisturbed forest (~70 yr post fire), forest burned at low severity, forest burned at high severity, unburned forest that was clearcut logged, and forest burned at high severity that was clearcut salvage logged post-fire. All sites were sampled 2 and 3 yr post fire. Mean species richness decreased across the disturbance gradient from 30.1 species/site on low-severity burned sites and 28.9 species/site on high-severity burned sites, to 25.1 species/site on clearcut sites and 21.7 species/site on salvage logged sites. Low-severity burned sites were significantly more species-rich than clearcut sites and salvage logged sites; high-severity burned sites supported greater species richness than salvage logged sites. Specific traits influenced species' sensitivity to disturbance. Resprouting species dominated undisturbed mountain ash forests, but declined significantly across the gradient. Fern and midstory trees decreased significantly in frequency of occurrence across the gradient. Ferns (excluding bracken) decreased from 34% of plants in undisturbed forest to 3% on salvage logged sites. High-severity burned sites supported a greater frequency of occurrence and species richness of midstory trees compared to clearcut and salvage logged sites. Salvage logging supported fewer midstory trees than any other disturbance category, and were distinctly different from clearcut sites. Plant life form groups, including midstory trees, shrubs, and ferns, were dominated by very few species on logged sites. The differences in biotic response across the gradient of natural and human disturbances have significant management implications, particularly the need to reduce mechanical disturbance overall and to leave specific areas with no mechanical disturbance across the cut area during logging operations, to ensure the persistence of resprouting taxa. © 2016 by the Ecological Society of America.

Exploration of the diversity and associated health benefits of traditional pickles from the Himalayan and adjacent hilly regions of Indian subcontinent.

PubMed

Chakraborty, Rakhi; Roy, Swarnendu

2018-05-01

The Himalayas have provided shelter to the various communities for thousands of years and have remained the cradle for the origin of diverse cultures and traditions. The Himalayan belt is rich in biodiversity and have ushered mankind with numerous gifts for survival and existence. The art of pickling is believed to have developed independently among the different communities of this region. In this region, the main meal is supplemented with pickles or achar that not only adds flavour, but also enhances the value of the meal and often comes with inherent health benefits. The prime objective of this article was to enlist the diverse pickles that are being prepared and consumed by the different tribes and communities, and at the same time analyse the science behind pickle preparation and health benefits and concerns associated with pickles. We have enlisted about hundred monotypic pickles, that are prepared from single fruit or vegetable; but sometimes fungi such as Agaricus and ferns like Diplazium and Pteridium have also been used. Also, fish and meat pickles are common mostly in the Eastern Himalayan region. Traditional pickles constitute the medicinal values of the ingredients and other beneficial properties conferred by the associated microorganisms.

Organochlorine insecticide residues in the free-tailed bat (Tadarida brasiliensis) at Bracken Cave, Texas

USGS Publications Warehouse

Clark, D.R.; Martin, C.O.; Swineford, D.M.

1975-01-01

Fifty-nine free-tailed bats (Tadarida brasiliensis mexicana ) were collected at Bracken Cave, Texas, and analyzed for organochlorine insecticides and polychlorinated biphenyls (PCBs). Residues of DDE in the brain were greater in 12 young collected from the floor than in 15 young taken from the ceiling, but food deprivation, not higher residues in the brain, apparently caused young to fall....Among 18 pregnant females, residues of DDE and DDT were highest in yearlings. The first lactation by yearlings caused their residue loads to drop sharply. Thereafter, increasing age was accompanied by increasing residues but amounts generally did not exceed those in yearlings.....Residue levels in embryos were a function both of levels in the female parent and degree of embryonic development. Residues accumulated rapidly in nursing young, and lactating females may excrete from 1.3 to 16.2 (mean = 4.3) micrograms of DDE in milk per day. Maximum individual residue loads may be attained toward the end of nursing, and mobilization of these residues during southward migration may subject Bracken Cave free-tails to maximum lifetime residues in the brain....Comparison of our data with residue data for the free-tail population at Eagle Creek Cave (Arizona) in 1970 produced the following conclusions: ( 1) residues of DDE appeared similar in pregnant females, embryos, lactating females, and fallen young for the two populations; (2) residues of DDT and dieldrin appeared greater in pregnant females at Bracken Cave; (3) DDE and DDT occurred at greater levels in guano samples from Bracken Cave. On this basis, the population decline observed at Eagle Creek Cave between 1963 and 1969 does not appear to be related to the residues observed in the 1970 samples taken from that cave.

Bovine papillomavirus type 2 infection and a series of mesenchymal tumors of the urinary bladder in cattle.

PubMed

Martano, Manuela; Roperto, Franco; Stocco, Rita de Cassia; Russo, Valeria; Borzacchiello, Giuseppe; Paciello, Orlando; Iovane, Valentina; Leonardi, Leonardo; Maiolino, Paola; Restucci, Brunella; Papparella, Serenella; Roperto, Sante

2013-01-01

This report describes the histopathology of two hundred and fifty-three mesenchymal tumors of the urinary bladder in cattle grazing on lands rich in bracken fern. Approximately 80% were hemangiomas and angiosarcomas. Hemangioma (capillary, cavernous, and large vessels) was the most frequent mesenchymal tumor and was more common than angiosarcoma. Although the appearance of endothelial cells can vary remarkably, epithelioid angiosarcomas, often containing multinucleated cells, were the most frequent malignant vascular tumors. Hemangiopericytoma and tumors of muscle and soft connective tissue origin, alone and/or in association with tumor-like lesions, were less frequently seen. Furthermore, forty-five cases of intravascular papillary endothelial hyperplasia (IPEH), a lesion not previously reported in the urinary bladder of cattle, were also described. Bovine papillomavirus type-2 DNA was amplified in tumor samples. Forty vascular tumors were investigated by dual-labeling immunofluorescence, and, for the first time, a coexpression of E5 and platelet-derived growth factor β receptor (PDGF β R) was shown to occur. The results show that the BPV-2 E5 oncoprotein binds to the activated form of the PDGF β receptor thus playing an important role in mesenchymal as well as epithelial carcinogenesis of the urinary bladder. Furthermore, these findings demonstrate that BPV-2 infects both epithelial and mesenchymal cells.

Bovine Papillomavirus Type 2 Infection and a Series of Mesenchymal Tumors of the Urinary Bladder in Cattle

PubMed Central

Martano, Manuela; Roperto, Franco; Russo, Valeria; Borzacchiello, Giuseppe; Paciello, Orlando; Iovane, Valentina; Leonardi, Leonardo; Maiolino, Paola; Restucci, Brunella; Papparella, Serenella; Roperto, Sante

2013-01-01

This report describes the histopathology of two hundred and fifty-three mesenchymal tumors of the urinary bladder in cattle grazing on lands rich in bracken fern. Approximately 80% were hemangiomas and angiosarcomas. Hemangioma (capillary, cavernous, and large vessels) was the most frequent mesenchymal tumor and was more common than angiosarcoma. Although the appearance of endothelial cells can vary remarkably, epithelioid angiosarcomas, often containing multinucleated cells, were the most frequent malignant vascular tumors. Hemangiopericytoma and tumors of muscle and soft connective tissue origin, alone and/or in association with tumor-like lesions, were less frequently seen. Furthermore, forty-five cases of intravascular papillary endothelial hyperplasia (IPEH), a lesion not previously reported in the urinary bladder of cattle, were also described. Bovine papillomavirus type-2 DNA was amplified in tumor samples. Forty vascular tumors were investigated by dual-labeling immunofluorescence, and, for the first time, a coexpression of E5 and platelet-derived growth factor β receptor (PDGFβR) was shown to occur. The results show that the BPV-2 E5 oncoprotein binds to the activated form of the PDGFβ receptor thus playing an important role in mesenchymal as well as epithelial carcinogenesis of the urinary bladder. Furthermore, these findings demonstrate that BPV-2 infects both epithelial and mesenchymal cells. PMID:23862156

The Trilateral Force: The Atlantic Alliance and the Future of Nuclear Weapons Strategy

DTIC Science & Technology

2013-12-03

Western World, Atlantic Council (2013), 46. s Paul Bracken, The Second Nuclear Age: Strategy, Danger, and the New Power Politics (New York: Times...Studies Institute (2013); Paul Bracken, "The Bomb Returns for a Second Act," Foreign Policy Research Institute E- Notes, November (2012). 11 David...Commission Report: Modernizing US. Nuclear Strategy, Force Structure and Posture, Global Zero (2012), 6. 27 Dana Johnson, et al., "Triad, Dyad, Monad

Analysis of Pteridium ribosomal RNA sequences by rapid direct sequencing.

PubMed

Tan, M K

1991-08-01

A total of 864 bases from 5 regions interspersed in the 18S and 26S rRNA molecules from various clones of Pteridium covering the general geographical distribution of the genus was analysed using a rapid rRNA sequencing technique. No base difference has been detected amongst the three major lineages, two of which apparently separated before the breakup of the ancient supercontinent, Pangaea. These regions of the rRNA sequences have thus been conserved for at least 160 million years and are here compared with other eukaryotic, especially plant rRNAs.

The Trilateral Force: The Atlantic Alliance and the Future of Nuclear Weapons Strategy

DTIC Science & Technology

2013-01-01

2010), 10. 4 Robert Manning, Envisioning 2030: U.S. Strategy for a Post-Western World, Atlantic Council (2013), 46. 5 Paul Bracken, The Second...Strategic Stability: Contending Interpretations, U.S. Army War College Strategic Studies Institute (2013); Paul Bracken, “The Bomb Returns for a Second...U.S. Nuclear Strategy, Force Structure and Posture, Global Zero (2012), 6. 27 Dana Johnson, et al., “Triad, Dyad, Monad? Shaping the U.S. Force of

Acid rain research program. Annual progress report, September 1975--June 1976

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

Evans, L.S.; Raynor, G.S.

1976-09-01

The aims of the research program are: (a) to observe the minimum threshold dose of simulated acid rain to produce visual and histological effects on plant foliage, (b) approach threshold limits of simulated sulfate acid rain that affect plant growth and reproduction, and (c) to measure chemical and meteorological parameters of incident rain. Acute leaf injury to several plant species resulted from exposure of foliage to simulated sulfate acid rain of pH level 2.3 to 2.9. Only slight injury occurred at 3.1. Scanning electron micrographs showed that injury to upper leaf surfaces occurred mostly at the base of trichomes (leafmore » hairs) and near stomata. An association of lesion development near vascular tissue was also noted. Histologically, lesions are characterized by an initial collapse of the epidermis with eventual lysis and collapse of more internal leaf tissues on the upper leaf surface of pinto beans which complemented detailed descriptions of visual lesion development after daily exposures to simulated rain. Initial experiments with gametophytes of Pteridium aquilinum show that reproduction of this fern species is very sensitive to solutions of pH 5.2 while vegetative development is not affected at pH levels of 2.2. Initial rain samples from the sequential sampler have been obtained. Initial portions of rain events exhibit a pH near 3.0 in some cases. More complete chemical analyses are anticipated.« less

Land-use induced dynamics of C, N and P in mountain soils of South Ecuador

NASA Astrophysics Data System (ADS)

Hamer, U.; Potthast, K.; Makeschin, F.

2009-04-01

The mountain rainforest region in South Ecuador is characterised by sites subjected to forest clearing by slash burn for pasture production. Repeated burning of pastures is a common management practice in South Ecuador. With ongoing pasture age bracken (Pteridium arachnoideum) outcompetes the pasture grass (Setaria sphacelata), pastures are abandoned and a vegetation succession develops. Along a land-use gradient (natural forest, young and old pasture, abandoned pasture with successional vegetation) the dynamics of C, N and P in the mountain soils were investigated. The study sites were located close to the "Estacion Científica San Francisco", about halfway between the province capitals Loja and Zamora, in the Cordillera Real, an eastern range of the South Ecuadorian Andes at about 2000 m above sea level. The mean annual air temperature is 15.3°C with an average annual rainfall of 2176 mm. The land-use change induced an increase of total P in the top soil (0-30 cm) of young and old pastures. An increase in SOC stocks in the top soil of the old pasture was combined with an increase in the proportion of NaOH extractable organic P. In the young pasture soil the mineralization of SOC and the amounts of microbial biomass C, N and P were highest. In 0-5 cm depth gross N mineralization and gross NH4 consumption rates were significantly higher in the young pasture compared to forest and abandoned pasture. Thus, the initial increase in microbial activity after forest to pasture conversion seems to slow down with increasing pasture age. Burning on the abandoned pasture site induced a short-term and short-lived increase in gross N mineralization rates. First results indicate that the land-use induced changes in mineralization rates were connected with changes in the microbial community structure.

Bovine Papillomavirus Type 13 Expression in the Urothelial Bladder Tumours of Cattle.

PubMed

Roperto, S; Russo, V; Leonardi, L; Martano, M; Corrado, F; Riccardi, M G; Roperto, F

2016-12-01

Bovine papillomavirus type 13 (BPV-13), a novel Deltapapillomavirus, has been found associated with urothelial tumours of the urinary bladder of cattle grazing on lands infested with bracken fern. BPV-13 was detected in 28 of 39 urothelial tumours. Diagnosis was based on sequencing of L1 and E5 amplicons from tumour samples. The nucleotide sequences generated from these amplicons showed a 100% homology with the sequences of BPV-13 L1 and E5 DNA found in Brazil from a fibropapilloma of the ear in a cow and from equine sarcoids in two horses. GenBank accession number of our representative BPV-13 sequences is JQ798171.1. Furthermore, mRNA encoding BPV-13 E5 oncoprotein was also documented, and its expression was also shown by immunohistochemistry and immunofluorescence in the basal and suprabasal urothelial tumour cells. In twenty-three tumours, BPV-13 was simultaneously found with BPV-2, a Deltapapillomavirus genus, species 4. The latter virus was detected by amplifying and sequencing a 154-bp-sized DNA fragment of BPV-2 E5. In addition, BPV-13 by itself was seen to be expressed in five BPV-2-negative urothelial tumours. This study shows that BPV-13 is present in urothelial tumour cells thus sharing biological properties with BPV-1 and BPV-2. Although further studies are needed, BPV-13 appears to be another worldwide infectious agent responsible for a distressing disease causing severe economic losses in cattle industry. © 2015 Blackwell Verlag GmbH.

Ecological legacies of Indigenous fire management in high-latitude coastal temperate rainforests, Canada

NASA Astrophysics Data System (ADS)

Hoffman, K.; Lertzman, K. P.; Starzomski, B. M.

2016-12-01

Anthropogenic burning is considered to have little impact on coastal temperate rainforest fire regimes in the Pacific Northwest (PNW) of North America, yet few long-term fire histories have been reconstructed in these forests. We use a multidisciplinary approach to reconstruct the ecological impact, scale, and legacies of historic fire regime variability in high-latitude coastal temperate rainforests located in British Columbia, Canada. We map seven centuries of fire activity with fire scars and records of stand establishment, and examine patterns in the distribution and composition of vegetation to assess whether fire was historically used as a tool for resource management. We conduct a paired study of 20 former Indigenous habitation and control sites across a 100 km2 island group to relate historic fire activity with long-term patterns of human land use and contemporary lightning strike densities. Fires were significantly associated with the locations of former Indigenous habitation sites, low and mixed in severity, and likely intentionally used to influence the composition and structure of vegetation, thus increasing the productivity of culturally important plants such as western redcedar, berry-producing shrubs, and bracken fern. Centuries of repeated anthropogenic burning have resulted in a mosaic of vegetation types in different stages of succession. These data are directly relevant to the management of contemporary forests as they do not support the widespread contention that old growth coastal temperate rainforests in this region are pristine landscapes where fire is rare, but more likely the result of long-term human land use practices.

Stoichiometry of ferns in Hawaii: implications for nutrient cycling.

PubMed

Amatangelo, Kathryn L; Vitousek, Peter M

2008-10-01

We asked if element concentrations in ferns differ systematically from those in woody dicots in ways that could influence ecosystem properties and processes. Phylogenetically, ferns are deeply separated from angiosperms; for our analyses we additionally separated leptosporangiate ferns into polypod ferns, a monophyletic clade of ferns which radiated after the rise of angiosperms, and all other leptosporangiate (non-polypod) ferns. We sampled both non-polypod and polypod ferns on a natural fertility gradient and within fertilized and unfertilized plots in Hawaii, and compared our data with shrub and tree samples collected previously in the same plots. Non-polypod ferns in particular had low Ca concentrations under all conditions and less plasticity in their N and P stoichiometry than did polypod ferns or dicots. Polypod ferns were particularly rich in N and P, with low N:P ratios, and their stoichiometry varied substantially in response to differences in nutrient availability. Distinguishing between these two groups has the potential to be useful both in and out of Hawaii, as they have distinct properties which can affect ecosystem function. These differences could contribute to the widespread abundance of polypod ferns in an angiosperm-dominated world, and to patterns of nutrient cycling and limitation in sites where ferns are abundant.

Between Two Fern Genomes

PubMed Central

2014-01-01

Ferns are the only major lineage of vascular plants not represented by a sequenced nuclear genome. This lack of genome sequence information significantly impedes our ability to understand and reconstruct genome evolution not only in ferns, but across all land plants. Azolla and Ceratopteris are ideal and complementary candidates to be the first ferns to have their nuclear genomes sequenced. They differ dramatically in genome size, life history, and habit, and thus represent the immense diversity of extant ferns. Together, this pair of genomes will facilitate myriad large-scale comparative analyses across ferns and all land plants. Here we review the unique biological characteristics of ferns and describe a number of outstanding questions in plant biology that will benefit from the addition of ferns to the set of taxa with sequenced nuclear genomes. We explain why the fern clade is pivotal for understanding genome evolution across land plants, and we provide a rationale for how knowledge of fern genomes will enable progress in research beyond the ferns themselves. PMID:25324969

Complete chloroplast genome sequence of a tree fern Alsophila spinulosa: insights into evolutionary changes in fern chloroplast genomes.

PubMed

Gao, Lei; Yi, Xuan; Yang, Yong-Xia; Su, Ying-Juan; Wang, Ting

2009-06-11

Ferns have generally been neglected in studies of chloroplast genomics. Before this study, only one polypod and two basal ferns had their complete chloroplast (cp) genome reported. Tree ferns represent an ancient fern lineage that first occurred in the Late Triassic. In recent phylogenetic analyses, tree ferns were shown to be the sister group of polypods, the most diverse group of living ferns. Availability of cp genome sequence from a tree fern will facilitate interpretation of the evolutionary changes of fern cp genomes. Here we have sequenced the complete cp genome of a scaly tree fern Alsophila spinulosa (Cyatheaceae). The Alsophila cp genome is 156,661 base pairs (bp) in size, and has a typical quadripartite structure with the large (LSC, 86,308 bp) and small single copy (SSC, 21,623 bp) regions separated by two copies of an inverted repeat (IRs, 24,365 bp each). This genome contains 117 different genes encoding 85 proteins, 4 rRNAs and 28 tRNAs. Pseudogenes of ycf66 and trnT-UGU are also detected in this genome. A unique trnR-UCG gene (derived from trnR-CCG) is found between rbcL and accD. The Alsophila cp genome shares some unusual characteristics with the previously sequenced cp genome of the polypod fern Adiantum capillus-veneris, including the absence of 5 tRNA genes that exist in most other cp genomes. The genome shows a high degree of synteny with that of Adiantum, but differs considerably from two basal ferns (Angiopteris evecta and Psilotum nudum). At one endpoint of an ancient inversion we detected a highly repeated 565-bp-region that is absent from the Adiantum cp genome. An additional minor inversion of the trnD-GUC, which is possibly shared by all ferns, was identified by comparison between the fern and other land plant cp genomes. By comparing four fern cp genome sequences it was confirmed that two major rearrangements distinguish higher leptosporangiate ferns from basal fern lineages. The Alsophila cp genome is very similar to that of the polypod fern Adiantum in terms of gene content, gene order and GC content. However, there exist some striking differences between them: the trnR-UCG gene represents a putative molecular apomorphy of tree ferns; and the repeats observed at one inversion endpoint may be a vestige of some unknown rearrangement(s). This work provided fresh insights into the fern cp genome evolution as well as useful data for future phylogenetic studies.

FERN Ethnomedicinal Plant Database: Exploring Fern Ethnomedicinal Plants Knowledge for Computational Drug Discovery.

PubMed

Thakar, Sambhaji B; Ghorpade, Pradnya N; Kale, Manisha V; Sonawane, Kailas D

2015-01-01

Fern plants are known for their ethnomedicinal applications. Huge amount of fern medicinal plants information is scattered in the form of text. Hence, database development would be an appropriate endeavor to cope with the situation. So by looking at the importance of medicinally useful fern plants, we developed a web based database which contains information about several group of ferns, their medicinal uses, chemical constituents as well as protein/enzyme sequences isolated from different fern plants. Fern ethnomedicinal plant database is an all-embracing, content management web-based database system, used to retrieve collection of factual knowledge related to the ethnomedicinal fern species. Most of the protein/enzyme sequences have been extracted from NCBI Protein sequence database. The fern species, family name, identification, taxonomy ID from NCBI, geographical occurrence, trial for, plant parts used, ethnomedicinal importance, morphological characteristics, collected from various scientific literatures and journals available in the text form. NCBI's BLAST, InterPro, phylogeny, Clustal W web source has also been provided for the future comparative studies. So users can get information related to fern plants and their medicinal applications at one place. This Fern ethnomedicinal plant database includes information of 100 fern medicinal species. This web based database would be an advantageous to derive information specifically for computational drug discovery, botanists or botanical interested persons, pharmacologists, researchers, biochemists, plant biotechnologists, ayurvedic practitioners, doctors/pharmacists, traditional medicinal users, farmers, agricultural students and teachers from universities as well as colleges and finally fern plant lovers. This effort would be useful to provide essential knowledge for the users about the adventitious applications for drug discovery, applications, conservation of fern species around the world and finally to create social awareness.

FTIR and py-GC-MS spectra of true-fern and seed-fern sphenopterids (Sydney Coalfield, Nova Scotia, Canada, Pennsylvanian)

USGS Publications Warehouse

Zodrow, E.L.; Mastalerz, Maria

2002-01-01

Sphenopterid specimens from the Late Pennsylvanian of Sydney Coalfield, Canada, are investigated by FTIR and py-GC-MS techniques as part of an on-going research project into the biochemistry and chemotaxonomy of Pennsylvanian-age pteridophylls. Included in the investigation are samples of the true-fern species Oligocarpia brongniartii and Zeilleria delicatula that are preserved as naturally macerated cuticles (NMC), and the seed-fern Eusphenopteris neuropteroides that is also preserved as a compression/impression. FTIR spectra of NMC seed-fern E. neuropteroides, and fern sphenopterid O. brongniartii are very similar, except that the latter does not have aromatic bands in the 700-900 cm-1 out-of-plane region, py-GC-MS show more aromatic compounds for the seed fern than for the two true-fern sphenopterids. Another difference between seed-fern and true-fern sphenopterids is a lower ratio of CH2 to CH3 in chemically treated specimens (CTC) for the seed fern. These observations suggest slightly higher aromaticity for the seed ferns, perhaps related to some chemotaxonomic differences. Comparison of FTIR and py-GC-MS characteristics of sphenopterids and other plant groups shows that these two techniques have potential to identifying chemotaxonomic signals from Carboniferous pteridophylls in general, although more data are needed to confirm this. ?? 2002 Elsevier Science B.V. All rights reserved.

Ferns diversified in the shadow of angiosperms.

PubMed

Schneider, Harald; Schuettpelz, Eric; Pryer, Kathleen M; Cranfill, Raymond; Magallón, Susana; Lupia, Richard

2004-04-01

The rise of angiosperms during the Cretaceous period is often portrayed as coincident with a dramatic drop in the diversity and abundance of many seed-free vascular plant lineages, including ferns. This has led to the widespread belief that ferns, once a principal component of terrestrial ecosystems, succumbed to the ecological predominance of angiosperms and are mostly evolutionary holdovers from the late Palaeozoic/early Mesozoic era. The first appearance of many modern fern genera in the early Tertiary fossil record implies another evolutionary scenario; that is, that the majority of living ferns resulted from a more recent diversification. But a full understanding of trends in fern diversification and evolution using only palaeobotanical evidence is hindered by the poor taxonomic resolution of the fern fossil record in the Cretaceous. Here we report divergence time estimates for ferns and angiosperms based on molecular data, with constraints from a reassessment of the fossil record. We show that polypod ferns (> 80% of living fern species) diversified in the Cretaceous, after angiosperms, suggesting perhaps an ecological opportunistic response to the diversification of angiosperms, as angiosperms came to dominate terrestrial ecosystems.

Ferns of the Blue Ridge

Treesearch

Arnold Krochmal; Connie Krochmal

1979-01-01

The forests and open fields of the Blue Ridge provide ideal growing conditions for a number of ferns. Since some of these are evergreen, ferns can be seen in the area during every month of the year. Ferns are old members of the plant kingdom, and fossil ancestors are common in slate, shale, and coal. All ferns belong to the Pteridophytes, a group that also includes...

Identifying appropriate protected areas for endangered fern species under climate change.

PubMed

Wang, Chun-Jing; Wan, Ji-Zhong; Zhang, Zhi-Xiang; Zhang, Gang-Min

2016-01-01

The management of protected areas (PAs) is widely used in the conservation of endangered plant species under climate change. However, studies that have identified appropriate PAs for endangered fern species are rare. To address this gap, we must develop a workflow to plan appropriate PAs for endangered fern species that will be further impacted by climate change. Here, we used endangered fern species in China as a case study, and we applied conservation planning software coupled with endangered fern species distribution data and distribution modeling to plan conservation areas with high priority protection needs under climate change. We identified appropriate PAs for endangered fern species under climate change based on the IUCN protected area categories (from Ia to VI) and planned additional PAs for endangered fern species. The high priority regions for protecting the endangered fern species were distributed throughout southern China. With decreasing temperature seasonality, the priority ranking of all endangered fern species is projected to increase in existing PAs. Accordingly, we need to establish conservation areas with low climate vulnerability in existing PAs and expand the conservation areas for endangered fern species in the high priority conservation regions.

Fern Gametophytes in Culture--A Simple System for Studying Plant Development and Reproduction.

ERIC Educational Resources Information Center

Dyer, A. F.

1983-01-01

Discusses fern life cycle and basic techniques for culturing fern gametophytes in the classroom. Also discusses investigations into the reproductive biology of ferns and into the early development of gametophytes. (JN)

Leaf evolution in early-diverging ferns: insights from a new fern-like plant from the Late Devonian of China

PubMed Central

Wang, De-Ming; Xu, Hong-He; Xue, Jin-Zhuang; Wang, Qi; Liu, Le

2015-01-01

Background and Aims With the exception of angiosperms, the main euphyllophyte lineages (i.e. ferns sensu lato, progymnosperms and gymnosperms) had evolved laminate leaves by the Late Devonian. The evolution of laminate leaves, however, remains unclear for early-diverging ferns, largely represented by fern-like plants. This study presents a novel fern-like taxon with pinnules, which provides new insights into the early evolution of laminate leaves in early-diverging ferns. Methods Macrofossil specimens were collected from the Upper Devonian (Famennian) Wutong Formation of Anhui and Jiangsu Provinces, South China. A standard degagement technique was employed to uncover compressed plant portions within the rock matrix. Key Results A new fern-like taxon, Shougangia bella gen. et sp. nov., is described and represents an early-diverging fern with highly derived features. It has a partially creeping stem with adventitious roots only on one side, upright primary and secondary branches arranged in helices, tertiary branches borne alternately or (sub)oppositely, laminate and usually lobed leaves with divergent veins, and complex fertile organs terminating tertiary branches and possessing multiple divisions and numerous terminal sporangia. Conclusions Shougangia bella provides unequivocal fossil evidence for laminate leaves in early-diverging ferns. It suggests that fern-like plants, along with other euphyllophyte lineages, had independently evolved megaphylls by the Late Devonian, possibly in response to a significant decline in atmospheric CO2 concentration. Among fern-like plants, planate ultimate appendages are homologous with laminate pinnules, and in the evolution of megaphylls, fertile organs tend to become complex. PMID:25979918

Structure-function constraints of tracheid-based xylem: a comparison of conifers and ferns.

PubMed

Pittermann, Jarmila; Limm, Emily; Rico, Christopher; Christman, Mairgareth A

2011-10-01

The ferns comprise one of the most ancient tracheophytic plant lineages, and occupy habitats ranging from tundra to deserts and the equatorial tropics. Like their nearest relatives the conifers, modern ferns possess tracheid-based xylem but the structure-function relationships of fern xylem are poorly understood. Here, we sampled the fronds (megaphylls) of 16 species across the fern phylogeny, and examined the relationships among hydraulic transport, drought-induced cavitation resistance, the xylem anatomy of the stipe, and the gas-exchange response of the pinnae. For comparison, the results are presented alongside a similar suite of conifer data. Fern xylem is as resistant to cavitation as conifer xylem, but exhibits none of the hydraulic or structural trade-offs associated with resistance to cavitation. On a conduit diameter basis, fern xylem can exhibit greater hydraulic efficiency than conifer and angiosperm xylem. In ferns, wide and long tracheids compensate in part for the lack of secondary xylem and allow ferns to exhibit transport rates on a par with those of conifers. We suspect that it is the arrangement of the primary xylem, in addition to the intrinsic traits of the conduits themselves, that may help explain the broad range of cavitation resistance in ferns. © 2011 The Authors. New Phytologist © 2011 New Phytologist Trust.

Large-scale phylogenomic analysis resolves a backbone phylogeny in ferns.

PubMed

Shen, Hui; Jin, Dongmei; Shu, Jiang-Ping; Zhou, Xi-Le; Lei, Ming; Wei, Ran; Shang, Hui; Wei, Hong-Jin; Zhang, Rui; Liu, Li; Gu, Yu-Feng; Zhang, Xian-Chun; Yan, Yue-Hong

2018-02-01

Ferns, originated about 360 million years ago, are the sister group of seed plants. Despite the remarkable progress in our understanding of fern phylogeny, with conflicting molecular evidence and different morphological interpretations, relationships among major fern lineages remain controversial. With the aim to obtain a robust fern phylogeny, we carried out a large-scale phylogenomic analysis using high-quality transcriptome sequencing data, which covered 69 fern species from 38 families and 11 orders. Both coalescent-based and concatenation-based methods were applied to both nucleotide and amino acid sequences in species tree estimation. The resulting topologies are largely congruent with each other, except for the placement of Angiopteris fokiensis, Cheiropleuria bicuspis, Diplaziopsis brunoniana, Matteuccia struthiopteris, Elaphoglossum mcclurei, and Tectaria subpedata. Our result confirmed that Equisetales is sister to the rest of ferns, and Dennstaedtiaceae is sister to eupolypods. Moreover, our result strongly supported some relationships different from the current view of fern phylogeny, including that Marattiaceae may be sister to the monophyletic clade of Psilotaceae and Ophioglossaceae; that Gleicheniaceae and Hymenophyllaceae form a monophyletic clade sister to Dipteridaceae; and that Aspleniaceae is sister to the rest of the groups in eupolypods II. These results were interpreted with morphological traits, especially sporangia characters, and a new evolutionary route of sporangial annulus in ferns was suggested. This backbone phylogeny in ferns sets a foundation for further studies in biology and evolution in ferns, and therefore in plants. © The Authors 2017. Published by Oxford University Press.

Large-scale phylogenomic analysis resolves a backbone phylogeny in ferns

PubMed Central

Shen, Hui; Jin, Dongmei; Shu, Jiang-Ping; Zhou, Xi-Le; Lei, Ming; Wei, Ran; Shang, Hui; Wei, Hong-Jin; Zhang, Rui; Liu, Li; Gu, Yu-Feng; Zhang, Xian-Chun; Yan, Yue-Hong

2018-01-01

Abstract Background Ferns, originated about 360 million years ago, are the sister group of seed plants. Despite the remarkable progress in our understanding of fern phylogeny, with conflicting molecular evidence and different morphological interpretations, relationships among major fern lineages remain controversial. Results With the aim to obtain a robust fern phylogeny, we carried out a large-scale phylogenomic analysis using high-quality transcriptome sequencing data, which covered 69 fern species from 38 families and 11 orders. Both coalescent-based and concatenation-based methods were applied to both nucleotide and amino acid sequences in species tree estimation. The resulting topologies are largely congruent with each other, except for the placement of Angiopteris fokiensis, Cheiropleuria bicuspis, Diplaziopsis brunoniana, Matteuccia struthiopteris, Elaphoglossum mcclurei, and Tectaria subpedata. Conclusions Our result confirmed that Equisetales is sister to the rest of ferns, and Dennstaedtiaceae is sister to eupolypods. Moreover, our result strongly supported some relationships different from the current view of fern phylogeny, including that Marattiaceae may be sister to the monophyletic clade of Psilotaceae and Ophioglossaceae; that Gleicheniaceae and Hymenophyllaceae form a monophyletic clade sister to Dipteridaceae; and that Aspleniaceae is sister to the rest of the groups in eupolypods II. These results were interpreted with morphological traits, especially sporangia characters, and a new evolutionary route of sporangial annulus in ferns was suggested. This backbone phylogeny in ferns sets a foundation for further studies in biology and evolution in ferns, and therefore in plants. PMID:29186447

Leaf evolution in early-diverging ferns: insights from a new fern-like plant from the Late Devonian of China.

PubMed

Wang, De-Ming; Xu, Hong-He; Xue, Jin-Zhuang; Wang, Qi; Liu, Le

2015-06-01

With the exception of angiosperms, the main euphyllophyte lineages (i.e. ferns sensu lato, progymnosperms and gymnosperms) had evolved laminate leaves by the Late Devonian. The evolution of laminate leaves, however, remains unclear for early-diverging ferns, largely represented by fern-like plants. This study presents a novel fern-like taxon with pinnules, which provides new insights into the early evolution of laminate leaves in early-diverging ferns. Macrofossil specimens were collected from the Upper Devonian (Famennian) Wutong Formation of Anhui and Jiangsu Provinces, South China. A standard degagement technique was employed to uncover compressed plant portions within the rock matrix. A new fern-like taxon, SHOUGANGIA BELLA GEN ET SP NOV: , is described and represents an early-diverging fern with highly derived features. It has a partially creeping stem with adventitious roots only on one side, upright primary and secondary branches arranged in helices, tertiary branches borne alternately or (sub)oppositely, laminate and usually lobed leaves with divergent veins, and complex fertile organs terminating tertiary branches and possessing multiple divisions and numerous terminal sporangia. Shougangia bella provides unequivocal fossil evidence for laminate leaves in early-diverging ferns. It suggests that fern-like plants, along with other euphyllophyte lineages, had independently evolved megaphylls by the Late Devonian, possibly in response to a significant decline in atmospheric CO2 concentration. Among fern-like plants, planate ultimate appendages are homologous with laminate pinnules, and in the evolution of megaphylls, fertile organs tend to become complex. © The Author 2015. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Evolution of the rpoB-psbZ region in fern plastid genomes: notable structural rearrangements and highly variable intergenic spacers

PubMed Central

2011-01-01

Background The rpoB-psbZ (BZ) region of some fern plastid genomes (plastomes) has been noted to go through considerable genomic changes. Unraveling its evolutionary dynamics across all fern lineages will lead to clarify the fundamental process shaping fern plastome structure and organization. Results A total of 24 fern BZ sequences were investigated with taxon sampling covering all the extant fern orders. We found that: (i) a tree fern Plagiogyria japonica contained a novel gene order that can be generated from either the ancestral Angiopteris type or the derived Adiantum type via a single inversion; (ii) the trnY-trnE intergenic spacer (IGS) of the filmy fern Vandenboschia radicans was expanded 3-fold due to the tandem 27-bp repeats which showed strong sequence similarity with the anticodon domain of trnY; (iii) the trnY-trnE IGSs of two horsetail ferns Equisetum ramosissimum and E. arvense underwent an unprecedented 5-kb long expansion, more than a quarter of which was consisted of a single type of direct repeats also relevant to the trnY anticodon domain; and (iv) ycf66 has independently lost at least four times in ferns. Conclusions Our results provided fresh insights into the evolutionary process of fern BZ regions. The intermediate BZ gene order was not detected, supporting that the Adiantum type was generated by two inversions occurring in pairs. The occurrence of Vandenboschia 27-bp repeats represents the first evidence of partial tRNA gene duplication in fern plastomes. Repeats potentially forming a stem-loop structure play major roles in the expansion of the trnY-trnE IGS. PMID:21486489

Evolution of the rpoB-psbZ region in fern plastid genomes: notable structural rearrangements and highly variable intergenic spacers.

PubMed

Gao, Lei; Zhou, Yuan; Wang, Zhi-Wei; Su, Ying-Juan; Wang, Ting

2011-04-13

The rpoB-psbZ (BZ) region of some fern plastid genomes (plastomes) has been noted to go through considerable genomic changes. Unraveling its evolutionary dynamics across all fern lineages will lead to clarify the fundamental process shaping fern plastome structure and organization. A total of 24 fern BZ sequences were investigated with taxon sampling covering all the extant fern orders. We found that: (i) a tree fern Plagiogyria japonica contained a novel gene order that can be generated from either the ancestral Angiopteris type or the derived Adiantum type via a single inversion; (ii) the trnY-trnE intergenic spacer (IGS) of the filmy fern Vandenboschia radicans was expanded 3-fold due to the tandem 27-bp repeats which showed strong sequence similarity with the anticodon domain of trnY; (iii) the trnY-trnE IGSs of two horsetail ferns Equisetum ramosissimum and E. arvense underwent an unprecedented 5-kb long expansion, more than a quarter of which was consisted of a single type of direct repeats also relevant to the trnY anticodon domain; and (iv) ycf66 has independently lost at least four times in ferns. Our results provided fresh insights into the evolutionary process of fern BZ regions. The intermediate BZ gene order was not detected, supporting that the Adiantum type was generated by two inversions occurring in pairs. The occurrence of Vandenboschia 27-bp repeats represents the first evidence of partial tRNA gene duplication in fern plastomes. Repeats potentially forming a stem-loop structure play major roles in the expansion of the trnY-trnE IGS.

Phylogeny and evolution of ferns (monilophytes) with a focus on the early leptosporangiate divergences.

PubMed

Pryer, Kathleen M; Schuettpelz, Eric; Wolf, Paul G; Schneider, Harald; Smith, Alan R; Cranfill, Raymond

2004-10-01

The phylogenetic structure of ferns (= monilophytes) is explored here, with a special focus on the early divergences among leptosporangiate lineages. Despite considerable progress in our understanding of fern relationships, a rigorous and comprehensive analysis of the early leptosporangiate divergences was lacking. Therefore, a data set was designed here to include critical taxa that were not included in earlier studies. More than 5000 bp from the plastid (rbcL, atpB, rps4) and the nuclear (18S rDNA) genomes were sequenced for 62 taxa. Phylogenetic analyses of these data (1) confirm that Osmundaceae are sister to the rest of the leptosporangiates, (2) resolve a diverse set of ferns formerly thought to be a subsequent grade as possibly monophyletic (((Dipteridaceae, Matoniaceae), Gleicheniaceae), Hymenophyllaceae), and (3) place schizaeoid ferns as sister to a large clade of "core leptosporangiates" that includes heterosporous ferns, tree ferns, and polypods. Divergence time estimates for ferns are reported from penalized likelihood analyses of our molecular data, with constraints from a reassessment of the fossil record.

Photosynthesis, photoinhibition, and nitrogen use efficiency in native and invasive tree ferns in Hawaii.

PubMed

Durand, Leilani Z; Goldstein, Guillermo

2001-02-01

Photosynthetic gas exchange, chlorophyll fluorescence, nitrogen use efficiency, and related leaf traits of native Hawaiian tree ferns in the genus Cibotium were compared with those of the invasive Australian tree fern Sphaeropteris cooperi in an attempt to explain the higher growth rates of S. cooperi in Hawaii. Comparisons were made between mature sporophytes growing in the sun (gap or forest edge) and in shady understories at four sites at three different elevations. The invasive tree fern had 12-13 cm greater height increase per year and approximately 5 times larger total leaf surface area per plant compared to the native tree ferns. The maximum rates of photosynthesis of S. cooperi in the sun and shade were significantly higher than those of the native Cibotium spp (for example, 11.2 and 7.1 µmol m -2  s -1 , and 5.8 and 3.6 µmol m -2  s -1 respectively for the invasive and natives at low elevation). The instantaneous photosynthetic nitrogen use efficiency of the invasive tree fern was significantly higher than that of the native tree ferns, but when integrated over the life span of the frond the differences were not significant. The fronds of the invasive tree fern species had a significantly shorter life span than the native tree ferns (approximately 6 months and 12 months, respectively), and significantly higher nitrogen content per unit leaf mass. The native tree ferns growing in both sun and shade exhibited greater photoinhibition than the invasive tree fern after being experimentally subjected to high light levels. The native tree ferns recovered only 78% of their dark-acclimated quantum yield (F v /F m ), while the invasive tree fern recovered 90% and 86% of its dark-acclimated F v /F m when growing in sun and shade, respectively. Overall, the invasive tree fern appears to be more efficient at capturing and utilizing light than the native Cibotium species, particularly in high-light environments such as those associated with high levels of disturbance.

The potential of Thelypteris palustris and Asparagus sprengeri in phytoremediation of arsenic contamination.

PubMed

Anderson, LaShunda L; Walsh, Maud; Roy, Amitava; Bianchetti, Christopher M; Merchan, Gregory

2011-02-01

The potential of two plants, Thelypteris palustris (marsh fern) and Asparagus sprengeri (asparagus fern), for phytoremediation of arsenic contamination was evaluated. The plants were chosen for this study because of the discovery of the arsenic hyperaccumulating fern, Pteris vittata (Ma et al., 2001) and previous research indicating asparagus fern's ability to tolerate > 1200 ppm soil arsenic. Objectives were (1) to assess if selected plants are arsenic hyperaccumulators; and (2) to assess changes in the species of arsenic upon accumulation in selected plants. Greenhouse hydroponic experiments arsenic treatment levels were established by adding potassium arsenate to solution. All plants were placed into the hydroponic experiments while still potted in their growth media. Marsh fern and Asparagus fern can both accumulate arsenic. Marsh fern bioaccumulation factors (> 10) are in the range of known hyperaccumulator, Pteris vittata Therefore, Thelypteris palustris is may be a good candidate for remediation of arsenic soil contamination levels of < or = 500 microg/L arsenic. Total oxidation of As (III) to As (V) does not occur in asparagus fern. The asparagus fern is arsenic tolerant (bioaccumulation factors < 10), but is not considered a good potential phytoremediation candidate.

Plastome Sequences of Lygodium japonicum and Marsilea crenata Reveal the Genome Organization Transformation from Basal Ferns to Core Leptosporangiates

PubMed Central

Gao, Lei; Wang, Bo; Wang, Zhi-Wei; Zhou, Yuan; Su, Ying-Juan; Wang, Ting

2013-01-01

Previous studies have shown that core leptosporangiates, the most species-rich group of extant ferns (monilophytes), have a distinct plastid genome (plastome) organization pattern from basal fern lineages. However, the details of genome structure transformation from ancestral ferns to core leptosporangiates remain unclear because of limited plastome data available. Here, we have determined the complete chloroplast genome sequences of Lygodium japonicum (Lygodiaceae), a member of schizaeoid ferns (Schizaeales), and Marsilea crenata (Marsileaceae), a representative of heterosporous ferns (Salviniales). The two species represent the sister and the basal lineages of core leptosporangiates, respectively, for which the plastome sequences are currently unavailable. Comparative genomic analysis of all sequenced fern plastomes reveals that the gene order of L. japonicum plastome occupies an intermediate position between that of basal ferns and core leptosporangiates. The two exons of the fern ndhB gene have a unique pattern of intragenic copy number variances. Specifically, the substitution rate heterogeneity between the two exons is congruent with their copy number changes, confirming the constraint role that inverted repeats may play on the substitution rate of chloroplast gene sequences. PMID:23821521

75 FR 23151 - Noxious Weeds; Old World Climbing Fern and Maidenhair Creeper

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-03

.... APHIS-2008-0097] Noxious Weeds; Old World Climbing Fern and Maidenhair Creeper AGENCY: Animal and Plant... adding Old World climbing fern (Lygodium microphyllum (Cavanilles) R. Brown) and maidenhair creeper... amended the regulations by adding Old World climbing fern (Lygodium microphyllum (Cavanilles) R. Brown...

Leaf Photosynthetic Rate of Tropical Ferns Is Evolutionarily Linked to Water Transport Capacity

PubMed Central

Cao, Kun-Fang; Hu, Hong; Zhang, Jiao-Lin

2014-01-01

Ferns usually have relatively lower photosynthetic potential than angiosperms. However, it is unclear whether low photosynthetic potential of ferns is linked to leaf water supply. We hypothesized that there is an evolutionary association of leaf water transport capacity with photosynthesis and stomatal density in ferns. In the present study, a series of functional traits relating to leaf anatomy, hydraulics and physiology were assessed in 19 terrestrial and 11 epiphytic ferns in a common garden, and analyzed by a comparative phylogenetics method. Compared with epiphytic ferns, terrestrial ferns had higher vein density (Dvein), stomatal density (SD), stomatal conductance (gs), and photosynthetic capacity (Amax), but lower values for lower epidermal thickness (LET) and leaf thickness (LT). Across species, all traits varied significantly, but only stomatal length (SL) showed strong phylogenetic conservatism. Amax was positively correlated with Dvein and gs with and without phylogenetic corrections. SD correlated positively with Amax, Dvein and gs, with the correlation between SD and Dvein being significant after phylogenetic correction. Leaf water content showed significant correlations with LET, LT, and mesophyll thickness. Our results provide evidence that Amax of the studied ferns is linked to leaf water transport capacity, and there was an evolutionary association between water supply and demand in ferns. These findings add new insights into the evolutionary correlations among traits involving carbon and water economy in ferns. PMID:24416265

The evolution, morphology, and development of fern leaves

PubMed Central

Vasco, Alejandra; Moran, Robbin C.; Ambrose, Barbara A.

2013-01-01

Leaves are lateral determinate structures formed in a predictable sequence (phyllotaxy) on the flanks of an indeterminate shoot apical meristem. The origin and evolution of leaves in vascular plants has been widely debated. Being the main conspicuous organ of nearly all vascular plants and often easy to recognize as such, it seems surprising that leaves have had multiple origins. For decades, morphologists, anatomists, paleobotanists, and systematists have contributed data to this debate. More recently, molecular genetic studies have provided insight into leaf evolution and development mainly within angiosperms and, to a lesser extent, lycophytes. There has been recent interest in extending leaf evolutionary developmental studies to other species and lineages, particularly in lycophytes and ferns. Therefore, a review of fern leaf morphology, evolution and development is timely. Here we discuss the theories of leaf evolution in ferns, morphology, and diversity of fern leaves, and experimental results of fern leaf development. We summarize what is known about the molecular genetics of fern leaf development and what future studies might tell us about the evolution of fern leaf development. PMID:24027574

Contribution of species-specific chemical signatures to soil organic matter in Kohala, HI.

NASA Astrophysics Data System (ADS)

Stewart, C. E.; Amatangelo, K.; Neff, J. C.

2008-12-01

Soil organic matter (SOM) inherits much of its chemical structure from the dominant vegetation, including phenolic (lignin-derived), aromatic, and aliphatic (cutin and wax-derived) compounds. The Hawaiian fern species Dicranopteris decomposes more slowly than the angiosperm, Cheirodendron due to high concentrations of recalcitrant C compounds. These aliphatic fern leaf waxes are well-preserved and may comprise a large portion of the recalcitrant organic matter in these soils. Our objective was to determine the chemical signature of fern and angiosperm vegetation types and trace the preservation or loss of those compounds into the soil. We collected live tissue, litter, roots, and soil (<53 μm) from five dominant vegetation types including two angiosperms Cheirodendron and Metrosideros, two basal ferns Dicranopteris and Cibotium and a polypod fern Diplazium in Kohala, HI. We characterized them via TMAH-pyrolysis-gas chromatography-mass spectrometry. We found distinct chemical differences between angiosperm and fern vegetation; angiosperm contained more G- and S-derived lignin structures and the fern species contained greater relative abundances of P-derived lignin and tannin-derivatives. There was a general decrease of lignin-derived phenolic compounds from live to litter to soils and an increase in more recalcitrant, aromatic and aliphatic C. Recalcitrant fern-derived cutin and leaf waxes (alkene and alkanes structures) were evident in the soils, but clear species differences were not observed. Although ferns contain distinct lipid and wax-derived compounds, soils developed under fern do not appear to accumulate these compounds in SOM.

Not only in the temperate zone: independent gametophytes of two vittarioid ferns (Pteridaceae, Polypodiales) in East Asian subtropics.

PubMed

Kuo, Li-Yaung; Chen, Cheng-Wei; Shinohara, Wataru; Ebihara, Atsushi; Kudoh, Hiroshi; Sato, Hirotoshi; Huang, Yao-Moan; Chiou, Wen-Liang

2017-03-01

Independent gametophyte ferns are unique among vascular plants because they are sporophyteless and reproduce asexually to maintain their populations in the gametophyte generation. Such ferns had been primarily discovered in temperate zone, and usually hypothesized with (sub)tropical origins and subsequent extinction of sporophyte due to climate change during glaciations. Presumably, independent fern gametophytes are unlikely to be distributed in tropics and subtropics because of relatively stable climates which are less affected by glaciations. Nonetheless, the current study presents cases of two independent gametophyte fern species in subtropic East Asia. In this study, we applied plastid DNA sequences (trnL-L-F and matK + ndhF + chlL datasets) and comprehensive sampling (~80%) of congeneric species for molecular identification and divergence time estimation of these independent fern gametophytes. The two independent gametophyte ferns were found belonging to genus Haplopteris (vittarioids, Pteridaceae) and no genetic identical sporophyte species in East Asia. For one species, divergence times between its populations imply recent oversea dispersal(s) by spores occurred during Pleistocene. By examining their ex situ and in situ fertility, prezygotic sterility was found in these two Haplopteris, in which gametangia were not or very seldom observed, and this prezygotic sterility might attribute to their lacks of functional sporophytes. Our field observation and survey on their habitats suggest microhabitat conditions might attribute to this prezygotic sterility. These findings point to consideration of whether recent climate change during the Pleistocene glaciation resulted in ecophysiological maladaptation of non-temperate independent gametophyte ferns. In addition, we provided a new definition to classify fern gametophyte independences at the population level. We expect that continued investigations into tropical and subtropical fern gametophyte floras will further illustrate the biogeographic significance of non-temperate fern gametophyte independence.

Chloroplast Genome Evolution in Early Diverged Leptosporangiate Ferns

PubMed Central

Kim, Hyoung Tae; Chung, Myong Gi; Kim, Ki-Joong

2014-01-01

In this study, the chloroplast (cp) genome sequences from three early diverged leptosporangiate ferns were completed and analyzed in order to understand the evolution of the genome of the fern lineages. The complete cp genome sequence of Osmunda cinnamomea (Osmundales) was 142,812 base pairs (bp). The cp genome structure was similar to that of eusporangiate ferns. The gene/intron losses that frequently occurred in the cp genome of leptosporangiate ferns were not found in the cp genome of O. cinnamomea. In addition, putative RNA editing sites in the cp genome were rare in O. cinnamomea, even though the sites were frequently predicted to be present in leptosporangiate ferns. The complete cp genome sequence of Diplopterygium glaucum (Gleicheniales) was 151,007 bp and has a 9.7 kb inversion between the trnL-CAA and trnV-GCA genes when compared to O. cinnamomea. Several repeated sequences were detected around the inversion break points. The complete cp genome sequence of Lygodium japonicum (Schizaeales) was 157,142 bp and a deletion of the rpoC1 intron was detected. This intron loss was shared by all of the studied species of the genus Lygodium. The GC contents and the effective numbers of co-dons (ENCs) in ferns varied significantly when compared to seed plants. The ENC values of the early diverged leptosporangiate ferns showed intermediate levels between eusporangiate and core leptosporangiate ferns. However, our phylogenetic tree based on all of the cp gene sequences clearly indicated that the cp genome similarity between O. cinnamomea (Osmundales) and eusporangiate ferns are symplesiomorphies, rather than synapomorphies. Therefore, our data is in agreement with the view that Osmundales is a distinct early diverged lineage in the leptosporangiate ferns. PMID:24823358

Chloroplast genome evolution in early diverged leptosporangiate ferns.

PubMed

Kim, Hyoung Tae; Chung, Myong Gi; Kim, Ki-Joong

2014-05-01

In this study, the chloroplast (cp) genome sequences from three early diverged leptosporangiate ferns were completed and analyzed in order to understand the evolution of the genome of the fern lineages. The complete cp genome sequence of Osmunda cinnamomea (Osmundales) was 142,812 base pairs (bp). The cp genome structure was similar to that of eusporangiate ferns. The gene/intron losses that frequently occurred in the cp genome of leptosporangiate ferns were not found in the cp genome of O. cinnamomea. In addition, putative RNA editing sites in the cp genome were rare in O. cinnamomea, even though the sites were frequently predicted to be present in leptosporangiate ferns. The complete cp genome sequence of Diplopterygium glaucum (Gleicheniales) was 151,007 bp and has a 9.7 kb inversion between the trnL-CAA and trnVGCA genes when compared to O. cinnamomea. Several repeated sequences were detected around the inversion break points. The complete cp genome sequence of Lygodium japonicum (Schizaeales) was 157,142 bp and a deletion of the rpoC1 intron was detected. This intron loss was shared by all of the studied species of the genus Lygodium. The GC contents and the effective numbers of codons (ENCs) in ferns varied significantly when compared to seed plants. The ENC values of the early diverged leptosporangiate ferns showed intermediate levels between eusporangiate and core leptosporangiate ferns. However, our phylogenetic tree based on all of the cp gene sequences clearly indicated that the cp genome similarity between O. cinnamomea (Osmundales) and eusporangiate ferns are symplesiomorphies, rather than synapomorphies. Therefore, our data is in agreement with the view that Osmundales is a distinct early diverged lineage in the leptosporangiate ferns.

A Catskill Flora and Economic Botany, I: Pteridophyta. The Ferns and Fern Allies. Bulletin No. 438, New York State Museum.

ERIC Educational Resources Information Center

Brooks, Karl L.

The information contained within this guide about flora of the ferns and fern allies of the Catskill Mountains of New York State covers medical and food uses of the plants, as well as the more typical floristic data of keys, drawings, and plant descriptions. (CS)

A Mutant Hunt Using the C-Fern (Ceratopteris Richardii)

ERIC Educational Resources Information Center

Calie, Patrick J.

2005-01-01

A modification of the popular C-Fern system, the tropical fern Ceratopteris richardii is developed in which students plate out a genetically mixed set of fern spores and then select for specific mutants. This exercise can provide students with an experience in plant mutant selection and can be used as a platform to expose students to a diverse…

Effects of hayscented fern density and light on white ash seedling growth

Treesearch

Tracy E. Hippensteel; Todd W. Bowersox

1995-01-01

Communities of hayscented ferns [Dennstaedtia punctilobula (Michx.) Moore] are present in many forested areas of Pennsylvania. These ferns can reduce the number and height growth of desirable tree seedlings. A study was conducted to determine the effects of fern frond density on the stem growth and leaf development of bare-root planted white ash (...

Ptaquiloside reduces NK cell activities by enhancing metallothionein expression, which is prevented by selenium

USDA-ARS?s Scientific Manuscript database

Pteridium aquilinum, one of the most important poisonous plants in the world, is known to be carcinogenic to animals and humans. Moreover, our previous studies showed that the immunosuppressive effects of ptaquiloside, its main toxic agent, were prevented by selenium in mouse natural killer (NK) cel...

The evolutionary history of ferns inferred from 25 low-copy nuclear genes.

PubMed

Rothfels, Carl J; Li, Fay-Wei; Sigel, Erin M; Huiet, Layne; Larsson, Anders; Burge, Dylan O; Ruhsam, Markus; Deyholos, Michael; Soltis, Douglas E; Stewart, C Neal; Shaw, Shane W; Pokorny, Lisa; Chen, Tao; dePamphilis, Claude; DeGironimo, Lisa; Chen, Li; Wei, Xiaofeng; Sun, Xiao; Korall, Petra; Stevenson, Dennis W; Graham, Sean W; Wong, Gane K-S; Pryer, Kathleen M

2015-07-01

• Understanding fern (monilophyte) phylogeny and its evolutionary timescale is critical for broad investigations of the evolution of land plants, and for providing the point of comparison necessary for studying the evolution of the fern sister group, seed plants. Molecular phylogenetic investigations have revolutionized our understanding of fern phylogeny, however, to date, these studies have relied almost exclusively on plastid data.• Here we take a curated phylogenomics approach to infer the first broad fern phylogeny from multiple nuclear loci, by combining broad taxon sampling (73 ferns and 12 outgroup species) with focused character sampling (25 loci comprising 35877 bp), along with rigorous alignment, orthology inference and model selection.• Our phylogeny corroborates some earlier inferences and provides novel insights; in particular, we find strong support for Equisetales as sister to the rest of ferns, Marattiales as sister to leptosporangiate ferns, and Dennstaedtiaceae as sister to the eupolypods. Our divergence-time analyses reveal that divergences among the extant fern orders all occurred prior to ∼200 MYA. Finally, our species-tree inferences are congruent with analyses of concatenated data, but generally with lower support. Those cases where species-tree support values are higher than expected involve relationships that have been supported by smaller plastid datasets, suggesting that deep coalescence may be reducing support from the concatenated nuclear data.• Our study demonstrates the utility of a curated phylogenomics approach to inferring fern phylogeny, and highlights the need to consider underlying data characteristics, along with data quantity, in phylogenetic studies. © 2015 Botanical Society of America, Inc.

Horizontal transfer of an adaptive chimeric photoreceptor from bryophytes to ferns

PubMed Central

Li, Fay-Wei; Villarreal, Juan Carlos; Kelly, Steven; Rothfels, Carl J.; Melkonian, Michael; Frangedakis, Eftychios; Ruhsam, Markus; Sigel, Erin M.; Der, Joshua P.; Pittermann, Jarmila; Burge, Dylan O.; Pokorny, Lisa; Larsson, Anders; Chen, Tao; Weststrand, Stina; Thomas, Philip; Carpenter, Eric; Zhang, Yong; Tian, Zhijian; Chen, Li; Yan, Zhixiang; Zhu, Ying; Sun, Xiao; Wang, Jun; Stevenson, Dennis W.; Crandall-Stotler, Barbara J.; Shaw, A. Jonathan; Deyholos, Michael K.; Soltis, Douglas E.; Graham, Sean W.; Windham, Michael D.; Langdale, Jane A.; Wong, Gane Ka-Shu; Mathews, Sarah; Pryer, Kathleen M.

2014-01-01

Ferns are well known for their shade-dwelling habits. Their ability to thrive under low-light conditions has been linked to the evolution of a novel chimeric photoreceptor—neochrome—that fuses red-sensing phytochrome and blue-sensing phototropin modules into a single gene, thereby optimizing phototropic responses. Despite being implicated in facilitating the diversification of modern ferns, the origin of neochrome has remained a mystery. We present evidence for neochrome in hornworts (a bryophyte lineage) and demonstrate that ferns acquired neochrome from hornworts via horizontal gene transfer (HGT). Fern neochromes are nested within hornwort neochromes in our large-scale phylogenetic reconstructions of phototropin and phytochrome gene families. Divergence date estimates further support the HGT hypothesis, with fern and hornwort neochromes diverging 179 Mya, long after the split between the two plant lineages (at least 400 Mya). By analyzing the draft genome of the hornwort Anthoceros punctatus, we also discovered a previously unidentified phototropin gene that likely represents the ancestral lineage of the neochrome phototropin module. Thus, a neochrome originating in hornworts was transferred horizontally to ferns, where it may have played a significant role in the diversification of modern ferns. PMID:24733898

Symptoms of Fern Distortion Syndrome Resulting from Inoculation with Opportunistic Endophytic Fluorescent Pseudomonas spp.

PubMed Central

Kloepper, Joseph W.; McInroy, John A.; Liu, Ke; Hu, Chia-Hui

2013-01-01

Background Fern Distortion Syndrome (FDS) is a serious disease of Leatherleaf fern (Rumohra adiantiformis). The main symptom of FDS is distortion of fronds, making them unmarketable. Additional symptoms include stunting, irregular sporulation, decreased rhizome diameter, and internal discoloration of rhizomes. We previously reported an association of symptoms with increased endophytic rhizome populations of fluorescent pseudomonads (FPs). The aim of the current study was to determine if FPs from ferns in Costa Rica with typical FDS symptoms would recreate symptoms of FDS. Methodology and Findings Greenhouse tests were conducted over a 29-month period. Micro-propagated ferns derived from tissue culture were first grown one year to produce rhizomes. Then, using an 8×9 randomized complete block experimental design, 8 replicate rhizomes were inoculated by dipping into 9 different treatments before planting. Treatments included water without bacteria (control), and four different groups of FPs, each at a two concentrations. The four groups of FPs included one group from healthy ferns without symptoms (another control treatment), two groups isolated from inside rhizomes of symptomatic ferns, and one group isolated from inside roots of symptomatic ferns. Symptoms were assessed 12 and 17 months later, and populations of FPs inside newly formed rhizomes were determined after 17 months. Results showed that inoculation with mixtures of FPs from ferns with FDS symptoms, but not from healthy ferns, recreated the primary symptom of frond deformities and also the secondary symptoms of irregular sporulation, decreased rhizome diameter, and internal discoloration of rhizomes. Conclusions These results suggest a model of causation of FDS in which symptoms result from latent infections by multiple species of opportunistic endophytic bacteria containing virulence genes that are expressed when populations inside the plant reach a minimum level. PMID:23516499

rbcL and matK earn two thumbs up as the core DNA barcode for ferns.

PubMed

Li, Fay-Wei; Kuo, Li-Yaung; Rothfels, Carl J; Ebihara, Atsushi; Chiou, Wen-Liang; Windham, Michael D; Pryer, Kathleen M

2011-01-01

DNA barcoding will revolutionize our understanding of fern ecology, most especially because the accurate identification of the independent but cryptic gametophyte phase of the fern's life history--an endeavor previously impossible--will finally be feasible. In this study, we assess the discriminatory power of the core plant DNA barcode (rbcL and matK), as well as alternatively proposed fern barcodes (trnH-psbA and trnL-F), across all major fern lineages. We also present plastid barcode data for two genera in the hyperdiverse polypod clade--Deparia (Woodsiaceae) and the Cheilanthes marginata group (currently being segregated as a new genus of Pteridaceae)--to further evaluate the resolving power of these loci. Our results clearly demonstrate the value of matK data, previously unavailable in ferns because of difficulties in amplification due to a major rearrangement of the plastid genome. With its high sequence variation, matK complements rbcL to provide a two-locus barcode with strong resolving power. With sequence variation comparable to matK, trnL-F appears to be a suitable alternative barcode region in ferns, and perhaps should be added to the core barcode region if universal primer development for matK fails. In contrast, trnH-psbA shows dramatically reduced sequence variation for the majority of ferns. This is likely due to the translocation of this segment of the plastid genome into the inverted repeat regions, which are known to have a highly constrained substitution rate. Our study provides the first endorsement of the two-locus barcode (rbcL+matK) in ferns, and favors trnL-F over trnH-psbA as a potential back-up locus. Future work should focus on gathering more fern matK sequence data to facilitate universal primer development.

Tree fern trunks facilitate seedling regeneration in a productive lowland temperate rain forest.

PubMed

Gaxiola, Aurora; Burrows, Larry E; Coomes, David A

2008-03-01

Seedling regeneration on forest floors is often impaired by competition with established plants. In some lowland temperate rain forests, tree fern trunks provide safe sites on which tree species establish, and grow large enough to take root in the ground and persist. Here we explore the competitive and facilitative effects of two tree fern species, Cyathea smithii and Dicksonia squarrosa, on the epiphytic regeneration of tree species in nutrient-rich alluvial forests in New Zealand. The difficulties that seedlings have in establishing on vertical tree fern trunks were indicated by the following observations. First, seedling abundance was greatest on the oldest sections of tree fern trunks, near the base, suggesting that trunks gradually recruited more and more seedlings over time, but many sections of trunk were devoid of seedlings, indicating the difficulty of establishment on a vertical surface. Second, most seedlings were from small-seeded species, presumably because smaller seeds can easily lodge on tree fern trunks. Deer browsing damage was observed on 73% of epiphytic seedlings growing within 2 m of the ground, whereas few seedlings above that height were browsed. This suggests that tree ferns provide refugia from introduced deer, and may slow the decline in population size of deer-preferred species. We reasoned that tree ferns would compete with epiphytic seedlings for light, because below the tree fern canopy photosynthetically active radiation (PAR) was about 1% of above-canopy PAR. Frond removal almost tripled %PAR on the forest floor, leading to a significant increase in the height growth rate (HGR) of seedlings planted on the forest floor, but having no effects on the HGRs of epiphytic seedlings. Our study shows evidence of direct facilitative interactions by tree ferns during seedling establishment in plant communities associated with nutrient-rich soils.

The first fossil of a bolbitidoid fern belongs to the early-divergent lineages of Elaphoglossum (Dryopteridaceae).

PubMed

Lóriga, Josmaily; Schmidt, Alexander R; Moran, Robbin C; Feldberg, Kathrin; Schneider, Harald; Heinrichs, Jochen

2014-09-01

• Closing gaps in the fossil record and elucidating phylogenetic relationships of mostly incomplete fossils are major challenges in the reconstruction of the diversification of fern lineages through time. The cosmopolitan family Dryopteridaceae represents one of the most species-rich families of leptosporangiate ferns, yet its fossil record is sparse and poorly understood. Here, we describe a fern inclusion in Miocene Dominican amber and investigate its relationships to extant Dryopteridaceae.• The morphology of the fossil was compared with descriptions of extant ferns, resulting in it being tentatively assigned to the bolbitidoid fern genus Elaphoglossum. This assignment was confirmed by reconstructing the evolution of the morphological characters preserved in the inclusion on a molecular phylogeny of 158 extant bolbitidoid ferns. To assess the morphology-based assignment of the fossil to Elaphoglossum, we examined DNA-calibrated divergence time estimates against the age of the amber deposits from which it came.• The fossil belongs to Elaphoglossum and is the first of a bolbitidoid fern. Its assignment to a particular section of Elaphoglossum could not be determined; however, sects. Lepidoglossa, Polytrichia, and Setosa can be discounted because the fossil lacks subulate scales or scales with acicular marginal hairs. Thus, the fossil might belong to either sects. Amygdalifolia, Wrightiana, Elaphoglossum, or Squamipedia or to an extinct lineage.• The discovery of a Miocene Elaphoglossum fossil provides remarkable support to current molecular clock-based estimates of the diversification of these ferns. © 2014 Botanical Society of America, Inc.

