WorldWideScience

Sample records for bracken fern pteridium

  1. Role of bracken fern (Pteridium aquilinum (L. Kuhn in animal and human heath/ Toxicidade da samambaia (Pteridium aquilinum (L. Kuhn para a saúde animal e humana

    Directory of Open Access Journals (Sweden)

    Ana Paula F. R. L. Bracarense

    2004-05-01

    Full Text Available The article reviews some of the main characteristics of Pteridium aquilinum (bracken fern and the main consequences of its ingestion by livestock animals, laboratory animals and man. Ptaquiloside is considered the main responsible for the neoplasias in these cases. Three main routes may lead to human exposure to the toxic effects of bracken fern: eating the plant, physical contact (inhalation of the spores or ingestion of contaminated water and ingestion of raw milk from affected animals.O artigo revisa algumas das principais características da planta Pteridium aquilinum (samambaia bem como as conseqüências da sua ingestão por animais de produção, animais de laboratório e pelo próprio homem. O composto ptaquilosídeo encontrado na planta é considerado atualmente o principal responsável pelo aparecimento de neoplasias. No homem, existem três maneiras pelo qual este pode ser intoxicado: ingestão da planta, contato físico (inalação dos esporos ou ingestão de água contaminada e ingestão de leite cru de animais que ingeriram a planta.

  2. Intoxicação experimental aguda por samambaia (Pteridium aquilinum em bovinos Experimental acute poisoning by bracken fern (Pteridium aquilinum in cattle

    Directory of Open Access Journals (Sweden)

    Bruno L. Anjos

    2009-09-01

    conflitantes, não permitindo concluir se a coagulação intravascular disseminada tem participação na patogênese das hemorragias nessa intoxicação. A citopatologia e histopatologia da medula óssea dos quatro bovinos intoxicados revelaram acentuada diminuição no número de células hematopoéticas das três linhagens medulares, caracterizando insuficiência medular por aplasia; conclui-se que apenas eventos da hemostasia primária devidos a trombocitopenia são responsáveis pelas hemorragias. Na hemocultura de três dos bovinos intoxicados houve crescimento de Klebsiella oxytoca, Staphylococcus hyicus e Staphylococcus aureus, indicando que a septicemia, facilitada pela neutropenia, pode ter participação na causa da morte de bovinos na intoxicação aguda pela ingestão de P. aquilinum. Aspectos adicionais de interesse na reprodução da intoxicação aguda por samambaia em bovinos deste relato incluem o desenvolvimento de hematúria na doença aguda e a apresentação da chamada forma laríngea da doença.This experiment was design to address the following points in relation to the acute poisoning by bracken fern (Pteridium aquilinum in cattle: 1 the severity of the thrombocytopenia in different stages of the intoxication and its relationship to possible deficits in the secondary hemostasis, 2 the relationship between neutropenia and the morphological signs of septicemia occasionally found at necropsy, and 3 the mechanism of anemia and its relationship with blood loss, medium life of erythrocytes and the progress of the disease. The fresh green upper parts of P. aquilinum were fed to four mixed breed calves with average age of 18 months and weights ranging from 190 to 215 kg. A calf of similar age and weight was kept together with the other four under the same conditions, except for the ingestion of P. aquilinum. The four fern-fed calves died with typical features of acute bracken fern poisoning after being fed with the plant for 53-58 days daily doses of 8.0, 8

  3. The role of bracken (Pteridium aquilinum) in forest dynamics = [De rol van adelaarsvaren (Pteridium aquilinum) in de bosdynamiek

    NARCIS (Netherlands)

    Ouden, den J.

    2000-01-01

    Bracken fern ( Pteridium aquilinum ) causes stagnation in forest succession in many parts of the world. The mechanisms by which bracken affects the establishment and growth of plant species are studied, focusing on the regeneration of tree species in forest

  4. Neoplasias do trato alimentar superior de bovinos associadas ao consumo espontâneo de samambaia (Pteridium aquilinum Neoplasms of the upper digestive tract of cattle associated with spontaneous ingestion of bracken fern (Pteridium aquilinum

    Directory of Open Access Journals (Sweden)

    Marione A. Moreira Souto

    2006-06-01

    /orofaringe, epiglote, média (terços cranial, médio e caudal do esôfago e caudal (entrada do rúmen e rúmen do TAS, observou-se que a localização era cranial em 39% dos casos, média em 16%, e caudal em 45%. Utilizando-se esse mesmo critério de agrupamento, porém considerando o número total de vezes em que CCEs (de tamanhos variados foram diagnosticados nas regiões cranial, média e caudal, os números alteraram-se para 34, 26 e 40%, respectivamente. As evidências epidemiológicas e histomorfológicas relatadas neste estudo reforçam as observações de uma estreita correlação entre a infecção pelo papiloma-vírus bovino tipo 4, causador da papilomatose digestiva, e a co-carcinogênese química dos princípios tóxicos da samambaia na patogênese dos CCEs do TAS de bovinos. Entretanto, a presença de alterações pré-neoplásicas (áreas de displasia, áreas de CCE in situ ou CCEs em estágios iniciais de desenvolvimento, independentemente da presença de papilomas no local, mostram claramente ser possível o desenvolvimento de CCEs diretamente do epitélio normal, possivelmente por uma ação direta dos carcinó-genos químicos da samambaia.Thirty bovine with neoplasms of the upper digestive tract (UDT associated with spontaneous ingestion of bracken fern (Pteridium aquilinum were studied. They were from 27 farms, located in the municipalities of Jaguari (23 and Nova Esperança do Sul (4, Rio Grande do Sul, Brazil. The total cattle population in those farms was 1,090 and large amounts of bracken fern were found in the pastures. Twenty-six of the affected cattle were cows and four were castrated males, 3-13 years of age; most of them were 7-8 years old (46,6%. Clinical signs observed in the affected animals were progressive weight loss, absence of ruminal movements, cough, dysphagia, regurgitation, halitosis, diarrhea, and bloat. Less frequent signs were selective appetite, dyspnea, and salivation. Two bovine died and 28 were submitted to euthanasia in advanced stage

  5. Environmental Fate and Analysis of Ptaquiloside from the Bracken Fern

    DEFF Research Database (Denmark)

    Clauson-Kaas, Frederik

    The naturally occurring phytotoxin ptaquiloside (PTA) has long been known to be both acute toxic and carcinogenic. Contents of more than 1% ptaquiloside on dry weight has been detected in bracken (Pteridium spp.), a fern distributed across the globe in often dense populations. This work focused...... on the fate of PTA in the soil-water system, from where it may leach to drinking water sources. PTA was detected in concentrations up to 2.2 µg/L in natural waters receiving drainage from bracken populations, and was found in both surface and groundwater. It was shown that ptaquiloside leached off bracken...... fronds (the leaves of ferns) in concentrations up to 169 µ/L during rainfall events. Rainfall further determined the concentration in a stream that drained a bracken-covered catchment, suggesting that this is a potent driver of ptaquiloside exposure in the environment. In both pure and natural waters, p...

  6. Ptaquiloside, the major carcinogen of bracken fern, in the pooled raw milk of healthy sheep and goats: an underestimated, global concern of food safety.

    Science.gov (United States)

    Virgilio, Antonella; Sinisi, Annamaria; Russo, Valeria; Gerardo, Salvatore; Santoro, Adriano; Galeone, Aldo; Taglialatela-Scafati, Orazio; Roperto, Franco

    2015-05-20

    Bracken fern (Pteridium aquilinum) is a worldwide plant containing toxic substances, which represent an important chemical hazard for animals, including humans. Ptaquiloside, 1, a norsesquiterpenoid glucoside, is the major carcinogen of bracken detected in the food chain, particularly in the milk from farm animals. To date, ptaquiloside has been shown in the milk of cows feeding on a diet containing bracken fern. This is the first study that shows the systematic detection of ptaquiloside, 1, and reports its direct quantitation in pooled raw milk of healthy sheep and goats grazing on bracken. Ptaquiloside, 1, was detected by a sensitive method based on the chemical conversion of ptaquiloside, 1, into bromopterosine, 4, following gas chromatography-mass spectrometry (GC-MS) analysis. The presence of ptaquiloside, 1, possibly carcinogenic to humans, in the milk of healthy animals is an unknown potential health risk, thus representing a harmful and potential global concern of food safety.

  7. The effect of nitrogen additions on bracken fern and its insect herbivores at sites with high and low atmospheric pollution

    Science.gov (United States)

    M.E. Jones; M.E. Fenn; T.D. Paine

    2011-01-01

    The impact of atmospheric pollution, including nitrogen deposition, on bracken fern herbivores has never been studied. Bracken fern is globally distributed and has a high potential to accumulate nitrogen in plant tissue. We examined the response of bracken fern and its herbivores to N fertilization at a high and low pollution site in forests downwind of Los Angeles,...

  8. Changes in soil solution chemistry of Andisols following invasion by bracken fern

    Science.gov (United States)

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

    1998-01-01

    Disturbed areas within the Grand Fir Mosaic (GFM) ecosystem of northern Idaho show little to no natural conifer regeneration. Clear-cut sites are invaded quickly by bracken fern successional communities and seem to be in an arrested state of secondary succession. This study compared the soil solution composition of Andisols supporting bracken fern successional...

  9. Distribution of the carcinogenic terpene ptaquiloside in bracken fronds, rhizomes (Pteridium aquilinum),and litter in Denmark

    DEFF Research Database (Denmark)

    Rasmussen, L. H.; Jensen, L. S.; Hansen, H. C. B.

    2003-01-01

    The distribution of ptaquiloside (PTA) was studied in four Danish bracken populations in order to evaluate the transfer of PTA from ferns to soil. Populations showed statistically significant differences in PTAcontents of fronds and rhizomes despite large in-site variations. The highest concentra......The distribution of ptaquiloside (PTA) was studied in four Danish bracken populations in order to evaluate the transfer of PTA from ferns to soil. Populations showed statistically significant differences in PTAcontents of fronds and rhizomes despite large in-site variations. The highest...... showed that water could leach PTA from bracken fronds, which is in support of the high soil contents observed at sites exposed to heavy showers just before sampling. The observed soil contents correspond to estimated soil solution concentrations of 200–8500 ¹g/liter, demonstrating a substantial risk...

  10. Ptaquiloside in bracken spores from Britain

    DEFF Research Database (Denmark)

    Rasmussen, Lars Holm; Schmidt, Bjørn; Sheffield, Elizabeth

    2013-01-01

    Secondary metabolites from bracken fern (Pteridium aquilinum (L.) Kuhn) are suspected of causing cancer in humans. The main carcinogen is the highly water-soluble norsesquiterpene glucoside ptaquiloside, which may be ingested by humans through food, e.g. via contaminated water, meat or milk. It has...... been postulated that carcinogens could also be ingested through breathing air containing bracken spores. Ptaquiloside has not previously been identified in bracken spores. The aim of the study was to determine whether ptaquiloside is present in bracken spores, and if so, to estimate its content...

  11. Sorption, degradation and mobility of ptaquiloside, a carcinogenic Bracken (Pteridium sp.) constituent, in the soil environment

    DEFF Research Database (Denmark)

    Rasmussen, Lars Holm; Lauren, Denis; Hansen, Hans Christian Bruun

    2005-01-01

    Ptaquiloside (PTA) is a carcinogenic norsesquiterpene glucoside produced by Bracken in amounts up to at least 13 500 mg m2. The toxin is transferred from Bracken to the underlying soil from where it may leach to surface and groundwaters impairing the quality of drinking water. The objectives of t...... where PTA and a non-sorbing tracer showed almost coincident break-through. Leaching of PTA to the aqueous environment will be most extensive on sandy soils, having pH >4 and poor in organic matter which are exposed to high precipitation rates during cold seasons.......Ptaquiloside (PTA) is a carcinogenic norsesquiterpene glucoside produced by Bracken in amounts up to at least 13 500 mg m2. The toxin is transferred from Bracken to the underlying soil from where it may leach to surface and groundwaters impairing the quality of drinking water. The objectives...... of the present study were to characterize the solubility, degradation and retention of PTA in soils in order to evaluate the risk for groundwater contamination. PTA was isolated from Bracken. The logarithmic octanol–water and ethyl acetate–water partitioning coefficients for PTA were 0.63 and 0.88, respectively...

  12. 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.

    Science.gov (United States)

    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

  13. Control of bracken (Pteridium aquilinum and feeding preferences in pastures grazed by wild ungulates in an area of the Northern Apennines (Italy

    Directory of Open Access Journals (Sweden)

    Giovanni Argenti

    2012-10-01

    Full Text Available The diminution of pastoral activities in marginal areas, and consequently of livestock grazing, implies a strong encroachment of invasive vegetation. The conservation of the open areas is however particularly important for wildlife management. With this aim, this paper describes the results obtained in a protected area on the Apennine mountains (Italy, encroached by Pteridium aquilinum (L. Kuhn. Two restoration practices were carried out by the Administration of the Regional Park of the Laghi di Suviana e Brasimone (Bologna, Italy, in order to reverse the infestation of bracken and restore pastures within the park. The pasture, only grazed by wild animals, was improved through different treatments (ploughing followed by cuttings vs harrowing, each followed by seeding of a forage mixture. Our results showed better performance of the ploughing both as pastoral value of recovered pasture and as botanical composition. Some differences in the effects of the two restoration techniques were also found on the biodiversity index and on floristic richness. Data about grazing selection of the single botanical species have also been collected. The tesults also showed different behaviour in feeding preferences for wild ungulates in comparison to domestic stocks, giving a better evaluation of the real forage availability for wild herbivores.

  14. Dissipation of pterosin B in acid soils - tracking the fate of the bracken fern carcinogen ptaquiloside

    DEFF Research Database (Denmark)

    Skourti-Stathaki, Eirini; Clauson-Kaas, Frederik; Brandt, Kristian Koefoed

    2016-01-01

    . In soil, Pterosin B is adsorbed more strongly and it is expected to have a slower turnover than ptaquiloside. We thus hypothesized that pterosin B may serve as an indicator for any past presence of ptaquiloside. Pterosin B degradation was studied in acid forest soils from bracken-covered and bracken...

  15. Phosphorus speciation by "3"1P NMR spectroscopy in bracken (Pteridium aquilinum (L.) Kuhn) and bluebell (Hyacinthoides non-scripta (L.) Chouard ex Rothm.) dominated semi-natural upland soil

    International Nuclear Information System (INIS)

    Ebuele, Victor O.; Santoro, Anna; Thoss, Vera

    2016-01-01

    Access to P species is a driver for plant community composition based on nutrient acquisition. Here we investigated the distribution and accumulation of soil inorganic P (Pi) and organic P (Po) forms in a bracken and bluebell dominated upland soil for the period between bluebell above ground dominance until biomass is formed from half bluebells and half bracken. Chemical characterisation and "3"1P Nuclear Magnetic Resonance spectroscopy was used to determine the organic and inorganic P species. Total P concentration in soils was 0.87 g kg"−"1, while in plants (above- and below-ground parts) total P ranged between 0.84–4.0 g kg"−"1 and 0.14–2.0 g kg"−"1 for bluebell and bracken, respectively. The P speciation in the plant samples was reflected in the surrounding soil. The main forms of inorganic P detected in the NaOH-EDTA soil extracts were orthophosphate (20.0–31.5%), pyrophosphate (0.6–2.5%) and polyphosphate (0.4–7.0%). Phytate (myo-IP_6) was the most dominant organic P form (23.6–40.0%). Other major peaks were scyllo-IP_6 and α- and β- glycerophosphate (glyP). In bluebells and bracken the main P form detected was orthophosphate ranging from (21.7–80.4%) and 68.5–81.1%, in above-ground and below-ground biomass, respectively. Other detected forms include α-glyP (4.5–14.4%) and β-glyP (0.9–7.7%) in bluebell, while in bracken they were detected only in stripe and blade in ranges of 2.5–5.5% and 4.4–9.6%, respectively. Pyrophosphate, polyphosphate, scyllo-IP_6, phosphonates, found in soil samples, were not detected in any plant parts. In particular, the high abundance of phytate in the soil and in bluebell bulbs, may be related to a mechanism through which bluebells create a recalcitrant phosphorus store which form a key part of their adaptation to nutrient poor conditions. - Highlights: • Organic P forms were the dominant P species detected in the bracken (Pteridium aquilinum) and bluebell (Hyacinthoides non-scripta) dominated

  16. Monoterpene emissions from an understory species, Pteridium aquilinum

    Science.gov (United States)

    Madronich, Monica B.; Greenberg, James P.; Wessman, Carol A.; Guenther, Alex B.

    2012-07-01

    Monoterpene emissions from the dominant understory species Pteridium aquilinum (Bracken fern) in a mixed temperate forest were measured in the field during the summers of 2006, 2007 and 2008. The results showed that Bracken fern emitted monoterpenes at different rates depending if the plants were located in the understory or in open areas. Understory plants emitted monoterpene levels ranging from 0.002 to 13 μgC gdw-1 h-1. Open area plants emitted monoterpene levels ranging from 0.005 to 2.21 μgC gdw-1 h-1. During the summer of 2008 greenhouse studies were performed to complement the field studies. Only 3% of the greenhouse Bracken fern plants emitted substantial amounts of monoterpenes. The average emission, 0.15 μgC gdw-1 h-1 ± 0.9 μgC gdw-1 h-1, was much lower than that observed in the field. The factors controlling monoterpene emissions are not clear, but this study provides evidence of the potential importance of understory vegetation to ecosystem total hydrocarbon emissions and emphasizes the need for longer-term field studies.

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

    Directory of Open Access Journals (Sweden)

    Connie O’Driscoll

    2016-04-01

    Full Text Available 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.

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

    Science.gov (United States)

    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.

  19. Spatial Characteristics of Edible Wild Fern Harvesting in Mountainous Villages in Northeastern Japan Using GPS Tracks

    Directory of Open Access Journals (Sweden)

    Toshiya Matsuura

    2014-02-01

    Full Text Available Wild plants in forests provide valuable living resources for rural communities. The location where local people harvest various species is important to the wise use of forest ecosystem services. Using global positioning system (GPS tracking of harvesters’ activities as well as geographic information system (GIS and a generalized linear model (GLM, this study analyzed the spatial differences among harvesting sites of three popular edible ferns, i.e., ostrich fern (Matteuccia struthiopteris, bracken (Pteridium aquilinum, and royal fern (Osmunda japonica, in mountainous villages of Northeastern Japan. The explanatory variables used were vegetation classes, terrain features, and proximity to roadways. The GLM yielded clear differences in harvesting sites among species that were affected by both the species’ ecological characteristics and human behavior. Ostrich fern was harvested mainly in canopy openings along valley floors, whereas royal fern harvest sites were frequently located in snow avalanche scrublands. Bracken was mainly harvested in deforested areas or young conifer plantations. Whereas ostrich fern and bracken harvest sites were restricted by the accessibility from roadways, this was not the case for royal fern. Potential harvest sites of ferns were estimated with the highest value for bracken. Our results suggest that local harvesters seriously consider various natural and anthropogenic factors to maintain effective and sustainable harvesting.

  20. Human gastric cancer, Helicobacter pylori and bracken carcinogens: A connecting hypothesis.

    Science.gov (United States)

    Oliveros-Bastidas, Alberto; Calcagno-Pissarelli, María Pía; Naya, Marlene; Ávila-Núñez, Jorge Luis; Alonso-Amelot, Miguel E

    2016-03-01

    Long term infection of Helicobacter pylori (Hp) virulent strains is a key factor in the genesis of human gastric cancer, and so are certain dietary proinflammatory and genotoxic compounds. Carcinogenic bracken fern (Pteridium spp.) is one of these. Toxins from this plant are consumed as bracken culinary preparations, through milk and meat of bracken-exposed livestock, and drain waters from bracken swards. Bracken toxin ptaquiloside (PtQ), a suspected human carcinogen, elicits complex responses in animals leading to death. PtQ and Hp might cooperate in gastric pathologies. This paper presents an hypothesis on PtQ-Hp association leading to the enhancement of carcinogenesis in the human gastric environment that might explain the high gastric cancer incidence and death rates among Hp-infected people living in bracken zones at two levels: (1) The macroscopic scale comprising the flow of PtQ in the human diet. (2) the microscopic scale encompassing (A) gastric luminal medium; (B) gastric mucus structure and mucin degradation elicited by Hp; (C) bacterial pH gradient modification of the gastric mucosa that favors PtQ survival and its penetration into epithelial tissue; (D) combined PtQ/Hp effects on gastric immune and inflammatory responses; (E) PtQ-Hp complementary activity at selected cell signaling cascades and genome disturbance. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Control of bracken (Pteridium aquilinum) and feeding preferences in pastures grazed by wild ungulates in an area of the Northern Apennines (Italy)

    OpenAIRE

    Argenti, Giovanni; Cervasio, Francesco; Ponzetta, Maria

    2012-01-01

    The diminution of pastoral activities in marginal areas, and consequently of livestock grazing, implies a strong encroachment of invasive vegetation. The conservation of the open areas is however particularly important for wildlife management. With this aim, this paper describes the results obtained in a protected area on the Apennine mountains (Italy), encroached by Pteridium aquilinum (L.) Kuhn. Two restoration practices were carried out by the Administration of the Regional Park of the Lag...

  2. Occurrence of the carcinogenic Bracken constituent ptaquiloside in fronds, topsoils and organic soil layers in Denmark

    DEFF Research Database (Denmark)

    Rasmussen, L.H.; Kroghsbo, S.; Frisvad, Jens Christian

    2003-01-01

    Bracken (Pteridium aquilinum (L.) Kuhn) is a common fern found on all continents except Antarctica. It is under suspicion of causing cancer among people who utilizes it as food. The main carcinogenic compound is thought to be the water-soluble compound ptaquiloside. Ptaquiloside-uptake may occur...... not only through food, but also via drinking water as ptaquiloside might leach from plant material. The purpose of the study was to identify environmental parameters that correlate with the ptaquiloside-content in fronds, and to quantify the amount of ptaquiloside in the soil environment. The ptaquiloside...

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

    DEFF Research Database (Denmark)

    Rasmussen, Lars Holm; Donnelly, Eric; Strobel, Bjarne W.

    2015-01-01

    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...... 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......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...

  4. Knowledge-Based Estimation of Edible Fern Harvesting Sites in Mountainous Communities of Northeastern Japan

    Directory of Open Access Journals (Sweden)

    Toshiya Matsuura

    2013-12-01

    Full Text Available Once local expert knowledge regarding the harvesting of various non-timber forest products (NTFPs is lost, it is difficult to recover. We investigated whether the knowledge of expert forest harvesters can be used to determine the habitat distribution and harvesting sites of three popular edible wild ferns, i.e., ostrich fern (Matteuccia struthiopteris, bracken (Pteridium aquilinum, and royal fern (Osmunda japonica, in mountainous communities of western Fukushima, Japan. Using multi-criteria evaluation (MCE based on the analytic hierarchy process (AHP and geographic information system (GIS, we found that harvesters were easily able to recognize differences in the spatial characteristics of the habitat distribution of fern species due to both natural and anthropogenic factors. These factors were described by various GIS layers, such as vegetation and terrain features (e.g., gradient, aspect, and slope position derived from a 20-m digital elevation model (DEM. Harvesting sites were limited by their distance from a roadway, which differed among species. By comparison with the GPS records of actual harvesting sites, we estimated the potential harvesting sites of each fern species with reasonable accuracy, particularly for bracken. Our results show that the knowledge of expert forest harvesters can be quantified using MCE and GIS, which is useful for determining the spatial characteristics of NTFP harvesting and ensuring sustainable management practices.

  5. Ptaquiloside in Pteridium aquilinum subsp. aquilinum and corresponding soils from the South of Italy: influence of physical and chemical features of soils on its occurrence.

    Science.gov (United States)

    Zaccone, Claudio; Cavoski, Ivana; Costi, Roberta; Sarais, Giorgia; Caboni, Pierluigi; Traversa, Andreina; Miano, Teodoro M

    2014-10-15

    The bracken fern Pteridium aquilinum (L.) Kuhn, one of the most common plant species on Earth, produces a wide range of secondary metabolites including the norsesquiterpene glucoside ptaquiloside (PTA). Several studies are present in literature about eco-toxicological aspects related to PTA, whereas results about the effect of growth conditions and soil properties on the production and mobility of PTA are sometimes conflicting and further investigations are needed. The aim of the present work is to investigate the occurrence and possible fate of PTA in soils showing different physical and chemical features, and collected in several areas of the South of Italy. The PTA content was determined in both soil and fern samples by GC-MS; both the extraction protocol and recovery were previously tested through incubation studies. Soils samples were also characterized from the physical and chemical points of view in order to correlate the possible influence of soil parameters on PTA production and occurrence. PTA concentration in P. aquilinum fern seemed to be significantly affected by the availability of nutrients (mainly P) and soil pH. At the same time, PTA concentration in soil samples was always undetectable, independent of the PTA concentration in the corresponding Pteridium samples and pedo-climatic conditions. This seems to suggest the degradation of the PTA by indigenous soil microbial community, whereas incubation studies underlined a certain affinity of PTA for both organic colloids and clay/silt particles. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. A genome or a memome? : the cause of the rise of Pteridium esculentum at c. 700 BP in pollen/spore records from Aotearoa/New Zealand

    International Nuclear Information System (INIS)

    Flenley, J.; Todd, A.

    2001-01-01

    In New Zealand palynology, a strong increase in abundance of the spores of Pteridium esculentum (the bracken fern) about 700 BP has been taken by some authors to be an indication of first colonisation by people. Earlier dates for this phenomenon have been rejected by these authors. In this paper we argue that rejection of these dates may be inappropriate. A preliminary statistical analysis shows that early dates tend to be near sea level, in climatically favourable areas, close to the coast or to navigable rivers, and in the north. This does not conflict with an early arrival of people and progressive spread later. To explain the fact that most inland, upland, climatically unfavourable and southern dates cluster around 700 BP, an alternative hypothesis is advanced: that it represents the establishment of the use of the bracken fern rhizome as a staple diet, allowing rapid expansion into areas virtually uninhabitable previously because of lack of a suitable crop. On this hypothesis it was the spread through an existing population of the memome (set of ideas) about fern use which caused the palynological change, not the spread of the genome (the human species). An analogy is drawn with the spread of agriculture into Western Europe in Neolithic times. (author). 41 refs., 5 figs., 2 tabs

  7. Natural regeneration of deforested areas dominated by Pteridium aquilinum (L. Kuhn located in the serra da mantiqueira mountain range

    Directory of Open Access Journals (Sweden)

    Selma Cristina Ribeiro

    2013-03-01

    Full Text Available This study was set out with the objective of analyzing successional process in areas which are deforested and dominated by Pteridium aquilinum in the Serra da Mantiqueira mountain range, by researching the natural regeneration of shrub and tree species and evaluating both disturbance history and the edaphic conditions on the natural regeneration community. This research investigated two abandoned pasture areas in Bocaina de Minas county exposed to natural regeneration intervals ranging from six years (area named 6A to twenty years (area named 20A. The inventory occurred from sixty plots of 10 m², where all samples surveyed were between 0.15 m and 3 m high. All samples were identified and both the diameter in ground level and total height of the specimens were measured. The survey totaled 1,159 samples and 53 species. Melastomataceae was registered with the highest species richness and the highest specimen abundance. The two sampled areas showed species composition differences, with Jaccard similarity coefficient equal to 3.7%. The canonical correspondence analysis showed the correlations between natural regeneration stratum and non-labile phosphorus and clay in the 6A area. On the other hand, the 20A area showed correlations between plant regeneration and the K, P, Ca²+, Al³+ levels, with higher pH levels, and with the sum of exchangeable bases. In addition, the vegetation surveyed in area 20A was correlated with higher Pteridium population density. The results showed that the dominance of Pteridium aquilinum leads to successional process under inhibition, in which the ferns act negatively on the richness and abundance of shrub populations. It was also confirmed the Pteridium's affinity to steep areas, mainly in higher altitudes, where the soil is acid, as well as its preference to disturbed areas. Moreover, we highlight the fragilities of the mountain environments and the importance of preserving natural vegetation, as well as the bracken

  8. Screening for Ptaquiloside in Ferns: Using Herbarium Specimens for Qualitative Mapping Purposes.

    Science.gov (United States)

    Rasmussen, Lars Holm; Pedersen, Henrik AErenlund

    2017-11-01

    Ptaquiloside (PTA) is a noxious carcinogen found widespread in Bracken (Pteridium sp.) but with scattered and unresolved distribution outside the genus. The carcinogen causes Bovine Enzootic Haematuria among cattle all-over the World and is under suspicion of causing human cancers. To set-up a methodology for large-scale qualitative studies on the distribution of PTA in ferns using already available herbarium specimens as source. PTA and the main degradation product pterosin B (PtB) were quantified in aqueous frond extracts by HPLC-DAD. PTA was quantified after forced reaction into PtB. Optimal reaction conditions were tested using hydrochloric acid, sulphuric acid, trifluoroacetic acid (TFA), acetic acid and temperature as the experimental variables. A pair-wise test for PTA degradation in plant-press were used to explore the effect of this preservation regime. A selection of up to 50 years old Bracken herbarium specimens were tested for PTA and PtB. The methodology was applied on 21 fern species from Denmark. An optimised TFA-based method results in 30.7% higher conversion and a 1:1 reaction between PTA and PtB. Full three-dimensional resolution of the analyte was obtained. Preservation of fronds in a plant press increase formation of PtB. Hence, the method is only suitable for qualitative studies. Presence of PTA and PtB were found in samples up to 50 years old. Among 21 ferns tested, the compounds were only found in Pteridium aquilinum. Herbarium specimens up to 50 years old can be used for explorative risk assessment of ferns using HPLC-DAD for quantification and identification. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  9. Uma comunidade sucessional dominada por Pteridium aquilinum ( L. Kuhn. no município de Lavras, estado de Minas Gerais A successional stage community dominated by Pteridium aquilinum (L. Kuhn. in Lavras County, MG, Brazil

    Directory of Open Access Journals (Sweden)

    G. de Martins

    1982-06-01

    Full Text Available Numa área situada no município de Lavras, MG, o desmatamento realizado há cerca de dez anos propiciou a formação de uma comunidade infestante dominada por Pteridium aquilium (L. Khun., te ndo como codominantes Imperara brasiliensis Trin. e Andropogon bicornis L.. Como fatores que mantém esta comu nidade devem ser considerados: a as queimadas intermiten te s; b a acidez do solo; c a alta percentagem de saturação de aluminio ; d a ação fitotóxica do próprio P. aquilinum; e a falta de palatabilidade das espécies dominantes.A forest was clearcutted about 10 years ago in Lavras county, MG, Brazil and today a natural successional stage community can be found. The dominant weed, in fitomass, coverage an hcight is the bracken-fern Pteridium aquilinum (L. Kuhn. The West Indian foxta il (Andropogon bicornis L. and the brazilian cogon grass (Imperata brasiliensis Trin. are the co-dominats weeds. Periodic burnings, soil acidity, high aluminium saturation and the phytotoxicity of the P. aquilinum itself are probably the factors which could explain the present community successional stage.

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

    Science.gov (United States)

    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.

  11. 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.

    Science.gov (United States)

    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

  12. First record of Pteridium caudatum (Dennstaedtiaceae) in Old Providence Island, Colombia

    International Nuclear Information System (INIS)

    Tobar Vargas, Alexandra; Gavio, Brigitte

    2011-01-01

    We report for the first time the presence of the invasive fern Pteridium caudatum (L.) Maxon Old Providence Island, Colombia. The species was found as an ornamental plant in house backyard, as well as in the wild in the locality the peak, the best preserved area of the island. We discuss the ecological implications associated to the presence of this species.

  13. Screening for ptaquiloside in ferns

    DEFF Research Database (Denmark)

    Rasmussen, Lars Holm; Pedersen, Henrik Ærenlund

    2017-01-01

    . Objective: To set-up a methodology for large-scale qualitative studies on the distribution of PTA in ferns using already available herbarium specimens as source. Methodology: PTA and the main degradation product pterosin B (PtB) were quantified in aqueous frond extracts by HPLC-DAD. PTA was quantified after...... of the analyte was obtained. Preservation of fronds in a plant press increase formation of PtB. Hence, the method is only suitable for qualitative studies. Presence of PTA and PtB were found in samples up to 50 years old. Among 21 ferns tested, the compounds were only found in Pteridium aquilinum. Conclusion...

  14. Сhanges in consumer properties of bracken using different storage methods

    Directory of Open Access Journals (Sweden)

    I. V. Shalisko

    2016-01-01

    Full Text Available The article compares the changes in consumer properties of bracken ordinary young shoots at different storage methods. Bracken is a source of vitamins, minerals, it is eaten in some countries -Japan, China, Korea, and also in Russia Shows some advantages in frozen storage. The structural and mechanical changes at themacro and micro levels. Compares elasticity raw samples at different storage methods. Data on the content of amino acids, fatty acids, vitamins, salt, water activity. From the obtained results revealed that the amino acid content in the composition of the frozen bracken decreased significantly as compared to fresh and salt fern (except aspartic acid, isoleucine, and leucine, whose number is close to their number in the salty fern. When storing the fern frozen there is a considerable amount of lipids. Also a significant presence of fat-tion of acids (as % of value, ±10% palmitic (24,86%, hexadecanoate (2,33%, stearic (1,06%, oleic (4,71%, linoleic (26,02%, α-linolenic (11,88%, γ-linolenic (3,13%, dihomo-γ-linolenic (2,28%, arahidonova (0,78%, arachidonic (14,83%, timonova (0,92%, Baganova (0,96%. There is the presence of essential fatty acids. Myristic, berestyeneva, palmitoleate, zonvakantie, andonova acids are present in smaller amount benefits. The results of determination of vitamins in the frozen samples showed that, despite significant losses in storage, they manage to keep the vitamins. It proposed the introduction of the freeze as an effective method of storage bracken. Storage method shoots bracken almost not been studied in frozen form, and it may be that innovation, which will expand the practical use of this type of native raw materials.

  15. Разработка теоретической модели совершенствования технологии получения хлеба, галет и сахарного печенья с использованием полуфабрикатов из орляка обыкновенного (Pteridium aquilinum)

    OpenAIRE

    Мельникова Е.В.

    2016-01-01

    Classification and scientific hypothesis of pro-cess efficiency lines for production of bread and flour confectionery products using semi-finished products from vegetable raw materials Pteridium aquilinum are suggested. The purpose of this study was to create a theoretical model for improving the technology of production of bread, biscuits, and sugar cookies, adapted to the use of semi-finished products from bracken (Pteridium aquilinum). Methods of system analysis, mathematical model-ing and...

  16. The Evaluation of High Resolution Aerial Imagery for Monitoring of ...

    African Journals Online (AJOL)

    The Royal Natal National Park and the Rugged Glen Nature Reserve are part of the uKhahlamba Drakensberg Park (UDP) World Heritage Site and have infestations of bracken fern (Pteridium aquilinum [L.] Kuhn). Prior image classification research on bracken fern were constrained by low resolution satellite imagery and ...

  17. Bracken: estimating species abundance in metagenomics data

    Directory of Open Access Journals (Sweden)

    Jennifer Lu

    2017-01-01

    Full Text Available Metagenomic experiments attempt to characterize microbial communities using high-throughput DNA sequencing. Identification of the microorganisms in a sample provides information about the genetic profile, population structure, and role of microorganisms within an environment. Until recently, most metagenomics studies focused on high-level characterization at the level of phyla, or alternatively sequenced the 16S ribosomal RNA gene that is present in bacterial species. As the cost of sequencing has fallen, though, metagenomics experiments have increasingly used unbiased shotgun sequencing to capture all the organisms in a sample. This approach requires a method for estimating abundance directly from the raw read data. Here we describe a fast, accurate new method that computes the abundance at the species level using the reads collected in a metagenomics experiment. Bracken (Bayesian Reestimation of Abundance after Classification with KrakEN uses the taxonomic assignments made by Kraken, a very fast read-level classifier, along with information about the genomes themselves to estimate abundance at the species level, the genus level, or above. We demonstrate that Bracken can produce accurate species- and genus-level abundance estimates even when a sample contains multiple near-identical species.

  18. Composition of bracken: some major- and trace-element constituents

    Energy Technology Data Exchange (ETDEWEB)

    Hunter, J G

    1953-01-01

    Periodic samples of bracken taken during the growing season have shown that the concentration of major elements (except calcium and sodium) decreases with age in fronds, and remains relatively constant in rhizomes, whereas trace-element concentration varies widely. Soil type has little effect on the mineral composition of fronds. Examination of three rhizome types revealed no wide differences in the content of major elements; pinnules generally contained higher concentrations of major and trace elements than fronds. Comparison of results with those published elsewhere for moorland plants grown under similar conditions indicates that bracken contains more potassium and less molybdenum.

  19. Between Two Fern Genomes

    Science.gov (United States)

    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

  20. Analysis of Pteridium ribosomal RNA sequences by rapid direct sequencing.

    Science.gov (United States)

    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.

  1. Spanish Translation and Validation of the Bracken Basic Concept Scale.

    Science.gov (United States)

    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)

  2. Genotoxic activity and inhibition of soil respiration by ptaquiloside, a bracken fern carcinogen

    DEFF Research Database (Denmark)

    Schmidt, Bjørn; Rasmussen, L.H.; Svendsen, Gitte Winkel

    2005-01-01

    . with an upper 95% confidence limit of 43 mu g PTA/g dry soil and a 95% lower confidence limit of -infinity mu g PTA/g dry soil. For Soil material sampled in late winter, initial PTA concentrations ranging from 1.56 to 212 mu g PTA/g dry soil were tested, resulting in an ED10 value of 55 mu g PTA/g, dry soil...

  3. Ptaquiloside in irish bracken ferns and receiving waters, with implications for land managers

    DEFF Research Database (Denmark)

    O'Driscoll, Connie; Ramwell, Carmel; Harhen, Brendan

    2016-01-01

    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...

  4. Determination of ptaquiloside and pterosin B derived from bracken (Pteridium aquilinum) in cattle plasma, urine and milk

    DEFF Research Database (Denmark)

    Aranha, Paulo Cesar Reis; Hansen, Hans Chr. Bruun; Rasmussen, Lars Holm

    2014-01-01

    in plasma, urine andmilk followed by LC–MS quantification. The average recovery of PTA in plasma, urine, and milk was 71,88 and 77%, respectively, whereas recovery of PTB was 75, 82 and 63%. The method LOQ for PTA andPTB in plasma was 1.2 and 3.7 ng mL−1, 52 and 33 ng mL−1for undiluted urine and 5.8 and 5...

  5. The omnipresent water fern

    NARCIS (Netherlands)

    Nierop, K.G.J.; Speelman, E.N.; de Leeuw, J.W.; Reichart, G.J.

    2011-01-01

    Several studies have reported the presence of large amounts of lignin in ubiquitously occurring species of the freshwater fern Azolla. Molecular analysis using flash pyrolysis and thermally assisted hydrolysis and methylation shows, however, that neither the leaves nor the roots of Azolla contain

  6. Fern of the future?

    NARCIS (Netherlands)

    Brinkhuis, H.; Bijl, P.K.

    Held in the palm of a human hand, a single specimen of Azolla filiculoides looks downright inconsequential. Even with the scaly leaves of this miniature aquatic fern spread flat, it barely spans the distance between the creases that cleave the flesh. Its fibrous root tendrils dangle like a lock of

  7. The morphology of ferns

    NARCIS (Netherlands)

    Holttum, R.E.

    1959-01-01

    A fern plant consists of a stem, bearing leaves and roots. The leaves (or some of them) bear dehiscent sporangia, each sporangium containing unicellular spores, which are in most cases Wind-dispersed. A spore germinates to produce a small green plant called a prothallus. The Prothallus bears sexual

  8. Intoxicação aguda por Pteridium arachnoideum e Pteridium caudatum em bovinos e distribuição das plantas em Mato Grosso

    Directory of Open Access Journals (Sweden)

    Fernando Henrique Furlan

    2014-04-01

    Full Text Available São descritos os aspectos epidemiológicos, clínicos e patológicos de um surto de intoxicação por Pteridium arachnoideum e Pteridium caudatum em bovinos no Estado de Mato Grosso. A distribuição dessas plantas no Estado, a intensidade de invasão de pastagens e alguns fatores associados à invasão das pastagens por Pteridium spp. são também descritos. Pteridium spp. foi observada em 83 propriedades de nove municípios de Mato Grosso e deste total, amostras de 22 propriedades foram coletadas para identificação taxonômica. Em 22 propriedades identifica-se P. arachnoideum e em duas dessas havia também P. caudatum. O desmatamento e a realização de queimadas parecem estar relacionados com a invasão de Pteridium spp. nas pastagens. Na propriedade em que ocorreu a doença, 306 bovinos foram introduzidos em uma pastagem formada por Brachiaria brizantha intensamente invadida por P. arachnoideum e P. caudatum e desses 22 bovinos adoeceram e morreram. Os principais sinais clínicos foram febre alta, apatia, fadiga, fraqueza e decúbito. Na necropsia havia graus variáveis de hemorragias em vários órgãos e cavidades e infartos ocasionais. Microscopicamente, a alteração mais importante consistiu em aplasia severa da medula óssea vermelha. Os achados epidemiológicos, clínicos e patológicos associados à identoificação taxonômica da planta fundamentam o diagnóstico de intoxicação aguda por P. arachnoideum e P. caudatum em bovinos. O crescente desmatamento e a frequente utilização de queimadas em Mato Grosso podem contribuir para que esta doença venha a ser uma importante fonte de prejuízos para a pecuária do Estado.

  9. New species of Malaysian ferns

    NARCIS (Netherlands)

    Holttum, R.E.

    1962-01-01

    The present paper includes descriptions of several new species of ferns found among recent collections from various parts of Malaysia; also two new combinations of names of species which are of interest on account of their taxonomic history.

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

  12. A successional stage community dominated by Pteridium aquilinum (L.) Kuhn. in Lavras County, MG, Brazil

    OpenAIRE

    Martins, G. de; Carvalho, D.A. de

    1982-01-01

    Numa área situada no município de Lavras, MG, o desmatamento realizado há cerca de dez anos propiciou a formação de uma comunidade infestante dominada por Pteridium aquilium (L.) Khun., te ndo como codominantes Imperara brasiliensis Trin. e Andropogon bicornis L.. Como fatores que mantém esta comu nidade devem ser considerados: a) as queimadas intermiten te s; b) a acidez do solo; c) a alta percentagem de saturação de aluminio ; d) a ação fitotóxica do próprio P. aquilinum; e) a falta de pala...

  13. How early ferns became trees.

    Science.gov (United States)

    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.

  14. Microbial degradation and impact of Bracken toxin ptaquiloside on microbial communities in soil

    DEFF Research Database (Denmark)

    Engel, Pernille; Brandt, Kristian Koefoed; Rasmussen, Lars Holm

    2007-01-01

    ), but not in the NZ soil (weak acid loamy Entisol). In the DK soil PTA turnover was predominantly due to microbial degradation (biodegradation); chemical hydrolysis was occurring mainly in the uppermost A horizon where pH was very low (3.4). Microbial activity (basal respiration) and growth ([3H]leucine incorporation...... assay) increased after PTA exposure, indicating that the Bracken toxin served as a C substrate for the organotrophic microorganisms. On the other hand, there was no apparent impact of PTA on community size as measured by substrate-induced respiration or composition as indicated by community......-level physiological profiles. Our results demonstrate that PTA stimulates microbial activity and that microorganisms play a predominant role for rapid PTA degradation in Bracken-impacted soils....

  15. Ecological anatomy of ferns fronds

    Directory of Open Access Journals (Sweden)

    Nina M. Derzhavina

    2014-04-01

    Full Text Available Structural types of frond anatomy are distinguished on the basis of investigation of 30 species of homosporous ferns and with regard for literature: hydromorphic, hygromorphic, mesomorphic, subxeromorphic, and subsucculent (cryptic succulent. Following frond traits are of highest adaptive value: their area and thickness, type of mesophyll, dry weight of an area unit – specific superficial density, cellular volume, and number of cells per unit of frond area.

  16. Ferns diversified in the shadow of angiosperms.

    Science.gov (United States)

    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.

  17. A comparative study of resource allocation in Pteridium in different Brazilian ecosystems and its relationship with European studies

    Directory of Open Access Journals (Sweden)

    DM Silva Matos

    Full Text Available Pteridium is a cosmopolitan genus that acts as an invasive species in many parts of the world. Most research on this genus has occurred in Europe, and there is a lack of data on it from South America, in spite of causing considerable conservation problems. We compared the biomass allocation of P. esculentum subsp. arachnoideum in two ecosystems in Brazil - Atlantic forest and Brazilian savanna. We measured the biomass of fronds, rhizomes and above-ground litter. We also compared the density, length and biomass of fronds from this Brazilian study with similar data of P. esculentumsubsp. arachnoideum derived from Venezuela and P. aquilinum from Europe. P. esculentum subsp. arachnoideum showed a wide response range. We found a negative relationship between frond and necromass, indicating a negative feedback effect, while a positive relationship was observed between frond and rhizome biomass. The continental comparison of relationships showed that Pteridium responds in a different way in both Brazil and Europe, and that in Brazil fronds tend to be longer and heavier, presumably as a result of the continuous growing season in South America while is shortened in Europe by frost. The paper shows the ability of Pteridium to adapt to different ecosystems.

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

    DEFF Research Database (Denmark)

    Clauson-Kaas, Frederik; Ramwell, Carmel; Hansen, Hans Chr. Bruun

    2016-01-01

    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...... 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...

  19. rFerns: An Implementation of the Random Ferns Method for General-Purpose Machine Learning

    Directory of Open Access Journals (Sweden)

    Miron B. Kursa

    2014-11-01

    Full Text Available Random ferns is a very simple yet powerful classification method originally introduced for specific computer vision tasks. In this paper, I show that this algorithm may be considered as a constrained decision tree ensemble and use this interpretation to introduce a series of modifications which enable the use of random ferns in general machine learning problems. Moreover, I extend the method with an internal error approximation and an attribute importance measure based on corresponding features of the random forest algorithm. I also present the R package rFerns containing an efficient implementation of this modified version of random ferns.

  20. SURVEY OF ORNAMENTAL FERNS, THEIR MORPHOLOGY AND ...

    African Journals Online (AJOL)

    ornamental ferns for environmental management and economic values. ... little variations in the structures of rhizome except in Phymatodes .... forms such as erect, tall, open, bushy and .... linear leaflet with acute apex and flat, glabrous lamina.

  1. Random clustering ferns for multimodal object recognition

    OpenAIRE

    Villamizar Vergel, Michael Alejandro; Garrell Zulueta, Anais; Sanfeliu Cortés, Alberto; Moreno-Noguer, Francesc

    2017-01-01

    The final publication is available at link.springer.com We propose an efficient and robust method for the recognition of objects exhibiting multiple intra-class modes, where each one is associated with a particular object appearance. The proposed method, called random clustering ferns, combines synergically a single and real-time classifier, based on the boosted assembling of extremely randomized trees (ferns), with an unsupervised and probabilistic approach in order to recognize efficient...

  2. Trends and concepts in fern classification

    Science.gov (United States)

    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

  3. Trends and concepts in fern classification.

    Science.gov (United States)

    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

  4. Chloroplast Genome Evolution in Early Diverged Leptosporangiate Ferns

    OpenAIRE

    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. c...

  5. Stoichiometry of ferns in Hawaii: implications for nutrient cycling.

    Science.gov (United States)

    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.

  6. Habitat Characteristics of Bracken-Covered Areas Intended for Afforestation in Ličko Sredogorje

    Directory of Open Access Journals (Sweden)

    Zvonko Seletković

    2013-12-01

    Full Text Available Background and Purpose: Forest cultures in continental part of Croatia are mainly based on bracken-covered areas and moors on deserted agriculture soils and pastures. Successful afforestation i.e. establishment of forest cultures depends among other things on the understanding of habitats and ecology of forest trees. The choice of best species of forest trees for afforestation needs to be based on the research in soil and climate characteristics of target habitats. The aims of this research were to show mesoclimatic characteristics of Ličko sredogorje and microclimatic and pedological characteristics of Ličko polje. Also, based on habitat characteristics and ecology of forest trees, the aim was to determine species of forest trees suitable for afforestation of bracken-covered areas. Materials and Methods: Climate, microclimate, pedological and plant nutrition researches were done at the area of Lika highlands. Climate analysis was done according to air temperatures, amount of precipitation, relative air humidity and other climate elements and appearances. Composite soil samples were taken from the depth of 0-30 cm in order to determine plant nutrition potential. Samples were prepared for further analysis in the laboratory. Results: The highest average annual air temperature of 9.6 °C was found at weather station Gračac and the lowest at Korenica station (8.1 °C. Average amount of precipitation for this region was around 1500 mm. Monthly rain factors were ranging from arid to perhumid. Considering thermal character of the climate, the area has moderately warm climate. Average volumetric soil humidity is 14.2 %. Soil has strong acid reaction, is very humus, good to richly supplied with total nitrogen, content of physiologically active phosphorus and potassium is low, and C/N ration normal. Conclusions: According to habitat characteristics in the area of Ličko sredogorje and ecological demands of forest tree species, forest cultures of Common

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

    Science.gov (United States)

    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

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

    Directory of Open Access Journals (Sweden)

    Yang Yong-Xia

    2009-06-01

    Full Text Available Abstract Background 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. Results 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. Conclusion By comparing four fern cp genome sequences it was confirmed that two major rearrangements distinguish higher leptosporangiate ferns from basal fern lineages. The

  9. The fern sporangium: an ultrafast natural catapult

    Science.gov (United States)

    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.

  10. Tear ferning test in healthy dogs.

    Science.gov (United States)

    Oriá, Arianne P; Raposo, Ana Claudia S; Araújo, Nayone L L C; Lima, Felipe B; Masmali, Ali M

    2017-11-07

    To evaluate and compare three tear sampling methods using two grading scales for administering the tear ferning test (TFT) to healthy dogs. In total, 90 dogs (180 eyes) were subjected to tear sampling using millimetered strips, reused after the Schirmer tear test (STT) (Schirmer group, SG). Then, the dogs were subdivided into three groups according to sampling approach: micropipette (MPG), microcapillary (MCG), and Schirmer sample 2 (S2G). The collected tears were dried on a clean microscope glass slide at room temperature and humidity. The ferning patterns were observed under a polarized light microscope and classified according to the Rolando and Masmali grading scales. Although all three methods were feasible, the STT was easier to perform in clinical settings. Type I and Grade 1 were the most commonly observed (64.17% and 61.7%, respectively) regardless of collection method. There was no significant difference between the STT median values and the TFT classifications. The TFT is appropriate for dogs and can be performed using the three suggested sampling methods, with a higher frequency of Type I and Grade 1. Thus, it is possible to use both grading scales in the classification of tear ferning in dogs. © 2017 American College of Veterinary Ophthalmologists.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  13. Distribution and dynamics of hayscented fern following stand harvest

    Science.gov (United States)

    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...

  14. Towards resolving the complete fern tree of life.

    Science.gov (United States)

    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.

  15. Chloroplast genome evolution in early diverged leptosporangiate ferns.

    Science.gov (United States)

    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.

  16. A molecular phylogeny of scaly tree ferns (Cyatheaceae).

    Science.gov (United States)

    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.

  17. The evolution, morphology and development of fern leaves

    Directory of Open Access Journals (Sweden)

    Alejandra eVasco

    2013-09-01

    Full Text Available 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 nearl 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.

  18. Spectroscopic Analysis of Arsenic Uptake in Pteris Ferns

    Directory of Open Access Journals (Sweden)

    Terrence Slonecker

    2009-09-01

    Full Text Available Two arsenic-accumulating Pteris ferns (Pteris cretica mayii and Pteris multifida, along with a non-accumulating control fern (Nephrolepis exaltata were grown in greenhouse conditions in clean sand spiked with 0, 20, 50, 100 and 200 ppm sodium arsenate. Spectral data were collected for each of five replicates prior to harvest at 4-week intervals. Fern samples were analyzed for total metals content and Partial Least Squares and Stepwise Linear Regression techniques were used to develop models from the spectral data. Results showed that Pteris cretica mayii and Pteris multifida are confirmed hyperaccumulators of inorganic arsenic and that reasonably accurate predictive models of arsenic concentration can be developed from the first derivative of spectral reflectance of the hyperaccumulating Pteris ferns. Both the arsenic uptake and spectral results indicate that there is some species-specific variability but the results compare favorably with previously published data and additional research is recommended.

  19. THE ANTIMICROBIAL ACTIVITY OF SOME EXTRACTS OF FERN GAMETOPHYTES

    Directory of Open Access Journals (Sweden)

    Ionica Deliu

    2013-12-01

    Full Text Available The nature freely offers us many resources for health and beauty. The ferns and their therapeutic properties are less exploit in Romania, except Lycopodium clavatum and Equisetum arvense. Some of the fern properties were demonstrated, like antioxidant, antimicrobial, antiviral, antihelmintic properties. Plants are reasonable alternative to synthetic drugs, avoid the side effect and high cost of synthetic drugs production. Also, the drug resistance bacteria can be controlled using plant derived remedies. In this study the antimicrobial effect of methanolic and ethanolic extracts from three fern species were tested. The extracts were gained from gametophytic stage of ferns obtained in vitro. The most obvious effect was observed for Asplenium trichomanes-ramosum extract. The total polyphenols and flavonoids content were established, too.

  20. Organelle Genome Inheritance in Deparia Ferns (Athyriaceae, Aspleniineae, Polypodiales

    Directory of Open Access Journals (Sweden)

    Li-Yaung Kuo

    2018-04-01

    Full Text Available Organelle genomes of land plants are predominately inherited maternally but in some cases can also be transmitted paternally or biparentally. Compared to seed plants (>83% genera of angiosperms and >12% genera of gymnosperms, plastid genome (plastome inheritance has only been investigated in fewer than 2% of fern genera, and mitochondrial genome (mitogenome from only one fern genus. We developed a new and efficient method to examine plastome and mitogenome inheritance in a fern species—Deparia lancea (Athyriaceae, Aspleniineae, Polypodiales, and found that plastid and mitochondrial DNAs were transmitted from only the maternal parentage to a next generation. To further examine whether both organelle genomes have the same manner of inheritance in other Deparia ferns, we sequenced both plastid and mitochondrial DNA regions of inter-species hybrids, and performed phylogenetic analyses to identify the origins of organellar DNA. Evidence from our experiments and phylogenetic analyses support that both organelle genomes in Deparia are uniparentally and maternally inherited. Most importantly, our study provides the first report of mitogenome inheritance in eupolypod ferns, and the second one among all ferns.

  1. Evolutionary and ecological perspectives of Late Paleozoic ferns. Part III. Anachoropterid ferns (including Anachoropteris, Tubicaulis, the Sermayaceae, Kaplanopteridaceae and Psalixochlaenaceae)

    OpenAIRE

    Galtier, Jean; Phillips, Tom L.

    2014-01-01

    The anachoropterid ferns, previously assigned to the family Anachoropteridaceae, are a group of anatomically preserved late Paleozoic filicalean ferns characterized by a C-shaped foliar xylem with abaxially recurved arms (inversicatenalean anatomy) and two main protoxylem strands. The variously curved to strongly inrolled foliar xylem certainly reflects different evolutionary trends within the morphogenus Anachoropteris. The occurrence of two groups of Tubicaulis is supported by differences i...

  2. Reconstructed tree fern Alethopteris zeilleri (Carboniferous, Medullosales)

    Energy Technology Data Exchange (ETDEWEB)

    Zodrow, Erwin L. [Department of Earth Sciences, University College of Cape Breton, Sydney, Nova, Scotia (Canada B1P 6L2)

    2007-01-02

    From a smaller open-pit area in the roof shale of the basal Cantabrian coal seam in Sydney Coalfield, Cape Breton Island, Nova Scotia, Canada, large amounts of the pteridosperm foliage Alethopteris zeilleri (Ragot) were found. This foliage is associated with abundant, naked medullosalean axes and dichotomies of varying sizes, up to 0.80-m long, cauline structures 0.90 m and 1.3 m long, detached ovules assigned to Pachytesta incrassata Brongniart, rare male-pollen organs of the type Dolerotheca Halle, rooted tree ferns in life position, and one specimen each of a juvenile medullosalean frond and root mantle. The fossils are compression/impression-preserved, and the foliage yielded thickly cutinized cuticles with unoriented cells (57-103 by 27-57 {mu}m) in intercostal fields. Ultimate rachises, and abaxial surfaces (excluding costal fields) show a mixture of simple and complexly-branched trichomes, and two different structural bases. These, together with fractal dimensionality of curvatures of anticlinal walls in intercostal fields, have taxonomic potential for alethopterids. The finds suggest reconstructing A. zeilleri (Ragot) as a tree, 5-7 m high, that bore both P. incrassata Brongniart and Dolerotheca-type fructifications. Its habitat was low-land coastal plains in the Pennsylvanian coal swamps of ancestral Sydney Coalfield. (author)

  3. Occurrence and fate of the norsesquiterpene glucoside ptaquiloside (PTA) in soils

    Science.gov (United States)

    Zaccone, Claudio; Cavoski, Ivana; Costi, Roberta; Sarais, Giorgia; Caboni, Pierluigi; Miano, Teodoro M.; Lattanzio, Vincenzo

    2014-05-01

    The bracken fern Pteridium aquilinum (L.) Kuhn, one of the most common plant species on Earth, produces a wide range of secondary metabolites including the norsesquiterpene glucoside ptaquiloside (PTA). This bracken constituent causes acute poisoning, blindness and cancer in animals, and can be transferred to man when bracken is utilized as food. Also milk from cows eating bracken is thought to be the vector for the transfer of PTA to humans, as well as PTA-contaminated drinking waters. Although some studies on the effect of growth conditions and soil properties on the production and mobility of PTA have been carried out (mainly in the North of Europe), results are sometimes conflicting and further investigations are needed. The aim of the present work is to study the occurrence and the fate of PTA in soils showing different physico-chemical features, collected in different pedoclimatic areas (from the South of Italy), but having the extensive ("wild") livestock farming as common denominator. The PTA content was determined in both soil and fern samples by GC-MS; both the extraction protocol and recovery were previously tested through incubation studies. Soils samples were also characterizes from the physical and chemical point of view (pH, EC, texture, total carbonates, cation exchange capacity, organic C, total N, available nutrients and heavy metal concentration) in order to correlate the possible influence of soil parameters on PTA production, occurrence and mobility. PTA concentration in soil samples was always Pteridium samples (2-780 µg/g), ii) the soil organic matter content (ranging from 3.4 to 22.8%), iii) the soil pH (ranging from 5.9 to 6.6), iv) the soil texture, v) the depth (0-10 cm; 10-20 cm), and vi) precipitations (ranging from 780 to 960 mm/a). This seems to suggest the degradation of the PTA by indigenous microbial community

  4. Towards resolving the complete fern tree of life.

    Directory of Open Access Journals (Sweden)

    Samuli Lehtonen

    Full Text Available 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.

  5. (Pteridium aquilinum (L.) Kuhn)

    African Journals Online (AJOL)

    Zinhle

    ... Gorge Environmental Precinct is the displacement of natural habitat by other ... The WV-2 image was atmospherically corrected in Interface Data Language ... The overall, user's and producer's accuracies were calculated and reported for ... Visual inspection of the classified imagery (Figure 2) in concert with field data ...

  6. Analyis on the vascular epiphytes of tree ferns in a montane rain forest in Costa Rica

    OpenAIRE

    Jens Bittner; Javier Trejos Zelaya

    2009-01-01

    The relationships between epiphytes and host specifity are known. We investigated the relation between specific epiphytes and tree fern trunks. Only some epiphytes are frequent or very frequent on tree ferns. Most of the epiphyte species are unspecific on these trunks. Blechnum fragile are the only found exclusively on tree ferns. We also observed different epiphyte communities dependent on the tree fern species and the morphology of the tree trunk.

  7. Analyis on the vascular epiphytes of tree ferns in a montane rain forest in Costa Rica

    Directory of Open Access Journals (Sweden)

    Jens Bittner

    2009-02-01

    Full Text Available The relationships between epiphytes and host specifity are known. We investigated the relation between specific epiphytes and tree fern trunks. Only some epiphytes are frequent or very frequent on tree ferns. Most of the epiphyte species are unspecific on these trunks. Blechnum fragile are the only found exclusively on tree ferns. We also observed different epiphyte communities dependent on the tree fern species and the morphology of the tree trunk.

  8. El historiador Fernández de Piedrahita

    Directory of Open Access Journals (Sweden)

    Carlos López Narváez

    1964-10-01

    Full Text Available Varón de Dios, las letras y la patria, Lucas Fernández de Piedrahita nació en Santafé de Bogotá, el 6 de marzo de 1624, de hidalgo linaje por su padre español, y de principesca sangre materna, como que su progenitora, doña Catalina Collantes, esposa de don Domingo Fernández de Soto y Piedrahita, era nieta de doña Francisca Coya de la realeza inca del Perú.

  9. Uptake of rare earth elements by dryopteris erythrosora (autumn fern)

    International Nuclear Information System (INIS)

    Ozaki, Takuo; Enomoto, Shuichi

    2001-01-01

    Mechanisms of uptake of rare earth elements (REEs) were investigated, particularly those by REE accumulator species (autumn fern). Rare earth elements are practically insoluble under natural conditions, suggesting some unknown mechanisms in REE accumulator species. In the present investigation, two notable phenomena were observed. (1) Concerning the ionic-radius dependence of REE uptake by leaves, nonaccumulator species showed an extremely high uptake for Y compared with the adjacent-ionic-radius REEs in the multitracer, while accumulator species showed no anomaly. (2) REE uptake by autumn fern was influenced by the addition of chelating chemical reagents in the uptake solution, while no effect was observed for nonaccumulator species. (author)

  10. New observations and synthesis of paleogene heterosporous water ferns

    NARCIS (Netherlands)

    Collinson, M.E.; Smith, S.Y.; van Konijnenburg-van Cittert, J.H.A.; Batten, D.J.; Refidaff, C.; Barke, J.; Marone, F.

    Premise of research. Reproductive structures of modern genera of heterosporous water ferns (Marsileaceae and Salviniaceae) are widespread and abundant in plant mesofossil assemblages from the Paleogene. For Salviniaceae, whole fertile fossil plants give a good understanding of morphology. These

  11. In vitro mutagenesis of commercial fern, Asplenium nidus from spores

    International Nuclear Information System (INIS)

    Norazlina Noordin

    2004-01-01

    Asplenium is a largest, most diverse fern genera. One of the common species is Asplenium nidus, well known as Bird's-nest fern, a medium to large fern with erect, stout, unbranched rhizomes. In creating variability of ferns for the benefit of the ornamental plant industry, in vitro mutagenesis is used. In this study, spores of Asplenium nidus were collected from frond bearing mature sporangia. Spores were cultured in modified 1/2 MS basal medium supplemented with various combinations of 6-Benzylaminopurine (BAP) and Naphtalene Acetic Acid (NAA). Spore cultures were incubated in incubation room at 24 degree C with 16 hours photoperiod (3500 lux). It was found that, the most effective combinations were 1 mg/1 BAP + 0. 1 mg/1 NAA and 2mg/1 BAP + 0. 1 mg/1 NAA. Prothallus was formed after 10 days of cultures and gametophytes were formed 1 month later. These gametophytes were irradiated with Gamma ray at doses of 0, 20, 90, 120, 150 and 180 Gy. From the preliminary result obtained from this study, for generating variations and desired phenotypic expression for Asplenium nidus, recommended doses for in vitro mutagenesis using spores are between 90 Gy to 150 Gy. Gametophytes were subcultured at monthly interval to ensure further development and propagation. Frequent monitoring for any changes in the morphology of the irradiated Asplenium nidus plants were carried out. (Author)

  12. The omnipresent water fern Azolla caroliniana does not contain lignin

    NARCIS (Netherlands)

    Nierop, K.G.J.; Speelman, E.N.; Leeuw, J.W. de; Reichart, G.-J.

    2011-01-01

    Several studies have reported the presence of large amounts of lignin in ubiquitously occurring species of the freshwater fern Azolla. Molecular analysis using flash pyrolysis and thermally assisted hydrolysis and methylation shows, however, that neither the leaves nor the roots of Azolla contain

  13. Tear ferning in normal dogs and dogs with keratoconjunctivitis sicca ...

    African Journals Online (AJOL)

    This study evaluates tear ferning as an ancillary technique for the evaluation of the canine tear film in normal eyes and eyes affected by keratoconjunctivitis sicca (KCS). Thirty dogs with KCS and 50 control dogs with normal tear film were evaluated with a full ophthalmoscopic examination and a Schirmer tear test type 1 ...

  14. First megafossil evidence of Cyatheaceous tree fern from the Indian

    Indian Academy of Sciences (India)

    A part of the compressed tree fern axis with leaf and adventitious root scars in unusual arrangement from Plio–Pleistocene sediments of Arunachal Pradesh, India is described as Cyathea siwalika sp. nov. This record suggests that Cyathea was an important component of tropical evergreen forest in the area during the ...

  15. Instructions for collecting tree ferns of the family Cyatheaceae

    NARCIS (Netherlands)

    Holttum, R.E.

    1957-01-01

    The next monographic study which will be undertaken for the series Pteridophyta of the Flora Malesiana will be devoted to the tree ferns of the Cyatheaceae. In connection with the large size of these plants and the desirability of having more and complete material at our disposal, the following

  16. The colonisation of woodland gaps by ferns and horsetails

    NARCIS (Netherlands)

    Bremer, P.

    2010-01-01

    In the Voorsterbos, a planted woodland on a former sea-floor (the Netherlands), artificial gaps within stands of Fagus sylvatica on boulder clay were monitored for five or six years after cutting. Ten fern species and three species of horsetail established in these gaps, with Dryopteris cristata,

  17. New fern records for Kilimanjaro | Hemp | Journal of East African ...

    African Journals Online (AJOL)

    Working on the flora and vegetation of Mt Kilimanjaro, Tanzania, 17 ferns in 10 families were found that had not yet been recorded for the floral region T2. The altitudinal range, localities and habitat description are given for Adiantum raddianum, Asplenium bugoiense, Blechnum ivohibense, Blotiella stipitata, Dryopteris ...

  18. Three new fern records for Kilimanjaro | Hemp | Journal of East ...

    African Journals Online (AJOL)

    Working on the flora and vegetation of Mt. Kilimanjaro, Tanzania, three ferns in three families were found that are not yet recorded for the floral region T2. The altitudinal range, localities and habitat description are given for Adiantum reniforme, Azolla africana and Trichomanes radicans. Journal of East African Natural History ...

  19. Stasis and convergence characterize morphological evolution in eupolypod II ferns.

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

  2. Alvaro Fernández Pérez

    Directory of Open Access Journals (Sweden)

    Díaz Piedrahita Santiago

    1995-11-01

    Full Text Available Fue el Dr. Fernández miembro destacado de la comunidad botánica latinoamericana formada hacia la mitad del siglo, y en Colombia desempeñó un papel importante como miembro de planta del Herbario Nacional Colombiano y del Instituto de Ciencias Naturales de la Facultad de Ciencias de la Universidad Nacional de Colombia. Nació el Dr. Fernández el 11 de febrero de 1920 en la procera ciudad de Popayán, donde tras adelantar los estudios primarios y secundarios obtuvo en 1940 el título de bachiller en el Liceo de la Universidad del Cauca; cumplida esta etapa se desplazó a Bogotá, ingresando a la Universidad Nacional donde completó el plan de estudios de la carrera de Farmacia e inició el curso del doctorado que se ofrecía para la época.

  3. PIXE study on arsenic accumulation by a fern. Pteris vittata

    International Nuclear Information System (INIS)

    Yamazaki, H.; Ishii, K.; Matsuyama, S.

    2010-01-01

    Pteris vittata is a fern reported to be an arsenic hyper-accumulator. To develop the practical application of the fern to a phytoremediation technique, it is necessary to explicate the effective accumulation mechanism. In this study, the arsenic distribution and the elemental correlation in the cellular level were examined in the fronds supplied with arsenate and arsenite separately via xylem vessel using an in-air micro-PIXE system at Tohoku University. The difference in transportation rate between arsenate and arsenite as well as the translocation of elements necessary for plant metabolism was revealed in different tissues of the fronds accumulating arsenic in high concentration. Hence, the in-air micro-PIXE analysis is an effective measure for undertaking phytoremediation research of hyper-accumulator plants. (author)

  4. Somatic embryogenesis in ferns: a new experimental system.

    Science.gov (United States)

    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.

  5. The scaly tree ferns (Cyatheaceae-Polypodiopsida) of Brazil

    OpenAIRE

    Weigand, Anna; Lehnert, Marcus

    2016-01-01

    ABSTRACT A synopsis of all scaly tree fern species (Cyatheaceae) occurring in Brazil is presented. We recognize 51 species in three genera [Sphaeropteris one species, Alsophila four species (one subspecies, two varieties), and Cyathea 45 species (one variety) ] with 17 taxa being endemic to Brazil. One hybrid endemic to Brazil is recognized. Further included are five species that have not yet been recorded in Brazil, but are expected here because they are found in adjacent countries and occur...

  6. Sorption equilibrium of mercury onto ground-up tree fern.

    Science.gov (United States)

    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.

  7. Ferns: the missing link in shoot evolution and development

    Directory of Open Access Journals (Sweden)

    Andrew Robert George Plackett

    2015-11-01

    Full Text Available 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.

  8. Sorption equilibrium of mercury onto ground-up tree fern

    Energy Technology Data Exchange (ETDEWEB)

    Ho, Y.-S. [Department of Chemical Engineering, I-Shou University, No. 1, Section 1, Hsueh-Cheng Road, Ta-Hsu Hsiang, Kaohsiung County 840, Taiwan (China)], E-mail: ysho@isu.edu.tw; Wang, C.-C. [Department of Chemical Engineering, I-Shou University, No. 1, Section 1, Hsueh-Cheng Road, Ta-Hsu Hsiang, Kaohsiung County 840, Taiwan (China)

    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 {delta}G{sup o}, {delta}H{sup o}, and {delta}S{sup o}, were calculated and compared with the sorption of mercury by other sorbents.

  9. Sorption equilibrium of mercury onto ground-up tree fern

    International Nuclear Information System (INIS)

    Ho, Y.-S.; Wang, C.-C.

    2008-01-01

    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 ΔG o , ΔH o , and ΔS o , were calculated and compared with the sorption of mercury by other sorbents

  10. Morphology, Physiology, and Anatomy of Penny Fern (Drymoglossum phyloselloidesand Its Effect on Cocoa

    Directory of Open Access Journals (Sweden)

    Fitria Yuliasmara

    2013-08-01

    Full Text Available This study aims to determine the anatomy, physiology and morphology of penny fern (Drimoglosum phylloseloides and its effect on cocoa. Morphological observation of penny fern used microscope to observe the roots, stems, leaves and spores. Physiology of penny fern was observed based on number of stomata and stomatal conductance using stomata printing method, while the amount of chlorophyll based on spectrophotometric method and rate of transpiration used cobalt chloride paper. Penny fern anatomy on cross-sectional and longitudinal in roots, stems and leaves. Penny fern growth was observed based the length of tendrils once a week during rainy and dry season. While the effect of penny fern invasion was observed based on variable leaf area with gravimetric method, the cross-section of attacked cacao branch using microtom and microscope and chlorophyll content by chlorophyll meter. Results showed that penny fern is a epiphytic weed which was crassulaceae acid metabolism plants that have the ability to absorb carbon dioxide at night and carry out photosynthesis during the day with closed stomata. Penny ferns reproduce using spores. The growth rate of penny fern 2.18 cm/week during the dry season and while in rainy season 3.89 cm/week. Penny fern leaf contains 0.0212 mg/g chlorophyll. Penny fern stomata density was 18.33/mm 2 with a width of opening stomata at night 26.3 µm which caused a veryslow rate of transpiration of 0.69 mm 2 /seconds. The existence penny fern on cocoa decreased leaf area and chlorophyll content decreased crop productivity which was indicated by decreasing in number of flowers, number of small, medium fruit, and large pods. However it had no effect on the number of leaves on one side flush cocoa. Key words: Drimoglosum phylloseloides, weeds, decrease productivity, Theobroma cacao

  11. Colonisation of epiphytic ferns by skinks and geckos in the high canopy of a Bornean rainforest

    OpenAIRE

    Donald, J.; Clegg, J.; Ellwood, M. D. F.

    2017-01-01

    Nest site availability limits the fitness and survival of skinks and geckos, particularly in the canopy of tall tropical rainforests. We document the systematic colonisation and nest use of epiphytic bird’s nest ferns (Asplenium spp) by the gecko Hemiphyllodactylus typus and the skink Lipinia cf. vittigera. As part of a controlled experiment we placed 32 ferns of similar sizes in the high canopy of a lowland dipterocarp rainforest in Sabah, Malaysian Borneo. Half of these ferns, sampled after...

  12. Crowdfunding the Azolla fern genome project: a grassroots approach.

    Science.gov (United States)

    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.

  13. A Gompertz regression model for fern spores germination

    Directory of Open Access Journals (Sweden)

    Gabriel y Galán, Jose María

    2015-06-01

    Full Text Available Germination is one of the most important biological processes for both seed and spore plants, also for fungi. At present, mathematical models of germination have been developed in fungi, bryophytes and several plant species. However, ferns are the only group whose germination has never been modelled. In this work we develop a regression model of the germination of fern spores. We have found that for Blechnum serrulatum, Blechnum yungense, Cheilanthes pilosa, Niphidium macbridei and Polypodium feuillei species the Gompertz growth model describe satisfactorily cumulative germination. An important result is that regression parameters are independent of fern species and the model is not affected by intraspecific variation. Our results show that the Gompertz curve represents a general germination model for all the non-green spore leptosporangiate ferns, including in the paper a discussion about the physiological and ecological meaning of the model.La germinación es uno de los procesos biológicos más relevantes tanto para las plantas con esporas, como para las plantas con semillas y los hongos. Hasta el momento, se han desarrollado modelos de germinación para hongos, briofitos y diversas especies de espermatófitos. Los helechos son el único grupo de plantas cuya germinación nunca ha sido modelizada. En este trabajo se desarrolla un modelo de regresión para explicar la germinación de las esporas de helechos. Observamos que para las especies Blechnum serrulatum, Blechnum yungense, Cheilanthes pilosa, Niphidium macbridei y Polypodium feuillei el modelo de crecimiento de Gompertz describe satisfactoriamente la germinación acumulativa. Un importante resultado es que los parámetros de la regresión son independientes de la especie y que el modelo no está afectado por variación intraespecífica. Por lo tanto, los resultados del trabajo muestran que la curva de Gompertz puede representar un modelo general para todos los helechos leptosporangiados

  14. The scaly tree ferns (Cyatheaceae-Polypodiopsida of Brazil

    Directory of Open Access Journals (Sweden)

    Anna Weigand

    2016-01-01

    Full Text Available ABSTRACT A synopsis of all scaly tree fern species (Cyatheaceae occurring in Brazil is presented. We recognize 51 species in three genera [Sphaeropteris one species, Alsophila four species (one subspecies, two varieties, and Cyathea 45 species (one variety ] with 17 taxa being endemic to Brazil. One hybrid endemic to Brazil is recognized. Further included are five species that have not yet been recorded in Brazil, but are expected here because they are found in adjacent countries and occur literally on the border with Brazil. We present the first key covering the family for the whole territory of Brazil.