Is there foul play in the leaf pocket? The metagenome of floating fern Azolla reveals endophytes that do not fix N2 but may denitrify.

PubMed

Dijkhuizen, Laura W; Brouwer, Paul; Bolhuis, Henk; Reichart, Gert-Jan; Koppers, Nils; Huettel, Bruno; Bolger, Anthony M; Li, Fay-Wei; Cheng, Shifeng; Liu, Xin; Wong, Gane Ka-Shu; Pryer, Kathleen; Weber, Andreas; Bräutigam, Andrea; Schluepmann, Henriette

2018-01-01

Dinitrogen fixation by Nostoc azollae residing in specialized leaf pockets supports prolific growth of the floating fern Azolla filiculoides. To evaluate contributions by further microorganisms, the A. filiculoides microbiome and nitrogen metabolism in bacteria persistently associated with Azolla ferns were characterized. A metagenomic approach was taken complemented by detection of N 2 O released and nitrogen isotope determinations of fern biomass. Ribosomal RNA genes in sequenced DNA of natural ferns, their enriched leaf pockets and water filtrate from the surrounding ditch established that bacteria of A. filiculoides differed entirely from surrounding water and revealed species of the order Rhizobiales. Analyses of seven cultivated Azolla species confirmed persistent association with Rhizobiales. Two distinct nearly full-length Rhizobiales genomes were identified in leaf-pocket-enriched samples from ditch grown A. filiculoides. Their annotation revealed genes for denitrification but not N 2 -fixation. 15 N 2 incorporation was active in ferns with N. azollae but not in ferns without. N 2 O was not detectably released from surface-sterilized ferns with the Rhizobiales. N 2 -fixing N. azollae, we conclude, dominated the microbiome of Azolla ferns. The persistent but less abundant heterotrophic Rhizobiales bacteria possibly contributed to lowering O 2 levels in leaf pockets but did not release detectable amounts of the strong greenhouse gas N 2 O. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

A molecular phylogeny of scaly tree ferns (Cyatheaceae).

PubMed

Korall, Petra; Conant, David S; Metzgar, Jordan S; Schneider, Harald; Pryer, Kathleen M

2007-05-01

Tree ferns recently were identified as the closest sister group to the hyperdiverse clade of ferns, the polypods. Although most of the 600 species of tree ferns are arborescent, the group encompasses a wide range of morphological variability, from diminutive members to the giant scaly tree ferns, Cyatheaceae. This well-known family comprises most of the tree fern diversity (∼500 species) and is widespread in tropical, subtropical, and south temperate regions of the world. Here we investigate the phylogenetic relationships of scaly tree ferns based on DNA sequence data from five plastid regions (rbcL, rbcL-accD IGS, rbcL-atpB IGS, trnG-trnR, and trnL-trnF). A basal dichotomy resolves Sphaeropteris as sister to all other taxa and scale features support these two clades: Sphaeropteris has conform scales, whereas all other taxa have marginate scales. The marginate-scaled clade consists of a basal trichotomy, with the three groups here termed (1) Cyathea (including Cnemidaria, Hymenophyllopsis, Trichipteris), (2) Alsophila sensu stricto, and (3) Gymnosphaera (previously recognized as a section within Alsophila) + A. capensis. Scaly tree ferns display a wide range of indusial structures, and although indusium shape is homoplastic it does contain useful phylogenetic information that supports some of the larger clades recognised.

Arsenic accumulation by two brake ferns growing on an arsenic mine and their potential in phytoremediation.

PubMed

Wei, Chao-Yang; Chen, Tong-Bin

2006-05-01

In an area near an arsenic mine in Hunan Province of south China, soils were often found with elevated arsenic levels. A field survey was conducted to determine arsenic accumulation in 8 Cretan brake ferns (Pteris cretica) and 16 Chinese brake ferns (Pteris vittata) growing on these soils. Three factors were evaluated: arsenic concentration in above ground parts (fronds), arsenic bioaccumulation factor (BF; ratio of arsenic in fronds to soil) and arsenic translocation factor (TF; ratio of arsenic in fronds to roots). Arsenic concentrations in the fronds of Chinese brake fern were 3-704 mg kg-1, the BFs were 0.06-7.43 and the TFs were 0.17-3.98, while those in Cretan brake fern were 149-694 mg kg-1, 1.34-6.62 and 1.00-2.61, respectively. Our survey showed that both ferns were capable of arsenic accumulation under field conditions. With most of the arsenic being accumulated in the fronds, these ferns have potential for use in phytoremediation of arsenic contaminated soils.

Trends and concepts in fern classification.

PubMed

Christenhusz, Maarten J M; Chase, Mark W

2014-03-01

Throughout the history of fern classification, familial and generic concepts have been highly labile. Many classifications and evolutionary schemes have been proposed during the last two centuries, reflecting different interpretations of the available evidence. Knowledge of fern structure and life histories has increased through time, providing more evidence on which to base ideas of possible relationships, and classification has changed accordingly. This paper reviews previous classifications of ferns and presents ideas on how to achieve a more stable consensus. An historical overview is provided from the first to the most recent fern classifications, from which conclusions are drawn on past changes and future trends. The problematic concept of family in ferns is discussed, with a particular focus on how this has changed over time. The history of molecular studies and the most recent findings are also presented. Fern classification generally shows a trend from highly artificial, based on an interpretation of a few extrinsic characters, via natural classifications derived from a multitude of intrinsic characters, towards more evolutionary circumscriptions of groups that do not in general align well with the distribution of these previously used characters. It also shows a progression from a few broad family concepts to systems that recognized many more narrowly and highly controversially circumscribed families; currently, the number of families recognized is stabilizing somewhere between these extremes. Placement of many genera was uncertain until the arrival of molecular phylogenetics, which has rapidly been improving our understanding of fern relationships. As a collective category, the so-called 'fern allies' (e.g. Lycopodiales, Psilotaceae, Equisetaceae) were unsurprisingly found to be polyphyletic, and the term should be abandoned. Lycopodiaceae, Selaginellaceae and Isoëtaceae form a clade (the lycopods) that is sister to all other vascular plants, whereas the whisk ferns (Psilotaceae), often included in the lycopods or believed to be associated with the first vascular plants, are sister to Ophioglossaceae and thus belong to the fern clade. The horsetails (Equisetaceae) are also members of the fern clade (sometimes inappropriately called 'monilophytes'), but, within that clade, their placement is still uncertain. Leptosporangiate ferns are better understood, although deep relationships within this group are still unresolved. Earlier, almost all leptosporangiate ferns were placed in a single family (Polypodiaceae or Dennstaedtiaceae), but these families have been redefined to narrower more natural entities. Concluding this paper, a classification is presented based on our current understanding of relationships of fern and lycopod clades. Major changes in our understanding of these families are highlighted, illustrating issues of classification in relation to convergent evolution and false homologies. Problems with the current classification and groups that still need study are pointed out. A summary phylogenetic tree is also presented. A new classification in which Aspleniaceae, Cyatheaceae, Polypodiaceae and Schizaeaceae are expanded in comparison with the most recent classifications is presented, which is a modification of those proposed by Smith et al. (2006, 2008) and Christenhusz et al. (2011). These classifications are now finding a wider acceptance and use, and even though a few amendments are made based on recently published results from molecular analyses, we have aimed for a stable family and generic classification of ferns.

Control of hay-scented and New York ferns with Oust Xp® herbicide: Revisiting rate and timing required in mixed oak and northern hardwood stands

Treesearch

Todd E. Ristau

2017-01-01

Dense rhizomatous fern layers compete with desirable tree seedlings for light, which suppresses development and even kills seedlings. Sulfometuron methyl (Oust XP®) herbicide can be safely and effectively used to control ferns. Previous research showed that depending on application timing, as little as 2 ounces of Oust XP per acre controlled ferns while hardwood tree...

Towards resolving the complete fern tree of life.

PubMed

Lehtonen, Samuli

2011-01-01

In the past two decades, molecular systematic studies have revolutionized our understanding of the evolutionary history of ferns. The availability of large molecular data sets together with efficient computer algorithms, now enables us to reconstruct evolutionary histories with previously unseen completeness. Here, the most comprehensive fern phylogeny to date, representing over one-fifth of the extant global fern diversity, is inferred based on four plastid genes. Parsimony and maximum-likelihood analyses provided a mostly congruent results and in general supported the prevailing view on the higher-level fern systematics. At a deep phylogenetic level, the position of horsetails depended on the optimality criteria chosen, with horsetails positioned as the sister group either of Marattiopsida-Polypodiopsida clade or of the Polypodiopsida. The analyses demonstrate the power of using a 'supermatrix' approach to resolve large-scale phylogenies and reveal questionable taxonomies. These results provide a valuable background for future research on fern systematics, ecology, biogeography and other evolutionary studies.

Fern Stomatal Responses to ABA and CO2 Depend on Species and Growth Conditions.

PubMed

Hõrak, Hanna; Kollist, Hannes; Merilo, Ebe

2017-06-01

Changing atmospheric CO 2 levels, climate, and air humidity affect plant gas exchange that is controlled by stomata, small pores on plant leaves and stems formed by guard cells. Evolution has shaped the morphology and regulatory mechanisms governing stomatal movements to correspond to the needs of various land plant groups over the past 400 million years. Stomata close in response to the plant hormone abscisic acid (ABA), elevated CO 2 concentration, and reduced air humidity. Whether the active regulatory mechanisms that control stomatal closure in response to these stimuli are present already in mosses, the oldest plant group with stomata, or were acquired more recently in angiosperms remains controversial. It has been suggested that the stomata of the basal vascular plants, such as ferns and lycophytes, close solely hydropassively. On the other hand, active stomatal closure in response to ABA and CO 2 was found in several moss, lycophyte, and fern species. Here, we show that the stomata of two temperate fern species respond to ABA and CO 2 and that an active mechanism of stomatal regulation in response to reduced air humidity is present in some ferns. Importantly, fern stomatal responses depend on growth conditions. The data indicate that the stomatal behavior of ferns is more complex than anticipated before, and active stomatal regulation is present in some ferns and has possibly been lost in others. Further analysis that takes into account fern species, life history, evolutionary age, and growth conditions is required to gain insight into the evolution of land plant stomatal responses. © 2017 American Society of Plant Biologists. All Rights Reserved.

Transcriptome sequencing reveals genome-wide variation in molecular evolutionary rate among ferns.

PubMed

Grusz, Amanda L; Rothfels, Carl J; Schuettpelz, Eric

2016-08-30

Transcriptomics in non-model plant systems has recently reached a point where the examination of nuclear genome-wide patterns in understudied groups is an achievable reality. This progress is especially notable in evolutionary studies of ferns, for which molecular resources to date have been derived primarily from the plastid genome. Here, we utilize transcriptome data in the first genome-wide comparative study of molecular evolutionary rate in ferns. We focus on the ecologically diverse family Pteridaceae, which comprises about 10 % of fern diversity and includes the enigmatic vittarioid ferns-an epiphytic, tropical lineage known for dramatically reduced morphologies and radically elongated phylogenetic branch lengths. Using expressed sequence data for 2091 loci, we perform pairwise comparisons of molecular evolutionary rate among 12 species spanning the three largest clades in the family and ask whether previously documented heterogeneity in plastid substitution rates is reflected in their nuclear genomes. We then inquire whether variation in evolutionary rate is being shaped by genes belonging to specific functional categories and test for differential patterns of selection. We find significant, genome-wide differences in evolutionary rate for vittarioid ferns relative to all other lineages within the Pteridaceae, but we recover few significant correlations between faster/slower vittarioid loci and known functional gene categories. We demonstrate that the faster rates characteristic of the vittarioid ferns are likely not driven by positive selection, nor are they unique to any particular type of nucleotide substitution. Our results reinforce recently reviewed mechanisms hypothesized to shape molecular evolutionary rates in vittarioid ferns and provide novel insight into substitution rate variation both within and among fern nuclear genomes.

Fern Stomatal Responses to ABA and CO2 Depend on Species and Growth Conditions1[OPEN

PubMed Central

2017-01-01

Changing atmospheric CO2 levels, climate, and air humidity affect plant gas exchange that is controlled by stomata, small pores on plant leaves and stems formed by guard cells. Evolution has shaped the morphology and regulatory mechanisms governing stomatal movements to correspond to the needs of various land plant groups over the past 400 million years. Stomata close in response to the plant hormone abscisic acid (ABA), elevated CO2 concentration, and reduced air humidity. Whether the active regulatory mechanisms that control stomatal closure in response to these stimuli are present already in mosses, the oldest plant group with stomata, or were acquired more recently in angiosperms remains controversial. It has been suggested that the stomata of the basal vascular plants, such as ferns and lycophytes, close solely hydropassively. On the other hand, active stomatal closure in response to ABA and CO2 was found in several moss, lycophyte, and fern species. Here, we show that the stomata of two temperate fern species respond to ABA and CO2 and that an active mechanism of stomatal regulation in response to reduced air humidity is present in some ferns. Importantly, fern stomatal responses depend on growth conditions. The data indicate that the stomatal behavior of ferns is more complex than anticipated before, and active stomatal regulation is present in some ferns and has possibly been lost in others. Further analysis that takes into account fern species, life history, evolutionary age, and growth conditions is required to gain insight into the evolution of land plant stomatal responses. PMID:28351911

Germination fitness of two temperate epiphytic ferns shifts under increasing temperatures and forest fragmentation.

PubMed

Gabriel Y Galán, Jose María; Murciano, Antonio; Sirvent, Laure; Sánchez, Abel; Watkins, James E

2018-01-01

Ferns are an important component of ecosystems around the world. Studies of the impacts that global changes may have on ferns are scarce, yet emerging studies indicate that some species may be particularly sensitive to climate change. The lack of research in this subject is much more aggravated in the case of epiphytes, and especially those that live under temperate climates. A mathematical model was developed for two temperate epiphytic ferns in order to predict potential impacts on spore germination kinetics, in response to different scenarios of global change, coming from increasing temperature and forest fragmentation. Our results show that an increasing temperature will have a negative impact over the populations of these temperate epiphytic ferns. Under unfragmented forests the germination percentage was comparatively less influenced than in fragmented patches. This study highlight that, in the long term, populations of the studied epiphytic temperate ferns may decline due to climate change. Overall, epiphytic fern communities will suffer changes in diversity, richness and dominance. Our study draws attention to the role of ferns in epiphytic communities of temperate forests, emphasizing the importance of considering these plants in any conservation strategy, specifically forest conservation. From a methodological point of view, the model we propose could be easily used to dynamically monitor the status of ecosystems, allowing the quick prediction of possible future scenarios, which is a crucial issue in biodiversity conservation decision-making.

Physiological mechanisms drive differing foliar calcium content in ferns and angiosperms.

PubMed

Funk, Jennifer L; Amatangelo, Kathryn L

2013-09-01

Recent evidence points to ferns containing significantly lower contents of foliar calcium and other cations than angiosperms. This is especially true of more ancient 'non-polypod' fern lineages, which predate the diversification of angiosperms. Calcium is an important plant nutrient, the lack of which can potentially slow plant growth and litter decomposition, and alter soil invertebrate communities. The physiological mechanisms limiting foliar calcium (Ca) content in ferns are unknown. While there is a lot we do not know about Ca uptake and transport in plants, three physiological processes are likely to be important. We measured transpiration rate, cation exchange capacity, and leaching loss to determine which process most strongly regulates foliar Ca content in a range of fern and co-occurring understory angiosperm species from a montane Hawaiian rainforest. We found higher instantaneous and lifetime (corrected for leaf lifespan) transpiration rates in angiosperms relative to ferns. Ferns preferentially incorporated Ca into leaves relative to strontium, which suggests that root or stem cation exchange capacity differs between ferns and angiosperms, potentially affecting calcium transport in plants. There were no differences in foliar Ca leaching loss between groups. Among the physiological mechanisms measured, foliar Ca was most strongly correlated with leaf-level transpiration rate and leaf lifespan. This suggests that inter-specific differences in a leaf's lifetime transpiration may play a significant role in determining plant nutrition.

Use of rbcL and trnL-F as a Two-Locus DNA Barcode for Identification of NW-European Ferns: An Ecological Perspective

PubMed Central

de Groot, G. Arjen; During, Heinjo J.; Maas, Jan W.; Schneider, Harald; Vogel, Johannes C.; Erkens, Roy H. J.

2011-01-01

Although consensus has now been reached on a general two-locus DNA barcode for land plants, the selected combination of markers (rbcL + matK) is not applicable for ferns at the moment. Yet especially for ferns, DNA barcoding is potentially of great value since fern gametophytes—while playing an essential role in fern colonization and reproduction—generally lack the morphological complexity for morphology-based identification and have therefore been underappreciated in ecological studies. We evaluated the potential of a combination of rbcL with a noncoding plastid marker, trnL-F, to obtain DNA-identifications for fern species. A regional approach was adopted, by creating a reference database of trusted rbcL and trnL-F sequences for the wild-occurring homosporous ferns of NW-Europe. A combination of parsimony analyses and distance-based analyses was performed to evaluate the discriminatory power of the two-region barcode. DNA was successfully extracted from 86 tiny fern gametophytes and was used as a test case for the performance of DNA-based identification. Primer universality proved high for both markers. Based on the combined rbcL + trnL-F dataset, all genera as well as all species with non-equal chloroplast genomes formed their own well supported monophyletic clade, indicating a high discriminatory power. Interspecific distances were larger than intraspecific distances for all tested taxa. Identification tests on gametophytes showed a comparable result. All test samples could be identified to genus level, species identification was well possible unless they belonged to a pair of Dryopteris species with completely identical chloroplast genomes. Our results suggest a high potential of the combined use of rbcL and trnL-F as a two-locus cpDNA barcode for identification of fern species. A regional approach may be preferred for ecological tests. We here offer such a ready-to-use barcoding approach for ferns, which opens the way for answering a whole range of questions previously unaddressed in fern gametophyte ecology. PMID:21298108

Trends and concepts in fern classification

PubMed Central

Christenhusz, Maarten J. M.; Chase, Mark W.

2014-01-01

Background and Aims Throughout the history of fern classification, familial and generic concepts have been highly labile. Many classifications and evolutionary schemes have been proposed during the last two centuries, reflecting different interpretations of the available evidence. Knowledge of fern structure and life histories has increased through time, providing more evidence on which to base ideas of possible relationships, and classification has changed accordingly. This paper reviews previous classifications of ferns and presents ideas on how to achieve a more stable consensus. Scope An historical overview is provided from the first to the most recent fern classifications, from which conclusions are drawn on past changes and future trends. The problematic concept of family in ferns is discussed, with a particular focus on how this has changed over time. The history of molecular studies and the most recent findings are also presented. Key Results Fern classification generally shows a trend from highly artificial, based on an interpretation of a few extrinsic characters, via natural classifications derived from a multitude of intrinsic characters, towards more evolutionary circumscriptions of groups that do not in general align well with the distribution of these previously used characters. It also shows a progression from a few broad family concepts to systems that recognized many more narrowly and highly controversially circumscribed families; currently, the number of families recognized is stabilizing somewhere between these extremes. Placement of many genera was uncertain until the arrival of molecular phylogenetics, which has rapidly been improving our understanding of fern relationships. As a collective category, the so-called ‘fern allies’ (e.g. Lycopodiales, Psilotaceae, Equisetaceae) were unsurprisingly found to be polyphyletic, and the term should be abandoned. Lycopodiaceae, Selaginellaceae and Isoëtaceae form a clade (the lycopods) that is sister to all other vascular plants, whereas the whisk ferns (Psilotaceae), often included in the lycopods or believed to be associated with the first vascular plants, are sister to Ophioglossaceae and thus belong to the fern clade. The horsetails (Equisetaceae) are also members of the fern clade (sometimes inappropriately called ‘monilophytes’), but, within that clade, their placement is still uncertain. Leptosporangiate ferns are better understood, although deep relationships within this group are still unresolved. Earlier, almost all leptosporangiate ferns were placed in a single family (Polypodiaceae or Dennstaedtiaceae), but these families have been redefined to narrower more natural entities. Conclusions Concluding this paper, a classification is presented based on our current understanding of relationships of fern and lycopod clades. Major changes in our understanding of these families are highlighted, illustrating issues of classification in relation to convergent evolution and false homologies. Problems with the current classification and groups that still need study are pointed out. A summary phylogenetic tree is also presented. A new classification in which Aspleniaceae, Cyatheaceae, Polypodiaceae and Schizaeaceae are expanded in comparison with the most recent classifications is presented, which is a modification of those proposed by Smith et al. (2006, 2008) and Christenhusz et al. (2011). These classifications are now finding a wider acceptance and use, and even though a few amendments are made based on recently published results from molecular analyses, we have aimed for a stable family and generic classification of ferns. PMID:24532607

rbcL and matK Earn Two Thumbs Up as the Core DNA Barcode for Ferns

PubMed Central

Li, Fay-Wei; Kuo, Li-Yaung; Rothfels, Carl J.; Ebihara, Atsushi; Chiou, Wen-Liang; Windham, Michael D.; Pryer, Kathleen M.

2011-01-01

Background DNA barcoding will revolutionize our understanding of fern ecology, most especially because the accurate identification of the independent but cryptic gametophyte phase of the fern's life history—an endeavor previously impossible—will finally be feasible. In this study, we assess the discriminatory power of the core plant DNA barcode (rbcL and matK), as well as alternatively proposed fern barcodes (trnH-psbA and trnL-F), across all major fern lineages. We also present plastid barcode data for two genera in the hyperdiverse polypod clade—Deparia (Woodsiaceae) and the Cheilanthes marginata group (currently being segregated as a new genus of Pteridaceae)—to further evaluate the resolving power of these loci. Principal Findings Our results clearly demonstrate the value of matK data, previously unavailable in ferns because of difficulties in amplification due to a major rearrangement of the plastid genome. With its high sequence variation, matK complements rbcL to provide a two-locus barcode with strong resolving power. With sequence variation comparable to matK, trnL-F appears to be a suitable alternative barcode region in ferns, and perhaps should be added to the core barcode region if universal primer development for matK fails. In contrast, trnH-psbA shows dramatically reduced sequence variation for the majority of ferns. This is likely due to the translocation of this segment of the plastid genome into the inverted repeat regions, which are known to have a highly constrained substitution rate. Conclusions Our study provides the first endorsement of the two-locus barcode (rbcL+matK) in ferns, and favors trnL-F over trnH-psbA as a potential back-up locus. Future work should focus on gathering more fern matK sequence data to facilitate universal primer development. PMID:22028918

Genome size evolution in Ontario ferns (Polypodiidae): evolutionary correlations with cell size, spore size, and habitat type and an absence of genome downsizing.

PubMed

Henry, Thomas A; Bainard, Jillian D; Newmaster, Steven G

2014-10-01

Genome size is known to correlate with a number of traits in angiosperms, but less is known about the phenotypic correlates of genome size in ferns. We explored genome size variation in relation to a suite of morphological and ecological traits in ferns. Thirty-six fern taxa were collected from wild populations in Ontario, Canada. 2C DNA content was measured using flow cytometry. We tested for genome downsizing following polyploidy using a phylogenetic comparative analysis to explore the correlation between 1Cx DNA content and ploidy. There was no compelling evidence for the occurrence of widespread genome downsizing during the evolution of Ontario ferns. The relationship between genome size and 11 morphological and ecological traits was explored using a phylogenetic principal component regression analysis. Genome size was found to be significantly associated with cell size, spore size, spore type, and habitat type. These results are timely as past and recent studies have found conflicting support for the association between ploidy/genome size and spore size in fern polyploid complexes; this study represents the first comparative analysis of the trend across a broad taxonomic group of ferns.

Metabolic Adaptation, a Specialized Leaf Organ Structure and Vascular Responses to Diurnal N2 Fixation by Nostoc azollae Sustain the Astonishing Productivity of Azolla Ferns without Nitrogen Fertilizer.

PubMed

Brouwer, Paul; Bräutigam, Andrea; Buijs, Valerie A; Tazelaar, Anne O E; van der Werf, Adrie; Schlüter, Urte; Reichart, Gert-Jan; Bolger, Anthony; Usadel, Björn; Weber, Andreas P M; Schluepmann, Henriette

2017-01-01

Sustainable agriculture demands reduced input of man-made nitrogen (N) fertilizer, yet N 2 fixation limits the productivity of crops with heterotrophic diazotrophic bacterial symbionts. We investigated floating ferns from the genus Azolla that host phototrophic diazotrophic Nostoc azollae in leaf pockets and belong to the fastest growing plants. Experimental production reported here demonstrated N-fertilizer independent production of nitrogen-rich biomass with an annual yield potential per ha of 1200 kg -1 N fixed and 35 t dry biomass. 15 N 2 fixation peaked at noon, reaching 0.4 mg N g -1 dry weight h -1 . Azolla ferns therefore merit consideration as protein crops in spite of the fact that little is known about the fern's physiology to enable domestication. To gain an understanding of their nitrogen physiology, analyses of fern diel transcript profiles under differing nitrogen fertilizer regimes were combined with microscopic observations. Results established that the ferns adapted to the phototrophic N 2 -fixing symbionts N. azollae by (1) adjusting metabolically to nightly absence of N supply using responses ancestral to ferns and seed plants; (2) developing a specialized xylem-rich vasculature surrounding the leaf-pocket organ; (3) responding to N-supply by controlling transcripts of genes mediating nutrient transport, allocation and vasculature development. Unlike other non-seed plants, the Azolla fern clock is shown to contain both the morning and evening loops; the evening loop is known to control rhythmic gene expression in the vasculature of seed plants and therefore may have evolved along with the vasculature in the ancestor of ferns and seed plants.

An ant-plant by-product mutualism is robust to selective logging of rain forest and conversion to oil palm plantation.

PubMed

Fayle, Tom M; Edwards, David P; Foster, William A; Yusah, Kalsum M; Turner, Edgar C

2015-06-01

Anthropogenic disturbance and the spread of non-native species disrupt natural communities, but also create novel interactions between species. By-product mutualisms, in which benefits accrue as side effects of partner behaviour or morphology, are often non-specific and hence may persist in novel ecosystems. We tested this hypothesis for a two-way by-product mutualism between epiphytic ferns and their ant inhabitants in the Bornean rain forest, in which ants gain housing in root-masses while ferns gain protection from herbivores. Specifically, we assessed how the specificity (overlap between fern and ground-dwelling ants) and the benefits of this interaction are altered by selective logging and conversion to an oil palm plantation habitat. We found that despite the high turnover of ant species, ant protection against herbivores persisted in modified habitats. However, in ferns growing in the oil palm plantation, ant occupancy, abundance and species richness declined, potentially due to the harsher microclimate. The specificity of the fern-ant interactions was also lower in the oil palm plantation habitat than in the forest habitats. We found no correlations between colony size and fern size in modified habitats, and hence no evidence for partner fidelity feedbacks, in which ants are incentivised to protect fern hosts. Per species, non-native ant species in the oil palm plantation habitat (18 % of occurrences) were as important as native ones in terms of fern protection and contributed to an increase in ant abundance and species richness with fern size. We conclude that this by-product mutualism persists in logged forest and oil palm plantation habitats, with no detectable shift in partner benefits. Such persistence of generalist interactions in novel ecosystems may be important for driving ecosystem functioning.

Exploring the Impact of Food on the Gut Ecosystem Based on the Combination of Machine Learning and Network Visualization.

PubMed

Shima, Hideaki; Masuda, Shizuka; Date, Yasuhiro; Shino, Amiu; Tsuboi, Yuuri; Kajikawa, Mizuho; Inoue, Yoshihiro; Kanamoto, Taisei; Kikuchi, Jun

2017-12-01

Prebiotics and probiotics strongly impact the gut ecosystem by changing the composition and/or metabolism of the microbiota to improve the health of the host. However, the composition of the microbiota constantly changes due to the intake of daily diet. This shift in the microbiota composition has a considerable impact; however, non-pre/probiotic foods that have a low impact are ignored because of the lack of a highly sensitive evaluation method. We performed comprehensive acquisition of data using existing measurements (nuclear magnetic resonance, next-generation DNA sequencing, and inductively coupled plasma-optical emission spectroscopy) and analyses based on a combination of machine learning and network visualization, which extracted important factors by the Random Forest approach, and applied these factors to a network module. We used two pteridophytes, Pteridium aquilinum and Matteuccia struthiopteris , for the representative daily diet. This novel analytical method could detect the impact of a small but significant shift associated with Matteuccia struthiopteris but not Pteridium aquilinum intake, using the functional network module. In this study, we proposed a novel method that is useful to explore a new valuable food to improve the health of the host as pre/probiotics.

Further Experiments with Ferns in Culture: Regeneration.

ERIC Educational Resources Information Center

Sheffield, Elizabeth; Attree, Stephen M.

1983-01-01

Ferns in culture provide versatile and easily manipulated material for a wide variety of experiments and observations. Information is provided that supplements earlier reports of the vast experimental potential of these cryptogams and outlines laboratory exercises which reveal the regenerative behavior of fern tissue. (JN)

Soral crypsis: protective mimicry of a coccid on an Indian fern.

PubMed

Patra, Biplab; Bera, Subir; Hickey, R James

2008-06-01

Herbivory with crypsis is not well documented in ferns. The present record of cryptic coloration of coccid Saissetia filicum Boisduval (Homoptera: Coccidae) to the sori of a fern species Asplenium nidus L. (Aspleniaceae) is unique. Predatory beetles (Jauravia sp., Coleoptera: Coccinellidae) that feed on the coccids, are suggested to be selective pressure for the development of the present homopteran soral crypsis. A higher rate of effective predation is noticed in the vegetative leaves than the fertile leaves. Aggressive ants were found harvesting honeydew secretions from the coccids and defending the trophobionts as well as the host fern from their natural enemies. In addition, a possible three-way mutualistic relationship among the coccids, its host fern and the tending ant is suggested. Differential numbers of coccids on vegetative and fertile leaves is correlated with their phenol content and degree of predation by beetles. Such coloration mimicry by the coccids may enable them to obtain the necessary blend of sorus of the host fern needed to evade beetle detection and attack.

Two New Fern Chloroplasts and Decelerated Evolution Linked to the Long Generation Time in Tree Ferns

PubMed Central

Zhong, Bojian; Fong, Richard; Collins, Lesley J.; McLenachan, Patricia A.; Penny, David

2014-01-01

We report the chloroplast genomes of a tree fern (Dicksonia squarrosa) and a “fern ally” (Tmesipteris elongata), and show that the phylogeny of early land plants is basically as expected, and the estimates of divergence time are largely unaffected after removing the fastest evolving sites. The tree fern shows the major reduction in the rate of evolution, and there has been a major slowdown in the rate of mutation in both families of tree ferns. We suggest that this is related to a generation time effect; if there is a long time period between generations, then this is probably incompatible with a high mutation rate because otherwise nearly every propagule would probably have several lethal mutations. This effect will be especially strong in organisms that have large numbers of cell divisions between generations. This shows the necessity of going beyond phylogeny and integrating its study with other properties of organisms. PMID:24787621

Workforce Planning in the Intelligence Community: A Retrospective

DTIC Science & Technology

2013-01-01

segments of this work. We also wish to thank Dwayne M. Butler and Nelson Lim from RAND and Robert B. Murrett of the Syracuse University Department of Public...Taylor, Richard Eisenman, William Fedorochko, Clifford M. Graf II, Mark Hoyer, Paul Bracken, Norman T. O’Meara, Jerry M. Sollinger, Judith Larson

Project Clarion: Three Years of Science Instruction in Title I Schools among K-Third Grade Students

NASA Astrophysics Data System (ADS)

Kim, Kyung Hee; VanTassel-Baska, Joyce; Bracken, Bruce A.; Feng, Annie; Stambaugh, Tamra; Bland, Lori

2012-10-01

The purpose of the study was to measure the effects of higher level, inquiry-based science curricula on students at primary level in Title I schools. Approximately 3,300 K-3 students from six schools were assigned to experimental or control classes ( N = 115 total) on a random basis according to class. Experimental students were exposed to concept-based science curriculum that emphasized `deep learning' though concept mastery and investigation, whereas control classes learned science from traditional school-based curricula. Two ability measures, the Bracken Basic Concept Scale-Revised (BBCS-R, Bracken 1998) and the Naglieri Nonverbal Intelligence Test (NNAT, Naglieri 1991), were used for baseline information. Additionally, a standardized measure of student achievement in science (the MAT-8 science subtest), a standardized measure of critical thinking, and a measure for observing teachers' classroom behaviors were used to assess learning outcomes. Results indicated that all ability groups of students benefited from the science inquiry-based approach to learning that emphasized science concepts, and that there was a positive achievement effect for low socio-economic young children who were exposed to such a curriculum.

Genome size expansion and the relationship between nuclear DNA content and spore size in the Asplenium monanthes fern complex (Aspleniaceae)

PubMed Central

2013-01-01

Background Homosporous ferns are distinctive amongst the land plant lineages for their high chromosome numbers and enigmatic genomes. Genome size measurements are an under exploited tool in homosporous ferns and show great potential to provide an overview of the mechanisms that define genome evolution in these ferns. The aim of this study is to investigate the evolution of genome size and the relationship between genome size and spore size within the apomictic Asplenium monanthes fern complex and related lineages. Results Comparative analyses to test for a relationship between spore size and genome size show that they are not correlated. The data do however provide evidence for marked genome size variation between species in this group. These results indicate that Asplenium monanthes has undergone a two-fold expansion in genome size. Conclusions Our findings challenge the widely held assumption that spore size can be used to infer ploidy levels within apomictic fern complexes. We argue that the observed genome size variation is likely to have arisen via increases in both chromosome number due to polyploidy and chromosome size due to amplification of repetitive DNA (e.g. transposable elements, especially retrotransposons). However, to date the latter has not been considered to be an important process of genome evolution within homosporous ferns. We infer that genome evolution, at least in some homosporous fern lineages, is a more dynamic process than existing studies would suggest. PMID:24354467

Invasion of a partially cut oak stand by hayscented fern

Treesearch

J.W. Groninger; L.H. McCormick

1991-01-01

Hardwood forests in Pennsylvania frequently develop a dense understory of hayscented fern (Dennstaedtia punctilobula (Michx.) Moore)) following partial overstory removal. Seedlings of desirable hardwood species are unable to develop in these understories. A study was conducted in a central Pennsylvania mixed oak stand to determine how hayscented fern...

On the widespread capacity for, and functional significance of, extreme inbreeding in ferns.

PubMed

Sessa, Emily B; Testo, Weston L; Watkins, James E

2016-08-01

Homosporous vascular plants utilize three different mating systems, one of which, gametophytic selfing, is an extreme form of inbreeding only possible in homosporous groups. This mating system results in complete homozygosity in all progeny and has important evolutionary and ecological implications. Ferns are the largest group of homosporous land plants, and the significance of extreme inbreeding for fern evolution has been a subject of debate for decades. We cultured gametophytes in the laboratory and quantified the relative frequencies of sporophyte production from isolated and paired gametophytes, and examined associations between breeding systems and several ecological and evolutionary traits. The majority of fern species studied show a capacity for gametophytic selfing, producing sporophytes from both isolated and paired gametophytes. While we did not follow sporophytes to maturity to investigate potential detrimental effects of homozygosity at later developmental stages, our results suggest that gametophytic selfing may have greater significance for fern evolution and diversification than has previously been realized. We present evidence from the largest study of mating behavior in ferns to date that the capacity for extreme inbreeding is prevalent in this lineage, and we discuss its implications and relevance and make recommendations for future studies of fern mating systems. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

Sequencing of small RNAs of the fern Pleopeltis minima (Polypodiaceae) offers insight into the evolution of the microrna repertoire in land plants

PubMed Central

Berruezo, Florencia; de Souza, Flávio S. J.; Picca, Pablo I.; Nemirovsky, Sergio I.; Martínez Tosar, Leandro; Rivero, Mercedes; Mentaberry, Alejandro N.

2017-01-01

MicroRNAs (miRNAs) are short, single stranded RNA molecules that regulate the stability and translation of messenger RNAs in diverse eukaryotic groups. Several miRNA genes are of ancient origin and have been maintained in the genomes of animal and plant taxa for hundreds of millions of years, playing key roles in development and physiology. In the last decade, genome and small RNA (sRNA) sequencing of several plant species have helped unveil the evolutionary history of land plants. Among these, the fern group (monilophytes) occupies a key phylogenetic position, as it represents the closest extant cousin taxon of seed plants, i.e. gymno- and angiosperms. However, in spite of their evolutionary, economic and ecological importance, no fern genome has been sequenced yet and few genomic resources are available for this group. Here, we sequenced the small RNA fraction of an epiphytic South American fern, Pleopeltis minima (Polypodiaceae), and compared it to plant miRNA databases, allowing for the identification of miRNA families that are shared by all land plants, shared by all vascular plants (tracheophytes) or shared by euphyllophytes (ferns and seed plants) only. Using the recently described transcriptome of another fern, Lygodium japonicum, we also estimated the degree of conservation of fern miRNA targets in relation to other plant groups. Our results pinpoint the origin of several miRNA families in the land plant evolutionary tree with more precision and are a resource for future genomic and functional studies of fern miRNAs. PMID:28494025

Sequencing of small RNAs of the fern Pleopeltis minima (Polypodiaceae) offers insight into the evolution of the microrna repertoire in land plants.

PubMed

Berruezo, Florencia; de Souza, Flávio S J; Picca, Pablo I; Nemirovsky, Sergio I; Martínez Tosar, Leandro; Rivero, Mercedes; Mentaberry, Alejandro N; Zelada, Alicia M

2017-01-01

MicroRNAs (miRNAs) are short, single stranded RNA molecules that regulate the stability and translation of messenger RNAs in diverse eukaryotic groups. Several miRNA genes are of ancient origin and have been maintained in the genomes of animal and plant taxa for hundreds of millions of years, playing key roles in development and physiology. In the last decade, genome and small RNA (sRNA) sequencing of several plant species have helped unveil the evolutionary history of land plants. Among these, the fern group (monilophytes) occupies a key phylogenetic position, as it represents the closest extant cousin taxon of seed plants, i.e. gymno- and angiosperms. However, in spite of their evolutionary, economic and ecological importance, no fern genome has been sequenced yet and few genomic resources are available for this group. Here, we sequenced the small RNA fraction of an epiphytic South American fern, Pleopeltis minima (Polypodiaceae), and compared it to plant miRNA databases, allowing for the identification of miRNA families that are shared by all land plants, shared by all vascular plants (tracheophytes) or shared by euphyllophytes (ferns and seed plants) only. Using the recently described transcriptome of another fern, Lygodium japonicum, we also estimated the degree of conservation of fern miRNA targets in relation to other plant groups. Our results pinpoint the origin of several miRNA families in the land plant evolutionary tree with more precision and are a resource for future genomic and functional studies of fern miRNAs.

rbcL gene sequences provide evidence for the evolutionary lineages of leptosporangiate ferns.

PubMed

Hasebe, M; Omori, T; Nakazawa, M; Sano, T; Kato, M; Iwatsuki, K

1994-06-07

Pteriodophytes have a longer evolutionary history than any other vascular land plant and, therefore, have endured greater loss of phylogenetically informative information. This factor has resulted in substantial disagreements in evaluating characters and, thus, controversy in establishing a stable classification. To compare competing classifications, we obtained DNA sequences of a chloroplast gene. The sequence of 1206 nt of the large subunit of the ribulose-bisphosphate carboxylase gene (rbcL) was determined from 58 species, representing almost all families of leptosporangiate ferns. Phlogenetic trees were inferred by the neighbor-joining and the parsimony methods. The two methods produced almost identical phylogenetic trees that provided insights concerning major general evolutionary trends in the leptosporangiate ferns. Interesting findings were as follows: (i) two morphologically distinct heterosporous water ferns, Marsilea and Salvinia, are sister genera; (ii) the tree ferns (Cyatheaceae, Dicksoniaceae, and Metaxyaceae) are monophyletic; and (iii) polypodioids are distantly related to the gleichenioids in spite of the similarity of their exindusiate soral morphology and are close to the higher indusiate ferns. In addition, the affinities of several "problematic genera" were assessed.

Two new fern chloroplasts and decelerated evolution linked to the long generation time in tree ferns.

PubMed

Zhong, Bojian; Fong, Richard; Collins, Lesley J; McLenachan, Patricia A; Penny, David

2014-04-30

We report the chloroplast genomes of a tree fern (Dicksonia squarrosa) and a "fern ally" (Tmesipteris elongata), and show that the phylogeny of early land plants is basically as expected, and the estimates of divergence time are largely unaffected after removing the fastest evolving sites. The tree fern shows the major reduction in the rate of evolution, and there has been a major slowdown in the rate of mutation in both families of tree ferns. We suggest that this is related to a generation time effect; if there is a long time period between generations, then this is probably incompatible with a high mutation rate because otherwise nearly every propagule would probably have several lethal mutations. This effect will be especially strong in organisms that have large numbers of cell divisions between generations. This shows the necessity of going beyond phylogeny and integrating its study with other properties of organisms. © The Author(s) 2014. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Crowding and Cognitive Development: The Mediating Role of Maternal Responsiveness among 36-Month-Old Children

ERIC Educational Resources Information Center

Evans, Gary W.; Ricciuti, Henry N.; Hope, Steven; Schoon, Ingrid; Bradley, Robert H.; Corwyn, Robert F.; Hazan, Cindy

2010-01-01

Residential crowding in both U.S. and U.K. samples of 36-month-old children is related concurrently to the Bracken scale, a standard index of early cognitive development skills including letter and color identification, shape recognition, and elementary numeric comprehension. In the U.S. sample, these effects also replicate prospectively.…

Profile Analysis of Deaf Children Using the Universal Nonverbal Intelligence Test

ERIC Educational Resources Information Center

Krivitski, Erin C.; McIntosh, David E.; Rothlisberg, Barbara; Finch, Holmes

2004-01-01

This study was conducted to determine whether children who are deaf perform similarly to hearing children on the Universal Nonverbal Intelligence Test (UNIT; Bracken & McCallum, 1998). The children classified as deaf demonstrated a hearing loss of 60 dB or more, were prelingually deaf, and did not exhibit co-morbidity. They were matched on…

Cultural-Linguistic Test Adaptations: Guidelines for Selection, Alteration, Use, and Review

ERIC Educational Resources Information Center

Krach, S. Kathleen; McCreery, Michael P.; Guerard, Jessika

2017-01-01

In 1991, Bracken and Barona wrote an article for "School Psychology International" focusing on state of the art procedures for translating and using tests across multiple languages. Considerable progress has been achieved in this area over the 25 years between that publication and today. This article seeks to provide a more current set…

Psychological Well-Being in Adolescence: The Contribution of Interpersonal Relations and Experience of Being Alone

ERIC Educational Resources Information Center

Corsano, Paola; Majorano, Marinella; Champretavy, Lorella

2006-01-01

This study investigated the influence of loneliness and relationships with parents and friends on the psychological well-being or adolescent malaise. Data were collected via two questionnaires (LLCA--Marcoen, Goossens & Caes, 1987; TRI--Bracken, 1996) from a sample of 330 Italian adolescents, males and females, aged between 11 and 19. As…

Ferns are less dependent on passive dilution by cell expansion to coordinate leaf vein and stomatal spacing than angiosperms

PubMed Central

Jordan, Gregory J.; Brodribb, Timothy J.

2017-01-01

Producing leaves with closely spaced veins is a key innovation linked to high rates of photosynthesis in angiosperms. A close geometric link between veins and stomata in angiosperms ensures that investment in enhanced venous water transport provides the strongest net carbon return to the plant. This link is underpinned by “passive dilution” via expansion of surrounding cells. However, it is not known whether this ‘passive dilution’ mechanism is present in plant lineages other than angiosperms and is another key feature of the angiosperms’ evolutionary success. Consequently, we sought to determine whether the ‘passive dilution’ mechanism is; (i) exclusive to the angiosperms, (ii) a conserved mechanism that evolved in the common ancestor of ferns and angiosperms, or (iii) has evolved continuously over time. To do this we first we assessed the plasticity of vein and stomatal density and epidermal cell size in ferns in response to light environment. We then compared the relationships between these traits found among ferns with modelled relationships that assume vein and stomatal density respond passively to epidermal cell expansion, and with those previously observed in angiosperms. Vein density, stomatal density and epidermal cell size were linked in ferns with remarkably similar relationships to those observed in angiosperms, except that fern leaves had fewer veins per stomata. However, plasticity was limited in ferns and stomatal spacing was dependent on active stomatal differentiation as well as passive cell expansion. Thus, ferns (like angiosperms) appear to coordinate vein and stomatal density with epidermal cell expansion to some extent to maintain a constant ratio between veins and stomata in the leaf. The different general relationships between vein density and stomatal density in ferns and angiosperms suggests the groups have different optimum balances between the production of vein tissue dedicated to water supply and stomatal tissue for gas exchange. PMID:28953931

Distribution, dispersal and abundance of hayscented fern spores in mixed hardwood stands

Treesearch

Larry H. McCormick; Kathy A. Penrod

1995-01-01

A study was conducted in 1992 to assess the abundance and distribution of viable hayscented fern spores in the forest floor of central Pennsylvania hardwood stands before and after seasonal spore dispersal. Intact soil samples were collected at various distances and directions from established fern communities and placed in a greenhouse to effect spore germination....

Distribution and dynamics of hayscented fern following stand harvest

Treesearch

Songlin Fei; Peter J. Gould; Melanie J. Kaeser; Kim C. Steiner

2008-01-01

The distribution and dynamics of hayscented fern were examined as part of a large-scale study of oak regeneration in Pennsylvania. The study included 69 stands covering 3,333 acres in two physiographic provinces. Hayscented fern was more widely distributed and occurred at higher densities in the Allegheny Plateau physiographic provinces versus the Ridge and Valley...

Hay-scented fern spore production following clearcutting

Treesearch

Kathy A. Penrod; Larry H. McCormick

1997-01-01

Hay-scented fern is a common forest understory weed native to the Appalachian region. It interferes with oak and other hardwood seedling growth and often leads to regeneration failures. Harvesting is know to increase rates of vegetative expansion, spore germination, and possibly spore production of hay-scented fern. To examine the latter effect, a progressive series of...

Different leaf cost-benefit strategies of ferns distributed in contrasting light habitats of sub-tropical forests.

PubMed

Zhu, Shi-Dan; Li, Rong-Hua; Song, Juan; He, Peng-Cheng; Liu, Hui; Berninger, Frank; Ye, Qing

2016-03-01

Ferns are abundant in sub-tropical forests in southern China, with some species being restricted to shaded understorey of natural forests, while others are widespread in disturbed, open habitats. To explain this distribution pattern, we hypothesize that ferns that occur in disturbed forests (FDF) have a different leaf cost-benefit strategy compared with ferns that occur in natural forests (FNF), with a quicker return on carbon investment in disturbed habitats compared with old-growth forests. We chose 16 fern species from contrasting light habitats (eight FDF and eight FNF) and studied leaf functional traits, including leaf life span (LLS), specific leaf area (SLA), leaf nitrogen and phosphorus concentrations (N and P), maximum net photosynthetic rates (A), leaf construction cost (CC) and payback time (PBT), to conduct a leaf cost-benefit analysis for the two fern groups. The two groups, FDF and FNF, did not differ significantly in SLA, leaf N and P, and CC, but FDF had significantly higher A, greater photosynthetic nitrogen- and phosphorus-use efficiencies (PNUE and PPUE), and shorter PBT and LLS compared with FNF. Further, across the 16 fern species, LLS was significantly correlated with A, PNUE, PPUE and PBT, but not with SLA and CC. Our results demonstrate that leaf cost-benefit analysis contributes to understanding the distribution pattern of ferns in contrasting light habitats of sub-tropical forests: FDF employing a quick-return strategy can pre-empt resources and rapidly grow in the high-resource environment of open habitats; while a slow-return strategy in FNF allows their persistence in the shaded understorey of old-growth forests. © The Author 2015. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Different leaf cost–benefit strategies of ferns distributed in contrasting light habitats of sub-tropical forests

PubMed Central

Zhu, Shi-Dan; Li, Rong-Hua; Song, Juan; He, Peng-Cheng; Liu, Hui; Berninger, Frank; Ye, Qing

2016-01-01

Background and Aims Ferns are abundant in sub-tropical forests in southern China, with some species being restricted to shaded understorey of natural forests, while others are widespread in disturbed, open habitats. To explain this distribution pattern, we hypothesize that ferns that occur in disturbed forests (FDF) have a different leaf cost–benefit strategy compared with ferns that occur in natural forests (FNF), with a quicker return on carbon investment in disturbed habitats compared with old-growth forests. Methods We chose 16 fern species from contrasting light habitats (eight FDF and eight FNF) and studied leaf functional traits, including leaf life span (LLS), specific leaf area (SLA), leaf nitrogen and phosphorus concentrations (N and P), maximum net photosynthetic rates (A), leaf construction cost (CC) and payback time (PBT), to conduct a leaf cost–benefit analysis for the two fern groups. Key Results The two groups, FDF and FNF, did not differ significantly in SLA, leaf N and P, and CC, but FDF had significantly higher A, greater photosynthetic nitrogen- and phosphorus-use efficiencies (PNUE and PPUE), and shorter PBT and LLS compared with FNF. Further, across the 16 fern species, LLS was significantly correlated with A, PNUE, PPUE and PBT, but not with SLA and CC. Conclusions Our results demonstrate that leaf cost–benefit analysis contributes to understanding the distribution pattern of ferns in contrasting light habitats of sub-tropical forests: FDF employing a quick-return strategy can pre-empt resources and rapidly grow in the high-resource environment of open habitats; while a slow-return strategy in FNF allows their persistence in the shaded understorey of old-growth forests. PMID:26684751

Metabolic Adaptation, a Specialized Leaf Organ Structure and Vascular Responses to Diurnal N2 Fixation by Nostoc azollae Sustain the Astonishing Productivity of Azolla Ferns without Nitrogen Fertilizer

PubMed Central

Brouwer, Paul; Bräutigam, Andrea; Buijs, Valerie A.; Tazelaar, Anne O. E.; van der Werf, Adrie; Schlüter, Urte; Reichart, Gert-Jan; Bolger, Anthony; Usadel, Björn; Weber, Andreas P. M.; Schluepmann, Henriette

2017-01-01

Sustainable agriculture demands reduced input of man-made nitrogen (N) fertilizer, yet N2 fixation limits the productivity of crops with heterotrophic diazotrophic bacterial symbionts. We investigated floating ferns from the genus Azolla that host phototrophic diazotrophic Nostoc azollae in leaf pockets and belong to the fastest growing plants. Experimental production reported here demonstrated N-fertilizer independent production of nitrogen-rich biomass with an annual yield potential per ha of 1200 kg−1 N fixed and 35 t dry biomass. 15N2 fixation peaked at noon, reaching 0.4 mg N g−1 dry weight h−1. Azolla ferns therefore merit consideration as protein crops in spite of the fact that little is known about the fern’s physiology to enable domestication. To gain an understanding of their nitrogen physiology, analyses of fern diel transcript profiles under differing nitrogen fertilizer regimes were combined with microscopic observations. Results established that the ferns adapted to the phototrophic N2-fixing symbionts N. azollae by (1) adjusting metabolically to nightly absence of N supply using responses ancestral to ferns and seed plants; (2) developing a specialized xylem-rich vasculature surrounding the leaf-pocket organ; (3) responding to N-supply by controlling transcripts of genes mediating nutrient transport, allocation and vasculature development. Unlike other non-seed plants, the Azolla fern clock is shown to contain both the morning and evening loops; the evening loop is known to control rhythmic gene expression in the vasculature of seed plants and therefore may have evolved along with the vasculature in the ancestor of ferns and seed plants. PMID:28408911

Tree ferns: monophyletic groups and their relationships as revealed by four protein-coding plastid loci.

PubMed

Korall, Petra; Pryer, Kathleen M; Metzgar, Jordan S; Schneider, Harald; Conant, David S

2006-06-01

Tree ferns are a well-established clade within leptosporangiate ferns. Most of the 600 species (in seven families and 13 genera) are arborescent, but considerable morphological variability exists, spanning the giant scaly tree ferns (Cyatheaceae), the low, erect plants (Plagiogyriaceae), and the diminutive endemics of the Guayana Highlands (Hymenophyllopsidaceae). In this study, we investigate phylogenetic relationships within tree ferns based on analyses of four protein-coding, plastid loci (atpA, atpB, rbcL, and rps4). Our results reveal four well-supported clades, with genera of Dicksoniaceae (sensu ) interspersed among them: (A) (Loxomataceae, (Culcita, Plagiogyriaceae)), (B) (Calochlaena, (Dicksonia, Lophosoriaceae)), (C) Cibotium, and (D) Cyatheaceae, with Hymenophyllopsidaceae nested within. How these four groups are related to one other, to Thyrsopteris, or to Metaxyaceae is weakly supported. Our results show that Dicksoniaceae and Cyatheaceae, as currently recognised, are not monophyletic and new circumscriptions for these families are needed.

Comptonia peregrina

Treesearch

Paula M. Pijut

2004-01-01

Sweet fern is a densely branched, deciduous, rhizomatous shrub that grows 0.5 to 1.5 m tall and 1.2 to 2.5 m wide or more (Dirr 1998, Gleason and Cronquist 1991). Sweet fern is a dioecious or seldom monoecious (Gleason and Cronquist 1991), actinorhizal nitrogen-fixing shrub (Del Tredici 1996, Ziegler and Huser 1963) with fern-like leaves and stems that are aromatic...

Ecological Design of Fernery based on Bioregion Classification System in Ecopark Cibinong Science Center Botanic Gardens, Indonesia

NASA Astrophysics Data System (ADS)

Nafar, S.; Gunawan, A.

2017-10-01

Indonesia as mega biodiversity country has a wide variety of ferns. However, the natural habitats of ferns are currently degrading, particularly in lowlands due to the increasing level of urban-sprawl and industrial zones development. Therefore, Ecology Park (Ecopark) Cibinong Science Center-Botanic Gardens as an ex-situ conservation area is expected to be the best location to conserve the lowland ferns. The purpose of this study is to design a fernery through an ecological landscape design process. The main concept is The Journey of Fern, this concept aiming on providing users experiences in fernery by associating conservational, educational, and recreational aspects. Ecological landscape design as general is applied by the principal of reduce, reuse, and recycle (3R). Bioregion classification system is applied by grouping the plants based on the characteristics of light, water, soil, air, and temperature. The design concept is inspired by the morphology of fern and its growth patterns which is transformed into organic and geometric forms. The result of this study is a design of fernery which consist of welcome area, recreation area, service area, and conservation education area as the main area that providing 66 species of ferns.

Different slopes of a mountain can determine the structure of ferns and lycophytes communities in a tropical forest of Brazil.

PubMed

Nettesheim, Felipe C; Damasceno, Elaine R; Sylvestre, Lana S

2014-03-01

A community of Ferns and Lycophytes was investigated by comparing the occurrence of species on different slopes of a paleoisland in Southeastern Brazil. Our goal was to evaluate the hypothesis that slopes with different geographic orientations determine a differentiation of Atlantic Forest ferns and lycophytes community. We recorded these plants at slopes turned towards the continent and at slopes turned towards the open sea. Analysis consisted of a preliminary assessment on fern beta diversity, a Non Metric Multidimensional Scaling (NMDS) and a Student t-test to confirm if sites sampling units ordination was different at each axis. We further used the Pearson coefficient to relate fern species to the differentiation pattern and again Student's t-test to determine if richness, plant cover and abundance varied between the two sites. There was a relatively low number of shared species between the two sites and ferns and lycophytes community variation was confirmed. Some species were detected as indicators of the community variation but we were unable to detect richness, plant cover or abundance differences. Despite the evidence of this variation between the slopes, further works are needed to evaluate which processes are contributing to determine this pattern.

Evolutionary Conservation of ABA Signaling for Stomatal Closure1[OPEN

PubMed Central

Huang, Yuqing; Dai, Fei; Franks, Peter J.; Nevo, Eviatar; Soltis, Douglas E.; Soltis, Pamela S.; Xue, Dawei; Zhang, Guoping; Pogson, Barry J.

2017-01-01

Abscisic acid (ABA)-driven stomatal regulation reportedly evolved after the divergence of ferns, during the early evolution of seed plants approximately 360 million years ago. This hypothesis is based on the observation that the stomata of certain fern species are unresponsive to ABA, but exhibit passive hydraulic control. However, ABA-induced stomatal closure was detected in some mosses and lycophytes. Here, we observed that a number of ABA signaling and membrane transporter protein families diversified over the evolutionary history of land plants. The aquatic ferns Azolla filiculoides and Salvinia cucullata have representatives of 23 families of proteins orthologous to those of Arabidopsis (Arabidopsis thaliana) and all other land plant species studied. Phylogenetic analysis of the key ABA signaling proteins indicates an evolutionarily conserved stomatal response to ABA. Moreover, comparative transcriptomic analysis has identified a suite of ABA-responsive genes that differentially expressed in a terrestrial fern species, Polystichum proliferum. These genes encode proteins associated with ABA biosynthesis, transport, reception, transcription, signaling, and ion and sugar transport, which fit the general ABA signaling pathway constructed from Arabidopsis and Hordeum vulgare. The retention of these key ABA-responsive genes could have had a profound effect on the adaptation of ferns to dry conditions. Furthermore, stomatal assays have shown the primary evidence for ABA-induced closure of stomata in two terrestrial fern species P. proliferum and Nephrolepis exaltata. In summary, we report, to our knowledge, new molecular and physiological evidence for the presence of active stomatal control in ferns. PMID:28232585

Stable Transformation of Ferns Using Spores as Targets: Pteris vittata and Ceratopteris thalictroides1[W][OPEN

PubMed Central

Muthukumar, Balasubramaniam; Joyce, Blake L.; Elless, Mark P.; Stewart, C. Neal

2013-01-01

Ferns (Pteridophyta) are very important members of the plant kingdom that lag behind other taxa with regards to our understanding of their genetics, genomics, and molecular biology. We report here, to our knowledge, the first instance of stable transformation of fern with recovery of transgenic sporophytes. Spores of the arsenic hyperaccumulating fern Pteris vittata and tetraploid ‘C-fern Express’ (Ceratopteris thalictroides) were stably transformed by Agrobacterium tumefaciens with constructs containing the P. vittata actin promoter driving a GUSPlus reporter gene. Reporter gene expression assays were performed on multiple tissues and growth stages of gametophytes and sporophytes. Southern-blot analysis confirmed stable transgene integration in recovered sporophytes and also confirmed that no plasmid from A. tumefaciens was present in the sporophyte tissues. We recovered seven independent transformants of P. vittata and four independent C. thalictroides transgenics. Inheritance analyses using β-glucuronidase (GUS) histochemical staining revealed that the GUS transgene was stably expressed in second generation C. thalictroides sporophytic tissues. In an independent experiment, the gusA gene that was driven by the 2× Cauliflower mosaic virus 35S promoter was bombarded into P. vittata spores using biolistics, in which putatively stable transgenic gametophytes were recovered. Transformation procedures required no tissue culture or selectable marker genes. However, we did attempt to use hygromycin selection, which was ineffective for recovering transgenic ferns. This simple stable transformation method should help facilitate functional genomics studies in ferns. PMID:23933990

Comparing Gifted and Nongifted African American and Euro-American Students on Cognitive and Academic Variables Using Local Norms

ERIC Educational Resources Information Center

Jordan, Kelli R.; Bain, Sherry K.; McCallum, R. Steve; Mee Bell, Sherry

2012-01-01

A total of 47 gifted and nongifted African American and Euro-American elementary students were rated by their teachers on a multidimensional instrument developed to minimize language considerations and to rely on local norms (Universal Multiple Abilities Scales [UMAS; McCallum & Bracken, 2012a]). Results from two factorial MANOVAs revealed no…

A comparison of conifers planted on the Hemlock Experimental Forest.

Treesearch

Norman P. Worthington

1955-01-01

Test plantings have been made on the Hemlock Experimental Forest in cooperation with the St. Regis Paper Company to test suitability of several native conifers for planting on heavy bracken and brush-covered Site II areas typical of the western Olympic Peninsula. In the spring of 1950, 2,500 Douglas-fir seedlings from the Forest Industries Tree Nursery at Nisqually...

Test Reviews: Bracken, B. A., & Howell, K. (2004). "Clinical Assessment of Depression." Odessa, FL: Psychological Assessment Resources

ERIC Educational Resources Information Center

Aghakhani, Anoosha; Chan, Eric K.

2007-01-01

In this article, the authors review the Clinical Assessment of Depression (CAD), a 50-item self-report measure of depressive symptoms designed for children, adolescents, adults, and elderly adults from 8 to 79 years of age. Purporting to be sensitive to depressive symptomatology across the lifespan, the test items were written to reflect the…

Effects of a Tall Ship Sail Training Experience on Adolescents' Self-Concept

ERIC Educational Resources Information Center

Capurso, Michele; Borsci, Simone

2013-01-01

This study investigates the impact of a sail training education programme on the self-concept of a group of 147 adolescents. The Competence and Social domains of Bracken's self-concept scale were assessed by a quasi-experimental design in three phases: before commencement of the activities, on the last day of the voyage, and three months after…

Distribution and dynamics of the invasive native hay-scented fern

Treesearch

Songlin Fei; Peter Gould; Melanie Kaeser; Kim Steiner

2010-01-01

The spread and dominance of the invasive native hay-scented fern in the understory is one of the most significant changes to affect the forest ecosystems in the northeastern United States in the last century. We studied changes in the distribution and dynamics of hay-scented fern at a large scale over a 10-yr period in Pennsylvania. The study included 56 stands...

Understory fern community structure, growth and spore production responses to a large-scale hurricane experiment in a Puerto Rico rainforest

Treesearch

Joanne M. Sharpe; Aaron B. Shiels

2014-01-01

Ferns are abundant in most rainforest understories yet their responses to hurricanes have not been well studied. Fern community structure, growth and spore production were monitored for two years before and five years after a large-scale experiment that simulated two key components of severe hurricane disturbance: canopy openness and debris deposition. The canopy was...

A new conceptual framework for water and sediment connectivity

NASA Astrophysics Data System (ADS)

Keesstra, Saskia; Cerdà, Artemi; Parsons, Tony; Nunes, Joao Pedro; Saco, Patricia

2016-04-01

For many years scientists have tried to understand, describe and quantify sediment transport on multiple scales; from the geomorphological work triggered by a single thunderstorm to the geological time scale land scape evolution, and from particles and soil aggregates up to the continental scale. In the last two decades, a new concept called connectivity (Baartman et al., 2013; Bracken et al., 2013, 2015; Parsons et al., 2015) has been used by the scientific community to describe the connection between the different scales at which the sediment redistribution research along the watershed are being studied: pedon, slope tram, slope, watersheds, and basins. This concept is seen as a means to describe and quantify the results of processes influencing the transport of sediment on all these scales. Therefore the concept of connectivity and the way scales are used in the design of a measurement and monitoring scheme are interconnected (Cerdà et al., 2012), which shows that connectivity is not only a tool for process understanding, but also a tool to measure processes on multiple scales. This research aims to describe catchment system dynamics from a connectivity point of view. This conceptual framework can be helpful to look at catchment systems and synthesize which data are necessary to take into account when measuring or modelling water and sediment transfer in catchment systems, Identifying common patterns and generalities will help discover physical reasons for differences in responses and interaction between these processes. We describe a conceptual framework which is meant to bring a better understanding of the system dynamics of a catchment in terms of water and sediment transfer by breaking apart the system dynamics in stocks (the system state at a given moment) and flows (the system fluxes). Breaking apart the internal system dynamics that determine the behaviour of the catchment system is in our opinion a way to bring a better insight into the concepts of hydrological and sediment connectivity as described in previous research by Bracken et al (2013, 2015). By looking at the individual parts of the system, it becomes more manageable and less conceptual, which is important because we have to indicate where the research on connectivity should focus on. With this approach, processes and feedbacks in the catchment system can be pulled apart to study separately, making the system understandable and measureable, which will enable parameterization of models with actual measured data. The approach we took in describing water and sediment transfer is to first assess how they work in a system in dynamic equilibrium. After describing this, an assessment is made of how such dynamic equilibriums can be taken out of balance by an external push. Baartman, J.E.M., Masselink, R.H., Keesstra, S.D., Temme, A.J.A.M., 2013. Linking landscape morphological complexity and sediment connectivity. Earth Surface Processes and Landforms 38: 1457-1471. Bracken, L.J., Wainwright, J., Ali, G.A., Tetzlaff, D., Smith, M.W., Reaney, S.M., and Roy, A.G. 2013. Concepts of hydrological connectivity: research approaches, pathways and future agendas. Earth Science Reviews, 119, 17-34. Bracken, L.J., Turnbull, L, Wainwright, J. and Boogart, P. Submitted. Sediment Connectivity: A Framework for Understanding Sediment Transfer at Multiple Scales. Earth Surface Processes and Landforms. Cerdà, A., Brazier, R., Nearing, M., and de Vente, J. 2012. scales and erosion. Catena, 102, 1-2. doi:10.1016/j.catena.2011.09.006 Parsons A.J., Bracken L., Peoppl , R., Wainwright J., Keesstra, S.D., 2015. Editorial: Introduction to special issue on connectivity in water and sediment dynamics. In press in Earth Surface Processes and Landforms. DOI: 10.1002/esp.3714

Medicinal Properties of Adiantum capillus-veneris Linn. in Traditional Medicine and Modern Phytotherapy: A Review Article.