  15. Asplenium bird’s nest ferns in rainforest canopies are climate-contingent refuges for frogs

    Directory of Open Access Journals (Sweden)

    Brett R. Scheffers

    2014-12-01

    Full Text Available Epiphytes are important for canopy dwelling organisms because they provide a cool and moist microhabitat in the relatively hot and dry canopy. Here we examine whether epiphytic Asplenium ferns act as important habitats for arboreal frogs. We conducted extensive fern and habitat surveys for frogs in the Philippines, and complimented these surveys with roaming day and night canopy surveys to identify the full extent of habitat use across the vertical strata. We artificially dried ferns of various sizes to identify relationships between water and temperature buffering. Ferns are the preferred diurnal microhabitat and breeding habitat for arboreal frogs. A strong positive relationship exists between fern size and frog usage and abundance. Our drying experiments show that large ferns buffer maximum temperatures and reduce variability in temperatures, and buffering is directly linked to their hydration. Frogs are likely using large ferns for their moist, cool, environments for breeding and daytime retreat, which supports the buffered microhabitat hypothesis—these plants promote species coexistence through habitat creation and amelioration of physical stress. However, drying experiments suggest that this buffering is contingent on regular rainfall. Altered rainfall regimes could lead to the unexpected loss of the functional capacity of these important fern habitats. Keywords: Climate change, Functionality, Microhabitat, Refuge, Ectotherm, Precipitation

  16. Variation of functional clonal traits along elevation in two fern species

    International Nuclear Information System (INIS)

    Song, Y.B.; Chen, L.Y.; Xiong, W.

    2015-01-01

    Phenotypical plasticity is generally considered among adaptive strategies by which plants can cope with environmental variation in space and time. Although much is known about plasticity in seed plants in terms of functional clonal traits while little is known about ferns. Variation of functional clonal traits of two ferns Dicranopteris dichotoma and Diplopterygium glaucum among plots differing in elevation in a subtropical evergreen broad-leaved forest in southern China was investigated. Along with elevation increasing the two fern species showed similar variation pattern of functional clonal traits: stable spacer length, increasing specific spacer length and decreasing spacer weight per ramet and specific spacer weight. The two ferns species had similar variation pattern of ramet performance traits but different variation pattern of ramet population properties. These results suggest an evolutionary trade-off between functions of foraging for and storing of resources in the two ferns, with a functional preference for the foraging in response to environmental change. (author)

  17. In Vitro Conservation of Some Threatened and Economically Important Ferns Belonging to the Indian Subcontinent

    Directory of Open Access Journals (Sweden)

    Shastri P. Shukla

    2014-01-01

    Full Text Available This study was undertaken to identify methods of mass multiplication for five ornamental, economically important ferns (Nephrolepis biserrata (Sw. Schott., N. cordifolia cv. ‘‘duffii’’ (L. Presl., N. exaltata cv. bostoniensis (L. Schott., Pteris vittata L., and Cyclosorus dentatus Link., and three threatened ferns, namely, Cyathea spinulosa Wall. ex. Hook, Pityrogramma calomelanos (L. Link., and Microsorum punctatum (L. Schott., through in vitro techniques. Collections were made from different biodiversity zones of India including Northeast Himalayas, Kumaon Himalayas, and Western Ghat and successfully introduced and grown in a fern-house. Aseptic cultures were raised at the morphogenic level of callus, axillary shoot, multiple shoot, and rooted plants. An optimized medium is described for each fern species. Plantlets were also produced from spore culture of Cyathea spinulosa and successfully hardened under fern house conditions.

  18. Ultrasonic synthesis of fern-like ZnO nanoleaves and their enhanced photocatalytic activity

    International Nuclear Information System (INIS)

    Ma, Qing Lan; Xiong, Rui; Zhai, Bao-gai; Huang, Yuan Ming

    2015-01-01

    Graphical abstract: - Highlights: • Fern-like ZnO nanoleaves were synthesized by ultrasonicating Zn microcrystals in water. • A fern-like ZnO nanoleaf is a self-assembly of ZnO nanoplates along one ZnO nanorod. • Fern-like ZnO nanoleaves exhibit enhanced photocatalytic activity than ZnO nanocrystals. • The branched hierarchical structures are responsible for the enhanced photocatalytic activity. - Abstract: Two-dimensional fern-like ZnO nanoleaves were synthesized by ultrasonicating zinc microcrystals in water. The morphology, crystal structure, optical property and photocatalytic activity of the fern-like ZnO nanoleaves were characterized with scanning electron microscopy, X-ray diffraction, transmission electron microscopy, photoluminescence spectroscopy and ultraviolet–visible spectroscopy, respectively. It is found that one fern-like ZnO nanoleaf is composed of one ZnO nanorod as the central trunk and a number of ZnO nanoplates as the side branches in opposite pairs along the central ZnO nanorod. The central ZnO nanorod in the fern-like nanoleaves is about 1 μm long while the side-branching ZnO nanoplates are about 100 nm long and 20 nm wide. Further analysis has revealed that ZnO nanocrystals are the building blocks of the central ZnO nanorod and the side-branching ZnO nanoplates. Under identical conditions, fern-like ZnO nanoleaves exhibit higher photocatalytic activity in photodegrading methyl orange in aqueous solution than spherical ZnO nanocrystals. The first-order photocatalytic rate constant of the fern-like ZnO nanoleaves is about four times as large as that of the ZnO nanoparticles. The branched architecture of the hierarchical nanoleaves is suggested be responsible for the enhanced photocatalytic activity of the fern-like ZnO nanoleaves

  19. Conservation Priorities for Tree Ferns (Cyatheaceae in Sri Lanka

    Directory of Open Access Journals (Sweden)

    R. H. G. Ranil

    2011-09-01

    Full Text Available Diversity, phytogeography and conservation status of Sri Lankan tree-ferns are discussed in this paper. The family Cyatheaceae is represented by eight taxa (seven species and one doubtful variety in Sri Lanka with a high rate of endemism of 75%. Apart from Cyathea walkerae and C. gigantea, the other species are restricted to geographically isolated areas in the country with limited population sizes. Fortunately, all Sri Lankan species of Cyathea occur within the protected areas of the wet zone. However, ex situ conservation is limited to C. walkerae and C. crinita at Botanic Gardens in Hakgala. Despite the family being listed in Annex II of CITES, its species have not yet been assessed in Sri Lanka for the Red Listing criteria. Identification of the nature and level of threat to Sri Lankan Cyathea species is therefore a major priority, followed by the monitoring of populations in situ in protected areas in the wet zone. Ex situ conservation of rare species and cultivation of Cyathea species from spores have also been identified as priority areas. A strong programme should be developed with the National Herbarium to explore little known forest patches in the wet zone to enhance our knowledge of Cyathea species in Sri Lanka. Such information will provide a strong basis for preparing a conservation and management plan for tree-ferns in the country.

  20. Invariant Hough Random Ferns for Object Detection and Tracking

    Directory of Open Access Journals (Sweden)

    Yimin Lin

    2014-01-01

    Full Text Available This paper introduces an invariant Hough random ferns (IHRF incorporating rotation and scale invariance into the local feature description, random ferns classifier training, and Hough voting stages. It is especially suited for object detection under changes in object appearance and scale, partial occlusions, and pose variations. The efficacy of this approach is validated through experiments on a large set of challenging benchmark datasets, and the results demonstrate that the proposed method outperforms state-of-the-art conventional methods such as bounding-box-based and part-based methods. Additionally, we also propose an efficient clustering scheme based on the local patches’ appearance and their geometric relations that can provide pixel-accurate, top-down segmentations from IHRF back-projections. This refined segmentation can be used to improve the quality of online object tracking because it avoids the drifting problem. Thus, an online tracking framework based on IHRF, which is trained and updated in each frame to distinguish and segment the object from the background, is established. Finally, the experimental results on both object segmentation and long-term object tracking show that this method yields accurate and robust tracking performance in a variety of complex scenarios, especially in cases of severe occlusions and nonrigid deformations.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  3. THE DIVERSITY OF EPIPHYTIC FERN ON THE OIL PALM TREE (Elaeis guineensis Jacq. IN PEKANBARU, RIAU

    Directory of Open Access Journals (Sweden)

    Nery Sofiyanti

    2015-02-01

    Full Text Available Oil palm (Elaeis guineensis is one  main commodity in Riau Province. Morphologically, the trunk of oil palm  has suitable environment for the growth of epiphytic fern, due to its broaden base of petiole that may accumulate organic and anorganic debrish. The objective of this study was to investigate the diversity of epiphytic fern on the oil palm tree. A total of 125 oil palm trees from seven  study sites in Pekanbaru, Riau were observed. The number of epiphytic ferns identified in this study was 16 species belongs to six families.

  4. Neoplasmas da bexiga associados à hematúria enzoótica bovina Urinary bladder neoplasms associated with bovine enzootic hematuria

    Directory of Open Access Journals (Sweden)

    Marione de Albuquerque Moreira Souto

    2006-10-01

    Full Text Available Relatam-se três casos de hematúria enzoótica bovina (HEB em animais provenientes do município de Jaguari, RS, Brasil. As pastagens de todas as propriedades de origem estavam altamente infestadas por samambaia (Pteridium aquilinum. Três bovinos, com idades entre 4 e 7 anos, apresentaram sinais clínicos que incluíam emagrecimento progressivo, hematúria intermitente e palidez das mucosas. As principais lesões foram observadas na bexiga e consistiam de três tipos de neoplasmas: hemangioma capilar, hemangiossarcoma e carcinoma de células escamosas. A epidemiologia, os sinais clínicos e as lesões macroscópicas e microscópicas observadas nos três bovinos são consistentes com o diagnóstico de HEB.Three cases of bovine enzootic hematuria (BHE are described in cattle from the municipality of Jaguari, Rio Grande do Sul, Brazil. The pastures of all affected farms were highly infested with bracken fern (Pteridium aquilinum. Three 4-7-year-old bovine had clinical signs of progressive weight loss, intermittent hematuria, and mucosal pallor. The main lesions were observed in the urinary bladder and consisted of three types of neoplasms: capillary hemangioma, hemangiosarcoma, and squamous cell carcinoma. The epidemiology, the clinical signs, and the gross and microscopic lesions observed in all three bovine were of BHE.

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

    Science.gov (United States)

    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.

  6. Is there foul play in the leaf pocket? The metagenome of floating fern

    NARCIS (Netherlands)

    Dijkhuizen, L.W.; Brouwer, P.; Bolhuis, H.; Reichart, G.-J.; Koppers, N.; Huettel, B.; Bolger, A.M.; Li, F.-W.; Cheng, S.; Liu, X.; Wong, G.K.-S.; Pryer, K.; Weber, A.; Bräutigam, A.; Schluepmann, H.

    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

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

    Science.gov (United States)

    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…

  8. Elevated uptake of Th and U by netted chain fern (Woodwardia areolata)

    International Nuclear Information System (INIS)

    Knox, A.S.; Kaplan, D.I.; Hinton, T.G.

    2008-01-01

    We assessed the ability of netted chain fern (Woodwardia areolata) to uptake U and Th from wetland soils on the U.S. Department of Energy's Savannah River Site in South Carolina. Netted chain fern had the highest Th and U concentrations of all plants collected from the wetland. Ferns grown in contaminated soil (329 mg x kg -1 Th, 44 mg x kg -1 U) in a greenhouse contained 6.4 mg x kg -1 Th and 5.3 mg x kg -1 U compared with 0.13 mg x kg -1 Th and 0.035 mg x kg -1 U in Bermuda grass (Cynodon dactylon). Netted chain fern has potential for the phytoremediation of soils contaminated with Th and U. (author)

  9. PIXE study on absorption of arsenate and arsenite by arsenic hyperaccumulating fern (Pteris vittata)

    International Nuclear Information System (INIS)

    Yamazaki, H.; Ishii, K.; Matsuyama, S.

    2008-01-01

    Pytoremediation using an arsenic hyperaccumulator, Petris vittata L., has generated an increasing interest worldwide due to both environmentally sound and cost effectiveness. However the mechanism of arsenic accumulation by this fern is not clear at this time. This study examined the uptake of arsenate (As(V)) and arsenite (As(III)) by a hydroponic culture of Pteris vittata using both in-air submilli-PIXE for different parts of the fern and in-air micro-PIXE for the tissue cells. These PIXE analysis systems used 3 MeV proton beams from a 4.5-MV single-ended Dynamitron accelerator at Tohoku University, Japan. The fern took up both arsenate and arsenite from hydroponic solutions which were spiked with 50 mg of arsenic per litter. Final amount of arsenic accumulation in the fern is 1,500 mg per kg (wet weight) of the plant biomass in arsenite treatment and 1,100 mg per kg in arsenate treatment. Arsenic accumulation was not observed at the root parts of the ferns. The in-vivo mapping of elements by submilli-PIXE analyses on the fern laminas showed the arsenic accumulation in the edges of a pinna. The micro-PIXE analyses revealed arsenic maps homogeneously distributed in cells of the lamina, stem and rhizome of the fern. These results indicate that arsenic, both arsenate and arsenite in a contaminated medium are translocated quickly from roots to fronds of Pteris vittata, and distributes homogeneously into tissue cells of the fern laminas. (author)

  10. Global biogeography of scaly tree ferns (Cyatheaceae): evidence for Gondwanan vicariance and limited transoceanic dispersal

    OpenAIRE

    Korall, Petra; Pryer, Kathleen

    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 G...

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

    Science.gov (United States)

    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.

  12. Distribution and dynamics of the invasive native hay-scented fern

    Science.gov (United States)

    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...

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

    Science.gov (United States)

    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.

  14. Glycoside Hydrolase (GH) 45 and 5 Candidate Cellulases in Aphelenchoides besseyi Isolated from Bird?s-Nest Fern

    OpenAIRE

    Wu, Guan-Long; Kuo, Tzu-Hao; Tsay, Tung-Tsuan; Tsai, Isheng J.; Chen, Peichen J.

    2016-01-01

    Five Aphelenchoides besseyi isolates collected from bird's-nest ferns or rice possess different parasitic capacities in bird's-nest fern. Two different glycoside hydrolase (GH) 45 genes were identified in the fern isolates, and only one was found in the rice isolates. A Abe GH5-1 gene containing an SCP-like family domain was found only in the fern isolates. Abe GH5-1 gene has five introns suggesting a eukaryotic origin. A maximum likelihood phylogeny revealed that Abe GH5-1 is part of the nem...

  15. Survival and growth of epiphytic ferns depend on resource sharing

    Directory of Open Access Journals (Sweden)

    Hua-Zheng eLu

    2016-03-01

    Full Text Available Locally available resources can be shared within clonal plant systems through physiological integration, thus enhancing their survival and growth. Most epiphytes exhibit clonal growth habit, but few studies have tested effects of physiological integration (resource sharing on survival and growth of epiphytes and whether such effects vary with species. We conducted two experiments, one on individuals (single ramets and another on groups (several ramets within a plot, with severed and intact rhizome treatments (without and with physiological integration on two dominant epiphytic ferns (Polypodiodes subamoena and Lepisorus scolopendrium in a subtropical montane moist forest in Southwest China. Rhizome severing (preventing integration significantly reduced ramet survival in the individual experiment and number of surviving ramets in the group experiment, and it also decreased biomass of both species in both experiments. However, the magnitude of such integration effects did not vary significantly between the two species. We conclude that resource sharing may be a general strategy for clonal epiphytes to adapt to forest canopies where resources are limited and heterogeneously distributed in space and time.

  16. Arsenic in the rhizosphere soil solution of ferns.

    Science.gov (United States)

    Wei, Chaoyang; Zheng, Huan; Yu, Jiangping

    2012-12-01

    The aim of this study was to explore the evidence of arsenic hyperaccumulation in plant rhizosphere solutions. Six common fern plants were selected and grown in three types of substrate: arsenic (As) -tailings, As-spiked soil, and soil-As-tailing composites. A rhizobox was designed with an in-situ collection of soil solutions to analyze changes in the As concentration and valence as well as the pH, dissolved organic carbon (DOC) and total nitrogen (TN). Arsenite composed less than 20% of the total As, and As depletion was consistent with N depletion in the rhizosphere solutions of the various treatments. The As concentrations in the rhizosphere and non-rhizosphere solutions in the presence of plants were lower than in the respective controls without plants, except for in the As-spiked soils. The DOC concentrations were invariably higher in the rhizosphere versus non-rhizosphere solutions from the various plants; however, no significant increase in the DOC content was observed in Pteris vittata, in which only a slight decrease in pH appeared in the rhizosphere compared to non-rhizosphere solutions. The results showed that As reduction by plant roots was limited, acidification-induced solubilization was not the mechanism for As hyperaccumulation.

  17. Phylogenetic Relationships of the Fern Cyrtomium falcatum (Dryopteridaceae from Dokdo Island Based on Chloroplast Genome Sequencing

    Directory of Open Access Journals (Sweden)

    Gurusamy Raman

    2016-12-01

    Full Text Available Cyrtomium falcatum is a popular ornamental fern cultivated worldwide. Native to the Korean Peninsula, Japan, and Dokdo Island in the Sea of Japan, it is the only fern present on Dokdo Island. We isolated and characterized the chloroplast (cp genome of C. falcatum, and compared it with those of closely related species. The genes trnV-GAC and trnV-GAU were found to be present within the cp genome of C. falcatum, whereas trnP-GGG and rpl21 were lacking. Moreover, cp genomes of Cyrtomium devexiscapulae and Adiantum capillus-veneris lack trnP-GGG and rpl21, suggesting these are not conserved among angiosperm cp genomes. The deletion of trnR-UCG, trnR-CCG, and trnSeC in the cp genomes of C. falcatum and other eupolypod ferns indicates these genes are restricted to tree ferns, non-core leptosporangiates, and basal ferns. The C. falcatum cp genome also encoded ndhF and rps7, with GUG start codons that were only conserved in polypod ferns, and it shares two significant inversions with other ferns, including a minor inversion of the trnD-GUC region and an approximate 3 kb inversion of the trnG-trnT region. Phylogenetic analyses showed that Equisetum was found to be a sister clade to Psilotales-Ophioglossales with a 100% bootstrap (BS value. The sister relationship between Pteridaceae and eupolypods was also strongly supported by a 100% BS, but Bayesian molecular clock analyses suggested that C. falcatum diversified in the mid-Paleogene period (45.15 ± 4.93 million years ago and might have moved from Eurasia to Dokdo Island.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  20. Restoring Native Forest Understory: The Influence of Ferns and Light in a Hawaiian Experiment

    Directory of Open Access Journals (Sweden)

    Robert Shallenberger

    2013-03-01

    Full Text Available Ecological restoration is an increasingly important component of sustainable land management. We explore potential facilitative relationships for enhancing the cost-effectiveness of restoring native forest understory, focusing on two factors: (1 overstory shade and (2 possible facilitation by a fern (Dryopteris wallichiana, one of few native colonists of pasture in our montane Hawaiˈi study system. We planted 720 understory tree seedlings and over 4000 seeds of six species under six planting treatments: a full factorial combination of low, medium and high light, situating plantings in either the presence or absence of a mature fern. After three years, 75% of outplanted seedlings survived. Seedling survivorship was significantly higher in the presence of a fern (79% vs. 71% without a fern and in medium and low light conditions (81% vs. 64% in high light. Relative height was highest at low to medium light levels. After 2.2 years, 2.8% of the planted seeds germinated. We observed no significant differences in seed germination relative to light level or fern presence. Analyzing several approaches, we found nursery germination of seeds followed by outplanting ca. 20% less costly than direct seeding in the field. This study opens new questions about facilitation mechanisms that have the potential to increase the extent and effectiveness of restoration efforts.

  1. Lead accumulation in the aquatic fern Azolla filiculoides.

    Science.gov (United States)

    Oren Benaroya, Rony; Tzin, Vered; Tel-Or, Elisha; Zamski, Eli

    2004-01-01

    In this study, we characterized lead (Pb2+) accumulation and storage by the aquatic fern Azolla filiculoides. Lead precipitates were detected in the vacuoles of mesophyll cells of Azolla plants cultured for 6 d in rich growth medium containing 20 mg l(-1) Pb2+. Energy dispersive spectroscopy (EDS) analysis of the relative element content of leaves collected from these plants revealed a 100% increase in the levels of P, S, Na and Ca and a 40% decrease in Mg and Cl compared to the untreated plants. Both Azolla whole plants and isolated apoplasts were incubated for 6 d in 20 mg l(-1) Pb2+. Lead content in the whole plant composed 0.37%, 2.3% and 1.8% of the dry weight after 2, 4 and 6 d of growth, respectively, while the isolated Azolla apoplast contained 0.125%, 1.22% and 1.4% Pb2+, respectively. Lead content in Azolla whole plant increase by 200%, 100% and 22% after 2, 4 and 6 d of growth, respectively, when compared to Azolla apoplast. Dark, electron dense deposits of lead were observed in light and transmission electron microscope in leaf cells treated with lead. All the observed lead deposits were localized in vacuoles while larger lead deposits were found in mature leaves than in young leaves. No lead deposits were found in cells of the cyanobiont Anabaena when the plants were exposed to similar conditions. Activity and content of V-H+-ATPase were studied in Azolla plants grown in the presence of 20, 40 and 80 mg l(-1) of lead for a period of 4 d. Activity of V-H+-ATPase was increased by 190%, 210% and 220%, respectively, but the content of V-H+-ATPase was reduced by all lead concentrations. Copyright 2004 Elsevier SAS

  2. Gametophyte and sporophyte of tree ferns in vitro culture

    Directory of Open Access Journals (Sweden)

    Katarzyna Goller

    2011-01-01

    Full Text Available Experiments had been carried out on gametophytes and very young fronds of sporophytes with application of Murashige and Skoog (1962 medium. The paper described the results of 15 years in vitro experiments on 16 species of tree ferns belonging to various genera: Blechnum, Cibotium, Cyathea and Dicksonia. Genus Cyathea was represented by: C. australis (R.Br. Domin., C. capensis (L.f. Sm., C. cooperi (F.Muell. Domin, C. brownii Domin, C. dealbata (G.Forest Sw., C. dregei Kunze, C. leichhardtiana (F.Muell. Copel., C. robertsiana (F.Muell. Domin., C. schanschin Mart., C. smithii Hook.f. and Cyathea sp. In case of genus Dicksonia only two species were introduced into our experiments: D. fibrosa Colenso and D. sellowiana Hook.. Taxa Blechnum was presented by B. brasiliense Desv. and Cibotium by C. glaucum (Sm. Hook. and Arn. and C. schiedei Schltdl. and Cham.. The studied species presented various responses on culture conditions depending on the level of stage of development. Time required for spores germination differed between species and took from only a few to 16 weeks. Prothalium formations showed various types of growth presented by marginal meristems. For all investigated species long term gametophyte in vitro cultures was established. Mature gametophyte possessed functional antheridia and archegonia. Spontaneous fertilization helped to establish the culture of young sporophytes. For all species the ex vitro culture in greenhouse collection was established. Manipulation of sucrose content in the medium stimulated the multiplication of gametophytes, but its lack induced formation of gemmae. Apospory was observed when culture of very young fronds was extended for 6 months and new generation of gametophytes was developed. Finally, sporophytes of 12 species were obtained and they have been growing in our greenhouse.

  3. Abiotic factors drives floristic variations of fern's metacommunity in an Atlantic Forest remnant.

    Science.gov (United States)

    Costa, L E N; Farias, R P; Santiago, A C P; Silva, I A A; Barros, I C L

    2018-02-15

    We analyzed floristic variations in fern's metacommunity at the local scale and their relationship with abiotic factors in an Atlantic Forest remnant of northeastern Brazil. Floristic and environmental variations were accessed on ten plots of 10 × 20 m. We performed cluster analyses, based on Bray-Curtis dissimilarity index to establish the floristic relationship. The influence of abiotic factors: luminosity, temperature, relative air humidity and relative soil moisture was evaluated from a redundancy analysis. We found 24 species belonging to 20 genera and 12 families. The fern's flora showed high floristic heterogeneity (>75% for most of the plot's associations). The fern's metacommunity was structured along an abiotic gradient modulated by temperature, luminosity, and relative soil moisture.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

  7. Use of rbcL and trnL-F as a two-locus DNA barcode for identification of NW-European ferns: an ecological perspective

    NARCIS (Netherlands)

    Groot, de G.A.; During, H.J.; Maas, J.W.; Schneider, H.; Erkens, R.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

  8. Determination of heavy metals in soil and different parts of Diplazium esculentum (medicinal fern)

    Science.gov (United States)

    Jasim, Hind S.; Idris, Mushrifah; Abdullah, Aminah; Kadhum, A. A. H.

    2014-09-01

    Diplazium esculentum is a widely used medicinal fern in Malaysia and other regions worldwide. Heavy metals in plants should be determined because prolonged human intake of toxic trace elements, even at low doses, results in organ malfunction and causes chronic toxicity. Hence, substantial information should be obtained from plants that grow on soils containing high concentrations of heavy metals. This study aimed to determine the physicochemical characteristics of soil and heavy metal concentrations (Pb, Cr, Mn, Cu, and Zn) in different parts of D. esculentum and soil, which were collected from the fern garden of Universiti Kebangsaan Malaysia. Results showed that heavy metals were highly accumulated in D. esculentum roots.

  9. Fern extracts potentiate fluconazole activity and inhibit morphological changes in Candida species

    Directory of Open Access Journals (Sweden)

    Maria A. Freitas

    2017-11-01

    Conclusions: The extracts obtained from the fern species L. venustum and P. calomelanos dose not present significant antifungal activity. However, P. calomelanos potentiates the activity of fluconazole and both extracts inhibits the morphological changes in Candida species, indicating that they have potential pharmacological activity as modulators of fungal biology. Therefore, novel studies are required to characterize the interference of these extracts in the virulence and pathogenicity of Candida species as well as the potential of fern species to treat fungal infections.

  10. FURTHER NOTES ON THE FERN-GENUS HETEROGONIUM PRESL

    Directory of Open Access Journals (Sweden)

    R. E. HOLTTUM

    2015-11-01

    Full Text Available In the "Sarawak Museum Journal," volume V (1949, pages 156-166,I gave a revised account of the genus Heterogonium Presl, based on specimens in the Singapore herbarium. Dr M. A. Donk wrote subsequently pointing out that specimens at Bogor (Buitenzorg add materially to the information contained in that paper. The present paper gives the result of a study of the Bogor specimens. I am glad to express my gratitude to Dr Donk for calling my attention to species which I had overlooked when searching literature on Malaysian ferns for indications of affinity to Heterogonium. The Bogor material includes the type specimens of Acrostichum teysmannianum Bak., Phegopteris schizoloma v. A. v. R. Dryopteris sagenoides forma contracta v. A. v. R., Polybotrya nieuwenhuisii Racib. and Polybotrya nieuwenhuisii var. brooksii v. A. v. R., also many sheets of H. giganteum, and material of H. sagenoides from a wider geographic range than I had previously seen. Summarizing the results of the present paper, I have united H.nieuwenhuisii and H. stenosemioides of my former paper, and have also united H. saxicola with H. giganteum. Further, I now recognize a second exindusiate species allied to H. sagenoides; but the variation in pubescence among exindusiate specimens, as within the species H. sagenoides proper, is very considerable, and I find it very difficult to draw specific limits. It is likely that there are local races, but much more field work in many localities is necessary before one can speak with certainty about this or define their status taxonomically. One interesting fact is that no exindusiate specimens of this alliance have been found in the Malay Peninsula, whereas Peninsular collections of indusiate H. sagenoides aremore abundant than from any other area. It is especially the variation in pubescence among specimens of H. sagenoides, and the lack of clear-cut varieties or subspecies within the Malay Peninsula, that deters me from distinguishing more

  11. Alsophila weidenbrueckii (Cyatheaceae), a new scaly tree fern from Papua New Guinea

    NARCIS (Netherlands)

    Lehnert, M.

    2016-01-01

    The scaly tree fern Alsophila weidenbrueckii is described and illustrated as new to science. It occurs in the Bismarck range in north-eastern New Guinea at 1200–2100 m in evergreen wet mountain forest. The species reaches maturity at a comparatively old age and large size and regenerates only in

  12. Novel fungi from an ancient niche: lachnoid and chalara-like fungi on ferns

    NARCIS (Netherlands)

    Guatimosim, E.; Schwartsburd, P. B.; Crous, P. W.; Barreto, R. W.

    2016-01-01

    A survey was conducted in Brazil to collect fungi on ferns. Based on morphology and inferred phylogeny from DNA sequences of two loci, namely the internal transcribed spacer (ITS) regions and the large subunit nuclear ribosomal RNA gene (LSU), several species belonging to chalara-like genera and

  13. Coeval Eocene blooms of the freshwater fern Azolla in and around Arctic and Nordic seas

    NARCIS (Netherlands)

    Barke, J.; Burgh, A.H.P. van der; Konijnenburg-van Cittert, J.H.A. van; Collinson, M.E.; Pearce, M.A.; Bujak, J.; Heilman-Clausen, C.; Lotter, A.F.; Speelman, E.N.; Kempen, M.M.L. van; Reichart, G.-J.; Brinkhuis, H.

    2012-01-01

    For a short time interval (c. 1.2 Myr) during the early middle Eocene (~ 49 Myr), the central Arctic Ocean was episodically densely covered by the freshwater fern Azolla, implying sustained freshening of surface waters. Coeval Azolla fossils in neighboring Nordic seas were thought to have been

  14. A review of the fern genus Hypolepis (Dennstardtiaceae) in the Malesian and Pacific regions

    NARCIS (Netherlands)

    Brownsey, P.J.

    1987-01-01

    Fourteen species and one subspecies of the fern genus Hypolepis Bernh. are recognised in the Malesian and Pacific regions, excluding Australia and New Zealand. Three species, H. hawaiiensis, H. malesiana and H. scabristipes, and one subspecies, H. elegans subsp. carolinensis, are described for the

  15. Western sword fern avoids the extreme drought of 2012-2014

    Science.gov (United States)

    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...

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  18. Notes on the scholarly trajectory of Mª. Dolores Fernández-Posse

    Directory of Open Access Journals (Sweden)

    Gilman, Antonio

    2007-12-01

    Full Text Available The scholarly trajectory of Mª Dolores Fernández- Posse involved an ongoing process of critical observation, reflection, and change that is quite rare in Archaeology. Her change from normativism to a historically informed functionalism is representative of the general evolution of Spanish archaeological studies over the course of the past thirty years. What is unusual about Fernández-Posse -and attests to her straightforward and unassuming intelligence- is that she herself changed her mind and voiced that change with clarity and humor.

    La trayectoria científica de Mª Dolores Fernández-Posse se caracterizó por un proceso continuo de observación crítica, reflexión y cambio, algo poco común en Arqueología. Su cambio del normativismo a un funcionalismo de orientación histórica es representativo de la evolución de los estudios arqueológicos en España a lo largo de los últimos treinta años. Lo realmente inusual de Fernández-Posse -y lo que atestigua su directa pero no pretenciosa inteligencia- es que ella misma cambió de ideas y publicitó ese cambio con claridad y humor.

  19. New records, names and combinations of scaly tree ferns (Cyatheaceae) in eastern Malesia

    NARCIS (Netherlands)

    Coritico, F.P.; Amoroso, V.B.; Lehnert, M.

    2017-01-01

    Several scaly tree ferns (Cyatheaceae) from eastern Malesia are transferred from Cyathea s.lat. to other genera: Alsophila roroka from Sulawesi; Alsophila lamoureuxii from New Guinea; Alsophila binayana, A. bisquamata, A. mapahuwensis, A. murkelensis, A. ohaensis, and Sphaeropteris pukuana from

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

    Science.gov (United States)

    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...

  1. Population biology of two rare fern species: long-life and long-lasting stability

    Czech Academy of Sciences Publication Activity Database

    Bucharová, Anna; Münzbergová, Z.; Tájek, P.

    2010-01-01

    Roč. 97, č. 8 (2010), s. 1260-1271 ISSN 0002-9122 R&D Projects: GA MŽP SP/2D4/112/08 Institutional research plan: CEZ:AV0Z60050516 Keywords : ferns * life cycle * naturally rare species Subject RIV: EF - Botanics Impact factor: 3.052, year: 2010

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    David P Blair

    Full Text Available 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 (± 22mm/year of growth (± 1SD, with the rate increasing 5mm/yr per metre of additional height. Dicksonia antarctica averaged 33 (± 13mm/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.

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

    Science.gov (United States)

    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

  5. Isolation of polymorphic microsatellite markers and tests of cross-amplification in four widespread European calcicole ferns

    NARCIS (Netherlands)

    Groot, de G.A.; Korpelainen, H.; Wubs, E.R.J.; Erkens, R.H.J.

    2011-01-01

    Premise of the study: Studies on the biogeography and population genetics of the widespread European rock ferns Asplenium scolopendrium , A. trichomanes subsp. quadrivalens , Polystichum setiferum , and P. aculeatum would potentially yield interesting new insights into the colonization capacities of

  6. Evolution and classification of Elaphoglossum and Asplenium ferns on Cuba, and discovery of a Miocene Elaphoglossum in Dominican amber

    OpenAIRE

    Lóriga Piñero, Josmaily

    2018-01-01

    This dissertation deals with the systematics and evolution of Neotropical ferns of the genera Elaphoglossum and Asplenium, with particular focus on the species of Cuba and the West Indies. It also includes an analysis and description of an Elaphoglossum frond fragment preserved in Miocene Dominican amber. The worldwide genera Elaphoglossum with 600 species and Asplenium with 685 species are the most species-rich groups of leptosporangiate ferns. On Cuba, Elaphoglossum has 34 species and Asple...

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

    Directory of Open Access Journals (Sweden)

    Madeline R Carins Murphy

    Full Text Available 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

  8. A comparison of alpha and beta diversity patterns of ferns, bryophytes and macrolichens in tropical montane forests of southern Ecuador

    OpenAIRE

    Mandl, N A; Lehnert, M; Kessler, M; Gradstein, S R

    2010-01-01

    We present a first comparison of patterns of alpha and beta diversity of ferns, mosses, liverworts and macrolichens in neotropical montane rainforests, and explore the question whether specific taxa may be used as surrogates for others. In three localities in southern Ecuador, we surveyed terrestrial and epiphytic species assemblages in ridge and slope forests in 28 plots of 400 m² each. The epiphytic habitat was significantly richer in ferns, liverworts, and macrolichens than the terrestrial...

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

    OpenAIRE

    Sosa, Victoria; Ornelas, Juan Francisco; Ram?rez-Barahona, Santiago; G?ndara, Etelvina

    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...

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

    Science.gov (United States)

    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.

  11. Nona Fernández's Mapocho: Spirits in a Material Wasteland

    Directory of Open Access Journals (Sweden)

    Resha S Cardone

    2015-01-01

    Full Text Available This analysis of Mapocho (2002, a novel by Chilean writer and performer Nona Fernández, explores the significance of the author’s environmentalist representation of Chilean history as the accumulation of spiritual and material contaminants—ghosts and trash—that the victorious from throughout the country’s history have attempted to erase to further various economic and political agendas, particularly the neoliberal model installed during the Pinochet dictatorship. Fernández’s depiction of Chile as an ecological and spiritual wasteland in which the female protagonist (recollects, recycles and reuses the specters and detritus of past conflicts represents the author’s own literary project of advocating for human rights and environmental justice during the Chilean transition while modeling a way to counter the collective amnesia promoted under the newly established democracy.

  12. Rhizospheric metagenome of the terrestrial mangrove fern Acrostichum from Indian Sunderbans

    Directory of Open Access Journals (Sweden)

    Sayak Ganguli

    2017-12-01

    Full Text Available This study reports the analyses of the rhizospheric microbiome of the terrestrial mangrove fern Acrostichum aureum Linn. from the Indian Sunderbans. Samples were collected using standard protocols and 16S rRNA gene V3–V4 region amplicon sequencing was performed to identify the microbial communities prevalent in the rhizosphere. A total of 1,931,252 quality checked reads were assembled into 204,818 contigs and were analysed using QIIME to reveal the abundance of Proteobacteria, Acidobacteria and Planctomycetes. The data is available at the NCBI - Sequence Read Archive with accession number: SRX2660456. This is the first report of the rhizospheric microbiome belonging to a fern species.

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

    Science.gov (United States)

    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.

  14. Fern inventorization in Laiwangi-Wanggameti National Park, East Sumba, Waingapu, NTT

    Directory of Open Access Journals (Sweden)

    I NYOMAN PENENG

    2007-07-01

    Full Text Available The inventory and the collection of the ferns in Laiwangi-Wanggameti National Park will be plamted as collection plants in Bali Botanical Garden. In this research used the explorative method. The result of the research has collected 70 numbers of the ferns and 229 speciment. They consist of 21 family, 30 genus.and 70 species. From 70 species. There are 3 species such as Licopodium sernuum, Lygodium javanicum (Tumb. Sw. and Ophioglossum pendulum L. are predicted as new collection for the Bali Botanic Garden. The dominant genus in Laiwangi- Wanggameti National Park was Cyclosorus, Asplenium, Athyrium, and Pteris. Which are growing to cover the basic of the forest in damp places at the river bank.

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

    Science.gov (United States)

    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.

  16. High gene flow in epiphytic ferns despite habitat loss and fragmentation

    OpenAIRE

    Winkler, Manuela; Koch, Marcus; Hietz, Peter

    2011-01-01

    Tropical montane forests suffer from increasing fragmentation and replacement by other types of land-use such as coffee plantations. These processes are known to affect gene flow and genetic structure of plant populations. Epiphytes are particularly vulnerable because they depend on their supporting trees for their entire life-cycle. We compared population genetic structure and genetic diversity derived from AFLP markers of two epiphytic fern species differing in their ability to colonize sec...