PubMed

Dehdari, Sahar; Hajimehdipoor, Homa

2018-02-01

Adiantum capillus-veneris Linn (Maidenhair fern) is an herb belonging to the family Pteridaceae. It is named as " Pare-siavashan " in medical and pharmaceutical textbooks of Iranian Traditional Medicine. The fronds of Maidenhair fern were mainly administrated by ancient physicians as single medicine or in combination with other plants in multi-herbal formulations for curing different diseases. Because of different chemical compositions, the herb fronds were also assessed for its numerous pharmacological effects. Therefore, the current study was done to review the traditional usage and modern pharmacological and toxicological effects of Maidenhair fern. Scientific databases and publications including Web of Science, PubMed, Scopus, Science direct, Cochrane Library, SID (for Persian papers) and medical and pharmaceutical textbooks of traditional medicine as well were searched for " Adiantum capillus-veneris ", " Maidenhair fern " and " Pare-siavashan " without limitation up to 2016. Maidenhair fern exhibited to possess anti-diabetic, anticonvulsant, analgesic, hypocholesterolemic, goitrogenic, anti-thyroidal, antibacterial, antifungal, wound healing, antiobesity, anti hair loss, anti-asthmatic, anti-inflammatory, antidiarrheal and antispasmodic, antioxidant as well as diuretic, anti-urolithiatic and detoxifying effects in modern medicine. Ancient physicians declared some of the confirmed pharmacological effects. Maidenhair fern frond can be a good candidate for clinical purpose. Therefore, future researches on the other mentioned effects in traditional medicine are recommended.

Accuracy of 3D Imaging Software in Cephalometric Analysis

DTIC Science & Technology

2013-06-21

submitted to the Faculty of the Comprehensive Dentistry Graduate Program Naval Postgraduate Dental School Uniformed Services University of the Health...Sciences in partial fulfillment of the requirements of the degree of Master of Science in Oral Biology June 2013 Naval Postgraduate Dental ...Master’s thesis of Bracken Robert Godfrey Lieutenant Commander, Dental Corps, U.S. Navy has been approved by the Examining Committee for the

The Rev. John Bracken v. the Visitors of William and Mary College: A Post-Revolutionary Problem in Visitatorial Jurisdiction.

ERIC Educational Resources Information Center

Bridge, J. W.

1979-01-01

Reforms in 1779 at the College of William and Mary caused a professor to be dismissed, after which he took legal action against the institution. It is concluded that English corporate law was abused in defending against the professor's action. (Journal availability: College of William and Mary, Williamsburg, VA 23185, $3.00.) (MSE)

Evaluation of Floors and Item Gradients for Reading and Math Tests for Young Children

ERIC Educational Resources Information Center

Bradley-Johnson, Sharon; Durmusoglu, Gokce

2005-01-01

Ignoring the adequacy of floors and item gradients for tests used with young children can have serious consequences. Thus, because of the importance of early intervention for reading and math problems, we used the criteria suggested by Bracken for adequate floors and item gradients, and reviewed 15 reading tests and 12 math tests for ages 4-0…

Elfin Woodland Recovery 30 years After a Plane Wreck in Puerto Rico’s Luquillo Mountains

Treesearch

PETER L.WEAVER

2000-01-01

Grasses and ferns characterized the recovery of elfin woodland for the first 18 years after a December 1968 airplane crash. From 1986 to 1998, ferns and woody dicots were prominent and the total aboveground dry weight biomass increased from 775 to 2210 g/m2. Woody dicots increased 3.5 times, palms 1.3 times, and ferns 4.4 times above their 1986 levels. Grasses and...

Using high resolution computed tomography to visualize the three dimensional structure and function of plant vasculature.

PubMed

McElrone, Andrew J; Choat, Brendan; Parkinson, Dilworth Y; MacDowell, Alastair A; Brodersen, Craig R

2013-04-05

High resolution x-ray computed tomography (HRCT) is a non-destructive diagnostic imaging technique with sub-micron resolution capability that is now being used to evaluate the structure and function of plant xylem network in three dimensions (3D) (e.g. Brodersen et al. 2010; 2011; 2012a,b). HRCT imaging is based on the same principles as medical CT systems, but a high intensity synchrotron x-ray source results in higher spatial resolution and decreased image acquisition time. Here, we demonstrate in detail how synchrotron-based HRCT (performed at the Advanced Light Source-LBNL Berkeley, CA, USA) in combination with Avizo software (VSG Inc., Burlington, MA, USA) is being used to explore plant xylem in excised tissue and living plants. This new imaging tool allows users to move beyond traditional static, 2D light or electron micrographs and study samples using virtual serial sections in any plane. An infinite number of slices in any orientation can be made on the same sample, a feature that is physically impossible using traditional microscopy methods. Results demonstrate that HRCT can be applied to both herbaceous and woody plant species, and a range of plant organs (i.e. leaves, petioles, stems, trunks, roots). Figures presented here help demonstrate both a range of representative plant vascular anatomy and the type of detail extracted from HRCT datasets, including scans for coast redwood (Sequoia sempervirens), walnut (Juglans spp.), oak (Quercus spp.), and maple (Acer spp.) tree saplings to sunflowers (Helianthus annuus), grapevines (Vitis spp.), and ferns (Pteridium aquilinum and Woodwardia fimbriata). Excised and dried samples from woody species are easiest to scan and typically yield the best images. However, recent improvements (i.e. more rapid scans and sample stabilization) have made it possible to use this visualization technique on green tissues (e.g. petioles) and in living plants. On occasion some shrinkage of hydrated green plant tissues will cause images to blur and methods to avoid these issues are described. These recent advances with HRCT provide promising new insights into plant vascular function.

Using High Resolution Computed Tomography to Visualize the Three Dimensional Structure and Function of Plant Vasculature

PubMed Central

McElrone, Andrew J.; Choat, Brendan; Parkinson, Dilworth Y.; MacDowell, Alastair A.; Brodersen, Craig R.

2013-01-01

High resolution x-ray computed tomography (HRCT) is a non-destructive diagnostic imaging technique with sub-micron resolution capability that is now being used to evaluate the structure and function of plant xylem network in three dimensions (3D) (e.g. Brodersen et al. 2010; 2011; 2012a,b). HRCT imaging is based on the same principles as medical CT systems, but a high intensity synchrotron x-ray source results in higher spatial resolution and decreased image acquisition time. Here, we demonstrate in detail how synchrotron-based HRCT (performed at the Advanced Light Source-LBNL Berkeley, CA, USA) in combination with Avizo software (VSG Inc., Burlington, MA, USA) is being used to explore plant xylem in excised tissue and living plants. This new imaging tool allows users to move beyond traditional static, 2D light or electron micrographs and study samples using virtual serial sections in any plane. An infinite number of slices in any orientation can be made on the same sample, a feature that is physically impossible using traditional microscopy methods. Results demonstrate that HRCT can be applied to both herbaceous and woody plant species, and a range of plant organs (i.e. leaves, petioles, stems, trunks, roots). Figures presented here help demonstrate both a range of representative plant vascular anatomy and the type of detail extracted from HRCT datasets, including scans for coast redwood (Sequoia sempervirens), walnut (Juglans spp.), oak (Quercus spp.), and maple (Acer spp.) tree saplings to sunflowers (Helianthus annuus), grapevines (Vitis spp.), and ferns (Pteridium aquilinum and Woodwardia fimbriata). Excised and dried samples from woody species are easiest to scan and typically yield the best images. However, recent improvements (i.e. more rapid scans and sample stabilization) have made it possible to use this visualization technique on green tissues (e.g. petioles) and in living plants. On occasion some shrinkage of hydrated green plant tissues will cause images to blur and methods to avoid these issues are described. These recent advances with HRCT provide promising new insights into plant vascular function. PMID:23609036

Are rates of species diversification and body size evolution coupled in the ferns?

PubMed

Testo, Weston L; Sundue, Michael A

2018-03-01

Understanding the relationship between phenotypic evolution and lineage diversification is a central goal of evolutionary biology. To extend our understanding of the role morphological evolution plays in the diversification of plants, we examined the relationship between leaf size evolution and lineage diversification across ferns. We tested for an association between body size evolution and lineage diversification using a comparative phylogenetic approach that combined a time-calibrated phylogeny and leaf size data set for 2654 fern species. Rates of leaf size change and lineage diversification were estimated using BAMM, and rate correlations were performed for rates obtained for all families and individual species. Rates and patterns of rate-rate correlation were also analyzed separately for terrestrial and epiphytic taxa. We find no significant correlation between rates of leaf area change and lineage diversification, nor was there a difference in this pattern when growth habit is considered. Our results are consistent with the findings of an earlier study that reported decoupled rates of body size evolution and diversification in the Polypodiaceae, but conflict with a recent study that reported a positive correlation between body size evolution and lineage diversification rates in the tree fern family Cyatheaceae. Our findings indicate that lineage diversification in ferns is largely decoupled from shifts in body size, in contrast to several other groups of organisms. Speciation in ferns appears to be primarily driven by hybridization and isolation along elevational gradients, rather than adaptive radiations featuring prominent morphological restructuring. The exceptional diversity of leaf morphologies in ferns appears to reflect a combination of ecophysiological constraints and adaptations that are not key innovations. © 2018 Botanical Society of America.

Chemical Composition of Soil Horizons and Aggregate Size Fractions Under the Hawaiian Fern Dicranopteris and Angiosperm Cheirodendrom

NASA Astrophysics Data System (ADS)

Stewart, C. E.; Amatangelo, K.; Neff, J.

2007-12-01

Soil organic matter (SOM) inherits much of its chemical nature from the dominant vegetation, including phenolic (lignin-derived), aromatic, and aliphatic (cutin and wax-derived) compounds. However, relatively stable recalcitrant compounds may also be formed as a result of condensation and complexation reactions through decomposition and protected with association with mineral particles. The Hawaiian fern species Dicranopteris decomposes more slowly than the angiosperm, Cheirodendrom due to high concentrations of recalcitrant C compounds. These aliphatic fern leaf waxes are well-preserved and may comprise a large portion of the recalcitrant organic matter in these soils. Our objective was to determine the chemical composition of the SOM under the O- (litter-dominated) and the A- (mineral) horizons formed under fern and angiosperm vegetation. To determine the effect of mineral-association, we fractioned the soil into four size classes; 850-590 μm, 590-180 μm, 180-53 μm and <53 μm and characterized the SOM via pyrolysis-gas chromatography-mass spectrometry (py-GC/MS). As the soils developed from the O- to the A-horizon, there was a decrease of lignin-derived phenolic compounds and an increase in more recalcitrant, aromatic and aliphatic C. Soils under ferns had greater relative concentrations of phenolic compounds, while the angiosperms had greater concentrations of fatty-acid methyl esters and furans (some polysaccharide-derived). Differences between size fractions were most evident in the O-horizon of both species. Recalcitrant fern-derived cutin and leaf waxes (alkene and alkanes structures) occurred in the 180-53 μm fraction, which has been shown to be the most stable of the aggregate-size fractions. Soils developed under fern versus angiosperm vegetation have distinct chemical signatures, which likely determine the recalcitrance of the SOM.

Fern rhizomes as fodder in Norway.

PubMed

Alm, Torbjørn

2016-09-06

Although ferns are often known under collective names in Norway, e.g. blom, a substantial number of vernacular names for individual fern species are known, in particular for useful or poisonous taxa. In the past, the rhizomes (Norwegian: moldfôr) of selected species were collected for fodder. Only scattered records of such use are available from southern Norway, and the tradition's core area is found in the two North Norwegian counties of Nordland and Troms, in accordance with the longer winters encountered in the north, frequently leading to fodder shortage in early spring. The tradition extends northeastwards into Finnmark, but is less well documented there. Although numerous sources mention the use of fern rhizomes for fodder, the fern species hiding behind the tradition are incompletely known. This paper aims at reviewing available data in terms of identifyng the species used for fodder, the history and geographical distribution of such use, and other relevant traditions, e.g. the timing and mode of collection, and the way the rhizomes were used. The study is based on data extracted from a variety of archival and literature sources; the latter retrived from my database of more than 7500 publications providing information on plant names and plant uses in Norway. More than 200 individual records mention the use of fern rhizomes for fodder in Norway. Only a fraction of these, typically made by botanist recording data on plant uses, provides information on the identity of the species used. Based on these, Dryopteris filix-mas and Matteuccia struthiopteris stand out as the most important species serving as sources of fern rhizomes for fodder. Locally, Dryopteris expansa was the preferred species, and this taxon may to some extent be overlooked in the records so far available. With a few exceptions, Norwegian folk tradition singles out Athyrium filix-femina as a harmful and poisonous species, causing livestock to go blind and lame, but whether this is true or not, remains unknown; the symptoms are in fact documented elsewhere as a consequence of poisoning due to Dryopteris filix-mas. In coastal north Norway, fern rhizomes were regularly collected for fodder, both in late autumn and early spring, and used to remedy a recurrent shortage of fodder in late winter and spring. Locally, the tradition of collecting fern rhizomes lived on until the 1940's or 1950's. Although mainly a tradition of the ethnic Norwegians, it had also been adopted by the farmers belonging to the Finnish and Sámi ethnic minorities. Fern rhizomes have a long tradition as an additional fodder for livestock in Norway. Preferred species were Matteuccia struthiopteris and Dryopteris filix-mas, locally also Dryopteris expansa. Athyrium filix-femina was considered to be poisonous, and usually avoided.

Cultural Resource Investigations in the L’Anguille River Basin, Lee, St. Francis, Cross and Poinsett Counties, Arkansas.

DTIC Science & Technology

1989-01-01

Paleovegetational Record, Hood Lake, Poinsett County, Arkansas Pollen Diagram: Trees, Shrubs , and Vines . 20 Figure 7. Terminal Pleistocene/Holocene Paleovegetational...herbs and shrubs , as well as low percentages of vines (lianas), ferns, and fern allies. Among the herbs, sedge pollen rose from 5% to a peak of 25%, and...Rhus copallinum). The nonwoody complement of plants contained moderate abundances of shrubs , vines , herbs, and ferns (Figure 7). The life-form group of

Graffiti and Art Education: "They Don't Understand How I Feel about the FUNK"

ERIC Educational Resources Information Center

Hampton, Rosalind

2013-01-01

On the morning of October 31, 2010, three adolescents were killed by a rail Passenger train in Montreal, Canada, in a well-known area for Graffiti writers to paint. The engineer did not see five boys walking on the tracks and the children did not hear or see the train coming. 17-year-olds Dylan Ford, Ricardo Conesa, and Mitch Bracken-Guenet lost…

An EM System With Dramatic Multi-Axis Transmitter and Tensor Gradiometer Receiver

DTIC Science & Technology

2011-06-01

Thus, the main difference between the spatial behavior of target anomalies measured with a magnetometer and those we measured with an EM system is in...current efforts include the development of tensor magnetic gradiometers based on triaxial fluxgate technology by the USGS (Snyder & Bracken, Development...Superconducting gradiometer/ Magnetometer Arrays and a Novel Signal Processing Technique. IEEE Trans. on Magnetics, MAG-11(2), 701-707. EM Tensor Gradiometer

International Violence Against Women: U.S. Response and Policy Issues

DTIC Science & Technology

2008-06-03

violence Adolescence Dating and courtship violence; economically coerced sex; sexual abuse in the workplace; rape; sexual harassment; forced...and Social Isolation of Married Adolescent Girls,” by Nicole Haberland, Erica Chong, Hillary Bracken, The Population Council, July 2004, p. 5. 33...child and adolescent marriage, which is particularly prevalent in parts of the Middle East and Africa, to be a form of violence against women. In such

Characteristics of the first child predict the parents' probability of having another child.

PubMed

Jokela, Markus

2010-07-01

In a sample of 7,695 families in the prospective, nationally representative British Millennium Cohort Study, this study examined whether characteristics of the 1st-born child predicted parents' timing and probability of having another child within 5 years after the 1st child's birth. Infant temperament was assessed with the Carey Infant Temperament Scale (Carey, 1972; Carey & McDevitt, 1978) at age 9 months, childhood socioemotional and behavioral characteristics with the Strengths and Difficulties Questionnaire (Goodman, 2001), and childhood cognitive ability with the Bracken School Readiness Assessment (Bracken, 2002) test at age 3 years. Survival analysis modeling indicated that the 1st child's low reactivity to novelty in infancy, high prosociality, low conduct problems, and high cognitive ability in childhood were associated with increased probability of parents having another child. Except for reactivity to novelty, these associations became stronger with time. High emotional symptoms were also positively associated with childbearing, but this was likely to reflect reverse causality-that is, the effect of sibling birth on the 1st child's adjustment. The results suggest that child effects, particularly those related to the child's cognitive ability, adaptability to novelty, and prosocial behavior, may be relevant to parents' future childbearing. (PsycINFO Database Record (c) 2010 APA, all rights reserved).

Structure and microanalysis of tear film ferning of camel tears, human tears, and Refresh Plus.

PubMed

Am, Masmali; Ra, Fagehi; El-Naggar, Ahmad H; Tm, Almubrad

2018-01-01

This study aimed to investigate the tear ferning pattern and chemical elements of the tear film of camel tears compared with human tears and Refresh Plus eye lubricant. Refresh Plus was used as a control because it provides a healthy ferning pattern, due to the presence of an optimum ratio of carboxymethylcellulose (CMC) sodium and electrolytes. The main research focus is elucidating the viability of camel tear film in the dry, harsh environment of the desert. The tears were collected from five camels, five male desert workers (20-25 years old) at a small village located 100 km from Riyadh, Saudi Arabia, and five male subjects (20-25 years old) from Riyadh. A small drop (1 μl) of tears was dried on a glass slide and observed under a light (Olympus BX1) and scanning electron microscope (Inspect S50, Field Electron and Ion Company [FEI]). Energy-dispersive X-ray spectroscopy (EDS) of the tear film and Refresh Plus were investigated with a JEOL 1400 scanning transmission electron microscope. The camel tear film pattern was surrounded by thick, peripheral, homogenous layers containing small oily droplets, particles, and tiny branches in the tear ferning. The tear ferning of the camel was grade 0-1, whereas the tear ferning of human tears and Refresh Plus was grade 1-2. The mass percentage of chloride was highest in the camel tears. The mass percentage of potassium in the camel tears was greater than that in the human tears, but it was less than that in the Refresh Plus lubricant. Camel tears exhibit a better quality than human tears and Refresh Plus lubricant do. The presence of oily droplet-like structures at the periphery of tear ferning suggests that camel tear film may have a higher quality and quantity of minerals and lubricants, which may help the animal to avoid eye dryness. Future work is required to investigate the identification of the elements present in the peripheral and central part of the tear ferning.

Effect of soil texture on phytoremediation of arsenic-contaminated soils

NASA Astrophysics Data System (ADS)

Pallud, C. E.; Matzen, S. L.; Olson, A.

2015-12-01

Soil arsenic (As) contamination is a global problem, resulting in part from anthropogenic activities, including the use of arsenical pesticides and treated wood, mining, and irrigated agriculture. Phytoextraction using the hyperaccumulating fern Pteris vittata is a promising new technology to remediate soils with shallow arsenic contamination with minimal site disturbance. However, many challenges still lie ahead for a global application of phytoremediation. For example, remediation times using P. vittata are on the order of decades. In addition, most research on As phytoextraction with P. vittata has examined As removal from sandy soils, where As is more available, with little research focusing on As removal from clayey soils, where As is less available. The objective of this study is to determine the effects of soil texture and soil fertilization on As extraction by P. vittata, to optimize remediation efficiency and decrease remediation time under complex field conditions. A field study was established 2.5 years ago in an abandoned railroad grade contaminated with As (average 85.5 mg kg-1) with texture varying from sandy loam to silty clay loam. Organic N, inorganic N, organic P, inorganic P, and compost were applied to separate sub-plots; control ferns were grown in untreated soil. In a parallel greenhouse experiment, ferns were grown in sandy loam soil extracted from the field (180 mg As kg-1), with similar treatments as those used at the field site, plus a high phosphate treatment and treatments with arbuscular mycorrhizal fungi. In the field study, fern mortality was 24% higher in clayey soil than in sandy soil due to waterlogging, while As was primarily associated with sandy soil. Results from the sandy loam soil indicate that soil treatments did not significantly increase As phytoextraction, which was lower in phosphate-treated ferns than in control ferns, both in the field and greenhouse study. Under greenhouse conditions, ferns treated with organic N were largest and accumulated the most total As, while under field conditions, control and compost-treated ferns accumulated the most total As. Under greenhouse conditions, leaching appeared to account for most As removed from sandy loam soil. Results from a similar greenhouse study now underway in clayey soil will be discussed.

Stasis and convergence characterize morphological evolution in eupolypod II ferns.

PubMed

Sundue, Michael A; Rothfels, Carl J

2014-01-01

Patterns of morphological evolution at levels above family rank remain underexplored in the ferns. The present study seeks to address this gap through analysis of 79 morphological characters for 81 taxa, including representatives of all ten families of eupolypod II ferns. Recent molecular phylogenetic studies demonstrate that the evolution of the large eupolypod II clade (which includes nearly one-third of extant fern species) features unexpected patterns. The traditional 'athyrioid' ferns are scattered across the phylogeny despite their apparent morphological cohesiveness, and mixed among these seemingly conservative taxa are morphologically dissimilar groups that lack any obvious features uniting them with their relatives. Maximum-likelihood and maximum-parsimony character optimizations are used to determine characters that unite the seemingly disparate groups, and to test whether the polyphyly of the traditional athyrioid ferns is due to evolutionary stasis (symplesiomorphy) or convergent evolution. The major events in eupolypod II character evolution are reviewed, and character and character state concepts are reappraised, as a basis for further inquiries into fern morphology. Characters were scored from the literature, live plants and herbarium specimens, and optimized using maximum-parsimony and maximum-likelihood, onto a highly supported topology derived from maximum-likelihood and Bayesian analysis of molecular data. Phylogenetic signal of characters were tested for using randomization methods and fitdiscrete. The majority of character state changes within the eupolypod II phylogeny occur at the family level or above. Relative branch lengths for the morphological data resemble those from molecular data and fit an ancient rapid radiation model (long branches subtended by very short backbone internodes), with few characters uniting the morphologically disparate clades. The traditional athyrioid ferns were circumscribed based upon a combination of symplesiomorphic and homoplastic characters. Petiole vasculature consisting of two bundles is ancestral for eupolypods II and a synapomorphy for eupolypods II under deltran optimization. Sori restricted to one side of the vein defines the recently recognized clade comprising Rhachidosoraceae through Aspleniaceae, and sori present on both sides of the vein is a synapomorphy for the Athyriaceae sensu stricto. The results indicate that a chromosome base number of x =41 is synapomorphic for all eupolypods, a clade that includes over two-thirds of extant fern species. The integrated approach synthesizes morphological studies with current phylogenetic hypotheses and provides explicit statements of character evolution in the eupolypod II fern families. Strong character support is found for previously recognized clades, whereas few characters support previously unrecognized clades. Sorus position appears to be less complicated than previously hypothesized, and linear sori restricted to one side of the vein support the clade comprising Aspleniaceae, Diplaziopsidaceae, Hemidictyaceae and Rachidosoraceae - a lineage only recently identified. Despite x =41 being a frequent number among extant species, to our knowledge it has not previously been demonstrated as the ancestral state. This is the first synapomorphy proposed for the eupolypod clade, a lineage comprising 67 % of extant fern species. This study provides some of the first hypotheses of character evolution at the family level and above in light of recent phylogenetic results, and promotes further study in an area that remains open for original observation.

Stasis and convergence characterize morphological evolution in eupolypod II ferns

PubMed Central

Sundue, Michael A.; Rothfels, Carl J.

2014-01-01

Background and Aims Patterns of morphological evolution at levels above family rank remain underexplored in the ferns. The present study seeks to address this gap through analysis of 79 morphological characters for 81 taxa, including representatives of all ten families of eupolypod II ferns. Recent molecular phylogenetic studies demonstrate that the evolution of the large eupolypod II clade (which includes nearly one-third of extant fern species) features unexpected patterns. The traditional ‘athyrioid’ ferns are scattered across the phylogeny despite their apparent morphological cohesiveness, and mixed among these seemingly conservative taxa are morphologically dissimilar groups that lack any obvious features uniting them with their relatives. Maximum-likelihood and maximum-parsimony character optimizations are used to determine characters that unite the seemingly disparate groups, and to test whether the polyphyly of the traditional athyrioid ferns is due to evolutionary stasis (symplesiomorphy) or convergent evolution. The major events in eupolypod II character evolution are reviewed, and character and character state concepts are reappraised, as a basis for further inquiries into fern morphology. Methods Characters were scored from the literature, live plants and herbarium specimens, and optimized using maximum-parsimony and maximum-likelihood, onto a highly supported topology derived from maximum-likelihood and Bayesian analysis of molecular data. Phylogenetic signal of characters were tested for using randomization methods and fitdiscrete. Key Results The majority of character state changes within the eupolypod II phylogeny occur at the family level or above. Relative branch lengths for the morphological data resemble those from molecular data and fit an ancient rapid radiation model (long branches subtended by very short backbone internodes), with few characters uniting the morphologically disparate clades. The traditional athyrioid ferns were circumscribed based upon a combination of symplesiomorphic and homoplastic characters. Petiole vasculature consisting of two bundles is ancestral for eupolypods II and a synapomorphy for eupolypods II under deltran optimization. Sori restricted to one side of the vein defines the recently recognized clade comprising Rhachidosoraceae through Aspleniaceae, and sori present on both sides of the vein is a synapomorphy for the Athyriaceae sensu stricto. The results indicate that a chromosome base number of x =41 is synapomorphic for all eupolypods, a clade that includes over two-thirds of extant fern species. Conclusions The integrated approach synthesizes morphological studies with current phylogenetic hypotheses and provides explicit statements of character evolution in the eupolypod II fern families. Strong character support is found for previously recognized clades, whereas few characters support previously unrecognized clades. Sorus position appears to be less complicated than previously hypothesized, and linear sori restricted to one side of the vein support the clade comprising Aspleniaceae, Diplaziopsidaceae, Hemidictyaceae and Rachidosoraceae – a lineage only recently identified. Despite x =41 being a frequent number among extant species, to our knowledge it has not previously been demonstrated as the ancestral state. This is the first synapomorphy proposed for the eupolypod clade, a lineage comprising 67 % of extant fern species. This study provides some of the first hypotheses of character evolution at the family level and above in light of recent phylogenetic results, and promotes further study in an area that remains open for original observation. PMID:24197753

Effect of linear alkyl benzene sulfonate on germination of spores of the aquatic fern Ceratopteris thalictroides

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

Singh, J.; Devi, S.

1989-07-01

Validity of fern spore germination bioassays for the effects of environmental pollution was established by many researchers. Some workers studied the phytotoxicity of linear alkyl benzene sulfonate (LAS) on the spores of Diplazium esculentum and observed that LAS levels above 0.001% are toxic to fern spores. Water pollution due to synthetic detergents has been increasing continuously during the last few years due to their extensive use in domestic life, agriculture and industry. These detergents are among the most common pollutants responsible for water pollution. In view of this fact, the phytotoxicity of LAS on germination of an aquatic fern Ceratopterismore » thalictroides spores was studied. However, in these studies, only germination pattern was taken as index and no observations were made on the developmental stages.« less

Gene transfer from a parasitic flowering plant to a fern

PubMed Central

Davis, Charles C; Anderson, William R; Wurdack, Kenneth J

2005-01-01

The rattlesnake fern (Botrychium virginianum (L.) Sw.) is obligately mycotrophic and widely distributed across the northern hemisphere. Three mitochondrial gene regions place this species with other ferns in Ophioglossaceae, while two regions place it as a member of the largely parasitic angiosperm order Santalales (sandalwoods and mistletoes). These discordant phylogenetic placements suggest that part of the genome in B. virginianum was acquired by horizontal gene transfer (HGT), perhaps from root-parasitic Loranthaceae. These transgenes are restricted to B. virginianum and occur across the range of the species. Molecular and life-history traits indicate that the transfer preceded the global expansion of B. virginianum, and that the latter may have happened very rapidly. This is the first report of HGT from an angiosperm to a fern, through either direct parasitism or the mediation of interconnecting fungal symbionts. PMID:16191635

How early ferns became trees.

PubMed

Galtier, J; Hueber, F M

2001-09-22

A new anatomically preserved fern, discovered from the basalmost Carboniferous of Australia, shows a unique combination of very primitive anatomical characters (solid centrarch cauline protostele) with the elaboration of an original model of the arborescent habit. This plant possessed a false trunk composed of a repetitive branching system of very small stems, which established it as the oldest tree-fern known to date. The potential of this primitive zygopterid fern to produce such an unusual growth form-without real equivalent among living plants-is related to the possession of two kinds of roots that have complementary functional roles: (i) large roots produced by stems with immediate positive geotropism, strongly adapted to mechanical support and water uptake from the soil; and (ii) small roots borne either on large roots or on petiole bases for absorbing humidity inside the false trunk.

Edge effects on fern community in an Atlantic Forest remnant of Rio Formoso, PE, Brazil.

PubMed

Silva, I A A; Pereira, A F N; Barros, I C L

2011-05-01

We have investigated how edge effects influence the fern community of Jaguarão Forest (08º 35' 49" S and 35º 15' 39" W), located in the district of Rio Formoso, Pernambuco, Brazil. A comparative analysis was made of the interior and edge of the fragment of forest, regarding the richness, abundance and diversity of ferns in the two areas. Six plots of 10 × 20 m were chosen, three in each area. A total of 381 ferns were recorded, which were distributed among 25 species, 17 genera and 12 families. The two areas (edge and interior) were found to differ, with distinct relative air humidities and temperatures (p = 0.00254 and p = 0.00019, respectively). The interior showed higher diversity (t = 7.251 and p = 0.018) and richness (t = 6.379 and p = 0.023) than the edge area, but the same abundance (t = 1.728; p = 0.226) as the edge. Regarding the composition of the flora, it was clear that the interior is a habitat completely distinct from the edge with regard to the fern community, given that only one species, Adiantum petiolatum Desv., was common to both environments. It was concluded that the edge effect causes a decrease in richness and abundance of the fern species found in Jaguarão Forest, where the more sensitive species are being replaced by species that are tolerant to the disturbance caused by the creation of an edge.

Plastid Phylogenomics Resolve Deep Relationships among Eupolypod II Ferns with Rapid Radiation and Rate Heterogeneity

PubMed Central

Wei, Ran; Yan, Yue-Hong; Harris, AJ; Kang, Jong-Soo; Shen, Hui; Zhang, Xian-Chun

2017-01-01

Abstract The eupolypods II ferns represent a classic case of evolutionary radiation and, simultaneously, exhibit high substitution rate heterogeneity. These factors have been proposed to contribute to the contentious resolutions among clades within this fern group in multilocus phylogenetic studies. We investigated the deep phylogenetic relationships of eupolypod II ferns by sampling all major families and using 40 plastid genomes, or plastomes, of which 33 were newly sequenced with next-generation sequencing technology. We performed model-based analyses to evaluate the diversity of molecular evolutionary rates for these ferns. Our plastome data, with more than 26,000 informative characters, yielded good resolution for deep relationships within eupolypods II and unambiguously clarified the position of Rhachidosoraceae and the monophyly of Athyriaceae. Results of rate heterogeneity analysis revealed approximately 33 significant rate shifts in eupolypod II ferns, with the most heterogeneous rates (both accelerations and decelerations) occurring in two phylogenetically difficult lineages, that is, the Rhachidosoraceae–Aspleniaceae and Athyriaceae clades. These observations support the hypothesis that rate heterogeneity has previously constrained the deep phylogenetic resolution in eupolypods II. According to the plastome data, we propose that 14 chloroplast markers are particularly phylogenetically informative for eupolypods II both at the familial and generic levels. Our study demonstrates the power of a character-rich plastome data set and high-throughput sequencing for resolving the recalcitrant lineages, which have undergone rapid evolutionary radiation and dramatic changes in substitution rates. PMID:28854625

Azolla domestication towards a biobased economy?

PubMed

Brouwer, Paul; Bräutigam, Andrea; Külahoglu, Canan; Tazelaar, Anne O E; Kurz, Samantha; Nierop, Klaas G J; van der Werf, Adrie; Weber, Andreas P M; Schluepmann, Henriette

2014-05-01

Due to its phenomenal growth requiring neither nitrogen fertilizer nor arable land and its biomass composition, the mosquito fern Azolla is a candidate crop to yield food, fuels and chemicals sustainably. To advance Azolla domestication, we research its dissemination, storage and transcriptome. Methods for dissemination, cross-fertilization and cryopreservation of the symbiosis Azolla filiculoides-Nostoc azollae are tested based on the fern spores. To study molecular processes in Azolla including spore induction, a database of 37 649 unigenes from RNAseq of microsporocarps, megasporocarps and sporophytes was assembled, then validated. Spores obtained year-round germinated in vitro within 26 d. In vitro fertilization rates reached 25%. Cryopreservation permitted storage for at least 7 months. The unigene database entirely covered central metabolism and to a large degree covered cellular processes and regulatory networks. Analysis of genes engaged in transition to sexual reproduction revealed a FLOWERING LOCUS T-like protein in ferns with special features induced in sporulating Azolla fronds. Although domestication of a fern-cyanobacteria symbiosis may seem a daunting task, we conclude that the time is ripe and that results generated will serve to more widely access biochemicals in fern biomass for a biobased economy. No claim to original European Union works. New Phytologist © 2014 New Phytologist Trust.

Reconciling extreme branch length differences: decoupling time and rate through the evolutionary history of filmy ferns.

PubMed

Schuettpelz, Eric; Pryer, Kathleen M

2006-06-01

The rate of molecular evolution is not constant across the Tree of Life. Characterizing rate discrepancies and evaluating the relative roles of time and rate along branches through the past are both critical to a full understanding of evolutionary history. In this study, we explore the interactions of time and rate in filmy ferns (Hymenophyllaceae), a lineage with extreme branch length differences between the two major clades. We test for the presence of significant rate discrepancies within and between these clades, and we separate time and rate across the filmy fern phylogeny to simultaneously yield an evolutionary time scale of filmy fern diversification and reconstructions of ancestral rates of molecular evolution. Our results indicate that the branch length disparity observed between the major lineages of filmy ferns is indeed due to a significant difference in molecular evolutionary rate. The estimation of divergence times reveals that the timing of crown group diversification was not concurrent for the two lineages, and the reconstruction of ancestral rates of molecular evolution points to a substantial rate deceleration in one of the clades. Further analysis suggests that this may be due to a genome-wide deceleration in the rate of nucleotide substitution.

FERN - a Java framework for stochastic simulation and evaluation of reaction networks.

PubMed

Erhard, Florian; Friedel, Caroline C; Zimmer, Ralf

2008-08-29

Stochastic simulation can be used to illustrate the development of biological systems over time and the stochastic nature of these processes. Currently available programs for stochastic simulation, however, are limited in that they either a) do not provide the most efficient simulation algorithms and are difficult to extend, b) cannot be easily integrated into other applications or c) do not allow to monitor and intervene during the simulation process in an easy and intuitive way. Thus, in order to use stochastic simulation in innovative high-level modeling and analysis approaches more flexible tools are necessary. In this article, we present FERN (Framework for Evaluation of Reaction Networks), a Java framework for the efficient simulation of chemical reaction networks. FERN is subdivided into three layers for network representation, simulation and visualization of the simulation results each of which can be easily extended. It provides efficient and accurate state-of-the-art stochastic simulation algorithms for well-mixed chemical systems and a powerful observer system, which makes it possible to track and control the simulation progress on every level. To illustrate how FERN can be easily integrated into other systems biology applications, plugins to Cytoscape and CellDesigner are included. These plugins make it possible to run simulations and to observe the simulation progress in a reaction network in real-time from within the Cytoscape or CellDesigner environment. FERN addresses shortcomings of currently available stochastic simulation programs in several ways. First, it provides a broad range of efficient and accurate algorithms both for exact and approximate stochastic simulation and a simple interface for extending to new algorithms. FERN's implementations are considerably faster than the C implementations of gillespie2 or the Java implementations of ISBJava. Second, it can be used in a straightforward way both as a stand-alone program and within new systems biology applications. Finally, complex scenarios requiring intervention during the simulation progress can be modelled easily with FERN.

Transcriptome-Mining for Single-Copy Nuclear Markers in Ferns

PubMed Central

Rothfels, Carl J.; Larsson, Anders; Li, Fay-Wei; Sigel, Erin M.; Huiet, Layne; Burge, Dylan O.; Ruhsam, Markus; Graham, Sean W.; Stevenson, Dennis W.; Wong, Gane Ka-Shu; Korall, Petra; Pryer, Kathleen M.

2013-01-01

Background Molecular phylogenetic investigations have revolutionized our understanding of the evolutionary history of ferns—the second-most species-rich major group of vascular plants, and the sister clade to seed plants. The general absence of genomic resources available for this important group of plants, however, has resulted in the strong dependence of these studies on plastid data; nuclear or mitochondrial data have been rarely used. In this study, we utilize transcriptome data to design primers for nuclear markers for use in studies of fern evolutionary biology, and demonstrate the utility of these markers across the largest order of ferns, the Polypodiales. Principal Findings We present 20 novel single-copy nuclear regions, across 10 distinct protein-coding genes: ApPEFP_C, cryptochrome 2, cryptochrome 4, DET1, gapCpSh, IBR3, pgiC, SQD1, TPLATE, and transducin. These loci, individually and in combination, show strong resolving power across the Polypodiales phylogeny, and are readily amplified and sequenced from our genomic DNA test set (from 15 diploid Polypodiales species). For each region, we also present transcriptome alignments of the focal locus and related paralogs—curated broadly across ferns—that will allow researchers to develop their own primer sets for fern taxa outside of the Polypodiales. Analyses of sequence data generated from our genomic DNA test set reveal strong effects of partitioning schemes on support levels and, to a much lesser extent, on topology. A model partitioned by codon position is strongly favored, and analyses of the combined data yield a Polypodiales phylogeny that is well-supported and consistent with earlier studies of this group. Conclusions The 20 single-copy regions presented here more than triple the single-copy nuclear regions available for use in ferns. They provide a much-needed opportunity to assess plastid-derived hypotheses of relationships within the ferns, and increase our capacity to explore aspects of fern evolution previously unavailable to scientific investigation. PMID:24116189

Fern Biology in Mexico - (A Class Field Program)

ERIC Educational Resources Information Center

Tryon, Rolla; And Others

1973-01-01

Organized field trips in the tropics proved to be an effective way to gather new information about ferns. The areas of study covered were: systematics and ecology, cytology and gametophyte structure, and morphogenesis and physiology. (PS)

Identifying potential habitat for the endangered Aleutian shield fern using topographical characteristics

USGS Publications Warehouse

Duarte, Adam; Wolcott, Daniel M.; Chow, T. Edwin

2012-01-01

The Aleutian shield fern Polystichum aleuticum is endemic to the Aleutian archipelago of Alaska and is listed as endangered pursuant to the U.S. Endangered Species Act. Despite numerous efforts to discover new populations of this species, only four known populations are documented to date, and information is needed to prioritize locations for future surveys. Therefore, we incorporated topographical habitat characteristics (elevation, slope, aspect, distance from coastline, and anthropogenic footprint) found at known Aleutian shield fern locations into a Geographical Information System (GIS) model to create a habitat suitability map for the entirety of the Andreaonof Islands. A total of 18 islands contained 489.26 km2 of highly suitable and moderately suitable habitat when weighting each factor equally. This study reports a habitat suitability map for the endangered Aleutian shield fern using topographical characteristics, which can be used to assist current and future recovery efforts for the species.

Chemotaxonomy for naturally macerated tree-fern cuticles (Medullosales and Marattiales), Carboniferous Sydney and Mabou Sub-Basins, Nova Scotia, Canada

USGS Publications Warehouse

Zodrow, E.L.; Mastalerz, Maria

2001-01-01

Naturally macerated cuticles (NMC) and one synangium, representing medullosalean and marattialean tree-fern species, from two Carboniferous coalfields in Nova Scotia, Canada, are investigated. The samples were analyzed by infrared spectroscopy (FTIR), and by pyrolysis-gas chromatograph/mass spectrometry (py-Gc/Ms) techniques in search for chemical signatures that would help in developing a chemotaxonomic classification of Carboniferous fern species, assuming genetically dependent make-up of cuticles. FTIR-derived CH2/CH3 ratios, in conjunction with contributions from carboxyl groups, demonstrated a better potential for discriminating between medullosalean genera and species than molecular signatures obtained by py-Gc/Ms. However, the latter provided better data for differentiating medullosalean from marattialean tree ferns as a group. Changes in the chemical make-up of naturally macerated cuticles due to sample preparation are discussed. ?? 2001 Elsevier Science B.V. All rights reserved.

New cyathealean tree ferns from the Cretaceous of South Africa: Natalipteris wildei gen. et sp. nov. and Kwazulupteris schaarschmidtii gen. et sp. nov.

NASA Astrophysics Data System (ADS)

Vera, Ezequiel Ignacio; Herbst, Rafael

2015-01-01

Two new genera and species of permineralized tree ferns, Natalipteris wildei and Kwazulupteris schaarschmidtii, are defined and described in detail. Natalipteris wildei is a solenostelic stem without well-developed sclerenchyma sheaths in their vascular strands, and has a single vascular strand in the petiole bases, which are somewhat similar to the one present in Cibotium and Nishidacaulis. On the other hand, K. schaarschmidtii is a dictyostelic fern, with petiole bases with fused adaxial arcs and a single isolated meristele in the petiolar pith. Both taxa present features that preclude their placement in the recognized families of Cyatheales, but may be referred to the "core tree ferns" clade. Fossil specimens were found in the Senckenberg Forschungsinstitut Palaeobotanical Collection and, although they lack precise stratigraphic provenance, it is suggested that they were collected from the Mzinene Formation (Albian-Turonian).

Unique expression of a sporophytic character on the gametophytes of notholaenid ferns (Pteridaceae).

PubMed

Johnson, Anne K; Rothfels, Carl J; Windham, Michael D; Pryer, Kathleen M

2012-06-01

Not all ferns grow in moist, shaded habitats; some lineages thrive in exposed, seasonally dry environments. Notholaenids are a clade of xeric-adapted ferns commonly characterized by the presence of a waxy exudate, called farina, on the undersides of their leaves. Although some other lineages of cheilanthoid ferns also have farinose sporophytes, previous studies suggested that notholaenids are unique in also producing farina on their gametophytes. For this reason, consistent farina expression across life cycle phases has been proposed as a potential synapomorphy for the genus Notholaena. Recent phylogenetic studies have shown two species with nonfarinose sporophytes to be nested within Notholaena, with a third nonfarinose species well supported as sister to all other notholaenids. This finding raises the question: are the gametophytes of these three species farinose like those of their close relatives, or are they glabrous, consistent with their sporophytes? We sowed spores of a diversity of cheilanthoid ferns onto culture media to observe and document whether their gametophytes produced farina. To place these species within a phylogenetic context, we extracted genomic DNA, then amplified and sequenced three plastid loci. The aligned data were analyzed using maximum likelihood to generate a phylogenetic tree. Here we show that notholaenids lacking sporophytic farina also lack farina in the gametophytic phase, and notholaenids with sporophytic farina always display gametophytic farina (with a single exception). Outgroup taxa never displayed gametophytic farina, regardless of whether they displayed farina on their sporophytes. Notholaenids are unique among ferns in consistently expressing farina across both phases of the life cycle.

Evidence for a Cenozoic radiation of ferns in an angiosperm-dominated canopy

PubMed Central

Schuettpelz, Eric; Pryer, Kathleen M.

2009-01-01

In today's angiosperm-dominated terrestrial ecosystems, leptosporangiate ferns are truly exceptional—accounting for 80% of the ≈11,000 nonflowering vascular plant species. Recent studies have shown that this remarkable diversity is mostly the result of a major leptosporangiate radiation beginning in the Cretaceous, following the rise of angiosperms. This pattern is suggestive of an ecological opportunistic response, with the proliferation of flowering plants across the landscape resulting in the formation of many new niches—both on forest floors and within forest canopies—into which leptosporangiate ferns could diversify. At present, one-third of leptosporangiate species grow as epiphytes in the canopies of angiosperm-dominated tropical rain forests. However, we know too little about the evolutionary history of epiphytic ferns to assess whether or not their diversification was in fact linked to the establishment of these forests, as would be predicted by the ecological opportunistic response hypothesis. Here we provide new insight into leptosporangiate diversification and the evolution of epiphytism by integrating a 400-taxon molecular dataset with an expanded set of fossil age constraints. We find evidence for a burst of fern diversification in the Cenozoic, apparently driven by the evolution of epiphytism. Whether this explosive radiation was triggered simply by the establishment of modern angiosperm-dominated tropical rain forest canopies, or spurred on by some other large-scale extrinsic factor (e.g., climate change) remains to be determined. In either case, it is clear that in both the Cretaceous and Cenozoic, leptosporangiate ferns were adept at exploiting newly created niches in angiosperm-dominated ecosystems. PMID:19567832

Evidence for a Cenozoic radiation of ferns in an angiosperm-dominated canopy.

PubMed

Schuettpelz, Eric; Pryer, Kathleen M

2009-07-07

In today's angiosperm-dominated terrestrial ecosystems, leptosporangiate ferns are truly exceptional--accounting for 80% of the approximately 11,000 nonflowering vascular plant species. Recent studies have shown that this remarkable diversity is mostly the result of a major leptosporangiate radiation beginning in the Cretaceous, following the rise of angiosperms. This pattern is suggestive of an ecological opportunistic response, with the proliferation of flowering plants across the landscape resulting in the formation of many new niches--both on forest floors and within forest canopies--into which leptosporangiate ferns could diversify. At present, one-third of leptosporangiate species grow as epiphytes in the canopies of angiosperm-dominated tropical rain forests. However, we know too little about the evolutionary history of epiphytic ferns to assess whether or not their diversification was in fact linked to the establishment of these forests, as would be predicted by the ecological opportunistic response hypothesis. Here we provide new insight into leptosporangiate diversification and the evolution of epiphytism by integrating a 400-taxon molecular dataset with an expanded set of fossil age constraints. We find evidence for a burst of fern diversification in the Cenozoic, apparently driven by the evolution of epiphytism. Whether this explosive radiation was triggered simply by the establishment of modern angiosperm-dominated tropical rain forest canopies, or spurred on by some other large-scale extrinsic factor (e.g., climate change) remains to be determined. In either case, it is clear that in both the Cretaceous and Cenozoic, leptosporangiate ferns were adept at exploiting newly created niches in angiosperm-dominated ecosystems.

Genetics Home Reference: alpha-1 antitrypsin deficiency

MedlinePlus

... 27(3):274-81. Review. Citation on PubMed de Serres FJ, Blanco I, Fernández-Bustillo E. Estimated ... 9. Epub 2006 Sep 27. Citation on PubMed de Serres FJ, Blanco I, Fernández-Bustillo E. Estimating ...

Nectar secretion on fern fronds associated with lower levels of herbivore damage: field experiments with a widespread epiphyte of Mexican cloud forest remnants

PubMed Central

Koptur, Suzanne; Palacios-Rios, Mónica; Díaz-Castelazo, Cecilia; Mackay, William P.; Rico-Gray, Víctor

2013-01-01

Background and Aims The oldest group of plants in which nectar secretions have been observed are the Polypodiopsida (ferns sensu lato). Nectaries have been reported in a dozen extant genera. The function of these nectaries has been investigated in several fern species, and in some circumstances has been demonstrated to have an antiherbivore role, attracting and maintaining biotic defence (ants and/or other predatory arthropods). This study documents foliar nectaries in Pleopeltis crassinervata, a widespread Central American epiphyte growing on a variety of trees in cloud forest areas of Veracruz, Mexico. This is a new record for this genus and species. Methods As previous experimental work on epiphytic species of Polypodium has demonstrated a protective role of ants for developing fronds, we conducted similar experiments (using nylon nail polish to cover nectaries rather than excluding ants with bands of sticky resin as in earlier work). The fronds of Pl. crassinervata developed over 6 weeks, at which time damage was assessed. The experiment was simultaneously conducted on a sympatric species lacking nectaries, Polypodium furfuraceum. Herbivore placement experiments were conducted with large and small caterpillars on both of these ferns. Key Results Fronds with nectaries covered suffered greater damage from herbivores over the course of their development, compared with fronds that had uncovered nectaries functioning normally. The parallel experiment on Po. furfuraceum showed no difference between manipulated and control fronds. Six species of ants (Brachymyrmex minutus, Crematogaster formosa, Paratrechina longicornis, Solenopsis geminata, S. picea and Wasmannia auropunctata) were observed visiting nectaries of Pl. crassinervata; most were effective in removing herbivore larvae placed on the fronds. Conclusions The long evolutionary history of ferns may explain why some previous studies of fern nectaries have shown little or no benefit to ferns from nectary visitors, as any coevolved herbivores are those resistant to ant defence. The results suggest that ants protect Pl. crassinervata fronds against herbivory. The presence of nectaries, and the relationship with ants, may contribute to this fern's widespread occurrence and persistence in the face of disturbance, though many other factors also play a role. Ant defence may be more likely to benefit a widespread species of disturbed habitats that encounters a wide range of non-adapted herbivores. PMID:23609022

How Fern Creek Is Beating Goliath

ERIC Educational Resources Information Center

Donovan, Margaret; Galatowitsch, Patrick; Hefferin, Keri; Highland, Shanita

2013-01-01

The "David" is Fern Creek Elementary, a small urban school in Orlando, Florida, that serves an overwhelmingly disadvantaged student population. The "Goliaths" are the mountains of problems that many inner-city students face--poverty, homelessness, mobility, instability, limited parent involvement, and violent neighborhood…

Text to accompany slides/photographs of Lower Cretaceous pollen and spores in sediments from the Muirkirk clay pit (Prince Georges County, MD)

USGS Publications Warehouse

Robbins, Eleanora I.

1991-01-01

The pollen and spores found in clay beds at the Muirkirk clay pit are those of ferns and lycopods, seed ferns, shrubby conifers, bald cypress-type conifers, and tree-sized conifers. Some of the ferns and conifers have modern representatives which help interpret the vegetation of this site that bears Early Cretaceous dinosaur fossils. The plants, as well as the presence of algae, fungi, and mineral remains of bacteria, show that the site was once a wetland that developed on the clay floor of a waning oxbow lake.

In vitro digestibility of fern and gymnosperm foliage: implications for sauropod feeding ecology and diet selection.

PubMed

Hummel, Jürgen; Gee, Carole T; Südekum, Karl-Heinz; Sander, P Martin; Nogge, Gunther; Clauss, Marcus

2008-05-07

Sauropod dinosaurs, the dominant herbivores throughout the Jurassic, challenge general rules of large vertebrate herbivory. With body weights surpassing those of any other megaherbivore, they relied almost exclusively on pre-angiosperm plants such as gymnosperms, ferns and fern allies as food sources, plant groups that are generally believed to be of very low nutritional quality. However, the nutritive value of these taxa is virtually unknown, despite their importance in the reconstruction of the ecology of Mesozoic herbivores. Using a feed evaluation test for extant herbivores, we show that the energy content of horsetails and of certain conifers and ferns is at a level comparable to extant browse. Based on our experimental results, plants such as Equisetum, Araucaria, Ginkgo and Angiopteris would have formed a major part of sauropod diets, while cycads, tree ferns and podocarp conifers would have been poor sources of energy. Energy-rich but slow-fermenting Araucaria, which was globally distributed in the Jurassic, was probably targeted by giant, high-browsing sauropods with their presumably very long ingesta retention times. Our data make possible a more realistic calculation of the daily food intake of an individual sauropod and improve our understanding of how large herbivorous dinosaurs could have flourished in pre-angiosperm ecosystems.

In vitro digestibility of fern and gymnosperm foliage: implications for sauropod feeding ecology and diet selection

PubMed Central

Hummel, Jürgen; Gee, Carole T; Südekum, Karl-Heinz; Sander, P. Martin; Nogge, Gunther; Clauss, Marcus

2008-01-01

Sauropod dinosaurs, the dominant herbivores throughout the Jurassic, challenge general rules of large vertebrate herbivory. With body weights surpassing those of any other megaherbivore, they relied almost exclusively on pre-angiosperm plants such as gymnosperms, ferns and fern allies as food sources, plant groups that are generally believed to be of very low nutritional quality. However, the nutritive value of these taxa is virtually unknown, despite their importance in the reconstruction of the ecology of Mesozoic herbivores. Using a feed evaluation test for extant herbivores, we show that the energy content of horsetails and of certain conifers and ferns is at a level comparable to extant browse. Based on our experimental results, plants such as Equisetum, Araucaria, Ginkgo and Angiopteris would have formed a major part of sauropod diets, while cycads, tree ferns and podocarp conifers would have been poor sources of energy. Energy-rich but slow-fermenting Araucaria, which was globally distributed in the Jurassic, was probably targeted by giant, high-browsing sauropods with their presumably very long ingesta retention times. Our data make possible a more realistic calculation of the daily food intake of an individual sauropod and improve our understanding of how large herbivorous dinosaurs could have flourished in pre-angiosperm ecosystems. PMID:18252667

Cytokinin-induced promotion of root meristem size in the fern Azolla supports a shoot-like origin of euphyllophyte roots.

PubMed

de Vries, Jan; Fischer, Angela Melanie; Roettger, Mayo; Rommel, Sophie; Schluepmann, Henriette; Bräutigam, Andrea; Carlsbecker, Annelie; Gould, Sven Bernhard

2016-01-01

The phytohormones cytokinin and auxin orchestrate the root meristem development in angiosperms by determining embryonic bipolarity. Ferns, having the most basal euphyllophyte root, form neither bipolar embryos nor permanent embryonic primary roots but rather an adventitious root system. This raises the questions of how auxin and cytokinin govern fern root system architecture and whether this can tell us something about the origin of that root. Using Azolla filiculoides, we characterized the influence of IAA and zeatin on adventitious fern root meristems and vasculature by Nomarski microscopy. Simultaneously, RNAseq analyses, yielding 36,091 contigs, were used to uncover how the phytohormones affect root tip gene expression. We show that auxin restricts Azolla root meristem development, while cytokinin promotes it; it is the opposite effect of what is observed in Arabidopsis. Global gene expression profiling uncovered 145 genes significantly regulated by cytokinin or auxin, including cell wall modulators, cell division regulators and lateral root formation coordinators. Our data illuminate both evolution and development of fern roots. Promotion of meristem size through cytokinin supports the idea that root meristems of euphyllophytes evolved from shoot meristems. The foundation of these roots was laid in a postembryonically branching shoot system. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

Jasmonic and salicylic acid response in the fern Azolla filiculoides and its cyanobiont.

PubMed

de Vries, Sophie; de Vries, Jan; Teschke, Hendrik; von Dahlen, Janina K; Rose, Laura E; Gould, Sven B

2018-01-03

Plants sense and respond to microbes utilizing a multilayered signalling cascade. In seed plants, the phytohormones jasmonic and salicylic acid (JA and SA) are key denominators of how plants respond to certain microbes. Their interplay is especially well-known for tipping the scales in plants' strategies of dealing with phytopathogens. In non-angiosperm lineages, the interplay is less well understood, but current data indicate that it is intertwined to a lesser extent and the canonical JA/SA antagonism appears to be absent. Here, we used the water fern Azolla filiculoides to gain insights into the fern's JA/SA signalling and the molecular communication with its unique nitrogen fixing cyanobiont Nostoc azollae, which the fern inherits both during sexual and vegetative reproduction. By mining large-scale sequencing data, we demonstrate that Azolla has most of the genetic repertoire to produce and sense JA and SA. Using qRT-PCR on the identified biosynthesis and signalling marker genes, we show that Azolla is responsive to exogenously applied SA. Furthermore, exogenous SA application influenced the abundance and gene expression of Azolla's cyanobiont. Our data provide a framework for JA/SA signalling in ferns and suggest that SA might be involved in Azolla's communication with its vertically inherited cyanobiont. © 2018 John Wiley & Sons Ltd.

Biodiversity and spatial distribution of epiphytic ferns on Alsophila setosa Kaulf. (Cyatheaceae) caudices in Rio Grande do Sul, Brazil.

PubMed

Schmitt, J L; Windisch, P G

2010-08-01

The extractive exploitation of the tree fern Alsophila setosa Kaulf. alters forest formations and diminishes the availability of micro-habitat for epiphytes. A survey of epiphytic fern communities on A. setosa at 16 study sites in different forest formations in the State of Rio Grande do Sul, Brazil, documented the occurrence of 31 species representing 16 genera and six families. The greatest richness of species occurred in Polypodiaceae (39%) and in the genus Asplenium L. (22%). Habitual holoepiphyte was the predominant ecological category, representing 61% of the species. Similarity analysis demonstrated heterogeneity in the composition of the epiphytic ferns at the study sites and indicated that the vegetation type is not the main factor for floristic difference. The lowest total specific richness (5) was recorded for the seasonal deciduous forest site. The majority of the sites presented similar averages of phorophyte height and epiphyte richness per caudex. In 25% of the sites the height of the host plants presented significant correlation with specific richness. Considering that the majority of the epiphytes are habitual and that some of them occur exclusively or preferentially on tree ferns, the maintenance of these host plants in the vegetation is essential for the conservation of epiphytic species.

The impact of wood ants (Formica rufa) on the distribution and abundance of ground beetles (Coleoptera: Carabidae) in a Scots pine plantation.

PubMed

Hawes, C; Stewart, A; Evans, H

2002-05-01

The importance of wood ants (Formica rufa) in determining the community structure (defined as the relative abundance of component species) and small-scale distribution of carabids was examined in a mature Scots pine stand in the New Forest, southern England. Carabids and wood ants were sampled by pitfall trapping throughout the forest stand from March to September 1998. The abundance of individual carabid species were modelled using vegetation type (grass or bracken), litter depth and wood ant density as independent explanatory variables. Models were fitted using a maximum-likelihood method (GLIM v.3.77; Baker 1985) with the assumption of a Poisson distribution, using a log-link function. Areas of high wood ant density were characterised by low abundance and species richness of carabids and high percentage dominance by the most commonly sampled species, Abax parallelepipedus. The extent and type of vegetation cover was found to influence the distribution and abundance of certain carabid species but only in areas where the density of wood ants was low. Large-bodied species occurred more frequently in bracken-dominated patches where the litter layer was deeper and the density of potential prey items was higher. Wood ant density was found to be the most important determinant of carabid species abundance in the study site.

Using Roundup and Oust to control interfering understories in Allegheny hardwood stands

Treesearch

S.B. Horsley

1991-01-01

Allegheny hardwood stands in the Pennsylvania portion of the type frequently contain dense understories of undesirable species such as hayscented fern (Dennstaedtia punctilobula (Michx.) Moore), New York fern (Thelypteris noveboracensis L.), grasses and sedges (Carex spp.), striped maple (Acer...

Non-linear growth in tree ferns, Dicksonia antarctica and Cyathea australis

PubMed Central

Blair, David P.; Blanchard, Wade; Banks, Sam C.; Lindenmayer, David B.

2017-01-01

Tree ferns are an important structural component of forests in many countries. However, because their regeneration is often unrelated to major disturbances, their age is often difficult to determine. In addition, rates of growth may not be uniform, which further complicates attempts to determine their age. In this study, we measured 5 years of growth of Cyathea australis and Dicksonia antarctica after a large wildfire in 2009 in south-eastern Australia. We found growth rates of these two species were unaffected by aspect and elevation but slope had a minor effect with D. antarctica growing 0.3mm faster for each additional degree of slope. Geographic location influenced growth in both species by up to 12 – 14mm/yr. The most consistent factor influencing growth rate, however, was initial height at the time of the 2009 fire; a finding consistent in both species and all geographic locations. For both tree fern species, individuals that were taller at the commencement of the study had greater overall growth for the duration of the study. This effect did not decrease even among the tallest tree ferns in our study (up to 6 metres tall). Overall, Cyathea australis averaged 73 (± 22)mm/year of growth (± 1SD), with the rate increasing 5mm/yr per metre of additional height. Dicksonia antarctica averaged 33 (± 13)mm/year, increasing by 6mm/yr/m. Growth rates dependent on initial height were unexpected and we discuss possible reasons for this finding. Variable growth rates also suggest that common age estimation methods of dividing height by average growth rate are likely to underestimate the age of short tree ferns, while overestimating the age of tall tree ferns, particularly if they have been subject to a fire. PMID:28493884

Fern Spore Longevity in Saline Water: Can Sea Bottom Sediments Maintain a Viable Spore Bank?

PubMed Central

de Groot, G. Arjen; During, Heinjo

2013-01-01

Freshwater and marine sediments often harbor reservoirs of plant diaspores, from which germination and establishment may occur whenever the sediment falls dry. Therewith, they form valuable records of historical inter- and intraspecific diversity, and are increasingly exploited to facilitate diversity establishment in new or restored nature areas. Yet, while ferns may constitute a considerable part of a vegetation’s diversity and sediments are known to contain fern spores, little is known about their longevity, which may suffer from inundation and - in sea bottoms - salt stress. We tested the potential of ferns to establish from a sea or lake bottom, using experimental studies on spore survival and gametophyte formation, as well as a spore bank analysis on sediments from a former Dutch inland sea. Our experimental results revealed clear differences among species. For Asplenium scolopendrium and Gymnocarpium dryopteris, spore germination was not affected by inundated storage alone, but decreased with rising salt concentrations. In contrast, for Asplenium trichomanes subsp. quadrivalens germination decreased following inundation, but not in response to salt. Germination rates decreased with time of storage in saline water. Smaller and less viable gametophytes were produced when saline storage lasted for a year. Effects on germination and gametophyte development clearly differed among genotypes of A. scolopendrium. Spore bank analyses detected no viable spores in marine sediment layers. Only two very small gametophytes (identified as Thelypteris palustris via DNA barcoding) emerged from freshwater sediments. Both died before maturation. We conclude that marine, and likely even freshwater sediments, will generally be of little value for long-term storage of fern diversity. The development of any fern vegetation on a former sea floor will depend heavily on the deposition of spores onto the drained land by natural or artificial means of dispersal. PMID:24223951

Non-linear growth in tree ferns, Dicksonia antarctica and Cyathea australis.

PubMed

Blair, David P; Blanchard, Wade; Banks, Sam C; Lindenmayer, David B

2017-01-01

Tree ferns are an important structural component of forests in many countries. However, because their regeneration is often unrelated to major disturbances, their age is often difficult to determine. In addition, rates of growth may not be uniform, which further complicates attempts to determine their age. In this study, we measured 5 years of growth of Cyathea australis and Dicksonia antarctica after a large wildfire in 2009 in south-eastern Australia. We found growth rates of these two species were unaffected by aspect and elevation but slope had a minor effect with D. antarctica growing 0.3mm faster for each additional degree of slope. Geographic location influenced growth in both species by up to 12 - 14mm/yr. The most consistent factor influencing growth rate, however, was initial height at the time of the 2009 fire; a finding consistent in both species and all geographic locations. For both tree fern species, individuals that were taller at the commencement of the study had greater overall growth for the duration of the study. This effect did not decrease even among the tallest tree ferns in our study (up to 6 metres tall). Overall, Cyathea australis averaged 73 (± 22)mm/year of growth (± 1SD), with the rate increasing 5mm/yr per metre of additional height. Dicksonia antarctica averaged 33 (± 13)mm/year, increasing by 6mm/yr/m. Growth rates dependent on initial height were unexpected and we discuss possible reasons for this finding. Variable growth rates also suggest that common age estimation methods of dividing height by average growth rate are likely to underestimate the age of short tree ferns, while overestimating the age of tall tree ferns, particularly if they have been subject to a fire.

Host range and genetic relatedness of Colletotrichum acutatum isolates from fruit crops and leatherleaf fern in Florida.

PubMed

MacKenzie, S J; Peres, N A; Barquero, M P; Arauz, L F; Timmer, L W

2009-05-01

Isolates of Colletotrichum acutatum were collected from anthracnose-affected strawberry, leatherleaf fern, and Key lime; ripe-rot-affected blueberry; and postbloom fruit drop (PFD)-affected sweet orange in Florida. Additional isolates from ripe-rot-affected blueberry were collected from Georgia and North Carolina and from anthracnose-affected leatherleaf fern in Costa Rica. Pathogenicity tests on blueberry and strawberry fruit; foliage of Key lime, leatherleaf fern, and strawberry; and citrus flowers showed that isolates were highly pathogenic to their host of origin. Isolates were not pathogenic on foliage of heterologous hosts; however, several nonhomologous isolates were mildly or moderately pathogenic to citrus flowers and blueberry isolates were pathogenic to strawberry fruit. Based on sequence data from the internal transcribed spacer (ITS)1-5.8S rRNA-ITS2 region of the rDNA repeat, the glutaraldehyde-3-phosphate dehydrogenase intron 2 (G3PD), and the glutamine synthase intron 2 (GS), isolates from the same host were identical or very similar to each other and distinct from those isolated from other hosts. Isolates from leatherleaf fern in Florida were the only exception. Among these isolates, there were two distinct G3PD and GS sequences that occurred in three of four possible combinations. Only one of these combinations occurred in Costa Rica. Although maximum parsimony trees constructed from genomic regions individually displayed little or no homoplasy, there was a lack of concordance among genealogies that was consistent with a history of recombination. This lack of concordance was particularly evident within a clade containing PFD, Key lime, and leatherleaf fern isolates. Overall, the data indicated that it is unlikely that a pathogenic strain from one of the hosts examined would move to another of these hosts and produce an epidemic.

Variation of desiccation tolerance and longevity in fern spores

USDA-ARS?s Scientific Manuscript database

This work contributes to the understanding of plant cell responses to water stress when applied at different intensity and duration. Fern spores are used to explore survival at relative humidity (RH) < 85% because their unicellular nature eliminates complexities that may arise in multicellular orga...

Phototropic leaf movements and photosynthetic performance in an amphibious fern, Marsilea quadrifolia.

PubMed

Kao, Wen-Yuan; Lin, Bai-Ling

2010-09-01

Diurnal phototropism has not been reported in ferns. In this study we found that the four leaflets of the amphibious fern Marsilea quadrifolia are capable of adjusting their leaflet angle and leaflet azimuth in response to changes in the position of the sun's direct beam, exhibiting more diaphototropic movements (orienting the plane of the lamina perpendicular to incident light) in the morning and late afternoon, and more paraphototropic movements (orienting the plane of the lamina parallel to incident light) at noon. In addition, by cutting off the leaflet lamina and covering portions of leaflets with black tape, the junction between the leaflet and petiole was found to be responsible for light reception. Among the light spectrum investigated, blue light was the most effective at inducing diaphototropism. The role of diurnal phototropism in enhancing carbon return and ameliorating photoinhibition was also evaluated. It was concluded that diurnal phototropic leaf movement represents one of the plastic responses enabling this amphibious fern to grow under terrestrial conditions.

BiVO4 Fern Architectures: A Competitive Anode for Lithium-Ion Batteries.

PubMed

Dubal, Deepak P; Patil, Deepak R; Patil, Santosh S; Munirathnam, N R; Gomez-Romero, Pedro

2017-09-21

The development of high-performance anode materials for lithium-ion batteries (LIBs) is currently subject to much interest. In this study, BiVO 4 fern architectures are introduced as a new anode material for LIBs. The BiVO 4 fern shows an excellent reversible capacity of 769 mAh g -1 (ultrahigh volumetric capacity of 3984 mAh cm -3 ) at 0.12 A g -1 with large capacity retention. A LIB full cell is then assembled with a BiVO 4 fern anode and LiFePO 4 (LFP, commercial) as cathode material. The device can achieve a capacity of 140 mAh g -1 at 1C rate, that is, 81 % of the capacity of the cathode and maintained to 104 mAh g -1 at a high rate of 8C, which makes BiVO 4 a promising candidate as a high-energy anode material for LIBs. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Separating Active and Passive Influences on Stomatal Control of Transpiration[OPEN

PubMed Central

McAdam, Scott A.M.; Brodribb, Timothy J.

2014-01-01

Motivated by studies suggesting that the stomata of ferns and lycophytes do not conform to the standard active abscisic acid (ABA) -mediated stomatal control model, we examined stomatal behavior in a conifer species (Metasequoia glyptostroboides) that is phylogenetically midway between the fern and angiosperm clades. Similar to ferns, daytime stomatal closure in response to moderate water stress seemed to be a passive hydraulic process in M. glyptostroboides immediately alleviated by rehydrating excised shoots. Only after prolonged exposure to more extreme water stress did active ABA-mediated stomatal closure become important, because foliar ABA production was triggered after leaf turgor loss. The influence of foliar ABA on stomatal conductance and stomatal aperture was highly predictable and additive with the passive hydraulic influence. M. glyptostroboides thus occupies a stomatal behavior type intermediate between the passively controlled ferns and the characteristic ABA-dependent stomatal closure described in angiosperm herbs. These results highlight the importance of considering phylogeny as a major determinant of stomatal behavior. PMID:24488969

Separating active and passive influences on stomatal control of transpiration.

PubMed

McAdam, Scott A M; Brodribb, Timothy J

2014-04-01

Motivated by studies suggesting that the stomata of ferns and lycophytes do not conform to the standard active abscisic acid (ABA) -mediated stomatal control model, we examined stomatal behavior in a conifer species (Metasequoia glyptostroboides) that is phylogenetically midway between the fern and angiosperm clades. Similar to ferns, daytime stomatal closure in response to moderate water stress seemed to be a passive hydraulic process in M. glyptostroboides immediately alleviated by rehydrating excised shoots. Only after prolonged exposure to more extreme water stress did active ABA-mediated stomatal closure become important, because foliar ABA production was triggered after leaf turgor loss. The influence of foliar ABA on stomatal conductance and stomatal aperture was highly predictable and additive with the passive hydraulic influence. M. glyptostroboides thus occupies a stomatal behavior type intermediate between the passively controlled ferns and the characteristic ABA-dependent stomatal closure described in angiosperm herbs. These results highlight the importance of considering phylogeny as a major determinant of stomatal behavior.

Ants inhabiting myrmecophytic ferns regulate the distribution of lianas on emergent trees in a Bornean tropical rainforest.

PubMed

Tanaka, Hiroshi O; Itioka, Takao

2011-10-23

Little is known about the spatial distribution of lianas on emergent trees in tropical rainforests and the factors affecting this distribution. The present study investigated the effects of an arboreal ant species, Crematogaster difformis, which forms myrmecophytic symbioses with two epiphytic ferns, Lecanopteris sp. and Platycerium sp., on the spatial distribution of lianas associated with emergent trees. Living lianas were placed onto trunk surfaces inside and outside the territories of the ants in the canopy, to examine their ability to remove them. The number of leaves pruned by the ants was significantly higher on lianas inside than outside their territories. The spatial overlap of the distributions of lianas and the two ferns on emergent trees were then examined. The frequency of liana colonization of tree crowns was found to be significantly lower on trees with than without ferns. Under the natural conditions, C. difformis workers were observed biting and pruning the lianas. These results suggest that C. difformis regulates the distribution of lianas on emergent trees.

Sorption equilibrium of mercury onto ground-up tree fern.

PubMed

Ho, Yuh-Shan; Wang, Chung-Chi

2008-08-15

The sorption behavior of mercury at different temperatures onto ground-up tree fern was investigated. The experimental results were fitted to two two-parameter isotherms, the Freundlich and Langmuir isotherms, as well as to two three-parameter isotherms, the Redlich-Peterson and Sips isotherms to obtain the characteristic parameters of each model. A comparison of best-fitting was performed using the coefficient of determination and Chi-square test. Both the Langmuir and Redlich-Peterson isotherms were found to well represent the measured sorption data. According to the evaluation using the Langmuir equation, the saturated monolayer sorption capacity of mercury ions onto ground-up tree fern was 26.5 mg/g at 298 K. It was noted that an increase in temperature resulted in a higher mercury ion loading per unit weight of the tree fern. In addition, various thermodynamic parameters, such as DeltaG degrees, DeltaH degrees, and DeltaS degrees, were calculated and compared with the sorption of mercury by other sorbents.

Historical reconstruction of climatic and elevation preferences and the evolution of cloud forest-adapted tree ferns in Mesoamerica.

PubMed

Sosa, Victoria; Ornelas, Juan Francisco; Ramírez-Barahona, Santiago; Gándara, Etelvina

2016-01-01

Cloud forests, characterized by a persistent, frequent or seasonal low-level cloud cover and fragmented distribution, are one of the most threatened habitats, especially in the Neotropics. Tree ferns are among the most conspicuous elements in these forests, and ferns are restricted to regions in which minimum temperatures rarely drop below freezing and rainfall is high and evenly distributed around the year. Current phylogeographic data suggest that some of the cloud forest-adapted species remained in situ or expanded to the lowlands during glacial cycles and contracted allopatrically during the interglacials. Although the observed genetic signals of population size changes of cloud forest-adapted species including tree ferns correspond to predicted changes by Pleistocene climate change dynamics, the observed patterns of intraspecific lineage divergence showed temporal incongruence. Here we combined phylogenetic analyses, ancestral area reconstruction, and divergence time estimates with climatic and altitudinal data (environmental space) for phenotypic traits of tree fern species to make inferences about evolutionary processes in deep time. We used phylogenetic Bayesian inference and geographic and altitudinal distribution of tree ferns to investigate ancestral area and elevation and environmental preferences of Mesoamerican tree ferns. The phylogeny was then used to estimate divergence times and ask whether the ancestral area and elevation and environmental shifts were linked to climatic events and historical climatic preferences. Bayesian trees retrieved Cyathea, Alsophyla, Gymnosphaera and Sphaeropteris in monophyletic clades. Splits for species in these genera found in Mesoamerican cloud forests are recent, from the Neogene to the Quaternary, Australia was identified as the ancestral area for the clades of these genera, except for Gymnosphaera that was Mesoamerica. Climate tolerance was not divergent from hypothesized ancestors for the most significant variables or elevation. For elevational shifts, we found repeated change from low to high elevations. Our data suggest that representatives of Cyatheaceae main lineages migrated from Australia to Mesoamerican cloud forests in different times and have persisted in these environmentally unstable areas but extant species diverged recentrly from their ancestors.

Historical reconstruction of climatic and elevation preferences and the evolution of cloud forest-adapted tree ferns in Mesoamerica

PubMed Central

2016-01-01

Background Cloud forests, characterized by a persistent, frequent or seasonal low-level cloud cover and fragmented distribution, are one of the most threatened habitats, especially in the Neotropics. Tree ferns are among the most conspicuous elements in these forests, and ferns are restricted to regions in which minimum temperatures rarely drop below freezing and rainfall is high and evenly distributed around the year. Current phylogeographic data suggest that some of the cloud forest-adapted species remained in situ or expanded to the lowlands during glacial cycles and contracted allopatrically during the interglacials. Although the observed genetic signals of population size changes of cloud forest-adapted species including tree ferns correspond to predicted changes by Pleistocene climate change dynamics, the observed patterns of intraspecific lineage divergence showed temporal incongruence. Methods Here we combined phylogenetic analyses, ancestral area reconstruction, and divergence time estimates with climatic and altitudinal data (environmental space) for phenotypic traits of tree fern species to make inferences about evolutionary processes in deep time. We used phylogenetic Bayesian inference and geographic and altitudinal distribution of tree ferns to investigate ancestral area and elevation and environmental preferences of Mesoamerican tree ferns. The phylogeny was then used to estimate divergence times and ask whether the ancestral area and elevation and environmental shifts were linked to climatic events and historical climatic preferences. Results Bayesian trees retrieved Cyathea, Alsophyla, Gymnosphaera and Sphaeropteris in monophyletic clades. Splits for species in these genera found in Mesoamerican cloud forests are recent, from the Neogene to the Quaternary, Australia was identified as the ancestral area for the clades of these genera, except for Gymnosphaera that was Mesoamerica. Climate tolerance was not divergent from hypothesized ancestors for the most significant variables or elevation. For elevational shifts, we found repeated change from low to high elevations. Conclusions Our data suggest that representatives of Cyatheaceae main lineages migrated from Australia to Mesoamerican cloud forests in different times and have persisted in these environmentally unstable areas but extant species diverged recentrly from their ancestors. PMID:27896030

Phylogeny of Marsileaceous Ferns and Relationships of the Fossil Hydropteris pinnata Reconsidered.

PubMed

Pryer

1999-09-01

Recent phylogenetic studies have provided compelling evidence that confirms the once disputed hypothesis of monophyly for heterosporous leptosporangiate ferns (Marsileaceae and Salviniaceae). Hypotheses for relationships among the three genera of Marsileaceae (Marsilea, Regnellidium, and Pilularia), however, have continued to be in conflict. The phylogeny of Marsileaceae is investigated here using information from morphology and rbcL sequence data. In addition, relationships among all heterosporous ferns, including the whole-plant fossil Hydropteris pinnata are reconsidered. Data sets of 71 morphological and 1239 rbcL characters for 23 leptosporangiate ferns, including eight heterosporous ingroup taxa and 15 homosporous outgroup taxa, were subjected to maximum parsimony analysis. Morphological analyses were carried out both with and without the fossil Hydropteris, and it was excluded from all analyses with rbcL data. An annotated list of the 71 morphological characters is provided in the appendix. For comparative purposes, the Rothwell and Stockey (1994) data set was also reanalyzed here. The best estimate of phylogenetic relationships for Marsileaceae in all analyses is that Pilularia and Regnellidium are sister taxa and Marsilea is sister to that clade. Morphological synapomorphies for various nodes are discussed. Analyses that included Hydropteris resulted in two most-parsimonious trees that differ only in the placement of the fossil. One topology is identical to the relationship found by Rothwell and Stockey (1994), placing the fossil sister to the Azolla plus Salvinia clade. The alternative topology places Hydropteris as the most basal member of the heterosporous fern clade. Equivocal interpretations for character evolution in heterosporous ferns are discussed in the context of these two most-parsimonious trees. Because of the observed degree of character ambiguity, the phylogenetic placement of Hydropteris is best viewed as unresolved, and recognition of the suborder Hydropteridineae, as circumscribed by Rothwell and Stockey (1994), is regarded as premature. The two competing hypotheses of relationships for heterosporous ferns are also compared with the known temporal distribution of relevant taxa. Stratigraphic fit of the phylogenetic estimates is measured by using the Stratigraphic Consistency Index and by comparison with minimum divergence times.

Using a Microscale Approach to Rapidly Separate and Characterize Three Photosynthetic Pigment Species from Fern

ERIC Educational Resources Information Center

Ayudhya, Theppawut Israsena Na; Posey, Frederick T.; Tyus, Jessica C.; Dingra, Nin N.

2015-01-01

A rapid separation of three photosynthetic pigments (chlorophyll "a" and "b" and xanthophyll) from fern ("Polystichum acrostichoides") is described using microscale solvent extraction and traditional thin layer chromatography that minimizes use of harmful chemicals and lengthy procedures. The experiment introduces…

Cultural Resources Investigations of the West Bank Hurricane Protection Project, Jefferson Parish, Louisiana

DTIC Science & Technology

1989-09-01

most common understory plants include thistle (Carduus sp.), violet (Viola sp.), bur- marigold (Bidens laevis), and ferns. Drained cypress-tupelo swamp... marigold (Bidens laevis), violet (Viola sp.), thistle (Carduus sp.), and Southern shield fern (Thelypteris kunthil). Drained marsh makes up the

Do ferns and lycophytes function as medicinal plants? A study of their low representation in traditional pharmacopoeias.

PubMed

Reinaldo, Rafael Corrêa Prota dos Santos; Santiago, Augusto César Pessôa; Medeiros, Patrícia Muniz; Albuquerque, Ulysses Paulino

2015-12-04

Ethnobotany is becoming an important tool for understanding how traditional medical systems are organized and which variables affect their structure and dynamics. However, some phenomena observed in ethnobotanical studies led us to question whether such phenomena are real or methodological artifacts. The small proportion of ferns and lycophytes in ethnobotanical surveys of medicinal plants is one such phenomenon, and its causes should be identified using different approach levels. The present study aimed to clarify the reasons for a low representation of these two groups in studies of medicinal plants. The present study considered the following hypotheses: 1) ferns and lycophytes are little represented in different ethnobotanical studies because of inadequate data collection methods to record these species; 2) ferns and lycophytes are little represented because of the local perception of their low therapeutic efficacy; and 3) species of ferns and lycophytes are represented in local pharmacopoeias in proportion to the size of their families. We chose rural communities from Chapada do Araripe, Northeast Brazil to test our hypotheses. Data on the medicinal plant repertoires of the communities and on the perceived therapeutic efficacy of ferns were obtained using two different methods, semi-structured interviews associated with free lists and a checklist interview, both applied to local specialists. The resulting data were analyzed differently for each test. In addition, data regarding the total flora x medicinal flora ratio were obtained with a floristic survey and accessing data banks from previous studies performed by our research team. All hypotheses were confirmed, showing that all three factors contributed to the low representation of these plant groups as medicinal resources. The present study showed that free-list interviews are not a good method to access traditional knowledge of medicinal ferns and lycophytes and that the use of visual stimuli can help the memory of the informants, thus making it possible to associate the perceived characteristics with plant use. The results also showed that individuals perceive these plants as inferior therapeutic resources compared to angiosperms, which contributes to knowledge of their use not being transmitted. The final result of the present study was that the distribution of medicinal fern and lycophyte species within families was consistent with the total flora x medicinal flora ratio. This result indicates that even if the most appropriate data collection method was used for the ethnobotanical survey, the number of species would not be as expressive as that of angiosperms. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Medicinal Properties of Adiantum capillus-veneris Linn. in Traditional Medicine and Modern Phytotherapy: A Review Article

PubMed Central

DEHDARI, Sahar; HAJIMEHDIPOOR, Homa

2018-01-01

Background: Adiantum capillus-veneris Linn (Maidenhair fern) is an herb belonging to the family Pteridaceae. It is named as “Pare-siavashan” in medical and pharmaceutical textbooks of Iranian Traditional Medicine. The fronds of Maidenhair fern were mainly administrated by ancient physicians as single medicine or in combination with other plants in multi-herbal formulations for curing different diseases. Because of different chemical compositions, the herb fronds were also assessed for its numerous pharmacological effects. Therefore, the current study was done to review the traditional usage and modern pharmacological and toxicological effects of Maidenhair fern. Methods: Scientific databases and publications including Web of Science, PubMed, Scopus, Science direct, Cochrane Library, SID (for Persian papers) and medical and pharmaceutical textbooks of traditional medicine as well were searched for “Adiantum capillus-veneris”, “Maidenhair fern” and “Pare-siavashan” without limitation up to 2016. Results: Maidenhair fern exhibited to possess anti-diabetic, anticonvulsant, analgesic, hypocholesterolemic, goitrogenic, anti-thyroidal, antibacterial, antifungal, wound healing, antiobesity, anti hair loss, anti-asthmatic, anti-inflammatory, antidiarrheal and antispasmodic, antioxidant as well as diuretic, anti-urolithiatic and detoxifying effects in modern medicine. Ancient physicians declared some of the confirmed pharmacological effects. Conclusion: Maidenhair fern frond can be a good candidate for clinical purpose. Therefore, future researches on the other mentioned effects in traditional medicine are recommended. PMID:29445628

Effect of enhanced nitrogen input on release of nutrients and nutrient availability in stands of tall fern Athyrium distentifolium

NASA Astrophysics Data System (ADS)

Tå¯Ma, Ivan; Holuib, Petr; Záhora, Jaroslav; Fiala, Karel

2010-05-01

Improved light conditions, after destruction of tree canopy, soil acidification and increased nitrogen availability, support intensive spreading of acidophilous perennial grasses and stands of tall fern (Athyrium distentifolium) on deforested sites in the Moravian-Silesian Beskydy Mts. (the Czech Republic). The aim of the study was to determine how higher inputs of nitrogen affect the release of nutrients during decomposition processes of fern litter. The experimental site was chosen on a southwest-facing slope of the Kněhyně Mt. (49o31´ N, 18o 32´E, 1170 m a.s.l.) in the Moravian-Silesin Beskydy Mts. in the Czech Republic. The area is characterized by an annual mean air temperature of 5.6 oC and annual precipitation of 1110 mm. A large fern stand was divided in four blocks (5x3 m) and on two of them higher doses of nitrogen were applied (50 kgN/ha in five doses in the course of the growing season). Similarly, mesh-bags with fresh natural litter of fern were used to determine rate of litter decomposition during one year. Samples were inserted in both nitrogen treated and untreated fern stands in autumn 2006 and 2007 collected in autumn 2007 and 2008. On the basis of litter amount estimated at the start and at the end of exposure and of actual content of minerals in original and exposed litter, the release and/or accumulation of minerals during decomposition were calculated. The availability (more or less in the case of ammonia-nitrogen) and movement of percolated nitrogen (mainly in the case of nitrate-nitrogen) was estimated in situ by the trapping of mineral N into the ion exchange resin (IER) inserted into special cover. The decomposition rate of native A. distentifolium litter was approximately the same (29-30 %) at both nitrogen availability, however the element release from decomposed litter was higher for N, P and Ca in both years and for K and Mg in the first year as well. However, decomposition rate of cellulose was two times greater in fern stands than in adjacent spruce stands without ferns. The values are expressed as the captured mineral nitrogen into ion exchange resins exposed in situ. The availability of soil ammonia- as well as nitrate- nitrogen in control stockings, and after the addition of different sources (raw silk and cellulose) were, in general, not very different below fern plants and in the bare soils. It can be concluded, that the microbial competition for available nitrogen is very high after the addition of cellulose, which consequently restrict the rate of mineral nitrogen trapped into the ion exchange resin. In contrary higher amounts of captured mineral nitrogen were estimated after the addition of raw silk. This study was supported by GP AS CR (IAA 600050616) and the Research plan No. MSM6215648905, Ministry of Education, CR.

Installation Restoration Program. Phase 1. Records Search, Hazardous Materials Disposal Sites, Kirtland AFB, New Mexico

DTIC Science & Technology

1981-11-01

Additional ferns, including Eaton lip fern, occur on shady granite outcroppings. Reveechon three-awn, Scribner needlegrass, noseburn, bear grass, banana ...torrey rush, and smooth monkey flower are among the more obvious plants in this area. Arroyos and seasonally intermittent streams support other

Effects of arsenic on nitrogen metabolism in arsenic hyperaccumulator and non-hyperaccumulator ferns

USDA-ARS?s Scientific Manuscript database

This study investigated the effects of arsenic on the in vitro activities of the enzymes (nitrate reductase and nitrite reductase) involved in nitrate metabolism in the roots, rhizomes, and fronds of two four-month old fern plants, Pteris vittata, an arsenic-hyperaccumulator, and Pteris ensiformis, ...

The cyanobiont in an Azolla fern is neither Anabaena nor Nostoc.

PubMed

Baker, Judith A; Entsch, Barrie; McKay, David B

2003-12-05

The cyanobacterial symbionts in the fern Azolla have generally been ascribed to either the Anabaena or Nostoc genera. By using comparisons of the sequences of the phycocyanin intergenic spacer and a fragment of the 16S rRNA, we found that the cyanobiont from an Azolla belongs to neither of these genera.

Ants inhabiting myrmecophytic ferns regulate the distribution of lianas on emergent trees in a Bornean tropical rainforest

PubMed Central

Tanaka, Hiroshi O.; Itioka, Takao

2011-01-01

Little is known about the spatial distribution of lianas on emergent trees in tropical rainforests and the factors affecting this distribution. The present study investigated the effects of an arboreal ant species, Crematogaster difformis, which forms myrmecophytic symbioses with two epiphytic ferns, Lecanopteris sp. and Platycerium sp., on the spatial distribution of lianas associated with emergent trees. Living lianas were placed onto trunk surfaces inside and outside the territories of the ants in the canopy, to examine their ability to remove them. The number of leaves pruned by the ants was significantly higher on lianas inside than outside their territories. The spatial overlap of the distributions of lianas and the two ferns on emergent trees were then examined. The frequency of liana colonization of tree crowns was found to be significantly lower on trees with than without ferns. Under the natural conditions, C. difformis workers were observed biting and pruning the lianas. These results suggest that C. difformis regulates the distribution of lianas on emergent trees. PMID:21508025

Seedling mortality in Hawaiian rain forest: The role of small-scale physical disturbance

USGS Publications Warehouse

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

2001-01-01

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

Exposure and bioavailability of arsenic in contaminated soils from the La Parrilla mine, Spain

NASA Astrophysics Data System (ADS)

Anawar, H. M.; Garcia-Sanchez, A.; Murciego, A.; Buyolo, T.

2006-05-01

Arsenic derived from mining activity may contaminate water, soil and plant ecosystems resulting in human health and ecotoxicological risks. In this study, exposure assessment of arsenic (As) in soil, spoil, pondwater and plants collected from the areas contaminated by mine tailings and spoils in and around the La Parrilla mine, Caceres province, Spain, was carried out using AAS method. Water solubility, bioavailability and soil-plant transfer coefficients of As and phytoremediation potential of plants were determined. Arsenic concentrations varied from 148 to 2,540 mg/kg in soils of site 1 and from 610 to 1,285 mg/kg in site 2 exceeding the guideline limit for agricultural soil (50 mg/kg). Arsenic concentrations in pond waters varied from 8.8 to 101.4 μg/l. High concentrations of water-soluble As in the soils that ranged from 0.10 to 4.71 mg/kg in site 1 and from 0.46 to 4.75 mg/kg in site 2 exceeded the maximum permitted level of water-soluble As (0.04 mg/kg) in agricultural soils. Arsenic concentrations varied from 0.8 to 149.5 mg/kg dry wt in the plants of site 1 and from 2.0 to 10.0 mg/kg in the plants of site 2. Arsenic concentrations in plants increased in the approximate order: Retama sphaerocarpa < Pteridium aquilinum < Erica australis < Juncus effusus < Phalaris caerulescens < Spergula arvensis in site 1. The soil-plant transfer coefficients for As ranged from 0.001 to 0.21 in site 1 and from 0.004 to 0.016 in site 2. The bioconcentration factor based on water-soluble As of soil varied from 3.2 to 593.9 in the plants of site 1 whereas it varied from 2.1 to 20.7 in the plants of site 2. To our knowledge, this is the first study in Europe to report that the fern species P. aquilinum accumulates extremely low contents of As in its fronds despite high As levels in the soils. Therefore, the S. arvensis, P. caerulescens and J. effusus plant species grown in this area might be used to partly remove the bioavailable toxic As for the purpose of minimization of mining impacts until hypothetical hyperaccumulating and/or transgenic plants could be transplanted for the phytoremediation of As contaminated soils.

Chloromethane formation and degradation in the fern phyllosphere.

PubMed

Jaeger, Nicole; Besaury, Ludovic; Röhling, Amelie Ninja; Koch, Fabien; Delort, Anne-Marie; Gasc, Cyrielle; Greule, Markus; Kolb, Steffen; Nadalig, Thierry; Peyret, Pierre; Vuilleumier, Stéphane; Amato, Pierre; Bringel, Françoise; Keppler, Frank

2018-09-01

Chloromethane (CH 3 Cl) is the most abundant halogenated trace gas in the atmosphere. It plays an important role in natural stratospheric ozone destruction. Current estimates of the global CH 3 Cl budget are approximate. The strength of the CH 3 Cl global sink by microbial degradation in soils and plants is under discussion. Some plants, particularly ferns, have been identified as substantial emitters of CH 3 Cl. Their ability to degrade CH 3 Cl remains uncertain. In this study, we investigated the potential of leaves from 3 abundant ferns (Osmunda regalis, Cyathea cooperi, Dryopteris filix-mas) to produce and degrade CH 3 Cl by measuring their production and consumption rates and their stable carbon and hydrogen isotope signatures. Investigated ferns are able to degrade CH 3 Cl at rates from 2.1 to 17 and 0.3 to 0.9μgg dw -1 day - 1 for C. cooperi and D. filix-mas respectively, depending on CH 3 Cl supplementation and temperature. The stable carbon isotope enrichment factor of remaining CH 3 Cl was -39±13‰, whereas negligible isotope fractionation was observed for hydrogen (-8±19‰). In contrast, O. regalis did not consume CH 3 Cl, but produced it at rates ranging from 0.6 to 128μgg dw -1 day - 1 , with stable isotope values of -97±8‰ for carbon and -202±10‰ for hydrogen, respectively. Even though the 3 ferns showed clearly different formation and consumption patterns, their leaf-associated bacterial diversity was not notably different. Moreover, we did not detect genes associated with the only known chloromethane utilization pathway "cmu" in the microbial phyllosphere of the investigated ferns. Our study suggests that still unknown CH 3 Cl biodegradation processes on plants play an important role in global cycling of atmospheric CH 3 Cl. Copyright © 2018 Elsevier B.V. All rights reserved.

Origin of the Hawaiian rainforest ecosystem and its evolution in long-term primary succession

NASA Astrophysics Data System (ADS)

Mueller-Dombois, D.; Boehmer, H. J.

2013-02-01

Born among volcanoes in the north central Pacific about 4 million years ago, the Hawaiian rainforest became assembled from spores of algae, fungi, lichens, bryophytes, ferns and from seeds of about 275 flowering plants that over the millenia evolved into ca. 1000 endemic species. Outstanding among the forest builders were the tree ferns (Cibotium spp.) and the 'Ōhi'a lehua trees (Metrosideros spp.), which still dominate the Hawaiian rainforest ecosystem today. The structure of this forest is simple. The canopy in closed mature rainforests is dominated by cohorts of Metrosideros polymorpha and the undergrowth by tree fern species of Cibotium. When a new lava flow cuts through this forest, kipuka are formed, i.e. islands of remnant vegetation. On the new volcanic substrate, the assemblage of plant life-forms is similar as during the evolution of this system. In open juvenile forests, a mat-forming fern, the uluhe fern (Dicranopteris lineraris) becomes established. It inhibits further regeneration of the dominant 'Ōhi'a tree, thereby reinforcing the cohort structure of the canopy guild. In the later part of its life cycle, the canopy guild breaks down often in synchrony. The trigger is hypothesized to be a climatic perturbation. After that disturbance the forest becomes reestablished in about 30-40 yr. As the volcanic surfaces age, they go from a mesotrophic to a eutrophic phase, reaching a biophilic nutrient climax by about 1-25 K yr. Thereafter, a regressive oligotrophic phase follows; the soils become exhausted of nutrients. The shield volcanoes break down. Marginally, forest habitats change into bogs and stream ecosystems. The broader 'Ōhi'a rainforest redeveloping in the more dissected landscapes of the older islands looses stature, often forming large gaps that are invaded by the aluminum tolerant uluhe fern. The 'Ōhi'a trees still thrive on soils rejuvenated from landslides and from Asian dust on the oldest (5 million year old) island Kaua'i but their stature and living biomass is greatly diminished.

Two fern species new to New Hampshire, with comments on the generation of calcareous-like habitat by base-poor rocks

Treesearch

Scott W. Bailey

2013-01-01

Incidental to other field investigations, I happened upon small populations of two fern species not previously reported from New Hampshire: Pellaea atropurpurea (L.) Link and Dryopteris filix-mas (L.) Schott. Both species are typically associated with calcareous habitats, although limestone and marble are nearly absent from New...

Development of reproduction in Allegheny hardwood stands after herbicide-clearcuts and herbicide-shelterwood cuts

Treesearch

Stephen B. Horsley

1982-01-01

Dense ground covers of fern and grass interfere with the regeneration of Allegheny hardwoods. An herbicide containing N-phosphonomethyl glycine controls the fern and grass, but also kills advance reproduction of desirable tree species. Preliminary results of an experiment comparing regeneration 3 years after herbicide-clearcuts and herbicide-shelterwood seed cuts...

Conservation assessment for southern maidenhair fern and stream orchid in the Black Hills National Forest South Dakota and Wyoming

Treesearch

J. Hope Hornbeck; Deanna J. Reyher; Carolyn Hull Sieg; Reed W. Crook

2003-01-01

Southern maidenhair fern (Adiantum capillus-veneris L.; Pteridaceae) is a cosmopolitan species that is widely distributed in southern North America. Stream orchid (Epipactis gigantea Dougl. ex Hook.; Orchidaceae) occurs in western North America from British Columbia, Canada; south to California, Arizona and New Mexico; and east to...

The nucleotide sequences of 5S rRNAs from a fern Dryopteris acuminata and a horsetail Equisetum arvense.

PubMed Central

Hori, H; Osawa, S; Takaiwa, F; Sugiura, M

1984-01-01

The nucleotide sequences from two Pteridophyta species, a fern Dryopteris acuminata and a horsetail Equisetum arvense have been determined. These two sequences are more related to those of the Bryophyta species (88% identity on average) than to those of seed plants (84% identity on average). PMID:6538332

Western sword fern avoids the extreme drought of 2012-2014

Treesearch

Emily E. Burns; Peter Cowan; Wendy Baxter; Deborah Zierten; Jarmilla Pittermann

2017-01-01

The California drought of 2012 to 2014 was the most severe drought on record for the last century and likely millennium. Warm temperatures with below-average precipitation compounded over the three-year period, creating significant and sustained aridity over the course of three growing seasons throughout the coast redwood ecosystem. The citizen science project, Fern...

Prospects for biological control of Old World climbing fern, Lygodium microphyllum - Encouraging results with the brown lygodium moth and update on other agents

USDA-ARS?s Scientific Manuscript database

Old World climbing fern, Lygodium microphyllum is one of the most problematic invasive weeds affecting natural areas in southern and central Florida. Management of this weed using fire or mechanical methods is ineffective, because the weed rapidly regrows from rhizomes, while herbicidal management i...

2016 Award for Distinguished Contributions to the International Advancement of Psychology: Héctor Fernández-Álvarez.

PubMed

2016-11-01

The Award for Distinguished Contributions to the International Advancement of Psychology is given to individuals who have made sustained and enduring contributions to international cooperation and the advancement of knowledge in psychology. The 2016 award winner is Héctor Fernández-Álvarez, who "has woven a sophisticated network of international cooperation in psychotherapy research, training, and service provision throughout Latin America, Europe, and the United States." He was selected for his outstanding, innovative contributions to psychotherapy integration, clinical supervision, and the personal style of the therapist. Dr. Fernández-Álvarez's award citation, biography, and a selected bibliography are presented here. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

A site for sori: Ecophysiology of fertile-sterile leaf dimorphy in ferns.

PubMed

Watkins, James E; Churchill, Amber C; Holbrook, N Michele

2016-05-01

Reproduction often requires significant investment and can move resources away from growth and maintenance; maintaining a balance between reproduction and growth can involve trade-offs. Extreme functional specialization has separated reproduction and photosynthesis in most seed plants, yet ferns use the laminar surface of their fronds for both reproduction and photosynthesis. This dual function selects for a variety of frond morphologies that range from no specialization (monomorphy) to extreme dimorphy between fertile and sterile fronds (holodimorphy). Here we examined the ecological and physiological consequences of variation in frond dimorphy in ferns, evaluated reproductive trade-offs across a dimorphy gradient, and speculate on factors controlling the occurrence of holodimorphy. Ecophysiological measurements of photosynthetic rate, water potential, hydraulic conductivity, and gross morphological comparisons of frond area and angle were used to evaluate differences between fertile and sterile fronds. We examined three temperate and three tropical fern species that vary in degree of fertile-sterile dimorphy. Holodimorphic species produced fewer fertile fronds, which had significantly higher respiratory rates than in sterile fronds on the same plant or in any frond produced on monomorphic species; hemidimorphic species were frequently intermediate. We found no differences in vulnerability to cavitation between fertile and sterile fronds. In dimorphic species, fertile fronds had higher (less negative) water potential and lower stipe hydraulic conductivity relative than in sterile fronds. Fertile-sterile dimorphy in ferns appears to come at considerable carbon cost in holodimorohic species. It is possible that the relative costs of this reproductive system are offset by increased spore dispersal, yet such trade-offs require further exploration. © 2016 Botanical Society of America.

Seasonal changes in tissue-water relations for eight species of ferns during historic drought in California.

PubMed

Holmlund, Helen I; Lekson, Victoria M; Gillespie, Breahna M; Nakamatsu, Nicole A; Burns, Amanda M; Sauer, Kaitlyn E; Pittermann, Jarmila; Davis, Stephen D

2016-09-01

California experienced severe drought between 2012 and 2016. During this period, we compared seasonal changes in tissue-water relations among eight fern species in the Santa Monica Mountains of southern California to elucidate differential mechanisms of drought survival and physiological performance during extreme water deficits. We monitored seasonal changes in water potential (Ψmd) and dark-adapted chlorophyll fluorescence (Fv/Fm), assessed tissue-water relations including osmotic potential at saturation and the turgor loss point (Ψπ, sat and Ψπ, tlp), and measured, for two evergreen species, xylem-specific and leaf-specific hydraulic conductivity (Ks and Kl) and vulnerability of stem xylem to water stress-induced embolism (water potential at 50% loss hydraulic conductivity, Ψ50). Species grew in either riparian or chaparral understory. The five chaparral species had a wider range of seasonal water potentials, root depths, and frond phenological traits, including one evergreen, two summer-deciduous, and two desiccation-tolerant (resurrection) species. Evergreen species were especially diverse, with an evergreen riparian species maintaining seasonal water potentials above -1.3 MPa, while an evergreen chaparral species had seasonal water potentials below -8 MPa. In those two species the Ψ50 values were -2.5 MPa and -4.3 MPa, respectively. Observed differences in physiological performance among eight fern species reflected niche partitioning in water utilization and habitat preference associated with distinct phenological traits. We predict differential survival among fern species as future drought events in California intensify, with desiccation-tolerant resurrection ferns being the most resistant. © 2016 Botanical Society of America.

Community assembly of the ferns of Florida.

PubMed

Sessa, Emily B; Chambers, Sally M; Li, Daijiang; Trotta, Lauren; Endara, Lorena; Burleigh, J Gordon; Baiser, Benjamin

2018-03-01

Many ecological and evolutionary processes shape the assembly of organisms into local communities from a regional pool of species. We analyzed phylogenetic and functional diversity to understand community assembly of the ferns of Florida at two spatial scales. We built a phylogeny for 125 of the 141 species of ferns in Florida using five chloroplast markers. We calculated mean pairwise dissimilarity (MPD) and mean nearest taxon distance (MNTD) from phylogenetic distances and functional trait data for both spatial scales and compared the results to null models to assess significance. Our results for over vs. underdispersion in functional and phylogenetic diversity differed depending on spatial scale and metric considered. At the county scale, MPD revealed evidence for phylogenetic overdispersion, while MNTD revealed phylogenetic and functional underdispersion, and at the conservation area scale, MPD revealed phylogenetic and functional underdispersion while MNTD revealed evidence only of functional underdispersion. Our results are consistent with environmental filtering playing a larger role at the smaller, conservation area scale. The smaller spatial units are likely composed of fewer local habitat types that are selecting for closely related species, with the larger-scale units more likely to be composed of multiple habitat types that bring together a larger pool of species from across the phylogeny. Several aspects of fern biology, including their unique physiology and water relations and the importance of the independent gametophyte stage of the life cycle, make ferns highly sensitive to local, microhabitat conditions. © 2018 The Authors. American Journal of Botany is published by Wiley Periodicals, Inc. on behalf of the Botanical Society of America.

Cytological and Proteomic Analyses of Osmunda cinnamomea Germinating Spores Reveal Characteristics of Fern Spore Germination and Rhizoid Tip Growth.

PubMed

Suo, Jinwei; Zhao, Qi; Zhang, Zhengxiu; Chen, Sixue; Cao, Jian'guo; Liu, Guanjun; Wei, Xing; Wang, Tai; Yang, Chuanping; Dai, Shaojun

2015-09-01

Fern spore is a good single-cell model for studying the sophisticated molecular networks in asymmetric cell division, differentiation, and polar growth. Osmunda cinnamomea L. var. asiatica is one of the oldest fern species with typical separate-growing trophophyll and sporophyll. The chlorophyllous spores generated from sporophyll can germinate without dormancy. In this study, the spore ultrastructure, antioxidant enzyme activities, as well as protein and gene expression patterns were analyzed in the course of spore germination at five typical stages (i.e. mature spores, rehydrated spores, double-celled spores, germinated spores, and spores with protonemal cells). Proteomic analysis revealed 113 differentially expressed proteins, which were mainly involved in photosynthesis, reserve mobilization, energy supplying, protein synthesis and turnover, reactive oxygen species scavenging, signaling, and cell structure modulation. The presence of multiple proteoforms of 25 differentially expressed proteins implies that post-translational modification may play important roles in spore germination. The dynamic patterns of proteins and their encoding genes exhibited specific characteristics in the processes of cell division and rhizoid tip growth, which include heterotrophic and autotrophic metabolisms, de novo protein synthesis and active protein turnover, reactive oxygen species and hormone (brassinosteroid and ethylene) signaling, and vesicle trafficking and cytoskeleton dynamic. In addition, the function skew of proteins in fern spores highlights the unique and common mechanisms when compared with evolutionarily divergent spermatophyte pollen. These findings provide an improved understanding of the typical single-celled asymmetric division and polar growth during fern spore germination. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

Somatic embryogenesis in ferns: a new experimental system.

PubMed

Mikuła, Anna; Pożoga, Mariusz; Tomiczak, Karolina; Rybczyński, Jan J

2015-05-01

Somatic embryogenesis has never been reported in ferns. The study showed that it is much easier to evoke the acquisition and expression of embryogenic competence in ferns than in spermatophytes. We discovered that the tree fern Cyathea delgadii offers an effective model for the reproducible and rapid formation of somatic embryos on hormone-free medium. Our study provides cyto-morphological evidence for the single cell origin and development of somatic embryos. Somatic embryogenesis (SE) in both primary and secondary explants was induced on half-strength micro- and macro-nutrients Murashige and Skoog medium without the application of exogenous plant growth regulators, in darkness. The early stage of SE was characterized by sequential perpendicular cell divisions of an individual epidermal cell of etiolated stipe explant. These resulted in the formation of a linear pro-embryo. Later their development resembled that of the zygotic embryo. We defined three morphogenetic stages of fern somatic embryo development: linear, early and late embryonic leaf stage. The transition from somatic embryo to juvenile sporophyte was quick and proceeded without interruption caused by dormancy. Following 9 weeks of culture the efficiency of somatic embryogenesis reached 12-13 embryos per responding explant. Spontaneous formation of somatic embryos and callus production, which improved the effectiveness of the process sevenfold in 10-month-long culture, occurred without subculturing. The tendency for C. delgadii to propagate by SE in vitro makes this species an excellent model for studies relating to asexual embryogenesis and the endogenous hormonal regulation of that process and opens new avenues of experimentation.

Conference Proceedings: 14th Annual Review of Progress in Applied Computational Electromagnetics at the Naval Postgraduate School, Monterey, CA, March 16-20, 1998. Volume 1

DTIC Science & Technology

1998-03-01

computer codes are now available for detailed dosimetric calculations for human exposure to low-frequency magnetic fields [Dawson and Stuehly. 1997...3] William H. Bailey, Steave H. Su, T. Dan Bracken, and Robert Kavet. Summary and evaluation of guidelines for occupational exposure to power...APPLICATIONS Chairs: Cynthia Furse and Maria A. Stuchly "EM Interaction Evaluation of Handset Antennas and Human Head: A Hybrid Technique", K.W. Kim and Y

Wildlife of southern forests habitat & management (Chapter 2): Early History

Treesearch

James G. Dickson

2003-01-01

According to fossil records from coal beds, primeval forests of the South eons ago were complex forests of club moss trees and ferns (Burdette 1995). Since that time forest composition and distribution have changed in response to natural phenomena and later, to the influences of man. Over a long period of time primeval forests evolved from club mosses and ferns...

Sensing Red, White & Blue: Using Spores of the Sensitive Fern to Introduce Important Concepts in Biology

ERIC Educational Resources Information Center

Kiss, Helen G.; Kiss, John Z.

2005-01-01

Contrary to popular belief, plants are very much in tune and in time with their immediate environment. The most important environmental cues for plants are light and gravity. In this article, the authors discuss the effects of light on plant development and use the spores of the sensitive fern (Onoclea sensibilis) in laboratory exercises to…

Grass or fern competition reduce growth and survival of planted tree seedlings

Treesearch

Larry H. McCormick; Todd W. Bowersox

1997-01-01

Bareroot seedlings of northern red oak, white ash, yellow-poplar and white pine were planted into herbaceous communities at three forested sites in central Pennsylvania that were clearcut 0 to 1 year earlier. Seedlings were grown 4 years in the presence and absence of either an established grass or hay-scented fern community. Survival and height growth were measured...

Rates of molecular evolution in tree ferns are associated with body size, environmental temperature, and biological productivity.

PubMed

Barrera-Redondo, Josué; Ramírez-Barahona, Santiago; Eguiarte, Luis E

2018-05-01

Variation in rates of molecular evolution (heterotachy) is a common phenomenon among plants. Although multiple theoretical models have been proposed, fundamental questions remain regarding the combined effects of ecological and morphological traits on rate heterogeneity. Here, we used tree ferns to explore the correlation between rates of molecular evolution in chloroplast DNA sequences and several morphological and environmental factors within a Bayesian framework. We revealed direct and indirect effects of body size, biological productivity, and temperature on substitution rates, where smaller tree ferns living in warmer and less productive environments tend to have faster rates of molecular evolution. In addition, we found that variation in the ratio of nonsynonymous to synonymous substitution rates (dN/dS) in the chloroplast rbcL gene was significantly correlated with ecological and morphological variables. Heterotachy in tree ferns may be influenced by effective population size associated with variation in body size and productivity. Macroevolutionary hypotheses should go beyond explaining heterotachy in terms of mutation rates and instead, should integrate population-level factors to better understand the processes affecting the tempo of evolution at the molecular level. © 2018 The Author(s). Evolution © 2018 The Society for the Study of Evolution.

Ferns: the missing link in shoot evolution and development.

PubMed

Plackett, Andrew R G; Di Stilio, Verónica S; Langdale, Jane A

2015-01-01

Shoot development in land plants is a remarkably complex process that gives rise to an extreme diversity of forms. Our current understanding of shoot developmental mechanisms comes almost entirely from studies of angiosperms (flowering plants), the most recently diverged plant lineage. Shoot development in angiosperms is based around a layered multicellular apical meristem that produces lateral organs and/or secondary meristems from populations of founder cells at its periphery. In contrast, non-seed plant shoots develop from either single apical initials or from a small population of morphologically distinct apical cells. Although developmental and molecular information is becoming available for non-flowering plants, such as the model moss Physcomitrella patens, making valid comparisons between highly divergent lineages is extremely challenging. As sister group to the seed plants, the monilophytes (ferns and relatives) represent an excellent phylogenetic midpoint of comparison for unlocking the evolution of shoot developmental mechanisms, and recent technical advances have finally made transgenic analysis possible in the emerging model fern Ceratopteris richardii. This review compares and contrasts our current understanding of shoot development in different land plant lineages with the aim of highlighting the potential role that the fern C. richardii could play in shedding light on the evolution of underlying genetic regulatory mechanisms.

Mitigating arsenic contamination in rice plants with an aquatic fern, Marsilea minuta.

PubMed

Hassi, Ummehani; Hossain, Md Tawhid; Huq, S M Imamul

2017-10-10

Dangers of arsenic contamination are well known in human civilization. The threat increases when arsenic is accumulated in food and livestock through irrigated crops or animal food. Hence, it is important to mitigate the effects of arsenic as much as possible. This paper discusses a process for reducing the level of arsenic in different parts of rice plants with an aquatic fern, Marsilea minuta L. A pot experiment was done to study the possibility of using Marsilea minuta as a phytoremediator of arsenic. Rice and Marsilea minuta were allowed to grow together in soils. As a control, Marsilea minuta was also cultured alone in the presence and absence of arsenic (applied at 1 mg/L as irrigation water). We did not find any significant change in the growth of rice due to the association of Marsilea minuta, though it showed a reduction of approximately 58.64% arsenic accumulation in the roots of rice grown with the association of fern compared to that grown without fern. We measured a bioaccumulation factor (BF) of > 5.34, indicating that Marsilea minuta could be a good phytoremediator of arsenic in rice fields.

Potential of the aquatic fern Azolla filiculoides in biodegradation of an azo dye: modeling of experimental results by artificial neural networks.

PubMed

Khataee, A R; Movafeghi, A; Vafaei, F; Lisar, S Y Salehi; Zarei, M

2013-01-01

The potential of an aquatic fern, Azolla filiculoides, in phytoremediation of a mono azo dye solution, C.I. Acid Blue 92 (AB92), was studied. The effects of operational parameters such as reaction time, initial dye concentration, fern fresh weight, pH, temperature and reusability of the fern on biodegradation efficiency were investigated. The intermediate compounds produced by biodegradation process were analyzed using GC-MS analysis. An artificial neural network (ANN) model was developed to predict the biodegradation efficiency. The findings indicated that ANN provides reasonable predictive performance (R2 = 0.961). The effects of AB92 solutions (10 and 20 mg L(-1)) on growth, chlorophylls and carotenoids content, activity of antioxidant enzymes such as superoxide dismutase, peroxidase and catalase and formation of malondialdehyde were analyzed. AB92 generally showed inhibitory effects on the growth. Moreover, photosynthetic pigments in the fronds significantly decreased in the treatments. An increase was detected for lipid peroxidation and antioxidant enzymes activity, suggesting that AB92 caused reactive oxygen species production in Azolla fronds, which were scavenged by induced activities of antioxidant enzymes.

Contrasting Patterns of Genetic Variation in Central and Peripheral Populations of Dryopteris fragrans (Fragrant Wood Fern) and Implications for Colonization Dynamics and Conservation

Treesearch

J.R. Bouchard; D.D. Fernando; S.W. Bailey; J. Weber-Townsend; D.J. Leopold

2017-01-01

Premise of research. Ferns are vital components of temperate and tropical ecosystems, but they have not been examined in the context of a central-peripheral hypothesis. Dryopteris fragrans is an ideal species to examine the genetic variation between central and peripheral populations because of its arctic north to temperate...

Origin of the Hawaiian rainforest and its transition states in long-term primary succession

NASA Astrophysics Data System (ADS)

Mueller-Dombois, D.; Boehmer, H. J.

2013-07-01

This paper addresses the question of transition states in the Hawaiian rainforest ecosystem with emphasis on their initial developments. Born among volcanoes in the north central Pacific about 4 million years ago, the Hawaiian rainforest became assembled from spores of algae, fungi, lichens, bryophytes, ferns and from seeds of about 275 flowering plants that over the millennia evolved into ca. 1000 endemic species. Outstanding among the forest builders were the tree ferns (Cibotium spp.) and the 'ōhi'a lehua trees (Metrosideros spp.), which still dominate the Hawaiian rainforest ecosystem today. The structure of this forest is simple. The canopy in closed mature rainforests is dominated by cohorts of Metrosideros polymorpha and the undergrowth by tree fern species of Cibotium. When a new lava flow cuts through this forest, kipuka are formed, i.e., islands of remnant vegetation. On the new volcanic substrate, the assemblage of plant life forms is similar to the assemblage during the evolution of this system. In open juvenile forests, a mat-forming fern, the uluhe fern (Dicranopteris linearis), becomes established. It inhibits further regeneration of the dominant 'ōhi'a tree, thereby reinforcing the cohort structure of the canopy guild. In the later part of its life cycle, the canopy guild breaks down often in synchrony. The trigger is hypothesized to be a climatic perturbation. After the disturbance, the forest becomes reestablished in about 30-40 yr. As the volcanic surfaces age, they go from a mesotrophic to a eutrophic phase, reaching a biophilic nutrient climax by about 1-25 K yr. Thereafter, a regressive oligotrophic phase follows; the soils become exhausted of nutrients. The shield volcanoes break down. Marginally, forest habitats change into bogs and stream ecosystems. The broader 'ōhi'a rainforest redeveloping in the more dissected landscapes of the older islands loses stature, often forming large gaps that are invaded by the aluminum tolerant uluhe fern. The 'ōhi'a trees still thrive on soils rejuvenated from landslides and from Asian dust on the oldest (5 million years old) island Kaua'i but their stature and living biomass is greatly diminished.

Palynologic and petrographic intervals in the upper Pennsylvanian McLeansboro Group, Western Kentucky

USGS Publications Warehouse

Hower, J.C.; Helfrich, C.T.; Williams, D.A.

1994-01-01

The McLeansboro Group (formerly the Sturgis Formation) in the Western Kentucky coal field spans the upper Desmoinesian (Westphalian D) and the Missourian and Virgilian series (Stephanian). Extensive drilling has demonstrated the lateral continuity of major and minor beds in the group, making it possible to study vertical and lateral changes in palynology and petrology. Significant features of the McLeansboro Group are the marine zones over most of the coals and paleochannels, which are the only disruptions to the continuity of other lithologies. The Desmoinesian Baker (No. 13) and Wheatcroft (No. 13a) coal beds were included in the study but the primary emphasis is on the Missourian and Virgilian coals. Patoka Formation (lower Missourian) coals are dominated by tree fern spores with lesser amounts of sphenopsids, ferns and cordaites spores. This is in marked contrast to the arborescent lycopod-dominated Desmoinesian coals. Only the No. 15 coal bed exceeds 80% vitrinite: the vitrinite content of the No. 16 coal bed is less than 72%, the lowest of any Western Kentucky humic coal. The Bond Formation (upper Missourian) represents a distinct floristic interval, with a greater diversity of plant groups than in the Patoka Formation. Herbaceous lycopod spores, which are relatively minor contributors to the Patoka coals, are common in the Bond Formation. The coals generally exceed 80% vitrinite. The Mattoon Formation (Virgillian) coals have a variety of palynomorph assemblages. The low-sulfur Geiger Lake coal bed is dominated by tree fern spores, with important contributions from other ferns and sphenopsids. Similar to the underlying tree fern interval, vitrinite contents are less than 80%. The uppermost Mattoon coals are dominated by tree ferns and are notable in being the only coals more than 1 m thick in the Stephanian portion of the section, with the top coal being 4.3 m thick. The uppermost coals generally contain more than 80% vitrinite. The Permian Mauzy Formation overlies the McLeansboro Group. The palynologic/petrographic intervals appear to represent fluctuating dry (low vitrinite) and wet intervals within the Stephanian, which was itself drier than the Westphalian D. ?? 1994.

UPLC-MS/MS determination of ptaquiloside and pterosin B in preserved natural water.

PubMed

Clauson-Kaas, Frederik; Hansen, Hans Christian Bruun; Strobel, Bjarne W

2016-11-01

The naturally occurring carcinogen ptaquiloside and its degradation product pterosin B are found in water leaching from bracken stands. The objective of this work is to present a new sample preservation method and a fast UPLC-MS/MS method for quantification of ptaquiloside and pterosin B in environmental water samples, employing a novel internal standard. A faster, reliable, and efficient method was developed for isolation of high purity ptaquiloside and pterosin B from plant material for use as analytical standards, with purity verified by 1 H-NMR. The chemical analysis was performed by cleanup and preconcentration of samples with solid phase extraction, before analyte quantification with UPLC-MS/MS. By including gradient elution and optimizing the liquid chromatography mobile phase buffer system, a total run cycle of 5 min was achieved, with method detection limits, including preconcentration, of 8 and 4 ng/L for ptaquiloside and pterosin B, respectively. The use of loganin as internal standard improved repeatability of the determination of both analytes, though it could not be employed for sample preparation. Buffering raw water samples in situ with ammonium acetate to pH ∼5.5 decisively increased sample integrity at realistic transportation and storing conditions prior to extraction. Groundwater samples collected in November 2015 at the shallow water table below a Danish bracken stand were preserved and analyzed using the above methods, and PTA concentrations of 3.8 ± 0.24 μg/L (±sd, n = 3) were found, much higher than previously reported. Graphical abstract Workflow overview of ptaquiloside determination.

Ongoing changes in migration phenology and winter residency at Bracken Bat Cave.

PubMed

Stepanian, Phillip M; Wainwright, Charlotte E

2018-02-14

Bats play an important role in agroecology and are effective bioindicators of environmental conditions, but little is known about their fundamental migration ecology, much less how these systems are responding to global change. Some of the world's largest bat populations occur during the summer in the south-central United States, when millions of pregnant females migrate from lower latitudes to give birth in communal maternity colonies. Despite a relatively large volume of research into these colonies, many fundamental questions regarding their abundance-including their intra- and interseasonal variability-remain unanswered, and even estimating the size of individual populations has been a long-running challenge. Overall, monitoring these bat populations at high temporal resolution (e.g., nightly) and across long time spans (e.g., decades) has been impossible. Here, we show 22 continuous years of nightly population counts at Bracken Cave, a large bat colony in south-central Texas, enabling the first climate-scale phenological analysis. Using quantitative radar monitoring, we found that spring migration and the summer reproductive cycle have advanced by approximately 2 weeks over the study period. Furthermore, we quantify the ongoing growth of a newly-established overwintering population that indicates a system-wide response to changing environmental conditions. Our observations reveal behavioral plasticity in bats' ability to adapt to changing resource availability, and provide the first long-term quantification of their response to a changing climate. As aerial insectivores, these changes in bat phenology and propensity for overwintering indicate probable shifts in prey availability, with clear implications for pest management across wider regional agrisystems. © 2018 John Wiley & Sons Ltd.

The Neural Basis of Decision-Making and Reward Processing in Adults with Euthymic Bipolar Disorder or Attention-Deficit/Hyperactivity Disorder (ADHD)

PubMed Central

Ibanez, Agustin; Cetkovich, Marcelo; Petroni, Agustin; Urquina, Hugo; Baez, Sandra; Gonzalez-Gadea, Maria Luz; Kamienkowski, Juan Esteban; Torralva, Teresa; Torrente, Fernando; Strejilevich, Sergio; Teitelbaum, Julia; Hurtado, Esteban; Guex, Raphael; Melloni, Margherita; Lischinsky, Alicia; Sigman, Mariano; Manes, Facundo

2012-01-01

Background Attention-deficit/hyperactivity disorder (ADHD) and bipolar disorder (BD) share DSM-IV criteria in adults and cause problems in decision-making. Nevertheless, no previous report has assessed a decision-making task that includes the examination of the neural correlates of reward and gambling in adults with ADHD and those with BD. Methodology/Principal Findings We used the Iowa gambling task (IGT), a task of rational decision-making under risk (RDMUR) and a rapid-decision gambling task (RDGT) which elicits behavioral measures as well as event-related potentials (ERPs: fERN and P3) in connection to the motivational impact of events. We did not observe between-group differences for decision-making under risk or ambiguity (RDMUR and IGT); however, there were significant differences for the ERP-assessed RDGT. Compared to controls, the ADHD group showed a pattern of impaired learning by feedback (fERN) and insensitivity to reward magnitude (P3). This ERP pattern (fERN and P3) was associated with impulsivity, hyperactivity, executive function and working memory. Compared to controls, the BD group showed fERN- and P3-enhanced responses to reward magnitude regardless of valence. This ERP pattern (fERN and P3) was associated with mood and inhibitory control. Consistent with the ERP findings, an analysis of source location revealed reduced responses of the cingulate cortex to the valence and magnitude of rewards in patients with ADHD and BD. Conclusions/Significance Our data suggest that neurophysiological (ERPs) paradigms such as the RDGT are well suited to assess subclinical decision-making processes in patients with ADHD and BD as well as for linking the cingulate cortex with action monitoring systems. PMID:22624011

Air humidity as key determinant of morphogenesis and productivity of the rare temperate woodland fern Polystichum braunii.

PubMed

Schwerbrock, R; Leuschner, C

2016-07-01

(1) Most ferns are restricted to moist and shady habitats, but it is not known whether soil moisture or atmospheric water status are decisive limiting factors, or if both are equally important. (2) Using the rare temperate woodland fern Polystichum braunii, we conducted a three-factorial climate chamber experiment (soil moisture (SM) × air humidity (RH) × air temperature (T)) to test the hypotheses that: (i) atmospheric water status (RH) exerts a similarly large influence on the fern's biology as soil moisture, and (ii) both a reduction in RH and an increase in air temperature reduce vigour and growth. (3) Nine of 11 morphological, physiological and growth-related traits were significantly influenced by an increase in RH from 65% to 95%, leading to higher leaf conductance, increased above- and belowground productivity, higher fertility, more epidermal trichomes and fewer leaf deformities under high air humidity. In contrast, soil moisture variation (from 66% to 70% in the moist to ca. 42% in the dry treatment) influenced only one trait (specific leaf area), and temperature variation (15 °C versus 19 °C during daytime) only three traits (leaf conductance, root/shoot ratio, specific leaf area); RH was the only factor affecting productivity. (4) This study is the first experimental proof for a soil moisture-independent air humidity effect on the growth of terrestrial woodland ferns. P. braunii appears to be an air humidity hygrophyte that, whithin the range of realistic environmental conditions set in this study, suffers more from a reduction in RH than in soil moisture. A climate warming-related increase in summer temperatures, however, seems not to directly threaten this endangered species. © 2016 German Botanical Society and The Royal Botanical Society of the Netherlands.

The neural basis of decision-making and reward processing in adults with euthymic bipolar disorder or attention-deficit/hyperactivity disorder (ADHD).

PubMed

Ibanez, Agustin; Cetkovich, Marcelo; Petroni, Agustin; Urquina, Hugo; Baez, Sandra; Gonzalez-Gadea, Maria Luz; Kamienkowski, Juan Esteban; Torralva, Teresa; Torrente, Fernando; Strejilevich, Sergio; Teitelbaum, Julia; Hurtado, Esteban; Guex, Raphael; Melloni, Margherita; Lischinsky, Alicia; Sigman, Mariano; Manes, Facundo

2012-01-01

Attention-deficit/hyperactivity disorder (ADHD) and bipolar disorder (BD) share DSM-IV criteria in adults and cause problems in decision-making. Nevertheless, no previous report has assessed a decision-making task that includes the examination of the neural correlates of reward and gambling in adults with ADHD and those with BD. We used the Iowa gambling task (IGT), a task of rational decision-making under risk (RDMUR) and a rapid-decision gambling task (RDGT) which elicits behavioral measures as well as event-related potentials (ERPs: fERN and P3) in connection to the motivational impact of events. We did not observe between-group differences for decision-making under risk or ambiguity (RDMUR and IGT); however, there were significant differences for the ERP-assessed RDGT. Compared to controls, the ADHD group showed a pattern of impaired learning by feedback (fERN) and insensitivity to reward magnitude (P3). This ERP pattern (fERN and P3) was associated with impulsivity, hyperactivity, executive function and working memory. Compared to controls, the BD group showed fERN- and P3-enhanced responses to reward magnitude regardless of valence. This ERP pattern (fERN and P3) was associated with mood and inhibitory control. Consistent with the ERP findings, an analysis of source location revealed reduced responses of the cingulate cortex to the valence and magnitude of rewards in patients with ADHD and BD. Our data suggest that neurophysiological (ERPs) paradigms such as the RDGT are well suited to assess subclinical decision-making processes in patients with ADHD and BD as well as for linking the cingulate cortex with action monitoring systems.

Biochemical and growth performance of the aquatic macrophyte Azolla filiculoides to sub-chronic exposure to cylindrospermopsin.

PubMed

Santos, Catarina; Azevedo, Joana; Campos, Alexandre; Vasconcelos, Vitor; Pereira, Ana L

2015-11-01

Physiological and biochemical effects of cylindrospermopsin (CYN), a cyanobacterial toxin that inhibits protein synthesis and released during a harmful cyanobacterial bloom, has been overlooked in plants. Therefore, at the present research, the toxic effects (physiological and biochemical) of a crude extract containing CYN were assessed in the aquatic fern Azolla filiculoides exposed to three concentrations (0.05, 0.5 and 5 μg CYN mL(-1)). At 5 μg CYN mL(-1), fern growth rate has showed a drastic decrease (0.001 g g(-1) day(-1)) corresponding to a 99.8% inhibition, but at the concentrations of 0.05 and 0.5 μg CYN mL(-1) the growth rate was similar to the control plants. Growth rate also indicated a IC50 of 2.9 μg CYN mL(-1). Those data point to the presence of other compounds in the crude extract may stimulate the fern growth and/or the fern is tolerant to CYN. Chlorophyll (a and b), carotenoids and protein content as well as the activities of glutathione reductase (GR) and glutathione-S-transferase (GST) has increased at 5 μg CYN mL(-1) which may indicate that photosynthesis and protein synthesis are not affected by CYN and the probable activation of defense and detoxifying mechanisms to overcome the effects induced by the presence of CYN. Low uptake of cylindrospermopsin (1.314 μg CYN g(-1) FW) and low bioconcentration factor (0.401) point towards to a safe use of A. filiculoides as biofertilizer and as food source, but also indicate that the fern is not suitable for CYN phytoremediation.

Comparative glycan profiling of Ceratopteris richardii 'C-Fern' gametophytes and sporophytes links cell-wall composition to functional specialization.

PubMed

Eeckhout, Sharon; Leroux, Olivier; Willats, William G T; Popper, Zoë A; Viane, Ronald L L

2014-10-01

Innovations in vegetative and reproductive characters were key factors in the evolutionary history of land plants and most of these transformations, including dramatic changes in life cycle structure and strategy, necessarily involved cell-wall modifications. To provide more insight into the role of cell walls in effecting changes in plant structure and function, and in particular their role in the generation of vascularization, an antibody-based approach was implemented to compare the presence and distribution of cell-wall glycan epitopes between (free-living) gametophytes and sporophytes of Ceratopteris richardii 'C-Fern', a widely used model system for ferns. Microarrays of sequential diamino-cyclohexane-tetraacetic acid (CDTA) and NaOH extractions of gametophytes, spores and different organs of 'C-Fern' sporophytes were probed with glycan-directed monoclonal antibodies. The same probes were employed to investigate the tissue- and cell-specific distribution of glycan epitopes. While monoclonal antibodies against pectic homogalacturonan, mannan and xyloglucan widely labelled gametophytic and sporophytic tissues, xylans were only detected in secondary cell walls of the sporophyte. The LM5 pectic galactan epitope was restricted to sporophytic phloem tissue. Rhizoids and root hairs showed similarities in arabinogalactan protein (AGP) and xyloglucan epitope distribution patterns. The differences and similarities in glycan cell-wall composition between 'C-Fern' gametophytes and sporophytes indicate that the molecular design of cell walls reflects functional specialization rather than genetic origin. Glycan epitopes that were not detected in gametophytes were associated with cell walls of specialized tissues in the sporophyte. © The Author 2014. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Applying DNA Barcodes to Identify Closely Related Species of Ferns: A Case Study of the Chinese Adiantum (Pteridaceae)

PubMed Central

Wen, Jun; Ebihara, Atsushi; Li, De-Zhu

2016-01-01

DNA barcoding is a fast-developing technique to identify species by using short and standard DNA sequences. Universal selection of DNA barcodes in ferns remains unresolved. In this study, five plastid regions (rbcL, matK, trnH-psbA, trnL-F and rps4-trnS) and eight nuclear regions (ITS, pgiC, gapC, LEAFY, ITS2, IBR3_2, DET1, and SQD1_1) were screened and evaluated in the fern genus Adiantum from China and neighboring areas. Due to low primer universality (matK) and/or the existence of multiple copies (ITS), the commonly used barcodes matK and ITS were not appropriate for Adiantum. The PCR amplification rate was extremely low in all nuclear genes except for IBR3_2. rbcL had the highest PCR amplification rate (94.33%) and sequencing success rate (90.78%), while trnH-psbA had the highest species identification rate (75%). With the consideration of discriminatory power, cost-efficiency and effort, the two-barcode combination of rbcL+ trnH-psbA seems to be the best choice for barcoding Adiantum, and perhaps basal polypod ferns in general. The nuclear IBR3_2 showed 100% PCR amplification success rate in Adiantum, however, it seemed that only diploid species could acquire clean sequences without cloning. With cloning, IBR3_2 can successfully distinguish cryptic species and hybrid species from their related species. Because hybridization and allopolyploidy are common in ferns, we argue for including a selected group of nuclear loci as barcodes, especially via the next-generation sequencing, as it is much more efficient to obtain single-copy nuclear loci without the cloning procedure. PMID:27603700

Market Basket Analysis: a new tool in ecology to describe chemical relations in the environment--a case study of the fern Athyrium distentifolium in the Tatra National Park in Poland.