  17. Don Andrés Bello y don José Fernández Madrid

    Directory of Open Access Journals (Sweden)

    Gabriel Giraldo Jaramillo

    1959-05-01

    Full Text Available Breve pero intensa fue la amistad de estos dos ilustres grancolombianos durante su residencia en Londres. Fernández Madrid desempeñaba el cargo de Ministro Plenipotenciario de Colombia ante el Gobierno de Su Majestad Británica y Bello estuvo por algún tiempo al frente de la secretaría de dicha misión diplomática.

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

    OpenAIRE

    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 spec...

  19. Breeding Systems of Three Tree Ferns : Alsophila firma (Cyatheaceae), Cyathea stipularis (Cyatheaceae), and Lophosoria quadripinnata (Lophosoriaceae)

    OpenAIRE

    DOUGLAS E., SOLTIS; PAMELA S., SOLTIS; ALAN R., SMITH; Department of Botany, Washington State University; Department of Botany, Washington State University; University Herbarium, University of California

    1991-01-01

    Breeding-system data have been available for a large number and diverse array of angiosperms for a relatively long time. In contrast, breeding systems of ferns and their allies (pteridophytes) have only recently been examined, and breeding-system data from natural populations of sporophytes are still lacking for pteridophytes representing many life-history strategies. Few studies, for example, have examined breeding systems of tropical pteridophytes, and no breeding-system data are available ...

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  4. The Enrichment and Transfer of Heavy Metals for Two Ferns in Pb-Zn Tailing

    Directory of Open Access Journals (Sweden)

    Mai Jiajie

    2017-01-01

    Full Text Available The enrichment and transfer of 8 heavy metals of Equisetum ramosissimum and Pteris vittata growing naturally close to edge of the sewage pool in Bencun Pb-Zn Tailing, Eastern Guangdong were investigated. The results indicated that the pollution of Cd, Pb, Hg, Zn was very severe in this tailing, followed by Cu and Mn. The potential ecological risk of heavy metals was assessed to be very strong based on soil background values of Guangdong Province and at high risk according to criteria of the second grade State Soil Environmental Quality Standard, and Cd, Hg, Pb were the main factors leading to potential ecological risk. The content of 8 heavy metals in the two ferns did not reach critical content of hyperaccumulator, so neither of them was typical hyperaccumulator, but both had a certain tolerance to these heavy metal pollution. Underground parts of Pteris vittata had an enrichment coefficient above 1 and that of Equisetum ramosissimum had a value near 1, therefore the two ferns could be utilized as potential enrichment plants. The two ferns have strong adaptability to the tailing habitat and can be used as pioneers in ecological restoration of Pb-Zn tailings.

  5. The fossil Osmundales (Royal Ferns)—a phylogenetic network analysis, revised taxonomy, and evolutionary classification of anatomically preserved trunks and rhizomes

    OpenAIRE

    Benjamin Bomfleur; Guido W. Grimm; Stephen McLoughlin

    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 exce...

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    Su Ying-Juan

    2011-04-01

    Full Text Available Abstract 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.

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

    Directory of Open Access Journals (Sweden)

    FELIPE C. NETTESHEIM

    2014-03-01

    Full Text Available 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.

  9. Relação entre a linfopenia e a persistência da papilomatose alimentar em bovinos intoxicados crônica e espontaneamente por samambaia (Pteridium aquilinum

    Directory of Open Access Journals (Sweden)

    Eduardo K Masuda

    2011-05-01

    Full Text Available Papilomavírus bovino tipo 4 (BPV-4 é responsável pelo desenvolvimento de papilomas no trato alimentar superior (TAS de bovinos. Os passos necessários para o crescimento, o desenvolvimento e a regressão dos papilomas estão intimamente relacionados com o estado imunológico do animal. A ingestão de samambaia (Pteridium aquilinum tem sido relacionada como o principal fator envolvido na persistência da infecção pelo BPV-4 no TAS. A teoria que estabelece a relação entre papilomatose alimentar e a formação de CCEs sugere a produção de um estado imunossupressivo crônico pela planta, permitindo a persistência dos papilomas no TAS. Os papilomas serviriam então como sítios de desenvolvimento dos CCEs através da interação entre as proteínas do BPV-4 e os carcinógenos da samambaia. O objetivo deste estudo foi avaliar a relação entre a quantidade de linfócitos circulantes e a papilomatose alimentar em casos de intoxicação espontânea crônica por P. aquilinum em bovinos com CCE no TAS. Quarenta bovinos com CCEs no TAS foram avaliados quanto à idade, à intensidade da papilomatose alimentar no TAS e ao leucograma. Três bovinos tinham leucopenia e um apresentava neutrofilia. A média de linfócitos foi de 5.395 (±1.696 na papilomatose leve, 4.560 (±1.561 na moderada e 5.007 (±1.786 na acentuada. Não houve diferença estatisticamente significativa entre o grau de papilomatose, a idade e a quantidade de linfócitos circulantes. Imunossupressão por linfopenia foi um achado esporádico (três casos neste estudo. Os resultados indicam que a persistência da papilomatose alimentar em casos espontâneos de intoxicação crônica por samambaia em bovinos não tem relação com a quantidade de linfócitos circulantes e que talvez esteja relacionada a outros fatores imunológicos.

  10. Global biogeography of scaly tree ferns (Cyatheaceae): evidence for Gondwanan vicariance and limited transoceanic dispersal.

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

  12. Marine Biodiversity in Juan Fernández and Desventuradas Islands, Chile: Global Endemism Hotspots.

    Science.gov (United States)

    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.

  13. Antioxidative responses to arsenic in the arsenic-hyperaccumulator Chinese brake fern (Pteris vittata L.)

    International Nuclear Information System (INIS)

    Cao Xinde; Ma, Lena Q.; Tu Cong

    2004-01-01

    This study measured antioxidative responses of Chinese brake fern (Pteris vittata L.) upon exposure to arsenic (As) of different concentrations. Chinese brake fern was grown in an artificially-contaminated soil containing 0 to 200 mg As kg -1 (Na 2 HAsO 4 ) for 12 weeks in a greenhouse. Soil As concentrations at ≤20 mg kg -1 enhanced plant growth, with 12-71% biomass increase compared to the control. Such beneficial effects were not observed at >20 mg As kg -1 . Plant As concentrations increased with soil As concentrations, with more As being accumulated in the fronds (aboveground biomass) than in the roots and with maximum frond As concentration being 4675 mg kg -1 . Arsenic uptake by Chinese brake enhanced uptake of nutrient elements K, P, Fe, Mn, and Zn except Ca and Mg, whose concentrations mostly decreased. The contents of non-enzymatic antioxidants (glutathione, acid-soluble thiol) followed similar trends as plant As concentrations, increasing with soil As concentrations, with greater contents in the fronds than in the roots especially when exposed to high As concentrations (>50 mg kg -1 ). The activities of enzymatic antioxidants (superoxide dismutase, catalase, ascorbate peroxidase, guaiacol peroxidase) in Chinese brake followed the same trends as plant biomass, increasing with soil As up to 20 mg kg -1 and then decreased. The results indicated though both enzymatic and non-enzymatic antioxidants played significant roles in As detoxification and hyperaccumulation in Chinese brake, the former is more important at low As exposure (≤20 mg kg -1 ), whereas the latter is more critical at high As exposure (50-200 mg kg -1 ). - At low levels of arsenic exposure, enzymatic antioxidants are important for arsenic detoxification and accumulation in Chinese brake fern, while non-enzymatic antioxidants were more important at high arsenic exposure

  14. Marine Biodiversity in Juan Fernández and Desventuradas Islands, Chile: Global Endemism Hotspots

    Science.gov (United States)

    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

  15. Edge effects on understory epiphytic ferns and epiphyllous bryophytes in moist afromontane forests of Ethiopia

    Directory of Open Access Journals (Sweden)

    Hylander Kristoffer

    2013-12-01

    Full Text Available Most studies on edge effects in tropical forests have been conducted in landscapes with low human population density and in situations where the edges have been left unused after logging of the adjacent area. Here we studied forest margins heavily used by local farmers in a forest/agriculture mosaic landscape in Ethiopia. We compared forest structure and plant species composition across 41 forest-agriculture ecotones from 200 m out into the agricultural area to 200 m into the forest. There are strong edge effects from the edge and into the forest on canopy cover and number of stumps and apparently these forest-agricultural edges are intensively used by humans. They are penetrated by paths, beehives are found in the trees, timber of various dimensions is harvested and there is sometimes substantial cover of perennial wild (or semi-wild crops such as coffee and spices. The number of understory epiphytic fern species as well as number of epiphyllous (i.e., growing on leaves bryophyte species was lower at 20 m than at 75 m from the edge. The number of fern species was higher in newly created edges and thereafter they declined, which indicates an extinction debt. This pattern was not seen for the epiphyllous bryophytes. It is likely that different human management activities are responsible for many of the found edge effects besides wind and sun effects from the edge. Tropical forest margins provide important resources for people in many landscapes. It is important to understand how such use affects the biota of the forests. This study shows that there are substantial edge effects, but that the edge effects do not seem to become worse over time for epiphyllous bryophytes and only slightly so for ferns.

  16. Continental scale patterns and predictors of fern richness and phylogenetic diversity

    Directory of Open Access Journals (Sweden)

    Nathalie eNagalingum

    2015-04-01

    Full Text Available Because ferns have a wide range of habitat preferences and are widely distributed, they are an ideal group for understanding how diversity is distributed. Here we examine fern diversity on a broad-scale using standard and corrected richness measures as well as phylogenetic indices; in addition we determine the environmental predictors of each diversity metric. Using the combined records of Australian herbaria, a dataset of over 60,000 records was obtained for 89 genera to infer richness. A phylogenetic tree of all the genera was constructed and combined with the herbarium records to obtain phylogenetic diversity patterns. A hotspot of both taxic and phylogenetic diversity occurs in the Wet Tropics of northeastern Australia. Although considerable diversity is distributed along the eastern coast, some important regions of diversity are identified only after sample-standardization of richness and through the phylogenetic metric. Of all of the metrics, annual precipitation was identified as the most explanatory variable, in part, in agreement with global and regional fern studies. Precipitation was combined with a different variable for each different metric. For corrected richness, precipitation is combined with temperature seasonality, while correlation of phylogenetic diversity to precipitation plus radiation indicates support for the species-energy hypothesis. Significantly high and significantly low phylogenetic diversity were found in geographically separate areas. These areas are correlated with different climatic conditions such as seasonality in precipitation. The use of phylogenetic metrics identifies additional areas of significant diversity, some of which have not been revealed using traditional taxonomic analyses, suggesting that different ecological and evolutionary processes have operated over the continent. Our study demonstrates that it is possible and vital to incorporate evolutionary metrics when inferring biodiversity hotspots

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

    Directory of Open Access Journals (Sweden)

    Ting Wang

    Full Text Available BACKGROUND: 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. METHODOLOGY/PRINCIPAL FINDINGS: 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. CONCLUSIONS/SIGNIFICANCE: 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.

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

    Science.gov (United States)

    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

  19. CLASSICAL AND ROMANTIC FEATURES IN BEETHOVEN’S SONG CYCLE AN DIE FERNE GELIEBTE

    Directory of Open Access Journals (Sweden)

    TUREA ELENA

    2016-12-01

    Full Text Available This article examines the cycle of songs An die ferne Geliebte written by Beethoven in 1816 as the fi rst example of a vocal cycle in the history of music. It is investigated in terms of correlation between the classical and romantic features pursued both in the content and structural aspect. It features the presentiment of the romantic lied in the musical language and development principles of the thematic material, in morphogenesis. Th e semantic correlations between the cycle numbers and the melodicrhythmic ties are highlighted, special emphasis is laid on the piano part in the dramaturgy of the whole.

  20. Absorption of foliar-applied arsenic by the arsenic hyperaccumulating fern (Pteris vittata L.)

    Energy Technology Data Exchange (ETDEWEB)

    Bondada, Bhaskar R.; Tu, Shuxin; Ma, Lena Q

    2004-10-01

    The fact that heavy metals can enter various domains of the plant system through foliar pathways spurred us to explore if the fronds of the Chinese brake fern (Pteris vittata L.), a hyperaccumulator of arsenic, a carcinogenic metalloid, was proficient in absorbing arsenic in the form of sprays. The specific objective of this study was to investigate the impact of frond age, form of arsenic, and time of application on the absorption of foliar-applied arsenic by the brake fern; also examined were the effects of foliar sprays on surface ultrastructure and arsenic speciation in the frond following absorption. Foliar sprays of different arsenic concentrations (0, 50, 100, 200, and 400 ppm) were applied to young and fertile fronds. A positive linear relationship existed between arsenic concentration and absorption; the arsenic concentration of fronds increased from 50 to 200 ppm. Time-course analysis with excised pinnae indicated an initial linear increase followed by a plateau at 48 h. The young fronds with immature sori absorbed more arsenic (3100 ppm) than the fertile mature fronds (890 ppm). In the frond, the arsenic absorption was greatest in the lamina of the pinnae followed by the sori and the rachis. Applying arsenic during night (20:00-22:00 h) or afternoon (12:00-14:00 h) resulted in greater absorption of arsenic than the application in the morning (08:00-10:00 h). The arsenic absorption was greater through abaxial surfaces than through adaxial surfaces. The brake fern absorbed more arsenic when it was applied in the form of arsenite. Regardless of the form of arsenic and the surface it was applied to, arsenic occurred as arsenite, the reduced and the most toxic form of arsenic, after having been absorbed by the fronds. Scanning electron microscopy revealed no surface morphological alterations following all arsenic sprays. The study unequivocally illustrated that the Chinese brake fern absorbed foliar-applied arsenic with great efficiency. Consequently, the

  1. Absorption of foliar-applied arsenic by the arsenic hyperaccumulating fern (Pteris vittata L.)

    International Nuclear Information System (INIS)

    Bondada, Bhaskar R.; Tu, Shuxin; Ma, Lena Q.

    2004-01-01

    The fact that heavy metals can enter various domains of the plant system through foliar pathways spurred us to explore if the fronds of the Chinese brake fern (Pteris vittata L.), a hyperaccumulator of arsenic, a carcinogenic metalloid, was proficient in absorbing arsenic in the form of sprays. The specific objective of this study was to investigate the impact of frond age, form of arsenic, and time of application on the absorption of foliar-applied arsenic by the brake fern; also examined were the effects of foliar sprays on surface ultrastructure and arsenic speciation in the frond following absorption. Foliar sprays of different arsenic concentrations (0, 50, 100, 200, and 400 ppm) were applied to young and fertile fronds. A positive linear relationship existed between arsenic concentration and absorption; the arsenic concentration of fronds increased from 50 to 200 ppm. Time-course analysis with excised pinnae indicated an initial linear increase followed by a plateau at 48 h. The young fronds with immature sori absorbed more arsenic (3100 ppm) than the fertile mature fronds (890 ppm). In the frond, the arsenic absorption was greatest in the lamina of the pinnae followed by the sori and the rachis. Applying arsenic during night (20:00-22:00 h) or afternoon (12:00-14:00 h) resulted in greater absorption of arsenic than the application in the morning (08:00-10:00 h). The arsenic absorption was greater through abaxial surfaces than through adaxial surfaces. The brake fern absorbed more arsenic when it was applied in the form of arsenite. Regardless of the form of arsenic and the surface it was applied to, arsenic occurred as arsenite, the reduced and the most toxic form of arsenic, after having been absorbed by the fronds. Scanning electron microscopy revealed no surface morphological alterations following all arsenic sprays. The study unequivocally illustrated that the Chinese brake fern absorbed foliar-applied arsenic with great efficiency. Consequently, the

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

    Science.gov (United States)

    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...

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

  5. The physiological resilience of fern sporophytes and gametophytes: advances in water relations offer new insights into an old lineage

    Directory of Open Access Journals (Sweden)

    Jarmila ePittermann

    2013-08-01

    Full Text Available Ferns are some of the oldest vascular plants in existence and they are the second most diverse lineage of tracheophytes next to angiosperms. Recent efforts to understand fern success have fo-cused on the physiological capacity and stress tolerance of both the sporophyte and the gameto-phyte generations. In this review, we examine these insights through the lens of plant water rela-tions, focusing primarily on the form and function of xylem tissue in the sporophyte, as well as the tolerance to and recovery from drought and desiccation stress in both stages of the fern life cycle. The absence of secondary xylem in ferns is compensated by selection for efficient primary xylem composed of large, closely arranged tracheids with permeable pit membranes. Protection from drought-induced hydraulic failure appears to arise from a combination of pit membrane traits and the arrangement of vascular bundles. Features such as tracheid-based xylem and vari-ously sized megaphylls are shared between ferns and more derived lineages, and offer an oppor-tunity to compare convergent and divergent hydraulic strategies critical to the success of xylem-bearing plants. Fern gametophytes show a high degree of desiccation tolerance but new evidence shows that morphological attributes in the gametophytes may facilitate water retention, though little work has addressed the ecological significance of this variation. We conclude with an emergent hypothesis that selection acted on the physiology of both the sporophyte and gameto-phyte generations in a synchronous manner that is consistent with selection for drought tolerance in the epiphytic niche, and the increasingly diverse habitats of the mid to late Cenozoic.

  6. Plants that can be Poisonous for Cows. A Review

    Directory of Open Access Journals (Sweden)

    Cristina EL MAHDY

    2017-11-01

    Full Text Available Romania is blessed with a rich spontaneous flora, but some of the plants are toxic by their consumption in cattle, affecting the health, productions and endangering consumer safety. Sometimes even the consumption of small amounts causes poisoning with a broad extension: from mild, moderate to severe and with chronic or acute manifestations. Plant action is not similar. Taxus Buccata, Eupatorium spp. (E. rugosum, E. urticaefolium, E. ogeratoides are cardiotoxic plants, but, Eupatorium spp. also acts through depression of the central nervous system; Datura stramonium (Jimson weed, Solanum spp. (nightshades, Atropa belladonna (belladonna, are plants with cholinergic blocking; haemolytic anemia is caused by Pteridium aquilinum (Bracken fern and Equisetum (horsetail. The poisoning with cyanogenic principles occurs at Sorghum spp (Johnson grass, sudan grass; Elderberry consumption, Senecio spp. and Hypericum (St John’s wort induces liver toxicity. Plants containing alkaloids outside their toxicity also have teratogenic action: Lupinus spp., Nicotiana spp, Conium maculatum, Veratrum album. However, some of these plants can be used in certain cows’ treatments.

  7. Concentration factors and aggregated transfer factors in selected bio-indicators from Sweden[Radioecology

    Energy Technology Data Exchange (ETDEWEB)

    Holm, E.; Samuelsson, C.; Holstensson, M. [Lund Univ. (Sweden)

    2006-04-15

    Previously most common has been to use lichens and mosses in the terrestrial environment and mussels and algae in the marine environment. Several plants are promising and less commonly used such as ferns (e.g. Bracken, Pteridium aquilinum) and the fresh water plant, Water horsetail (Equisetum fluviatile). These show high uptake of radiocaesium but also accumulate plutonium and americium. Even if the uptake of transuranic elements is low, this behaviour is rather unique for plants. On bases of available data we have calculated concentration factors Cf and aggregated transfer factors, ATF according to their definitions i.e. Bq kg{sup -1} (biota)/Bq kg{sup -1}(water) and Bq kg{sup -1} (biota)/Bq m{sup -2} respectively. For earlier samples the water concentrations can only roughly be estimated while deposition data are rather well known. For fresh water samples it is a little awkward to use concentration factors since the uptake generally is not from water. Therefore a kind of Aggregated Transfer Factor has also been calculated on basis of using the same areal deposition in sediments as on land. We have used dry weight concentrations for biota. Data are presented for samples of various bio-medicator organisms. (LN)

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  10. Abrupt deceleration of molecular evolution linked to the origin of arborescence in ferns.

    Science.gov (United States)

    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.

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

    International Nuclear Information System (INIS)

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

    2009-01-01

    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. - This paper presents a predictive model for phytoremediation of soils, historically contaminated with arsenic, by the hyperaccumulator P. vittata.

  12. Mutation induction of blechnum gibium a fern species through in vitro propagation

    International Nuclear Information System (INIS)

    Azhar Mohamad; Amran Abd Halim; Rusli Ibrahim

    2002-01-01

    Blechnum gibum is a fern with beutiful symmetry and unique palm-like appearance. Mutation induction is an alternative way to increase its variability in characteristics. Information on the radiosensitivity test is an important factor in deciding the approach to be taken for genetic changes of the fern in mutation breeding. Plantlets of B. gibum were irradiated with doses of 0, 10, 20, 40, 60, 80, 100 and 150 Gy using a gamma cell with a 60 Co source at dose rate of 0.25 Gy s -1 . . Irradiated plantlets were cultured on semi solid modified hormone free Murashige and Skoog (MS) media and incubated at 24 degree C with a photoperiod of 16 hours (3500 lux). Radiosensitivity was assessed by the survival rate 7 weeks after the treatment. Increasing gamma ray doses caused a reduction of survival rate as well as the number of fronds produced per plantlet. LD 50 for B. gibum was 54 Gy as estimated from the dose rate vs survival curve. Regenerated plantlets from treated plantlets showed a stunted and slow recovery growth especially for higher doses as compared to control plantlets. (Author)

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

    Energy Technology Data Exchange (ETDEWEB)

    Nurnida, M. K., E-mail: nurnidakamal@gmail.com; Noraini, T.; Ruzi, A. R.; Idris, S. [School of Environmental and Natural Resource Sciences Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor (Malaysia)

    2015-09-25

    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 presence 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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Shelmerdine, Paula A.; Black, Colin R. [School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough LE12 5RD (United Kingdom); McGrath, Steve P. [Rothamsted Research, Harpenden, Herts AL5 2JQ (United Kingdom); Young, Scott D., E-mail: scott.young@nottingham.ac.u [School of Biosciences, Biology Building, University of Nottingham, University Park, Nottingham NG7 2RD (United Kingdom)

    2009-05-15

    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 {sup 73}As{sup 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. - This paper presents a predictive model for phytoremediation of soils, historically contaminated with arsenic, by the hyperaccumulator P. vittata.

  15. El blocao (y el bloqueo de José Díaz Fernández

    Directory of Open Access Journals (Sweden)

    Luis Fernando Bueno Morillas

    2015-06-01

    Full Text Available El blocao (1928 fue la primera novela de José Díaz Fernández. Supuso un éxito editorial insólito hasta entonces porque reunía tres características novedosas: una actitud crítica ante la guerra de Marruecos, una integración de las novedades vanguardistas en la que su autor llamó literatura de avanzada y un posicionamiento del intelectual al lado de las reivindicaciones del pueblo. Sin embargo, aunque publicó otra novela un año después (La Venus mecánica, un libro teórico en el que definía la literatura que él propugnaba y practicaba (El nuevo romanticismo y algunas narraciones breves, Díaz Fernández se bloqueó y dejó la literatura narrativa que tan buenas expectativas levantó. Analizaremos las posibles causas de ese bloqueo.

  16. Ceratopteris richardii (C-fern: A model for investigating adaptive modification of vascular plant cell walls

    Directory of Open Access Journals (Sweden)

    Olivier eLeroux

    2013-09-01

    Full Text Available Plant cell walls are essential for most aspects of plant growth, development, and survival, including cell division, expansive cell growth, cell-cell communication, biomechanical properties, and stress responses. Therefore, characterising cell wall diversity contributes to our overall understanding of plant evolution and development. Recent biochemical analyses, concomitantly with whole genome sequencing of plants located at pivotal points in plant phylogeny, have helped distinguish between homologous characters and those which might be more derived. Most plant lineages now have at least one fully sequenced representative and although genome sequences for fern species are in progress they not yet available this group. Ferns offer key advantages for the study of developmental processes leading to vascularisation and complex organs as well as the specific differences between diploid sporophyte tissues and haploid gametophyte tissues and the interplay between them. Ceratopteris richardii has been well investigated building a body of knowledge which combined with the genomic and biochemical information available for other plants will progress our understanding of wall diversity and its impact on evolution and development.

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

    Science.gov (United States)

    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.

  18. The freshwater fern Azolla (Azollaceae) from Eocene Arctic and Nordic Sea sediments: New species and their stratigraphic distribution

    NARCIS (Netherlands)

    van der Burgh, J.; Collinson, M.E.; van Konijnenburg-van Cittert, J.H.A.; Barke, J.; Brinkhuis, H.

    2013-01-01

    Three new species of the freshwater fern Azolla are described from Eocene marine deposits of the Arctic and Nordic seas, bringing the total number of species now documented from these areas to five. Azolla arctica Collinson et al., Azolla jutlandica Collinson et al., Azolla nova sp. nov. and Azolla

  19. Macrobenthos of Vembanad estuary in relation to the deposition of degraded water fern Salvinia and other macrophytes

    Digital Repository Service at National Institute of Oceanography (India)

    Gopalan, U.K.; Meenakshikunjamma, P.P.; Vengayil, D.T.

    Composition and seasonal abundance of macrobenthos in Vembanad estuary (India) seems to be influenced by the density of decaying macrophytes, especially the water fern Salvinia , deposited at the bottom of the estuary at the rate of 356.76 g/m super...

  20. Epiphytic ferns in swamp forest remnants of the coastal plain of southern Brazil: latitudinal effects on the plant community

    Directory of Open Access Journals (Sweden)

    Letícia S. Machado

    Full Text Available ABSTRACT Community structure and spatial distribution of epiphytic ferns in swamp forest remnants along the coastal plain of the state of Rio Grande do Sul were analyzed. A total of 440 trees were sampled in fifty-seven 10 x 10 m plots. Each phorophyte was divided into five ecological zones (strata, where all species of epiphytic ferns were recorded. A total of 34 species representing 18 genera in six families were recorded. Polypodiaceae was the most represented family with 17 species, and Microgramma vacciniifolia had the highest epiphytic importance value. Characteristic holoepiphyte was the predominant ecological category, representing 70 % of the species. Ordination analysis showed a gradual change in floristic composition between ecological zones with richness differing significantly between strata. We observed that with increasing latitude there was a decrease in mean temperature and total rainfall, but an increase in frosts. These climatic and phytogeography changes result in a reduction in species richness and a change in the structure of epiphytic fern communities in a north-to-south direction. The importance of swamp forest remnants of the coastal plain to the diversity of epiphytic ferns is discussed.

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

    Directory of Open Access Journals (Sweden)

    JL. Schmitt

    Full Text Available 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.

  2. Antibacterial activity of the terrestrial fern Lygodium flexuosum (L. Sw. against multidrug resistant enteric- and uro-pathogenic bacteria

    Directory of Open Access Journals (Sweden)

    Nabakishore Nayak

    2013-01-01

    Conclusions: Phytochemical analysis of the water-extract of L. flexuosum confirmed the presence of glycosides and carbohydrates, but alkaloids, terpenoids, steroids, saponins, tannins, and flavonoids were absent. L. flexuosum, being a fern, is a suitable non-microbial source of antimicrobial for MDR strains of major enteric and uro-pathogens.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

  5. ANATOMICAL-HISTOLOGICAL OBSERVATIONS CONDUCTED ON AQUATIC FERNS IN THE DANUBE DELTA

    Directory of Open Access Journals (Sweden)

    Anca SÂRBU

    2017-12-01

    Full Text Available This paper analyses aquatic ferns from the genera Azolla Lam., Marsilea L. and Salvinia Séguier, which occur in the Danube Delta, Romania, and comprises a series of anatomical and histological observations of taxonomical, chorological and eco-morphological importance. The research conducted on specimens collected between 2005-2013 from the natural habitats of the Danube Delta, but also from the extra-deltaic artificial habitats have enabled: i a reconsideration of some chorological aspects regarding the species of the genus Azolla in Romania; ii a greater understanding of the adaptive plasticity relative to the factor water for the taxon Marsilea quadrifolia L. collected from natural and artificial habitats; iii the enrichment of the data regarding the structural characteristics of the taxon Salvinia natans (L. All., particularly around the adaptive elements associated with living on the surface of the water.

  6. Development and characterization of 27 microsatellite markers for the mangrove fern, Acrostichum aureum (Pteridaceae).

    Science.gov (United States)

    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.

  7. Role of glutathione in tolerance to arsenite in Salvinia molesta, an aquatic fern

    Directory of Open Access Journals (Sweden)

    Adinan Alves da Silva

    2017-09-01

    Full Text Available ABSTRACT In many plant species, tolerance to toxic metals is highly dependent on glutathione, an essential metabolite for cellular detoxification. We evaluated the responses of glutathione metabolism to arsenite (AsIII in Salvinia molesta, an aquatic fern that has unexplored phytoremediation potential. Plants were exposed to different AsIII concentrations in nutrient solution for 24 h. AsIII caused cell membrane damage to submerged leaves, indicating oxidative stress. There was an increase in the glutathione content and ϒ-glutamylcysteine synthetase enzyme activity in the submerged and floating leaves. The glutathione peroxidase and glutathione sulfotransferase enzymes also showed increased activity in both plant parts, whereas glutathione reductase only showed increased activity in the submerged leaves. These findings suggest an important role for glutathione in the protection of S. molesta against the toxic effects of AsIII, with more effective tolerance responses in the floating leaves.

  8. Toxicity of Diclofenac in the Fern Azolla filiculoides and the Lichen Xanthoria parietina.

    Science.gov (United States)

    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.

  9. REE bound proteins in natural plant fern Dicranopteris dichitoma by MAA

    International Nuclear Information System (INIS)

    Guo, F.Q.; Wang, Y.Q.; Sun, J.X.; Chen, H.M.

    1996-01-01

    Biochemical techniques, including pH variation, outsalting, ultracentrifugation, gel filtration chromatography and electrophoresis, etc., have been employed together with instrumental neutron activation analysis (INAA) to study the rare earth elements (REE) bound proteins in the natural plant fern, Dicranopteris dichitoma. INAA was also used to identify whether the proteins were bound firmly with REE. The results obtained show that two REE bound proteins (RBP-I and RBP-II) have been separated. The molecular weight of RBP-I on Sephadex G-200 gel column is about 8 x 10 5 Daltons and that of RBP-II is less than 12,400 Daltons, respectively. However, SDS-PAGE of the two proteins shows that they mainly have two protein subunits with MW 14,100 and 38,700 Daltons. They are probably conjugated proteins, glycoproteins with different glyco-units. (author). 22 refs., 7 figs., 1 tab

  10. Study on REE bound proteins in natural plant fern dicranopteris dichotomy by MAA

    International Nuclear Information System (INIS)

    Guo Fanqing; Wang Yuqi; Sun Jingxing; Chen Hongmin; Xu Lei; Cao Guoyin

    1997-01-01

    Biochemical techniques, including pH variation, outsalting, ultracentrifugation, gel filtration chromatography and electrophoresis, etc., have been employed together with instrumental neutron activation analysis (INAA) to study the rare earth elements (REE) bound proteins in the natural plant fern, Dicranopteris dichotomy. INAA was also used to identify whether the proteins were bound firmly with REE. The results obtained show that two REE bound proteins (RBP-I and RBP-II) have been separated. The molecular mass (molecular weight, MW) of RBP-I on Sephadex G-200 gel column is about 8 x 10 5 and that of RBP-II is less than 12400, respectively. However, SDS-PAGE of the two proteins shows that they mainly have two protein subunits with MW 14100 and 38700. They are probably conjugated proteins, glycoproteins with different glycol-units

  11. Transgressive intimacy in the fiction of Costamagna, Fernández, Jeftanovic, Maturana and Meruane

    Directory of Open Access Journals (Sweden)

    Nan Zheng

    2017-11-01

    Full Text Available The present work, framed primarily in the discourse of intimacy, Jacques Rancière’s theory of the aesthetic regime of art and Wendy Brow's revision of Foucault's reflecctions on Neoliberalism, examines the chilean fictions of the last two decades by Alejandra Costamagna, Nona Fernández, Andrea Jeftanovic, Andrea Maturana and Lina Meruane. The literary production of these female writers disagrees with patriarchal norms and those established by the neoliberal rationality dominated by the homo oeconomicus. This article analyzes the possibility of classifying these writers as a new literary generation of the post-dictatorship, which could be more inconvenient than benefical, since it would represent a gesture which could be establishing divisions between feminine and masculine; private and public; the sublime in art and the banality of everyday life.

  12. Arsenic speciation for the phytoremediation by the Chinese brake fern, Pteris vittata.

    Science.gov (United States)

    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.

  13. Cryopreservation of spores of Dicksonia sellowiana: an endangered tree fern indigenous to South and Central America.

    Science.gov (United States)

    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

  14. The reversion phenomenon in irradiated fern prothalli: Effects of acute or chronic anoxia and let

    International Nuclear Information System (INIS)

    Hendry, J.H.; Cowie, F.G.; Wangenheim, K.H. von

    1985-01-01

    In several systems a paradoxical reduction of radiation damage with increasing dose, termed reversion, has been observed. In the fern Osmunda regalis the percentage of cells which does not die but stays alive, although reproductively sterile, increases with dose. The assumed mechanism of this effect is a continuation of cytoplasmic growth during radiation-induced mitotic delay which induces terminal differentiation (early differentiation) thus preventing mitosis and the expression of chromosomal injury. Suppression of cytoplasmic growth after irradiation should abrogate reversion. This was tested using anoxia. Reversion was suppressed by storage of the sporelings in nitrogen for 8 h or more after X-rays, but was not suppressed by storage in 0.27 μM oxygen nor by a 60-min exposure to air after irradiation and before storage in nitrogen. Anoxia before irradiation in air had no effect.

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

    Directory of Open Access Journals (Sweden)

    Victoria Sosa

    2016-11-01

    Full Text Available 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

  16. Is there foul play in the leaf pocket? The metagenome of floating fern Azolla reveals endophytes that do not fix N2but may denitrify

    NARCIS (Netherlands)

    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 P.M.; 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

  17. Water ferns Azolla spp. (Azollaceae as new host plants for the small China-mark moth, Cataclysta lemnata (Linnaeus, 1758 (Lepidoptera, Crambidae, Acentropinae

    Directory of Open Access Journals (Sweden)

    Atousa Farahpour-Haghani

    2017-01-01

    Full Text Available Water ferns (Azolla spp., Azollaceae are reported for the first time as host plants for the larvae of the small China-mark moth Cataclysta lemnata (Linnaeus (Lepidoptera: Crambidae: Acentropinae in rice fields and waterways of northern Iran. Cataclysta lemnata is a semi-aquatic species that has been recorded to feed on Lemnaceae and a few other aquatic plants. However, it has not been reported before on Azolla spp. Larvae use water fern as food source and shelter and, at high population density in the laboratory, they completely wiped water fern from the water surface. Feeding was confirmed after rearing more than eight continual generations of C. lemnata on water fern in the laboratory. Adults obtained this way are darker and have darker fuscous markings in both sexes compared with specimens previously reported and the pattern remains unchanged after several generations.

  18. Bioaccumulation of selected heavy metals by the water fern, Azolla filiculoides Lam. in a wetland ecosystem affected by sewage, mine and industrial pollution

    Energy Technology Data Exchange (ETDEWEB)

    Wet, L.P.D. de; Schoonbee, H.J.; Pretorius, J.; Bezuidenhout, L.M. (Rand Afrikaans University, Johannesburg (South Africa). Depts. of Zoology and Botany, Research Unit for Aquatic and Terrestrial Ecosystems)

    1990-10-01

    The bio-accumulation of the heavy metals, Fe, Cu, Ni, Pb, Zn, Mn and Cr by the water fern, Azolla filiculoides Lam. in a wetland ecosystem polluted by effluents from sewage works, mines and industries was investigated. Results showed that the different metals can be accumulated by the water fern at concentration levels not necessarily related to their actual concentrations in the aquatic environment, as measured in this case, in the bottom sediments. 45 refs., 1 fig., 3 tabs.

  19. 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.

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    Nick Dexter

    Full Text Available 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

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

  3. Towards a Discourse about the City in the New World: the Example of Gonzalo Fernández de Oviedo

    Directory of Open Access Journals (Sweden)

    Álvaro Baraibar

    2017-11-01

    Full Text Available This paper aims to be an initial approach to the way in which Gonzalo Fernández de Oviedo puts up an specific discourse in his work at the time of describing the American city. Concretely, I have been interested in analyzing the ways the first chronicler of the American Indies adapts long-time used formulas from the old continent when he is introducing the reader to the new reality constituted by the American city. That is the case of Santo Domingo, a city to which Gonzalo Fernández de Oviedo was especially bounded. It will serve us as an example to study how the chronicler adapts the formula of the panegyric of the city to the New World.

  4. Strong congruence in tree and fern community turnover in response to soils and climate in central Panama

    DEFF Research Database (Denmark)

    Jones, Mirkka; Ferrier, Simon; Condit, Richard

    2013-01-01

    1. Plant species turnover in central Panamanian forests has been principally attributed to the effects of dispersal limitation and a strong Caribbean to Pacific gradient in rainfall seasonality. Despite marked geological heterogeneity, the role of soil variation has not been rigorously examined. 2....... We modelled the compositional turnover of trees and ferns in the Panama Canal watershed as a function of soil chemistry, climate and geographical separation, using generalized dissimilarity models (GDMs). 3. Predictability in both plant groups was strong, with 74% of turnover explained in trees...... and 49% in ferns. Major trends in the two plant groups were strikingly similar. The independent effects of soils, and of climate for trees, were sizeable, but those of geographical distance were minor. In both plant groups, distance and climatic effects on species turnover covaried strongly. 4. Including...

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

    Science.gov (United States)

    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 Azolla in paddy fields to reduce As transfer from soil and water to rice should be further evaluated.