PubMed

Samecka-Cymerman, Aleksandra; Stankiewicz, Andrzej; Kolon, Krzysztof; Kempers, Alexander J; Leuven, Rob S E W

2010-09-01

In this study, the novel data mining technique Market Basket Analysis (MBA) was applied for the first time in biogeochemical and ecological investigations. The method was tested on the fern Athyrium distentifolium, in which we measured concentrations of the elements Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, and Zn. Plants were sampled from sites with different types of bedrock in the Tatra National Park in Poland. MBA was used to investigate whether specimens of Athyrium distentifolium that contain elevated levels of certain elements occur more frequently on a specific type of bedrock and to identify relationships between the type of bedrock and the concentrations of the elements in this fern. The results were compared with those of the commonly used principal component and classification analysis (PCCA) technique. MBA and PCCA ordination both yielded distinct groups of ferns growing on different types of bedrock. Although the results of MBA and PCCA were similar, MBA has the advantage of being independent of the size of the data set. In addition, MBA revealed not only dominant elements but, in the case of limestone bedrock, also showed very low concentrations of Cd, Fe, Mn, and Pb in ferns growing on this type of parent material. MBA, thus, appeared to be a promising data mining method to reveal chemical relations in the environment as well as the accumulation of chemical elements in bioindicators. This technique can be used to reveal associations and correlations among items in large data sets collected on a national or even larger scale.

Phenology of 16 species of ferns in a subtropical forest of northeastern Taiwan.

PubMed

Lee, Pei-Hsuan; Lin, Tzer-Tung; Chiou, Wen-Liang

2009-01-01

A knowledge of fern phenology promotes understanding of the biology and ecology of ferns. In this study, the phenology of 16 fern species in a subtropical broadleaf forest (N24 degrees 46', E121 degrees 34') in northeastern Taiwan was monitored from August 1997 to August 2001. Every fern produced both fertile and sterile leaves in each year of the study. Most fertile leaves emerged in February and March, whereas most sterile leaves emerged from May to September. Most leaves reached full expansion during April-July and died during April-August. The average life span of leaves ranged from 4.4 months to 30.3 months. In seven species, fertile leaves lived longer than sterile leaves, but this difference was significant only in Pteris wallichiana. In the other nine species, sterile leaves lived longer than fertile leaves, but the difference was significant only in Cyathea spinulosa, Plagiogyria dunnii, and Plagiogyria adanata. The ephemeral fertile leaves of the two dimorphic species died soon after releasing their spores, at only 5 months of age. However, their sterile leaves survived for over 22 months. The fertile leaves of the other 14 species remained green for almost 2 years after releasing their spores. Sterile leaves remained sterile throughout their lives. Spores matured in May-July and were released in June-August. After spore release, the sporangia detached. No leaf produced a second cohort of sori. Several phenological events, including sterile leaf emergence, leaf expansion and senescence, and spore maturation and release, were significantly positively correlated with temperature but not with precipitation, whereas the emergence of fertile leaves was weakly negatively correlated with temperature and precipitation. However, those correlations varied among different species.

Effect of pH on lead removal from water using tree fern as the sorbent.

PubMed

Ho, Yuh-Shan

2005-07-01

The sorption of lead from water onto an agricultural by-product, tree fern, was examined as a function of pH. The sorption processes were carried out using an agitated and baffled system. Pseudo-second-order kinetic analyses were performed to determine the rate constant of sorption, the equilibrium sorption capacity, and the initial sorption rate. Application of the pseudo-second-order kinetics model produced very high coefficients of determination. Results showed the efficiency of tree fern as a sorbent for lead. The optimum pH for lead removal was between 4 and 7, with pH 4.9 resulting in better lead removal. Ion exchange occurred in the initial reaction period. In addition, a relation between the change in the solution hydrogen ion concentration and equilibrium capacity was developed and is presented.

Vegetative Analysis of the Flookplain of the Trinity River, Texas,

DTIC Science & Technology

1974-09-30

humilis var. longiflora (Gray) Fern. Ruellia Ruellia nudiflora (Gray)1*~ n_ __ Rush Juncus nodatus Coy.f Rush Juncus Torreyi Coy. Rush-foil...scurfpea Psoralea rhombifolia T. & G.J Royal fern Osmunda reai var. §pectabilis (Willd.) Gray Ruellia Ruellia caroliniensis (Walt.) Steud. Ruellia Ruellia ...o’clock Mirabilis nyctaginea (Michx.) 1 Wild indigo Baptisia Nuttalliana, SmallJ Wild onion Allium canadense L. Wild petunia Ruellia Corzoi Tharp & Barkl

Fractal-Based Image Compression

DTIC Science & Technology

1989-09-01

6. A Mercedes Benz symbol generated using an IFS code ................. 21 7. (a) U-A fern and (b) A-0 fern generated with RIFS codes...22 8. Construction of the Mercedes - Benz symbol using RIFS ................ 23 9. The regenerated perfect image of the Mercedes - Benz symbol using R IF...quite often, it cannot be done with a reasonable number of transforms. As an example, the Mercedes Benz symbol generated using an IFS code is illustrated

The Challenge of the Seamless Force: The Role of Informal Networks in Battlespace

DTIC Science & Technology

2005-06-01

10th International Command and Control Research and Technology Symposium THE FUTURE OF C2 Symposium Theme: Lessons Learned Title: The... Technology Organisation Fern Hill Park Department of Defence Canberra ACT 2600 AUSTRALIA Phone +61 2 6256 6219 Fax +61 2 6256 6233...Email Leoni.Warne@dsto.defence.gov.au Derek Bopping Defence Science and Technology Organisation Fern Hill Park Department of Defence Canberra

Mulching to regenerate a harsh site: effect on Douglas-fir seedlings, forbs, grasses, and ferns

Treesearch

Philip M. McDonald; Gary O. Fiddler; Henry R. Harrison

1994-01-01

Douglas-fir seedlings on the Arcata District, Bureau of Land Management, U.S. Department of the Interior, in central coastal California, were planted in an effort to restore the natural forest to what was then pastureland. Douglas-fir seedlings were released from a complex forb-grass-fern plant community by applying very large (10-ft square) and very small (2-foot...

Ferns: the missing link in shoot evolution and development

PubMed Central

Plackett, Andrew R. G.; Di Stilio, Verónica S.; Langdale, Jane A.

2015-01-01

Shoot development in land plants is a remarkably complex process that gives rise to an extreme diversity of forms. Our current understanding of shoot developmental mechanisms comes almost entirely from studies of angiosperms (flowering plants), the most recently diverged plant lineage. Shoot development in angiosperms is based around a layered multicellular apical meristem that produces lateral organs and/or secondary meristems from populations of founder cells at its periphery. In contrast, non-seed plant shoots develop from either single apical initials or from a small population of morphologically distinct apical cells. Although developmental and molecular information is becoming available for non-flowering plants, such as the model moss Physcomitrella patens, making valid comparisons between highly divergent lineages is extremely challenging. As sister group to the seed plants, the monilophytes (ferns and relatives) represent an excellent phylogenetic midpoint of comparison for unlocking the evolution of shoot developmental mechanisms, and recent technical advances have finally made transgenic analysis possible in the emerging model fern Ceratopteris richardii. This review compares and contrasts our current understanding of shoot development in different land plant lineages with the aim of highlighting the potential role that the fern C. richardii could play in shedding light on the evolution of underlying genetic regulatory mechanisms. PMID:26594222

Abscisic acid controlled sex before transpiration in vascular plants

PubMed Central

McAdam, Scott A. M.; Brodribb, Timothy J.; Hedrich, Rainer; Atallah, Nadia M.; Cai, Chao; Geringer, Michael A.; Lind, Christof; Nichols, David S.; Stachowski, Kye; Sussmilch, Frances C.

2016-01-01

Sexual reproduction in animals and plants shares common elements, including sperm and egg production, but unlike animals, little is known about the regulatory pathways that determine the sex of plants. Here we use mutants and gene silencing in a fern species to identify a core regulatory mechanism in plant sexual differentiation. A key player in fern sex differentiation is the phytohormone abscisic acid (ABA), which regulates the sex ratio of male to hermaphrodite tissues during the reproductive cycle. Our analysis shows that in the fern Ceratopteris richardii, a gene homologous to core ABA transduction genes in flowering plants [SNF1-related kinase2s (SnRK2s)] is primarily responsible for the hormonal control of sex determination. Furthermore, we provide evidence that this ABA–SnRK2 signaling pathway has transitioned from determining the sex of ferns to controlling seed dormancy in the earliest seed plants before being co-opted to control transpiration and CO2 exchange in derived seed plants. By tracing the evolutionary history of this ABA signaling pathway from plant reproduction through to its role in the global regulation of plant–atmosphere gas exchange during the last 450 million years, we highlight the extraordinary effect of the ABA–SnRK2 signaling pathway in plant evolution and vegetation function. PMID:27791082

Abscisic acid controlled sex before transpiration in vascular plants.

PubMed

McAdam, Scott A M; Brodribb, Timothy J; Banks, Jo Ann; Hedrich, Rainer; Atallah, Nadia M; Cai, Chao; Geringer, Michael A; Lind, Christof; Nichols, David S; Stachowski, Kye; Geiger, Dietmar; Sussmilch, Frances C

2016-10-26

Sexual reproduction in animals and plants shares common elements, including sperm and egg production, but unlike animals, little is known about the regulatory pathways that determine the sex of plants. Here we use mutants and gene silencing in a fern species to identify a core regulatory mechanism in plant sexual differentiation. A key player in fern sex differentiation is the phytohormone abscisic acid (ABA), which regulates the sex ratio of male to hermaphrodite tissues during the reproductive cycle. Our analysis shows that in the fern Ceratopteris richardii, a gene homologous to core ABA transduction genes in flowering plants [SNF1-related kinase2s (SnRK2s)] is primarily responsible for the hormonal control of sex determination. Furthermore, we provide evidence that this ABA-SnRK2 signaling pathway has transitioned from determining the sex of ferns to controlling seed dormancy in the earliest seed plants before being co-opted to control transpiration and CO 2 exchange in derived seed plants. By tracing the evolutionary history of this ABA signaling pathway from plant reproduction through to its role in the global regulation of plant-atmosphere gas exchange during the last 450 million years, we highlight the extraordinary effect of the ABA-SnRK2 signaling pathway in plant evolution and vegetation function.

The accumulation and subcellular distribution of arsenic and antimony in four fern plants.

PubMed

Feng, R; Wang, X; Wei, C; Tu, S

2015-01-01

In the present study, Pteris cretica 'Albo-Lineata' (PC), Pteris fauriei (PF), Humata tyermanii Moore (HT), and Pteris ensiformis Burm (PE), were selected to explore additional plant materials for the phytoremediation of As and Sb co-contamination. To some extent, the addition of As and Sb enhanced the growth of HT, PE, and PF. Conversely, the addition of As and Sb negatively affected the growth of PC and was accompanied with the accumulation of high levels of As and Sb in the roots. The highest concentration of Sb was recorded as 6405 mg kg(-1) in the roots of PC, and that for As was 337 mg kg(-1) in the rhizome of PF. To some degree, As and Sb stimulated the uptake of each other in these ferns. Arsenic was mainly stored in the cytoplasmic supernatant (CS) fraction, followed by the cell wall (CW) fraction. In contrast, Sb was mainly found in the CW fraction and, to a lesser extent, in the CS fraction, suggesting that the cell wall and cytosol play different roles in As and Sb accumulation by fern plants. This study demonstrated that these fern plants show a good application potential in the phytoremediation of As and Sb co-contaminated environments.

Neural markers of social and monetary rewards in children with Attention-Deficit/Hyperactivity Disorder and Autism Spectrum Disorder.

PubMed

Gonzalez-Gadea, Maria Luz; Sigman, Mariano; Rattazzi, Alexia; Lavin, Claudio; Rivera-Rei, Alvaro; Marino, Julian; Manes, Facundo; Ibanez, Agustin

2016-07-28

Recent theories of decision making propose a shared value-related brain mechanism for encoding monetary and social rewards. We tested this model in children with Attention-Deficit/Hyperactivity Disorder (ADHD), children with Autism Spectrum Disorder (ASD) and control children. We monitored participants' brain dynamics using high density-electroencephalography while they played a monetary and social reward tasks. Control children exhibited a feedback Error-Related Negativity (fERN) modulation and Anterior Cingulate Cortex (ACC) source activation during both tasks. Remarkably, although cooperation resulted in greater losses for the participants, the betrayal options generated greater fERN responses. ADHD subjects exhibited an absence of fERN modulation and reduced ACC activation during both tasks. ASD subjects exhibited normal fERN modulation during monetary choices and inverted fERN/ACC responses in social options than did controls. These results suggest that in neurotypicals, monetary losses and observed disloyal social decisions induced similar activity in the brain value system. In ADHD children, difficulties in reward processing affected early brain signatures of monetary and social decisions. Conversely, ASD children showed intact neural markers of value-related monetary mechanisms, but no brain modulation by prosociality in the social task. These results offer insight into the typical and atypical developments of neural correlates of monetary and social reward processing.

The fern sporangium: an ultrafast natural catapult

NASA Astrophysics Data System (ADS)

Noblin, Xavier; Argentina, Mederic; Westbrook, Jared; Llorens, Coraline; Rojas, Nicolas; Dumais, Jacques

2012-02-01

Plants have developed fascinating mechanisms to create ultra fast movements that often reach the upper limit allowed by physical laws. Inspiration for new technologies is one of the reasons for the strong interest for these mechanisms, along with the deep interest of understanding complex, natural systems. The fern sporangium is a capsule that contains the spores, it is surrounded by a row of cells called the annulus which acts as a beam. Due to the water evaporation from its cells, the annulus bends strongly and induces elastic energy storage during an opening phase. The tension in the cells breaks when cavitation bubbles appear in the cells, leading to a fast release of the elastic energy. The fern sporangium then acts as a catapult which ejects rapidly its spores by closing back to the initial closed shape. We have analyzed the slow opening motion and the fast catapulting mechanism. We found that the catapult motion involves two time scales, showing a very original behavior. In man-made catapults, the recoil motion needs to be arrested by a cross bar so that the projectile is released from the arm. We show here that the fern sporangium replaces the essential cross bar by an elegant poroelastic damping, leading to a completely autonomous, efficient device.

Vascular plant species richness along environmental gradients in a cool temperate to sub-alpine mountainous zone in central Japan.

PubMed

Tsujino, Riyou; Yumoto, Takakazu

2013-03-01

In order to clarify how vegetation types change along the environmental gradients in a cool temperate to sub-alpine mountainous zone and the determinant factors that define plant species richness, we established 360 plots (each 4 × 10 m) within which the vegetation type, species richness, elevation, topographic position index (TPI), slope inclination, and ground light index (GLI) of the natural vegetation were surveyed. Mean elevation, TPI, slope inclination, and GLI differed across vegetation types. Tree species richness was negatively correlated with elevation, whereas fern and herb species richness were positively correlated. Tree species richness was greater in the upper slope area than the lower slope area, whereas fern and herb species richness were greater in the lower slope area. Ferns and trees species richness were smaller in the open canopy, whereas herb species richness was greater in the open canopy. Vegetation types were determined firstly by elevation and secondary by topographic configurations, such as topographic position, and slope inclination. Elevation and topography were the most important factors affecting plant richness, but the most influential variables differed among plant life-form groups. Moreover, the species richness responses to these environmental gradients greatly differed among ferns, herbs, and trees.

Phylogeny of marattioid ferns (Marattiaceae): inferring a root in the absence of a closely related outgroup.

PubMed

Murdock, Andrew G

2008-05-01

Closely related outgroups are optimal for rooting phylogenetic trees; however, such ideal outgroups are not always available. A phylogeny of the marattioid ferns (Marattiaceae), an ancient lineage with no close relatives, was reconstructed using nucleotide sequences of multiple chloroplast regions (rps4 + rps4-trnS spacer, trnS-trnG spacer + trnG intron, rbcL, atpB), from 88 collections, selected to cover the broadest possible range of morphologies and geographic distributions within the extant taxa. Because marattioid ferns are phylogenetically isolated from other lineages, and internal branches are relatively short, rooting was problematic. Root placement was strongly affected by long-branch attraction under maximum parsimony and by model choice under maximum likelihood. A multifaceted approach to rooting was employed to isolate the sources of bias and produce a consensus root position. In a statistical comparison of all possible root positions with three different outgroups, most root positions were not significantly less optimal than the maximum likelihood root position, including the consensus root position. This phylogeny has several important taxonomic implications for marattioid ferns: Marattia in the broad sense is paraphyletic; the Hawaiian endemic Marattia douglasii is most closely related to tropical American taxa; and Angiopteris is monophyletic only if Archangiopteris and Macroglossum are included.

Neoendemism in Madagascan scaly tree ferns results from recent, coincident diversification bursts.

PubMed

Janssen, Thomas; Bystriakova, Nadia; Rakotondrainibe, France; Coomes, David; Labat, Jean-Noël; Schneider, Harald

2008-08-01

More than 80% of Madagascar's 12,000 plant species are endemic with the degree of endemism reaching as much as 95% in the scaly tree ferns, an important species rich component of Madagascar's evergreen rainforests. Predominantly African or Asian ancestry and divergence times usually postdating the separation of Madagascar from the Gondwanan landmasses have been demonstrated for several Madagascan animal and angiosperm groups. However, evolutionary studies of rainforest-specific lineages are scarce and the ecological context of radiation events has rarely been investigated. Here, we examine the evolution of Madagascan tree ferns as a rainforest-specific model family, integrate results from bioclimatic niche analysis with a dated phylogenetic framework, and propose an evolutionary scenario casting new light on our knowledge of the evolution of large island endemic clades. We show that Madagascar's extant tree fern diversity springs from three distinct ancestors independently colonizing Madagascar in the Miocene and that these three monophyletic clades diversified in three coincident radiation bursts during the Pliocene, reaching exceptionally high diversification rates and most likely responding to a common climatic trigger. Recent diversification bursts may thus have played a major role in the evolution of the extant Madagascan rainforest biome, which hence contains a significant number of young, neoendemic taxa.

2005 Tri-Service Infrastructure Systems Conference and Exhibition. Volume 5, Track 5

DTIC Science & Technology

2005-08-04

Patrick O’Brien and David Biedenharn Watershed Approach to Stream Stability and Benefits Related to the Reduction of Nutrients, by John B. Smith A Lake ...J.B. Smith and Randall A. Wise Bluff Stabilization along Lake Michigan, using Active and Passive Dewatering Techniques, by Rennie Kaunda, Eileen...Sacred Falls, Oahsacred Falls, Oahu Section 227 Demonstration Project Track 4 Fern Ridge LakFern Ridge Lake Hydrologic Aspects of Operation during Failure

Actions to Abate Critical Threats, Such as Encroachment and Invasive Species, Using GIS and Conservation Area Planning Across the Gulf Coastal Plain Ecosystem Partnership (GCPEP) Landscape, Phase 1

DTIC Science & Technology

2006-12-22

invasive species include cogongrass ( Imperata cylindrica ), Chinese tallowtree (Sapium sebiferum), Japanese climbing fern (Lygodium japonicum), Chinese...Species in bold letter were identified as the top invasives across the partnership. Plants Animals 10 Cogon Grass( Imperata cylindrica ) 10...problematic invasive species include cogongrass ( Imperata cylindrica ), Chinese tallowtree (Sapium sebiferum), Japanese climbing fern (Lygodium japonicum

Diterpenoid glycosides from the bitter fern Gleichenia quadripartita.

PubMed

Socolsky, Cecilia; Asakawa, Yoshinori; Bardón, Alicia

2007-12-01

Fifteen new diterpenoid glycosides (1a-n, 2) were isolated from an Argentine collection of the bitter fern Gleichenia quadripartita along with the known flavonoid glycoside afzelin. Structure elucidation was accomplished by 1D and 2D NMR spectroscopy and by high-resolution MS analyses. In addition, X-ray crystallographic analysis of a monocrystal of 1a as well as chemical derivatization of 1h and 1m were performed to confirm their structures.

Stomatal innovation and the rise of seed plants.

PubMed

McAdam, Scott A M; Brodribb, Timothy J

2012-01-01

Stomatal valves on the leaves of vascular plants not only prevent desiccation but also dynamically regulate water loss to maintain efficient daytime water use. This latter process involves sophisticated active control of stomatal aperture that may be absent from early-branching plant clades. To test this hypothesis, we compare the stomatal response to light intensity in 13 species of ferns and lycophytes with a diverse sample of seed plants to determine whether the capacity to optimise water use is an ancestral or derived feature of stomatal physiology. We found that in seed plants, the ratio of photosynthesis to water use remained high and constant at different light intensities, but fern and lycophyte stomata were incapable of sustaining homeostatic water use efficiency. We conclude that efficient water use in early seed plants provided them with a competitive advantage that contributed to the decline of fern and lycophyte dominated-ecosystems in the late Paleozoic. © 2011 Blackwell Publishing Ltd/CNRS.

Modelling phytoremediation by the hyperaccumulating fern, Pteris vittata, of soils historically contaminated with arsenic.

PubMed

Shelmerdine, Paula A; Black, Colin R; McGrath, Steve P; Young, Scott D

2009-05-01

Pteris vittata plants were grown on twenty-one UK soils contaminated with arsenic (As) from a wide range of natural and anthropogenic sources. Arsenic concentration was measured in fern fronds, soil and soil pore water collected with Rhizon samplers. Isotopically exchangeable soil arsenate was determined by equilibration with (73)As(V). Removal of As from the 21 soils by three sequential crops of P. vittata ranged between 0.1 and 13% of total soil As. Ferns grown on a soil subjected to long-term sewage sludge application showed reduced uptake of As because of high available phosphate concentrations. A combined solubility-uptake model was parameterised to enable prediction of phytoremediation success from estimates of soil As, 'As-lability' and soil pH. The model was used to demonstrate the remediation potential of P. vittata under different soil conditions and with contrasting assumptions regarding re-supply of the labile As pool from unavailable forms.

The late Cretaceous Arman flora of Magadan oblast, Northeastern Russia

NASA Astrophysics Data System (ADS)

Herman, A. B.; Golovneva, L. B.; Shczepetov, S. V.; Grabovsky, A. A.

2016-12-01

The Arman flora from the volcanogenic-sedimentary beds of the Arman Formation is systematically studied using materials from the Arman River basin and the Nelkandya-Khasyn interfluve (Magadan oblast, Northeastern Russia). Seventy-three species of fossil plants belonging to 49 genera are described. They consist of liverworts, horsetails, ferns, seed ferns, cycadaleans, bennettitaleans, ginkgoaleans, czekanowskialeans, conifers, gymnosperms of uncertain systematic affinity, and angiosperms. The Arman flora shows a unique combination, with relatively ancient Early Cretaceous ferns and gymnosperms occurring alongside younger Late Cretaceous plants, primarily angiosperms. The similarity of the Arman flora to the Penzhina and Kaivayam floras of northwestern Kamchatka and the Tylpegyrgynai flora of the Pekul'nei Ridge allows the Arman flora to be dated as Turonian and Coniacian (Late Cretaceous), which is corroborated by isotopic (U-Pb and 40Ar/39Ar) age determination for the plant-bearing layers.

Response of nitrogen-fixing water fern Azolla biofertilization to rice crop.

PubMed

Bhuvaneshwari, K; Singh, Pawan Kumar

2015-08-01

The water fern Azolla harbors nitrogen-fixing cyanobacterium Anabaena azollae as symbiont in its dorsal leaves and is known as potent N 2 fixer. Present investigation was carried out to study the influence of fresh Azolla when used as basal incorporation in soil and as dual cropped with rice variety Mahsoori separately and together with and without chemical nitrogen fertilizer in pots kept under net house conditions. Results showed that use of Azolla as basal or dual or basal plus dual influenced the rice crop positively where use of fern as basal plus dual was superior and served the nitrogen requirement of rice. There was marked increase in plant height, number of effective tillers, dry mass and nitrogen content of rice plants with the use of Azolla and N-fertilizers alone and other combinations. The use of Azolla also increased organic matter and potassium contents of the soil.

Risk-Taking and the Feedback Negativity Response to Loss among At-Risk Adolescents

PubMed Central

Crowley, Michael J.; Wu, Jia; Crutcher, Clifford; Bailey, Christopher A.; Lejuez, C.W.; Mayes, Linda C.

2009-01-01

Event-related brain potentials were examined in 32 adolescents (50% female) from a high-risk sample, who were exposed to cocaine and other drugs prenatally. Adolescents were selected for extreme high- or low-risk behavior on the Balloon Analog Risk Task, a measure of real-world risk-taking propensity. The feedback error-related negativity (fERN), an event-related potential (ERP) that occurs when an expected reward does not occur, was examined in a game in which choices lead to monetary gains and losses with feedback delayed 1 or 2 s. The fERN was clearly visible in the fronto-central scalp region in this adolescent sample. Feedback type, feedback delay, risk status, and sex were all associated with fERN variability. Monetary feedback also elicited a P300-like component, moderated by delay and sex. Delaying reward feedback may provide a means for studying complementary functioning of dopamine and norepinephrine systems. PMID:19372694

Cross-Cultural Awareness. Concept

DTIC Science & Technology

2010-11-01

Dirección de Investigación, Doctrina, Orgánica y Materiales ], 18071 Granada, Spain 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING...Organization and Materiel [Dirección de Investigación, Doctrina, Orgánica y Materiales ], Attn: Maj José Fernández-Alfaro, San Idelfonso s/n 18071 Granada...Doctrine, Organization and Materiel [Dirección de Investigación, Doctrina, Orgánica y Materiales ] Attn: Maj José Fernández-Alfaro San Idelfonso

Rates of ecological divergence and body size evolution are correlated with species diversification in scaly tree ferns

PubMed Central

Ramírez-Barahona, Santiago; Barrera-Redondo, Josué; Eguiarte, Luis E.

2016-01-01

Variation in species richness across regions and between different groups of organisms is a major feature of evolution. Several factors have been proposed to explain these differences, including heterogeneity in the rates of species diversification and the age of clades. It has been frequently assumed that rapid rates of diversification are coupled to high rates of ecological and morphological evolution, leading to a prediction that remains poorly explored for most species: the positive association between ecological niche divergence, morphological evolution and species diversification. We combined a time-calibrated phylogeny with distribution, ecological and body size data for scaly tree ferns (Cyatheaceae) to test whether rates of species diversification are predicted by the rates at which clades have evolved distinct ecological niches and body sizes. We found that rates of species diversification are positively correlated with rates of ecological and morphological evolution, with rapidly diversifying clades also showing rapidly evolving ecological niches and body sizes. Our results show that rapid diversification of scaly tree ferns is associated with the evolution of species with comparable morphologies that diversified into similar, yet distinct, environments. This suggests parallel evolutionary pathways opening in different tropical regions whenever ecological and geographical opportunities arise. Accordingly, rates of ecological niche and body size evolution are relevant to explain the current patterns of species richness in this ‘ancient’ fern lineage across the tropics. PMID:27412279

Not dead yet: the seasonal water relations of two perennial ferns during California's exceptional drought.

PubMed

Baer, Alex; Wheeler, James K; Pittermann, Jarmila

2016-04-01

The understory of the redwood forests of California's coast harbors perennial ferns, including Polystichum munitum and Dryopteris arguta. Unusual for ferns, these species are adapted to the characteristic Mediterranean-type dry season, but the mechanisms of tolerance have not been studied. The water relations of P. munitum and D. arguta were surveyed for over a year, including measures of water potential (Ψ), stomatal conductance (gs) and frond stipe hydraulic conductivity (K). A dehydration and re-watering experiment on potted P. munitum plants corroborated the field data. The seasonal Ψ varied from 0 to below -3 MPa in both species, with gs and K generally tracking Ψ; the loss of K rarely exceeded 80%. Quantile regression analysis showed that, at the 0.1 quantile, 50% of K was lost at -2.58 and -3.84 MPa in P. munitum and D. arguta, respectively. The hydraulic recovery of re-watered plants was attributed to capillarity. The seasonal water relations of P. munitum and D. arguta are variable, but consistent with laboratory-based estimates of drought tolerance. Hydraulic and Ψ recovery following rain allows perennial ferns to survive severe drought, but prolonged water deficit, coupled with insect damage, may hamper frond survival. The legacy effects of drought on reproductive capacity and community dynamics are unknown. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

Rates of ecological divergence and body size evolution are correlated with species diversification in scaly tree ferns.

PubMed

Ramírez-Barahona, Santiago; Barrera-Redondo, Josué; Eguiarte, Luis E

2016-07-13

Variation in species richness across regions and between different groups of organisms is a major feature of evolution. Several factors have been proposed to explain these differences, including heterogeneity in the rates of species diversification and the age of clades. It has been frequently assumed that rapid rates of diversification are coupled to high rates of ecological and morphological evolution, leading to a prediction that remains poorly explored for most species: the positive association between ecological niche divergence, morphological evolution and species diversification. We combined a time-calibrated phylogeny with distribution, ecological and body size data for scaly tree ferns (Cyatheaceae) to test whether rates of species diversification are predicted by the rates at which clades have evolved distinct ecological niches and body sizes. We found that rates of species diversification are positively correlated with rates of ecological and morphological evolution, with rapidly diversifying clades also showing rapidly evolving ecological niches and body sizes. Our results show that rapid diversification of scaly tree ferns is associated with the evolution of species with comparable morphologies that diversified into similar, yet distinct, environments. This suggests parallel evolutionary pathways opening in different tropical regions whenever ecological and geographical opportunities arise. Accordingly, rates of ecological niche and body size evolution are relevant to explain the current patterns of species richness in this 'ancient' fern lineage across the tropics. © 2016 The Author(s).

Neural markers of social and monetary rewards in children with Attention-Deficit/Hyperactivity Disorder and Autism Spectrum Disorder

PubMed Central

Gonzalez-Gadea, Maria Luz; Sigman, Mariano; Rattazzi, Alexia; Lavin, Claudio; Rivera-Rei, Alvaro; Marino, Julian; Manes, Facundo; Ibanez, Agustin

2016-01-01

Recent theories of decision making propose a shared value-related brain mechanism for encoding monetary and social rewards. We tested this model in children with Attention-Deficit/Hyperactivity Disorder (ADHD), children with Autism Spectrum Disorder (ASD) and control children. We monitored participants’ brain dynamics using high density-electroencephalography while they played a monetary and social reward tasks. Control children exhibited a feedback Error-Related Negativity (fERN) modulation and Anterior Cingulate Cortex (ACC) source activation during both tasks. Remarkably, although cooperation resulted in greater losses for the participants, the betrayal options generated greater fERN responses. ADHD subjects exhibited an absence of fERN modulation and reduced ACC activation during both tasks. ASD subjects exhibited normal fERN modulation during monetary choices and inverted fERN/ACC responses in social options than did controls. These results suggest that in neurotypicals, monetary losses and observed disloyal social decisions induced similar activity in the brain value system. In ADHD children, difficulties in reward processing affected early brain signatures of monetary and social decisions. Conversely, ASD children showed intact neural markers of value-related monetary mechanisms, but no brain modulation by prosociality in the social task. These results offer insight into the typical and atypical developments of neural correlates of monetary and social reward processing. PMID:27464551

Phytoextraction and accumulation of mercury in three plant species: Indian mustard (Brassica juncea), beard grass (Polypogon monospeliensis), and Chinese brake fern (Pteris vittata).

PubMed

Su, Yi; Han, Fengxiang X; Chen, Jian; Sridhar, B B Maruthi; Monts, David L

2008-01-01

The objective of this research was to screen and search for suitable plant species to phytoextract mercury-contaminated soil. Our effort focused on using some of the known metal-accumulating wild-type plants since no natural plant species with mercury-hyperaccumulat ing properties has yet been identified. Three plant species were evaluated for their uptake efficiency for mercury: Indian mustard (Brassica juncea), beard grass (Polypogon monospeliensis), and Chinese brake fern (Pteris vittata). Four sets of experiments were conducted to evaluate the phytoremediation potential of these three plant species: a pot study with potting mix where mercury was provided daily as HgCl2 solution; experiments with freshly mercury-spiked soil; and a study with aged soils contaminated with different mercury sources (HgCl2, Hg(NO3)2, and HgS). Homemade sunlit chambers were also used to study foliar uptake of Hg from ambient air. Among the three plant species, Chinese brake fern showed the least stress symptoms resulting from mercury exposure and had the highest mercury accumulation. Our results indicate that Chinese brake fern may be a potential candidate for mercury phytoextraction. We found that mercury contamination is biologically available for plant uptake and accumulation, even if the original and predominating mercury form is HgS, and also after multiple phytoremediation cycles.

Inventory of Rare or Endangered Non-Vascular Plants and Ferns Occurring in the Floodplain of the Mississippi River between Cairo, Illinois, and St. Paul, Minnesota, and in the Floodplain of the Illinois River between Grafton, Illinois, and Chicago,

DTIC Science & Technology

1975-02-03

3 Liverworts and Horworts ------------------ 4 Lichens -------------------------------- 4 Ferns ------------------------------- 5 Algae of the...Mississippi River and Illinois River Floodplains ----- 6 Mosses of the Mississippi River and Illinois River Floodplains--- 35 Liverworts and Hornworts...any alga, hornwort, liverwort , moss, or lichen in the study area. Missouri (1974) lists some mosses which are designated 0 rare or endangered, but

Response to the Fernández-Niño Comments on Hernández-Alvarado et al. Increase in Suicide Rates by Hanging in the Population of Tabasco, México between 2003 and 2012. Int. J. Environ. Res. Public Health 2016, 13, 552.

PubMed

Hernández-Alvarado, Mervyn Manuel; González-Castro, Thelma Beatriz; Tovilla-Zárate, Carlos Alfonso; Fresán, Ana; Juárez-Rojop, Isela E; López-Narváez, María Lilia; Villar-Soto, Mario; Genis-Mendoza, Alma

2016-07-01

We thank the comments of Fernández-Niño [1] addressing our article [2] "Increase in Suicide Rates by Hanging in the Population of Tabasco, Mexico between 2003 and 2012", which pointed out that the use of the epidemiological concept "prevalence" is not correctly applied in the present manuscript.

Let's get physical!: Comment on" Physical methods for genetic transformation of fungi and yeast" by Ana L. Rivera, Denis Magaña-Ortíz, Miguel Gómez-Lim, Francisco Fernández and Achim M. Loske.

USDA-ARS?s Scientific Manuscript database

This comment analyses the paper “Physical methods for genetic transformation of fungi and yeast” by Ana L. Rivera, Denis Magaña-Ortíz , Miguel Gómez-Lim , Francisco Fernández and Achim M. Loske. I examine the methods described and their advantages and disadvantages. I further discuss the other more ...

Comparison of the petrography, palynology, and paleobotany of the Little Fire Creek coal bed, southwestern Virginia, USA

USGS Publications Warehouse

Pierce, B.S.; Eble, C.F.; Stanton, R.W.

1995-01-01

The proximate, petrographic, palynologic, and plant tissue data from two sets of samples indicate a high ash, gelocollinite- and liptinite-rich coal consisting of a relatively diverse paleoflora, including lycopsid trees, small lycopsids, tree ferns, small ferns, pteridosperms, and rare calamites and cordaites. The relatively very high ash yields the relatively thin subunits and the large scale vertical variations in palynomorph floras suggest that the study area was at the edge of the paleopeat-forming environment. -from Authors

Intramolecular co-action of two independent photosensory modules in the fern phytochrome 3.

PubMed

Kanegae, Takeshi

2015-01-01

Fern phytochrome3/neochrome1 (phy3/neo1) is a chimeric photoreceptor composed of a phytochrome-chromophore binding domain and an almost full-length phototropin. phy3 thus contains two different light-sensing modules; a red/far-red light receptor phytochrome and a blue light receptor phototropin. phy3 induces both red light- and blue light-dependent phototropism in phototropin-deficient Arabidopsis thaliana (phot1 phot2) seedlings. The red-light response is dependent on the phytochrome module of phy3, and the blue-light response is dependent on the phototropin module. We recently showed that both the phototropin-sensing module and the phytochrome-sensing module mediate the blue light-dependent phototropic response. Particularly under low-light conditions, these two light-sensing modules cooperate to induce the blue light-dependent phototropic response. This intramolecular co-action of two independent light-sensing modules in phy3 enhances light sensitivity, and perhaps allowed ferns to adapt to the low-light canopy conditions present in angiosperm forests.

A new fossil fern assignable to Gleicheniaceae from Late Cretaceous sediments of New Jersey.

PubMed

Gandolfo, M; Nixon, K; Crepet, W; Ratcliffe, G

1997-04-01

The recent discovery of well-preserved charcoalified rhizomes, petioles. pinnules, sori, and spores from the Upper Cretaceous of New Jersey provides the basis for the description of a new gleicheniaceous fern, Boodlepteris turoniana. The fossils were collected from unconsolidated sediments of Turonian age (~90 MYBP million years before present; Raritan/ Lower Magothy Formation, Potomac Group). These deposits are rich in angiosperms, but also have a limited representation of fern and gymnosperm remains. Fossil specimens from this locality are particularly remarkable in that minute detail, including anatomical features, are often preserved. Some Boodlepteris specimens have cell by cell preservation that reveals the nature and structure of the stele in rhizomes and petioles, and others show minute details of the sori borne on fertile pinnae. Although these specimens are not in organic connection, there are sufficient structural and anatomical details preserved to confidently suggest that they belong to the same taxon. Cladistic analysis of the fossils, both separately and as a reconstruction, support assignment of Boodlepteris to the extant family Gleicheniaceae.

Arsenic accumulation by the aquatic fern Azolla: comparison of arsenate uptake, speciation and efflux by A. caroliniana and A. filiculoides.

PubMed

Zhang, Xin; Lin, Ai-Jun; Zhao, Fang-Jie; Xu, Guo-Zhong; Duan, Gui-Lan; Zhu, Yong-Guan

2008-12-01

This study investigates As accumulation and tolerance of the aquatic fern Azolla. Fifty strains of Azolla showed a large variation in As accumulation. The highest- and lowest-accumulating ferns among the 50 strains were chosen for further investigations. Azolla caroliniana accumulated two times more As than Azolla filiculoides owing to a higher influx velocity for arsenate. A. filiculoides was more resistant to external arsenate due to a lower uptake. Both strains showed a similar degree of tolerance to internal As. Arsenate and arsenite were the dominant As species in both Azolla strains, with methylated As species accounting for <5% of the total As. A. filiculoides had a higher proportion of arsenite than A. caroliniana. Both strains effluxed more arsenate than arsenite, and the amount of As efflux was proportional to the amount of As accumulation. The potential of growing Azolla in paddy fields to reduce As transfer from soil and water to rice should be further evaluated.

Complex rheological properties of a water-soluble extract from the fronds of the black tree fern, Cyathea medullaris.

PubMed

Goh, Kelvin K T; Matia-Merino, Lara; Hall, Christopher E; Moughan, Paul J; Singh, Harjinder

2007-11-01

A water-soluble extract was obtained from the fronds of a New Zealand native black tree fern (Cyathea medullaris or Mamaku in Māori). The extract exhibited complex rheological behavior. Newtonian, shear-thinning, shear-thickening, thixotropic, antithixotropic, and viscoelastic behaviors were observed depending on polymer concentration, shear rate, and shear history. The extract also displayed rod-climbing and self-siphoning properties typical of viscoelastic fluids. Such complex rheological properties have been reported in synthetic or chemically modified polymers but are less frequent in unmodified biopolymers. Although Mamaku extract obtained from the pith of the fern has been traditionally used by the Māori in New Zealand for treating wounds and diarrhea among other ailments, this material has never been characterized before. This study reports on the chemical composition of the extract and on its viscoelastic properties through rotational and oscillatory rheological measurements. Explanations of the mechanism behind the rheological properties were based on transient network models for associating polymers.

The effect of different growth regimes on the endophytic bacterial communities of the fern, Dicksonia sellowiana hook (Dicksoniaceae).

PubMed

de Araújo Barros, Irene; Luiz Araújo, Welington; Lúcio Azevedo, João

2010-10-01

Endophytic bacteria associated with the fern Dicksonia sellowiana were investigated. The bacterial communities from the surface-sterilized pinnae and rachis segments of the plants from the Brazilian Atlantic Rainforest that grew in native field conditions were compared with the bacterial communities from plants grown in greenhouses and plants that were initially grown in greenhouses and then transferred to the forest. From 540 pinnae and 540 rachis segments, 163 (30.2%) and 346 (64.2%) were colonized by bacteria, respectively. The main bacterial genera and species that were isolated included Bacillus spp. ( B. cereus, B. megaterium, B. pumilus and B. subtilis ) , Paenibacillus sp. , Amphibacillus sp. , Gracilibacillus sp. , Micrococcus sp. and Stenotrophomonas spp. ( S. maltophilia and S. nitroreducens ). B. pumilus was the most frequently isolated bacterial species . Amphibacillus and Gracilibacillus were reported as endophytes for the first time. Other commonly found bacterial genera were not observed in D. sellowiana , which may reflect preferences of specific bacterial communities inside this fern or detection limitations due to the isolation procedures. Plants that were grown in greenhouses and plants that were reintroduced into the forest displayed more bacterial genera and species diversity than native field plants, suggesting that reintroduction shifts the bacterial diversity. Endophytic bacteria that displayed antagonistic properties against different microorganisms were detected, but no obvious correlation was found between their frequencies with plant tissues or with plants from different growth regimes. This paper reports the first isolation of endophytic bacteria from a fern.

The effect of different growth regimes on the endophytic bacterial communities of the fern, Dicksonia sellowiana hook (Dicksoniaceae)

PubMed Central

de Araújo Barros, Irene; Luiz Araújo, Welington; Lúcio Azevedo, João

2010-01-01

Endophytic bacteria associated with the fern Dicksonia sellowiana were investigated. The bacterial communities from the surface-sterilized pinnae and rachis segments of the plants from the Brazilian Atlantic Rainforest that grew in native field conditions were compared with the bacterial communities from plants grown in greenhouses and plants that were initially grown in greenhouses and then transferred to the forest. From 540 pinnae and 540 rachis segments, 163 (30.2%) and 346 (64.2%) were colonized by bacteria, respectively. The main bacterial genera and species that were isolated included Bacillus spp. ( B. cereus, B. megaterium, B. pumilus and B. subtilis ) , Paenibacillus sp. , Amphibacillus sp. , Gracilibacillus sp. , Micrococcus sp. and Stenotrophomonas spp. ( S. maltophilia and S. nitroreducens ). B. pumilus was the most frequently isolated bacterial species . Amphibacillus and Gracilibacillus were reported as endophytes for the first time. Other commonly found bacterial genera were not observed in D. sellowiana , which may reflect preferences of specific bacterial communities inside this fern or detection limitations due to the isolation procedures. Plants that were grown in greenhouses and plants that were reintroduced into the forest displayed more bacterial genera and species diversity than native field plants, suggesting that reintroduction shifts the bacterial diversity. Endophytic bacteria that displayed antagonistic properties against different microorganisms were detected, but no obvious correlation was found between their frequencies with plant tissues or with plants from different growth regimes. This paper reports the first isolation of endophytic bacteria from a fern. PMID:24031575

Phytoextraction: simulating uptake and translocation of arsenic in a soil-plant system.

PubMed

Ouyang, Ying

2005-01-01

The uptake, transport, and accumulation of metals by plants are functions central to successful phytoextraction. This study investigates the uptake and translocation of arsenic from a contaminated sandy soil by a mature Chinese brake fern (Pteris vittata L.). An existing mathematical model for the coupled transport of water, heat, and solutes in the soil-plant-atmosphere continuum (CTSPAC) was modified to examine the flow of water as well as the uptake and translocation of total arsenic in the xylem of the fern. This model was calibrated using greenhouse measurements before its application. Simulation results showed that about 20% of the soil arsenic was removed by the fern in 10 d, of which about 90% of the arsenic was stored in the fronds and 10% in the roots. Although arsenic mass in the plant tissues increased consecutively with time, arsenic concentration in the xylem sap of the root tips has a typical diurnal distribution pattern: increasing during the day and decreasing at night, resulting from daily variations of frond surface water transpiration. The largest difference in simulated arsenic concentration in the root tips between the day and night was about 5%. This study also suggests that the use of transpiration stream concentration factor (TSCF), which is defined as the ratio of chemical concentration in the xylem sap to that in the external solution, to evaluate the translocation efficiency of arsenic for the hyperaccumulator Chinese brake fern (Pteris vittata L.) could be limited.

Ecological response of plant consumers to Middle-Upper Pennsylvanian extinctions in Illinois Basin coal swamps: Evidence from plant/arthropod interactions

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

Labandeira, C.; Phillips, T.

1992-01-01

Paleobotanical studies of coal-swamp vegetation during the Middle to Upper Pennsylvanian of North America indicate major changes from lycopsid dominated to tree-fern dominated coal-swamp forests as a result of extinction. This taxonomic shift from lycopsids to tree ferns should have implications on dependent feeding guilds, such as detritivores and herbivores. Comparative coal-ball evidence from the Springfield and Herrin Coals (Carbondale Fm.) and Calhoun Coal (Mattoon Fm.) is used to address this issue. The two major feeding guilds of Pennsylvanian coal-swamps were detritivores and herbivores. Detritivores were dominant throughout the interval. Evidence suggests an increasing presence of herbivores during the Desmoinesianmore » and especially during the Missourian. Based on identifications of tissue types found in coprolite types and plant tissue damage patterns, detritivores such as oribatid mites and an unknown stem-parenchyma consumer of Psaronius tree ferns occur before and after the extinction. Based on available evidence, detritivores apparently exhibited stability, particularly since the taxonomic affiliation of their food resource shifted considerably, thus indicating dietary specificities based instead on tissue type. There is evidence for herbivory by stem-miners on Missourian age tree-fern petioles; this distinctive behavior has not been reported for Desmoinesean or older deposits. The arthropod body-fossil record is consistent with this pattern: detritivore groups such as roaches survive the extinction largely intact, whereas other groups such as diverse protorthopterans,'' some of which were most likely herbivorous, experienced a significant extinction.« less

[Presence, abundance and reproductive strategies of ferns in disturbed areas of Sierra Nevada, México].

PubMed

Rodríguez Romero, Ma Lucía; Zavala Hurtado, José Alejandro; Pacheco, Leticia

2011-03-01

Diverse reproductive strategies shown by ferns and lycophytes allow them to colonize a variety of habitats, particularly after the incidence of natural or anthropogenic disturbances. This study assessed the presence, abundance and reproductive strategies of ferns growing in soils of temperate forests with different levels of disturbance at the Sierra Nevada mountain range in the State of Mexico. Vegetation, soil and environmental variables were recorded in 200 m2 permanent plots located in four forest stands. One-Way ANOVA and Canonical Correspondence Analysis resulted in the recognition of three landscape types defined by the degree of environmental alteration: low, moderate and severe. Also, from five soil samples collected in each stand, germination of ferns and lycophytes was induced. A positive relationship was found between the alteration degree and Cheilanthes abundance. Under a low landscape alteration regime, species richness is restricted to Cheilanthes bonariensis, C. marginata and Pellaea ternifolia subsp. ternifolia. The soil is a reservoir of spores of Cheilanthes and Pellaea ternifolia subsp. ternifolia because their spores can remain viable for different time intervals. Apogamy is the usual reproductive strategy of Cheilanthes species in disturbed ecosystems, although these species also show sexual reproduction in natural ecosystems with adequate water availability. Apogamy may be related to a shorter generation time in comparison with a low disturbed ecosystem. On the other hand, Pellaea ternifolia subsp. ternifolia only has sexual reproduction. Apogamy might be related to a faster generation in comparison with a low disturbed ecosystem.

Remote sensing investigations of fugitive soil arsenic and its effects on vegetation reflectance

NASA Astrophysics Data System (ADS)

Slonecker, E. Terrence

2007-12-01

Three different remote sensing technologies were evaluated in support of the remediation of fugitive arsenic and other hazardous waste-related risks to human and ecological health at the Spring Valley Formerly Used Defense Site in northwest Washington D.C., an area of widespread soil arsenic contamination as a result of World War I research and development of chemical weapons. The first evaluation involved the value of information derived from the interpretation of historical aerial photographs. Historical aerial photographs dating back as far as 1918 provided a wealth of information about chemical weapons testing, storage, handling and disposal of these hazardous materials. When analyzed by a trained photo-analyst, the 1918 aerial photographs resulted in 42 features of potential interest. When compared with current remedial activities and known areas of contamination, 33 of 42 or 78.5 % of the features were spatially correlated with current areas of contamination or remedial activity. The second investigation involved the phytoremediation of arsenic through the use of Pteris ferns and the evaluation of the spectral properties of these ferns. Three hundred ferns were grown in controlled laboratory conditions in soils amended with five levels (0, 20, 50, 100 and 200 parts per million) of sodium arsenate. After 20 weeks, the Pteris ferns were shown to have an average uptake concentration of over 4,000 parts per million each. Additionally, statistical analysis of the spectral signature from each fern showed that the frond arsenic concentration could be reasonably predicted with a linear model when the concentration was equal or greater than 500 parts per million. Third, hyperspectral imagery of Spring Valley was obtained and analyzed with a suite of spectral analysis software tools. Results showed the grasses growing in areas of known high soil arsenic could be identified and mapped at an approximate 85% level of accuracy when the hyperspectral image was processed with a linear spectral unmixing algorithm and mapped with a maximum likelihood classifier. The information provided by these various remote sensing technologies presents a non-contact and potentially important alternative to the information needs of the hazardous waste remediation process, and is an important area for future environmental research.

Stomatal and mesophyll conductances to CO₂ in different plant groups: underrated factors for predicting leaf photosynthesis responses to climate change?

PubMed

Flexas, Jaume; Carriquí, Marc; Coopman, Rafael E; Gago, Jorge; Galmés, Jeroni; Martorell, Sebastià; Morales, Fermín; Diaz-Espejo, Antonio

2014-09-01

The climate change conditions predicted for the end of the current century are expected to have an impact on the performance of plants under natural conditions. The variables which are foreseen to have a larger effect are increased CO2 concentration and temperature. Although it is generally considered CO2 assimilation rate could be increased by the increasing levels of CO2, it has been reported in previous studies that acclimation to high CO2 results in reductions of physiological parameters involved in photosynthesis, like the maximum carboxylation rate (Vc,max), stomatal conductance (gs) and mesophyll conductance to CO2 (gm). On the one hand, most of the previous modeling efforts have neglected the potential role played by the acclimation of gm to high CO2 and temperature. On the other hand, the effect of climate change on plant clades other than angiosperms, like ferns, has received little attention, and there are no studies evaluating the potential impact of increasing CO2 and temperature on these species. In this study we predicted responses of several representative species among angiosperms, gymnosperms and ferns to increasing CO2 and temperature. Our results show that species with lower photosynthetic capacity - such as some ferns and gymnosperms - would be proportionally more favored under these foreseen environmental conditions. The main reason for this difference is the lower diffusion limitation imposed by gs and gm in plants having high capacity for photosynthesis among the angiosperms, which reduces the positive effect of increasing CO2. However, this apparent advantage of low-diffusion species would be canceled if the two conductances - gs and gm - acclimate and are down regulated to high CO2, which is basically unknown, especially for gymnosperms and ferns. Hence, for a better understanding of different plant responses to future climate, studies are urged in which the actual photosynthetic response/acclimation to increased CO2 and temperature of ferns, gymnosperms and other under-evaluated plant groups is assessed. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Molecular evolution of psbA gene in ferns: unraveling selective pressure and co-evolutionary pattern

PubMed Central

2012-01-01

Background The photosynthetic oxygen-evolving photo system II (PS II) produces almost the entire oxygen in the atmosphere. This unique biochemical system comprises a functional core complex that is encoded by psbA and other genes. Unraveling the evolutionary dynamics of this gene is of particular interest owing to its direct role in oxygen production. psbA underwent gene duplication in leptosporangiates, in which both copies have been preserved since. Because gene duplication is often followed by the non-fictionalization of one of the copies and its subsequent erosion, preservation of both psbA copies pinpoint functional or regulatory specialization events. The aim of this study was to investigate the molecular evolution of psbA among fern lineages. Results We sequenced psbA , which encodes D1 protein in the core complex of PSII, in 20 species representing 8 orders of extant ferns; then we searched for selection and convolution signatures in psbA across the 11 fern orders. Collectively, our results indicate that: (1) selective constraints among D1 protein relaxed after the duplication in 4 leptosporangiate orders; (2) a handful positively selected codons were detected within species of single copy psbA, but none in duplicated ones; (3) a few sites among D1 protein were involved in co-evolution process which may intimate significant functional/structural communications between them. Conclusions The strong competition between ferns and angiosperms for light may have been the main cause for a continuous fixation of adaptive amino acid changes in psbA , in particular after its duplication. Alternatively, a single psbA copy may have undergone bursts of adaptive changes at the molecular level to overcome angiosperms competition. The strong signature of positive Darwinian selection in a major part of D1 protein is testament to this. At the same time, species own two psbA copies hardly have positive selection signals among the D1 protein coding sequences. In this study, eleven co-evolving sites have been detected via different molecules, which may be more important than others. PMID:22899792

Using combined measurements for comparison of light induction of stomatal conductance, electron transport rate and CO2 fixation in woody and fern species adapted to different light regimes.

PubMed

Wong, Shau-Lian; Chen, Chung-Wei; Huang, Hsien-Wen; Weng, Jen-Hsien

2012-05-01

We aimed to understand the relation of photosynthetic rate (A) with g(s) and electron transport rate (ETR) in species of great taxonomic range and light adaptation capability during photosynthetic light induction. We studied three woody species (Alnus formosana, Ardisia crenata and Ardisia cornudentata) and four fern species (Pyrrosia lingus, Asplenium antiquum, Diplazium donianum and Archangiopteris somai) with different light adaptation capabilities. Pot-grown materials received 100 and/or 10% sunlight according to their light adaptation capabilities. At least 4 months after light acclimation, CO(2) and H(2)O exchange and chlorophyll fluorescence were measured simultaneously by equipment in the laboratory. In plants adapted or acclimated to low light, dark-adapted leaves exposed to 500 or 2000 µmol m(-2) s(-1) photosynthetic photon flux (PPF) for 30 min showed low gross photosynthetic rate (P(g)) and short time required to reach 90% of maximum P(g) (). At the initiation of illumination, two broad-leaved understory shrubs and the four ferns, especially ferns adapted to heavy shade, showed higher stomatal conductance (g(s)) than pioneer tree species; materials with higher g(s) had short at both 500 and 2000 µmol m(-2) s(-1) PPF. With 500 or 2000 µmol m(-2) s(-1) PPF, the g(s) for the three woody species increased from 2 to 30 min after the start of illumination, but little change in the g(s) of the four ferns. Thus, P(g) and g(s) were not correlated for all material measured at the same PPF and induction time. However, P(g) was positively correlated with ETR, even though CO(2) assimilation may be influenced by stomatal, biochemical and photoinhibitory limitations. In addition, was closely related to time required to reach 90% maximal ETR for all materials and with two levels of PPF combined. Thus, ETR is a good indicator for estimating the light induction of photosynthetic rate of species, across a wide taxonomic range and light adaptation and acclimation capability.

Effect of habitat preference on frond life span in three Cyathea tree ferns

NASA Astrophysics Data System (ADS)

Chiu, Tzu Yun; Wang, Hsiang Hua; Lun Kuo, Yao; Kume, Tomonori

2013-04-01

It has been reported that plants living in various geographical areas had different physiological forms, as factors of microenvironment have strong impacts on physiological characters. However, the physiological characters of fronds have been scarcely reported in ferns. In this study, we investigated physiological differences in response to the habitat preference in the three tree ferns in northeast Taiwan, Cyathea lepifera, C. spinulosa, and C. podophylla, prefer to open site, edge of forest, and interior forest, respectively. The canopy openness above the individuals of C. lepifera, C. spinulosa and C. podophylla were 29.2 ± 14.10 , 7.0 ± 3.07 and 5.0 ± 2.24 %, respectively. Among three species, C. podophylla had the longest frond life span (13.0 ± 4.12 months) than the two others (C. lepifera (6.8 ± 1.29 months) and C. spinulosa (7.3 ±1.35 months). Our result supported the general patterns that shade intolerant species have a shorter leaf life span than shade tolerant species. The maximum net CO2 assimilation of C. lepifera, C. spinulosa and C. podophylla were 11.46 ± 1.34, 8.27 ± 0.69, and 6.34 ± 0.54 μmol CO2 m-2 s-1, respectively. As well, C. lepifera had the highest photosynthetic light saturation point (LSP), while C. podophylla had the lowest LSP among these three tree ferns. These suggested that C. lepifera could be more efficient for capturing and utilizing light resources under the larger canopy openness condition than the other two species. We also found that frond C : N ratio were positively correlated with frond life span among species. C. podophylla, with the longest frond life span, had the highest frond C : N ratio (22.17 ± 1.95), which was followed by C. spinulosa (18.58 ± 1.37) and C. lepifera (18.68 ± 2.63) with shorter frond life span. The results were consistent to the theory that the fronds and leaves of shade intolerant species have high photosynthetic abilities with low C : N ratio. Key words: Canopy openness, frond life span, tree fern, Cyathea, frond C : N ratio

Physiological and ultrastructural characterisation of a desiccation-tolerant filmy fern, Hymenophyllum caudiculatum: Influence of translational regulation and ABA on recovery.

PubMed

Garcés, M; Ulloa, M; Miranda, A; Bravo, L A

2018-03-01

The filmy fern Hymenophyllum caudiculatum can lose 60% of its relative water content, remain dry for some time and recover 88% of photochemical efficiency after 30 min of rehydration. Little is known about the protective strategies and regulation of the cellular rehydration process in this filmy fern species. The aim of this study was to characterise the filmy fern ultrastructure during a desiccation-rehydration cycle, and measure the physiological effects of transcription/translation inhibitors and ABA during desiccation recovery. Confocal and transmission electron microscopy were used to compare changes in structure during fast or slow desiccation. Transcription (actinomycin D) and translation (cycloheximide) inhibitors and ABA were used to compare photochemical efficiency during desiccation recovery. Cell structure was conserved during slow desiccation and rehydration, constitutive properties of the cell wall, allowing invagination and folding of the membranes and an important change in chloroplast size. The use of a translational inhibitor impeded recovery of photochemical efficiency during the first 80 min of rehydration, but the transcriptional inhibitor had no effect. Exogenous ABA delayed photochemical inactivation, and endogenous ABA levels decreased during desiccation and rehydration. Frond curling and chloroplast movements are possible strategies to avoid photodamage. Constitutive membrane plasticity and rapid cellular repair can be adaptations evolved to tolerate a rapid recovery during rehydration. Further research is required to explore the importance of existing mRNAs during the first minutes of recovery, and ABA function during desiccation of H. caudiculatum. © 2017 German Society for Plant Sciences and The Royal Botanical Society of the Netherlands.

Consequences of extinction in tropical peat-forming vegetation of the Middle to Late Pennsylvanian (Westphalian-Stephanian)

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

DiMichele, W.A.; Phillips, T.L.

1992-01-01

Peat-forming environments (coals) were major landscape elements of the Pennsylvanian tropics. Mires reached a pantropical zenith during the 9 Ma of the Westphalian when long intervals of similar vegetation were separated by short intervals of rapid change. Differences between successive vegetation types primarily reflect different proportions of several major habitat-specific subfloras within which species turnover occurred. A hierarchy of organizational levels is suggested in which biotic interactions helped structure and constrain patterns of species replacement. Lycopsids were the framework trees of nearly all Westphalian mires; tree ferns and pteridosperm were important subdominants by the late Westphalian. Environmental changes, largely climatic,more » during the Westphalian-Stephanian transition resulted in extinction of most mire species, particularly trees. Tree ferns dominated Stephanian mires following a short transitional period of small-lycopsid and fern abundance. Tree ferns were cheaply constructed opportunists and their rise in abundance coincided with an increase in species numbers throughout tropical lowlands. Within mires there was an increase in physical size of plants from several major lineages. The structure and dynamics of Stephanian mires differed from the Westphalian; previously sharp distinctions between mires and other lowland floras diminished. The Westphalian to Stephanian vegetational changes suggest that ecosystems can display a brittle'' response to environmental change. Such threshold responses are a likely consequences of levels of extinction high enough to disrupt ecosystem fabric. The success of opportunistic lineages following loss of indigenous mire vegetation constitutes a secondary replacement, with establishment of a new equilibrium within hundreds of thousands of years.« less

Understanding mechanisms of rarity in pteridophytes: competition and climate change threaten the rare fern Asplenium scolopendrium var. americanum (Aspleniaceae).

PubMed

Testo, Weston L; Watkins, James E

2013-11-01

Understanding the ecology of rare species can inform aspects of conservation strategies; however, the mechanisms of rarity remain elusive for most pteridophytes, which possess independent and ecologically distinct gametophyte and sporophyte generations. To elucidate factors contributing to recent declines of the rare fern Asplenium scolopendrium var. americanum, we studied the ecology and ecophysiology of its gametophyte generation, focusing on responses to competition, temperature, and water stress. Gametophytes of A. scolopendrium var. americanum, its widespread European relative A. scolopendrium var. scolopendrium, and five co-occurring fern species were grown from spores. Gametophytes were grown at 20°C and 25°C, and germination rates, intra- and interspecific competition, desiccation tolerance, and sporophyte production were determined for all species. Gametophytes of A. scolopendrium var. americanum had the lowest rates of germination and sporophyte production among all species studied and exhibited the greatest sensitivity to interspecific competition, temperature increases, and desiccation. Mature gametophytes of A. scolopendrium var. americanum grown at 25°C were 84.6% smaller than those grown at 20°C, and only 1.5% produced sporophytes after 200 d in culture. Similar responses were not observed in other species studied. The recent declines and current status of populations of A. scolopendrium var. americanum are linked to its gametophyte's limited capacity to tolerate competition and physiological stress linked to climate change. This is the first study to develop a mechanistic understanding of rarity and decline in a fern and demonstrates the importance of considering the ecology of the gametophyte in plants with independent sporophyte and gametophyte generations.

Paleomycology of the Princeton Chert. III. Dictyosporic microfungi, Monodictysporites princetonensis gen. et sp. nov., associated with decayed rhizomes of an Eocene semi-aquatic fern.

PubMed

Klymiuk, Ashley A

2016-09-01

This study builds on previous investigations of paleomycological diversity within permineralized plants of a significant Eocene paleobotanical locality, the Princeton Chert. The fungal body fossils described here occur in decayed rhizomes of the extinct semi-aquatic fern Dennstaedtiopsis aerenchymata Fungi include vegetative hyphae throughout the plant tissue, as well as a dense assemblage of >100 dematiaceous spores. The spores occur in a discrete zone surrounding two extraneous rootlets of other plants, which penetrated the fern tissue post-mortem. Spores are obovoid and muriform, composed of 8-12 cells with constricted septa and produced from hyaline or slightly pigmented hyphae. The spores are morphologically similar to both asexual reproductive dictyospores of phylogenetically disparate microfungi attributed to the morphogenus Monodictys and perennating dictyochlamydospores that occur in the anamorph genus Phoma In addition to expanding the early Eocene fossil record for Ascomycota, these specimens also provide new insight into the rapidity of initial phases of the fossilization process in this important paleobotanical locality. © 2016 by The Mycological Society of America.

Development of suitable hydroponics system for phytoremediation of arsenic-contaminated water using an arsenic hyperaccumulator plant Pteris vittata.

PubMed

Huang, Yi; Miyauchi, Keisuke; Inoue, Chihiro; Endo, Ginro

2016-01-01

In this study, we found that high-performance hydroponics of arsenic hyperaccumulator fern Pteris vittata is possible without any mechanical aeration system, if rhizomes of the ferns are kept over the water surface level. It was also found that very low-nutrition condition is better for root elongation of P. vittata that is an important factor of the arsenic removal from contaminated water. By the non-aeration and low-nutrition hydroponics for four months, roots of P. vittata were elongated more than 500 mm. The results of arsenate phytofiltration experiments showed that arsenic concentrations in water declined from the initial concentrations (50 μg/L, 500 μg/L, and 1000 μg/L) to lower than the detection limit (0.1 μg/L) and about 80% of arsenic removed was accumulated in the fern fronds. The improved hydroponics method for P. vittata developed in this study enables low-cost phytoremediation of arsenic-contaminated water and high-affinity removal of arsenic from water.

Development of the gametophyte of the fern Schizaea pusilla

NASA Technical Reports Server (NTRS)

Kiss, J. Z.; Swatzell, L. J.

1996-01-01

Schizaea pusilla is a pteridophyte with several unique developmental characteristics. In contrast to most other fern species, S. pusilla gametophytes remain filamentous throughout their development, and the gametophytes are associated with an endophytic fungus which appears to be mycorrhizal. In terms of tropistic responses, apical filament cells of young gametophytes are negatively phototropic compared with germ filaments of other ferns which exhibit positive phototropism. Cryofixation (propane jet freezing and high-pressure freezing) in conjunction with freeze substitution electron microscopy was used to study young gametophytes. The results demonstrate that apical filament cells have a distinctive structural polarity and that rhizoids also can be successfully frozen by these methods. The cytoskeleton and endomembrane system were particularly well preserved in cryofixed cells. In addition, Schizaea gametophytes were used as a test system to evaluate potential artifacts of propane jet freezing and high pressure freezing. There was little apparent difference in ultrastructure between cells cryofixed by either freezing method. These gametophytes will be useful in determining the effectiveness of cryofixation techniques and as a model system in tip growth studies.

Leaf micromorphology of four medicinal ferns species in Tasik Chini, Pahang

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

Nurnida, M. K., E-mail: nurnidakamal@gmail.com; Noraini, T.; Ruzi, A. R.

A leaf micromorphology study was conducted on four selected medicinal ferns species in Tasik Chini, Pahang. The four chosen species were Adiantum latifolium Lam., Lygodium flexuosum (L.) Sw., Lygodium microphyllum (Cav.) R. Br. and Tectaria singaporeana (Wall.) Ching. The objective of this study is to identify the leaf micromorphological characteristics that can be used as supportive scientific data especially in authentification of medicinal ferns species. The procedures involved such as dehydration, critical point drying, gold coated and examination under scanning electron microscope. Results in this study have shown some similarities and variations in the leaf micromorphological characteristics such as presencemore » of cuticular striation, type of epicuticular waxes, structural feature of stomata and also in the presence or absence and type of trichomes. Four types of epicuticular waxes and only one type of trichome were observed, that were specific for some species. As a conclusion, the results of this study definitely proven that leaf micromorphology can be used for species authentification and might useful as preliminary scientific data for future references and further study.« less

Arbuscular mycorrhizal colonization in field-collected terrestrial cordate gametophytes of pre-polypod leptosporangiate ferns (Osmundaceae, Gleicheniaceae, Plagiogyriaceae, Cyatheaceae).

PubMed

Ogura-Tsujita, Yuki; Hirayama, Yumiko; Sakoda, Aki; Suzuki, Ayako; Ebihara, Atsushi; Morita, Nana; Imaichi, Ryoko

2016-02-01

To determine the mycorrhizal status of pteridophyte gametophytes in diverse taxa, the mycorrhizal colonization of wild gametophytes was investigated in terrestrial cordate gametophytes of pre-polypod leptosporangiate ferns, i.e., one species of Osmundaceae (Osmunda banksiifolia), two species of Gleicheniaceae (Diplopterygium glaucum, Dicranopteris linearis), and four species of Cyatheales including tree ferns (Plagiogyriaceae: Plagiogyria japonica, Plagiogyria euphlebia; Cyatheaceae: Cyathea podophylla, Cyathea lepifera). Microscopic observations revealed that 58 to 97% of gametophytes in all species were colonized with arbuscular mycorrhizal (AM) fungi. Fungal colonization was limited to the multilayered midrib (cushion) tissue in all gametophytes examined. Molecular identification using fungal SSU rDNA sequences indicated that the AM fungi in gametophytes primarily belonged to the Glomeraceae, but also included the Claroideoglomeraceae, Gigasporaceae, Acaulosporaceae, and Archaeosporales. This study provides the first evidence for AM fungal colonization of wild gametophytes in the Plagiogyriaceae and Cyatheaceae. Taxonomically divergent photosynthetic gametophytes are similarly colonized by AM fungi, suggesting that mycorrhizal associations with AM fungi could widely occur in terrestrial pteridophyte gametophytes.

De novo transcriptome assembly of a fern, Lygodium japonicum, and a web resource database, Ljtrans DB.

PubMed

Aya, Koichiro; Kobayashi, Masaaki; Tanaka, Junmu; Ohyanagi, Hajime; Suzuki, Takayuki; Yano, Kenji; Takano, Tomoyuki; Yano, Kentaro; Matsuoka, Makoto

2015-01-01

During plant evolution, ferns originally evolved as a major vascular plant with a distinctive life cycle in which the haploid and diploid generations are completely separated. However, the low level of genetic resources has limited studies of their physiological events, as well as hindering research on the evolutionary history of land plants. In this study, to identify a comprehensive catalog of transcripts and characterize their expression traits in the fern Lygodium japonicum, nine different RNA samples isolated from prothalli, trophophylls, rhizomes and sporophylls were sequenced using Roche 454 GS-FLX and Illumina HiSeq sequencers. The hybrid assembly of the high-quality 454 GS-FLX and Illumina HiSeq reads generated a set of 37,830 isoforms with an average length of 1,444 bp. Using four open reading frame (ORF) predictors, 38,142 representative ORFs were identified from a total of 37,830 transcript isoforms and 95 contigs, which were annotated by searching against several public databases. Furthermore, an orthoMCL analysis using the protein sequences of L. japonicum and five model plants revealed various sets of lineage-specific genes, including those detected among land plant lineages and those detected in only L. japonicum. We have also examined the expression patterns of all contigs/isoforms, along with the life cycle of L. japonicum, and identified the tissue-specific transcripts using statistical expression analyses. Finally, we developed a public web resource, the L. japonicum transcriptome database at http://bioinf.mind.meiji.ac.jp/kanikusa/, which provides important opportunities to accelerate molecular research in ferns. © The Author 2014. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Two-Step Functional Innovation of the Stem-Cell Factors WUS/WOX5 during Plant Evolution

PubMed Central

Zhang, Yuzhou; Jiao, Yue; Jiao, Hengwu

2017-01-01

WUS and WOX5, which are expressed, respectively, in the organizing center (OC) and the quiescent center (QC), are essential for shoot/root apical stem-cell maintenance in flowering plants. However, little is known about how these stem-cell factors evolved their functions in flowering plants. Here, we show that the WUS/WOX5 proteins acquired two distinct capabilities by a two-step functional innovation process in the course of plant evolution. The first-step is the apical stem-cell maintenance activity of WUS/WOX5, which originated in the common ancestor of ferns and seed plants, as evidenced by the interspecies complementation experiments, showing that ectopic expression of fern Ceratopteris richardii WUS-like (CrWUL) surrounding OC/QC, or exclusive OC-/QC-expressed gymnosperms/angiosperms WUS/WOX5 in Arabidopsis wus-1 and wox5-1 mutants, could rescue their phenotypes. The second-step is the intercellular mobility that emerged in the common ancestor of seed plants after divergence from the ferns. Evidence for this includes confocal imaging of GFP fusion proteins, showing that WUS/WOX5 from seed plants, rather than from the fern CrWUL, can migrate into cells adjacent to the OC/QC. Evolutionary analysis showed that the WUS-like gene was duplicated into two copies prior to the divergence of gymnosperms/angiosperms. Then the two gene copies (WUS and WOX5) have undergone similar levels of purifying selection, which is consistent with their conserved functions in angiosperm shoot/root stem-cell maintenance and floral organ formation. Our results highlight the critical roles and the essential prerequisites that the two-step functional innovation of these genes performs and represents in the origin of flowering plants. PMID:28053005

Changes in gametophyte physiology of Pteris multifida induced by the leaf leachate treatment of the invasive Bidens pilosa.

PubMed

Zhang, Kai-Mei; Shen, Yu; Fang, Yan-Ming; Liu, Ying

2016-02-01

In recent years, the response of fern gametophytes to environment has raised much attention. However, studies on the influence of plant invasion to fern gametophytes are scarce. Allelopathy plays an important role in biological invasion. Hence, it is necessary to study the allelopathic effects of invasive plants on fern gametophytes and elucidate the mechanisms by which invasive plants cause phytotoxicity. As one of the main invasive plants in China, Bidens pilosa exhibits allelopathic effects on spermatophyte growth. Field investigation shows that many ferns are threatened by the invasion of B. pilosa. The distribution of Pteris multifida overlaps with that of B. pilosa in China. To examine the potential involvement of allelopathic mechanisms of B. pilosa leaves, changes in the physiology in P. multifida gametophytes are analyzed. We found that cell membrane and antioxidant enzyme activities as well as photosynthesis pigment contents of the gametophytes were affected by B. pilosa leachates. Gametophytes of P. multifida exposed to B. pilosa had increased damages to cell membranes, expressed in thiobarbituric acid reacting substance (TBARS) concentrations, malondialdehyde (MDA), electrolyte leakage (membrane permeability), and degree of injury. Enzyme activities, assessed by superoxide dismutase (SOD) and catalase (CAT) as well as guaiacol peroxidase (GPX) enhanced with the increase in leachate concentration after 2-day exposure. Meanwhile, lower chlorophyll a (Chl a), chlorophyll b (Chl b), carotenoid (Car), and the total chlorophyll were measured as leachate concentrations increased. At day 10, leaf leachates of B. pilosa exhibited the greatest inhibition. These results suggest that the observed inhibitory or stimulatory effects on the physiology studied can have an adverse effect on P. multifida and that allelopathic interference seems to have involved in this process.

Natural radionuclides in lichens, mosses and ferns in a thermal power plant and in an adjacent coal mine area in southern Brazil.

PubMed

Galhardi, Juliana Aparecida; García-Tenorio, Rafael; Díaz Francés, Inmaculada; Bonotto, Daniel Marcos; Marcelli, Marcelo Pinto

2017-02-01

The radio-elements 234 U, 235 U, 238 U, 230 Th, 232 Th and 210 Po were characterized in lichens, mosses and ferns species sampled in an adjacent coal mine area at Figueira City, Paraná State, Brazil, due to their importance for the assessment of human exposure related to the natural radioactivity. The coal is geologically associated with a uranium deposit and has been used as a fossil fuel in a thermal power plant in the city. Samples were initially prepared at LABIDRO (Isotopes and Hydrochemistry Laboratory), UNESP, Rio Claro (SP), Brazil. Then, alpha-spectrometry after several radiochemical steps was used at the Applied Nuclear Physics Laboratories, University of Seville, Seville, Spain, for measuring the activity concentration of the radionuclides. It was 210 Po the radionuclide that most bio-accumulates in the organisms, reaching the highest levels in mosses. The ferns species were less sensitive as bio-monitor than the mosses and lichens, considering polonium in relation to other radionuclides. Fruticose lichens exhibited lower polonium content than the foliose lichens sampled in the same site. Besides biological features, environmental characteristics also modify the radio-elements absorption by lichens and mosses like the type of vegetation covering these organisms, their substrate, the prevailing wind direction, elevation and climatic conditions. Only 210 Po and 238 U correlated in ferns and in soil and rock materials, being particulate emissions from the coal-fired power plant the most probable U-source in the region. Thus, the biomonitors used were able to detect atmospheric contamination by the radionuclides monitored. Copyright © 2016 Elsevier Ltd. All rights reserved.

Population genetic variation in the tree fern Alsophila spinulosa (Cyatheaceae): effects of reproductive strategy.

PubMed

Wang, Ting; Su, Yingjuan; Li, Yuan

2012-01-01

Essentially all ferns can perform both sexual and asexual reproduction. Their populations represent suitable study objects to test the population genetic effects of different reproductive systems. Using the diploid homosporous fern Alsophila spinulosa as an example species, the main purpose of this study was to assess the relative impact of sexual and asexual reproduction on the level and structure of population genetic variation. Inter-simple sequence repeats analysis was conducted on 140 individuals collected from seven populations (HSG, LCH, BPC, MPG, GX, LD, and ZHG) in China. Seventy-four polymorphic bands discriminated a total of 127 multilocus genotypes. Character compatibility analysis revealed that 50.0 to 70.0% of the genotypes had to be deleted in order to obtain a tree-like structure in the data set from populations HSG, LCH, MPG, BPC, GX, and LD; and there was a gradual decrease of conflict in the data set when genotypes with the highest incompatibility counts were successively deleted. In contrast, in population ZHG, only 33.3% of genotypes had to be removed to achieve complete compatibility in the data set, which showed a sharp decline in incompatibility upon the deletion of those genotypes. All populations examined possessed similar levels of genetic variation. Population ZHG was not found to be more differentiated than the other populations. Sexual recombination is the predominant source of genetic variation in most of the examined populations of A. spinulosa. However, somatic mutation contributes most to the genetic variation in population ZHG. This change of the primary mode of reproduction does not cause a significant difference in the population genetic composition. Character compatibility analysis represents an effective approach to separate the role of sexual and asexual components in shaping the genetic pattern of fern populations.

Local differentiation of cell wall matrix polysaccharides in sinuous pavement cells: its possible involvement in the flexibility of cell shape.

PubMed

Sotiriou, P; Giannoutsou, E; Panteris, E; Galatis, B; Apostolakos, P

2018-03-01

The distribution of homogalacturonans (HGAs) displaying different degrees of esterification as well as of callose was examined in cell walls of mature pavement cells in two angiosperm and two fern species. We investigated whether local cell wall matrix differentiation may enable pavement cells to respond to mechanical tension forces by transiently altering their shape. HGA epitopes, identified with 2F4, JIM5 and JIM7 antibodies, and callose were immunolocalised in hand-made or semithin leaf sections. Callose was also stained with aniline blue. The structure of pavement cells was studied with light and transmission electron microscopy (TEM). In all species examined, pavement cells displayed wavy anticlinal cell walls, but the waviness pattern differed between angiosperms and ferns. The angiosperm pavement cells were tightly interconnected throughout their whole depth, while in ferns they were interconnected only close to the external periclinal cell wall and intercellular spaces were developed between them close to the mesophyll. Although the HGA epitopes examined were located along the whole cell wall surface, the 2F4- and JIM5- epitopes were especially localised at cell lobe tips. In fern pavement cells, the contact sites were impregnated with callose and JIM5-HGA epitopes. When tension forces were applied on leaf regions, the pavement cells elongated along the stretching axis, due to a decrease in waviness of anticlinal cell walls. After removal of tension forces, the original cell shape was resumed. The presented data support that HGA epitopes make the anticlinal pavement cell walls flexible, in order to reversibly alter their shape. Furthermore, callose seems to offer stability to cell contacts between pavement cells, as already suggested in photosynthetic mesophyll cells. © 2017 German Society for Plant Sciences and The Royal Botanical Society of the Netherlands.

Remarkable, overlooked and new microfungi in North Rhine-Westphalia, Germany.

PubMed

Ale-Agha, N; Feige, G B; Linke, K

2001-01-01

During our investigations of the micro flora in NRW in the years of 1999 and 2000 we were able to collect and identify some new and rare species of micro fungi as parasites and saprophytes on wild and ornamental plants. Some of them are new for Germany: Podosphaera xanthii on Coreopsis verticillata; Cercospora traversiana on Trigonella foenum-graecum; Passalora dubia on Atriplex hortensis; Ophiobolus cirsii on Carduus spec.; Periconia britannica on Polemonium coeruleum; Ascochyta leptospora on Agropyron repens; Apomelasmia urticae on Urtica dioica; Cryptodiaporthe salicina on Salix caprea; Dasyscyphus nidulus on Anemone hupehensis; Rhopographus filicinus on Pteridium aquilinum; Sillia ferruginea on Corylus avellana; Sirococcus spiraeae on Spiraea spec. and Forsythia x intermedia. Examples of these findings are in the Herbarium ESS (Mycotheca Parva, Slg. Feige/Ale-Agha).

Arsenic uptake by common marsh fern Thelypteris palustris and its potential for phytoremediation.

PubMed

Anderson, LaShunda; Walsh, Maud M

2007-07-01

Hydroponic and soil cultivations of Thelypteris palustris, the common marsh fern, were used to investigate its potential for use in phytoremediation of arsenic (As) contaminated water or soil. ICP-MS analyses indicate that both roots and fronds accumulated arsenic in levels up to 100 times the concentration of treatment solutions of 250 microg/L and 500 mug/L arsenic, but values varied widely and there was no significant difference in concentrations in fronds between the control (no arsenic) and treatments. Plants exposed to 500 microg/L exhibited necrosis in their fronds, suggesting that Thelypteris palustris is not a good candidate for phyotoremediation of arsenic-contaminated sites.

Water-clover ferns, Marsilea, in the Southeastern United States

USGS Publications Warehouse

Jacono, Colette C.; Johnson, David M.

2006-01-01

A surge in the collection of exotic Marsilea, M. mutica, M. minuta and M. hirsuta in the southeastern United States has prompted the need for updated identification aids. This study provides an annotated key to all water-clover ferns occurring in the region. It describes and illustrates recently documented exotic species and a previously misidentified western introduction. It details the rediscovery of M. ancylopoda, presumed extinct, and confirms its identification as the western species M. oligospora. Finally it clarifies the status and distribution of two additional western North American species introduced to the southeast, M. vestita and M. macropoda.

Architectural mutation and leaf form, for the palmate series.

PubMed

White, D A

2005-07-21

Palmate leaf form occurs in both the ferns and angiosperms. The palmate leaf form, and its variants, is present in distantly separated clades within both ferns and angiosperms. There tend not to be intermediate forms which link these palmate leaves to other leaf forms within the taxonomic groups in question. The recurrence of homoplasious leaf forms in separate taxonomic groups could be a consequence of the algorithmic like mode of leaf growth. Leaves develop through the reiteration of modular units. It is probable that the homoplasious leaf forms in different taxa are derived independently through re-combinations of the parameters in the basic leaf form development algorithm.

Abscisic acid (ABA) and key proteins in its perception and signaling pathways are ancient, but their roles have changed through time.

PubMed

Sussmilch, Frances C; Atallah, Nadia M; Brodribb, Timothy J; Banks, Jo Ann; McAdam, Scott A M

2017-09-02

Homologs of the Arabidopsis core abscisic acid (ABA) signaling component OPEN STOMATA1 (OST1) are best known for their role in closing stomata in angiosperm species. We recently characterized a fern OST1 homolog, GAMETOPHYTES ABA INSENSITIVE ON ANTHERDIOGEN 1 (GAIA1), which is not required for stomatal closure in ferns, consistent with physiologic evidence that shows the stomata of these plants respond passively to changes in leaf water status. Instead, gaia1 mutants reveal a critical role in ABA signaling for spore dormancy and sex determination, in a system regulated by antagonism between ABA and the gibberellin (GA)-derived fern hormone antheridiogen (A CE ). ABA and key proteins, including ABA receptors from the PYR/PYL/RCAR family and negative regulators of ABA-signaling from Group A of the type-2C protein phosphatases (PP2Cs), in addition to OST1 homologs, can be found in all terrestrial land plant lineages, ranging from liverworts that lack stomata, to angiosperms. As land plants have evolved and diversified over the past 450 million years, so too have the roles of this important plant hormone and the genes involved in its signaling and perception.

[Effects of topography on the diversity and distribution pattern of ground plants in karst montane forests in Southwest Guangxi, China].

PubMed

Yuan, Tie-Xiang; Zhang, He-Ping; Ou, Zhi-Yang; Tan, Yi-Bo

2014-10-01

Covariance analysis, curve-fitting, and canonical correspondence analysis (CCA) were used to explore the effects of topographic factors on the plant diversity and distribution patterns of ground flora with different growth forms in the karst mountains of Southwest Guangxi, China. A total of 152 ground plants were recorded. Among them, 37 species were ferns, 44 species herbs, 9 species lianas, and 62 species shrubs. Covariance analysis revealed that altitude significantly correlated with the individual number and richness of ground plants, and slope aspect had a significant effect on richness. Statistical analyses showed a highly significant nonlinear correlation between the individual number or richness of ground plants and altitude. Results of CCA revealed that slope aspect had a significant effect on the distribution pattern of ferns, and slope had a significant effect on the distribution patterns of herbs, lianas and shrubs. Ferns were more sensitive than herbs, lianas and shrubs to changes in heat and soil water caused by aspect. The effect of slope was stronger than that of elevation on soil water and nutrients, and it was the most important topographic factor that affected the distribution patterns of herbs, lianas and shrubs in this region.

Nanoscale biomimetics studies of Salvinia molesta for micropattern fabrication.

PubMed

Hunt, James; Bhushan, Bharat

2011-11-01

The emerging field of biomimetics allows one to take inspiration from nature and mimic it in order to create various products, devices and structures. There are a large number of objects, including bacteria, plants, land and aquatic animals and seashells, with properties of commercial interest. The subject of interest for this research is the water fern Salvinia molesta because of its ability to trap air. Air-retaining surfaces are of technological interest due to their ability to reduce drag when used for fluid transport, ship coatings and other submersible industrial products in which drag is a concern. The purpose of this research is to mimic the air trapping ability of S. molesta in order to prove that a structure can be created in the lab that can mimic the behavior of the fern as well as demonstrate microfabrication techniques that can be utilized in industry to produce such materials. In this work, a novel methodology for the fabrication of microstructures that mimic the water-pinning and air-trapping ability of S. molesta is introduced. Water contact angle, water roll angle and adhesive force of the new microstructure and water fern are investigated. Copyright © 2011 Elsevier Inc. All rights reserved.

A review of the use of pteridophytes for treating human ailments*

PubMed Central

Baskaran, Xavier-ravi; Geo Vigila, Antony-varuvel; Zhang, Shou-zhou; Feng, Shi-xiu; Liao, Wen-bo

2018-01-01

The aim of this review was to explore the pharmacological activity of early tracheophytes (pteridophytes) as an alternative medicine for treating human ailments. As the first vascular plants, pteridophytes (aka, ferns and fern allies) are an ancient lineage, and human beings have been exploring and using taxa from this lineage for over 2000 years because of their beneficial properties. We have documented the medicinal uses of pteridophytes belonging to thirty different families. The lycophyte Selaginella sp. was shown in earlier studies to have multiple pharmacological activity, such as antioxidant, anti-inflammatory, anti-cancer, antidiabetic, antiviral, antimicrobial, and anti-Alzheimer properties. Among all the pteridophytes examined, taxa from the Pteridaceae, Polypodiaceae, and Adiantaceae exhibited significant medicinal activity. Based on our review, many pteridophytes have properties that could be used in alternative medicine for treatment of various human illnesses. Biotechnological tools can be used to preserve and even improve their bioactive molecules for the preparation of medicines against illness. Even though several studies have reported medicinal uses of ferns, the possible bioactive compounds of several pteridophytes have not been identified. Furthermore, their optimal dosage level and treatment strategies still need to be determined. Finally, the future direction of pteridophyte research is discussed. PMID:29405039

Fern-like rGO/BiVO4 Hybrid Nanostructures for High-Energy Symmetric Supercapacitor.

PubMed

Patil, Santosh S; Dubal, Deepak P; Deonikar, Virendrakumar G; Tamboli, Mohaseen S; Ambekar, Jalindar D; Gomez-Romero, Pedro; Kolekar, Sanjay S; Kale, Bharat B; Patil, Deepak R

2016-11-23

Herein, we demonstrate the synthesis of rGO/BiVO 4 hybrid nanostructures by facile hydrothermal method. Morphological studies reveal that rGO sheets are embedded in the special dendritic fern-like structures of BiVO 4 . The rGO/BiVO 4 hybrid architecture shows the way to a rational design of supercapacitor, since these structures enable easy access of electrolyte ions by reducing internal resistance. Considering the unique morphological features of rGO/BiVO 4 hybrid nanostructures, their supercapacitive properties were investigated. The rGO/BiVO 4 electrode exhibits a specific capacitance of 151 F/g at the current density of 0.15 mA/cm 2 . Furthermore, we have constructed rGO/BiVO 4 symmetric cell which exhibits outstanding volumetric energy density of 1.6 mW h/cm 3 (33.7 W h/kg) and ensures rapid energy delivery with power density of 391 mW/cm 3 (8.0 kW/kg). The superior properties of symmetric supercapacitor can be attributed to the special dendritic fern-like BiVO 4 morphology and intriguing physicochemical properties of rGO.

Leaf hydraulic capacity in ferns, conifers and angiosperms: impacts on photosynthetic maxima.

PubMed

Brodribb, Tim J; Holbrook, N Michele; Zwieniecki, Maciej A; Palma, Beatriz

2005-03-01

* The hydraulic plumbing of vascular plant leaves varies considerably between major plant groups both in the spatial organization of veins, as well as their anatomical structure. * Five conifers, three ferns and 12 angiosperm trees were selected from tropical and temperate forests to investigate whether the profound differences in foliar morphology of these groups lead to correspondingly profound differences in leaf hydraulic efficiency. * We found that angiosperm leaves spanned a range of leaf hydraulic conductance from 3.9 to 36 mmol m2 s-1 MPa-1, whereas ferns (5.9-11.4 mmol m-2 s-1 MPa-1) and conifers (1.6-9.0 mmol m-2 s-1 MPa-1) were uniformly less conductive to liquid water. Leaf hydraulic conductance (Kleaf) correlated strongly with stomatal conductance indicating an internal leaf-level regulation of liquid and vapour conductances. Photosynthetic capacity also increased with Kleaf, however, it became saturated at values of Kleaf over 20 mmol m-2 s-1 MPa-1. * The data suggest that vessels in the leaves of the angiosperms studied provide them with the flexibility to produce highly conductive leaves with correspondingly high photosynthetic capacities relative to tracheid-bearing species.

Influence of gravity and light on the developmental polarity of Ceratopteris richardii fern spores

NASA Technical Reports Server (NTRS)

Edwards, E. S.; Roux, S. J.

1998-01-01

The polarity of germinating single-celled spores of the fern Ceratopteris richardii Brogn. is influenced by gravity during a time period prior to the first cellular division designated a "polarity-determination window". After this window closes, control of polarity is seen in the downward (with respect to gravity) migration of the nucleus along the proximal face of the spore and the subsequent downward growth of the primary rhizoid. When spores are germinated on a clinostat the direction of nuclear migration and subsequent primary rhizoid growth is random. However, in each case the direction of nuclear migration predicts the direction of rhizoid elongation. Although it is the most obvious movement, the downward migration is not the first movement of the nucleus. During the polarity-determination window, the nucleus moves randomly within a region centered behind the trilete marking. While the polarity of many fern spores has been reported to be controlled by light, spores of C. richardii are the first documented to have their polarity influenced by gravity. Directional white light also affects the polarity of these spores, but this influence is slight and is secondary to that of gravity.

Lianas, tree ferns and understory species: indicators of conservation status in the Brazilian Atlantic Rainforest remnants, southeastern Brazil.

PubMed

Castello, A C D; Coelho, S; Cardoso-Leite, E

2017-01-01

Indicators are applied faster and at lower costs than conventional surveys, providing quick and efficient responses that can facilitate protected areas management. Our aim was to select indicators from vegetation to monitor protected areas. For this purpose, we analyzed understory and quantified lianas and tree ferns in protected and non-protected areas, in order to find indicator species. Our study areas are located in Vale do Ribeira, southeastern São Paulo state, Brazil. One of the areas is under two protection categories (IUCN's categories II and V), and the other is a privately owned farm. Lianas with large diameters (> 13 cm) and tree ferns with great heights (> 19 m) were considered indicators of undisturbed areas (protected areas) because their growth is directly related to forest successional stage. Indicator species within the protected area were shade tolerant species, such as Bathysa australis (A.St.-Hil.) K.Schum., whereas outside the protected area were pioneer species, such as Pera glabrata (Schott) Poepp. ex Baill. e Nectandra oppositifolia Ness. All of the suggested indicators can be used in management actions, especially in protected areas, to guarantee forest maintenance and ensure fulfillment of the conservation objectives of these areas.

Evolution of green plants as deduced from 5S rRNA sequences.

PubMed

Hori, H; Lim, B L; Osawa, S

1985-02-01

We have constructed a phylogenic tree for green plants by comparing 5S rRNA sequences. The tree suggests that the emergence of most of the uni- and multicellular green algae such as Chlamydomonas, Spirogyra, Ulva, and Chlorella occurred in the early stage of green plant evolution. The branching point of Nitella is a little earlier than that of land plants and much later than that of the above green algae, supporting the view that Nitella-like green algae may be the direct precursor to land plants. The Bryophyta and the Pteridophyta separated from each other after emergence of the Spermatophyta. The result is consistent with the view that the Bryophyta evolved from ferns by degeneration. In the Pteridophyta, Psilotum (whisk fern) separated first, and a little later Lycopodium (club moss) separated from the ancestor common to Equisetum (horsetail) and Dryopteris (fern). This order is in accordance with the classical view. During the Spermatophyta evolution, the gymnosperms (Cycas, Ginkgo, and Metasequoia have been studied here) and the angiosperms (flowering plants) separated, and this was followed by the separation of Metasequoia and Cycas (cycad)/Ginkgo (maidenhair tree) on one branch and various flowering plants on the other.

Evolution of green plants as deduced from 5S rRNA sequences

PubMed Central

Hori, Hiroshi; Lim, Byung-Lak; Osawa, Syozo

1985-01-01

We have constructed a phylogenic tree for green plants by comparing 5S rRNA sequences. The tree suggests that the emergence of most of the uni- and multicellular green algae such as Chlamydomonas, Spirogyra, Ulva, and Chlorella occurred in the early stage of green plant evolution. The branching point of Nitella is a little earlier than that of land plants and much later than that of the above green algae, supporting the view that Nitella-like green algae may be the direct precursor to land plants. The Bryophyta and the Pteridophyta separated from each other after emergence of the Spermatophyta. The result is consistent with the view that the Bryophyta evolved from ferns by degeneration. In the Pteridophyta, Psilotum (whisk fern) separated first, and a little later Lycopodium (club moss) separated from the ancestor common to Equisetum (horsetail) and Dryopteris (fern). This order is in accordance with the classical view. During the Spermatophyta evolution, the gymnosperms (Cycas, Ginkgo, and Metasequoia have been studied here) and the angiosperms (flowering plants) separated, and this was followed by the separation of Metasequoia and Cycas (cycad)/Ginkgo (maidenhair tree) on one branch and various flowering plants on the other. PMID:16593540

Stomatal dynamics are limited by leaf hydraulics in ferns and conifers: results from simultaneous measurements of liquid and vapour fluxes in leaves.

PubMed

Martins, Samuel C V; McAdam, Scott A M; Deans, Ross M; DaMatta, Fábio M; Brodribb, Tim J

2016-03-01

Stomatal responsiveness to vapour pressure deficit (VPD) results in continuous regulation of daytime gas-exchange directly influencing leaf water status and carbon gain. Current models can reasonably predict steady-state stomatal conductance (gs ) to changes in VPD but the gs dynamics between steady-states are poorly known. Here, we used a diverse sample of conifers and ferns to show that leaf hydraulic architecture, in particular leaf capacitance, has a major role in determining the gs response time to perturbations in VPD. By using simultaneous measurements of liquid and vapour fluxes into and out of leaves, the in situ fluctuations in leaf water balance were calculated and appeared to be closely tracked by changes in gs thus supporting a passive model of stomatal control. Indeed, good agreement was found between observed and predicted gs when using a hydropassive model based on hydraulic traits. We contend that a simple passive hydraulic control of stomata in response to changes in leaf water status provides for efficient stomatal responses to VPD in ferns and conifers, leading to closure rates as fast or faster than those seen in most angiosperms. © 2015 John Wiley & Sons Ltd.

Evaluation of atpB nucleotide sequences for phylogenetic studies of ferns and other pteridophytes.

PubMed

Wolf, P

1997-10-01

Inferring basal relationships among vascular plants poses a major challenge to plant systematists. The divergence events that describe these relationships occurred long ago and considerable homoplasy has since accrued for both molecular and morphological characters. A potential solution is to examine phylogenetic analyses from multiple data sets. Here I present a new source of phylogenetic data for ferns and other pteridophytes. I sequenced the chloroplast gene atpB from 23 pteridophyte taxa and used maximum parsimony to infer relationships. A 588-bp region of the gene appeared to contain a statistically significant amount of phylogenetic signal and the resulting trees were largely congruent with similar analyses of nucleotide sequences from rbcL. However, a combined analysis of atpB plus rbcL produced a better resolved tree than did either data set alone. In the shortest trees, leptosporangiate ferns formed a monophyletic group. Also, I detected a well-supported clade of Psilotaceae (Psilotum and Tmesipteris) plus Ophioglossaceae (Ophioglossum and Botrychium). The demonstrated utility of atpB suggests that sequences from this gene should play a role in phylogenetic analyses that incorporate data from chloroplast genes, nuclear genes, morphology, and fossil data.

Robust face alignment under occlusion via regional predictive power estimation.

PubMed

Heng Yang; Xuming He; Xuhui Jia; Patras, Ioannis

2015-08-01

Face alignment has been well studied in recent years, however, when a face alignment model is applied on facial images with heavy partial occlusion, the performance deteriorates significantly. In this paper, instead of training an occlusion-aware model with visibility annotation, we address this issue via a model adaptation scheme that uses the result of a local regression forest (RF) voting method. In the proposed scheme, the consistency of the votes of the local RF in each of several oversegmented regions is used to determine the reliability of predicting the location of the facial landmarks. The latter is what we call regional predictive power (RPP). Subsequently, we adapt a holistic voting method (cascaded pose regression based on random ferns) by putting weights on the votes of each fern according to the RPP of the regions used in the fern tests. The proposed method shows superior performance over existing face alignment models in the most challenging data sets (COFW and 300-W). Moreover, it can also estimate with high accuracy (72.4% overlap ratio) which image areas belong to the face or nonface objects, on the heavily occluded images of the COFW data set, without explicit occlusion modeling.

Palynology, petrography and geochemistry of the Sewickley coal bed (Monongahela Group, Late Pennsylvanian), Northern Appalachian Basin, USA

USGS Publications Warehouse

Eble, C.F.; Pierce, B.S.; Grady, W.C.

2003-01-01

Forty-two bench samples of the Sewickley coal bed were collected from seven localities in the northern Appalachian Basin and analyzed palynologically, petrographically, and geochemically. The Sewickley coal bed occurs in the middle of the Pittsburgh Formation (Monongahela Group) and is of Late Pennsylvanian age. Palynologically, it is dominated by spores of tree ferns. Tree fern spore taxa in the Sewickley include Punctatisporites minutus, Punctatosporites minutus, Laevigatosporites minimus, Spinosporites exiguus, Apiculatasporites saetiger, and Thymospora spp. In fact, Punctatisporites minutus was so abundant that it had to be removed from the standard counts and recorded separately (average 73.2%). Even when Punctatisporites minutus is removed from the counts, tree fern spores still dominate a majority of the assemblages, averaging 64.4%. Among the tree fern spores identified in the Sewickley coal, Thymospora exhibits temporal and spatial abundance variation. Thymospora usually increases in abundance from the base to the top of the bed. Thymospora is also more abundant in columns that are thick (>100 cm) and low in ash yield (< 12.0%, dry basis). Calamite spores (e.g. Calamospora spp., Laevigatosporites minor, and L. vulgaris) are the next most abundant plant group represented in the Sewickley coal, averaging 20%. Contributions from all other plant groups are minor in comparison. Petrographically, the Sewickley coal contains high percentages of vitrinite (average 82.3%, mineral matter-free (mmf)), with structured forms being more common than unstructured forms. In contrast, liptinite and inertinite macerals both occur in low percentages (average 7.7% and 10.0%, respectively). Geochemically, the Sewickley coal has a moderate ash yield (average 12.4%) and high total sulfur content (average 3.4%). Four localities contained a high ash or carbonaceous shale bench. These benches, which may be coeval, are strongly dominated by tree fern spores. Unlike the lower ash benches, they contain low percentages of vitrinite, which mainly occurs as unstructured vitrinite, and higher liptinite and inertinite contents. The accumulated data suggest that the Sewickley paleomire was probably a rheotrophic, planar mire that had a consistent water cover. This is supported by the high vitrinite contents, moderate ash yields, and high total sulfur contents. The high ash and carbonaceous shale benches probably represent either periods of dryness and substrate exposure, or flooding of the mire surface, the duration of which is unknown. ?? 2003 Elsevier B.V. All rights reserved.

Description of the female of the Peruvian sand fly Lutzomyia reclusa (Diptera: Psychodidae: Phlebotominae).

PubMed

Ibáñez-Bernal, Sergio; Cáceres, Abraham G

2011-03-01

The female of the phlebotomine sand fly Lutzomyia reclusa Fernández & Rogers 1991 [= Pintomyia (Pifanomyia) reclusa (Fernández & Rogers) sensu Galati], is described for the first time, based on specimens collected in the Department of Cajamarca, in northern Peru. The female can be recognized from other species of the series pia, species group Verrucarum, by wing venation with beta shorter than half of alpha, labrum just shorter than head width but longer than flagellomere 1, palpomere 5 much longer than palpomere 3, arrangement of cibarial armature, and form of spermathecae and relative size of spermathecal ducts. Diagnostic characters and measurements of the male of Lu. reclusa are provided as well.

Crowdfunding the Azolla fern genome project: a grassroots approach.

PubMed

Li, Fay-Wei; Pryer, Kathleen M

2014-01-01

Much of science progresses within the tight boundaries of what is often seen as a "black box". Though familiar to funding agencies, researchers and the academic journals they publish in, it is an entity that outsiders rarely get to peek into. Crowdfunding is a novel means that allows the public to participate in, as well as to support and witness advancements in science. Here we describe our recent crowdfunding efforts to sequence the Azolla genome, a little fern with massive green potential. Crowdfunding is a worthy platform not only for obtaining seed money for exploratory research, but also for engaging directly with the general public as a rewarding form of outreach.

Crowdfunding the Azolla fern genome project: a grassroots approach

PubMed Central

2014-01-01

Much of science progresses within the tight boundaries of what is often seen as a “black box”. Though familiar to funding agencies, researchers and the academic journals they publish in, it is an entity that outsiders rarely get to peek into. Crowdfunding is a novel means that allows the public to participate in, as well as to support and witness advancements in science. Here we describe our recent crowdfunding efforts to sequence the Azolla genome, a little fern with massive green potential. Crowdfunding is a worthy platform not only for obtaining seed money for exploratory research, but also for engaging directly with the general public as a rewarding form of outreach. PMID:25276348

Effect of synthetic detergents on germination of fern spores

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

Devi, Y.; Devi, S.

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 onmore » pteridophytes and the development of spore germination assay for phytoxicity evaluation.« less

Second-order kinetic model for the sorption of cadmium onto tree fern: a comparison of linear and non-linear methods.

PubMed

Ho, Yuh-Shan

2006-01-01

A comparison was made of the linear least-squares method and a trial-and-error non-linear method of the widely used pseudo-second-order kinetic model for the sorption of cadmium onto ground-up tree fern. Four pseudo-second-order kinetic linear equations are discussed. Kinetic parameters obtained from the four kinetic linear equations using the linear method differed but they were the same when using the non-linear method. A type 1 pseudo-second-order linear kinetic model has the highest coefficient of determination. Results show that the non-linear method may be a better way to obtain the desired parameters.

Phytoremediation of arsenic-contaminated groundwater using arsenic hyperaccumulator Pteris vittata L.: effects of frond harvesting regimes and arsenic levels in refill water.

PubMed

Natarajan, Seenivasan; Stamps, Robert H; Ma, Lena Q; Saha, Uttam K; Hernandez, Damaris; Cai, Yong; Zillioux, Edward J

2011-01-30

A large-scale hydroponic system to phytoremediate arsenic-contaminated groundwater using Pteris vittata (Chinese brake fern) was successfully tested in a field. In this 30-wk study, three frond-harvesting regimes (all, mature, and senescing fronds) and two water-refilling schemes to compensate for evapotranspiration (high-As water of 140-180 μg/L and low-As water of <7 μg/L) were investigated. Two experiments (Cycle 1 and Cycle 2) were conducted using the same plants in 24 tanks with each containing 600 L of arsenic-contaminated groundwater and 32 ferns. During Cycle 1 and with initial As of 140 μg/L, As in tanks refilled with low-As water was reduced to <10 μg/L in 8 wks compared to <10 μg/L in 17 wks in tanks refilled with high-As water. During Cycle 2 and with initial As of 180 μg/L, the remediation time was reduced by 2-5 wks, indicating that more established ferns were more efficient. In areas where clean water is limiting, refilling high-As water coupled with harvesting senescing fronds is recommended for more effective As phytoremediation. Published by Elsevier B.V.

Dr. Roberto Miguel Klein Herbarium (FURB), Blumenau, Southern Brazil

PubMed Central

de Gasper, André Luís; Vibrans, Alexander Christian; Funez, Luís Adriano; Rigon-Jr, Morilo José; Bittencourt, Felipe; Vieira, Carina

2014-01-01

Abstract The premise of this study is to present the collection of the FURB herbarium, its collection area and type specimens, as well as its projects and contributions to the flora of the Subtropical Atlantic Forest. The FURB herbarium currently has nearly 41,000 records of vascular plants and has the largest collection of lycophytes and ferns in Southern Brazil, with more than 8,000 records. More than 4,500 scanned images of 4,436 species are available online, and it is expected that the whole collection will be scanned in less than one year. There are 198 families of angiosperms, 33 of ferns, three of lycophytes and six of gymnosperms. All collections of the Floristic and Forest Inventory of Santa Catarina project are recorded in FURB, which represents almost 35,000 herbarium specimens. The families with the largest number of species are: Cyperaceae (109 species), Rubiaceae (129), Solanaceae (131), Poaceae (155), Melastomataceae (157), Myrtaceae (257), Orchidaceae (288), Fabaceae (323), and Asteraceae (426), between angiosperms. Among the ferns and lycophytes are: Hymenophyllaceae (30), Thelypteridaceae (31), Aspleniaceae (32), Dryopteridaceae (43), Pteridaceae (54) and Polypodiaceae (60). There are five type specimens among them: one holotype, one isotype and three paratypes. To date, the FURB herbarium has donated 19,521 herbarium duplicates for identification or expansion of other herbaria. PMID:25383009

Changes in photosynthetic rate and stress volatile emissions through desiccation-rehydration cycles in desiccation-tolerant epiphytic filmy ferns (Hymenophyllaceae).

PubMed

Niinemets, Ülo; Bravo, León A; Copolovici, Lucian

2018-07-01

Exposure to recurrent desiccation cycles carries a risk of accumulation of reactive oxygen species that can impair leaf physiological activity upon rehydration, but changes in filmy fern stress status through desiccation and rewatering cycles have been poorly studied. We studied foliage photosynthetic rate and volatile marker compounds characterizing cell wall modifications (methanol) and stress development (lipoxygenase [LOX] pathway volatiles and methanol) through desiccation-rewatering cycles in lower-canopy species Hymenoglossum cruentum and Hymenophyllum caudiculatum, lower- to upper-canopy species Hymenophyllum plicatum and upper-canopy species Hymenophyllum dentatum sampled from a common environment and hypothesized that lower canopy species respond more strongly to desiccation and rewatering. In all species, rates of photosynthesis and LOX volatile emission decreased with progression of desiccation, but LOX emission decreased with a slower rate than photosynthesis. Rewatering first led to an emission burst of LOX volatiles followed by methanol, indicating that the oxidative burst was elicited in the symplast and further propagated to cell walls. Changes in LOX emissions were more pronounced in the upper-canopy species that had a greater photosynthetic activity and likely a greater rate of production of photooxidants. We conclude that rewatering induces the most severe stress in filmy ferns, especially in the upper canopy species. © 2018 John Wiley & Sons Ltd.

Integrated resource scheduling in a distributed scheduling environment

NASA Technical Reports Server (NTRS)

Zoch, David; Hall, Gardiner

1988-01-01

The Space Station era presents a highly-complex multi-mission planning and scheduling environment exercised over a highly distributed system. In order to automate the scheduling process, customers require a mechanism for communicating their scheduling requirements to NASA. A request language that a remotely-located customer can use to specify his scheduling requirements to a NASA scheduler, thus automating the customer-scheduler interface, is described. This notation, Flexible Envelope-Request Notation (FERN), allows the user to completely specify his scheduling requirements such as resource usage, temporal constraints, and scheduling preferences and options. The FERN also contains mechanisms for representing schedule and resource availability information, which are used in the inter-scheduler inconsistency resolution process. Additionally, a scheduler is described that can accept these requests, process them, generate schedules, and return schedule and resource availability information to the requester. The Request-Oriented Scheduling Engine (ROSE) was designed to function either as an independent scheduler or as a scheduling element in a network of schedulers. When used in a network of schedulers, each ROSE communicates schedule and resource usage information to other schedulers via the FERN notation, enabling inconsistencies to be resolved between schedulers. Individual ROSE schedules are created by viewing the problem as a constraint satisfaction problem with a heuristically guided search strategy.

Late Cretaceous Aquatic Plant World in Patagonia, Argentina

PubMed Central

Cúneo, N. Rubén; Gandolfo, María A.; Zamaloa, María C.; Hermsen, Elizabeth

2014-01-01

In this contribution, we describe latest Cretaceous aquatic plant communities from the La Colonia Formation, Patagonia, Argentina, based on their taxonomic components and paleoecological attributes. The La Colonia Formation is a geological unit deposited during a Maastrichtian-Danian transgressive episode of the South Atlantic Ocean. This event resulted in the deposition of a series of fine-grained sediments associated with lagoon systems occurring along irregular coastal plains in northern Patagonia. These deposits preserved a diverse biota, including aquatic and terrestrial plants and animals. The aquatic macrophytes can be broadly divided into two groups: free-floating and rooted, the latter with emergent or floating leaves. Free-floating macrophytes include ferns in Salviniaceae (Azolla and Paleoazolla) and a monocot (Araceae). Floating microphytes include green algae (Botryoccocus, Pediastrum and Zygnemataceae). Among the rooted components, marsileaceous water ferns (including Regnellidium and an extinct form) and the eudicot angiosperm Nelumbo (Nelumbonaceae) are the dominant groups. Terrestrial plants occurring in the vegetation surrounding the lagoons include monocots (palms and Typhaceae), ferns with affinities to Dicksoniaceae, conifers, and dicots. A reconstruction of the aquatic plant paleocommuniy is provided based on the distribution of the fossils along a freshwater horizon within the La Colonia Formation. This contribution constitutes the first reconstruction of a Cretaceous aquatic habitat for southern South America. PMID:25148081

Phytoremediation of Hg and Cd from industrial effluents using an aquatic free floating macrophyte Azolla pinnata.

PubMed

Rai, Prabhat Kumar

2008-01-01

The level of heavy metal pollution in Singrauli, an industrial region in India, was assessed and the phytoremediation capacity of a small water fern, Azolla pinnata R.BR (Azollaceae), was observed to purify waters polluted by two heavy metals, i.e., mercury (Hg) and cadmium (Cd) under a microcosm condition. Azolla pinnata is endemic to India and is an abundant and easy-growing free-floating water fern usually found in the rice fields, polluted ponds, and reservoirs of India. The fern was grown in 24 40-L aquariums containing Hg2+ and Cd2+ ions each in concentrations of 0.5, 1.0, and 3.0 mgL(-1) during the course of this study. The study revealed an inhibition of Azolla pinnata growth by 27.0-33.9% with the highest in the presence of Hg (II) ions at 0.5 mgL(-1) in comparison to the control After 13 days of the experiment, metal contents in the solution were decreased up to 70-94%. In the tissues of Azolla pinnata, the concentration of selected heavy metals during investigation was recorded between 310 and 740 mgKg(-1) dry mass, with the highest levelfoundfor Cd (II) treatment at 3.0 mgL(-1) containing a metal solution.

Phylogeny and systematics of the brake fern genus Pteris (Pteridaceae) based on molecular (plastid and nuclear) and morphological evidence.

PubMed

Zhang, Liang; Zhang, Li-Bing

2018-01-01

The brake fern genus Pteris belongs to Pteridaceae subfamily Pteridoideae. It is one of the largest fern genera and has been estimated to contain 200-250 species distributed on all continents except Antarctica. Previous studies were either based on plastid data only or based on both plastid and nuclear data but the sampling was small. In addition, an infrageneric classification of Pteris based on morphological and molecular evidence has not been available yet. In the present study, based on molecular data of eight plastid markers and one nuclear marker (gapCp) of 256 accessions representing ca. 178 species of Pteris, we reconstruct a global phylogeny of Pteris. The 15 major clades identified earlier are recovered here and we further identified a new major clade. Our nuclear phylogeny recovered 11 of these 16 major clades, seven of which are strongly supported. The inclusion of Schizostege in Pteris is confirmed for the first time. Based on the newly reconstructed phylogeny and evidence from morphology, distribution and/or ecology, we classify Pteris into three subgenera: P. subg. Pteris, P. subg. Campteria, and P. subg. Platyzoma. The former two are further divided into three and 12 sections, respectively. Copyright © 2017 Elsevier Inc. All rights reserved.

Impact of the Intensive Program of Emotional Intelligence (IPEI) on work supervisors.

PubMed

Rodríguez García, Gustavo A; López-Pérez, Belén; Férreo Cruzado, Manuel A; Fernández Carrascoso, María E; Fernández, Juan

2017-11-01

This study aimed to evaluate the effect of the Intensive Program of Emotional Intelligence (IPEI; Fernández, 2016; Férreo, 2016) on middle managers’ emotional intelligence, as this variable may have a significant impact on personal satisfaction, task performance, and the work environment. The intervention was applied to work team supervisors in a large call center, as it is an overlooked sector in this topic. Two-hundred and eighty-two supervisors from a Madrid-based, Spanish multinational (51.4% men and 48.6% women) participated in this study. Participants were assigned to the experimental group (n = 190) or the control group (n = 92) by availability, according to management decision. All supervisors filled in two questionnaires to evaluate the different components of intrapersonal emotional intelligence (i.e., attention, clarity, and repair; TMMS-24; Fernández-Berrocal, Extremera, & Ramos, 2004) and cognitive and affective empathy (i.e., perspective taking, emotion understanding, empathic joy, and personal distress; TECA; López-Pérez, Fernández, & Abad, 2008). The findings showed an increase in the studied variables for the experimental group. The results obtained support middle managers’ training in emotional competences through short, efficient, economic programs. Potential limitations and implications of the results are discussed.

Abrupt deceleration of molecular evolution linked to the origin of arborescence in ferns.

PubMed

Korall, Petra; Schuettpelz, Eric; Pryer, Kathleen M

2010-09-01

Molecular rate heterogeneity, whereby rates of molecular evolution vary among groups of organisms, is a well-documented phenomenon. Nonetheless, its causes are poorly understood. For animals, generation time is frequently cited because longer-lived species tend to have slower rates of molecular evolution than their shorter-lived counterparts. Although a similar pattern has been uncovered in flowering plants, using proxies such as growth form, the underlying process has remained elusive. Here, we find a deceleration of molecular evolutionary rate to be coupled with the origin of arborescence in ferns. Phylogenetic branch lengths within the “tree fern” clade are considerably shorter than those of closely related lineages, and our analyses demonstrate that this is due to a significant difference in molecular evolutionary rate. Reconstructions reveal that an abrupt rate deceleration coincided with the evolution of the long-lived tree-like habit at the base of the tree fern clade. This suggests that a generation time effect may well be ubiquitous across the green tree of life, and that the search for a responsible mechanism must focus on characteristics shared by all vascular plants. Discriminating among the possibilities will require contributions from various biological disciplines,but will be necessary for a full appreciation of molecular evolution.

Origin of the endemic fern genus Diellia coincides with the renewal of Hawaiian terrestrial life in the Miocene

PubMed Central

Schneider, Harald; Ranker, Tom A.; Russell, Stephen J.; Cranfill, Raymond; Geiger, Jennifer M.O.; Aguraiuja, Ruth; Wood, Ken R.; Grundmann, Michael; Kloberdanz, Keelie; Vogel, Johannes C.

2005-01-01

The enigmatic fern genus Diellia, endemic to the Hawaiian archipelago, consists of five extant and one recently extinct species. Diellia is morphologically highly variable, and a unique combination of characters has led to several contrasting hypotheses regarding the relationship of Diellia to other ferns. A phylogenetic analysis of four chloroplast loci places Diellia within ‘black-stemmed’ rock spleenworts of the species-rich genus Asplenium, as previously suggested by W. H. Wagner. Using an external calibration point, we estimate the divergence of the Diellia lineage from its nearest relatives to have occurred at ca. 24.3 Myr ago matching an independent estimate for the renewal of Hawaiian terrestrial life (ca. 23 Myr ago). We therefore suggest that the ancestor of the Diellia lineage may have been among the first successful colonists of the newly emerging islands in the archipelago. Disparity between morphological and nucleotide sequence variation within Diellia is consistent with a recent rapid radiation. Our estimated time of the Diellia radiation (ca. 2 Myr ago) is younger than the oldest island of Kaua’i (ca. 5.1 Myr ago) but older than the younger major islands of Maui (ca. 1.3 Myr ago), Lana’i (ca. 1.3 Myr ago) and Hawaii (ca. 0.43 Myr ago). PMID:15734701

The fossil Osmundales (Royal Ferns)—a phylogenetic network analysis, revised taxonomy, and evolutionary classification of anatomically preserved trunks and rhizomes

PubMed Central

2017-01-01

The Osmundales (Royal Fern order) originated in the late Paleozoic and is the most ancient surviving lineage of leptosporangiate ferns. In contrast to its low diversity today (less than 20 species in six genera), it has the richest fossil record of any extant group of ferns. The structurally preserved trunks and rhizomes alone are referable to more than 100 fossil species that are classified in up to 20 genera, four subfamilies, and two families. This diverse fossil record constitutes an exceptional source of information on the evolutionary history of the group from the Permian to the present. However, inconsistent terminology, varying formats of description, and the general lack of a uniform taxonomic concept renders this wealth of information poorly accessible. To this end, we provide a comprehensive review of the diversity of structural features of osmundalean axes under a standardized, descriptive terminology. A novel morphological character matrix with 45 anatomical characters scored for 15 extant species and for 114 fossil operational units (species or specimens) is analysed using networks in order to establish systematic relationships among fossil and extant Osmundales rooted in axis anatomy. The results lead us to propose an evolutionary classification for fossil Osmundales and a revised, standardized taxonomy for all taxa down to the rank of (sub)genus. We introduce several nomenclatural novelties: (1) a new subfamily Itopsidemoideae (Guaireaceae) is established to contain Itopsidema, Donwelliacaulis, and Tiania; (2) the thamnopteroid genera Zalesskya, Iegosigopteris, and Petcheropteris are all considered synonymous with Thamnopteris; (3) 12 species of Millerocaulis and Ashicaulis are assigned to modern genera (tribe Osmundeae); (4) the hitherto enigmatic Aurealcaulis is identified as an extinct subgenus of Plenasium; and (5) the poorly known Osmundites tuhajkulensis is assigned to Millerocaulis. In addition, we consider Millerocaulis stipabonettiorum a possible member of Palaeosmunda and Millerocaulis estipularis as probably constituting the earliest representative of the (Todea-)Leptopteris lineage (subtribe Todeinae) of modern Osmundoideae. PMID:28713650

Potential of mosquito fern (Azolla caroliniana Willd.) plants as a biofilter for cadmium removal from waste water

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

Sajwam, K.S.; Ornes, W.H.

1995-12-31

The aquatic vascular Mosquito Fern (Azolla Caroliania Willd.) was investigated as a potential biological filter for removal of Cd from waste water. Mosquito Fern plants were grown in and harvested weekly from 0.10 M Hoagland nutrient solutions containing 0.01, 0.04, and 1.03 {mu}g Cd mL{sup -1} or 0.50 M Hoagland nutrient solutions containing 0.02, 1.0, and 9.14,{mu}g Cd mL{sup -1}. Dry weights of plants significantly increased when exposed to all three Cd concentrations in 0. 10 M Hoagland solution through week three then decreased thereafter. However, in plants exposed to Cd treatments in 0.50 M Hoagland solution, dry weights increasedmore » through week one and decreased thereafter. Tissue Cd concentrations in plants grown in 0.10 M Hoagland solution increased during the first two weeks followed by decreases in week 3 and 4. However, tissue Cd increased through week 3 in plants grown in 0.50 M Hoagland solutions. Cadmium exposure to plants grown in 0.10 M Hoagland solution seemed to increase the tissue P concentrations in plants exposed to the lowest concentration of Cd. Tissue P in both control and treated plants in 0.50 M Hoagland solution seemed to increase over time with exception of the medium level (1 {mu}g Cd mL{sup -1}). These results suggest that Mosquito Fern would be useful for absorbing Cd from nutrient-rich water when the solution concentration was in the range of as low as 0.01 and as high as 9.14 {mu}g Cd mL{sup -1}. However, the harvest regime would have to be every one or two weeks to sustain plant vigor and realize maximum uptake of Cd from solution.« less

A comparison of the dietary arsenic exposures from ingestion of contaminated soil and hyperaccumulating Pteris ferns used in a residential phytoremediation project.

PubMed

Ebbs, Stephen; Hatfield, Sarah; Nagarajan, Vinay; Blaylock, Michael

2010-01-01

Arsenic (As) hyperaccumulating ferns are used to phytoremediate As-contaminated soils, including soils in residential areas. This use may pose a health risk if children were to ingest these plants. Spider brake (Pteris cretica L.) plants were grown in sand spiked with arsenate, to produce tissue As concentrations (2000-4500 mg kg DW(-1)) typical of those observed in plants deployed for As phytoremediation. The fronds were subjected to a physiologically-based extraction test to estimate As bioaccessibility, which ranged from 3.4-20.5%. A scenario for human dietary exposure to As in an urban setting was then estimated for a child consuming 0.25 g DW of tissue. The calculation of dietary exposure took into account the As concentration in the fern pinnae, the bioaccessibility of As in the tissue, and the typical absorption of inorganic As by the gastrointestinal tract. The pinnae As concentrations and the calculated dietary exposures were used to create a non-linear regression model relating tissue As concentration to dietary exposure. Data from a phytoremediation project in a residential area using Pteris cretica and Pteris vittata (L.) were input into this model to project dietary As exposure in a residential phytoremediation setting. These exposures were compared to estimates of dietary As exposure from the consumption of soil. The results showed that dietary exposures to As from consumption of soil or pinnae tissue were similar and that estimates of dietary exposure were below the LOAEL value of 14 microg As kg(-1) d(-1). The results suggest that the hyperaccumulation of As in Pteris ferns during growth in moderately contaminated residential soils (e.g., < or = 100 mg As kg DW(-1)) does not represent an inherent risk or a risk substantially different from that posed by accidental ingestion of contaminated soil.

The fossil Osmundales (Royal Ferns)-a phylogenetic network analysis, revised taxonomy, and evolutionary classification of anatomically preserved trunks and rhizomes.

PubMed

Bomfleur, Benjamin; Grimm, Guido W; McLoughlin, Stephen

2017-01-01

The Osmundales (Royal Fern order) originated in the late Paleozoic and is the most ancient surviving lineage of leptosporangiate ferns. In contrast to its low diversity today (less than 20 species in six genera), it has the richest fossil record of any extant group of ferns. The structurally preserved trunks and rhizomes alone are referable to more than 100 fossil species that are classified in up to 20 genera, four subfamilies, and two families. This diverse fossil record constitutes an exceptional source of information on the evolutionary history of the group from the Permian to the present. However, inconsistent terminology, varying formats of description, and the general lack of a uniform taxonomic concept renders this wealth of information poorly accessible. To this end, we provide a comprehensive review of the diversity of structural features of osmundalean axes under a standardized, descriptive terminology. A novel morphological character matrix with 45 anatomical characters scored for 15 extant species and for 114 fossil operational units (species or specimens) is analysed using networks in order to establish systematic relationships among fossil and extant Osmundales rooted in axis anatomy. The results lead us to propose an evolutionary classification for fossil Osmundales and a revised, standardized taxonomy for all taxa down to the rank of (sub)genus. We introduce several nomenclatural novelties: (1) a new subfamily Itopsidemoideae (Guaireaceae) is established to contain Itopsidema , Donwelliacaulis , and Tiania ; (2) the thamnopteroid genera Zalesskya , Iegosigopteris , and Petcheropteris are all considered synonymous with Thamnopteris ; (3) 12 species of Millerocaulis and Ashicaulis are assigned to modern genera (tribe Osmundeae); (4) the hitherto enigmatic Aurealcaulis is identified as an extinct subgenus of Plenasium ; and (5) the poorly known Osmundites tuhajkulensis is assigned to Millerocaulis . In addition, we consider Millerocaulis stipabonettiorum a possible member of Palaeosmunda and Millerocaulis estipularis as probably constituting the earliest representative of the ( Todea -) Leptopteris lineage (subtribe Todeinae) of modern Osmundoideae.

Two-Step Functional Innovation of the Stem-Cell Factors WUS/WOX5 during Plant Evolution.

PubMed

Zhang, Yuzhou; Jiao, Yue; Jiao, Hengwu; Zhao, Huabin; Zhu, Yu-Xian

2017-03-01

WUS and WOX5, which are expressed, respectively, in the organizing center (OC) and the quiescent center (QC), are essential for shoot/root apical stem-cell maintenance in flowering plants. However, little is known about how these stem-cell factors evolved their functions in flowering plants. Here, we show that the WUS/WOX5 proteins acquired two distinct capabilities by a two-step functional innovation process in the course of plant evolution. The first-step is the apical stem-cell maintenance activity of WUS/WOX5, which originated in the common ancestor of ferns and seed plants, as evidenced by the interspecies complementation experiments, showing that ectopic expression of fern Ceratopteris richardii WUS-like (CrWUL) surrounding OC/QC, or exclusive OC-/QC-expressed gymnosperms/angiosperms WUS/WOX5 in Arabidopsis wus-1 and wox5-1 mutants, could rescue their phenotypes. The second-step is the intercellular mobility that emerged in the common ancestor of seed plants after divergence from the ferns. Evidence for this includes confocal imaging of GFP fusion proteins, showing that WUS/WOX5 from seed plants, rather than from the fern CrWUL, can migrate into cells adjacent to the OC/QC. Evolutionary analysis showed that the WUS-like gene was duplicated into two copies prior to the divergence of gymnosperms/angiosperms. Then the two gene copies (WUS and WOX5) have undergone similar levels of purifying selection, which is consistent with their conserved functions in angiosperm shoot/root stem-cell maintenance and floral organ formation. Our results highlight the critical roles and the essential prerequisites that the two-step functional innovation of these genes performs and represents in the origin of flowering plants. © The Author 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Branched Features on the Floor of Antoniadni Crater

NASA Image and Video Library

2009-05-06

In this image from the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter, the dark branched features in the floor of Antoniadi Crater look like giant ferns, or fern casts. However, these ferns would be several miles in size and are composed of rough rocky materials. A more likely hypothesis is that this represents a channel network that now stands in inverted relief. The channels may have been lined or filled by indurated materials, making the channel fill more resistant to erosion by the wind than surrounding materials. After probably billions of years of wind erosion the resistant channels are now relatively high-standing. The material between the branched ridges has a fracture pattern and color similar to deposits elsewhere on Mars that are known to be rich in hydrated minerals such as clays. The inverted channels have short, stubby branches characteristic of formation by groundwater sapping. Spring water seeps into the channels and undercuts overlying layers, which collapse, so the channels grow headward. These images tell the story of an ancient wet environment on Mars, where life could have been possible. Ancient Martian life, if it existed, would most likely consist of microorganisms rather than giant tree ferns. This image, covering an area about 1 kilometer (0.6 mile) across, is a portion of the HiRISE observation catalogued as ESP_012435_2015, taken on March 22, 2009. The observation is centered at 21.4 degrees north latitude, 61.3 degrees east longitude. The image was taken at a local Mars time of 3:31 p.m. and the scene is illuminated from the west with a solar incidence angle of 66 degrees, thus the sun was about 24 degrees above the horizon. At a solar longitude of 232.1 degrees, the season on Mars is northern autumn. http://photojournal.jpl.nasa.gov/catalog/PIA12003

Identification of up-regulated genes from the metal-hyperaccumulator aquatic fern Salvinia minima Baker, in response to lead exposure.

PubMed

Leal-Alvarado, Daniel A; Martínez-Hernández, A; Calderón-Vázquez, C L; Uh-Ramos, D; Fuentes, G; Ramírez-Prado, J H; Sáenz-Carbonell, L; Santamaría, J M

2017-12-01

Lead (Pb) is one of the most serious environmental pollutants. The aquatic fern Salvinia minima Baker is capable to hyper-accumulate Pb in their tissues. However, the molecular mechanisms involved in its Pb accumulation and tolerance capacity are not fully understood. In order to investigate the molecular mechanisms that are activated by S. minima in response to Pb, we constructed a suppression subtractive hybridization library (SSH) in response to an exposure to 40μM of Pb(NO 3 ) 2 for 12h. 365 lead-related differentially expressed sequences tags (ESTs) were isolated and sequenced. Among these ESTs, 143 unique cDNA (97 were registered at the GenBank and 46 ESTs were not registered, because they did not meet the GenBank conditions). Those ESTs were identified and classified into 3 groups according to Blast2GO. In terms of metabolic pathways, they were grouped into 29 KEGG pathways. Among the ESTs, we identified some that might be part of the mechanism that this fern may have to deal with this metal, including abiotic-stress-related transcription factors, some that might be involved in tolerance mechanisms such as ROS scavenging, membrane protection, and those of cell homeostasis recovery. To validate the SSH library, 4 genes were randomly selected from the library and analyzed by qRT-PCR. These 4 genes were transcriptionally up-regulated in response to lead in at least one of the two tested tissues (roots and leaves). The present library is one of the few genomics approaches to study the response to metal stress in an aquatic fern, representing novel molecular information and tools to understand the molecular physiology of its Pb tolerance and hyperaccumulation capacity. Further research is required to elucidate the functions of the lead-induced genes that remain classified as unknown, to perhaps reveal novel molecular mechanisms of Pb tolerance and accumulation capacity in aquatic plants. Copyright © 2017 Elsevier B.V. All rights reserved.

Diverse spore rains and limited local exchange shape fern genetic diversity in a recently created habitat colonized by long-distance dispersal

PubMed Central

De Groot, G. A.; During, H. J.; Ansell, S. W.; Schneider, H.; Bremer, P.; Wubs, E. R. J.; Maas, J. W.; Korpelainen, H.; Erkens, R. H. J.

2012-01-01

Background and Aims Populations established by long-distance colonization are expected to show low levels of genetic variation per population, but strong genetic differentiation among populations. Whether isolated populations indeed show this genetic signature of isolation depends on the amount and diversity of diaspores arriving by long-distance dispersal, and time since colonization. For ferns, however, reliable estimates of long-distance dispersal rates remain largely unknown, and previous studies on fern population genetics often sampled older or non-isolated populations. Young populations in recent, disjunct habitats form a useful study system to improve our understanding of the genetic impact of long-distance dispersal. Methods Microsatellite markers were used to analyse the amount and distribution of genetic diversity in young populations of four widespread calcicole ferns (Asplenium scolopendrium, diploid; Asplenium trichomanes subsp. quadrivalens, tetraploid; Polystichum setiferum, diploid; and Polystichum aculeatum, tetraploid), which are rare in The Netherlands but established multiple populations in a forest (the Kuinderbos) on recently reclaimed Dutch polder land following long-distance dispersal. Reference samples from populations throughout Europe were used to assess how much of the existing variation was already present in the Kuinderbos. Key Results A large part of the Dutch and European genetic diversity in all four species was already found in the Kuinderbos. This diversity was strongly partitioned among populations. Most populations showed low genetic variation and high inbreeding coefficients, and were assigned to single, unique gene pools in cluster analyses. Evidence for interpopulational gene flow was low, except for the most abundant species. Conclusions The results show that all four species, diploids as well as polyploids, were capable of frequent long-distance colonization via single-spore establishment. This indicates that even isolated habitats receive dense and diverse spore rains, including genotypes capable of self-fertilization. Limited gene flow may conserve the genetic signature of multiple long-distance colonization events for several decades. PMID:22323427

Marine Biodiversity in Juan Fernández and Desventuradas Islands, Chile: Global Endemism Hotspots

PubMed Central

Friedlander, Alan M.; Ballesteros, Enric; Caselle, Jennifer E.; Gaymer, Carlos F.; Palma, Alvaro T.; Petit, Ignacio; Varas, Eduardo; Muñoz Wilson, Alex; Sala, Enric

2016-01-01

The Juan Fernández and Desventuradas islands are among the few oceanic islands belonging to Chile. They possess a unique mix of tropical, subtropical, and temperate marine species, and although close to continental South America, elements of the biota have greater affinities with the central and south Pacific owing to the Humboldt Current, which creates a strong biogeographic barrier between these islands and the continent. The Juan Fernández Archipelago has ~700 people, with the major industry being the fishery for the endemic lobster, Jasus frontalis. The Desventuradas Islands are uninhabited except for a small Chilean military garrison on San Félix Island. We compared the marine biodiversity of these islands across multiple taxonomic groups. At San Ambrosio Island (SA), in Desventuradas, the laminarian kelp (Eisenia cokeri), which is limited to Desventuradas in Chile, accounted for >50% of the benthic cover at wave exposed areas, while more sheltered sites were dominated by sea urchin barrens. The benthos at Robinson Crusoe Island (RC), in the Juan Fernández Archipelago, comprised a diverse mix of macroalgae and invertebrates, a number of which are endemic to the region. The biomass of commercially targeted fishes was >2 times higher in remote sites around RC compared to sheltered locations closest to port, and overall biomass was 35% higher around SA compared to RC, likely reflecting fishing effects around RC. The number of endemic fish species was extremely high at both islands, with 87.5% of the species surveyed at RC and 72% at SA consisting of regional endemics. Remarkably, endemics accounted for 99% of the numerical abundance of fishes surveyed at RC and 96% at SA, which is the highest assemblage-level endemism known for any individual marine ecosystem on earth. Our results highlight the uniqueness and global significance of these biodiversity hotspots exposed to very different fishing pressures. PMID:26734732

Marine Biodiversity in Juan Fernández and Desventuradas Islands, Chile: Global Endemism Hotspots.