  6. Cyathea arjae Latiff (Cyatheaceae), A New Species of Dwarf Tree-Fern from Sayap, Mt. Kinabalu, Sabah, Malaysia

    International Nuclear Information System (INIS)

    Latiff, A.

    2015-01-01

    A dwarf tree-fern, Cyathea arjae Latiff is described as a new species from Sayap, Mt. Kinabalu, Sabah, Malaysia. This new species belongs to Schizocaena group which has basiscopic veins that originate from the costa and not from the costule. It is closely related to C. capitata in having simply pinnate fronds of which the apex is a deltoid lamina. Holttums key was modified. (author)

  7. Photoproduction of hydrogen by a non-sulphur bacterium isolated from root zones of water fern Azolla pinnata

    Energy Technology Data Exchange (ETDEWEB)

    Singh, S.P.; Srivastava, S.C.; Pandey, K.D. (Banaras Hindu Univ., Varanasi (IN). Centre of Advanced Study in Botany)

    1990-01-01

    A photosynthetic bacterium Rhodopseudomonas sp. BHU strain 1 was isolated from the root zone of water fern Azolla pinnata. The bacterium was found to produce hydrogen with potato starch under phototrophic conditions. The immobilized bacterial cells showed sustained hydrogen production with a more than 4-fold difference over free cell suspensions. The data have been discussed in the light of possible utilization of relatively cheaper raw materials by non-sulphur bacteria to evolve hydrogen. (author).

  8. Vestigios de Alvar Aalto en la opera prima de Antonio Fernández Alba (1959-62

    Directory of Open Access Journals (Sweden)

    Lucía C. Pérez-Moreno

    2018-04-01

    Full Text Available La obra de Antonio Fernández Alba de los años sesenta ha sido fundamentalmente calificada de orgánica aludiendo a sus consonancias con la arquitectura de Alvar Aalto. Este texto ahonda en la lectura que Fernández Alba presentó sobre la cultura finesa en varios escritos publicados en la revista madrileña Arquitectura, entre los que destaca el ensayo “Valores humanos y estéticos en el diseño finlandés” publicado en 1962. Reflexiones presentadas en este texto tomaron forma en el colegio Nuestra Señora Santa María en Madrid, un proyecto en el que Fernández Alba estaba trabajando en estos mismos años. Sin eludir la condición de colegio católico y femenino del proyecto, se reflexiona en torno a decisiones proyectuales que ponen de manifestó el interés de Fernández Alba por ofrecer a las niñas educadas en sus espacios una arquitectura propicia para el juego, conectada con la naturaleza circundante, no regida por formas preconcebidas, amable en la elección de sus materiales y libre en el uso y disfrute de sus dependencias. En definitiva, una arquitectura que tuvo en cuenta las necesidades psicofísicas de alumnas y profesorado o una arquitectura humanizada, aludiendo al conocido ensayo de Alvar Aalto escrito en 1940.

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

    Science.gov (United States)

    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.

  10. Antibacterial activity of the terrestrial fern Lygodium flexuosum (L.) Sw. against multidrug resistant enteric- and uro-pathogenic bacteria

    OpenAIRE

    Nabakishore Nayak; Sibanarayan Rath; Monali P. Mishra; Goutam Ghosh; Rabindra N. Padhy

    2013-01-01

    Objective: To investigate antibacterial properties of the terrestrial fern Lygodium flexuosum (L. flexuosum) obtained from Kalahandi district, Odisha against enteric- and uro-pathogenic bacteria isolated from clinical samples. Methods: Frond-extracts of L. flexuosum were obtained by the cold percolation method using four solvents, petroleum ether, chloroform, methanol and water. Antibacterial potencies of concentrated cold frond-extracts were tested by the agar-well diffusion method agains...

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

    OpenAIRE

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

    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 c...

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Xin [State Key Lab of Urban and ONAL Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085 (China); Lin Aijun [Department of Environmental Science and Engineering, Beijing University of Chemical Technology, Beijing 100029 (China); Zhao Fangjie [Soil Science Department, Rothamsted Research, Hertfordshire AL5 2JQ (United Kingdom); Xu Guozhong [Agricultural Ecology Institute, Fujian Academy of Agricultural Sciences, Fuzhou 350013 (China); Duan Guilan [State Key Lab of Urban and ONAL Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085 (China); Zhu Yongguan [State Key Lab of Urban and ONAL Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085 (China); Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361003 (China)], E-mail: ygzhu@rcees.ac.cn

    2008-12-15

    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 methlyated 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. - Arsenic accumulation and efflux differ between strains of the aquatic fern Azolla.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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).

  17. Inorganic and organic nitrogen acquisition by a fern Dicranopteris dichotoma in a subtropical forest in South China.

    Directory of Open Access Journals (Sweden)

    Xingliang Xu

    Full Text Available The fern Dicranopteris dichotoma is an important pioneer species of the understory in Masson pine (Pinus massoniana forests growing on acidic soils in the subtropical and tropical China. To improve our understanding of the role of D. dichotoma in nitrogen (N uptake of these forests, a short-term (15N experiment was conducted at mountain ridge (MR, with low N level and mountain foot (MF, with high N level. We injected (15N tracers as (15NH4, (15NO3 or (15N-glycine into the soil surrounding each plant at both MR and MF sites. Three hours after tracer injection, the fern D. dichotoma took up 15NH4+ significantly faster at MF than at MR, but it showed significantly slower uptake of (15NO3- at MF than at MR. Consequently, (15NO3- made greater contribution to the total N uptake (50% to the total N uptake at MR than at MF, but (15N-glycine only contributed around 11% at both sites. Twenty-four hours after tracer injection, D. dichotoma preferred (15NH4+ (63% at MR, whereas it preferred (15NO3- (47% at MF. We concluded that the D. dichotoma responds distinctly in its uptake pattern for three available N species over temporal and spatial scales, but mainly relies on inorganic N species in the subtropical forest. This suggests that the fern employs different strategies to acquire available N which depends on N levels and time.

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

    Directory of Open Access Journals (Sweden)

    Irene de Araújo Barros

    2010-12-01

    Full Text Available 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.

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

    Science.gov (United States)

    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.

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

    International Nuclear Information System (INIS)

    Zhang Xin; Lin Aijun; Zhao Fangjie; Xu Guozhong; Duan Guilan; Zhu Yongguan

    2008-01-01

    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 methlyated 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. - Arsenic accumulation and efflux differ between strains of the aquatic fern Azolla

  1. Identification and Characterization of TALE Homeobox Genes in the Endangered Fern Vandenboschia speciosa.

    Science.gov (United States)

    Ruiz-Estévez, Mercedes; Bakkali, Mohammed; Martín-Blázquez, Rubén; Garrido-Ramos, Manuel A

    2017-10-17

    We report and discuss the results of a quantitative reverse transcription polymerase chain reaction (qRT-PCR) analysis of the expression patterns of seven three amino acid loop extension ( TALE ) homeobox genes (four KNOTTED-like homeobox ( KNOX ) and three BEL1-like homeobox ( BELL ) genes) identified after next generation sequencing (NGS) and assembly of the sporophyte and gametophyte transcriptomes of the endangered fern species Vandenboschia speciosa . Among the four KNOX genes, two belonged to the KNOX1 class and the other two belonged to the KNOX2 class. Analysis of the deduced amino acid sequences supported the typical domain structure of both types of TALE proteins, and the homology to TALE proteins of mosses, lycophytes, and seed plant species. The expression analyses demonstrate that these homeodomain proteins appear to have a key role in the establishment and development of the gametophyte and sporophyte phases of V. speciosa lifecycle, as well as in the control of the transition between both phases. Vandenboschia speciosa VsKNAT3 (a KNOX2 class protein) as well as VsBELL4 and VsBELL10 proteins have higher expression levels during the sporophyte program. On the contrary, one V. speciosa KNOX1 protein (VsKNAT6) and one KNOX2 protein (VsKNAT4) seem important during the development of the gametophyte phase. TALE homeobox genes might be among the key regulators in the gametophyte-to-sporophyte developmental transition in regular populations that show alternation of generations, since some of the genes analyzed here ( VsKNAT3 , VsKNAT6 , VsBELL4 , and VsBELL6 ) are upregulated in a non-alternating population in which only independent gametophytes are found (they grow by vegetative reproduction outside of the range of sporophyte distribution). Thus, these four genes might trigger the vegetative propagation of the gametophyte and the repression of the sexual development in populations composed of independent gametophytes. This study represents a comprehensive

  2. Phyto-toxicity and Phyto-remediation Potential of Mercury in Indian Mustard and Two Ferns with Mercury Contaminated Water and Oak Ridge Soil

    International Nuclear Information System (INIS)

    Su, Y.; Han, F.X.; Chen, J.; Shiyab, S.; Monts, D.L.; Monts, D.L.

    2009-01-01

    Phyto-remediation is an emerging technology that uses various plants to degrade, extract, contain, or immobilize contaminants from soil and water. Certain fern and Indian mustard species have been suggested as candidates for phyto-remediation of heavy metal-contaminated soil and water because of their high efficiency of accumulating metals in shoots and their high biomass production. Currently, no known hyper-accumulator plants for mercury have been found. Here we report the Hg uptake and phyto-toxicity by two varieties of fern and Indian mustard. Their potential for Hg phyto-remediation application was also investigated. Anatomical, histochemical and biochemical approaches were used to study mercury phyto-toxicity as well as anti-oxidative responses in ferns [Chinese brake fern (P. vittata) and Boston fern (N. exaltata)] and Indian mustard (Florida broadleaf and longstanding) (Brassica juncea L.) grown in a hydroponic system. Phyto-remediation potentials of these plant species were estimated based on their Hg uptake performance with contaminated soils from Oak Ridge (TN, USA). Our results show that mercury exposure led to severe phyto-toxicity accompanied by lipid peroxidation and rapid accumulation of hydrogen peroxide (H 2 O 2 ) in P. vittata, but not in N. exaltata. The two cultivars of fern responded differently to mercury exposure in terms of anti-oxidative enzymes (superoxide dismutase, SOD; catalase, CAT; peroxidase, POD; glutathione reductase, GR). Mercury exposure resulted in the accumulation of ascorbic acid (ASA) and glutathione (GSH) in the shoots of both cultivars of fern. On the other hand, Indian mustard effectively generated an enzymatic antioxidant defense system (especially CAT) to scavenge H 2 O 2 , resulting in lower H 2 O 2 in shoots with higher mercury concentrations. These two cultivars of Indian mustard demonstrated an efficient metabolic defense and adaptation system to mercury-induced oxidative stress. In both varieties of fern and Indian

  3. Synthesizing research and education: Ecology and genetics of independent fern gametophytes and teaching science inquiry and content through simulations

    Science.gov (United States)

    Duffy, Aaron M.

    Two of the main areas of focus in university academics are research and education. The mission statements of Utah State University and the Department of Biology emphasize both areas, as do the requirements of funding agencies. I attempted to integrate research and education by using tools that I developed to support and inform my biological research projects to teach science. Ferns have a life cycle with alternating haploid and diploid life stages, both of which are free-living and potentially long-lived. The haploid gametophytes of some ferns reproduce asexually and may have different environmental requirements than the diploid sporophytes, so it is possible for populations of gametophytes to exist without sporophytes. This dissertation includes a description of surveys for Hymenophyllum wrightii, a fern with independent gametophytes in the Pacific Northwest, and improves our understanding of the range, distribution, and habitat requirements of these plants which were previously assumed to be rare. It also describes an attempt to explore the population genetics of gametophytes of Crepidomanes intricatum, a widespread fern in the Appalachian Mountains for which no sporophytes have ever been found. To help visualize evolutionary processes in independent gametophyte populations I developed the Virtual Population Genetics Simulator (VPGsim) to simulate populations of ferns in a 3-dimensional environment. This dissertation includes a description of VPGsim, a learning module using it to teach undergraduate genetics, and a study demonstrating its effectiveness at improving students' understanding of science content and confidence in their ability to perform science inquiry. That simulation tool led to a collaboration to find other ways to teach science with simulations, and to the development of a Virtual Plant Community simulator (VPCsim) for teaching middle school students about the effects of the environment and human impacts on living organisms. This dissertation

  4. Functional groups of fossil marattialeans: Chemotaxonomic implications for Pennsylvanian tree ferns and pteridophylls

    Science.gov (United States)

    Psenicka, J.; Zodrow, E.L.; Mastalerz, Maria; Bek, J.

    2005-01-01

    Marattialean-fossil foliage, assigned to Pecopteris Brongniart, was an important and widespread floral component in Late Pennsylvanian mires, with phylogenetic affinity to extant marattialean taxa in tropical regions. Marattialean fossil taxonomy is, however, still uncertain. Specimens from the Pilsen limnic Basin, Westphalian D, Czech Republic, represent fertile marattialean foliage of Pecopteris (Asterotheca) nyranensis and Pecopteris (Asterotheca) miltonii, and sterile foliage of Pecopteris aspidioides and Pecopteris polypodioides. Taxonomic parameters for their assignments included cuticle, stomatal morphologies (studied for the first time), and in situ reproductive organs and spores. Chemotaxonomic interpretations hinge on fidelity of preservation of compounds, or molecular fragments thereof, that were synthesized by the once-living plants. This preservation state was possibly due to the thermal history (maximum temperature of 130 ??C) in the Pilsen Basin, acidic preservation conditions, lithology and facies stability. Although subtle, the four pecopterid species are differentiable from one another by combined FTIR characteristics, supporting taxonomy. The ratio of CH2/CH3 is hypothesized to be a chemotaxonomic parameter for Pennsylvanian pteridophylls, both in seed and true ferns that have previously been studied. It will, however, be supplemented by additional biochemical markers. ?? 2004 Elsevier B.V. All rights reserved.

  5. Conflict amongst chloroplast DNA sequences obscures the phylogeny of a group of Asplenium ferns.

    Science.gov (United States)

    Shepherd, Lara D; Holland, Barbara R; Perrie, Leon R

    2008-07-01

    A previous study of the relationships amongst three subgroups of the Austral Asplenium ferns found conflicting signal between the two chloroplast loci investigated. Because organelle genomes like those of chloroplasts and mitochondria are thought to be non-recombining, with a single evolutionary history, we sequenced four additional chloroplast loci with the expectation that this would resolve these relationships. Instead, the conflict was only magnified. Although tree-building analyses favoured one of the three possible trees, one of the alternative trees actually had one more supporting site (six versus five) and received greater support in spectral and neighbor-net analyses. Simulations suggested that chance alone was unlikely to produce strong support for two of the possible trees and none for the third. Likelihood permutation tests indicated that the concatenated chloroplast sequence data appeared to have experienced recombination. However, recombination between the chloroplast genomes of different species would be highly atypical, and corollary supporting observations, like chloroplast heteroplasmy, are lacking. Wider taxon sampling clarified the composition of the Austral group, but the conflicting signal meant analyses (e.g., morphological evolution, biogeographic) conditional on a well-supported phylogeny could not be performed.

  6. High gene flow in epiphytic ferns despite habitat loss and fragmentation.

    Science.gov (United States)

    Winkler, Manuela; Koch, Marcus; Hietz, Peter

    2011-01-01

    Tropical montane forests suffer from increasing fragmentation and replacement by other types of land-use such as coffee plantations. These processes are known to affect gene flow and genetic structure of plant populations. Epiphytes are particularly vulnerable because they depend on their supporting trees for their entire life-cycle. We compared population genetic structure and genetic diversity derived from AFLP markers of two epiphytic fern species differing in their ability to colonize secondary habitats. One species, Pleopeltis crassinervata , is a successful colonizer of shade trees and isolated trees whereas the other species, Polypodium rhodopleuron , is restricted to forests with anthropogenic separation leading to significant isolation between populations. By far most genetic variation was distributed within rather than among populations in both species, and a genetic admixture analysis did not reveal any clustering. Gene flow exceeded by far the benchmark of one migrant per generation to prevent genetic divergence between populations in both species. Though populations are threatened by habitat loss, long-distance dispersal is likely to support gene flow even between distant populations, which efficiently delays genetic isolation. Consequently, populations may rather be threatened by ecological consequences of habitat loss and fragmentation.

  7. Fernández Álvarez: compromiso y rigor de un modernista

    Directory of Open Access Journals (Sweden)

    Francisco CHACÓN JIMÉNEZ

    2011-07-01

    Full Text Available Es difícil sintetizar toda una trayectoria vital de setenta años de dedicación completa a la Historia. Los titulares de prensa en el día de su fallecimiento le calificaban de: «César y Hombre de la Historia de España»; «el historiador con lírica»; «el iluminador de la Historia de España»; «el historiador por excelencia de la España del Siglo de Oro»; «gran investigador y catedrático ejemplar»; «el biógrafo de España»; «el gran divulgador de nuestro pasado». Son algunos de los titulares de prensa que el pasado 20 de abril de 2010 anunciaban el fallecimiento del insigne historiador. En realidad la síntesis de todas ellas anuncia el significado, la personalidad y el ejemplo de lo que fue y quiso ser Manuel Fernández Álvarez.

  8. Interdisciplinary study of the panel painting depicting the "Pentecostes", attributed to Fernão Gomes

    Directory of Open Access Journals (Sweden)

    Diana Conde

    2010-01-01

    Full Text Available This paper presents a study on the technique and materials used in the panel painting entitled Pentecostes, attributed to the artist Fernão Gomes (XVIIth century, housed in the Museu Nacional de Arte Antiga, in Lisbon. The study also includes the diagnosis of the conservation state of the painting and the description of the cleaning intervention. For identification of the materials and determination of the conservation state, several analytical techniques were used: micro-FTIR and GC-MS, for identification of the binder and varnish; micro-Raman and micro-FTIR, for identification of fillers and pigments; micro-XRF and SEM-EDX, for elemental analysis; optical microscopy, with visible and fluorescent radiation, and infrared photography, for morphological observation and study of pictorial technique. The analytical approach led to the identification of materials common at the time: gypsum with animal glue, lead white, yellow and red ochres, black earths (based on Mn, Bi, Fe, azurite, possible green earth, lead red, oil and oily varnish with residues of cholesterol. After various cleaning tests, a gel suggested by the literature was chosen (recipe no. 105.4 developed by R. Wolbers and proved to be effective in the removal of the aged and polymerized varnish.

  9. The potential of the fresh-water fern Azolla in aquatic farming systems

    Science.gov (United States)

    Bijl, Peter K.; Werf, vd, Adrie; Schluepmann, Henriette; Reichart, Gert-Jan; Brouwer, Paul; Nierop, Klaas G. J.; Hellgardt, Klaus; Brinkhuis, Henk

    2014-05-01

    With aquatic farming systems a new avenue in agriculture is explored, in which the competition with conventional arable land is avoided. The aquatic, ubiquitous, floating fern Azolla is not yet widely explored as potential crop in such farming systems, despite its high potential because it grows in many natural systems under low-light intensities, has an enormous annual yield, and has special biomass qualities for applications in food, feed and specialty chemical industries. But, what makes Azolla particularly interesting as cost-effective crop is its capability to take up atmospheric nitrogen through symbiosis with nitrogen-fixing bacteria Anabaena azollae. This makes Azolla independent of nitrogen fertilization. In order to explore the potential of Azolla as a crop for a suite of applications, we have assembled a team of expertise: AZOFAST, consisting of agricultural engineers, plant physiologists, chemical engineers and organic chemists. Our growth experiments reveal high annual production yields with constant harvest. We are developing a germination and spore collecting/preservation protocol as a first step to domestication. Finally we have explored the biomass quality of different species of extant Azolla. We performed organic chemical analyses on lipid and tannin extracts, and quantified yields of specific compounds within these fractions. In our presentation we will present some of our results to show the potential of Azolla as a new, sustainable aquatic crop serving all kinds of industrial streams from protein feed to platform chemicals.

  10. Thiol synthesis and arsenic hyperaccumulation in Pteris vittata (Chinese brake fern)

    International Nuclear Information System (INIS)

    Zhang Weihua; Cai Yong; Downum, Kelsey R.; Ma, Lena Q.

    2004-01-01

    Pteris vittata (Chinese brake fern) has potential for phytoremediation of As-contaminated sites. In this study, the synthesis of total thiols and acid-soluble thiols in P. vittata was investigated under arsenic exposure. The strong and positive correlation between As concentration and acid-soluble thiols in plant leaflets suggests that acid-soluble thiols may play a role in As detoxification. A major As-induced thiol was purified and characterized. A molecular ion (M+1) of 540 m/z suggests that the thiol was a phytochelatin (PC) with two base units (PC 2 ). However, the ratios of acid-soluble thiols to As in leaflets exposed to As ranged from 0.012 to 0.026, suggesting that only a very small part of As is complexed by PC 2 . PCs could play a minor detoxification role in this hyperaccumulator. A PC-independent mechanism appears to be mainly involved in As tolerance, while PC-dependent detoxification seems to be a supplement

  11. Thiol synthesis and arsenic hyperaccumulation in Pteris vittata (Chinese brake fern)

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Weihua; Cai Yong; Downum, Kelsey R.; Ma, Lena Q

    2004-10-01

    Pteris vittata (Chinese brake fern) has potential for phytoremediation of As-contaminated sites. In this study, the synthesis of total thiols and acid-soluble thiols in P. vittata was investigated under arsenic exposure. The strong and positive correlation between As concentration and acid-soluble thiols in plant leaflets suggests that acid-soluble thiols may play a role in As detoxification. A major As-induced thiol was purified and characterized. A molecular ion (M+1) of 540 m/z suggests that the thiol was a phytochelatin (PC) with two base units (PC{sub 2}). However, the ratios of acid-soluble thiols to As in leaflets exposed to As ranged from 0.012 to 0.026, suggesting that only a very small part of As is complexed by PC{sub 2}. PCs could play a minor detoxification role in this hyperaccumulator. A PC-independent mechanism appears to be mainly involved in As tolerance, while PC-dependent detoxification seems to be a supplement.

  12. Arundina graminifolia var. revoluta (Arethuseae, Orchidaceae) has fern-type rheophyte characteristics in the leaves.

    Science.gov (United States)

    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.

  13. Sporangium Exposure and Spore Release in the Peruvian Maidenhair Fern (Adiantum peruvianum, Pteridaceae.

    Directory of Open Access Journals (Sweden)

    Simon Poppinga

    Full Text Available We investigated the different processes involved in spore liberation in the polypod fern Adiantum peruvianum (Pteridaceae. Sporangia are being produced on the undersides of so-called false indusia, which are situated at the abaxial surface of the pinnule margins, and become exposed by a desiccation-induced movement of these pinnule flaps. The complex folding kinematics and functional morphology of false indusia are being described, and we discuss scenarios of movement initiation and passive hydraulic actuation of these structures. High-speed cinematography allowed for analyses of fast sporangium motion and for tracking ejected spores. Separation and liberation of spores from the sporangia are induced by relaxation of the annulus (the 'throwing arm' of the sporangium catapult and conservation of momentum generated during this process, which leads to sporangium bouncing. The ultra-lightweight spores travel through air with a maximum velocity of ~5 m s(-1, and a launch acceleration of ~6300 g is measured. In some cases, the whole sporangium, or parts of it, together with contained spores break away from the false indusium and are shed as a whole. Also, spores can stick together and form spore clumps. Both findings are discussed in the context of wind dispersal.

  14. Geometry, Allometry and Biomechanics of Fern Leaf Petioles: Their Significance for the Evolution of Functional and Ecological Diversity Within the Pteridaceae

    Directory of Open Access Journals (Sweden)

    Jennifer N. Mahley

    2018-03-01

    Full Text Available Herbaceous plants rely on a combination of turgor, ground tissues and geometry for mechanical support of leaves and stems. Unlike most angiosperms however, ferns employ a sub-dermal layer of fibers, known as a hypodermal sterome, for support of their leaves. The sterome is nearly ubiquitous in ferns, but nothing is known about its role in leaf biomechanics. The goal of this research was to characterize sterome attributes in ferns that experience a broad range of mechanical stresses, as imposed by their aquatic, xeric, epiphytic, and terrestrial niches. Members of the Pteridaceae meet this criteria well. The anatomical and functional morphometrics along with published values of tissue moduli were used to model petiole flexural rigidity and susceptibility to buckling in 20 species of the Pteridaceae. Strong allometric relationships were observed between sterome thickness and leaf size, with the sterome contributing over 97% to petiole flexural rigidity. Surprisingly, the small-statured cheilanthoid ferns allocated the highest fraction of their petiole to the sterome, while large leaves exploited aspects of geometry (second moment of area to achieve bending resistance. This pattern also revealed an economy of function in which increasing sterome thickness was associated with decreasing fiber cell reinforcement, and fiber wall fraction. Lastly, strong petioles were associated with durable leaves, as approximated by specific leaf area. This study reveals meaningful patterns in fern leaf biomechanics that align with species leaf size, sterome attributes and life-history strategy.

  15. Determination of thermal stability of specific biomarker lipids of the freshwater fern Azolla through hydrous pyrolysis

    Science.gov (United States)

    Sap, Merel; Speelman, Eveline N.; Lewan, Michael D.; Sinninghe Damsté, Jaap S.; Reichart, Gert-Jan

    2010-05-01

    Enormous blooms of the free-floating freshwater fern Azolla occurred within the Arctic Basin during an extended period of ~1.2 Ma during the middle Eocene (Brinkhuis et al. 2006; Speelman et al., GB, 2009). The sustained growth of Azolla, currently ranking among the fastest growing plants on Earth, in a major anoxic basin may have substantially contributed to decreasing atmospheric CO2 levels by burial of Azolla-derived organic matter. Speelman et al. (OG, 2009) reported biomarkers for Azolla (1,w20 C32 - C36 diols, structurally related C29 ω20,ω21 diols, C29 1,20,21 triols, C29 dihydroxy fatty acids as well as a series of wax esters containing these mono- and dihydroxy lipids), which can be used to reconstruct palaeo-environmental conditions. Here we assess the thermal stability of these compounds, to extend their biomarker potential. We specifically focused on the thermal stability of the Azolla biomarkers using hydrous pyrolysis in order to determine which burial conditions allow reconstruction of past occurrences of Azolla. In addition, hydrous pyrolysis was also performed on samples from the Eocene Arctic Ocean (ACEX core), to test if and how the biomarkers change under higher temperatures and pressures in situ. During hydrous pyrolysis, the biomass was heated under high pressure at temperatures ranging between 220 and 365°C for 72 hours. Four experiments were also run using different durations to explore the kinetics of biomarker degradation at specific temperatures. First results indicate that the Azolla specific diols are still present at 220°C, while the corresponding wax esters are already absent. At 300°C all Azolla specific biomarkers are destroyed. More specific determination of the different biomarkers' stability and kinetics would potentially allow the reconstruction of the temperature and pressure history of Azolla deposits. Literature: • Brinkhuis, H., Schouten, S., Collinson, M. E., Sluijs, A., Sinninghe Damste, J. S., Dickens, G. R., Huber

  16. La colección Fernández Rivero de fotografía antigua

    Directory of Open Access Journals (Sweden)

    García Ballesteros, María Teresa

    2015-02-01

    Full Text Available La Colección Fernández Rivero de fotografía antigua es una colección de objetos fotográficos originales de más de 45000 piezas de diversa tipología. La CFRivero ha seguido para su formación un criterio historicista de manera que pudiese cubrir fines museísticos y didácticos. Alrededor de dos tercios de sus piezas son del siglo XIX, de las cuales la mayor parte podrían describirse como parte fundamental del patrimonio fotográfico español de este periodo. Es por tanto una colección fundamentalmente de fotografía histórica española, aunque contiene también notables ejemplos representativos de fotografía de Francia, Reino Unido y otros países, además de dos secciones especiales: fotografía estereoscópica y fotografía relacionada con Málaga y su provincia. Se complementa con máquinas y otros objetos fotográficos así como con una nutrida biblioteca antigua y contemporánea. Los propietarios vienen desarrollando una amplia labor de difusión e investigación del fenómeno fotográfico, centrado especialmente en el siglo XIX. Para ello se han publicado libros y artículos, celebrado exposiciones, conferencias y talleres, así como una amplia y activa difusión a través de Internet.

  17. Phytochemistry of the fossilized-cuticle frond Macroneuropteris macrophylla (Pennsylvanian seed fern, Canada)

    Energy Technology Data Exchange (ETDEWEB)

    Zodrow, Erwin L. [Palaeobotanical Laboratory, Cape Breton University, Sydney, Nova Scotia, B1P 6L2 (Canada); D' Angelo, Jose A. [IANIGLA, CCT-CONICET-Mendoza, Avda. Ruiz Leal s/n Parque Gral. San Martin (5500) Mendoza (Argentina); Mastalerz, Maria [Indiana Geological Survey, Indiana University, Bloomington, IN, 47405-2208 (United States); Cleal, Christopher J. [Department of Biodiversity and Systematic Biology, National Museum of Wales, Cathays Park, Cardiff, CF10 3NP (United Kingdom); Keefe, Dale [Molecular Spectroscopy Research Laboratory, Department of Chemistry, Cape Breton University, Sydney, Nova Scotia (Canada)

    2010-11-01

    In Canada's Sydney Coalfield, specimens of the extinct Carboniferous seed fern Macroneuropteris macrophylla (Brongniart) invariably show preservation stages intermediate between compression and fossilized-cuticle, even concerning a single pinnule. In this interdisciplinary approach, we study a ca. 300 to 350 mm long fossilized-cuticle-preserved frond section of M. macrophylla (Brongniart) that represents about one third of the length of a frond that was originally 1 m long. Size and preservation allow us to study the phytochemistry of the cuticle biomacropolymers over the length of the frond to assess what impact, if any, results would have on Carboniferous palaeophytochemotaxonomy. For comparison, the phytochemistry of compressions with their extracted cuticles from the same species and the same sample locality is also investigated. We use solid- and liquid-state, semi-quantitative Fourier transform infrared spectroscopy (FTIR) for the chemical characterization of the frond. Based on our results, we infer an essentially uniform phytochemistry over the fossilized-cuticle frond, suggesting that only a single pinnule needs to be analyzed to get an overall phytochemical picture of the frond, which has been our long-time working hypothesis. We distinguish between phytochemistry and cutinization. The latter is much less pronounced above than below the frond dichotomy, and we suggest a palaeoecological cause, rather than differing pathways of organic matter transformation. Moreover, cuticles below and above the frond dichotomy have essentially the same epidermal pattern, but those from below have features that may have been an adaptation to prevent stomatal flooding during the tropical, rainy season. This study suggests that chemically the fossilized-cuticle is more similar to the compression than to the cuticle obtained from that compression of the same species which invites reevaluation of the classical compression concept. (author)

  18. Phytochemistry of the fossilized-cuticle frond Macroneuropteris macrophylla (Pennsylvanian seed fern, Canada)

    Science.gov (United States)

    Zodrow, E.L.; D'Angelo, J. A.; Mastalerz, Maria; Cleal, C.J.; Keefe, D.

    2010-01-01

    In Canada's Sydney Coalfield, specimens of the extinct Carboniferous seed fern Macroneuropteris macrophylla (Brongniart) invariably show preservation stages intermediate between compression and fossilized-cuticle, even concerning a single pinnule. In this interdisciplinary approach, we study a ca. 300 to 350 mm long fossilized-cuticle-preserved frond section of M. macrophylla (Brongniart) that represents about one third of the length of a frond that was originally 1 m long. Size and preservation allow us to study the phytochemistry of the cuticle biomacropolymers over the length of the frond to assess what impact, if any, results would have on Carboniferous palaeophytochemotaxonomy. For comparison, the phytochemistry of compressions with their extracted cuticles from the same species and the same sample locality is also investigated. We use solid- and liquid-state, semi-quantitative Fourier transform infrared spectroscopy (FTIR) for the chemical characterization of the frond.Based on our results, we infer an essentially uniform phytochemistry over the fossilized-cuticle frond, suggesting that only a single pinnule needs to be analyzed to get an overall phytochemical picture of the frond, which has been our long-time working hypothesis. We distinguish between phytochemistry and cutinization. The latter is much less pronounced above than below the frond dichotomy, and we suggest a palaeoecological cause, rather than differing pathways of organic matter transformation. Moreover, cuticles below and above the frond dichotomy have essentially the same epidermal pattern, but those from below have features that may have been an adaptation to prevent stomatal flooding during the tropical, rainy season.This study suggests that chemically the fossilized-cuticle is more similar to the compression than to the cuticle obtained from that compression of the same species which invites reevaluation of the classical compression concept. ?? 2010 Elsevier B.V.

  19. The potential of the aquatic water fern Azolla within a biobased economy

    Science.gov (United States)

    Nierop, Klaas G. J.; Jongerius, Anna L.; Bijl, Peter K.; Bruijnincx, Pieter C. A.; Klein Gebbink, Robertus J. M.; Reichart, Gert-Jan

    2014-05-01

    Azolla is a free-floating freshwater fern capable of fixing atmospheric carbon dioxide and nitrogen, the latter of which through its symbiosis with the cyanobacteria Anabaena azollae. It is currently ranked among the fastest growing plants on Earth and occurs in both tropical and temperate freshwater ecosystems. Therefore, it is non-directly competitive with food crops. In addition, Azolla does not require inorganic fertilizers, which makes it a potential and unique source of biomass for the sustainable production of fuels and chemicals that are currently derived from fossil (fuel) sources. The biochemical composition of Azolla allows the production of biofuel or biobased chemicals that are of interest to the chemical industry. Of Azolla, two extractable groups of compounds are of particular interest, i.e. the polyphenols (condensed tannins and ester-bound caffeic acid) and the lipids. The antioxidant property of polyphenols and their application to the treatment of cancer, diabetes and cardiovascular diseases has further contributed to the growth of the polyphenol market. In addition, they can be chemically transformed into aromatic platform and specialty chemicals. The composition of the lipid fraction of Azolla is characterized by highly specific compounds consisting of C26-C36 carbon chains all bearing a ω20-hydroxy group. Such compounds produce an oil fraction upon hydrous pyrolysis, or, alternatively, are well suited to be converted to e.g. various specialty chemicals that are hardly available from both natural sources. Indeed, upon chemical conversion these lipids may yield components for fuels, plastics, cosmetics, and lubricants. Another group of interesting compounds within the lipid group are the polyunsaturated fatty acids (PUFAs). The demand for PUFAs has witnessed a significant increase over the last three years, particularly due to their benefits as cholesterol lowering agents. Here we will present some of the thermal and chemical conversions of the

  20. On climate adaptability of nine species of Adiantum ornamental ferns in 34 provincial capital cities,China

    Directory of Open Access Journals (Sweden)

    CHEN Yunhui

    2015-10-01

    Full Text Available Adiantum malesianum,A. myriosorum,A. capillus-junonis,A. capillus-veneris,A. caudatum,A. davadii,A. deentulum,A. edgeworthii and A. erythrochlamys are nine ornamental ferns of the family Adinataceae,with potential application prospect in the aspect of urban landscape and greening construction.To understand their climatic adaptation characteristics in 34 provincial capital cities in China,so as to provide the guidance for their cultivation.Based on 11 current biological climate data in RCP45CO2 emissions scenario,and 694 occurrence records in China,records,MaxEnt model and Arc Gis9.3 software were applied to quantitatively predict the potential distribution ranges of these nine fern species in China.The results show a quietly differences among the nine fern species in their climatic adaptation in 34 provincial capital cities.A. malesianum,A. myriosorum,A. capillus-junonis,A. capillus-veneris,A. deentulum and A. edgeworthii are more suitable grow in southwest China including Southeastern Sichuan,Chongqing,Yunnan,Guizhou,with wider potential distribution ranges;A. malesianum,A. capillus-junonis,A. capillus-veneris and A. caudatum have higher climatic adaptability in Southern China;Adiantum myriosorum,A. capillus-junonis,A. capillus-veneris,A. davadii and A. edgeworthii have higher climate adaptability in Central China;The potential distribution ranges of A. capillus-junonis and A. edgeworthii cover the north area of Beijing,Tianjin and Shijiazhuang,with their combined climate suitability index reaching as high as 0.60.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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).

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

    Science.gov (United States)

    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.

  4. Explotación de peces asociada a la pesquería artesanal de langosta de Juan Fernández (Jasus frontalis

    Directory of Open Access Journals (Sweden)

    Mauricio Ahumada

    2014-03-01

    Full Text Available Para contribuir al conocimiento de la explotación de peces asociada a la pesquería de langosta de Juan Fernández, se monitorearon 157 salidas de pesca durante la temporada 2010-2011. Se capturaron 10.462 ejemplares correspondientes a 19 especies de peces, tres de las cuales concentraron el 94% de la captura en número: jurel de Juan Fernández (Pseudocaranx chilensis (45%, breca (Nemadactylus gayi (41% y anguila morena (Gymnothoraxporphyreus (8%. Las capturas totales estimadas fueron 40, 24 y 13 ton de breca, jurel de Juan Fernández y anguila morena, respectivamente. El 97% de los ejemplares de peces capturados fueron utilizados como carnada de peces o langosta.

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

    Energy Technology Data Exchange (ETDEWEB)

    Zodrow, Erwin L. [Department of Earth Sciences, University College of Cape Breton, PO Box 5300, Nova Scotia, B1P 6L2 Sydney (Canada); Mastalerz, Maria [Indiana Geological Survey, Indiana University, 611 North Walnut Grove, 47405-2208 Bloomington, IN (United States)

    2001-07-01

    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 CH{sub 2}/CH{sub 3} 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.

  6. 15 June 2009 - President of the Argentine Nation C. Fernández visiting ATLAS experimental area.

    CERN Document Server

    Maximilien Brice

    2009-01-01

    Tirage 1:President of the Argentine Nation, C. Fernández and Minister of Science, Technology and Innovative Production,L. Barañao Tirage 2-8:Arrival greetings Tirage 9-12:Introduction to CERN's activities by Director-General, R. Heuer Tirage 13-15:Signature of the guest book Tirage 16-25:M. Benedetti,R. Heuer and L.Barañao sit for the signature of the Agreement Tirage 26-33: Meeting with Argentinian scientists at CERN

  7. Developing and Deploying an XML-based Learning Content Management System at the FernUniversität Hagen

    Directory of Open Access Journals (Sweden)

    Gerd Steinkamp

    2005-02-01

    Full Text Available This paper is a report about the FuXML project carried out at the FernUniversität Hagen. FuXML is a Learning Content Management System (LCMS aimed at providing a practical and efficient solution for the issues attributed to authoring, maintenance, production and distribution of online and offline distance learning material. The paper presents the environment for which the system was conceived and describes the technical realisation. We discuss the reasons for specific implementation decisions and also address the integration of the system within the organisational and technical infrastructure of the university.

  8. La escritora Ana de Zayas y el obispo poblano Manuel Fernández de Santa Cruz

    Directory of Open Access Journals (Sweden)

    Zayas, Concepción

    2001-06-01

    Full Text Available Estudio de caso sobre la relación entre el obispo de la diócesis angelopolitana, don Manuel Fernández de Santa Cruz, y doña Ana de Zayas, escritora que la Inquisición novohispana procesó por alumbrada de 1694 a 1700. Este trabajo analiza principalmente la intervención del prelado a favor de esta mujer, lo cual impidió que ella fuera condenada por el Santo Oficio de México. El artículo se basa en fuentes mexicanas y españolas.

  9. Proyecto conservación, restauración y desarrollo de las islas Juan Fernández, Chile

    OpenAIRE

    CUEVAS, JAIME G.; VAN LEERSUM, GART

    2001-01-01

    From a scientific point of view, the Juan Fernández islands contain one of the most interesting floras of the planet. Although protected as a National Park and a World Biosphere Reserve, 400 years of human interference have left deep traces in the native plant communities. Repeated burning, overexploitation of species, and the introduction of animal and plant plagues have taken 75 % of the endemic vascular flora to the verge of extinction. In 1997, Chile's national forest service (Corporación...

  10. Hasta siempre Profesor Manuel Fernández: Palabras en homenaje al ex Decano de la Facultad de Arquitectura y Urbanismo Dr. Arqto. Manuel Fernández Hechenleitner (1946- 2003. / Farewell, Professor Manuel Fernandez: Words in tribute to the former - Dean of the Faculty of Architecture and Planning Dr. Arqto. Manuel Fernández Hechenleitner (1946 - 2003.

    Directory of Open Access Journals (Sweden)

    Javier de Cárdenas

    2003-06-01

    Full Text Available Académicos, ex alumnos y amigos de la Facultad de Arquitectura y Urbanismo de la Universidad de Chile, recuerdan la personalidad del Dr. Arquitecto Manuel Fernández Hechenleitner (1946-2003, ex Decano de la F.A.U., con motivo de su fallecimiento./Academics, ex - students and friends of the School of Architecture and Urbanism of the University of Chile, remember the personality of Dr. Manuel Fernandez Hechenleitner Architect (1946-2003, ex - Dean of the FAU, on the occasion of his death.

  11. Phylogeny and character evolution of the fern genus Tectaria (Tectariaceae) in the Old World inferred from chloroplast DNA sequences.

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  14. Raíces medievales del nacional catolicismo: el Poema de Fernán González

    Directory of Open Access Journals (Sweden)

    Moreno Hernández, Carlos

    2000-06-01

    Full Text Available The Poema de Fernán González, a clerical poem written in the second half of the XIIIth century, includes already the national catholic ideology governing Spain up to the present, a religious fundamentalism that christians in the castilian kingdom did oppose to the one by their muslim enemies, always permeating the stories about this half legendary nobleman and exemplifying the blurring borders between history and literature before the XlXth century.[fr] Le Poema de Fernán González, poème de clérecie redige pendant la seconde moitié du XIIème siècle, resume déjà l'idéologie du national catolicisme qui va s'imposer en Espagne jusqu'à nos jours. Il s'agit d'un fondamentalisme religieux que les chrétiens du royaume castillan finirent par opposser à celui de ses énemis musulmans et qu'on peut trouver aussi dans tous les récits ultérieurs sur le comte, exemples des frontières peu claires entre les domaines historique et littéraire jusqu'au XIXème siècle.

  15. The aquatic fern Azolla as a natural plant-factory for ammonia removal from fish-breeding fresh wastewater.

    Science.gov (United States)

    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.

  16. Distribution patterns of ferns and lycophytes in the Coastal Region of the state of Rio Grande do Sul, Brazil

    Directory of Open Access Journals (Sweden)

    Felipe Gonzatti

    2016-01-01

    Full Text Available ABSTRACT A survey of ferns and lycophytes of the Coastal Region of the state of Rio Grande do Sul (CRRS was performed based on field work and collections of the main regional herbaria. The following were evaluated for each species: preferential habits (terrestrial, epiphytic or aquatic, geographic distribution patterns and habitats (forest, grassland, and wetland. The occurrence of a latitudinal gradient in diversity was tested over five latitudinal ranges using the Sørensen Similarity Index. A total of 17 lycophyte and 206 fern species representing 28 families was found between the latitudes of 29° and 34°S. Exclusively terrestrial species were predominant (162, with the majority (113 exhibiting wide Neotropical distributions, followed by species that also occurred in the state of Paraná (44. The forest habitat harbored the greatest number of species (159, while grasslands had the fewest (26. Cluster analysis showed pronounced floristic differentiation among latitudinal Ranges III (31°01' to 32°S and IV (32°01' to 31°S, with a similarity index of only 0.41. Our results demonstrate a strong north-to-south reduction in species richness in the study area, which is related to environmental conditions along the latitudinal gradient and, especially, microclimatic differences in the transition zone between the Atlantic Forest and Pampa biomes.

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

    Science.gov (United States)

    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.

  18. Dylan Thomas’s “Fern Hill”: The Poets’s Passion for Auden’s Greatness

    Directory of Open Access Journals (Sweden)

    S. Bharadwaj

    2017-09-01

    Full Text Available The poem “Fern Hill” is interpreted as autobiographical and reminiscent of Dylan Thomas’s boyhood holidays. A reading of the figurative language of the poem, the process of playing with its tropes can be the basis of right interpretation independent of the poet’s life or an historical context. As the poem seeks to be persuasive and objective, it relies more on rhetorics suggesting the sufferings of the fallen poets of the thirties and the war poet of the forties owing to their wild love of the transcendental art of W.H.Auden’s Poems (1930 considered as touchstone of great poetry and a hope for self-advancement in life. However, it is the paradoxical poems of Thomas and his vicarious poetical character that have rehabilitated and revamped the depressed poets. “Fern Hill” reaffirms and reassures the continuation of the same sceptic poetic tradition and culture which Thomas has cherished in all the preceeding and the succeeding poems. What this paper, keeping the contemporary poets’s passion for Auden’s greatness and glory, their dreams and destinations as focal point, strives to convey is the liberating power of Thomas’s moral disinterestedness, his vicarious comic vision and his poetic process of life-in-death contrasted with  the amoral aesthetic disinterestedness of Auden, his historic tradition and his poetic process of death-in-life.

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

    Directory of Open Access Journals (Sweden)

    A. C. D. Castello

    Full Text Available Abstract 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.

  20. Acrostichum, a Pioneering Fern of Floodplain Areas from the Late Oligocene Sariñena Formation of the Iberian Peninsula.

    Directory of Open Access Journals (Sweden)

    Rafael Moreno-Domínguez

    Full Text Available Acrostichum is considered today an opportunistic fern in disturbed areas, which indicates the first stages of colonisation of such zones. However, in the fossil record, Acrostichum appears related to fluvio-lacustrine environments, freshwater marshes and mangrove deposits. We report here for first time fossil evidence of Acrostichum that reveals a pioneering behaviour of this fern in the colonisation of perturbed communities in Europe, which corroborates previous assumptions about the paleobiology of Acrostichum. Plant remains were collected from the Chattian (late Oligocene La Val fossil site (Estadilla, Huesca, northeastern Spain belonging to the Sariñena Formation, which mainly embraces crevasse splays, levees and floodplain deposits. Evidence shows that Acrostichum grew within the levee's vegetal community or close to/on the river banks as well as on floodplain areas and closer to/on the shores of ephemeral ponds. But most importantly, the observed co-existence of Equisetum and Acrostichum remains in the same beds indicates that such strata represent short-lived inundated terrains, e.g., floodplains where the water table was temporarily stagnant. Evidence shows wetland environments dominated by pioneering taxa, implying a pioneering role for Acrostichum during the late Oligocene in the Iberian Peninsula.

  1. Fertile organs and in situ spores of a new dipteridaceous fern Hausmannia sinensis from the Jurassic of northern China.

    Science.gov (United States)

    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.

  2. Phylogeny and systematics of the brake fern genus Pteris (Pteridaceae) based on molecular (plastid and nuclear) and morphological evidence.

    Science.gov (United States)

    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.

  3. A new schizaeaceous fern, Schizaeopsis ekrtii sp nov., and its in situ spores from the Upper Cretaceous (Cenomanian) of the Czech Republic

    Czech Academy of Sciences Publication Activity Database

    Kvaček, J.; Dašková, Jiřina; Pátová, R.

    2006-01-01

    Roč. 140, 1-2 (2006), s. 51-60 ISSN 0034-6667 R&D Projects: GA ČR GA205/03/1267 Institutional research plan: CEZ:AV0Z30130516 Keywords : fern * palaeobotany * spores * Cenomanian Subject RIV: EF - Botanics Impact factor: 1.170, year: 2006

  4. Un texto inédito de Wenceslao Fernández Flórez. "¡S.O.S.! ¡Aquí Europa!"

    Directory of Open Access Journals (Sweden)

    María Teresa BARBADILLO

    2009-11-01

    Full Text Available Publicamos aquí un texto inédito de Wenceslao Fernández Flórez contenido en 23 cuartillas escritas de su puño y letra, que me fueron confiadas generosamente por sus sobrinos Wenceslao y Antonio Fernández Flórez. El manuscrito no lleva fecha alguna, y el sobre que lo contenía sólo reproduce el título, con la indicación «Charla radiofónica». Don Antonio Fernández Flórez tiene idea de que data de 1934 ó 35, posiblemente del mes de octubre. No obstante, ni en la prensa de esos años, ni en los archivos del Servicio de Documentación escrita de Radio Nacional de España —en donde nos atendieron con suma amabilidad— queda constancia de esta intervención de Fernández Flórez a través de las ondas.

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

    Science.gov (United States)

    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...

  6. 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

    NARCIS (Netherlands)

    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

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

    Science.gov (United States)

    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.

  8. Revision of the Pennsylvanian fern .i.Boweria./i. Kidston and the establishment of the new genus .i.Kidstoniopteris./i.

    Czech Academy of Sciences Publication Activity Database

    Frojdová, Jana; Pšenička, J.; Bek, Jiří; Cleal, Ch. J.

    2017-01-01

    Roč. 236, January (2017), s. 33-58 ISSN 0034-6667 R&D Projects: GA ČR(CZ) GAP210/12/2053 Institutional support: RVO:67985831 Keywords : Boweria * Kidstoniopteris * fern * Pennsylvanian * in situ spores * taxonomy * cuticles Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Paleontology Impact factor: 1.817, year: 2016

  9. Rapid allopolyploid radiation of moonwort ferns (Botrychium; Ophioglossaceae) revealed by PacBio sequencing of homologous and homeologous nuclear regions.

    Science.gov (United States)

    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

  10. Biometry of stomata in Blechnum species (Blechnaceae with some taxonomic and ecological implications for the ferns

    Directory of Open Access Journals (Sweden)

    José María Gabriel y Galán

    2011-03-01

    Full Text Available Morphological stomatal traits, such as size, form and frequency, have been subject of much literature, including their relationships with environmental factors. However, little effort have focused on ferns, and very few in the genus Blechnum. Stomatal length, width and frequency (as stomatal index of a number of specimens of fourteen Neotropical species of Blechnum were measured in adult pinnae. The aim of the work was to find biometrical relationships between stomatal traits and between stomatal traits and habit, habitat and ecosystem of the plants. Statistical analyses of data were conducted using Exploratory Data Analysis and Multivariate Statistical Methods. Stomatal length and width showed a very high correlation, suggesting an endogenous, genetic control, thus giving these traits a considerable diagnostic utility. With respect to the relationships between stomatal traits and environment, we found significant statistical relationships between altitude and stomatal index. We also addressed the interpretation of the ecological- selective significance of various assemblages of stomatal traits in a diverse conjunction of habits, habitats and ecosystems. Rev. Biol. Trop. 59 (1: 403-415. Epub 2011 March 01.Los caracteres morfológicos estomáticos, tales como tamaño, forma y frecuencia, han sido objeto de abundante investigación, incluyendo su relación con los factores ambientales. Sin embargo, poco esfuerzo se ha realizado en esta materia en helechos y menos todavía en el género Blechnum. En este trabajo se midieron la longitud, anchura y frecuencia (como índice estomático de estomas de pinnas adultas de un número de individuos en catorce especies de Blechnum neotropicales. El objetivo fue encontrar relaciones biométricas entre los caracteres estomáticos, y entre los caracteres estomáticos y el hábito, hábitat y ecosistema de las plantas. Se realizaron análisis estadísticos como Análisis Exploratorios de Datos y Métodos Estad

  11. El Cura Juan Fernández de Sotomayor y Picón y los catecismos de la Independencia

    OpenAIRE

    Ocampo López, Javier

    2010-01-01

    Este libro presenta el entorno revolucionario de finales del siglo XVIII y primera mitad del siglo XIX, a través del pensamiento y la acción del cura cartagenero Juan Fernández de Sotomayor y Picón, Cura de Mompós y rector del colegio Mayor de Nuestra Señora del Rosario, quien vivió en los años que dieron nacimiento a la República de Colombia. Se desempeñó como cura revolucionario, como político de Mompós, de Cartagena de Indias, ante el Congreso de las Provincias Unidas del Congreso Nacional...

  12. Paloma Fernández Gomá: latidos de poesía que unen orillas

    OpenAIRE

    Medrano, Susana de los Ángeles

    2010-01-01

    En la lírica española contemporánea ya no cabe duda de que la poesía de mujer constituye un aporte significativo. Dentro de su entramado, en la panorámica actual de la lírica femenina de Andalucía, Paloma Fernández Gomá se perfila como una de las poetas más interesantes y singulares. Nacida en Madrid y asentada en Algeciras (Cádiz) desde niña, su poesía se inicia tempranamente pero recién se da a conocer en 1991 con El ocaso del girasol, al que le siguen hasta el momento una decena de poemari...

  13. THE EFFECT OF Anredera cordifolia (Ten. Steenis SUPPLEMENTATION ON UTERINE INVOLUTION PROCESS EVALUATED BY OESTRUS POST PARTUM BEHAVIOR AND FERNING

    Directory of Open Access Journals (Sweden)

    R. Purwasih

    2014-09-01

    Full Text Available The aim of this study was to determine the effect of Anrederacordifolia (Ten. Steenissupplementation on uterine involution process in rabbit. The research design applied was completelyrandomized design with 4 treatments and 3 replications (T0 = without Anredera cordifoliasupplementation; TI = Anredera cordifolia supplemented two days before parturition; T2 = Anrederacordifolia supplemented two days after parturition; T3 = Anredera cordifolia supplemented two daysbefore until two days after parturition. The results showed that Anredera cordifolia (Ten. Steenissupplementation could accelerate post partum oestrus in does that were characterized by post partumoestrus behavior, ferning of saliva and cervical mucus. The best treatment was T3, that was four daysAnredera cordifolia supplementation that was administered at 0.45 g/kg of body weight/day. Furtherresearch was needed to find an optimal dose of Anredera cordifolia (Ten. Steenis on uterine involution.

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

    Science.gov (United States)

    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.

  15. Rock paintings in Fern Cave, Lava Beds National Monument, California: Not the 1054 A.D. (Crab Nebula) Supernova

    International Nuclear Information System (INIS)

    Armitage, R.A.; Hyman, M.; Rowe, M. W.

    1997-01-01

    On July 4, 1054 A.D. a supernova brighter than Venus appeared in the sky, remaining visible for approximately 23 days and 650 nights. It was chronicled in five independent historic accounts, four in China and one in Japan. For at least 40 years investigators have attributed certain distinctive rock paintings and carvings in the western United States as recordings of the 1054 A.D. supernova. More than twenty such depictions (circle or star-like symbols and a crescent) have been located. Two panels of rock paintings in Lava Beds National Monument, California, one at Fern Cave and one at Symbol Bridge, were listed as recording the 1054 A.D. supernova. The only direct means of assessing the likelihood that a 'supernova' representation records the 1054 A.D. event is to date the rock painting or carving. At Texas A and M University, was developed a plasma-chemical extraction technique that permits to analyze the 14 C in rock paintings, whether the pigments used were charcoal or inorganic Fe- and Mn- oxides and hydroxides with organic binder/vehicles. This paper presents direct 14 C age estimates on a rock painting suggested to represent the 1054 A.D. supernova. Charcoal pigment samples were collected from three figures in proximity at Fern Cave: a crescent pointing downward and two nearby circles, one above and one below the crescent. The AMS 14 C analysis on each sample using this technique show that these images do not represent the 1054 A.D. supernova

  16. Benito Fernández de Elena Garro: una mirada crítica sobre la historia mexicana

    Directory of Open Access Journals (Sweden)

    Gerardo Bustamante Bermúdez

    2017-07-01

    Full Text Available En 1957, Elena Garro escribió la obra teatral Benito Fernández, texto en el que hace una revisión crítica a la historia nacional, el poder, la simulación y la búsqueda de la identidad personal en medio de la sociedad creada a partir de la posrevolución mexicana. La obra de la escritora es un contradiscurso a la oficialidad, a la mitificación de los hechos y héroes nacionales; lo que le interesa es resaltar el carácter racista y clasista de una nueva sociedad de dirigentes políticos en busca del bienestar personal y de grupo por encima del bien colectivo, para ello, opta porque en su obra los personajes se preocupen por comprar una cabeza, es decir, una ideología que les haga saber que existen. In 1957, Elena Garro wrote the play Benito Fernández, a text in which she critically reviews Mexico's national history, issues of power, simulation and the quest for personal identity in the midst of a society emerged in the after effects of the Mexican Revolution. This work is a counter-discourse to Mexico's official narrative and the idealization of facts and national heroes. She is interested in the racist and classist aspects of the new dominating society, which is interested in their own personal welfare over those of the collective. To do so, she makes her characters concerned about buying a head, that is, an ideology to fundament their own existence.

  17. Proteogenomic Analysis Greatly Expands the Identification of Proteins Related to Reproduction in the Apogamous Fern Dryopteris affinis ssp. affinis.

    Science.gov (United States)

    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.

  18. Sporophyte morphology and gametophyte development of the fern Blechnum sprucei (Pteridophyta: Blechnaceae

    Directory of Open Access Journals (Sweden)

    Jose María Gabriel y Galán

    2008-12-01

    Full Text Available The fern Blechnum sprucei grows in Mesoamerica (Costa Rica and South America, from Colombia to Bolivia, SE and centre of Brazil, Paraguay and Argentina. It is a distinctive, somewhat vulnerable, mostly orophilous species. Fresh and dry herbarium material was used for this study. Herbarium material for anatomical studies comes from CTES, BA, LP, MA, SI and UC (Holmgren et al.1990. Selected representative specimens are additionally cited after taxonomic treatment of the species. Dry material was restored with aqueous 4:1 butil cellosolve. Pinnae were cleared with aqueous 6% NaOH, then coloured with aqueous 1 % TBO (Gurr 1966. Hand made transverse sections of young and adult stipes, and costae were done in fresh and restored herbarium material. Venation and epidermal patterns were analyzed in basal, apical and medium pinnae, but only the latter were illustrated. The size and density of stomata were measured in medium pinnae from all studied samples, values shown are the average of 25 measures per sample; sizes are expressed as minimum, media and maximum length x width, in µm, and density as minimum, media and maximum number of stomata / mm². Spores were studied with SEM, mounted on metal stubs with double sided tape, covered with gold under vacuum and photographed with a Jeol /EO JSM 6360 (15 KV SEM. Spores were also studied with light microscope, mounted in DePex (DePex mounting medium, Gurr, BDH Laboratory Supplies, Poole BH15 1TD, UK and measured using an ocular micrometer. Measurements are based on a minimum sample of 100 spores taken from different specimens. Sizes are expressed as the longest equatorial diameter/ polar diameter, in µm. Gametophytes were studied from material collected in the subtropical forest of Tucumán Province, Argentina. Spore samples for cultures were taken from single sporophytes kept dry at room temperature since the date plants were collected. Gametophytes were grown under fluorescent light. Multispore cultures

  19. Present, past and future of the European rock fern Asplenium fontanum: combining distribution modelling and population genetics to study the effect of climate change on geographic range and genetic diversity.

    Science.gov (United States)

    Bystriakova, Nadia; Ansell, Stephen W; Russell, Stephen J; Grundmann, Michael; Vogel, Johannes C; Schneider, Harald

    2014-02-01

    Climate change is expected to alter the geographic range of many plant species dramatically. Predicting this response will be critical to managing the conservation of plant resources and the effects of invasive species. The aim of this study was to predict the response of temperate homosporous ferns to climate change. Genetic diversity and changes in distribution range were inferred for the diploid rock fern Asplenium fontanum along a South-North transect, extending from its putative last glacial maximum (LGM) refugia in southern France towards southern Germany and eastern-central France. This study reconciles observations from distribution models and phylogeographic analyses derived from plastid and nuclear diversity. Genetic diversity distribution and niche modelling propose that genetic diversity accumulates in the LGM climate refugium in southern France with the formation of a diversity gradient reflecting a slow, post-LGM range expansion towards the current distribution range. Evidence supports the fern's preference for outcrossing, contradicting the expectation that homosporous ferns would populate new sites by single-spore colonization. Prediction of climate and distribution range change suggests that a dramatic loss of range and genetic diversity in this fern is possible. The observed migration is best described by the phalanx expansion model. The results suggest that homosporous ferns reproducing preferentially by outcrossing accumulate genetic diversity primarily in LGM climate refugia and may be threatened if these areas disappear due to global climate change.

  20. La poética de la Nocilla: Transmedia Poetics in Agustín Fernández Mallo’s Complete Works.

    Directory of Open Access Journals (Sweden)

    Alex Saum-Pascual

    2014-06-01

    Full Text Available Moving beyond current applications of transmedia storytelling, this essay looks at the work of Spanish author Agustín Fernández Mallo to explore how his engagement with the media landscape is both a revolution and a contribution to fundamental concepts in contemporary literature such as authorship and narrative structure. On the one hand, transmedia storytelling provides a structure to frame Fernández Mallo’s versatile and multimedia production, exploring both the productive semiotic intermedial breakages within works, as well as analyzing his complete production as a whole: one single poetic “work” encapsulated into a transmedia universe composed of multiple autonomous narratives. On the other, the fictionalization of his Author function as a parodied metafictional object within this transmedia universe can shed some light on the role of the writer within a larger network of media convergence and neoliberal enterprises.

  1. Mesobathic chondrichthyes of the Juan Fernández seamounts: are they different from those of the central Chilean continental slope?

    Directory of Open Access Journals (Sweden)

    Isabel Andrade

    2008-03-01

    Full Text Available We compared the geographic distribution of groups of chondrychthid fishes of two physically proximal, although geographically different, regions that include the Juan Fernández seamounts and the central Chilean continental slope, both sampled at mesopelagic and mesobenthonic depths. The ridge is in the Nazca Plate, while the slope region in on the South American Plate, and is closer to the South American continent. We found six species of Chondrichthyes for the seamounts (four orders, four families. The slope sampling produced ten species of Chondrichthyes, of which Torpedo tremens De Buen 1959, was the only species in common with the Juan Fernández area. There are clear differences between the Chondrichthyes of the two regions. These fisheries require adequate administrative modes. Rev. Biol. Trop. 56 (1: 181-190. Epub 2008 March 31.

  2. Sobre hipermetrías y un estrofa con seis versos en el “Libro de Fernán Gonçález”

    OpenAIRE

    Veiga, Alexandre

    2011-01-01

    El autor reflexiona sobre ciertos versos añadidos a estrofas del Libro de Fernán Gonçález como razonablemente debidos a la intervención de un recitador, de cuya memorización del poema procedería el texto de la única copia que se conserva. El autor procede a la relectura crítica de la estrofa 674/686.

  3. Comparisons of micrometeorology, growth of leather-fern [Rumohra adiantiformis, pteridophyta] and comfortable working environment between PO-film-covered and net-covered greenhouses in summer

    International Nuclear Information System (INIS)

    Yokoyama, H.; Harazono, Y.

    2004-01-01

    Protected cultivation of leather-fern in Hachijo-Island has been urged to prevent the Mottled Yellowing Syndrome (MYS) damage and to reduce the production costs. The purpose of the study was to reveal greenhouse environments that would provide good plant growth, a comfortable working environment and low-cost management, by comparing the micrometeorology and leatherfern productivity between Poly-Olefin (PO) film-covered greenhouses and the conventional netcovered greenhouses. Both greenhouses were fully covered by the same net. Field studies of leather-fern cultivation in Hachijo-Island showed that better productivity and quality of leather-fern have been provided by farmer's net-covered greenhouses than by farmer's PO-covered greenhouses. The light transmittance in the net-covered greenhouse was higher and the air temperature was lower than those in the PO-covered greenhouse. The comparative experiments using PO-covered greenhouses (PO), and net-covered greenhouses (NET), were conducted at the Hachijojima Horticultural Research Center. Air temperature and its vertical gradient in NET were lower than those in PO. Irrigation in PO was 225 mm during August and September in 1999, but 507 mm of precipitation in addition to the irrigation was supplied in NET. Air temperature and its vertical gradient in PO increased with solar radiation increase. Heat disorder in working environments for farmers did not occur in the NET, but several warning hours of heat disorder occurred in the PO as a dangerous working environment. The NET was thought to be a better system of leather-fern cultivation bringing about low costs and comfortable working environments. However, further application of fully rolled-up PO-film greenhouse system was recommended to control the soil water condition

  4. Algunas novelas de Darío Fernández-Flórez: de Zarabanda (1944 a Alta Costura (1954. Temas escabrosos en tiempos de restricciones moralistas

    Directory of Open Access Journals (Sweden)

    Montejo Gurruchaga, Lucía

    2008-06-01

    Full Text Available Dario Fernández-Flórez begins in 1944 with Zarabanda a narrative style of intellectual eroticism and inmoral atmosphere which attracted no attention. Six years later he published Lola, espejo oscuro the recollections of a high prostitute. The novel was an scandal and an immediate success. Although the topic and its treatment were odd at the time because the strict moral values which mantained Franco´s regime were ignored, the novel was published with no cuts at all. Censorship was deaf to all the voices that warned of its dangers. This had an explanation: Darío Fernández-Flórez held an important post in the Propaganda National Service. After his dismissal censors were less lenient.Darío Fernández-Flórez inicia en 1944 con Zarabanda una narrativa de erotismo intelectualizado y ambiente amoral que no tuvo ningún eco. Seis años después publicará Lola, espejo oscuro, las memorias de una prostituta de alto copete. La novela suscitó un gran escándalo y su éxito fue inmediato. Aunque el tema y su tratamiento eran inusitados en aquellos momentos porque la obra daba al traste con los estrictos valores morales que sustentaban el régimen franquista, la novela fue publicada sin recortes; la censura hizo oídos sordos a todas las voces que alertaban de su peligro. Este hecho tiene una explicación: Darío Fernández-Flórez ocupaba un cargo importante en el Servicio Nacional de Propaganda. Tras su cese, los censores serán menos benevolentes.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  7. Richness, geographic distribution and ecological aspects of the fern community within the Murici Ecological Station in the state of Alagoas, Brazil

    Directory of Open Access Journals (Sweden)

    Anna Flora de Novaes Pereira

    2013-12-01

    Full Text Available We conducted a floristic survey of ferns within the Murici Ecological Station (remnant of the northeastern Atlantic Forest, located near the municipalities of Messias and Murici, in the state of Alagoas, Brazil. To increase knowledge of the ferns of Alagoas, we evaluated the species occurring in the study area in terms of richness, composition, geographic distribution, similarities with species in other Brazilian biomes, regional conservation status and ecological aspects. Data were obtained from field work conducted between March 2009 and September 2010. We identified 107 species of ferns, of which 19 represent new records for Alagoas. The richest families were Pteridaceae (29 species and Polypodiaceae (22 species. The richest genera were Adiantum (15 species and Thelypteris (9 species. Most of the species sampled are widely distributed throughout Brazil and the Americas. Within the context of the northeastern Atlantic Forest, 12 species were considered endangered. Concerning the ecological aspects, 88.8% of the species identified were herbaceous, 57.9% were terrestrial and 70.0% occurred in the forest interior.

  8. Mycorrhizal-like interaction between gametophytes and young sporophytes of the fern Dryopteris muenchii (Filicales and its fungal endophyte

    Directory of Open Access Journals (Sweden)

    Irma Reyes-Jaramillo

    2008-09-01

    Full Text Available The morphology of a Glomus-like fungus-host interaction in chlorophyllous gametophytes and young apogamic sporophytes of Dryopteris muenchii A.R. Sm. was studied from ferns cultivated in laboratory, using soil as substrate. An aseptate fungus colonized the gametophytes’ tissue through the rhizoids, developing vesicles. The fungus penetrated the young sporophytes primary roots by developing appressoria. It spread forming inter- and intra-cellular hyphae through the epidermis and the outermost cortical cell layers, where it formed vesicles, hyphal coils-like and arbuscules. The fungus hyphae never colonized the gametophyte-sporophyte cellular junction. The fungal structures observed on D. muenchii during this study, are rather similar to those reported for the plant host-arbuscular mycorrhizal fungus (AMF interaction, where the AMF described belonged to Phylum Glomeromycota. Therefore, this study is a contribution to the scarce knowledgement of the association between AMF and chlorophyllous gametophytes and young apogamic sporophytes of ferns. Rev. Biol. Trop. 56 (3: 1101-1107. Epub 2008 September 30.Se describe la morfología de un hongo endófito afín al género Glomus, como colonizador de gametofitos clorofílicos y de esporofitos apogámicos jóvenes del helecho Dryopteris muenchii A.R. Sm.; el estudio se llevó a cabo con helechos cultivados en el laboratorio y utilizando tierra como substrato. El tejido del gametofito fue colonizado, a través de los rizoides, por un hongo miceliar aseptado, el cual formó vesículas. El hongo logró penetrar las raíces primarias de los esporofitos jóvenes desarrollando apresorios. El hongo se dispersó formando hifas inter- e intra-celulares a través de la epidermis y de la capa de células corticales más externas, donde produjo vesículas, estructuras similares a ovillos y arbúsculos. Las hifas del hongo nunca colonizaron las células de la unión entre el gametofito y el esporofito. Las

  9. A class III chitinase without disulfide bonds from the fern, Pteris ryukyuensis: crystal structure and ligand-binding studies.

    Science.gov (United States)

    Kitaoku, Yoshihito; Umemoto, Naoyuki; Ohnuma, Takayuki; Numata, Tomoyuki; Taira, Toki; Sakuda, Shohei; Fukamizo, Tamo

    2015-10-01

    We first solved the crystal structure of class III catalytic domain of a chitinase from fern (PrChiA-cat), and found a structural difference between PrChiA-cat and hevamine. PrChiA-cat was found to have reduced affinities to chitin oligosaccharides and allosamidin. Plant class III chitinases are subdivided into enzymes with three disulfide bonds and those without disulfide bonds. We here referred to the former enzymes as class IIIa chitinases and the latter as class IIIb chitinases. In this study, we solved the crystal structure of the class IIIb catalytic domain of a chitinase from the fern Pteris ryukyuensis (PrChiA-cat), and compared it with that of hevamine, a class IIIa chitinase from Hevea brasiliensis. PrChiA-cat was found to adopt an (α/β)8 fold typical of GH18 chitinases in a similar manner to that of hevamine. However, PrChiA-cat also had two large loops that extruded from the catalytic site, and the corresponding loops in hevamine were markedly smaller than those of PrChiA-cat. An HPLC analysis of the enzymatic products revealed that the mode of action of PrChiA-cat toward chitin oligosaccharides, (GlcNAc) n (n = 4-6), differed from those of hevamine and the other class IIIa chitinases. The binding affinities of (GlcNAc)3 and (GlcNAc)4 toward the inactive mutant of PrChiA-cat were determined by isothermal titration calorimetry, and were markedly lower than those toward other members of the GH18 family. The affinity and the inhibitory activity of allosamidin toward PrChiA-cat were also lower than those toward the GH18 chitinases investigated to date. Several hydrogen bonds found in the crystal structure of hevamine-allosamidin complex were missing in the modeled structure of PrChiA-cat-allosamidin complex. The structural findings for PrChiA-cat successfully interpreted the functional data presented.

  10. Project "Conservation, Restoration, and Development of the Juan Fernández islands, Chile" Proyecto conservación, restauración y desarrollo de las islas Juan Fernández, Chile

    Directory of Open Access Journals (Sweden)

    JAIME G. CUEVAS

    2001-12-01

    Full Text Available From a scientific point of view, the Juan Fernández islands contain one of the most interesting floras of the planet. Although protected as a National Park and a World Biosphere Reserve, 400 years of human interference have left deep traces in the native plant communities. Repeated burning, overexploitation of species, and the introduction of animal and plant plagues have taken 75 % of the endemic vascular flora to the verge of extinction. In 1997, Chile's national forest service (Corporación Nacional Forestal, CONAF started an ambitious project, whose objective is the recovery of this highly complex ecosystem with a socio-ecological focus. Juan Fernández makes an interesting case, as the local people (600 persons practically live within the park, therefore impeding the exclusion of the people from any conservation program. Secondly, the relatively small size of the archipelago (100 km² permits the observation of the effects of whatever modification in the ecosystem on small scales in time and space. Thirdly, the native and introduced biota are interrelated in such a way that human-caused changes in one species population may provoke unexpected results amongst other, non-target species. The project mainly deals with the eradication or control of some animal and plant plagues, the active conservation and restoration of the flora and the inclusion of the local people in conservation planning. This article presents the park's general problems, the strategy proposed to resolve them as well as some preliminary results. This project shows the complexity of the conservation activities in practice, with diverse and complex interrelations and gaps in ecological knowledge. In this respect, the project may well serve as a model for similar programs in other placesLas islas Juan Fernández albergan una de las floras más interesantes del planeta desde el punto de vista científico. Aunque están protegidas como Parque Nacional y Reserva Mundial de la

  11. Structure of a shear-thickening polysaccharide extracted from the New Zealand black tree fern, Cyathea medullaris.

    Science.gov (United States)

    Wee, May S M; Matia-Merino, Lara; Carnachan, Susan M; Sims, Ian M; Goh, Kelvin K T

    2014-09-01

    A shear-thickening water-soluble polysaccharide was purified from mucilage extracted from the fronds of the New Zealand black tree fern (Cyathea medullaris or 'mamaku' in Māori) and its structure characterised. Constituent sugar analysis by three complementary methods, combined with linkage analysis (of carboxyl reduced samples) and 1H and 13C nuclear magnetic resonance spectroscopy (NMR) revealed a glucuronomannan comprising a backbone of 4-linked methylesterified glucopyranosyl uronic acid and 2-linked mannopyranosyl residues, branched at O-3 of 45% and at both O-3 and O-4 of 53% of the mannopyranosyl residues with side chains likely comprising terminal xylopyranosyl, terminal galactopyranosyl, non-methylesterified terminal glucopyranosyl uronic acid and 3-linked glucopyranosyl uronic acid residues. The weight-average molecular weight of the purified polysaccharide was ∼1.9×10(6) Da as determined by size-exclusion chromatography coupled with multi-angle laser light scattering (SEC-MALLS). The distinctive rheological properties of this polysaccharide are discussed in relation to its structure. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. The rise of the Himalaya enforced the diversification of SE Asian ferns by altering the monsoon regimes

    Directory of Open Access Journals (Sweden)

    Wang Li

    2012-11-01

    Full Text Available Abstract Background The rise of high mountain chains is widely seen as one of the factors driving rapid diversification of land plants and the formation of biodiversity hotspots. Supporting evidence was reported for the impact of the rapid rise of the Andean mountains but this hypothesis has so far been less explored for the impact of the “roof of the world”. The formation of the Himalaya, and especially the rise of the Qinghai–Tibetan Plateau in the recent 20 million years, altered the monsoon regimes that dominate the current climates of South East Asia. Here, we infer the hypothesis that the rise of Himalaya had a strong impact on the plant diversity in the biodiversity hotspot of the Southwest Chinese Mountains. Results Our analyses of the diversification pattern of the derived fern genus Lepisorus recovered evidence for changes in plant diversity that correlated with the strengthening of South East Asian monsoon. Southwest China or Southwest China and Japan was recovered as the putative area of origin of Lepisorus and enhancing monsoon regime were found to shape the early diversification of the genus as well as subsequent radiations during the late Miocene and Pliocene. Conclusions We report new evidence for a coincidence of plant diversification and changes of the climate caused by the uplift of the Himalaya. These results are discussed in the context of the impact of incomplete taxon sampling, uncertainty of divergence time estimates, and limitations of current methods used to assess diversification rates.