PubMed

Friedlander, Alan M; Ballesteros, Enric; Caselle, Jennifer E; Gaymer, Carlos F; Palma, Alvaro T; Petit, Ignacio; Varas, Eduardo; Muñoz Wilson, Alex; Sala, Enric

2016-01-01

The Juan Fernández and Desventuradas islands are among the few oceanic islands belonging to Chile. They possess a unique mix of tropical, subtropical, and temperate marine species, and although close to continental South America, elements of the biota have greater affinities with the central and south Pacific owing to the Humboldt Current, which creates a strong biogeographic barrier between these islands and the continent. The Juan Fernández Archipelago has ~700 people, with the major industry being the fishery for the endemic lobster, Jasus frontalis. The Desventuradas Islands are uninhabited except for a small Chilean military garrison on San Félix Island. We compared the marine biodiversity of these islands across multiple taxonomic groups. At San Ambrosio Island (SA), in Desventuradas, the laminarian kelp (Eisenia cokeri), which is limited to Desventuradas in Chile, accounted for >50% of the benthic cover at wave exposed areas, while more sheltered sites were dominated by sea urchin barrens. The benthos at Robinson Crusoe Island (RC), in the Juan Fernández Archipelago, comprised a diverse mix of macroalgae and invertebrates, a number of which are endemic to the region. The biomass of commercially targeted fishes was >2 times higher in remote sites around RC compared to sheltered locations closest to port, and overall biomass was 35% higher around SA compared to RC, likely reflecting fishing effects around RC. The number of endemic fish species was extremely high at both islands, with 87.5% of the species surveyed at RC and 72% at SA consisting of regional endemics. Remarkably, endemics accounted for 99% of the numerical abundance of fishes surveyed at RC and 96% at SA, which is the highest assemblage-level endemism known for any individual marine ecosystem on earth. Our results highlight the uniqueness and global significance of these biodiversity hotspots exposed to very different fishing pressures.

Global biogeography of scaly tree ferns (Cyatheaceae): evidence for Gondwanan vicariance and limited transoceanic dispersal

PubMed Central

Korall, Petra; Pryer, Kathleen M

2014-01-01

Aim Scaly tree ferns, Cyatheaceae, are a well-supported group of mostly tree-forming ferns found throughout the tropics, the subtropics and the south-temperate zone. Fossil evidence shows that the lineage originated in the Late Jurassic period. We reconstructed large-scale historical biogeographical patterns of Cyatheaceae and tested the hypothesis that some of the observed distribution patterns are in fact compatible, in time and space, with a vicariance scenario related to the break-up of Gondwana. Location Tropics, subtropics and south-temperate areas of the world. Methods The historical biogeography of Cyatheaceae was analysed in a maximum likelihood framework using Lagrange. The 78 ingroup taxa are representative of the geographical distribution of the entire family. The phylogenies that served as a basis for the analyses were obtained by Bayesian inference analyses of mainly previously published DNA sequence data using MrBayes. Lineage divergence dates were estimated in a Bayesian Markov chain Monte Carlo framework using beast. Results Cyatheaceae originated in the Late Jurassic in either South America or Australasia. Following a range expansion, the ancestral distribution of the marginate-scaled clade included both these areas, whereas Sphaeropteris is reconstructed as having its origin only in Australasia. Within the marginate-scaled clade, reconstructions of early divergences are hampered by the unresolved relationships among the Alsophila, Cyathea and Gymnosphaera lineages. Nevertheless, it is clear that the occurrence of the Cyathea and Sphaeropteris lineages in South America may be related to vicariance, whereas transoceanic dispersal needs to be inferred for the range shifts seen in Alsophila and Gymnosphaera. Main conclusions The evolutionary history of Cyatheaceae involves both Gondwanan vicariance scenarios as well as long-distance dispersal events. The number of transoceanic dispersals reconstructed for the family is rather few when compared with other fern lineages. We suggest that a causal relationship between reproductive mode (outcrossing) and dispersal limitations is the most plausible explanation for the pattern observed. PMID:25435648

Global biogeography of scaly tree ferns (Cyatheaceae): evidence for Gondwanan vicariance and limited transoceanic dispersal.

PubMed

Korall, Petra; Pryer, Kathleen M

2014-02-01

Scaly tree ferns, Cyatheaceae, are a well-supported group of mostly tree-forming ferns found throughout the tropics, the subtropics and the south-temperate zone. Fossil evidence shows that the lineage originated in the Late Jurassic period. We reconstructed large-scale historical biogeographical patterns of Cyatheaceae and tested the hypothesis that some of the observed distribution patterns are in fact compatible, in time and space, with a vicariance scenario related to the break-up of Gondwana. Tropics, subtropics and south-temperate areas of the world. The historical biogeography of Cyatheaceae was analysed in a maximum likelihood framework using Lagrange. The 78 ingroup taxa are representative of the geographical distribution of the entire family. The phylogenies that served as a basis for the analyses were obtained by Bayesian inference analyses of mainly previously published DNA sequence data using MrBayes. Lineage divergence dates were estimated in a Bayesian Markov chain Monte Carlo framework using beast. Cyatheaceae originated in the Late Jurassic in either South America or Australasia. Following a range expansion, the ancestral distribution of the marginate-scaled clade included both these areas, whereas Sphaeropteris is reconstructed as having its origin only in Australasia. Within the marginate-scaled clade, reconstructions of early divergences are hampered by the unresolved relationships among the Alsophila , Cyathea and Gymnosphaera lineages. Nevertheless, it is clear that the occurrence of the Cyathea and Sphaeropteris lineages in South America may be related to vicariance, whereas transoceanic dispersal needs to be inferred for the range shifts seen in Alsophila and Gymnosphaera . The evolutionary history of Cyatheaceae involves both Gondwanan vicariance scenarios as well as long-distance dispersal events. The number of transoceanic dispersals reconstructed for the family is rather few when compared with other fern lineages. We suggest that a causal relationship between reproductive mode (outcrossing) and dispersal limitations is the most plausible explanation for the pattern observed.

Deglaciation and post-glacial environmental evolution in the Western Massif of Picos de Europa

NASA Astrophysics Data System (ADS)

Ruiz-Fernández, Jesús; Oliva, Marc; García, Cristina; López-Sáez, José Antonio; Gallinar, David; Geraldes, Miguel

2014-05-01

This study examines the process of deglaciation of the Western Massif of Picos de Europa through field work, geomorphological mapping, sedimentary records and absolute datings of 14C. This massif has several peaks over 2,400 m a.s.l. (Peña Santa de Castilla, 2,596 m; Torre Santa María, 2,486 m; Torre del Mediu, 2,467 m). It is composed mainly by Carboniferous limestones. This area has been intensively affected by karstic dissolution, Quaternary glaciers and fluvio-torrential processes (Miotke, 1968; Moreno et al, 2010; Ruiz-Fernández et al, 2009; Ruiz-Fernández, 2013). At present day, periglacial processes are active at the highest elevations (Ruiz-Fernández, 2013). We have identified four main glacial stages regarding the deglaciation of the massif: (i) maximum advance corresponding to the Last Glaciation, (ii) retreat and stabilization after the maximum advance, (iii) Late Glacial, and (iv) Little Ice Age. Sedimentological studies also contribute data to the understanding of the chronological framework of these environmental changes. The datings of the bottom sediments in two long sequences (8 and 5.4 m) provided a minimum age of 18,075 ± 425 cal BP for the maximum advance stage and 11,150 ± 900 cal BP for retreat and stabilization in the phase following the maximum advance. The ongoing analyses of these sequences at very high resolution will provide new knowledge about the environmental conditions prevailing since the deglaciation of the massif. References Miotke, F.D. (1968). Karstmorphologische studien in der glazial-überformten Höhenstufe der Picos de Europa, Nordspanien. Hannover, Selbtverlag der Geografischen Gessellschaft, 161 pp. Moreno, A., Valero, B.L., Jiménez, M., Domínguez, M.J., Mata, M.P., Navas, A., González, P., Stoll, H., Farias, P., Morellón, M., Corella, J.P. & Rico, M. (2010). The last deglaciation in the Picos de Europa National Park (Cantabrian Mountains, Northern Spain). Journal of Quaternary Science, 25 (7), 1076-1091. Ruiz-Fernández, J. (2013). Las formas de modelado glaciar, periglaciar y fluviotorrencial del Macizo Occidental de los Picos de Europa (Cordillera Cantábrica). Unpublished PhD Thesis, University of Oviedo, 314 pp. Ruiz-Fernández, J., Poblete. M.A., Serrano, P., Martí, C. & García-Ruiz, J.M. (2009). Morphometry of glacial cirques in the Cantabrian Range (Northwest Spain). Zeitschrift für Geomorphologie N. F., 53, 47-68.

The new philosophy of psychiatry: its (recent) past, present and future: a review of the Oxford University Press series International Perspectives in Philosophy and Psychiatry

PubMed Central

Banner, Natalie F; Thornton, Tim

2007-01-01

There has been a recent growth in philosophy of psychiatry that draws heavily (although not exclusively) on analytic philosophy with the aim of a better understanding of psychiatry through an analysis of some of its fundamental concepts. This 'new philosophy of psychiatry' is an addition to both analytic philosophy and to the broader interpretation of mental health care. Nevertheless, it is already a flourishing philosophical field. One indication of this is the new Oxford University Press series International Perspectives in Philosophy and Psychiatry seven volumes of which (by Bolton and Hill; Bracken and Thomas; Fulford, Morris, Sadler, and Stanghellini; Hughes, Louw, and Sabat; Pickering; Sadler; and Stanghellini) are examined in this critical review.

Using Geographic Information Systems to measure retail food environments: Discussion of methodological considerations and a proposed reporting checklist (Geo-FERN).

PubMed

Wilkins, Emma L; Morris, Michelle A; Radley, Duncan; Griffiths, Claire

2017-03-01

Geographic Information Systems (GIS) are widely used to measure retail food environments. However the methods used are hetrogeneous, limiting collation and interpretation of evidence. This problem is amplified by unclear and incomplete reporting of methods. This discussion (i) identifies common dimensions of methodological diversity across GIS-based food environment research (data sources, data extraction methods, food outlet construct definitions, geocoding methods, and access metrics), (ii) reviews the impact of different methodological choices, and (iii) highlights areas where reporting is insufficient. On the basis of this discussion, the Geo-FERN reporting checklist is proposed to support methodological reporting and interpretation. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Project on Elite Athlete Commitment (PEAK): III. An examination of the external validity across gender, and the expansion and clarification of the Sport Commitment Model.

PubMed

Scanlan, Tara K; Russell, David G; Magyar, T Michelle; Scanlan, Larry A

2009-12-01

The Sport Commitment Model was further tested using the Scanlan Collaborative Interview Method to examine its generalizability to New Zealand's elite female amateur netball team, the Silver Ferns. Results supported or clarified Sport Commitment Model predictions, revealed avenues for model expansion, and elucidated the functions of perceived competence and enjoyment in the commitment process. A comparison and contrast of the in-depth interview data from the Silver Ferns with previous interview data from a comparable elite team of amateur male athletes allowed assessment of model external validity, tested the generalizability of the underlying mechanisms, and separated gender differences from discrepancies that simply reflected team or idiosyncratic differences.

The aquatic fern Azolla as a natural plant-factory for ammonia removal from fish-breeding fresh wastewater.

PubMed

Carlozzi, Pietro; Padovani, Giulia

2016-05-01

This study has investigated the potential of an Azolla-Anabaena symbiosis, a marriage between the cyanobacterium Anabaena azollae and the aquatic fern (Azolla), to remove ammonia from freshwater fish breeding areas. Experiments were carried out under artificial light of 20, 70, and 140 μmol m(-2) s(-1). We investigated three different water temperatures for the growing Azolla, ranging from sub-optimal to optimal temperatures (15, 22, and 28 °C). The capability of Azolla to remove ammonia from wastewater was demonstrated, and the highest ammonia concentration tolerated by the symbiosis between Azolla-anabaena without any toxic effect on the aquatic ferns was ascertained. The shortest time taken to remove ammonia from wastes, 2.5 cm deep and at 28 °C, was 40 min. The ammonia removal rate (A RR) was both light and temperature dependent and the highest rate (6.394 h(-1)) was attained at light intensity of 140 μmol m(-2) s(-1) and at a temperature of 28 °C; the lowest (0.947 h(-1)) was achieved at 20 μmol m(-2) s(-1) and 15 °C. The depth of the fish-wastewater pool also affected the A RR with the relation between A RR and the depth being a hyperbolic function.

A free-access online key to identify Amazonian ferns.

PubMed

Zuquim, Gabriela; Tuomisto, Hanna; Prado, Jefferson

2017-01-01

There is urgent need for more data on species distributions in order to improve conservation planning. A crucial but challenging aspect of producing high-quality data is the correct identification of organisms. Traditional printed floras and dichotomous keys are difficult to use for someone not familiar with the technical jargon. In poorly known areas, such as Amazonia, they also become quickly outdated as new species are described or ranges extended. Recently, online tools have allowed developing dynamic, interactive, and accessible keys that make species identification possible for a broader public. In order to facilitate identifying plants collected in field inventories, we developed an internet-based free-access tool to identify Amazonian fern species. We focused on ferns, because they are easy to collect and their edaphic affinities are relatively well known, so they can be used as an indicator group for habitat mapping. Our key includes 302 terrestrial and aquatic entities mainly from lowland Amazonian forests. It is a free-access key, so the user can freely choose which morphological features to use and in which order to assess them. All taxa are richly illustrated, so specimens can be identified by a combination of character choices, visual comparison, and written descriptions. The identification tool was developed in Lucid 3.5 software and it is available at http://keyserver.lucidcentral.org:8080/sandbox/keys.jsp.

Molecular Phylogeny of the Cliff Ferns (Woodsiaceae: Polypodiales) with a Proposed Infrageneric Classification

PubMed Central

Zhang, Xianchun; Xiang, Qiaoping

2015-01-01

The cliff fern family Woodsiaceae has experienced frequent taxonomic changes at the familial and generic ranks since its establishment. The bulk of its species were placed in Woodsia, while Cheilanthopsis, Hymenocystis, Physematium, and Protowoodsia are segregates recognized by some authors. Phylogenetic relationships among the genera of Woodsiaceae remain unclear because of the extreme morphological diversity and inadequate taxon sampling in phylogenetic studies to date. In this study, we carry out comprehensive phylogenetic analyses of Woodsiaceae using molecular evidence from four chloroplast DNA markers (atpA, matK, rbcL and trnL–F) and covering over half the currently recognized species. Our results show three main clades in Woodsiaceae corresponding to Physematium (clade I), Cheilanthopsis–Protowoodsia (clade II) and Woodsia s.s. (clade III). In the interest of preserving monophyly and taxonomic stability, a broadly defined Woodsia including the other segregates is proposed, which is characterized by the distinctive indument and inferior indusia. Therefore, we present a new subgeneric classification of the redefined Woodsia based on phylogenetic and ancestral state reconstructions to better reflect the morphological variation, geographic distribution pattern, and evolutionary history of the genus. Our analyses of the cytological character evolution support multiple aneuploidy events that have resulted in the reduction of chromosome base number from 41 to 33, 37, 38, 39 and 40 during the evolutionary history of the cliff ferns. PMID:26348852

Light-Absorbing Brown Carbon Aerosol Constituents from Combustion of Indonesian Peat and Biomass.

PubMed

Budisulistiorini, Sri Hapsari; Riva, Matthieu; Williams, Michael; Chen, Jing; Itoh, Masayuki; Surratt, Jason D; Kuwata, Mikinori

2017-04-18

Light-absorbing brown carbon (BrC) constituents of organic aerosol (OA) have been shown to significantly absorb ultraviolet (UV) and visible light and thus impact radiative forcing. However, molecular identification of the BrC constituents is still limited. In this study, we characterize BrC constituents at the molecular level in (i) aerosols emitted by combustion of peat, fern/leaf, and charcoal from Indonesia and (ii) ambient aerosols collected in Singapore during the 2015 haze episode. Aerosols were analyzed using ultra performance liquid chromatography instrument interfaced to a diode array detector and electrospray ionization high-resolution quadrupole time-of-flight mass spectrometer operated in the negative ion mode. In the laboratory-generated aerosols, we identified 41 compounds that can potentially absorb near-UV and visible wavelengths, such as oxygenated-conjugated compounds, nitroaromatics, and S-containing compounds. The sum of BrC constituents in peat, fern/leaf, and charcoal burning aerosols are 16%, 35%, and 28% of the OA mass, respectively, giving an average contribution of 24%. On average, the BrC constituents account for 0.4% of the ambient OA mass; however, large uncertainties in mass closure remain because of the lack of authentic standards. This study highlights the potential of light-absorbing BrC OA constituents from peat, fern/leaf, and charcoal burning and their importance in the atmosphere.

Copper uptake by Pteris melanocaulon Fée from a Copper-Gold mine in Surigao del Norte, Philippines.

PubMed

De la Torre, Joseph Benjamin B; Claveria, Rene Juna R; Perez, Rubee Ellaine C; Perez, Teresita R; Doronila, Augustine I

2016-01-01

The ability of some plants to take up metal contaminants in the soil has been of increasing interest as an environmental approach to pollution clean-up. This study aimed to assess the ability of Pteris melanocaulon for copper(Cu) uptake by determining the Cu levels in the fern vis-à-vis surrounding soil and the location of Cu accumulation within its biomass. It also aimed to add information to existing literature as P. melanocaulon are found to be less documented compared to other fern metal accumulators, such as P. vittata. The P. melanocaulon found in the Suyoc Pit of a Copper-Gold mine in Placer, Surigao del Norte, Philippines exhibited a high Bioaccumulation Factor(BF) of 4.04 and a low Translocation Factor(TF) of 0.01, suggesting more Cu accumulation in the roots (4590.22 ± 385.66 µg g(-1) Cu). Noteworthy was the Cu concentration in the rhizome which was also high (3539.44 ± 1696.35 µg g(-1) Cu). SEM/EDX analyses of the Cu content in the roots indicated high elemental %Cu in the xylem (6.95%) than in the cortex (2.68%). The high Cu content in the roots and rhizomes and the localization of Cu in the xylem manifested a potential utilization of the fern as a metallophyte for rhizofiltration and phytostabilization.

Changes to Cretaceous surface fire behaviour influenced the spread of the early angiosperms.

PubMed

Belcher, Claire M; Hudspith, Victoria A

2017-02-01

Angiosperms evolved and diversified during the Cretaceous period. Early angiosperms were short-stature weedy plants thought to have increased fire frequency and mortality in gymnosperm forest, aiding their own expansion. However, no explorations have considered whether the range of novel fuel types that diversified throughout the Cretaceous also altered fire behaviour, which should link more strongly to mortality than fire frequency alone. We measured ignitability and heat of combustion in analogue Cretaceous understorey fuels (conifer litter, ferns, weedy and shrubby angiosperms) and used these data to model palaeofire behaviour. Variations in ignition, driven by weedy angiosperms alone, were found to have been a less important feedback to changes in Cretaceous fire activity than previously estimated. Our model estimates suggest that fires in shrub and fern understories had significantly greater fireline intensities than those fuelled by conifer litter or weedy angiosperms, and whilst fern understories supported the most rapid fire spread, angiosperm shrubs delivered the largest amount of heat per unit area. The higher fireline intensities predicted by the models led to estimates of enhanced scorch of the gymnosperm canopy and a greater chance of transitioning to crown fires. Therefore, changes in fire behaviour driven by the addition of new Cretaceous fuel groups may have assisted the angiosperm expansion. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

Embolism spread in the primary xylem of Polystichum munitum: implications for water transport during seasonal drought.

PubMed

Brodersen, Craig R; Rico, Christopher; Guenni, Orlando; Pittermann, Jarmila

2016-02-01

Xylem network structure and function have been characterized for many woody plants, but less is known about fern xylem, particularly in species endemic to climates where water is a limiting resource for months at a time. We characterized seasonal variability in soil moisture and frond water status in a common perennial fern in the redwood understory of a costal California, and then investigated the consequences of drought-induced embolism on vascular function. Seasonal variability in air temperature and soil water content was minimal, and frond water potential declined slowly over the observational period. Our data show that Polystichum munitum was protected from significant drought-induced hydraulic dysfunction during this growing season because of a combination of cavitation resistant conduits (Air-seeding threshold (ASP) = -1.53 MPa; xylem pressure inducing 50% loss of hydraulic conductivity (P50 ) = -3.02 MPa) and a soil with low moisture variability. High resolution micro-computed tomography (MicroCT) imaging revealed patterns of embolism formation in vivo for the first time in ferns providing insight into the functional status of the xylem network under drought conditions. Together with stomatal conductance measurements, these data suggest that P. munitum is adapted to tolerate drier conditions than what was observed during the growing season. © 2015 John Wiley & Sons Ltd.

A free-access online key to identify Amazonian ferns

PubMed Central

Zuquim, Gabriela; Tuomisto, Hanna; Prado, Jefferson

2017-01-01

Abstract There is urgent need for more data on species distributions in order to improve conservation planning. A crucial but challenging aspect of producing high-quality data is the correct identification of organisms. Traditional printed floras and dichotomous keys are difficult to use for someone not familiar with the technical jargon. In poorly known areas, such as Amazonia, they also become quickly outdated as new species are described or ranges extended. Recently, online tools have allowed developing dynamic, interactive, and accessible keys that make species identification possible for a broader public. In order to facilitate identifying plants collected in field inventories, we developed an internet-based free-access tool to identify Amazonian fern species. We focused on ferns, because they are easy to collect and their edaphic affinities are relatively well known, so they can be used as an indicator group for habitat mapping. Our key includes 302 terrestrial and aquatic entities mainly from lowland Amazonian forests. It is a free-access key, so the user can freely choose which morphological features to use and in which order to assess them. All taxa are richly illustrated, so specimens can be identified by a combination of character choices, visual comparison, and written descriptions. The identification tool was developed in Lucid 3.5 software and it is available at http://keyserver.lucidcentral.org:8080/sandbox/keys.jsp. PMID:28781548

Phylogeny and character evolution of the fern genus Tectaria (Tectariaceae) in the Old World inferred from chloroplast DNA sequences.

PubMed

Ding, Hui-Hui; Chao, Yi-Shan; Callado, John Rey; Dong, Shi-Yong

2014-11-01

In this study we provide a phylogeny for the pantropical fern genus Tectaria, with emphasis on the Old World species, based on sequences of five plastid regions (atpB, ndhF plus ndhF-trnL, rbcL, rps16-matK plus matK, and trnL-F). Maximum parsimony, maximum likelihood, and Bayesian inference are used to analyze 115 individuals, representing ca. 56 species of Tectaria s.l. and 36 species of ten related genera. The results strongly support the monophyly of Tectaria in a broad sense, in which Ctenitopsis, Hemigramma, Heterogonium, Psomiocarpa, Quercifilix, Stenosemia, and Tectaridium should be submerged. Such broadly circumscribed Tectaria is supported by the arising pattern of veinlets and the base chromosome number (x=40). Four primary clades are well resolved within Tectaria, one from the Neotropic (T. trifoliata clade) and three from the Old World (T. subtriphylla clade, Ctenitopsis clade, and T. crenata clade). Tectaria crenata clade is the largest one including six subclades. Of the genera previously recognized as tectarioid ferns, Ctenitis, Lastreopsis, and Pleocnemia, are confirmed to be members in Dryopteridaceae; while Pteridrys and Triplophyllum are supported in Tectariaceae. To infer morphological evolution, 13 commonly used characters are optimized on the resulting phylogenetic trees and in result, are all homoplastic in Tectaria. Copyright © 2014 Elsevier Inc. All rights reserved.

Sensitivity of three tree ferns during their first phase of life to the variation of solar radiation and water availability in a Mexican cloud forest.

PubMed

Riaño, Karolina; Briones, Oscar

2015-09-01

Regeneration niche differentiation promotes species coexistence and diversity; however, the ecological implications for the initial life phases of the majority of pteridophytes are unknown. We analyzed the sensitivity of gametophytes and juvenile sporophytes of the tree ferns Alsophila firma, Cyathea divergens, and Lophosoria quadripinnata to variation in light and water availability. We evaluated gametophyte desiccation tolerance using saturated salt solutions and gametophyte solar radiation tolerance by direct exposure. We also transplanted juvenile sporophytes in environments with 7% and 23% canopy openness and two watering levels. The response of photosynthetic efficiency and water content suggest that the gametophytes of the three species require high relative humidity, tolerate direct solar radiation for up to 30 min and that the response is not species-dependent. Sporophyte size and gas exchange were greater in the more open site, but decreased watering had a lesser effect on these variables in the more closed site. Relative growth rate correlated with the net assimilation rate and leaf weight ratio. Juvenile sporophytes of A. firma were more shade tolerant, while those of C. divergens and L. quadripinnata acclimatized to both environments. Specialization to humid habitats in the tree fern gametophyte restricts the species to humid forests, while differences in the plasticity of the sporophyte facilitate coexistence of the species. © 2015 Botanical Society of America.

Comparison of the petrography, palynology and paleobotany of the Stockton coal bed, West Virginia and implications for paleoenvironmental interpretations

USGS Publications Warehouse

Pierce, B.S.; Stanton, R.W.; Eble, C.F.

1993-01-01

The Stockton coal bed (Middle Pennsylvanian) is a relatively high ash coal composed primarily of moderately thin banded, sparsely thin banded, and nonbanded coal (splint and cannel coal). Comparisons of petrographic, palynologic, and paleobotanic data gathered from the same sample sets from a single column of the Stockton coal bed indicate that compositional correspondences among the sets exist regardless of coal type. Some correspondences are believed to exist because of original plant constituents and others because of the paleoenvironment of peat formation. Using some combination of these data is critical when interpreting paleoenvironmental conditions because (1) a direct correspondence is lacking between many of the data and (2) each of the three data sets provides a unique and important perspective on the paleomire. The Stockton paleomire in the area of this study supported a diverse flora that consisted of both small and arboreous lycopsids, small ferns and tree ferns, calamites, cordaites, and pteridosperms. There appear to have been two successions of Lycospora spore-dominated, vitrinite-rich, liptinite-poor peat formation, which were followed by inertinite-rich peat formation marked by a tree fern-dominant spore assemblage and abundant unidentifiable plant tissues. These are interpreted to be two water-laden or topogenous peat formational stages followed by slightly domed, better drained peat formation. ?? 1993.

In vitro digestibility study of some plant protein sources as aquafeed for carps Labeo rohita and Cyprinus carpio using pH-Stat method.

PubMed

Sharma, Jai Gopal; Kumar, Ashok; Saini, Deepak; Targay, Nawang Lendup; Khangembam, Bronson Kumar; Chakrabarti, Rina

2016-09-01

Aquaculture, as a promising food industry, is expected to meet the demand for quality food from the increasing human population. As the diet is critical for feeding farm fish, such a faster growth in the industry is destined to create stress in the fishmeal market to supply diets to the tune. In this context, here, we studied the protein content of 20 plant ingredients, including aquatic weeds, cereals, pulses and oil-cakes using micro-Kjeldahl method and evaluated in vitro digestibility of these ingredients for rohu Labeo rohita and common carp Cyprinus carpio using pH-Stat method. The protein contents of water fern, duckweed, almond oil-cake and soybean product were 20.81, 39.75, 47.78 and 57.48%, respectively. Species-specific digestibility was found for the same plant ingredient. The degree of hydrolysis for water fern, duck weed, almond oil-cake and soybean product were 14.17, 4.80, 17.30 and 3.57%, respectively for rohu and 4.58, 6.03, 12.17 and 3.35%, respectively for common carp. This study showed that incorporation of water fern and almond oil-cake in the diet of rohu, and duck weed and almond oil-cake in the diet of common carp are beneficial considering their protein content and digestibility. These are cost-effective, protein-rich feed ingredients for aquafeed.

36 CFR 223.216 - Special Forest Products definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

..., Christmas trees, cones, ferns, firewood, forbs, fungi (including mushrooms), grasses, mosses, nuts, pine straw, roots, sedges, seeds, transplants, tree sap, wildflowers, fence material, mine props, posts and...

40 CFR 170.3 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

..., and fiber plants; trees; turfgrass; flowers, shrubs; ornamentals; and seedlings. Chemigation means the... outdoor production of any agricultural plant to produce cut flowers and ferns or plants that will be used...

40 CFR 170.3 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

..., and fiber plants; trees; turfgrass; flowers, shrubs; ornamentals; and seedlings. Chemigation means the... outdoor production of any agricultural plant to produce cut flowers and ferns or plants that will be used...

40 CFR 170.3 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

..., and fiber plants; trees; turfgrass; flowers, shrubs; ornamentals; and seedlings. Chemigation means the... outdoor production of any agricultural plant to produce cut flowers and ferns or plants that will be used...

40 CFR 170.3 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

..., and fiber plants; trees; turfgrass; flowers, shrubs; ornamentals; and seedlings. Chemigation means the... outdoor production of any agricultural plant to produce cut flowers and ferns or plants that will be used...

40 CFR 170.3 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

..., and fiber plants; trees; turfgrass; flowers, shrubs; ornamentals; and seedlings. Chemigation means the... outdoor production of any agricultural plant to produce cut flowers and ferns or plants that will be used...

ERLN Biological Focus Area

EPA Pesticide Factsheets

The Environmental Response Laboratory Network supports the goal to increase national capacity for biological analysis of environmental samples. This includes methods development and verification, technology transfer, and collaboration with USDA, FERN, CDC.

Arsenic speciation for the phytoremediation by the Chinese brake fern, Pteris vittata.

PubMed

Shoji, R; Yajima, R; Yano, Y

2008-01-01

Arsenic (As) speciation for the phytoremediation by the Chinese brake fern was studied. In particular, the mechanism of how plants induce compounds containing thiol (SH) and proteins by As exposure in terms of the relationship between As and phosphate uptaken into plant cells was examined. Pteris vittata callus could efficiently reduce As(V) to As(III) by the rapid introduction of reductase and synthesize thiols leading to phytochelatins production. Furthermore, Pteris vittata could control phosphate concentration in the cells corresponding to the concentration of arsenite and arsenate. To our best knowledge, this is the first report to show the mechanisms of such high As tolerance of Pteris vittata using their callus in terms of in vitro approach for the analysis of As speciation and metabolism route.

Phytoremediation of an arsenic-contaminated site using Pteris vittata L. and Pityrogramma calomelanos var. austroamericana: a long-term study.

PubMed

Niazi, Nabeel Khan; Singh, Balwant; Van Zwieten, Lukas; Kachenko, Anthony George

2012-09-01

This field study investigated the phytoremediation potential of two arsenic (As) hyperaccumulating fern species, Pityrogramma calomelanos var. austroamericana and Pteris vittata over 27-month duration at a disused As-contaminated cattle-dip site located at Wollongbar, NSW, Australia. Ferns planted in January 2009 were harvested following 10, 22 and 27 months of growth. A detailed soil sampling was undertaken in June 2009 (initial, n = 42 per plot) and limited sampling in April 2011 (after 27 months, n = 15 per plot) to measure total and phosphate-extractable As concentrations in soil at 0 - 20-, 20 - 40- and 40 - 60-cm depths. The choice of the limited number of samples was considered sufficient to estimate the changes in soil As concentration following phytoremediation based on a geostatistical model. The average frond dry biomass, As concentration and As uptake were significantly (P < 0.001 - 0.05) greater in P. calomelanos var. austroamericana than P. vittata, at all three harvests (1.6 - 4.3, 1.3 - 1.5 and 2.2 - 5.7 times, respectively). After 27-months of growth, P. calomelanos var. austroamericana removed 8,053 mg As (i.e. cumulative over three harvests) in plot B (25.4 kg As ha(-1)) that was 2.65 times higher than that depleted by P. vittata (3,042 mg As in plot A (9.7 kg As ha(-1))). The cumulative frond As uptake data of the two fern species revealed that P. calomelanos var. austroamericana extracted 1.7 - 3.9 % and P. vittata removed 0.53 - 1.5 % of total As from soil at three depths. However, for the surface (0 - 20 cm) and subsurface (40 - 60 cm) layers, the (post-experiment) soil As data indicated that total As concentration in soil was reduced by 49 and 63 % (P < 0.05), respectively, using P. calomelanos var. austroamericana; and 17 and 15 % (P > 0.05), respectively, by P. vittata. Our results show that phytoremediation time based on observed changes in soil As based on limited sampling is not reliable; hence, it is recommended that the frond As uptake should be considered in order to evaluate the phytoremediation efficiency of the two fern species at the experimental site. Using As uptake of the two fern species, we estimate that with P. calomelanos var. austroamericana it would take 55 - 125 years to decrease mean total As content below the ecological investigation level (20 mg kg(-1)) in the surface and subsurface soils, whereas with P. vittata 143 - 412 years would be required to achieve this target.

7 CFR 340.1 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-01-01

... form of any member of the plant kingdom 3 including, but not limited to, eukaryotic algae, mosses, club mosses, ferns, angiosperms, gymnosperms, and lichens (which contain algae) including any parts (e.g...

7 CFR 340.1 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-01-01

... form of any member of the plant kingdom 3 including, but not limited to, eukaryotic algae, mosses, club mosses, ferns, angiosperms, gymnosperms, and lichens (which contain algae) including any parts (e.g...

7 CFR 340.1 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-01-01

... form of any member of the plant kingdom 3 including, but not limited to, eukaryotic algae, mosses, club mosses, ferns, angiosperms, gymnosperms, and lichens (which contain algae) including any parts (e.g...

Palynology of the Lost Branch Formation of Kansas - New insights on the major floral transition at the Middle-Upper Pennsylvanian boundary

USGS Publications Warehouse

Peppers, R.A.

1997-01-01

Palynological assemblages from two outcrops of the upper part of the Memorial Formation, the Lost Branch Formation, and the overlying Hepler unit in Kansas were examined to discover which stratigraphic interval marks the change from the lycopod-dominated coal swamp floras of Middle Pennsylvanian (Westphalian D) age to the fern-dominated coal swamp floras of Late Pennsylvanian (Stephanian) age. The Lost Branch Formation underlies the Pleasanton Group, whose base is recognized as the Middle-Upper Pennsylvanian boundary in the Midcontinent. The outcrops include the youngest Middle Pennsylvanian coal (Dawson), just below the Lost Branch Formation, and the oldest Upper Pennsylvanian coal ('Hepler') within the Pleasanton Group. Lycospora dominates the spore assemblage in the Middle Pennsylvanian (Desmoinesian) Dawson coal in the Memorial Shale and is abundant in shale between the coal and just below the Glenpool limestone bed at the top of the Lost Branch Formation. It is rare between the limestone and the Upper Pennsylvanian (Missourian) 'Hepler' coal. Granasporites medius and Thymospora pseudothiessenii disappear below the limestone. The 'Hepler' coal is dominated by fern and seed fern spores Cyclogranisporites and Apiculatasporites, and the sphenopsid spore Calamospora is third in abundance. Florinites, Potonieisporites and other gymnospermic monosaccate pollen are abundant between the two coals. Bisaccate conifer-like pollen, such as Protohaploxipinus, are most common between the Dawson coal and Glenpool limestone, but Wilsonites, which is thought to have been produced by seed ferns, is very abundant from the Glenpool limestone to the 'Hepler' coal. On the basis of macroinvertebrate evidence, the Glenpool limestone is Middle Pennsylvanian in age, but the palynological evidence indicates that the floral change took place slightly before deposition of the limestone. Thus, the major change in climate that occurred near the Middle-Upper Pennsylvanian boundary apparently affected the floras earlier than the faunas. The floral change cannot be explained as resulting from a major marine regression and hiatus because the change is recorded in a marine section within a single transgressive-regressive sequence.

Light and desiccation responses of some Hymenophyllaceae (filmy ferns) from Trinidad, Venezuela and New Zealand: poikilohydry in a light-limited but low evaporation ecological niche

PubMed Central

Proctor, Michael C. F.

2012-01-01

Background and Aims Hymenophyllaceae (filmy ferns) are typically plants of shady, constantly moist habitats. They attain greatest species diversity and biomass in humid tropical montane forests and temperate hyperoceanic climates. This paper presents ecophysiological data bearing on their worldwide ecological niche space and its limits. Methods Chlorophyll fluorescence was used to monitor recovery in desiccation experiments, and for measurements of 95 % saturating irradiance [photosynthetic photon flux density (PPFD95 %)] of photosynthetic electron flow and other parameters, in the New Zealand Hymenophyllum sanguinolentum, and three species each of Hymenophyllum and Trichomanes from forests in Trinidad and Venezuela. Key Results Hymenophyllum sanguinolentum was comparable in desiccation tolerance and light responses with the European species. The more common species in the two tropical forests showed PPFD95 % >100 µmol m−2 s−1, and withstood moderate desiccation (–40 MPa) for several days. The four most shade-adapted species had PPFD95 % ≤51 µmol m−2 s−1, and were sensitive to even mild and brief desiccation (–22 MPa for 3 d). Conclusions Light and desiccation responses of filmy ferns can be seen as an integrated package. At low light and windspeed in humid forests, net radiation and saturation deficit are low, and diffusion resistance high. Water loss is slow and can be supported by modest conduction from the sub-stratum. With higher irradiance, selection pressure for desiccation tolerance increases progressively. With low light and high humidity, the filmy fern pattern of adaptation is probably optimal, and the vascular plant leaf with mesophyll and stomata offers no advantage in light capture, water economy or CO2 uptake. Trade-offs between light adaptation and desiccation tolerance, and between stem conduction and water absorption through the leaf surface, underlie adaptive radiation and niche differentiation of species within the family. Hymenophyllaceae are a rare example of an evolutionary shift of adaptive strategy from typical vascular plant adaptation to the poikilohydry most typical of bryophytes. PMID:22334496

Does Hawaiian native forest conserve water? Lower uptake rates at tree and stand scale by Metrosideros polymorpha relative to plantation species

NASA Astrophysics Data System (ADS)

Kagawa, A. K.; Sack, L.; Duarte, T. K.; James, S. A.

2007-12-01

Native plants are often claimed to be conservative water users that enhance groundwater recharge compared to faster-growing non-native species that tend to dominate watersheds. This argument would have implications for motivating conservation and restoration of native forest in Hawai'i. However, few studies have examined differences in native and non-native plant transpiration (water use) at species or at stand level. Our aim was determine whether species matter to stand-level water use. We measured plant transpiration in a continuous mosaic of native forest and non-native tree plantation in Honaunau, Hawaii, focusing on endemic dominant tree Metrosideros polymorpha, alien timber trees Eucalyptus saligna and Fraxinus uhdei, and dominant understory Cibotium tree ferns. We measured xylem sap flow for six individuals of each species continuously for over eight weeks, and we estimated stand water use by scaling up these measurements using stand sapwood area and tree fern leaf area values obtained through vegetation surveys. Native forest dominant Metrosideros had the lowest rates of whole-tree daily water use at 8 kg day-1 (200kg m-2sapwood day-1), less than half the daily rates for Eucalyptus or Fraxinus; Metrosideros also had the lowest maximum transpiration rates of the three tree species. At the stand level, Fraxinus-dominated stands had higher water use than Eucalyptus- and Metrosideros- dominated stands due to the species' high sap flow rates, five-fold greater sapwood allocation, and the stands' two-fold greater dominant tree density. In Metrosideros-dominated stands, high Cibotium tree fern leaf area contributed to nearly 60% of water use, indicating the fern's critical role in forest water balance. Stand water use was influenced by factors at various scales, including species composition, stem density, tree sizes, and tree species' sapwood allocation, and was affected significantly by understory contributions. These findings highlight the importance of constituent species in forest water use, and in the case of this Hawaiian forest, indicate conservative water use by native forest.

Petrology and palynology of the No. 5 block coal bed, northeastern Kentucky

USGS Publications Warehouse

Hower, J.C.; Eble, C.F.; Rathbone, R.F.

1994-01-01

The upper Middle Pennsylvanian (middle Westphalian D equivalent) No. 5 Block coal bed (Eastern Kentucky Coal Field of the Central Appalachian Basin) is a low-sulfur, compliance coal resource, dominantly comprised of dull, inertinite-rich lithotypes. Ash yields tend to be highly variable in the No. 5 Block, as does bed thickness and frequency of bed splitting. This study describes the petrographic, palynologic and geochemical characteristics of the No. 5 Block coal bed, and reports on some temporal and spatial trends among these parameters in eastern-northeastern Kentucky. Petrographically the No. 5 Block coal is predominated by dull, often high-ash lithotypes, with inertinite contents commonly exceeding 30% (mmf). The coal thins to the north-northwest where it tends to be higher in vitrinite and sulfur content. Representatives of large and small lycopsids and ferns (both tree-like and small varieties) dominate the No. 5 Block coal bed palynoflora. Calamite spores and cordaite pollen also occur but are less abundant. Small lycopsid (Densosporites spp. and related crassicingulate genera) and tree fern (e.g. Punctatisporites minutus, Laevigatosporites globosus) spore taxa are most abundant in dull lithotypes. Bright lithotypes contain higher percentages of arboreous lycopsid spores (Lycospora spp.). Regionally, the No. 5 Block coal contains abundant Torispora securis, a tree fern spore specially adapted for desiccation prevention. This, along with overall high percentages of inertinite macerals, suggest that peat accumulation may have taken place in a seasonally dry (?) paleoclimate. The No. 5 Block coal bed thickens rather dramatically in a NW-SE direction, as does the frequency of coal bed splitting. This phenomenon appears to be related to increased accomodation space in the southeastern portion of the study area, perhaps via penecontemporaneous growth faulting. Maceral and palynomorph variations within the bed correspond with these changes. Thin coal along the northwestern margin tends to be vetrinite rich and contains abundant Lycospora, perhaps reflecting relatively stable peat-forming conditions. Thicker coal to the southeast contains more inertinite, high-ash coal layers, and inorganic partings. Spore floras contain more small lycopsid and tree fern components and are temporally variable, perhaps indicating a more unstable peat-forming environment. ?? 1994.

Historical biogeography of the fern genus Deparia (Athyriaceae) and its relation with polyploidy.

PubMed

Kuo, Li-Yaung; Ebihara, Atsushi; Shinohara, Wataru; Rouhan, Germinal; Wood, Kenneth R; Wang, Chun-Neng; Chiou, Wen-Liang

2016-11-01

The wide geographical distribution of many fern species is related to their high dispersal ability. However, very limited studies surveyed biological traits that could contribute to colonization success after dispersal. In this study, we applied phylogenetic approaches to infer historical biogeography of the fern genus Deparia (Athyriaceae, Eupolypods II). Because polyploids are suggested to have better colonization abilities and are abundant in Deparia, we also examined whether polyploidy could be correlated to long-distance dispersal events and whether polyploidy could play a role in these dispersals/establishment and range expansion. Maximum likelihood and Bayesian phylogenetic reconstructions were based on a four-region combined cpDNA dataset (rps16-matK IGS, trnL-L-F, matK and rbcL; a total of 4252 characters) generated from 50 ingroup (ca. 80% of the species diversity) and 13 outgroup taxa. Using the same sequence alignment and maximum likelihood trees, we carried out molecular dating analyses. The resulting chronogram was used to reconstruct ancestral distribution using the DEC model and ancestral ploidy level using ChromEvol. We found that Deparia originated around 27.7Ma in continental Asia/East Asia. A vicariant speciation might account for the disjunctive distribution of East Asia-northeast North America. There were multiple independent long-distance dispersals to Africa/Madagascar (at least once), Southeast Asia (at least once), south Pacific islands (at least twice), Australia/New Guinea/New Zealand (at least once), and the Hawaiian Islands (at least once). In particular, the long-distance dispersal to the Hawaiian Islands was associated with polyploidization, and the dispersal rate was slightly higher in the polyploids than in diploids. Moreover, we found five species showing recent infraspecific range expansions, all of which took place concurrently with polyploidization. In conclusion, our study provides the first investigation using phylogenetic and biogeographic analyses trying to explore the link between historical biogeography and ploidy evolution in a fern genus and our results imply that polyploids might be better colonizers than diploids. Copyright © 2016 Elsevier Inc. All rights reserved.

Rapid allopolyploid radiation of moonwort ferns (Botrychium; Ophioglossaceae) revealed by PacBio sequencing of homologous and homeologous nuclear regions.

PubMed

Dauphin, Benjamin; Grant, Jason R; Farrar, Donald R; Rothfels, Carl J

2018-03-01

Polyploidy is a major speciation process in vascular plants, and is postulated to be particularly important in shaping the diversity of extant ferns. However, limitations in the availability of bi-parental markers for ferns have greatly limited phylogenetic investigation of polyploidy in this group. With a large number of allopolyploid species, the genus Botrychium is a classic example in ferns where recurrent polyploidy is postulated to have driven frequent speciation events. Here, we use PacBio sequencing and the PURC bioinformatics pipeline to capture all homeologous or allelic copies of four long (∼1 kb) low-copy nuclear regions from a sample of 45 specimens (25 diploids and 20 polyploids) representing 37 Botrychium taxa, and three outgroups. This sample includes most currently recognized Botrychium species in Europe and North America, and the majority of our specimens were genotyped with co-dominant nuclear allozymes to ensure species identification. We analyzed the sequence data using maximum likelihood (ML) and Bayesian inference (BI) concatenated-data ("gene tree") approaches to explore the relationships among Botrychium species. Finally, we estimated divergence times among Botrychium lineages and inferred the multi-labeled polyploid species tree showing the origins of the polyploid taxa, and their relationships to each other and to their diploid progenitors. We found strong support for the monophyly of the major lineages within Botrychium and identified most of the parental donors of the polyploids; these results largely corroborate earlier morphological and allozyme-based investigations. Each polyploid had at least two distinct homeologs, indicating that all sampled polyploids are likely allopolyploids (rather than autopolyploids). Our divergence-time analyses revealed that these allopolyploid lineages originated recently-within the last two million years-and thus that the genus has undergone a recent radiation, correlated with multiple independent allopolyploidizations across the phylogeny. Also, we found strong parental biases in the formation of allopolyploids, with individual diploid species participating multiple times as either the maternal or paternal donor (but not both). Finally, we discuss the role of polyploidy in the evolutionary history of Botrychium and the interspecific reproductive barriers possibly involved in these parental biases. Copyright © 2017 Elsevier Inc. All rights reserved.

Insights into evolution in Andean Polystichum (Dryopteridaceae) from expanded understanding of the cytosolic phosphoglucose isomerase gene.

PubMed

Lyons, Brendan M; McHenry, Monique A; Barrington, David S

2017-07-01

Cytosolic phosphoglucose isomerase (pgiC) is an enzyme essential to glycolysis found universally in eukaryotes, but broad understanding of variation in the gene coding for pgiC is lacking for ferns. We used a substantially expanded representation of the gene for Andean species of the fern genus Polystichum to characterize pgiC in ferns relative to angiosperms, insects, and an amoebozoan; assess the impact of selection versus neutral evolutionary processes on pgiC; and explore evolutionary relationships of selected Andean species. The dataset of complete sequences comprised nine accessions representing seven species and one hybrid from the Andes and Serra do Mar. The aligned sequences of the full data set comprised 3376 base pairs (70% of the entire gene) including 17 exons and 15 introns from two central areas of the gene. The exons are highly conserved relative to angiosperms and retain substantial homology to insect pgiC, but intron length and structure are unique to the ferns. Average intron size is similar to angiosperms; intron number and location in insects are unlike those of the plants we considered. The introns included an array of indels and, in intron 7, an extensive microsatellite array with potential utility in analyzing population-level histories. Bayesian and maximum-parsimony analysis of 129 variable nucleotides in the Andean polystichums revealed that 59 (1.7% of the 3376 total) were phylogenetically informative; most of these united sister accessions. The phylogenetic trees for the Andean polystichums were incongruent with previously published cpDNA trees for the same taxa, likely the result of rapid evolutionary change in the introns and contrasting stability in the exons. The exons code a total of seven amino-acid substitutions. Comparison of non-synonymous to synonymous substitutions did not suggest that the pgiC gene is under selection in the Andes. Variation in pgiC including two additional accessions represented by incomplete sequences provided new insights into reticulate relationships among Andean taxa. Copyright © 2017 Elsevier Inc. All rights reserved.

Wild food plants used by the Tibetans of Gongba Valley (Zhouqu county, Gansu, China)

PubMed Central

2014-01-01

Background The ethnobotany of Tibetans is a seriously under-studied topic. The aim of the study was to investigate knowledge and use of wild food plants in a valley inhabited by Tibetans in the Gannan Tibetan Autonomous Region. Methods The field research was carried out in a wooded mountain valley in 9 neighbouring villages the Zhouqu (Brugchu) county, and comprised 17 interviews with single informants and 14 group interviews, involving 122 people altogether. Results We recorded the use of 81 species of vascular plants from 41 families. Fruits formed the largest category, with 42 species, larger than the wild greens category, with 36 species. We also recorded the culinary use of 5 species of edible flowers, 7 species with underground edible organs and 5 taxa of fungi. On average, 16.2 edible taxa were listed per interview (median – 16). Green vegetables formed the largest category of wild foods (mean – 8.7 species, median – 9 species), but fruits were listed nearly as frequently (mean – 6.9, median – 6). Other categories were rarely mentioned: flowers (mean – 0.2, median – 0), underground edible parts (mean – 0.3, median – 0) and mushrooms (mean – 1.5, – median 1). Wild vegetables are usually boiled and/or fried and served as side-dishes (cai). They are often lacto-fermented. Wild fruits are mainly collected by children and eaten raw, they are not stored for further use. The most widely used wild vegetables are: Eleuterococcus spp., Pteridium aquilinum, Helwingia japonica, Aralia chinensis, Allium victorialis, Pteridium aquilinum, Ixeris chinensis, Thlaspi arvense and Chenopodium album. The culinary use of Caltha palustris as a green vegetable is very interesting. In its raw state, marsh marigold is a toxic plant, due to the presence of protoanemonin. In this area it is dried or lactofermented before use. The most commonly eaten fruits are: Pyrus xerophila, Prunus salicina, Berchemia sinica, Rubus spp. and Eleagnus umbellata. Conclusions The number of wild taxa eaten in the studied valley is relatively large compared to most studies from around the world. However, compared to the northern slope of the Qinling, in Shaanxi, the list is considerably shorter, in spite of the similar methodology applied and similar research effort involved. PMID:24502461

Culturing Fern Gametophytes on Solid Mineral Media for Classroom Study.

ERIC Educational Resources Information Center

Chilton, Glen; Graham, Lane C.

1988-01-01

Described are the techniques and results of using this tissue culture activity. Discusses the advantages of using such techniques in teaching alternation of generation life cycles to biology students. (CW)

An algorithm of adaptive scale object tracking in occlusion

NASA Astrophysics Data System (ADS)

Zhao, Congmei

2017-05-01

Although the correlation filter-based trackers achieve the competitive results both on accuracy and robustness, there are still some problems in handling scale variations, object occlusion, fast motions and so on. In this paper, a multi-scale kernel correlation filter algorithm based on random fern detector was proposed. The tracking task was decomposed into the target scale estimation and the translation estimation. At the same time, the Color Names features and HOG features were fused in response level to further improve the overall tracking performance of the algorithm. In addition, an online random fern classifier was trained to re-obtain the target after the target was lost. By comparing with some algorithms such as KCF, DSST, TLD, MIL, CT and CSK, experimental results show that the proposed approach could estimate the object state accurately and handle the object occlusion effectively.

Fertile organs and in situ spores of a new dipteridaceous fern Hausmannia sinensis from the Jurassic of northern China.

PubMed

Wang, Yongdong; Zhang, Hong

2010-01-22

As a representative fossil member of the dipteridaceous fern, genus Hausmannia was reported worldwide from the Mesozoic strata; however, little is known about the fertile structures, including sporangia and in situ spores, of this genus. In this study, a new species Hausmannia sinensis was identified from the Middle Jurassic of Nei Mongol (Inner Mongolia), northern China. The specimens are compressions and are well preserved with details of sporangia and in situ spores. The leaf laminae are broadly fan-shaped, with an almost entire margin. Primary and lateral veins dichotomously branch to form square or polygonal meshes. Each ultimate mesh bears one to two circular sori of 0.4 mm in diameter. Sori are exindusiate; each sorus contains three to six round to ovoid sporangia. The annulus is developed and oblique, with stomial region present in proximal position. Spores are trilete, circular to oval in shape. Both proximal and distal surfaces are covered with baculate to subverrucate sculptures. Spores range from 20 to 30 microm in diameter (average 28 microm), and are comparable to the dispersed genera Baculatisporites Thomas and Pflug and Apiculatisporis Potonié and Kremp. Hausmannia sinensis represents the first compression species of genus Hausmannia form Eurasia, which shows the combination of well-preserved sori, sporangia, annuli and in situ spore characters, and is therefore helpful for further understanding the diversity and evolution of the Dipteridaceae fern lineage through time.

Fertile organs and in situ spores of a new dipteridaceous fern Hausmannia sinensis from the Jurassic of northern China

PubMed Central

Wang, Yongdong; Zhang, Hong

2010-01-01

As a representative fossil member of the dipteridaceous fern, genus Hausmannia was reported worldwide from the Mesozoic strata; however, little is known about the fertile structures, including sporangia and in situ spores, of this genus. In this study, a new species Hausmannia sinensis was identified from the Middle Jurassic of Nei Mongol (Inner Mongolia), northern China. The specimens are compressions and are well preserved with details of sporangia and in situ spores. The leaf laminae are broadly fan-shaped, with an almost entire margin. Primary and lateral veins dichotomously branch to form square or polygonal meshes. Each ultimate mesh bears one to two circular sori of 0.4 mm in diameter. Sori are exindusiate; each sorus contains three to six round to ovoid sporangia. The annulus is developed and oblique, with stomial region present in proximal position. Spores are trilete, circular to oval in shape. Both proximal and distal surfaces are covered with baculate to subverrucate sculptures. Spores range from 20 to 30 μm in diameter (average 28 μm), and are comparable to the dispersed genera Baculatisporites Thomas and Pflug and Apiculatisporis Potonié and Kremp. Hausmannia sinensis represents the first compression species of genus Hausmannia form Eurasia, which shows the combination of well-preserved sori, sporangia, annuli and in situ spore characters, and is therefore helpful for further understanding the diversity and evolution of the Dipteridaceae fern lineage through time. PMID:19364738

Antioxidant and tyrosinase inhibition activity of the fertile fronds and rhizomes of three different Drynaria species.

PubMed

Tan, Joash Ban Lee; Lim, Yau Yan

2015-09-22

For generations, the rhizomes of Drynaria ferns have been used as traditional medicine in Asia. Despite this, the bioactivities of Drynaria rhizomes and leaves have rarely been studied scientifically. This study evaluates the antioxidant properties of the methanolic extracts of the fertile fronds and rhizomes from three species in this genus: Drynaria quercifolia, Drynaria rigidula and Drynaria sparsisora. The phenolic and flavonoid contents of the samples were respectively quantified with the total phenolic content (TPC) and total flavonoid content (TFC) assays, while the antioxidant activities were determined via measuring the DPPH radical scavenging activity (FRS), ferric reducing power (FRP), ferrous ion chelating (FIC) activity and lipid peroxidation inhibition (LPI). The tyrosinase inhibition activity of all three species was also reported. The fertile fronds of D. quercifolia were found to exhibit the highest overall TPC (2939 ± 469 mg GAE/100 g) and antioxidant activity amongst all the samples, and the fertile fronds of D. quercifolia and D. rigidula exhibited superior TPC and FRP compared to their rhizomes, despite only the latter being widely used in traditional medicine. The fronds of D. quercifolia had high tyrosinase inhibition activity (56.6 ± 5.0 %), but most of the Drynaria extracts showed unexpected tyrosinase enhancement instead, particularly for D. sparsisora's fronds. The high bioactivity of the fertile fronds in the fern species indicate that there is value in further research on the fronds of ferns which are commonly used mostly, or only, for their rhizomes.

N-Methyl Inversion in Pseudo-Pelletierine

NASA Astrophysics Data System (ADS)

Vallejo-López, Montserrat; Ecija, Patricia; Cocinero, Emilio J.; Lesarri, Alberto; Basterretxea, Francisco J.; Fernández, José A.

2016-06-01

We have previously conducted rotational studies of several tropanes, since this bicyclic structural motif forms the core of different alkaloids of pharmaceutical interest. Now we report on the conformational properties and molecular structure of pseudo-pelletierine (9-methyl-9-azabicyclo[3.3.1]nonan-3-one), probed in a jet expansion with Fourier-transform microwave spectroscopy. Pseudo-pelletierine is an azabicycle with two fused six-membered rings, where the N-methyl group can produce inverting axial o equatorial conformations. The two conformations were detected in the rotational spectrum, recorded in the region 6-18 GHz. Unlike tropinone and N-methylpiperidone, where the most stable conformer is equatorial, the axial species was found dominant for pseudo-pelletierine. All monosubstituted isotopic species (13C, 15N and 18O) were identified for the axial conformer, leading to an accurate determination of the effective and substitution structures. An estimation of conformational populations was derived from relative intensities. The experimental results will be compared with ab initio (MP2) and DFT (M06-2X, B3LYP) calculations. E. J. Cocinero, A. Lesarri, P. Écija, J.-U. Grabow, J. A. Fernández, F. Castaño, Phys. Chem. Chem. Phys. 2010, 49, 4503 P. Écija, E. J. Cocinero, A. Lesarri, F. J. Basterretxea, J. A. Fernández, F. Castaño, Chem. Phys. Chem. 2013, 14, 1830 P. Écija, M. Vallejo-Lopez, I. Uriarte, F. J. Basterretxea, A. Lesarri, J. A. Fernández, E. J. Cocinero, submitted 2016

Proteomic analysis of stipe explants reveals differentially expressed proteins involved in early direct somatic embryogenesis of the tree fern Cyathea delgadii Sternb.

PubMed

Domżalska, Lucyna; Kędracka-Krok, Sylwia; Jankowska, Urszula; Grzyb, Małgorzata; Sobczak, Mirosław; Rybczyński, Jan J; Mikuła, Anna

2017-05-01

Using cyto-morphological analysis of somatic embryogenesis (SE) in the tree fern Cyathea delgadii as a guide, we performed a comparative proteomic analysis in stipe explants undergoing direct SE. Plant material was cultured on hormone-free medium supplemented with 2% sucrose. Phenol extracted proteins were separated using two-dimensional gel electrophoresis (2-DE) and mass spectrometry was performed for protein identification. A total number of 114 differentially regulated proteins was identified during early SE, i.e. when the first cell divisions started and several-cell pro-embryos were formed. Proteins were assigned to seven functional categories: carbohydrate metabolism, protein metabolism, cell organization, defense and stress responses, amino acid metabolism, purine metabolism, and fatty acid metabolism. Carbohydrate and protein metabolism were found to be the most sensitive SE functions with the greatest number of alterations in the intensity of spots in gel. Differences, especially in non-enzymatic and structural protein abundance, are indicative for cell organization, including cytoskeleton rearrangement and changes in cell wall components. The highest induced changes concern those enzymes related to fatty acid metabolism. Global analysis of the proteome reveals several proteins that can represent markers for the first 16days of SE induction and expression in fern. The findings of this research improve the understanding of molecular processes involved in direct SE in C. delgadii. Copyright © 2017 Elsevier B.V. All rights reserved.

Genetics Home Reference: epidermal nevus

MedlinePlus

... Lurkin I, Acquadro F, Fernández-Casado A, Zwarthoff EC, Dietmaier W, Baselga E, Parera E, Vicente A, ... M, Stoehr R, Blaszyk H, Hofstaedter F, Zwarthoff EC, Hartmann A. Mosaicism of activating FGFR3 mutations in ...

32 CFR Appendix C to Subpart M of... - Authorized Activities for Maneuver Training Area Access

Code of Federal Regulations, 2012 CFR

2012-07-01

..., blackberries, apples and other vegetation Photography Hiking 2. Yakima Training Center: Military Training (FL...-commercial picking of ferns, mushrooms, blackberries, apples and other vegetation Photography Hiking Note...

32 CFR Appendix C to Subpart M of... - Authorized Activities for Maneuver Training Area Access

Code of Federal Regulations, 2013 CFR

2013-07-01

..., blackberries, apples and other vegetation Photography Hiking 2. Yakima Training Center: Military Training (FL...-commercial picking of ferns, mushrooms, blackberries, apples and other vegetation Photography Hiking Note...

32 CFR Appendix C to Subpart M of... - Authorized Activities for Maneuver Training Area Access

Code of Federal Regulations, 2011 CFR

2011-07-01

..., blackberries, apples and other vegetation Photography Hiking 2. Yakima Training Center: Military Training (FL...-commercial picking of ferns, mushrooms, blackberries, apples and other vegetation Photography Hiking Note...

32 CFR Appendix C to Subpart M of... - Authorized Activities for Maneuver Training Area Access

Code of Federal Regulations, 2014 CFR

2014-07-01

..., blackberries, apples and other vegetation Photography Hiking 2. Yakima Training Center: Military Training (FL...-commercial picking of ferns, mushrooms, blackberries, apples and other vegetation Photography Hiking Note...

Temperature Reconstruction and Biomarker Variation across the Cretaceous-Paleogene Boundary, Mid-Waipara River, New Zealand

NASA Astrophysics Data System (ADS)

Taylor, K. W.; Hollis, C. J.; Pancost, R. D.

2010-12-01

The Cretaceous-Paleogene (K/Pg) boundary marks a catastrophic global extinction event, believed to be caused by an asteroid impact in northern Yucatan. Whilst the extent of mass extinction is well documented, there is ongoing debate about the immediate and longer term climatic and environmental changes triggered by the event. The northern South Island of New Zealand has several records of the K/Pg boundary, representing a range of terrestrial and marine environments. Previous studies of terrestrial palynomorphs and siliceous microfossils from these sections suggested significant cooling and terrestrial vegetation reconfiguration in the earliest Paleocene. Extinctions or local disappearances of thermophilic taxa at the K/Pg boundary are consistent with the hypothesis of a short-lived “impact winter”. The Mid-Waipara K/Pg boundary section, north Canterbury, has been identified as suitable for organic geochemical study because sufficient organic carbon is present in the siliciclastic sediments and is thermally immature. Sediments were deposited in outer shelf to upper slope depths under a neritic watermass. New estimates of sea surface temperature variation based on TEX86 elucidate the relationship between biological and climatic changes that followed the K/Pg event. Within the 0.25 m-thick interval identified as the “fern spike” in basal Paleocene sediments in this section there is no indication of a significant change in temperature relative to the Cretaceous (22-25°C). Foraminiferal and radiolarian biostratigraphy indicates that this interval spans ~100 kyrs and includes a fern succession from colonising ground ferns to tree ferns, the latter suggesting a temperate, humid climate. The transition from ferns to a conifer-dominated pollen assemblage corresponds with a remarkable decrease in temperature recorded in the TEX86 record. These cool temperatures persist over 10 m. The dominant conifer pollen type over this interval is Phyllocladites mawsonii, indicative of cool-temperate conditions. Preliminary biostratigraphic correlation suggests that this interval is condensed, possibly truncated at the base, and may be correlated to a more expanded biogenic silica-rich interval in the pelagic K/Pg boundary sections in eastern Marlborough, northeastern South Island. These results support siliceous microfossil evidence for pronounced cooling in early Paleocene in New Zealand. Organic biomarker records provide further insight into terrestrial and marine ecological reconfiguration through the K/Pg boundary transition at Mid-Waipara River. Major reorganisations of the phytoplankton and archaeal communities are indicated by pronounced changes in sterol and tetraether distributions following the K/Pg boundary. Transient disruption of higher plants at the boundary is verified by suppression of n-alkane and triterpenoid biomarker concentrations, succeeded by a gradual recovery into the Early Paleocene. The scenario envisaged may be summarised as climate instability following the K/Pg boundary event, culminating in cool climatic conditions and a strengthened local upwelling regime leading to widespread deposition of diatom-rich siliceous sediments, lasting for around 1 Myr.

Census of U.S. Civil Aircraft, Calendar Year 1985.

DTIC Science & Technology

1985-12-31

LIMITED BN-2B-2 10 5’ 2 0 1 BN-26-21 10 51 2 0 1 1 F/W MULTI REC. ENG 51 0 2 2 TOTAL 0 2 2 . PINE AIR % SUPER V 4 51 2 0 1 F/W MULTI REC. ENG 51 0 1 1... Plymouth 32 12 15 2 2 1Pocahontas 22 7 13 1 1Polk 405 104 180 36 17 23 1 8 3 2 1 30 *Pottawatta 68 12 39 7 2 6 3 0 . Powes"In 21 7 10 2 2 Ringgold 3 2 1...2 Ballard 3 2 Barren 22 4 14 1 3 Bath 2 1 Bell 12 1 8 2 Boone 17 4 9 1 1 2 Bourbon 5 1 3 Boyd 37 8 14 6 2 2 2 Boyle 12 4 Bracken 3 2 1 Breatnitt 9

Genetics Home Reference: tibial muscular dystrophy

MedlinePlus

... I, Eymard B, Pardal-Fernández JM, Hammouda el-H, Richard I, Illa I, Udd B. Truncating mutations ... Citation on PubMed Hackman P, Vihola A, Haravuori H, Marchand S, Sarparanta J, De Seze J, Labeit S, Witt ...