  13. Comentarios a las ponencias de Lourenzo Fernández Prieto y Marcela Sabaté Sort

    Directory of Open Access Journals (Sweden)

    Ricardo ROBLEDO HERNÁNDEZ

    2010-02-01

    Full Text Available La ponencia de Lorenzo Fernández Prieto empieza por reivindicar los problemas del presente como punto de partida en la construcción de la historia aconsejando tener en cuenta como referente la crisis del modelo de modernización y el fin de la ideología del progreso. Resulta llamativo que al mismo tiempo, aunque sea de forma marginal, eche una lanza a favor de Fukuyama, tildado habitualmente de ideología conservadora. Pero esto, por decirlo de algún modo, es casi una anécdota puesto que el principal foco de atención es la historia rural como el ámbito más pertinente de historia transnacional. Su ponencia es un alegato más que engrosa la corriente de opinión cada vez más caudalosa en contra de la tesis del fracaso o del excepcionalismo hispánicos. Casi hace treinta años que se está hablando en esta dirección, desde que Martínez Alier y Naredo descartaron que existiera una evolución muy diferente de la agricultura española y que el comportamiento de los grandes labradores o el carácter de las instituciones fueran factores explicativos relevantes en esa supuesta diferenciación.

  14. The Humanist Ideal of Peace in Pacification Accounts by the Chronicler Fernández de Oviedo

    Directory of Open Access Journals (Sweden)

    Vanina María Teglia

    2014-11-01

    Full Text Available This  paper  poses  that,  in  order  to  represent  the  first  Spanish  conquests  in  the Antilles, Gonzalo Fernández de Oviedo, within his Historia General y Natural de las Indias, takes certain official legal documents as models to guide and structure his account. Such documents are the royal ordinances and Palacios Rubios’ Requerimiento.  Consequently,  the  character’s speech  and  actions  are  marked  with  the  ideals  of  XVIth  century  humanist, Renaissance, and erasmist thought —peace, love-friendship  and the model of the prudent, moderate leaders— while a speech which seeks to legitimize the Spanish rules in the New World —while presenting it in terms of «pacification»— is being simultaneously unfolded. This whole discursive compound results in a plural, diverse and at times contradictory account, influenced and influential, and, above all, founding of some of the Utopian-imperial speech and imagery that were projected over the Americas and that constituted it.

  15. Identification guide to Nordic aphids associated with mosses, horsetails and ferns (Bryophyta, Equisetophyta, Polypodiophyta (Insecta, Hemiptera, Aphidoidea

    Directory of Open Access Journals (Sweden)

    Anders Christian Albrecht

    2015-10-01

    Full Text Available Keys and diagnoses of North European aphids (Hemiptera, Aphidoidea associated with mosses, horsetails and ferns are given, based on fresh and freeze-dried material. Numerous externally visible and thus informative characters, that are absent in cleared, slide-mounted specimens, such as body shape colours, wax coating and pattern etc., are utilized. Most of the species are illustrated by photographs of live specimens and drawings. Root-feeding species living in the moss layer or otherwise often present in moss samples are also included, even if their hosts were spermatophytes. The combination of colour images and diagnoses, utilizing easily observed characters, allows the identification of a large number of species already in the field, and many more at home with the aid of a stereo microscope. Host plant relationships and association with ants are summarised, including new records. Brief accounts on aphid life cycles, freeze-drying preparation techniques, etc. are also given to support the use of the keys.

  16. The rise of the Himalaya enforced the diversification of SE Asian ferns by altering the monsoon regimes.

    Science.gov (United States)

    Wang, Li; Schneider, Harald; Zhang, Xian-Chun; Xiang, Qiao-Ping

    2012-11-09

    The rise of high mountain chains is widely seen as one of the factors driving rapid diversification of land plants and the formation of biodiversity hotspots. Supporting evidence was reported for the impact of the rapid rise of the Andean mountains but this hypothesis has so far been less explored for the impact of the "roof of the world". The formation of the Himalaya, and especially the rise of the Qinghai-Tibetan Plateau in the recent 20 million years, altered the monsoon regimes that dominate the current climates of South East Asia. Here, we infer the hypothesis that the rise of Himalaya had a strong impact on the plant diversity in the biodiversity hotspot of the Southwest Chinese Mountains. Our analyses of the diversification pattern of the derived fern genus Lepisorus recovered evidence for changes in plant diversity that correlated with the strengthening of South East Asian monsoon. Southwest China or Southwest China and Japan was recovered as the putative area of origin of Lepisorus and enhancing monsoon regime were found to shape the early diversification of the genus as well as subsequent radiations during the late Miocene and Pliocene. We report new evidence for a coincidence of plant diversification and changes of the climate caused by the uplift of the Himalaya. These results are discussed in the context of the impact of incomplete taxon sampling, uncertainty of divergence time estimates, and limitations of current methods used to assess diversification rates.

  17. Plectranthias lamillai, a new Anthiine fish species (Perciformes, Serranidae from the Juan Fernández Archipelago, Chile

    Directory of Open Access Journals (Sweden)

    José Rodrigo Rojas M.

    1998-09-01

    Full Text Available Plectranthias lamillai new species, is described and illustrated as a new anthiine serranid fish from Alejandro Selkirk Island, the westernmost island of the Juan Fernández Archipelago, about 700 km west of Chile at 33°45´S, 80°51´W. The following combination of characters distinguishes it from all other serranids: dorsal fin rays X,16; principal caudal-fin rays 17 (8+9; pectoral-fin rays 16; gillrakers 28 (8+20; tubed lateral-line scales 40-41; 10 rows of scales on cheek; maxilla narrow and rounded; posterior margin of bony opercle with three spinous processes, the middle one largest; subopercle 2-6 small serrae; pseudobranch with 24 filaments; circumpeduncular scales 16; pelvic fin inserted beneath base of pectoral fin, the tip reaching a vertical through base of tenth dorsal-fin spine, falling short of the anus; a broad red bar from sixth dorsal-fin spine to base of fifth ray, extending to anus and above anal fin as a narrow band that widens on the peduncle and then bifurcates over the upper and lower margins of the caudal fin; rest of the caudal fin yellowish. Pectoral fins orange; pelvic and anal fins whitish.

  18. Responses of the nitrogen-fixing aquatic fern Azolla to water contaminated with ciprofloxacin: Impacts on biofertilization.

    Science.gov (United States)

    Gomes, Marcelo Pedrosa; de Brito, Júlio César Moreira; Carvalho Carneiro, Marília Mércia Lima; Ribeiro da Cunha, Mariem Rodrigues; Garcia, Queila Souza; Figueredo, Cleber Cunha

    2018-01-01

    We investigated the ability of the aquatic fern Azolla to take up ciprofloxacin (Cipro), as well as the effects of that antibiotic on the N-fixing process in plants grown in medium deprived (-N) or provided (+N) with nitrogen (N). Azolla was seen to accumulate Cipro at concentrations greater than 160 μg g -1 dry weight when cultivated in 3.05 mg Cipro l -1 , indicating it as a candidate for Cipro recovery from water. Although Cipro was not seen to interfere with the heterocyst/vegetative cell ratios, the antibiotic promoted changes with carbon and nitrogen metabolism in plants. Decreased photosynthesis and nitrogenase activity, and altered plant's amino acid profile, with decreases in cell N concentrations, were observed. The removal of N from the growth medium accentuated the deleterious effects of Cipro, resulting in lower photosynthesis, N-fixation, and assimilation rates, and increased hydrogen peroxide accumulation. Our results shown that Cipro may constrain the use of Azolla as a biofertilizer species due to its interference with nitrogen fixation processes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Characterization and expression of a metallothionein gene in the aquatic fern Azolla filiculoides under heavy metal stress.

    Science.gov (United States)

    Schor-Fumbarov, Tamar; Goldsbrough, Peter B; Adam, Zach; Tel-Or, Elisha

    2005-12-01

    A cDNA encoding a type 2 metallothionein (MT) was isolated from Azolla filiculoides, termed AzMT2, accession no. AF482470. The AzMT2 transcript was expressed in sterile A. filiculoides that were free of the cyanobiont Anabaena azollae after erythromycin treatment, proving that AzMT2 is encoded by the fern genome. AzMT2 RNA expression was enhanced by the addition of Cd(+2), Cu(+2), Zn(+2) and Ni(+2) to the growth medium. The transcript level of AzMT2 correlated with the metal content in the plants. Temporal analysis of AzMT2 expression demonstrated that Cd(2+) and Ni(2+) induction of AzMT2 RNA expression occurred within 48 h. AzMT2-enhanced expression responded more intensely to the toxic Cd and Ni ions in A. filiculoides suggesting that AzMT2 may participate in detoxification mechanism. The more moderate response of AzMT2 to Zn and Cu ions, which are essential micronutrients, suggest a role for AzMT2 in metal homeostasis.

  20. Pesca artesanal de cangrejo dorado (Chaceon chilensis en el archipiélago de Juan Fernández, Chile Artisanal fishing for golden crab (Chaceon chilensis off the Juan Fernández archipelago, Chile

    Directory of Open Access Journals (Sweden)

    Mauricio Ahumada

    2009-01-01

    Full Text Available Se describe la pesca artesanal de cangrejo dorado (Chaceon chilensis en las islas Robinson Crusoe y Santa Clara, en el archipiélago de Juan Fernández (Chile, desarrollada entre julio de 2005 y mayo de 2006. Se dan a conocer aspectos biológico-pesqueros relativos a esfuerzo y rendimientos de pesca, proporción sexual, así como los resultados de una evaluación directa de biomasa vulnerable mediante el método de area de influencia de las trampas. La extracción se efectuó fundamentalmente en el cuadrante NE de ambas islas, mediante botes de madera de 9,0 m de eslora. Se monitorearon 157 salidas de pesca y se capturaron 13.903 ejemplares, los cuales mayoritariamente fueron machos (97,5%. La CPUE promedio fue 16,7 ejemplares por trampa y de 13,5 ejemplares comerciales por trampa. A partir del muestreo sistemático, se detectó al recurso entre 300 y 1000 m de profundidad, con mayores rendimientos entre 400 y 500 m de profundidad (19,8 y 15,9 ejemplares por trampa. Se consideran y discuten dos escenarios de evaluación de stock para ejemplares de talla comercial en el area actualmente explotada (45,8 km , el primero estimó un radio efectivo para las trampas de 13,4 m (area de 564,1 m , con una biomasa vulnerable de 1.002 ton, equivalentes a 832.983 ejemplares, mientras que el segundo consideró un radio de 30,0 m con una biomasa vulnerable de 203 ton equivalente a 168.587 ejemplares.This work describes the artisanal golden crab (Chaceon chilensis fishery off Robinson Crusoe and Santa Clara islands in the Juan Fernández archipelago (Chile developed between July 2005 and May 2006. We report biological fishery aspects related to the físhing efforts and yields, the sexual proportion of the catch, and the results of a direct evaluation of the vulnerable biomass done using the trap area of influence method. The extraction was done mainly in the NE quadrant of both islands from wooden boats (9.0 m length. Monitoring was done during 157 f

  1. What is Scirrhia?

    NARCIS (Netherlands)

    Crous, P.W.; Minnis, A.M.; Pereira, O.L.; Alfenas, A.C.; Alfenas, R.F.; Rossman, A.Y.; Groenewald, J.Z.

    2011-01-01

    The ascomycetous genus Scirrhia is presently treated as a member of Dothideomycetidae, though uncertainty remains as to which family it belongs in Capnodiales, Ascomycota. Recent collections on stems of a fern, Pteridium aquilinum (Dennstaedtiaceae) in Brazil, led to the discovery of a new species

  2. What is Scirrhia?

    NARCIS (Netherlands)

    Crous, P.W.; Minnis, A.M.; Pereira, O.L.; Alfenas, A.C.; Alfenas, R.F.; Rossman, A.Y.; Groenewald, J.Z.

    2011-01-01

    The ascomycetous genus Scirrhia is presently treated as a member of Dothideomycetidae, though uncertainty remains as to which family it belongs in Capnodiales, Ascomycota. Recent collections on stems of a fern, Pteridium aquilinum {Dennstaedtiaceae) in Brazil, led to the discovery of a new species

  3. The cation-controlled and hydrogen bond-mediated shear-thickening behaviour of a tree-fern isolated polysaccharide.

    Science.gov (United States)

    Wee, May S M; Matia-Merino, Lara; Goh, Kelvin K T

    2015-10-05

    The shear-thickening rheological behaviour (between 5 and 20s(-1)) of a 5% (w/w) viscoelastic gum extracted from the fronds of the native New Zealand black tree fern or mamaku in Māori was further explored by manipulating the salt content. The freeze-dried mamaku gum contained a high mineral content and sugars which upon removal via dialysis, resulted in the loss of shear thickening. However, this loss was reversible by the addition of salts to the dialysed dispersion. The mechanism of shear-thickening behaviour was therefore hypothesised to be due to shear-induced transition of intra- to intermolecular hydrogen bonding, promoted by the screening effect of cations. Mono-, di- and trivalent salts, i.e. Na(+), K(+), N(CH3)4(+), Ca(2+), Mg(2+), Al(3+) and La(3+) at concentrations between 0.001 and 1.0M were tested to support the hypothesis as well as to demonstrate the sensitivity of the biopolymer to cation valency and concentrations. The cation valency and concentration were crucial factors in determining: (i) zero-shear viscosity, (ii) critical shear rate, γ˙c (or shear rate at the onset of shear-thickening) and (iii) the extent of shear-thickening of the solution. For mono- and divalent cations these parameters were similar at equivalent ionic strengths and fairly independent of the cation type. Trivalent cations (La(3+)) however caused precipitation of the gum in the concentration range of 0.005-0.05 M but clear dispersions were obtained above 0.05 M. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Overcoming deep roots, fast rates, and short internodes to resolve the ancient rapid radiation of eupolypod II ferns.

    Science.gov (United States)

    Rothfels, Carl J; Larsson, Anders; Kuo, Li-Yaung; Korall, Petra; Chiou, Wen-Liang; Pryer, Kathleen M

    2012-05-01

    Backbone relationships within the large eupolypod II clade, which includes nearly a third of extant fern species, have resisted elucidation by both molecular and morphological data. Earlier studies suggest that much of the phylogenetic intractability of this group is due to three factors: (i) a long root that reduces apparent levels of support in the ingroup; (ii) long ingroup branches subtended by a series of very short backbone internodes (the "ancient rapid radiation" model); and (iii) significantly heterogeneous lineage-specific rates of substitution. To resolve the eupolypod II phylogeny, with a particular emphasis on the backbone internodes, we assembled a data set of five plastid loci (atpA, atpB, matK, rbcL, and trnG-R) from a sample of 81 accessions selected to capture the deepest divergences in the clade. We then evaluated our phylogenetic hypothesis against potential confounding factors, including those induced by rooting, ancient rapid radiation, rate heterogeneity, and the Bayesian star-tree paradox artifact. While the strong support we inferred for the backbone relationships proved robust to these potential problems, their investigation revealed unexpected model-mediated impacts of outgroup composition, divergent effects of methods for countering the star-tree paradox artifact, and gave no support to concerns about the applicability of the unrooted model to data sets with heterogeneous lineage-specific rates of substitution. This study is among few to investigate these factors with empirical data, and the first to compare the performance of the two primary methods for overcoming the Bayesian star-tree paradox artifact. Among the significant phylogenetic results is the near-complete support along the eupolypod II backbone, the demonstrated paraphyly of Woodsiaceae as currently circumscribed, and the well-supported placement of the enigmatic genera Homalosorus, Diplaziopsis, and Woodsia.

  5. Plate tectonics and the origin of the Juan Fernández Ridge: analysis of bathymetry and magnetic patterns

    Directory of Open Access Journals (Sweden)

    Cristián Rodrigo

    2014-10-01

    Full Text Available Juan Fernández Ridge (JFR is a cα. 800 km long alignment of seamounts and islands which is thought to be fed by a deep mantle plume. JFR includes the Friday and Domingo seamounts in the western active edge close to the active hotspot, and the O'Higgins Seamount and Guyot at the eastern limit just in front of the Chile-Perú trench. Recent bathymetric (Global Topography and magnetic (EMAG-2 datasets were interpreted both qualitatively and quantitatively by means of 3D inverse modeling and 2D direct modeling for geometry and susceptibility, together with an interpretation of the synthetic anomalies related to the classical hypothesis of deep seafloor spreading. Topographic and magnetic patterns are used to understand the tectonic evolution and origin of the JFR, especially in the western segment. Results show a continuous corridor with a base at ~3900 m depth formed by four groups of seamounts/islands with a number of summits. The deep ocean floor is ~22 to ~37 Myr old and is younger to the south of the Challenger Fracture Zone that runs in a SW-NE direction. The magnetic pattern of the western JFR segment, which is different than the eastern one, has no correlation with bathymetry and does not present a common polarity nor fit with magnetic models for isolated bodies. This superposition of magnetic patterns indicates a role of the faults/fractures of the Nazca Plate. Geological evidence supports the hypothesis of a fixed mantle plume for the origin of JFR but our data suggest that tectonic processes play a role, thus fueling the global controversy about these competing processes.

  6. The Relationship Between Tear Ferning Patterns and Non-invasive Tear Break-up Time in Normal Asian Population.

    Science.gov (United States)

    Sharanjeet-Kaur; Ho, Chien Yee; Mutalib, Haliza Abdul; Ghazali, Ahmad Rohi

    2016-01-01

    To investigate the relationship between tear ferning patterns (TFP) and non-invasive tear break-up time (NIBUT) in normal Asian subjects. One hundred and forty-five adults with no ocular surface disorders were recruited. TFP and NIBUT were determined. Tears were collected using a capillary tube and allowed to air dry at room temperature for 10min. TFP was later observed using a light microscope and classified according to Rolando's classification. Measurement for NIBUT was obtained using a Tearscope with the slit lamp magnification. It was found that there is no significant difference between gender in TFP (Z=-1.77, P>.05) and NIBUT (Z=-1.475, P>.05). There is also no significant difference between Malay, Chinese, Indian, and other races in TFP, (H(3)=4.85, P>.05) and NIBUT (H(3)=2.18, P>.05). However, there is a significant difference between age groups of 20-29, 30-39, 40-49,and 50-60 years old in both TFP (H(3)=28.25, P<.01) and NIBUT (H(3)=36.50, P<.001). Spearman's correlation showed there was a significant relationship between TFP and NIBUT (r=-0.55, P<.001), age and NIBUT (r=-0.50, P<.001), age and TFP (r=0.41, P<.001), McMonnies score and NIBUT (r=-0.40, P<.001), McMonnies score and TFP (r=0.31, P<.001), as well as age and McMonnies score (r=0.52, P<.001). TFP and NIBUT was age dependent but not gender and race dependent. Older subjects had higher grade of TFP and McMonnies questionnaire score but lower NIBUT value. TFP and NIBUT can be used to assess the tear film quality. Copyright © 2015 Spanish General Council of Optometry. Published by Elsevier Espana. All rights reserved.

  7. Autobiografía y memoria en el diario de viajes del VI Conde de Fernán Núñez = Autobiography and Memory in the Travel Diary of the VI Count of Fernán Núñez

    Directory of Open Access Journals (Sweden)

    Carolina Blutrach

    2016-12-01

    Full Text Available ResumenEl viaje fue una constante en la vida de don Carlos José Gutiérrez de los Ríos, VI conde de Fernán Núñez (1742-1795. A través de ellos pudo cumplir con su servicio al rey y con sus responsabilidades como cabeza del linaje. Asimismo pudo completar su formación y satisfacer anhelos más personales. De todos sus viajes, los realizados dentro y fuera de España, guardó memoria escrita en un diario de viajes, un documento que, en formato manuscrito, se conservó en su archivo familiar. En un periodo cronológico en el que el viaje y su relato adquirieron especial protagonismo, este trabajo analiza el papel que el viaje jugó en la vida y memoria del VI conde de Fernán Núñez y su impronta dentro del linaje.AbstractTravelling had a constant presence in the life of don Carlos José Gutiérrez de los Ríos, VI Count of Fernán Núñez (1742-1795. Through them he could fulfil his service to the king and his responsibilities as head of the lineage. He could also complete his training and meet more personal yearnings. Of all his travels, the ones he made in and out of Spain, he kept a record in his Travel Diary, which was preserved as a manuscript in the family archive. In a period in which travelling and its written memory gained special prominence, this paper analyses the role it played in the life and memory of the VI Count of Fernán Núñez and its mark within the lineage.

  8. The fossil Osmundales (Royal Ferns)-a phylogenetic network analysis, revised taxonomy, and evolutionary classification of anatomically preserved trunks and rhizomes.

    Science.gov (United States)

    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

  9. The fossil Osmundales (Royal Ferns)—a phylogenetic network analysis, revised taxonomy, and evolutionary classification of anatomically preserved trunks and rhizomes

    Science.gov (United States)

    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

  10. Imaging of metal bioaccumulation in Hay-scented fern (Dennstaedtia punctilobula) rhizomes growing on contaminated soils by laser ablation ICP-MS

    International Nuclear Information System (INIS)

    Koelmel, Jeremy; Amarasiriwardena, Dulasiri

    2012-01-01

    Understanding Pb removal from the translocation stream is vital to engineering Pb hyperaccumulation in above ground organs, which would enhance the economic feasibility of Pb phytoextraction technologies. We investigated Cu, Pb, Sb and Zn distributions in Hay-scented fern (Dennstaedtia punctilobula) rhizomes on shooting range soils by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS), analyzing digested rhizomes, stems, and fronds using ICP-MS. Nutrients Cu and Zn concentrated in fronds while toxic elements Pb and Sb did not, showing potential Pb and Sb sequestration in the rhizome. Frond and rhizome concentration of Pb was 0.17 ± 0.10% and 0.32 ± 0.21% of dry biomass, respectively. The 208 Pb/ 13 C and 121 Sb/ 13 C determined by LA-ICP-MS increased from inner sclerotic cortex to the epidermis, while Pb concentrated in the starchy cortex only in contaminated sites. These results suggest that concentration dependent bioaccumulation in the rhizome outer cortex removes Pb from the vascular transport stream. - Highlights: ► Bioimaged Cu, Pb, Sb, Zn across fern rhizomes from shooting ranges using LA-ICP-MS. ► Pb levels were highest in the outer starchy cortex. ► Pb seemed to displace nutrients Cu and Zn in contaminated site rhizomes. ► [Pb] and [Sb] were correlated across organs suggesting similar transport factors. - Using LA-ICP-MS we determined elemental distributions in Hay-scented fern rhizomes including concentration dependent Pb sequestration patterns in the outer cortex.

  11. A comparison of the dietary arsenic exposures from ingestion of contaminated soil and hyperaccumulating Pteris ferns used in a residential phytoremediation project.

    Science.gov (United States)

    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.

  12. Identification of up-regulated genes from the metal-hyperaccumulator aquatic fern Salvinia minima Baker, in response to lead exposure.

    Science.gov (United States)

    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.

  13. 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.

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

  15. Ciclo anual de la clorofila-α satelital en el archipiélago de Juan Fernández (33°S), Chile

    OpenAIRE

    Andrade,Isabel; Hormazabal,Samuel E; Correa-Ramirez,Marco A

    2012-01-01

    La variabilidad espacial y temporal del ciclo anual de la clorofila-α en el archipiélago de Juan Fernández se analiza usando ocho anos de datos satelitales de clorofila-α, viento, corrientes y nivel del mar. Este archipiélago está conformado por tres islas: Robinson Crusoe-Santa Clara (RC-SC) y Alejandro Selkirk (AS). Las islas RC-SC se encuentran en una región de alta energía cinética y mayores concentraciones de clorofila-α definida como Zona de Transición Costera, en cambio ...

  16. Ability of the aquatic fern Azolla to remove chemical oxygen demand and polyphenols from olive mill wastewater

    Directory of Open Access Journals (Sweden)

    Sacchi, Angelo

    2007-03-01

    Full Text Available We investigated the biofiltration ability of the aquatic fern Azolla to remove polyphenols and chemical oxygen demand (COD from olive mill wastewater (OMWw collected from the traditional (TS and continuous (CS extraction systems. Azolla biomass was packed into five sequential Imhoff cones and five sequential columns. In both experiments, the filtrates collected from the 5th biofilter showed a decrease in polyphenol contents: from 7650 mg l–1 to 3610 mg l–1 in TS OMWw and from 3852 mg l–1 to 1351 mg l–1 in CS OMWw. The COD contents decreased from 110200 mg L–1 to 52400 mg L–1 in TS OMWw and from 41600 mg L–1 to 2300 mg L–1 in CS OMWw. A 5:1 OMWw to Azolla-fresh-weight ratio was optimal for both polyphenol and COD removal. The biofiltration ability of alfalfa was compared with that of Azolla, but the treatment with alfalfa did not result in the reduction of COD or polyphenols.La eficacia del helecho de agua azolla para eliminar polifenoles y reducir la demanda química de oxígeno (DQO de los alpechines obtenidos en el proceso de obtención tradicional y continuo del aceite de oliva, fue investigado mediante ensayos de filtración. Cinco conos secuenciales de Imhoff y cinco columnas secuenciales se rellenaron de biomasa de Azolla. En ambos experimentos, el filtrado procedente de la quinta extracción mostró una disminución en el contenido de polifenoles de 7650 mg L–1 a 3610 mg L–1en el alpechín obtenido mediante el sistema tradicional y de 3852 mg L–1 a 1351 mg L–1en el alpechín del sistema continuo. La demanda química de oxígeno del alpechín del sistema tradicional disminuyó de 110200 mg L–1 a 52400 mg L–1 en y de 41600 mg L–1a 2300 mg L–1en el procedente del sistema continuo. Una proporción en peso 5:1 de alpechín: Azolla fue la óptima tanto para la reducción de los polifenoles como para la de la DQO. La eficiencia del tratamiento biológico con alfalfa se comparó con la obtenida con Azolla. Los

  17. Growth dynamics of fine roots in a coniferous fern forest site close to Forsmark in the central part of Sweden

    International Nuclear Information System (INIS)

    Persson, Hans; Stadenberg, Ingela

    2007-12-01

    The seasonal growth dynamics of live and dead roots for trees and the field layer species (g/m 2 , varying diameter fractions) and live/dead ratios were analysed at a fresh/moist coniferous fern forest site close to the nuclear power plant at Forsmark in the central eastern parts of Sweden. The changes in depth distribution of fine roots were observed at depth intervals of the top humus horizon down to 40 cm in the mineral soil profile. The bulk of living fine roots of trees ( 2 . The total quantity of fine roots (live + dead) amounted to 543, 434, 314 and 546 g/m 2 . Considerable quantities of fine roots (< 1 mm in diameter) were attributed to field-layer species (about 18% of the total biomass during the whole period of investigation). The turnover rate (the rate of construction of new roots) for tree fine roots < 1 mm in diameter amounted to at least the size of the average fine-root biomass. Our methods of estimating fine-root production and mortality, involved periodic measurements of live and dead dry weight of the fine roots from sequential core samples of the forest soil. The collected data give a proper and instant measure of the spatial and temporal distribution of fine roots in the undisturbed soil-profile. Data from other fine-root investigations suggest turnover rates in agreement with our present findings. Differences between root growth and turnover should be expected between trees of different age, tree species and different forest sites, but also between different years. Substantial variations in fine-root biomass, necromass and live/dead ratios are found in different forest sites. Correct methods for estimating the amount of live and dead fine-roots in the soil at regular time intervals are essential for any calculation of fine-root turnover. Definition of root vitality differs in literature, making it difficult to compare results from different root investigators. Our investigation clarifies the importance of using distinct morphological criteria

  18. Proteomic analysis of stipe explants reveals differentially expressed proteins involved in early direct somatic embryogenesis of the tree fern Cyathea delgadii Sternb.

    Science.gov (United States)

    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.

  19. 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.

    Science.gov (United States)

    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.

  20. LA PALABRA DIBUJADA. ANTONIO FERNÁNDEZ-ALBA, PRIMER Y ÚLTIMO MAESTRO / The drawn word. Antonio Fernández-Alba, first and last master

    Directory of Open Access Journals (Sweden)

    Juan Luis Trillo de Leyva

    2015-05-01

    Full Text Available Távora y Fernández-Alba son figuras de referencia ineludible para quienes quieran hoy investigar el origen contemporáneo de la arquitectura peninsular y, sobre todo, de sus escuelas. Alba fue siempre una guía para los que abordamos una enseñanza alejados del aura que acompañaba a los grandes arquitectos madrileños y barceloneses. Su experimentación didáctica alteró la trayectoria de las escuelas de arquitectura españolas. Introdujo la cultura contemporánea en la universidad como si se tratara de una segunda naturaleza, de un nuevo estrato territorial de los proyectos, manteniendo al hombre como objeto central y destinatario de todo proceso proyectual. En época de virtualidad y representación automatizada, nada más adecuado que la revisión de los dibujos del maestro Fernández-Alba. Dibujos que requieren ser proyectados, pensados, antes que ejecutados, “proyectos de proyectos”, una especie de tautología que rige la mente del poeta en su continua reducción, compresión o destilación, gota a gota, del mundo real, del universo y la palabra.

  1. μ-XRF imaging and μ-XANES analysis of root of arsenic hyperaccumulator fern (Pteris vittata L.) by using synchrotron radiation

    International Nuclear Information System (INIS)

    Kitajima, Nobuyuki; Onuma, Ryoko; Hokura, Akiko; Nakai, Izumi; Terada, Yasuko

    2006-01-01

    Pteris vittata L. is known as a peculiar fern which have high performance to accumulate arsenic, a toxic heavy metal, in its plant body. This fern is expected as a strong candidate plant for a technology of phytoremediation due to its hyperaccumulation ability (over 2% arsenic concentration with dry weight basis). In this study, the distribution of arsenic in a horizontal cross-section of root was examined by μ-SR-XRF imaging, and a valence change from surface to centre of the root was revealed by the As-K edge μ-XANES spectra. All the measurements were carried out utilizing X-ray microbeam (1.1 μm x 1.3 μm) from the undulator source at BL37XU in SPring-8 (JASRI, Japan). Arsenic was detected on whole area of root tissue from surface to centre, and mainly distributed within the structure through a cell wall. A comparison of XANES spectra of the 8 points in the root tissue at high As level with those of the reference compounds (As 2 O 3 and H 3 AsO 4 ), revealed that As (V) uptaken by root was reduced to As (III) immediately, and existed as a mixture of As (III) and As (V). Furthermore, it was indicated that their ratios As (III)/As (V) increased remarkably at the boundary area between the cortex and the central cylinder. (author)

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

    Science.gov (United States)

    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.

  3. New additions to the introduced flora of the Juan Fernández Islands: origin, distribution, life history traits, and potential of invasion Nuevas adiciones a la flora introducida de las Islas Juan Fernández: origen, distribución, rasgos de historia de vida y potencial de invasión

    Directory of Open Access Journals (Sweden)

    JAIME G. CUEVAS

    2004-09-01

    Full Text Available Oceanic islands, such as Juan Fernández in Chile, are the home for particular biotas that have evolved in isolation over a long period. The anthropogenic introduction of allochtonous plants is one of many problems for the conservation of endemic elements. In this paper, we present the new additions to the introduced flora of the Juan Fernández Islands, adding some comments about their life form, origin, morphological characteristics, ecology, distribution, abundance, and their potential of invasion. We cited 27 new species, 12 new genera, and three new families for the Juan Fernández flora (Amaryllidaceae, Commelinaceae and Violaceae. Most genera belonged to Asteraceae (seven species. Fifty-nine percent of taxa were perennial herbs, followed by annual or biennial herbs. Wind was the main vector of propagule dispersal (42 %, followed by vegetative dispersal (23 %. Fifty-two percent of the species were weeds and 44 % were plants with dual behaviour: garden-weed plant. Eurasia was the most frequent area of plant origin (70 %. Ninety-four percent of the taxa with known geographic range are in the V Region of mainland Chile, which is the main region of export of plants and materials to the archipelago, suggesting that this may have been the immediate origin of these introductions. Sixty-three percent of the species were only found in the San Juan Bautista urban area, while the remaining taxa were also (22 % or exclusively (15 % found in other places of the main island (Robinson Crusoe. Sixteen species (59 % are considered as noxious weeds in Juan Fernández or elsewhere, and they should be a focus of attention and, eventually, control. Summing our findings to previous lists of introduced taxa, we obtained 260 non-native taxa in Juan Fernández. This number is greater than the native taxa (211, which demonstrate how the human intentional and non-intentional action can dramatically change the floristic composition of an oceanic archipelago. We

  4. Cultivo de Cattleya Lindley (Orchidaceae em substratos alternativos ao xaxim = Alternative substrates for Cattleya (Orchidaceae cultivation to substitute the tree fern fiber

    Directory of Open Access Journals (Sweden)

    Jorge Kaoro Yamakami

    2006-10-01

    Full Text Available Este trabalho teve como objetivo avaliar substratos alternativos ao xaxim no cultivo de um híbrido de Cattleya Lindley. Os substratos avaliados foram: xaxim; fibra de coco; casca de pínus + casca de arroz carbonizada (1:1v/v; casca de pínus+casca de arroz carbonizada (2:1v/v; casca de pínus+casca de arroz carbonizada (1:2v/v; casca de pínus e casca de arroz carbonizada. As mudas foram cultivadas em vasos de polipropileno, permanecendo em viveiro com 70% de luminosidade Os parâmetros avaliados um ano após o início do experimento foram: massa de matéria fresca total, altura da parte aérea, comprimento do pseudobulbo, comprimento da maior raiz, número de raízes, número de brotos, número de flores, pH e condutividade elétrica. O substrato constituído de fibra de coco proporcionou bons resultados, podendo ser considerado alternativo ao xaxim no cultivo deCattleya.The objective of this study was to evaluate alternative substrates tosubstitute tree fern fiber for cultivation of hybrids from the Cattleya species. Seedlings were cultivated in polypropylene vases, kept in screen shadowed nursery by a 70% of lighting. The following substrates were evaluated: tree fern fibers; coconut fiber; pinus bark+carbonized rice hull (1:1 v/v; pinus bark+carbonized rice hull (2:1 v/v; pinus bark+carbonized rice hull (1:2 v/v; pinus bark and carbonized rice hull. One year after the experiment, the followingparameters were evaluated: fresh matter mass, aerial part height, pseudobulb length, greater root length, number of buds, number of flowers, pH and electric conductivity. The substrate composed of coconut fiber showed better results, and can be used as the alternative substrate to tree fern fiber in the cultivation of Cattleya.

  5. Substratos alternativos ao xaxim na produção de bromélia ornamental Alternative substrates to fern tree fiber in the production of ornamental bromeliad

    Directory of Open Access Journals (Sweden)

    Shoey Kanashiro

    2008-10-01

    Full Text Available O objetivo deste trabalho foi avaliar substratos alternativos para o cultivo da bromélia Aechmea fasciata (Lindley Baker, para substituir com eficiência as misturas formuladas com o xaxim Dicksonia sellowiana (Presl. Hook. Foram testados os substratos: casca de Pinus, casca de Eucalyptus, coxim, fibra de coco e xaxim, misturados com turfa e perlita, nas proporções 2:7:1, 5:4:1 e 8:1:1. O experimento foi realizado em condições de estufa com cobertura de polietileno, sombreada com tela a 70%. As bromélias foram cultivadas durante 435 dias, até o início do florescimento - estádio de comercialização. As variáveis analisadas foram as massas de matéria seca de: folhas, raiz, inflorescência, escapo floral e caule; além da massa de matéria seca total e a qualidade comercial. Os substratos formulados com xaxim ou casca de Pinus, nas proporções 2:7:1, 5:4:1 e 8:1:1, e com casca de Eucalyptus, fibra de coco ou coxim, na proporção 2:7:1, foram as misturas que apresentaram os melhores resultados. Os substratos formulados com casca de Eucalyptus, fibra de coco ou coxim, com 10% de turfa e 10% de perlita, na proporção 8:1:1, apresentaram os piores resultados.The objective of this study was to evaluate alternative substrates for the cultivation of the bromeliad Aechmea fasciata (Lindley Baker, to substitute the formulated mixtures with fern tree fiber from Dicksonia sellowiana (Presl. Hook. Tested substrates were: Pinus bark, Eucalyptus bark, coxim (made of coconut fiber, coir or fern tree fiber, mixed with peat and perlite, in the proportions 2:7:1, 5:4:1 and 8:1:1. The experiment was conducted in a greenhouse covered with polyethylene and shaded with shade cloth 70%. The bromeliads were cultivated during 435 days, until the beginning of the flowering, when they were suitable for commercialization. The evaluated parameters were dry masses of leaf, root, inflorescence, floral scape, and stem, besides total dry mass and the commercial

  6. Survey of ferns and clinico-pathological studies on the field cases of Enzootic bovine haematuria in Himachal Pradesh, a north-western Himalayan state of India

    DEFF Research Database (Denmark)

    Rai, Sarvesh K.; Sharma, Rinku; Kumari, Alka

    2017-01-01

    Enzootic bovine haematuria (EBH) in cattle occurs in upland areas of the world. In India, the disease is present in isolated pockets in the Himalayas and in the Nilgiri Hills. The variation in the disease incidence has been attributed to different environmental conditions and animal rearing pract...... bladder tissue, the field case was diagnosed as transitional cell adenocarcinoma with chronic lymphocytic cystitis.......B) in some of the ferns collected from Kullu and Chamba regions ranged from 0 to 358.6 ± 70.5 μg/g and 0 to 652.4 ± 50.0 μg/g, respectively. In addition, field cases of the disease in cattle were also studied in the EBH endemic districts. A total of sixteen cattle urine samples and one urinary bladder of EBH...

  7. Innovation in hydroelectric power plant design in early twentieth century. Casto Fernández-Shaw's Engineering Architecture in La Jándula dam

    Directory of Open Access Journals (Sweden)

    A. B. Berrocal Menárguez

    2017-09-01

    Full Text Available The power plant location in the first hydroelectrial dams was a relevant issue at the end of XIX century and early XX. Different solutions were tried, some of them with very interesting aesthetics results and hydraulic and structural implications. Such is the case of La Jándula dam, inaugurated in 1930, that includes the power station inside the dam. This article examines the possible national and international inspirations of this singular solution, corroborating the hypothesis of its unprecedented nature. The collaboration of the architect Casto Fernández-Shaw in the design and integration of the engine room was decisive, because it achieved a result of an aesthetic quality and formal expressiveness unprecedented in a work of hydraulic engineering, as well as the birth of a style Shaw himself defined as architectural engineering.