Partial Planning Reinforcement Learning

DTIC Science & Technology

2012-08-31

Research Office P.O. Box 12211 Research Triangle Park, NC 27709-2211 15. SUBJECT TERMS Reinforcement Learning, Bayesian Optimization, Active ... Learning , Action Model Learning, Decision Theoretic Assistance Prasad Tadepalli, Alan Fern Oregon State University Office of Sponsored Programs Oregon State

Bierman {ital et al.}Reply:

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

Bierman, J.D.; Chan, P.; Liang, J.F.

1997-05-01

reply to the Comment by C.H.Dasso et al., Phys. Rev. Lett. 78,XXX(1997). A Reply to the Comment by C.H. Dasso and J. Fern{acute a}ndez-Niello. {copyright} {ital 1997} {ital The American Physical Society}

Cryopreservation of spores of Dicksonia sellowiana: an endangered tree fern indigenous to South and Central America.

PubMed

Rogge, G D; Viana, A M; Randi, A M

2000-01-01

Spores of Dicksonia sellowiana (Presl.) Hook., an endangered tree fern, were stored in liquid nitrogen. Surface sterilized spores were placed in 1 ml sterile polypropylene cryotubes and were plunged into liquid nitrogen cryo-cans for 15 minutes, 15 days, 1 month and 3 months. In all, of the treatments the percentage of germination was higher than the control (fresh spores). Germination in Dyer and MS media supplement with 10 (-7) M and 5 x 10(-7) M BA was also promoted as comparing to control. There was no difference between the germination of spores thawed rapidly in a water bath at 45 degree C during 5 minutes or slowly at room temperature. Cryopreservation seems to promote germination of some dormant spores of D. sellowiana. The pre-treatment in cryoprotective solution of dimethyl sulphoxide 15%(v/v) in 1 M glycerol inhibited the germination of cryopreserved spores

A Powerful Test for Comparing Multiple Regression Functions.

PubMed

Maity, Arnab

2012-09-01

In this article, we address the important problem of comparison of two or more population regression functions. Recently, Pardo-Fernández, Van Keilegom and González-Manteiga (2007) developed test statistics for simple nonparametric regression models: Y(ij) = θ(j)(Z(ij)) + σ(j)(Z(ij))∊(ij), based on empirical distributions of the errors in each population j = 1, … , J. In this paper, we propose a test for equality of the θ(j)(·) based on the concept of generalized likelihood ratio type statistics. We also generalize our test for other nonparametric regression setups, e.g, nonparametric logistic regression, where the loglikelihood for population j is any general smooth function [Formula: see text]. We describe a resampling procedure to obtain the critical values of the test. In addition, we present a simulation study to evaluate the performance of the proposed test and compare our results to those in Pardo-Fernández et al. (2007).

The nature of subslab slow velocity anomalies beneath South America

NASA Astrophysics Data System (ADS)

Portner, Daniel Evan; Beck, Susan; Zandt, George; Scire, Alissa

2017-05-01

Slow seismic velocity anomalies are commonly imaged beneath subducting slabs in tomographic studies, yet a unifying explanation for their distribution has not been agreed upon. In South America two such anomalies have been imaged associated with subduction of the Nazca Ridge in Peru and the Juan Fernández Ridge in Chile. Here we present new seismic images of the subslab slow velocity anomaly beneath Chile, which give a unique view of the nature of such anomalies. Slow seismic velocities within a large hole in the subducted Nazca slab connect with a subslab slow anomaly that appears correlated with the extent of the subducted Juan Fernández Ridge. The hole in the slab may allow the subslab material to rise into the mantle wedge, revealing the positive buoyancy of the slow material. We propose a new model for subslab slow velocity anomalies beneath the Nazca slab related to the entrainment of hot spot material.

Toxicity of Diclofenac in the Fern Azolla filiculoides and the Lichen Xanthoria parietina.

PubMed

Vannini, Andrea; Paoli, Luca; Vichi, Marco; Bačkor, Martin; Bačkorová, Miriam; Loppi, Stefano

2018-03-01

This study investigated the occurrence of toxicity, expressed as damage to the photosynthetic apparatus, in the aquatic fern Azolla filiculoides and the lichen Xanthoria parietina following treatments with diclofenac at different concentrations (0.1, 1, 10 and 100 mg/L) and different exposure times (24, 48, 72 and 240 h). Measurements of photosynthetic efficiency, chlorophyll content and chlorophyll degradation indicated dose- and time-dependent toxicity, since significant differences with control samples as well as among treatments, emerged mainly for the highest concentration (100 mg/L) and the longest time (240 h). In addition, also the mycobiont of the lichen X. parietina showed similar toxic effects, expressed as ergosterol content. The absence of relevant alterations at the lowest concentration (0.1 mg/L) suggested a very limited susceptibility of these species to environmentally relevant levels of this pharmaceutical.

Development and characterization of 27 microsatellite markers for the mangrove fern, Acrostichum aureum (Pteridaceae).

PubMed

Yamamoto, Takashi; Tsuda, Yoshiaki; Mori, Gustavo Maruyama; Cruz, Mariana Vargas; Shinmura, Yoshimi; Wee, Alison K S; Takayama, Koji; Asakawa, Takeshi; Yamakawa, Takeru; Suleiman, Monica; Núñez-Farfán, Juan; Webb, Edward L; Watano, Yasuyuki; Kajita, Tadashi

2016-09-01

Twenty-seven nuclear microsatellite markers were developed for the mangrove fern, Acrostichum aureum (Pteridaceae), to investigate the genetic structure and demographic history of the only pantropical mangrove plant. Fifty-six A. aureum individuals from three populations were sampled and genotyped to characterize the 27 loci. The number of alleles and expected heterozygosity ranged from one to 15 and 0.000 to 0.893, respectively. Across the 26 polymorphic loci, the Malaysian population showed much higher levels of polymorphism compared to the other two populations in Guam and Brazil. Cross-amplification tests in the other two species from the genus determined that seven and six loci were amplifiable in A. danaeifolium and A. speciosum, respectively. The 26 polymorphic microsatellite markers will be useful for future studies investigating the genetic structure and demographic history of of A. aureum, which has the widest distributional range of all mangrove plants.

Ferns, mosses and liverworts as model systems for light-mediated chloroplast movements.

PubMed

Suetsugu, Noriyuki; Higa, Takeshi; Wada, Masamitsu

2017-11-01

Light-induced chloroplast movement is found in most plant species, including algae and land plants. In land plants with multiple small chloroplasts, under weak light conditions, the chloroplasts move towards the light and accumulate on the periclinal cell walls to efficiently perceive light for photosynthesis (the accumulation response). Under strong light conditions, chloroplasts escape from light to avoid photodamage (the avoidance response). In most plant species, blue light induces chloroplast movement, and phototropin receptor kinases are the blue light receptors. Molecular mechanisms for photoreceptors, signal transduction and chloroplast motility systems are being studied using the model plant Arabidopsis thaliana. However, to further understand the molecular mechanisms and evolutionary history of chloroplast movement in green plants, analyses using other plant systems are required. Here, we review recent works on chloroplast movement in green algae, liverwort, mosses and ferns that provide new insights on chloroplast movement. © 2016 John Wiley & Sons Ltd.

Arsenic speciation in tissues of the hyperaccumulator P. calomelanos var. austroamericana using X-ray absorption spectroscopy.

PubMed

Kachenko, Anthony G; Gräfe, Markus; Singh, Balwant; Heald, Steve M

2010-06-15

The fate and chemical speciation of arsenic (As) during uptake, translocation, and storage by the As hyperaccumulating fern Pityrogramma calomelanos var. austroamericana (Pteridaceae) were examined using inductively coupled plasma-atomic emission spectrometry (ICP-AES) and synchrotron-based micro-X-ray absorption near edge structure (micro-XANES) and micro-X-ray fluorescence (micro-XRF) spectroscopies. Chemical analysis revealed total As concentration was ca. 6.5 times greater in young fronds (5845 mg kg(-1) dry weight (DW)) than in old fronds (903 mg kg(-1) DW). In pinnae, As concentration decreased from the base (6822 mg kg(-1) DW) to the apex (4301 mg kg(-1) DW) of the fronds. The results from micro-XANES and micro-XRF of living tissues suggested that more than 60% of arsenate (As(V)) absorbed was reduced to arsenite (As(III)) in roots, prior to transport through vascular tissues as As(V) and As(III). In pinnules, As(III) was the predominant redox species (72-90%), presumably as solvated, oxygen coordinated compounds. The presence of putative As(III)-sulphide (S(2-)) coordination throughout the fern tissues (4-25%) suggests that S(2-) functional groups may contribute in the biochemical reduction of As(V) to As(III) during uptake and transport at a whole-plant level. Organic arsenicals and thiol-rich compounds were not detected in the species and are unlikely to play a role in As hyperaccumulation in this fern. The study provides important insights into homeostatic regulation of As following As uptake in P. calomelanos var. austroamericana.

Biosynthesis of lead nanoparticles by the aquatic water fern, Salvinia minima Baker, when exposed to high lead concentration.

PubMed

Castro-Longoria, E; Trejo-Guillén, K; Vilchis-Nestor, A R; Avalos-Borja, M; Andrade-Canto, S B; Leal-Alvarado, D A; Santamaría, J M

2014-02-01

Salvinia minima Baker is a small floating aquatic fern that is efficient for the removal and storage of heavy metals such as lead and cadmium. In this study, we report that lead removal by S. minima causes large accumulation of lead inside the cells in the form of nanoparticles (PbNPs). The accumulation pattern of lead was analyzed in both, submerged root-like modified fronds (here named "roots"), and in its aerial leaf-like fronds ("leaves"). Analysis by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM) and high resolution transmission electron microscopy (HRTEM) confirmed the biosynthesis of PbNPs by the plant. In both, roots and leaves, PbNPs were found to accumulate almost exclusively at the cell wall and closely associated to the cell membrane. Two types of PbNPs shapes were found in cells of both tissues, those associated to the cell wall were quasi-spherical with 17.2±4.2 nm of diameter, while those associated to the cell membrane/cytoplasm were elongated. Elongated particles were 53.7±29.6 nm in length and 11.1±2.4 nm wide. Infrared spectroscopy (IR) results indicate that cellulose, lignin and pectin are the major components that may be acting as the reducing agents for lead ions; these findings strongly suggest the potential use of this fern to further explore the bio-assisted synthesis of heavy metal nanostructures. Copyright © 2013 Elsevier B.V. All rights reserved.

What can we Expect of High-Resolution Spectroscopies on Carbohydrates?

NASA Astrophysics Data System (ADS)

Cocinero, Emilio J.; Ecija, Patricia; Uriarte, Iciar; Usabiaga, Imanol; Fernández, José A.; Basterretxea, Francisco J.; Lesarri, Alberto; Davis, Benjamin G.

2015-06-01

Carbohydrates are one of the most multifaceted building blocks, performing numerous roles in living organisms. We present several structural investigations on carbohydrates exploiting an experimental strategy which combines microwave (MW) and laser spectroscopies in high-resolution. Laser spectroscopy offers high sensitivity coupled to mass and conformer selectivity, making it ideal for polysaccharides studies. On the other hand, microwave spectroscopy provides much higher resolution and direct access to molecular structure of monosaccharides. This combined approach provides not only accurate chemical insight on conformation, structure and molecular properties, but also benchmarking standards guiding the development of theoretical calculations. In order to illustrate the possibilities of a combined MW-laser approach we present results on the conformational landscape and structural properties of several monosaccharides and oligosaccharides including microsolvation and molecular recognition processes of carbohydrates. E.J. Cocinero, A. Lesarri, P. écija, F.J. Basterretxea, J.-U. Grabow, J.A. Fernández and F. Casta {n}o Angew. Chem. Int. Ed. 51, 3119-3124, 2012. E.J. Cocinero, A. Lesarri, P. écija, Á. Cimas, B.G. Davis, F.J. Basterretxea, J.A. Fernández and F. Casta {n}o J. Am. Chem. Soc. 135, 2845-2852, 2013. E.J. Cocinero, P. Çarçabal, T.D. Vaden, J.P. Simons and B.G. Davis Nature 469, 76-80, 2011. C.S. Barry, E.J. Cocinero, P. Çarçabal, D.P. Gamblin, E.C. Stanca-Kaposta, S. M. Fernández-Alonso, S. Rudić, J.P. Simons and B.G. Davis J. Am. Chem. Soc. 135, 16895-16903, 2013.

Effects of the naturally-occurring contaminant microcystins on the Azolla filiculoides-Anabaena azollae symbiosis.

PubMed

Pereira, A L; Monteiro, B; Azevedo, J; Campos, A; Osório, H; Vasconcelos, V

2015-08-01

Harmful algal blooms (HABs) contaminate aquatic ecosystems and are responsible for animal poisoning worldwide. We conducted a toxicity test with the aquatic fern and the biofertilizer, Azolla filiculoides. The sporophytes were exposed to three concentrations (0.01, 0.1 and 1μgmL(-1)) of a microcystin (MC) cyanobacterial crude extract and purified MC-LR. The growth of A. filiculoides decreased only at 1μgmL(-1) crude extract concentration while with MC-LR it decreased at all the tested concentrations, indicating that the presence of other compounds in the crude extract altered toxicity and stimulated the fern growth at lower concentrations (0.01 and 0.1μgmL(-1)). Both phycoerythrocyanin and allophycocyanin levels decreased in all the concentrations of crude extract and MC-LR. The phycocyanin had a marked increase at 0.1μgmL(-1) crude extract concentration and a marked decrease at 1μgmL(-1) MC-LR concentration. These changes in the phycobiliprotein content indicate a shift in the antenna pigments of the cyanobionts of A. filiculoides. The changes in two oxidative stress enzymes, glutathione reductase for the crude extract assay and glutathione peroxidase for MC-LR assay, points towards the induction of stress defense responses. The low bioconcentration factor in both crude extract and MC-LR treatments can suggest the low uptake of microcystins, and indicates that the aquatic fern can be used as a biofertilizer and as animal feed but is not suitable for MC phytoremediation. Copyright © 2015 Elsevier Inc. All rights reserved.

Are distal radius fracture classifications reproducible? Intra and interobserver agreement.

PubMed

Belloti, João Carlos; Tamaoki, Marcel Jun Sugawara; Franciozi, Carlos Eduardo da Silveira; Santos, João Baptista Gomes dos; Balbachevsky, Daniel; Chap Chap, Eduardo; Albertoni, Walter Manna; Faloppa, Flávio

2008-05-01

Various classification systems have been proposed for fractures of the distal radius, but the reliability of these classifications is seldom addressed. For a fracture classification to be useful, it must provide prognostic significance, interobserver reliability and intraobserver reproducibility. The aim here was to evaluate the intraobserver and interobserver agreement of distal radius fracture classifications. This was a validation study on interobserver and intraobserver reliability. It was developed in the Department of Orthopedics and Traumatology, Universidade Federal de São Paulo - Escola Paulista de Medicina. X-rays from 98 cases of displaced distal radius fracture were evaluated by five observers: one third-year orthopedic resident (R3), one sixth-year undergraduate medical student (UG6), one radiologist physician (XRP), one orthopedic trauma specialist (OT) and one orthopedic hand surgery specialist (OHS). The radiographs were classified on three different occasions (times T1, T2 and T3) using the Universal (Cooney), Arbeitsgemeinschaft für Osteosynthesefragen/Association for the Study of Internal Fixation (AO/ASIF), Frykman and Fernández classifications. The kappa coefficient (kappa) was applied to assess the degree of agreement. Among the three occasions, the highest mean intraobserver k was observed in the Universal classification (0.61), followed by Fernández (0.59), Frykman (0.55) and AO/ASIF (0.49). The interobserver agreement was unsatisfactory in all classifications. The Fernández classification showed the best agreement (0.44) and the worst was the Frykman classification (0.26). The low agreement levels observed in this study suggest that there is still no classification method with high reproducibility.

Interference by weeds and deer with Allegheny hardwood reproduction

Treesearch

Stephen B. Horsley; David A. Marquis

1983-01-01

Deer browsing and interference from forest weeds, particularly hayscented fem (Dennstaedtia punctilobula (Michx.) Moore), New York fern (Thelypteris noveboracensis L.), and short husk grass (Brachyelytrnm erectum Schreb.), influence the establishment of Allegheny hardwood reproduction. We determined the...

Nature Study with the Microscope.

ERIC Educational Resources Information Center

Sollberger, Dwight E.

1991-01-01

Identifies specific instruction difficulties, potential problems, solutions, and activities for successful use of microscopes in the classroom. Procedures are outlined for guiding students in creating their own slides with monocotyledon and dicotyledon stems, fern spores, stomata, lichens, and red onions. (MCO)

Molecular phylogeny of Entomophthoromycota

USDA-ARS?s Scientific Manuscript database

The Entomophthoromycota is a ubiquitous group of fungi best known as pathogens of a wide variety of economically important insect pests, arachnids, and other soil invertebrates, a smaller number of parasites of reptiles, vertebrates (including humans), macromycetes, fern gametophytes, and desmid alg...

Biology Notes.

ERIC Educational Resources Information Center

School Science Review, 1980

1980-01-01

Outlines a variety of laboratory procedures, discussions, and demonstrations including in vitro contraction of muscle fibres and muscle proteins, sucrose density-gradient centrifugation, fern spore development, digestion of starch, construction of a small mammal trap, microscope selection, and occurrence and toxicity of mycotoxins. (GS)

An annotated list of the flora of the Bisley Area Luquillo Experimental Forest, Puerto Rico 1987 to 1992

Treesearch

Jesus Danilo Chinea; Renee J. Beymer; Carlos Rivera; Ines Sastre de Jeses; F.N. Scatena

1993-01-01

Known species of plants, including bryophytes and ferns, are listed for the area of the Bisley experimental watershed area, a subtropical wet forest in the Luquillo Mountains of northeastern Puerto Rico.

Plant Development & the Fern Life Cycle: Using "Ceratopteris richardii."

ERIC Educational Resources Information Center

Renzaglia, Karen S.; And Others

1995-01-01

Presents laboratory activities focusing on the development of sexually mature gametophytes from single-celled spores. Includes techniques for culture and manipulation of gametophyte development from spores that are applicable for hands-on activities for students at all levels. (MKR)

Stellar map of neolithic man

NASA Technical Reports Server (NTRS)

Pskovskiy, Y. P.

1978-01-01

Observations made by ancient man are of great interest to present day astronomers. Drawings made by neolithic man in caves show a surprising sense of perspective. The discoveries in the Fern Grotto in California are of special interest. Photographs of cave drawings are included.

Final Environmental Assessment: Hurlburt Field Skeet & Trap Club

DTIC Science & Technology

2008-07-01

Invasive Species). To date, 18 Category I and 8 Category II species have been documented on Eglin AFB. Chinese tallow, or popcorn tree ( Triadica ... sebifera ), cogon grass (Imperata cylindrical), Japanese climbing fern (Lygodium japonicum), Chinese privet/hedge (Ligustrum sinense), and torpedo grass

7 CFR 340.1 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-01-01

... written permit issued by the Administrator, for the introduction of a regulated article under conditions... mosses, ferns, angiosperms, gymnosperms, and lichens (which contain algae) including any parts (e.g... that all conditions contained in the permit and requirements in this part are complied with. A...

7 CFR 340.1 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-01-01

... written permit issued by the Administrator, for the introduction of a regulated article under conditions... mosses, ferns, angiosperms, gymnosperms, and lichens (which contain algae) including any parts (e.g... that all conditions contained in the permit and requirements in this part are complied with. A...

West Harbor, Ohio Recreational Navigation Improvement. Revision.

DTIC Science & Technology

1979-03-01

small flowering plants such as mallow (Malva sp.) exist throughout this area (see page 123). 2.29 The presence of trees close to the Lake Erie shoreline...occidentalis L. common Houstonia nigricans (Lam.) Fern. common -aprifoliaceae Sambucus canadensis L. common Cucurbitaceae Echinocystis lobata (Michx

Investigation of Listeria, Salmonella, and toxigenic Escherichia coli in various pet foods.

PubMed

Nemser, Sarah M; Doran, Tara; Grabenstein, Michael; McConnell, Terri; McGrath, Timothy; Pamboukian, Ruiqing; Smith, Angele C; Achen, Maya; Danzeisen, Gregory; Kim, Sun; Liu, Yong; Robeson, Sharon; Rosario, Grisel; McWilliams Wilson, Karen; Reimschuessel, Renate

2014-09-01

The Veterinary Laboratory Investigation and Response Network (Vet-LIRN), in collaboration with the Food Emergency Response Network (FERN) and its Microbiology Cooperative Agreement Program (MCAP) laboratories, conducted a study to evaluate the prevalence of selected microbial organisms in various types of pet foods. The goal of this blinded study was to help the Center for Veterinary Medicine prioritize potential future pet food-testing efforts. The study also increased the FERN laboratories' screening capabilities for foodborne pathogens in animal feed matrices, since such pathogens may also be a significant health risk to consumers who come into contact with pet foods. Six U.S. Food and Drug Administration FERN MCAP laboratories analyzed approximately 1056 samples over 2 years. Laboratories tested for Salmonella, Listeria, Escherichia coli O157:H7 enterohemorrhagic E. coli, and Shiga toxin-producing strains of E. coli (STEC). Dry and semimoist dog and cat foods purchased from local stores were tested during Phase 1. Raw dog and cat foods, exotic animal feed, and jerky-type treats purchased through the Internet were tested in Phase 2. Of the 480 dry and semimoist samples, only 2 tested positive: 1 for Salmonella and 1 for Listeria greyii. However, of the 576 samples analyzed during Phase 2, 66 samples were positive for Listeria (32 of those were Listeria monocytogenes) and 15 samples positive for Salmonella. These pathogens were isolated from raw foods and jerky-type treats, not the exotic animal dry feeds. This study showed that raw pet foods may harbor food safety pathogens, such as Listeria monocytogenes and Salmonella. Consumers should handle these products carefully, being mindful of the potential risks to human and animal health.

Stomatal cell wall composition: distinctive structural patterns associated with different phylogenetic groups

PubMed Central

Shtein, Ilana; Shelef, Yaniv; Marom, Ziv; Zelinger, Einat; Schwartz, Amnon; Popper, Zoë A.; Bar-On, Benny

2017-01-01

Background and Aims Stomatal morphology and function have remained largely conserved throughout ∼400 million years of plant evolution. However, plant cell wall composition has evolved and changed. Here stomatal cell wall composition was investigated in different vascular plant groups in attempt to understand their possible effect on stomatal function. Methods A renewed look at stomatal cell walls was attempted utilizing digitalized polar microscopy, confocal microscopy, histology and a numerical finite-elements simulation. The six species of vascular plants chosen for this study cover a broad structural, ecophysiological and evolutionary spectrum: ferns (Asplenium nidus and Platycerium bifurcatum) and angiosperms (Arabidopsis thaliana and Commelina erecta) with kidney-shaped stomata, and grasses (angiosperms, family Poaceae) with dumbbell-shaped stomata (Sorghum bicolor and Triticum aestivum). Key Results Three distinct patterns of cellulose crystallinity in stomatal cell walls were observed: Type I (kidney-shaped stomata, ferns), Type II (kidney-shaped stomata, angiosperms) and Type III (dumbbell-shaped stomata, grasses). The different stomatal cell wall attributes investigated (cellulose crystallinity, pectins, lignin, phenolics) exhibited taxon-specific patterns, with reciprocal substitution of structural elements in the end-walls of kidney-shaped stomata. According to a numerical bio-mechanical model, the end walls of kidney-shaped stomata develop the highest stresses during opening. Conclusions The data presented demonstrate for the first time the existence of distinct spatial patterns of varying cellulose crystallinity in guard cell walls. It is also highly intriguing that in angiosperms crystalline cellulose appears to have replaced lignin that occurs in the stomatal end-walls of ferns serving a similar wall strengthening function. Such taxon-specific spatial patterns of cell wall components could imply different biomechanical functions, which in turn could be a consequence of differences in environmental selection along the course of plant evolution. PMID:28158449

Non-lignified helical cell wall thickenings in root cortical cells of Aspleniaceae (Polypodiales): histology and taxonomical significance

PubMed Central

Leroux, O.; Bagniewska-Zadworna, A.; Rambe, S. K.; Knox, J. P.; Marcus, S. E.; Bellefroid, E.; Stubbe, D.; Chabbert, B.; Habrant, A.; Claeys, M.; Viane, R. L. L.

2011-01-01

Background and Aims Extraxylary helical cell wall thickenings in vascular plants are not well documented, except for those in orchid velamen tissues which have been studied extensively. Reports on their occurrence in ferns exist, but detailed information is missing. The aim of this study is to focus on the broad patterns of structure and composition and to study the taxonomic occurrence of helical cell wall thickenings in the fern family Aspleniaceae. Methods Structural and compositional aspects of roots have been examined by means of light, electron, epifluorescence and laser scanning confocal microscopy. To assess the taxonomical distribution of helical cell wall thickenings a molecular phylogenetic analysis based on rbcL sequences of 64 taxa was performed. Key Results The helical cell wall thickenings of all examined species showed considerable uniformity of design. The pattern consists of helical, regularly bifurcating and anastomosing strands. Compositionally, the cell wall thickenings were found to be rich in homogalacturonan, cellulose, mannan and xyloglucan. Thioacidolysis confirmed our negative phloroglucinol staining tests, demonstrating the absence of lignins in the root cortex. All taxa with helical cell wall thickenings formed a monophyletic group supported by a 100 % bootstrap value and composed of mainly epiphytic species. Conclusions This is the first report of non-lignified pectin-rich secondary cell walls in ferns. Based on our molecular analysis, we reject the hypothesis of parallel evolution of helical cell wall thickenings in Aspleniaceae. Helical cell wall thickenings can mechanically stabilize the cortex tissue, allowing maximal uptake of water and nutrients during rainfall events. In addition, it can also act as a boundary layer increasing the diffusive pathway towards the atmosphere, preventing desiccation of the stele of epiphytic growing species. PMID:21118842

Effects of cultivation conditions on the uptake of arsenite and arsenic chemical species accumulated by Pteris vittata in hydroponics.

PubMed

Hatayama, Masayoshi; Sato, Takahiko; Shinoda, Kozo; Inoue, Chihiro

2011-03-01

The physiological responses of the arsenic-hyperaccumulator, Pteris vittata, such as arsenic uptake and chemical transformation in the fern, have been investigated. However, a few questions remain regarding arsenic treatment in hydroponics. Incubation conditions such as aeration, arsenic concentration, and incubation period might affect those responses of P. vittata in hydroponics. Arsenite uptake was low under anaerobic conditions, as previously reported. However, in an arsenite uptake experiment, phosphorous (P) starvation-dependent uptake of arsenate was observed under aerobic conditions. Time course-dependent analysis of arsenite oxidation showed that arsenite was gradually oxidized to arsenate during incubation. Arsenite oxidation was not observed in any of the control conditions, such as exposure to a nutrient solution or to culture medium only, or with the use of dried root; arsenite oxidation was only observed when live root was used. This result suggests that sufficient aeration allows the rhizosphere system to oxidize arsenite and enables the fern to efficiently take up arsenite as arsenate. X-ray absorption near edge structure (XANES) analyses showed that long-duration exposure to arsenic using a hydroponic system led to the accumulation of arsenate as the dominant species in the root tips, but not in the whole roots, partly because up-regulation of arsenate uptake by P starvation of the fern was caused and retained by long-time incubation. Analysis of concentration-dependent arsenate uptake by P. vittata showed that the uptake switched from a high-affinity transport system to a low-affinity system at high arsenate concentrations, which partially explains the increased arsenate abundance in the whole root. Copyright © 2010 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Proteogenomic Analysis Greatly Expands the Identification of Proteins Related to Reproduction in the Apogamous Fern Dryopteris affinis ssp. affinis.

PubMed

Grossmann, Jonas; Fernández, Helena; Chaubey, Pururawa M; Valdés, Ana E; Gagliardini, Valeria; Cañal, María J; Russo, Giancarlo; Grossniklaus, Ueli

2017-01-01

Performing proteomic studies on non-model organisms with little or no genomic information is still difficult. However, many specific processes and biochemical pathways occur only in species that are poorly characterized at the genomic level. For example, many plants can reproduce both sexually and asexually, the first one allowing the generation of new genotypes and the latter their fixation. Thus, both modes of reproduction are of great agronomic value. However, the molecular basis of asexual reproduction is not well understood in any plant. In ferns, it combines the production of unreduced spores (diplospory) and the formation of sporophytes from somatic cells (apogamy). To set the basis to study these processes, we performed transcriptomics by next-generation sequencing (NGS) and shotgun proteomics by tandem mass spectrometry in the apogamous fern D. affinis ssp. affinis . For protein identification we used the public viridiplantae database (VPDB) to identify orthologous proteins from other plant species and new transcriptomics data to generate a "species-specific transcriptome database" (SSTDB). In total 1,397 protein clusters with 5,865 unique peptide sequences were identified (13 decoy proteins out of 1,410, protFDR 0.93% on protein cluster level). We show that using the SSTDB for protein identification increases the number of identified peptides almost four times compared to using only the publically available VPDB. We identified homologs of proteins involved in reproduction of higher plants, including proteins with a potential role in apogamy. With the increasing availability of genomic data from non-model species, similar proteogenomics approaches will improve the sensitivity in protein identification for species only distantly related to models.

Ressurrection of Curimatus albula Lütken (Characiformes: Curimatidae), a senior synonym of Cyphocharax lundi Dutra, Penido, Mello & Pessali.

PubMed

Dutra, Guilherme Moreira; Penido, Iago DE Souza; Pessali, Tiago Casarim; Netto-Ferreira, Andre Luiz

2017-11-08

Curimatus albula Lütken 1874 was described from the Ribeirão da Mata at Lagoa Santa, a tributary of Rio das Velhas, Rio São Francisco basin. The species validity was questioned by Lütken (1875) himself, who suggested that the species could be a synonym of Curimatus gilbert Quoy & Gaimard, a species described from the Rio Macacu, a coastal river tributary of Guanabara bay, Rio de Janeiro. That synonymy was only formally proposed by Eigenmann (1910), and followed by most subsequent authors (e. g. Nielsen, 1974; Vari, 1992), except for Fowler (1975), who erroneously listed C. albula as the senior synonym of C. gilbert. Vari (1989) posteriorly removed both nominal species from Curimatus Oken (= Curimata Bosch) reallocating them in Cyphocharax Fowler, based on the lack of synapomorphic conditions present in other valid curimatid genera. Vari (1989) considered that those nominal species belonged to a major group within Cyphocharax also including C. grandocule Fernández-Yépez, C. modestus Fernández-Yépez, C. santacatarinae Fernández-Yépez, and C. voga Hensel, based on the presence of a rhomboidal caudal pigmentation and "random body spotting". Later, Vari (1992) included C. grandocule along with C. albula in the synonymy of C. gilbert, and listed several characters allowing further distinction of that species from the remaining species of the group (i.e., number of vertebrae, scales in transverse series, and pigmentation characters). Among the characters involving the pigmentation pattern, Vari (1992) stressed the lack of randomly arranged dark spots on the lateral and dorsolateral surfaces of the body in C. gilbert (versus present in C. voga).

Investigation of Listeria, Salmonella, and Toxigenic Escherichia coli in Various Pet Foods

PubMed Central

Doran, Tara; Grabenstein, Michael; McConnell, Terri; McGrath, Timothy; Pamboukian, Ruiqing; Smith, Angele C.; Achen, Maya; Danzeisen, Gregory; Kim, Sun; Liu, Yong; Robeson, Sharon; Rosario, Grisel; McWilliams Wilson, Karen; Reimschuessel, Renate

2014-01-01

Abstract The Veterinary Laboratory Investigation and Response Network (Vet-LIRN), in collaboration with the Food Emergency Response Network (FERN) and its Microbiology Cooperative Agreement Program (MCAP) laboratories, conducted a study to evaluate the prevalence of selected microbial organisms in various types of pet foods. The goal of this blinded study was to help the Center for Veterinary Medicine prioritize potential future pet food–testing efforts. The study also increased the FERN laboratories' screening capabilities for foodborne pathogens in animal feed matrices, since such pathogens may also be a significant health risk to consumers who come into contact with pet foods. Six U.S. Food and Drug Administration FERN MCAP laboratories analyzed approximately 1056 samples over 2 years. Laboratories tested for Salmonella, Listeria, Escherichia coli O157:H7 enterohemorrhagic E. coli, and Shiga toxin–producing strains of E. coli (STEC). Dry and semimoist dog and cat foods purchased from local stores were tested during Phase 1. Raw dog and cat foods, exotic animal feed, and jerky-type treats purchased through the Internet were tested in Phase 2. Of the 480 dry and semimoist samples, only 2 tested positive: 1 for Salmonella and 1 for Listeria greyii. However, of the 576 samples analyzed during Phase 2, 66 samples were positive for Listeria (32 of those were Listeria monocytogenes) and 15 samples positive for Salmonella. These pathogens were isolated from raw foods and jerky-type treats, not the exotic animal dry feeds. This study showed that raw pet foods may harbor food safety pathogens, such as Listeria monocytogenes and Salmonella. Consumers should handle these products carefully, being mindful of the potential risks to human and animal health. PMID:24824368

Use of cosmogenic 35S for comparing ages of water from three alpine-subalpine basins in the Colorado Front Range

USGS Publications Warehouse

Sueker, J.K.; Turk, J.T.; Michel, R.L.

1999-01-01

High-elevation basins in Colorado are a major source of water for the central and western United States; however, acidic deposition may affect the quality of this water. Water that is retained in a basin for a longer period of time may be less impacted by acidic deposition. Sulfur-35 (35S), a short-lived isotope of sulfur (t( 1/2 ) = 87 days), is useful for studying short-time scale hydrologic processes in basins where biological influences and water/rock interactions are minimal. When sulfate response in a basin is conservative, the age of water may be assumed to be that of the dissolved sulfate in it. Three alpine-subalpine basins on granitic terrain in Colorado were investigated to determine the influence of basin morphology on the residence time of water in the basins. Fern and Spruce Creek basins are glaciated and accumulate deep snowpacks during the winter. These basins have hydrologic and chemical characteristics typical of systems with rapid hydrologic response times. The age of sulfate leaving these basins, determined from the activity of 35S, averages around 200 days. In contrast, Boulder Brook basin has broad, gentle slopes and an extensive cover of surficial debris. Its area above treeline, about one-half of the basin, is blown free of snow during the winter. Variations in flow and solute concentrations in Boulder Brook are quite small compared to Fern and Spruce Creeks. After peak snowmelt, sulfate in Boulder Brook is about 200 days older than sulfate in Fern and Spruce Creeks. This indicates a substantial source of older sulfate (lacking 35S) that is probably provided from water stored in pore spaces of surficial debris in Boulder Brook basin.

Effects of DA-6034 on aqueous tear fluid secretion and conjunctival goblet cell proliferation.

PubMed

Choi, Seul Min; Lee, Yeong Geon; Seo, Mi Jung; Kang, Kyung Koo; Ahn, Byoung Ok; Yoo, Moohi

2009-06-01

This study was conducted to evaluate the effect of DA-6034, a potent secretagogue, on aqueous tear fluid secretion and its quality in normal rabbit. We also evaluated, in animal models of experimentally induced dry eye disease, its effectiveness over time to stimulate aqueous tear production by ocular ferning test and goblet cell proliferation. Aqueous tear production, total protein levels, and glycoprotein levels in normal rabbits were evaluated after topical application of DA-6034 (0.3, 1, and 3%). Moreover, time course aqueous tear volume measurement and ocular ferning test in tear fluid were performed in dry eyes of rabbits that had been given 1% atropine sulfate, topically. Altogether, tear fluid production and conjunctival goblet cell numbers were measured in dry eyes of mice that had been given topical scopolamine. Topical application of DA-6034 (0.3, 1, and 3%) significantly increased (P < 0.05) aqueous tear production in a concentration-dependent manner in normal rabbits. There was no change in total protein levels while glycoprotein levels were significantly increased (P < 0.05) at 3% DA-6034. The increase in aqueous tear fluid was significant (P < 0.05) and lasted for 2 h post-instillation in dry eyes of rabbits that had been given 1% atropine sulfate; 10-day repeated instillation of the drug in this model resulted in large and homogeneous fern-like tear patterns. In a mouse model, DA-6034 given as a 3% eyedrop solution significantly increased (P < 0.05) tear fluid production and conjunctival goblet cell number. These results suggest that DA-6034 accelerates not only tear secretion but also mucin production and may be a potential therapeutic agent for the treatment of dry eye disease.

Cell wall polysaccharides from fern leaves: evidence for a mannan-rich Type III cell wall in Adiantum raddianum.

PubMed

Silva, Giovanna B; Ionashiro, Mari; Carrara, Thalita B; Crivellari, Augusto C; Tiné, Marco A S; Prado, Jefferson; Carpita, Nicholas C; Buckeridge, Marcos S

2011-12-01

Primary cell walls from plants are composites of cellulose tethered by cross-linking glycans and embedded in a matrix of pectins. Cell wall composition varies between plant species, reflecting in some instances the evolutionary distance between them. In this work the monosaccharide compositions of isolated primary cell walls of nine fern species and one lycophyte were characterized and compared with those from Equisetum and an angiosperm dicot. The relatively high abundance of mannose in these plants suggests that mannans may constitute the major cross-linking glycan in the primary walls of pteridophytes and lycophytes. Pectin-related polysaccharides contained mostly rhamnose and uronic acids, indicating the presence of rhamnogalacturonan I highly substituted with galactose and arabinose. Structural and fine-structural analyses of the hemicellulose fraction of leaves of Adiantum raddianum confirmed this hypothesis. Linkage analysis showed that the mannan contains mostly 4-Man with very little 4,6-Man, indicating a low percentage of branching with galactose. Treatment of the mannan-rich fractions with endo-β-mannanase produced characteristic mannan oligosaccharides. Minor amounts of xyloglucan and xylans were also detected. These data and those of others suggest that all vascular plants contain xyloglucans, arabinoxylans, and (gluco)mannans, but in different proportions that define cell wall types. Whereas xyloglucan and pectin-rich walls define Type I walls of dicots and many monocots, arabinoxylans and lower proportion of pectin define the Type II walls of commelinoid monocots. The mannan-rich primary walls with low pectins of many ferns and a lycopod indicate a fundamentally different wall type among land plants, the Type III wall. Copyright © 2011 Elsevier Ltd. All rights reserved.

Arborescent vascular dilatation mimicking Lichtenberg figures from lightning.

PubMed

Tempark, Therdpong; Iwasaki, Julie; Shwayder, Tor

2014-01-01

The clinical presentation of arborizing vascular dilatation can resemble Lichtenberg figures from lightning. Both have a feather-like or ferning pattern. We report an interesting case of pressure-induced vasodilatation (PIV) caused by temporary vascular occlusion from jeans buttons. © 2014 Wiley Periodicals, Inc.

Solar energy system performance evaluation: Seasonal report for Fern Lansing, Lansing, Michigan

NASA Technical Reports Server (NTRS)

1980-01-01

A solar space heating and hot water system's operational performance from April 1979 through March 1980 is evaluated. Solar energy satisfied 15 percent of the total measured load (hot water plus space heating). Net savings were approximately 21 million BTUs.

Lycopodium: Careful Harvest Fact Sheet

Treesearch

Elizabeth Nauertz

2003-01-01

Lycopodium comes from the Greek words "luko" (wolf) and "podos" (foot); thus the common name of "wolf's paw" or "Wolf's foot." Despite the common names of clubmoss, Lycopodium species are not related to mosses, but rather to ferns. They are evergreen, perennial, clonal, and rhizomatous in nature.

Characterization of 12 polymorphic microsatellite loci of Pityopsis graminifolia var. latifolia

USDA-ARS?s Scientific Manuscript database

Pityopsis graminifolia (Michx.) Small var. latifolia (Fern.) Semple is an herbaceous perennial that grows in close proximity to the federally endangered species P. ruthii (Small) Small. Twelve polymorphic microsatellite loci were identified from 87 samples of P. graminifolia var. latifolia and addit...

76 FR 45649 - Notice of Final Federal Agency Actions on I-5: Fern Valley Interchange Project: Jackson County, OR

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-29

.... 2000(d) et seq.]; American Indian Religious Freedom Act [42 U.S.C. 1996]; Farmland Protection Policy.... 13007 Indian Sacred Sites, E.O. 13287 Preserve America; E.O. 13175 Consultation and Coordination with...

EVOLUTIONARY SIGNIFICANCE OF ISOPRENE EMISSION FROM MOSSES

EPA Science Inventory

Isoprene emission has been documented and characterized from species in all major groups of vascular plants. We report in our survey that isoprene emission is much more common in mosses and ferns than later divergent land plants but is absent in liverworts and hornworts. The li...

Spatial distribution, temporal variation and specificity of microhabitat of Tropisternus species (Coleoptera: Hydrophilidae) in permanent ponds.

PubMed

Gómez Lutz, M C; Kehr, A I; Fernández, L A

2015-06-01

The spatial distribution and temporal variation of 11 species of Tropisternus were analyzed in two permanent ponds located in the province of Corrientes, Argentina. Samples were collected every 15 days, between October 2010 and March 2011. The species recorded were Tropisternus collaris (Fabricius), Tropisternus ovalis Castelnau, Tropisternus laevis (Sturm), Tropisternus lateralis limbatus (Brullé), Tropisternus longispina Fernández & Bachmann, Tropisternus carinispina Orchymont, Tropisternus bourmeisteri Fernández & Bachmann, Tropisternus apicipalpis (Chevrolat), Tropisternus dilatatus Bruch, Tropisternus obesus Bruch, and Tropisternus ignoratus Knisch. The first four were present in higher proportions than the remaining during most of the study period. The spatial distribution of individuals was mostly related to the homogeneity or heterogeneity of the ecosystem in relation to microhabitats with aquatic vegetation: In ponds with different microhabitats, individuals were mainly aggregated, whereas in ponds with homogenous features, individuals were randomly distributed. However, when species were analyzed individually, the spatial distribution and the use of microhabitat by each species were different with respect to preference and behavior.

Bovine papillomavirus type 2 infects the urinary bladder of water buffalo (Bubalus bubalis) and plays a crucial role in bubaline urothelial carcinogenesis.

PubMed

Roperto, Sante; Russo, Valeria; Ozkul, Ayhan; Sepici-Dincel, Aylin; Maiolino, Paola; Borzacchiello, Giuseppe; Marcus, Ioan; Esposito, Iolanda; Riccardi, Marita Georgia; Roperto, Franco

2013-02-01

Bovine papillomavirus type 2 (BPV-2) has been shown to infect and play a role in urinary bladder carcinogenesis of buffaloes grazed on pastures with ferns from the Marmara and Black Sea Regions of Turkey. BPV-2 DNA has been found in both neoplastic and non-neoplastic lesions of the urinary bladder. Furthermore, this virus may be a normal inhabitant of the urinary bladder since BPV-2 DNA has also been detected in clinically normal buffaloes. The viral activation by fern immunosuppressant or carcinogen may trigger the urothelial cell transformation. The E5 oncoprotein was solely detected in urothelial tumours and appeared to be co-localized with the overexpressed and phosphorylated platelet derived growth factor (PDGF) β receptor in a double-colour immunofluorescence assay. Our results indicate that the E5-PDGF β receptor interaction also occurs in spontaneous tumours of the bubaline urinary bladder, revealing an additional role of BPV-2 in bladder carcinogenesis of buffaloes.

Flora of the Mayacmas Mountains. [Listing of 679 species in the Geysers Geothermal Resource area

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

Neilson, J.A.

1981-09-01

This flora describes the plants that occur within the Mayacmas Mountain Range of northern California. It is the result of ten years of environmental assessment by the author in the Geysers Geothermal Resource area, located in the center of the Mayacmas Range. The flora includes notes on plant communities and ecology of the area, as well as habitat and collection data for most of the 679 species covered. Altogether 74 families, 299 genera and 679 species are included in the flora. The work is divided into eight subdivisions: trees; shrubs; ferns and fern allies; aquatic plants; tules, sedges, and rushes;more » lilies and related plants; dicot herbs; and grasses. Within each subdivision, family, genera and species are listed alphabetically. Keys are provided at the beginning of each subdivision. A unique combination of physical, environmental and geologic factors have resulted in a rich and diverse flora in the Mayacmas. Maps have been provided indicating known locations for species of rare or limited occurrence.« less

Arundina graminifolia var. revoluta (Arethuseae, Orchidaceae) has fern-type rheophyte characteristics in the leaves.

PubMed

Yorifuji, Eri; Ishikawa, Naoko; Okada, Hiroshi; Tsukaya, Hirokazu

2015-03-01

Morphological and molecular variation between Arundina graminifolia var. graminifolia and the dwarf variety, A. graminifolia var. revoluta, was examined to assess the validity of their taxonomic characteristics and genetic background for identification. Morphological analysis in combination with field observations indicated that A. graminifolia var. revoluta is a rheophyte form of A. graminifolia characterized by narrow leaves, whereas the other morphological characteristics described for A. graminifolia var. revoluta, such as smaller flowers and short stems, were not always accompanied by the narrower leaf phenotype. Molecular analysis based on matK sequences indicated that only partial differentiation has occurred between A. graminifolia var. graminifolia and A. graminifolia var. revoluta. Therefore, we should consider the rheophyte form an ecotype rather than a variety. Anatomical observations of the leaves revealed that the rheophyte form of A. graminifolia possessed characteristics of the rheophytes of both ferns and angiosperms, such as narrower palisade tissue cells and thinner spongy tissue cells, as well as fewer cells in the leaf-width direction and fewer mesophyll cell layers.

Dissociated roles of the anterior cingulate cortex in reward and conflict processing as revealed by the feedback error-related negativity and N200.

PubMed

Baker, Travis E; Holroyd, Clay B

2011-04-01

The reinforcement learning theory of the error-related negativity (ERN) holds that the impact of reward signals carried by the midbrain dopamine system modulates activity of the anterior cingulate cortex (ACC), alternatively disinhibiting and inhibiting the ACC following unpredicted error and reward events, respectively. According to a recent formulation of the theory, activity that is intrinsic to the ACC produces a component of the event-related brain potential (ERP) called the N200, and following unpredicted rewards, the N200 is suppressed by extrinsically applied positive dopamine reward signals, resulting in an ERP component called the feedback-ERN (fERN). Here we demonstrate that, despite extensive spatial and temporal overlap between the two ERP components, the functional processes indexed by the N200 (conflict) and the fERN (reward) are dissociable. These results point toward avenues for future investigation. Copyright © 2011 Elsevier B.V. All rights reserved.

Doubling the estimate of invertebrate biomass in a rainforest canopy.

PubMed

Ellwood, Martin D F; Foster, William A

2004-06-03

Forest canopies represent the functional interface between 90% of the Earth's terrestrial biomass and the atmosphere and include some of the most threatened of all terrestrial ecosystems. However, we lack even a basic understanding of how the biomass of plants and animals is distributed throughout forest canopies, even though this information is vital for estimating energy flow, carbon cycling, resource use and the transfer of materials within this ecosystem. Here we measure the biomass of invertebrates living in a common rainforest epiphyte, describe a striking relationship between fern size and the biomass of animals within the ferns, and reveal that one large epiphyte may contain an invertebrate biomass similar to that found in the whole of the rest of the tree crown on which it is growing. Using these data, we show that including the fauna of these epiphytes--a neglected component in rainforest ecosystems--can more than double our estimate of the total invertebrate biomass in an entire rainforest canopy.

The suitability of select ferns as hosts for Archips machlopis (Lepidoptera: Tortricidae)

USDA-ARS?s Scientific Manuscript database

Surveys for natural enemies of invasive weed Lygodium microphyllum in Thailand resulted in the collection of lepidopteran Archips machlopis. Multiple generations of the tortricid were reared on L. microphyllum in a quarantine laboratory, demonstrating that the plant is a developmental host. Further ...

Evolutionary history of two endemic Appalachian conifers revealed using microsatellite markers

Treesearch

Kevin M. Potter; John Frampton; Sedley A. Josserand; C. Dana Nelson

2010-01-01

Fraser fir (Abies fraseri [Pursh] Poir.) and intermediate fir (Abies balsamea [L.] Mill. var. phanerolepis Fern.) exist in small populations in the Appalachian highlands of the southeastern United States. We used ten nuclear microsatellite markers to quantify genetic variation within Fraser fir and intermediate...

Scalable geocomputation: evolving an environmental model building platform from single-core to supercomputers

NASA Astrophysics Data System (ADS)

Schmitz, Oliver; de Jong, Kor; Karssenberg, Derek

2017-04-01

There is an increasing demand to run environmental models on a big scale: simulations over large areas at high resolution. The heterogeneity of available computing hardware such as multi-core CPUs, GPUs or supercomputer potentially provides significant computing power to fulfil this demand. However, this requires detailed knowledge of the underlying hardware, parallel algorithm design and the implementation thereof in an efficient system programming language. Domain scientists such as hydrologists or ecologists often lack this specific software engineering knowledge, their emphasis is (and should be) on exploratory building and analysis of simulation models. As a result, models constructed by domain specialists mostly do not take full advantage of the available hardware. A promising solution is to separate the model building activity from software engineering by offering domain specialists a model building framework with pre-programmed building blocks that they combine to construct a model. The model building framework, consequently, needs to have built-in capabilities to make full usage of the available hardware. Developing such a framework providing understandable code for domain scientists and being runtime efficient at the same time poses several challenges on developers of such a framework. For example, optimisations can be performed on individual operations or the whole model, or tasks need to be generated for a well-balanced execution without explicitly knowing the complexity of the domain problem provided by the modeller. Ideally, a modelling framework supports the optimal use of available hardware whichsoever combination of model building blocks scientists use. We demonstrate our ongoing work on developing parallel algorithms for spatio-temporal modelling and demonstrate 1) PCRaster, an environmental software framework (http://www.pcraster.eu) providing spatio-temporal model building blocks and 2) parallelisation of about 50 of these building blocks using the new Fern library (https://github.com/geoneric/fern/), an independent generic raster processing library. Fern is a highly generic software library and its algorithms can be configured according to the configuration of a modelling framework. With manageable programming effort (e.g. matching data types between programming and domain language) we created a binding between Fern and PCRaster. The resulting PCRaster Python multicore module can be used to execute existing PCRaster models without having to make any changes to the model code. We show initial results on synthetic and geoscientific models indicating significant runtime improvements provided by parallel local and focal operations. We further outline challenges in improving remaining algorithms such as flow operations over digital elevation maps and further potential improvements like enhancing disk I/O.

Identity and origins of introduced and native Azolla species in Florida.

USDA-ARS?s Scientific Manuscript database

Azolla pinnata, an introduced aquatic fern, is spreading rapidly causing concern that it may displace native Azolla. It is now present in the Arthur R. Marshall Loxahatchee National Wildlife Refuge, the northernmost portion of the Florida Everglades. Because A. pinnata subspecies are native to Afri...

Argentina: Background and U.S. Relations

DTIC Science & Technology

2008-11-05

Comercio Internacional, Y Culto, Comunicado de la Cancillería Argentina, September 11, 2008. 43 A. Rebossio, "Fernández Acusa al FBI de Desestablizar...Argentina," El País (Madrid), September 13, 2008. 44 “Argentina Slams Witness in Cash Suitcase Scandal,” Associated Press Newswires, November 4, 2008

7 CFR 319.37-8 - Growing media.

Code of Federal Regulations, 2010 CFR

2010-01-01

... plants) established solely on tree fern slabs, coconut husks, coconut fiber, new clay pots, or new wooden...) Approved growing media are baked expanded clay pellets, coal cinder, coir, cork, glass wool, organic and... this section; (ii) Grown solely in a greenhouse in which sanitary procedures adequate to exclude plant...

Research into Distance Education = Fernlehre und Fernlehrforschung.

ERIC Educational Resources Information Center

Holmberg, Borje, Ed.; Ortner, Gerhard E., Ed.

The papers (from a symposium held at the Fern Universitat) included in this collection focus on distance education in theory and practice. Contributions are written in English or in German, with summaries available for each in the language not used for the paper concerned. Contributions are: (1) "Distance Education as Communication: The…

Feature Modeling in Underwater Environments Using Sparse Linear Combinations

DTIC Science & Technology

2010-01-01

nose of the tor- pedo obviously has a different optical depth than the tail and points in between. Our chosen PSF does not consider this, but it...IEEE Transactions on Information Theory, 52(4), 2006. 4 [6] R. Hess and A. Fern. Improved video registration using non-distinctive local image

Invasive species compendium: Salvinia molesta D.S. Mitchell

USDA-ARS?s Scientific Manuscript database

Salvinia molesta D.S. Mitchell is an invasive aquatic fern native to a small area of south-eastern Brazil. It has spread throughout the world, forming thick mats of vegetation that decrease dissolved oxygen and pH while outcompeting native vegetation. It has been introduced and established into many...

Actualizing Concepts in Home Management: Proceedings of a National Conference.

ERIC Educational Resources Information Center

American Home Economics Association, Washington, DC.

The booklet prints the following papers delivered at a national conference: Actualizing Concepts in Home Management: Decision Making, Dorothy Z. Price; Innovations in Teaching: Ergonomics, Fern E. Hunt; Relevant Concepts of Home Management: Innovations in Teaching, Kay P. Edwards; Standards in a Managerial Context, Florence S. Walker; Organizing:…

Plants and people

Treesearch

Kathryn Lynch

2012-01-01

Salal! Salmonberries! Sword ferns! The Northwest is home to a great number of native plant species that humans have used for centuries. Sadly, many local children are unaware of the history and culture connecting people and plants. Yet, from the beginning of time, plants have provided us food, medicine, and material for clothing, shelter, transportation, decoration,...

29 CFR 788.18 - Preparing other forestry products.

Code of Federal Regulations, 2014 CFR

2014-07-01

... used in the exemption, other forestry products means plants of the forest and the natural properties or substances of such plants and trees. Included among these are decorative greens such as holly, ferns, roots, stems, leaves, Spanish moss, wild fruit, and brush. Christmas trees are only included where they are...

29 CFR 788.18 - Preparing other forestry products.

Code of Federal Regulations, 2013 CFR

2013-07-01

... used in the exemption, other forestry products means plants of the forest and the natural properties or substances of such plants and trees. Included among these are decorative greens such as holly, ferns, roots, stems, leaves, Spanish moss, wild fruit, and brush. Christmas trees are only included where they are...

29 CFR 788.18 - Preparing other forestry products.

Code of Federal Regulations, 2012 CFR

2012-07-01

... used in the exemption, other forestry products means plants of the forest and the natural properties or substances of such plants and trees. Included among these are decorative greens such as holly, ferns, roots, stems, leaves, Spanish moss, wild fruit, and brush. Christmas trees are only included where they are...

29 CFR 788.18 - Preparing other forestry products.

Code of Federal Regulations, 2011 CFR

2011-07-01

... used in the exemption, other forestry products means plants of the forest and the natural properties or substances of such plants and trees. Included among these are decorative greens such as holly, ferns, roots, stems, leaves, Spanish moss, wild fruit, and brush. Christmas trees are only included where they are...

A Guide to Bottomland Hardwood Restoration

DTIC Science & Technology

2001-06-01

Lespedeza cuneata Chinese tallow Triadica sebiferum Cocklebur Xanthium spp. Coffeeweed Sesbania macrocarpa Cogongrass Imperata cylindrica Common...fennel (see small dogfennel) Eupatorium capillifolium Falsenettle (see small-spike falsenettle) Boehmeria cylindrica Fern, various species Osmunda spp...spike falsenettle (see falsenettle) Boehmeria cylindrica Smartweed Polygonum spp. Southern carpetgrass (see common carpetgrass) Axonopus affinis

Risk-rating Saratoga Spittlebug Damage by Abundance of Alternate-host Plants

Treesearch

Louis F. Wilson

1971-01-01

The potential damage of the Saratoga spittlebug to red pine can be predicted by comparing the percentage of ground occupied by sweet-fern with the percentage of ground cover occupied by other nymphal host plants. A risk-rating graph is used to estimate potential damage.

From Content to Practice: Sharing Educational Practice in Edu-Sharing

ERIC Educational Resources Information Center

Klebl, Michael; Kramer, Bernd J.; Zobel, Annett

2010-01-01

For technology-enhanced learning, the idea of "learning objects" transfers the technologies of content management, methods of software engineering and principles of open access to educational resources. This paper reports on CampusContent, a research project and competence centre for e-learning at FernUniversitat in Hagen that designed…

25 CFR 309.12 - What are examples of basketry that are Indian products?

Code of Federal Regulations, 2011 CFR

2011-04-01

..., spruce root, rye grass, sweet grass, yucca, bear grass, beach grass, rabbit brush, fiber, maidenhair fern..., pine needle/raffia effigy baskets, oak splint and braided sweet grass fancy baskets, birchbark containers, baleen baskets, rye grass dance fans, brown ash strawberry baskets, sumac wedding baskets, cedar...

25 CFR 309.12 - What are examples of basketry that are Indian products?

Code of Federal Regulations, 2010 CFR

2010-04-01

..., spruce root, rye grass, sweet grass, yucca, bear grass, beach grass, rabbit brush, fiber, maidenhair fern..., pine needle/raffia effigy baskets, oak splint and braided sweet grass fancy baskets, birchbark containers, baleen baskets, rye grass dance fans, brown ash strawberry baskets, sumac wedding baskets, cedar...

Lower Permian stems as fluvial paleocurrent indicators of the Parnaíba Basin, northern Brazil

NASA Astrophysics Data System (ADS)

Capretz, Robson Louiz; Rohn, Rosemarie

2013-08-01

A comprehensive biostratinomic study was carried out with abundant stems from the Lower Permian Motuca Formation of the intracratonic Parnaíba Basin, central-north Brazil. The fossils represent a rare tropical to subtropical paleofloristic record in north Gondwana. Tree ferns dominate the assemblages (mainly Tietea, secondarily Psaronius), followed by gymnosperms, sphenophytes, other ferns and rare lycophytes. They are silica-permineralized, commonly reach 4 m length (exceptionally more than 10 m), lie loosely on the ground or are embedded in the original sandstone or siltstone matrix, and attract particular attention because of their frequent parallel attitudes. Many tree fern stems present the original straight cylindrical to slightly conical forms, other are somewhat flattened, and the gymnosperm stems are usually more irregular. Measurements of stem orientations and dimensions were made in three sites approximately aligned in a W-E direction in a distance of 27.3 km at the conservation unit "Tocantins Fossil Trees Natural Monument". In the eastern site, rose diagrams for 54 stems indicate a relatively narrow azimuthal range to SE. These stems commonly present attached basal bulbous root mantles and thin cylindrical sandstone envelopes, which sometimes hold, almost adjacent to the lateral stem surface, permineralized fern pinnae and other small plant fragments. In the more central site, 82 measured stems are preferentially oriented in the SW-NE direction, the proportion of gymnosperms is higher and cross-stratification sets of sandstones indicate paleocurrents mainly to NE and secondarily to SE. In the western site, most of the 42 measured stems lie in E-W positions. The predominantly sandy succession, where the fossil stems are best represented, evidences a braided fluvial system under semiarid conditions. The low plant diversity, some xeromorphic features and the supposedly almost syndepositional silica impregnation of the plants are coherent with marked dry seasons. Thick mudstones and some coquinites below and above the sandy interval may represent lacustrine facies formed in probably more humid conditions. The taphonomic history of the preserved plants began with exceptional storms that caused fast-flowing high water in channels and far into the floodplains. In the eastern site region, many tree ferns only fell, thus sometimes covering and protecting plant litter and leaves from further fragmentation. Assemblages of the central and western sites suggest that the trees were uprooted and transported in suspension (floating) parallel to the flow. Heavier ends of stems (according to their form or because of attached basal bulbous root mantle or large apical fronds) were oriented to upstream because of inertial forces. During falling water stage, the stems were stranded on riverbanks, usually maintaining the previous transport orientation, and were slightly buried. The perpendicular or oblique positions of some stems may have been caused by interference with other stems or shallow bars. Rare observed stems were apparently waterlogged before the final depositional process and transported as bedload. The differences of interpreted channel orientations between the three sites are expected in a braided fluvial system, considering the very low gradients of the basin and the work scale in the order of tens of kilometers. The mean direction of the drainage probably was to east and the flows apparently became weaker downstream. This study seems to provide reliable data for paleocurrent interpretations, especially considering areas with scarce preserved sedimentary structures.

Research observation: Hydrolyzable and condensed tannins in plants of northwest Spain forests

USGS Publications Warehouse

Gonzalez-Hernandez, M. P.; Karchesy, J.; Starkey, E.E.

2003-01-01

Tannins are secondary metabolites that may influence feeding by mammals on plants. We analyzed hydrolyzable and condensed tannins in 30 plant species consumed by livestock and deer, as a preliminary attempt to study their possible implications on browsing and grazing in forest ecosystems. Heathers (Ericaceae) and plants of the Rose (Rosaceae) family had tannins, while forbs, grasses and shrubs other than the heathers did not show astringency properties. We found the highest tannin content of all the species in Rubus sp., with the highest value around 180 mg TAE/g dry weight in spring. Potentilla erecta, Alnus glutinosa and Quercus robur were next with 57 to 44 mg TAE/g dw. Total tannins in heathers ranged from 22 to 36 mg TAE/g dw. Levels of condensed tannins were higher than hydrolyzable for most of the species. Only Betula alba, Calluna vulgaris, Pteridium aquilinum and Vaccinium myrtillus had 100% hydrolyzable tannins. Tannin content of the species changed seasonally with highest values during the growing season, corresponding to late winter or early spring, depending on the species.

Research observation: Hydrolyzable and condensed tannins in plants of the northwest

USGS Publications Warehouse

Gonzalez-Hernandez, M. P.; Karchesy, J.; Starkey, Edward E.

2003-01-01

Tannins are secondary metabolites that may influence feeding by mammals on plants. We analyzed hydrolyzable and condensed tannins in 30 plant species consumed by livestock and deer, as a preliminary attempt to study their possible implications on browsing and grazing in forest ecosystems. Heathers (Ericaceae) and plants of the Rose (Rosaceae) family had tannins, while forbs, grasses and shrubs other than the heathers did not show astringency properties. We found the highest tannin content of all the species in Rubus sp., with the highest value around 180 mg TAE/g dry weight in spring. Potentilla erecta, Alnus glutinosa and Quercus robur were next with 57 to 44 mg TAE/g dw. Total tannins in heathers ranged from 22 to 36 mg TAE/g dw. Levels of condensed tannins were higher than hydrolyzable for most of the species. Only Betula alba, Calluna vulgaris, Pteridium aquilinum and Vaccinium myrtillus had 100% hydrolyzable tannins. Tannin content of the species changed seasonally with highest values during the growing season, corresponding to late winter or early spring, depending on the species.

75 FR 52957 - Supplemental Funding Under the Food and Drug Administration's Food Emergency Response Laboratory...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-30

... enhance the lab capabilities to handle human pathogenic bacteria in animal feed. DATES: Important dates... supplemental grant funds will enable analyses of human pathogenic bacteria found in animal feed, for samples... bacteria in animal feed. This additional program will be compatible with other FERN Cooperative Agreement...

Finding of No Significant Impact: Wildland Fire Management Plan at New Boston Air Force Station, New Hampshire

DTIC Science & Technology

2004-01-12

Juncus spp.), Virginia chain fern (Woodwardia virginica), pitcher plant ( Sarracenia purpurea ), meadowsweet (Spirea alba), boneset (Eupatorium perfoliatum... purpurea – – S2 1 Orange-spotted idia Idia diminuendis – – S2/S4 1 Butterflies and Skippers Appalachian brown Satyrodes appalachia – – S1

Forrest or Field?

ERIC Educational Resources Information Center

Mangiante, Elaine Silva

2009-01-01

An open field--with its wildflowers, grasses, and vole tunnels--became an instant classroom. Students' senses were awakened there, and upon entering a nearby forest, they immediately detected a difference: less light and cooler air. "Why are there no grasses in the forest? Why aren't there ferns in the field?" These and other questions emerged as…

29 CFR 788.10 - “Preparing * * * other forestry products.”

Code of Federal Regulations, 2012 CFR

2012-07-01

... products.” As used in the exemption, “other forestry products” mean plants of the forest and the natural properties or substances of such plants and trees. Included among these are decorative greens such as holly, ferns and Christmas trees, roots, stems, leaves, Spanish moss, wild fruit, and brush. Gathering and...

29 CFR 788.10 - “Preparing * * * other forestry products.”

Code of Federal Regulations, 2013 CFR

2013-07-01

... products.” As used in the exemption, “other forestry products” mean plants of the forest and the natural properties or substances of such plants and trees. Included among these are decorative greens such as holly, ferns and Christmas trees, roots, stems, leaves, Spanish moss, wild fruit, and brush. Gathering and...

29 CFR 788.10 - “Preparing * * * other forestry products.”

Code of Federal Regulations, 2011 CFR

2011-07-01

... products.” As used in the exemption, “other forestry products” mean plants of the forest and the natural properties or substances of such plants and trees. Included among these are decorative greens such as holly, ferns and Christmas trees, roots, stems, leaves, Spanish moss, wild fruit, and brush. Gathering and...

29 CFR 788.10 - “Preparing * * * other forestry products.”

Code of Federal Regulations, 2014 CFR

2014-07-01

... products.” As used in the exemption, “other forestry products” mean plants of the forest and the natural properties or substances of such plants and trees. Included among these are decorative greens such as holly, ferns and Christmas trees, roots, stems, leaves, Spanish moss, wild fruit, and brush. Gathering and...

Health Instruction Packages: Nursing--Specific Diseases and Disorders.

ERIC Educational Resources Information Center

Curran, Fern A.; And Others

Text, illustrations, and exercises are utilized in this set of learning modules to instruct nurses and other health care professionals in the symptoms and treatment of common medical disorders. The first module, by Fern A. Curran, discusses the causes of decubitus ulcers (i.e., bedsores), the physical damage they can do, and methods of preventing…

Another new Lygodium-boring species of the musotimine genus Siamusotima (Lepidoptera: Crambidae) from China

USDA-ARS?s Scientific Manuscript database

Siamusotima disrupta Solis, n. sp., is a stem-boring musotimine from China. It was discovered in the stems of several Lygodium Sw. species (Lygodiaceae) during exploration for biological control agents of Lygodium microphyllum (Cav.) R. Br., the Old World climbing fern. This is the second report of ...