  8. El primer registro de Simón Fernández de Moya, escribano público de Cuenca. 1423

    Directory of Open Access Journals (Sweden)

    Francisco Antonio Chacón Gómez-Monedero

    2005-01-01

    Full Text Available El estudio y publicación de los registros notariales de la Edad Media proporciona interesante información sobre aspectos sociales de los habitantes de cualquier población. En este trabajo estudiamos el primer registro que confeccionó el escribano Simón Fernández de Moya, investido de la «fieles pública» por el Concejo de Cuenca en sesión municipal de 7 de mayo de 1423. Se presta especial atención a los dos aspectos básicos que interesan al diplomatista: el de los caracteres externos e internos, según la tipología diplomática de los negocios que fedata el «auctor». Ante la imposibilidad material de transcribir el Registro hemos optado por regestar los asientos, acompañados de un índice onomástico.The publication of the present article shows the importance of notarial records in the Middie Ages and how they provide interested Information about social issues of the inhabitants of whichever town. On this review, it is studied the first record elaborated by Simón Fernández de Moya who was invested with «fieles publica» by the Council of Cuenca at municipal session on 7th May 1423. Two aspects can be taken into account by the diplomatist: the external and the infernal characters according to the typificatlon of Diplomatic about business. Because of the material imposibility to transcribe completely the record book, the present essay only summarize all seats as well as an Índex of ñames.

  9. A plastid phylogeny and character evolution of the Old World fern genus Pyrrosia (Polypodiaceae) with the description of a new genus: Hovenkampia (Polypodiaceae).

    Science.gov (United States)

    Zhou, Xin-Mao; Zhang, Liang; Chen, Cheng-Wei; Li, Chun-Xiang; Huang, Yao-Moan; Chen, De-Kui; Lu, Ngan Thi; Cicuzza, Daniele; Knapp, Ralf; Luong, Thien Tam; Nitta, Joel H; Gao, Xin-Fen; Zhang, Li-Bing

    2017-09-01

    The Old World fern genus Pyrrosia (Polypodiaceae) offers a rare system in ferns to study morphological evolution because almost all species of this genus are well studied for their morphology, anatomy, and spore features, and various hypotheses have been proposed in terms of the phylogeny and evolution in this genus. However, the molecular phylogeny of the genus lags behind. The monophyly of the genus has been uncertain and a modern phylogenetic study of the genus based on molecular data has been lacking. In the present study, DNA sequences of five plastid markers of 220 accessions of Polypodiaceae representing two species of Drymoglossum, 14 species of Platycerium, 50 species of Pyrrosia, and the only species of Saxiglossum (subfamily Platycerioideae), and 12 species of other Polypodiaceae representing the remaining four subfamilies are used to infer a phylogeny of the genus. Major results and conclusions of this study include: (1) Pyrrosia as currently circumscribed is paraphyletic in relation to Platycerium and can be divided into two genera: Pyrrosia s.s. and Hovenkampia (gen. nov.), with Hovenkampia and Platycerium forming a strongly supported clade sister to Pyrrosia s.s.; (2) Subfamily Platycerioideae should contain three genera only, Hovenkampia, Platycerium, and Pyrrosia s.s.; (3) Based on the molecular phylogeny, macromorphology, anatomical features, and spore morphology, four major clades in the genus are identified and three of the four are further resolved into four, four, and six subclades, respectively; (4) Three species, P. angustissima, P. foveolata, and P. mannii, not assigned to any groups by Hovenkamp (1986) because of their unusual morphology, each form monospecific clades; (5) Drymoglossum is not monophyletic and those species previously assigned to this genus are resolved in two different subclades; (6) Saxiglossum is resolved as the first lineage in the Niphopsis clade; and (7) The evolution of ten major morphological characters in the

  10. Capacity of the aquatic fern (Salvinia minima Baker) to accumulate high concentrations of nickel in its tissues, and its effect on plant physiological processes

    Energy Technology Data Exchange (ETDEWEB)

    Fuentes, Ignacio I.; Espadas-Gil, Francisco; Talavera-May, Carlos; Fuentes, Gabriela; Santamaría, Jorge M., E-mail: jorgesm@cicy.mx

    2014-10-15

    Highlights: • We document the capacity of an aquatic fern to hyper-accumulate Ni. • Effects of high Ni concentrations uptake on plant performance is documented. • High concentration of Ni in tissues damage photosynthesis. • Damage is related to carboxylation mechanisms than to electron transfer efficiency. • S. minima is a good candidate for remediation of water bodies contaminated with Ni. - Abstract: An experiment was designed to assess the capacity of Salvinia minima Baker to uptake and accumulate nickel in its tissues and to evaluate whether or not this uptake can affect its physiology. Our results suggest that S. minima plants are able to take up high amounts of nickel in its tissues, particularly in roots. In fact, our results support the idea that S. minima might be considered a hyper-accumulator of nickel, as it is able to accumulate 16.3 mg g{sup −1} (whole plant DW basis). Our results also showed a two-steps uptake pattern of nickel, with a fast uptake of nickel at the first 6 to 12 h of being expose to the metal, followed by a slow take up phase until the end of the experiment at 144 h. S. minima thus, may be considered as a fern useful in the phytoremediation of residual water bodies contaminated with this metal. Also from our results, S. minima can tolerate fair concentrations of the metal; however, at concentrations higher than 80 μM Ni (1.5 mg g{sup −1} internal nickel concentration), its physiological performance can be affected. For instance, the integrity of cell membranes was affected as the metal concentration and exposure time increased. The accumulation of high concentrations of internal nickel did also affect photosynthesis, the efficiency of PSII, and the concentration of photosynthetic pigments, although at a lower extent.

  11. Growth dynamics of fine roots in a coniferous fern forest site close to Forsmark in the central part of Sweden

    Energy Technology Data Exchange (ETDEWEB)

    Persson, Hans; Stadenberg, Ingela (SLU, Dept. of Ecology and Environmental Research, Uppsala (Sweden))

    2007-12-15

    The seasonal growth dynamics of live and dead roots for trees and the field layer species (g/m2, varying diameter fractions) and live/dead ratios were analysed at a fresh/moist coniferous fern forest site close to the nuclear power plant at Forsmark in the central eastern parts of Sweden. The changes in depth distribution of fine roots were observed at depth intervals of the top humus horizon down to 40 cm in the mineral soil profile. The bulk of living fine roots of trees (< 1 mm in diameter) were found in the mineral soil horizon the total profile down to 40 cm of the mineral soil, where 89, 82, 83 and 89% of the total amount in the whole profile were found. The upper 2.5 cm part of the humus layer contained 83, 81, 100 and 100% of all roots of the humus layer on the four different sampling occasions. High amounts of living fine roots were found in the upper 10 cm of the mineral soil horizon viz. 84, 76, 91 and 69% of the total mineral soil layer. Consequently, both the top soil horizons of the humus and the mineral soil layers were heavily penetrated by living fine roots. The highest proportion of living fine roots was found in the top 2.5 cm of the humus layer. Accordingly, the live/dead ratio of fine roots (< 1 mm in diameter) decreased from the top of the humus layer to the lower part of mineral soil horizon from 8.0-0.3, 0.8-0.2, 4.4-0.4 and 3.3-0.7 (g g-1) for the four sampling occasions, respectively. We concluded that the decrease in the live/ dead ratio was related to decreased vitality with depth of the fine roots in the soil profile. The highest live/dead ratio was found in the upper 2.5 cm of the humus layer for both the tree and field-layer species. This distribution pattern was most evident for tree fine roots < 1 mm in diameter. The mean fine-root biomass (live tissue < 1 mm in diameter) of tree species for the total profile varied on the four sampling occasions between 317, 113, 139 and 248 g m-2. The related fine root necromass (dead tissue

  12. El ciudadano trabajador en la transición del México colonial al independiente: la obra de José Joaquín Fernández de Lizardi

    OpenAIRE

    Insúa, M. (Mariela)

    2012-01-01

    Este artículo analiza la representación de la figura del ciudadano trabajador en la obra literaria y periodística de José Joaquín Fernández de Lizardi (1776-1810) en relación con el contexto histórico y social del México de finales de la colonia y comienzos de la vida independiente.

  13. Un escritor ante las instituciones: el caso de Nicolás Fernández de Moratín (1737-1780

    Directory of Open Access Journals (Sweden)

    Philip DEACON

    2009-11-01

    Full Text Available RESUMEN: En la España dieciochesca, cuando el mercado editorial no se había desarrollado lo suficiente para que un hombre de letras viviera sólo de su pluma, el escritor tenía que aprender a navegar por el complejo mundo institucional. El peso de entidades como la monarquía, la nobleza y la Iglesia seguía siendo grande, pero el espíritu renovador de la época dio lugar a nuevos organismos como las academias, sociedades económicas, e incluso instituciones menos definidas como la prensa y la tertulia cultural. Este artículo traza la carrera de Nicolás Fernández de Moratín, describiendo cómo se enfrentó con esas entidades y precisando cómo influyeron en sus escritos. Algunas instituciones como las educativas, profesionales o eclesiásticas conformaron las actividades del escritor tanto en el terreno ideológico como en el estilístico; otras, como en el caso de Moratín la Sociedad Económica Matritense, abren nuevas perspectivas para dar resultados literarios singulares al producirse una confluencia entre formas tradicionales y temas nuevos.ABSTRACT: In eighteenth-century Spain, where the literary world was insufficiently developed to allow authors to live by the pen, writers had to learn to negotiate the complex ways of established institutions. The prevailing influence of the monarchy, nobility and Church was great, but the spirit of renewal evident during the period gave rise to new organizations such as the royal academies, economic societies and less clearly identifiable institutions such as the press or the cultural club. The present article outlines the career of Nicolás Fernández de Moratín, demonstrating how the author negotiated these organizations and how they influenced his writings. Some institutions, like those belonging to the educational, professional and ecclesiastical worlds, influenced the writer both in an ideological and stylistic sense; others, as in Moratín’s case the Madrid Economic Society, provided an

  14. Study on transportation and accumulation mechanism of cadmium in metal-hyperaccumulating fern, Athyrium yokoscense, by synchrotron radiation x-ray fluorescence analysis

    International Nuclear Information System (INIS)

    Taoka, Hiroki; Nakai, Izumi; Hokura, Akiko; Goto, Fumiyuki; Yoshihara, Toshihiro; Abe, Tomoko; Terada, Yasuko

    2012-01-01

    High energy synchrotron radiation micro X-ray fluorescence (HE-SR-μ-XRF) analysis and X-ray absorption fine structure (XAFS) analysis were applied to reveal accumulation mechanism of Cd in a generated callus of Cd hyperaccumulator fern Athyrium yokoscense. The effects of plant age on the distributions and the chemical forms of Cd were examined using the plant grown in the 1/2 M Murashige and Skoog (MS) medium containing 200 μM Cd. The callus grew vigorously with periodical medium change. The μ-XRF imaging of the mature and young root showed that Cd was located around the cell wall of the epidermis, cortex, endodermis and vascular bundles. It is estimated that Cd absorbed from the root was transported to the shoots via the apoplast. On the other hand, Cd was accumulated in the cell wall of the epidermis, cortex and vascular bundles in the stem. Furthermore, the concentration of Cd in the vascular bundles of the mature stem was higher than that of the young stem. On the other hand, Cd located in whole area in the leaf. The Cd K-edge XAFS analysis revealed that the majority of Cd in the roots of both mature and immature stages of A. yokoscense is bounded to the oxygen ligands. In contrast, it is found that Cd was bound to sulfur ligands as well as to oxygen ligands in the shoots. (author)

  15. “The Journey” as an Expression of Mysticism in Sergio Fernández’s Segundo Sueño

    Directory of Open Access Journals (Sweden)

    Claudia Ramos Aguilar

    2015-02-01

    Full Text Available In this article the relationship which can be established between the dreamsof Anabasis in sor Juana Inés de la Cruz’s poem, Primero sueño and the novelby Sergio Fernández, Segundo sueño, is analized in a concordance where the soul during its journey through the supra lunar spheres, or in the transmutation of natural elements —rain, snow and mud—, experiences the mystery of itsencounter with the divine as a process of initiation.In the poem, the pursuit of higher knowledge is a trap; in the novel, the crossroads is found in the transgressive eroticism. These two trips of anabasis,the first and the second dream, translate the wink announcing the succession ina fall. In both cases, the excess of the soul, a tragic hero mask, melts the wingsof Icarus and conduces to the death of Phaeton, the death of the inexperienced charioteer of the divine chariot.

  16. «Novela sin mundo» y otras técnicas para el desvanecimiento del yo en Macedonio Fernández

    Directory of Open Access Journals (Sweden)

    Selnich Vivas Hurtado

    2017-01-01

    Full Text Available A través de Museo de la novela de la Eterna y los conceptos de «Belarte» y «Humorismo», Macedonio Fernández se propone ha - cer una novela experimental en donde sea posible la duda y el des - vanecimiento del yo. La masificación y la industrialización de la Buenos Aires de finales del siglo XiX y principios del XX trajeron como consecuencia la fragmentación y enajenación del sujeto. Por lo tanto, el arte y específicamente la literatura, por medio de las vanguardias, se dieron a la tarea de encontrar formas de nombrar ese entorno transformado. En este contexto, Macedonio comienza a planificar su novela, una novela que no comienza y que teoriza sobre su misma construcción, una novela para liberar al sujeto. De acuerdo con lo anterior, este artículo se propone analizar cómo en dicha novela se lleva a cabo el desvanecimiento del yo a la luz de la Belarte y el Humorismo, y cómo Macedonio deja para la literatura una novela «fallida».

  17. Promotion of arsenic phytoextraction efficiency in the fern Pteris vittata by the inoculation of As-resistant bacteria: a soil bioremediation perspective.

    Science.gov (United States)

    Lampis, Silvia; Santi, Chiara; Ciurli, Adriana; Andreolli, Marco; Vallini, Giovanni

    2015-01-01

    A greenhouse pot experiment was carried out to evaluate the efficiency of arsenic phytoextraction by the fern Pteris vittata growing in arsenic-contaminated soil, with or without the addition of selected rhizobacteria isolated from the polluted site. The bacterial strains were selected for arsenic resistance, the ability to reduce arsenate to arsenite, and the ability to promote plant growth. P. vittata plants were cultivated for 4 months in a contaminated substrate consisting of arsenopyrite cinders and mature compost. Four different experimental conditions were tested: (i) non-inoculated plants; (ii) plants inoculated with the siderophore-producing and arsenate-reducing bacteria Pseudomonas sp. P1III2 and Delftia sp. P2III5 (A); (iii) plants inoculated with the siderophore and indoleacetic acid-producing bacteria Bacillus sp. MPV12, Variovorax sp. P4III4, and Pseudoxanthomonas sp. P4V6 (B), and (iv) plants inoculated with all five bacterial strains (AB). The presence of growth-promoting rhizobacteria increased plant biomass by up to 45% and increased As removal efficiency from 13% without bacteria to 35% in the presence of the mixed inoculum. Molecular analysis confirmed the persistence of the introduced bacterial strains in the soil and resulted in a significant impact on the structure of the bacterial community.

  18. Promotion of arsenic phytoextraction efficiency in the fern Pteris vittata by the inoculation of As-resistant bacteria: a soil bioremediation perspective

    Science.gov (United States)

    Lampis, Silvia; Santi, Chiara; Ciurli, Adriana; Andreolli, Marco; Vallini, Giovanni

    2015-01-01

    A greenhouse pot experiment was carried out to evaluate the efficiency of arsenic phytoextraction by the fern Pteris vittata growing in arsenic-contaminated soil, with or without the addition of selected rhizobacteria isolated from the polluted site. The bacterial strains were selected for arsenic resistance, the ability to reduce arsenate to arsenite, and the ability to promote plant growth. P. vittata plants were cultivated for 4 months in a contaminated substrate consisting of arsenopyrite cinders and mature compost. Four different experimental conditions were tested: (i) non-inoculated plants; (ii) plants inoculated with the siderophore-producing and arsenate-reducing bacteria Pseudomonas sp. P1III2 and Delftia sp. P2III5 (A); (iii) plants inoculated with the siderophore and indoleacetic acid-producing bacteria Bacillus sp. MPV12, Variovorax sp. P4III4, and Pseudoxanthomonas sp. P4V6 (B), and (iv) plants inoculated with all five bacterial strains (AB). The presence of growth-promoting rhizobacteria increased plant biomass by up to 45% and increased As removal efficiency from 13% without bacteria to 35% in the presence of the mixed inoculum. Molecular analysis confirmed the persistence of the introduced bacterial strains in the soil and resulted in a significant impact on the structure of the bacterial community. PMID:25741356

  19. Promotion of arsenic phytoextraction efficiency in the fern Pteris vittata by the inoculation of As-resistant bacteria: a soil bioremediation perspective.

    Directory of Open Access Journals (Sweden)

    Silvia eLampis

    2015-02-01

    Full Text Available A greenhouse pot experiment was carried out to evaluate the efficiency of arsenic phytoextraction by the fern Pteris vittata growing in arsenic-contaminated soil, with or without the addition of selected rhizobacteria isolated from the polluted site. The bacterial strains were selected for arsenic resistance, the ability to reduce arsenate to arsenite, and the ability to promote plant growth. P. vittata plants were cultivated for 4 months in a contaminated substrate consisting of arsenopyrite cinders and mature compost. Four different experimental conditions were tested: i non-inoculated plants; ii plants inoculated with the siderophore-producing and arsenate-reducing bacteria Pseudomonas sp. P1III2 and Delftia sp. P2III5 (A; iii plants inoculated with the siderophore and indoleacetic acid-producing bacteria Bacillus sp. MPV12, Variovorax sp. P4III4 and Pseudoxanthomonas sp. P4V6 (B, and iv plants inoculated with all five bacterial strains (AB. The presence of growth-promoting rhizobacteria increased plant biomass by up to 45% and increased As removal efficiency from 13% without bacteria to 35% in the presence of the mixed inoculum. Molecular analysis confirmed the persistence of the introduced bacterial strains in the soil and resulted in a significant impact on the structure of the bacterial community.

  20. RICHNESS AND FLORISTIC COMPOSITION OF THE FERN COMMUNITY IN RIPARIAN FOREST OF THE RIVER ‘CADEIA’, IN RIO GRANDE DO SUL STATE, BRAZIL

    Directory of Open Access Journals (Sweden)

    Ivanete Teresinha Mallmann

    2014-03-01

    Full Text Available http://dx.doi.org/10.5902/1980509813327The present study analyzed richness and specific composition of the fern community in fragments fromthe riparian forest of river ‘Cadeia’, under different levels of human impact, in Santa Maria do Herval, RioGrande do Sul state, Brazil. An amount of 120 sample units were delimited, equitably distributed in threefragments (FI, II and III in which all species were surveyed and the richness was recorded. The floristiccomposition among fragments was compared using Jaccard’s index and spatial distribution of units wasevaluated through multidimensional scaling. Richness data were presented in the form of rarefaction curvesbased on samples and non-parametric diversity estimators. A total of 40 species were found, belonging to13 families. The greater floristic similarity was between FI and FII. Sample units from FI formed the mostdefined grouping and they had more exclusive species than the others. The rarefaction curve for the totalsampling almost reached the asymptote and estimators indicated a maximum of 45 species, which meansthat the majority of species was surveyed at the study site. A decreasing gradient of mean richness per unitwas observed as the urbanization increased in the matrix habitat of the fragments. These results form a database to be used in management, conservation and reforestation measures in degraded riparian forests. Theycan be directly compared to results from other studies that used rarefaction and richness estimators, whichis not possible to do with many of the surveys accomplished in Brazil so far.

  1. The Middle Triassic megafossil flora of the Basin Creek Formation, Nymboida Coal Measures, New South Wales, Australia. Part 3. Fern-like foliage

    Energy Technology Data Exchange (ETDEWEB)

    Holmes, W.B.K. [Noonee Nyrang, Wellington, NSW (Australia)

    2003-01-31

    Two quarries in the Basin Creek Formation of the Middle Triassic Nymboida Coal Measures have yielded numerous examples of fern-like foliage. No affiliated fertile material is available to place the fronds in a natural classification. Twenty three species in twelve genera are described as morpho-taxa in Order and Family Incertae Sedis. Plants described in this paper are: Cladophlebis conferta sp. nov., C octonerva sp. nov., C. paucinerva sp. nov., C. relallachfisp. nov., C. sinuala sp. nov., C. lenuoinnula sp. nov., Diconymba sparnosa gen. et sp. nov., Gouldianum alelhopleroides gen. et sp. nov., Leconama stachyophylla gen. et sp. nov., Micronymbopteris repens gen. et sp. nov., Nymbiella lacerata gen. et sp. nov., Nymboidiantum glossophyllum (Tenison-Woods) gen. et comb. nov., N. multilobatum gen. et sp. nov., N. elegans gen. et sp. nov., N. fractiflexum gen. et sp. nov., N. robustum gen. et sp. nov., Nymbophlebis polymorpha gen. et sp. nov., Nymbopteron dejerseyi (Retallack) gen. et comb. nov.,N. foleyi gen. et sp. nov., N. uncinatum gen. et sp. nov., Nymborhipteris radiata gen. et sp. nov., Ptilotonymba curvinervia gen. et sp. nov. and Sphenopteris speciosa sp. nov. The diversity of this new material demonstrates the remarkable recovery of Gondwana vegetation following the end-Permian extinction event.

  2. Heterogeneous photo-Fenton treatment for the reduction of pharmaceutical contamination in Madrid rivers and ecotoxicological evaluation by a miniaturized fern spores bioassay.

    Science.gov (United States)

    Rodríguez-Gil, José L; Catalá, Myriam; Alonso, Silvia González; Maroto, Raúl Romo; Valcárcel, Yolanda; Segura, Yolanda; Molina, Raúl; Melero, Juan A; Martínez, Fernando

    2010-06-01

    Fifty-six pharmaceuticals of various chemical groups, such as anti-inflammatory, antibacterial and cardiovascular drugs, were detected in four selected river waters receiving sewage effluents in the Community of Madrid (Spain). A promising approach for the degradation of those residues is the application of a photo-Fenton treatment. Several new bioassays using fern spores were employed for the evaluation of acute and chronic toxicity based on mitochondrial activity, DNA and chlorophyll quantifications of as-received river water and photo-Fenton-treated samples. photo-Fenton treatment provided a high degree of total organic carbon mineralization with up to 70% reduction for river water samples. In addition, the elimination of most of the studied pharmaceutical compounds was confirmed. A few compounds, however (salicylic acid, ofloxacin, caffeine, cotinine and nicotine), seemed more resistant, with after-treatment concentrations between 4 and 44ngL(-1). Nicotine showed the most refractory behaviour with concentrations ranging from 29 to 224ngL(-1) for treated samples. Photo-Fenton treatment yielded a significant decrease in acute and chronic toxicity, even though some residual toxicity remained after treatment. This fact seemed to be related to the presence of toxicants in the water matrix, probably of inorganic nature, rather than the toxic effect of the studied pharmaceutical compounds, as revealed by the effective removal of these compounds and high TOC mineralization of photo-Fenton treatments.

  3. Study on accumulation mechanism of lead and copper in metal-hypertolerant fern, Athyrium yokoscense, by micro-XRF analysis utilizing synchrotron radiation

    International Nuclear Information System (INIS)

    Mitsuo, Sakiko; Kashiwabara, Teruhiko; Hokura, Akiko; Nakai, Izumi; Kitajima, Nobuyuki; Goto, Fumiyuki; Yoshihara, Toshihiro; Abe, Tomoko

    2009-01-01

    Athyrium yokoscense is a plant which accumulates high level of heavy metals such as Cu, Zn, Pb and Cd, and is expected to be used for phytoremediation. This paper reports the distribution and the chemical forms of Pb and Cu in underground parts (root and old leaf stalks) of the metal-hypertolerant fern, A. yokoscense, by synchrotron radiation micro-XRF imaging and micro-XANES analyses. The old and new tissues of root and leaf stalks were prepared for micro-XRF analysis. The XRF imaging of the young root revealed that K, Cu and Zn were distributed in whole area of cross-section, whereas Pb was found in a certain part of the epidermal tissue. For the old root, Pb and Cu were mainly distributed in the cell wall of the whole tissue. The distribution of heavy metal in old tissue is different from those of new tissue, and consequently it was assumed that the root at different age have different heavy metal accumulation mechanism. Alternatively, for the old leaf stalks, Cu and Pb were highly accumulated in a specific part located around the vascular tissue. Cu K-edge micro-XANES analysis indicated that the chemical form of Cu at the Cu accumulating point was Cu (II). (author)

  4. Histopathological aspects of Bovine Enzootic Hematuria in Brazil Aspectos histopatológicos da Hematúria Enzoótica Bovina no Brasil

    Directory of Open Access Journals (Sweden)

    Paulo Vargas Peixoto

    2003-06-01

    Full Text Available The bladder lesions of 59 cattle, from the States of Rio de Janeiro, São Paulo, Minas Gerais, Espírito Santo, Rio Grande do Sul, Santa Catarina, Paraná and Amazon, affected by Bovine Enzootic Haematuria (BEH, were studied histologically. The objective of this study was to describe and reclassify neoplastic and non-neoplastic alterations not yet reported, according to the more complete current nomenclature used in human medicine. There was an almost complete identity with alterations observed in the bladder of man. Due to the occurrence of two or more neoplasms in the same animal, differences in the methodology and in the concept of classification, a more precise comparison was not possible. Coexistence of different types of epithelial and/or mesenchymal tumour growth was frequently seen. Rare neoplasms or differentiations not previously described were found in the bladder of some animals affected by BEH. These were trabecular carcinoma with Paneth cells differentiation, mesonephroid adenoma, mesonephroid adenocarcinoma, "signet ring" cell carcinoma, plasmocytoid carcinoma, chromophobe cell carcinoma and nested type of transitional cell carcinoma. Haemangiosarcomas originating from haemangiomas were also observed. This study also revealed the occurrence of many tumors with anaplasia and pronounced infiltrative features, but which did not metastasize. The elucidation of the cause of this "barrier against metastases" and its relationship with chemical carcinogenesis induced by the ptaquiloside, the active principle of bracken fern (Pteridium aquilinum, could be of interest to future research on the control ofneoplasia in man and animals.Com o objetivo de descrever alterações neoplásicas e não-neoplásicas ainda não relatadas e, paralelamente, reclassificá-las de acordo com nomenclatura mais completa e atual utilizada em medicina humana, foram estudadas, histologicamente, lesões da bexiga de 59 bovinos com Hematúria Enzoótica (HEB

  5. Modelación de la conectividad de las subpoblaciones de la langosta de Juan Fernández (Jasus frontalis, a través de un modelo biofísico Modeling the connectivity of Juan Fernández rock lobster (Jasus frontalis, subpopulations through a biophysical model

    Directory of Open Access Journals (Sweden)

    Javier Porobic

    2012-09-01

    Full Text Available El archipiélago de Juan Fernández y el de las islas Desventuradas, corresponden a dos pequenos grupos de islas oceánicas, separadas entre sí 460 mn y ubicadas aproximadamente a 360 mn frente a la costa chilena. La economía local de estas islas se basa casi exclusivamente en la extracción y comercialización de recursos marinos, focalizados principalmente en la explotación de la langosta (Jasusfrontalis. Esta especie endémica se encuentra distribuída en ambos archipiélagos conformando una metapoblación, donde su dinámica y estructura poblacional sería modulada por forzantes oceanográficos, especialmente durante su prolongada fase larval planctónica. Se evaluó la estructura poblacional y el grado de conectividad-retención dentro y entre las diferentes islas mediante el uso de modelos biofísicos acoplados (modelos hidrodinámicos provenientes del modelo OFES y un modelo individuo basado de J. frontalis. El análisis de los resultados del modelo hidrodinámico indica la presencia de estructuras de mesoescala asociadas al sistema de islas. Índices provenientes del modelo biofísico muestran niveles importantes de conectividad-retención dentro y entre los sistemas de islas y una fuerte variación interanual de estos. Los resultados de la modelación biofísica indican que la varibilidad en el reclutamiento asociado al archipiélago de Juan Fernández depende mayoritariamente de larvas originadas en este mismo sistema, con un aporte importante de reclutas hacia el archipiélago de las Desventuradas. Se realizaron estudios de sensibilidad del modelo biofísico para identificar forzantes potenciales de las variables dependientes del modelo (e.g. índices de conectividad-retención, resultando en que los patrones temporales y espaciales reproductivos, la duración del estadio larval y la temporada (ano son altamente significativos. Finalmente, se propone que J. frontalis presenta una estructura metapoblacional con un alto nivel de

  6. Population genetic structure and phylogeographical pattern of a relict tree fern, Alsophila spinulosa (Cyatheaceae), inferred from cpDNA atpB- rbcL intergenic spacers.

    Science.gov (United States)

    Su, Yingjuan; Wang, Ting; Zheng, Bo; Jiang, Yu; Chen, Guopei; Gu, Hongya

    2004-11-01

    Sequences of chloroplast DNA (cpDNA) atpB- rbcL intergenic spacers of individuals of a tree fern species, Alsophila spinulosa, collected from ten relict populations distributed in the Hainan and Guangdong provinces, and the Guangxi Zhuang region in southern China, were determined. Sequence length varied from 724 bp to 731 bp, showing length polymorphism, and base composition was with high A+T content between 63.17% and 63.95%. Sequences were neutral in terms of evolution (Tajima's criterion D=-1.01899, P>0.10 and Fu and Li's test D*=-1.39008, P>0.10; F*=-1.49775, P>0.10). A total of 19 haplotypes were identified based on nucleotide variation. High levels of haplotype diversity (h=0.744) and nucleotide diversity (Dij=0.01130) were detected in A. spinulosa, probably associated with its long evolutionary history, which has allowed the accumulation of genetic variation within lineages. Both the minimum spanning network and neighbor-joining trees generated for haplotypes demonstrated that current populations of A. spinulosa existing in Hainan, Guangdong, and Guangxi were subdivided into two geographical groups. An analysis of molecular variance indicated that most of the genetic variation (93.49%, P<0.001) was partitioned among regions. Wright's isolation by distance model was not supported across extant populations. Reduced gene flow by the Qiongzhou Strait and inbreeding may result in the geographical subdivision between the Hainan and Guangdong + Guangxi populations (FST=0.95, Nm=0.03). Within each region, the star-like pattern of phylogeography of haplotypes implied a population expansion process during evolutionary history. Gene genealogies together with coalescent theory provided significant information for uncovering phylogeography of A. spinulosa.

  7. Compression-cuticle relationship of seed ferns: Insights from liquid-solid states FTIR (Late Palaeozoic-Early Mesozoic, Canada-Spain-Argentina)

    Science.gov (United States)

    Zodrow, E.L.; D'Angelo, J. A.; Mastalerz, Maria; Keefe, D.

    2009-01-01

    Cuticles have been macerated from suitably preserved compressed fossil foliage by Schulze's process for the past 150 years, whereas the physical-biochemical relationship between the "coalified layer" with preserved cuticle as a unit has hardly been investigated, although they provide complementary information. This relationship is conceptualized by an analogue model of the anatomy of an extant leaf: "vitrinite (mesophyll) + cuticle (biomacropolymer) = compression". Alkaline solutions from Schulze's process as a proxy for the vitrinite, are studied by means of liquid-solid states Fourier transform infrared spectroscopy (FTIR). In addition, cuticle-free coalified layers and fossilized cuticles of seed ferns mainly from Canada, Spain and Argentina of Late Pennsylvanian-Late Triassic age are included in the study sample. Infrared data of cuticle and alkaline solutions differ which is primarily contingent on the mesophyll +biomacropolymer characteristics. The compression records two pathways of organic matter transformation. One is the vitrinized component that reflects the diagenetic-post-diagenetic coalification history parallel with the evolution of the associated coal seam. The other is the cuticle that reflects the sum-total of evolutionary pathway of the biomacropolymer, its monomeric, or polymeric fragmentation, though factors promoting preservation include entombing clay minerals and lower pH conditions. Caution is advised when interpreting liquid-state-based FTIR data, as some IR signals may have resulted from the interaction of Schulze's process with the cuticular biochemistry. A biochemical-study course for taphonomy is suggested, as fossilized cuticles, cuticle-free coalified layers, and compressions are responses to shared physicogeochemical factors. ?? 2009 Elsevier B.V. All rights reserved.

  8. Diversity of Endophytic Bacteria in a Fern Species Dryopteris uniformis (Makino) Makino and Evaluation of Their Antibacterial Potential Against Five Foodborne Pathogenic Bacteria.

    Science.gov (United States)

    Das, Gitishree; Park, Seonjoo; Baek, Kwang-Hyun

    2017-05-01

    The fern plant Dryopteris uniformis has traditionally been used in herbal medicine and possesses many biological activities. This study was conducted to explore the endophytic bacterial diversity associated with D. uniformis and evaluate their antibacterial potential against foodborne pathogenic bacteria (FPB). Among 51 isolated endophytic bacteria (EB), 26 EB were selected based on their morphological characteristics and identified by 16S rRNA gene analysis. The distribution of EB was diverse in the leaf and the stem/root tissues. When the EB were screened for antibacterial activity against five FPB, Listeria monocytogenes, Salmonella Typhimurium, Bacillus cereus, Staphylococcus aureus, and Escherichia coli O157:H7, four EB Bacillus sp. cryopeg, Paenibacillus sp. rif200865, Staphylococcus warneri, and Bacillus psychrodurans had a broad spectrum of antibacterial activity (9.58 ± 0.66 to 21.47 ± 0.27 mm inhibition zone). The butanol solvent extract of B. sp. cryopeg and P. sp. rif200865 displayed effective antibacterial activity against the five FPB, which was evident from the scanning electron microscopy with irregular or burst cell morphology in the EB-treated bacteria compared to smooth and regular cells in case of the control bacteria. The minimum inhibitory concentration and minimum bactericidal concentration values ranged between 250-500 μg/mL and 500-100 μg/mL, respectively. The above outcomes signify the huge prospective of the selected EB in the food industry. Overall, the above results suggested that D. uniformis contains several culturable EB that possess effective antibacterial compounds, and that EB can be utilized as a source of natural antibacterial agents for their practical application in food industry to control the spread of FPB as a natural antibacterial agent.

  9. Using native epiphytic ferns to estimate the atmospheric mercury levels in a small-scale gold mining area of West Java, Indonesia.

    Science.gov (United States)

    Kono, Yuriko; Rahajoe, Joeni S; Hidayati, Nuril; Kodamatani, Hitoshi; Tomiyasu, Takashi

    2012-09-01

    Mercury pollution is caused by artisanal and small-scale gold mining (ASGM) operations along the Cikaniki River (West Java, Indonesia). The atmosphere is one of the primary media through which mercury can disperse. In this study, atmospheric mercury levels are estimated using the native epiphytic fern Asplenium nidus complex (A. nidus) as a biomonitor; these estimates shed light on the atmospheric dispersion of mercury released during mining. Samples were collected from 8 sites along the Cikaniki Basin during September-November, 2008 and September-November, 2009. The A. nidus fronds that were attached to tree trunks 1-3m above the ground were collected and measured for total mercury concentration using cold vapor atomic absorption spectrometry (CVAAS) after acid-digestion. The atmospheric mercury was collected using porous gold collectors, and the concentrations were determined using double-amalgam CVAAS. The highest atmospheric mercury concentration, 1.8 × 10(3) ± 1.6 × 10(3) ngm(-3), was observed at the mining hot spot, and the lowest concentration of mercury, 5.6 ± 2.0 ngm(-3), was observed at the remote site from the Cikaniki River in 2009. The mercury concentrations in A. nidus were higher at the mining village (5.4 × 10(3) ± 1.6 × 10(3) ngg(-1)) than at the remote site (70 ± 30 ngg(-1)). The distribution of mercury in A. nidus was similar to that in the atmosphere; a significant correlation was observed between the mercury concentrations in the air and in A. nidus (r=0.895, P<0.001, n=14). The mercury levels in the atmosphere can be estimated from the mercury concentration in A. nidus using a regression equation: log (Hg(A.nidu)/ngg(-1))=0.740 log (Hg(Air)/ngm (-3)) - 1.324. Copyright © 2012 Elsevier Ltd. All rights reserved.

  10. Compression-cuticle relationship of seed ferns: Insights from liquid-solid states FTIR (Late Palaeozoic-Early Mesozoic, Canada-Spain-Argentina)

    Energy Technology Data Exchange (ETDEWEB)

    Zodrow, Erwin L. [Palaeobotanical Laboratory, Cape Breton University, Sydney, Nova Scotia (Canada); D' Angelo, Jose A. [Instituto Argentino de Nivologia, Glaciologia y Ciencias Ambientales (IANIGLA), CCT-CONICET-Mendoza, Avda. Ruiz Leal s/n Parque Gral. San Martin (5500) Mendoza (Argentina); Area de Quimica, Instituto de Ciencias Basicas, Universidad Nacional de Cuyo, Centro Universitario - M5502JMA - Mendoza (Argentina); Mastalerz, Maria [Indiana Geological Survey, Indiana University, 611 North Walnut Grove, Bloomington, IN 47405-2208 (United States); Keefe, Dale [Molecular Spectroscopy Research Laboratory, Department of Chemistry, Cape Breton University, Sydney, Nova Scotia (Canada)

    2009-08-01

    Cuticles have been macerated from suitably preserved compressed fossil foliage by Schulze's process for the past 150 years, whereas the physical-biochemical relationship between the ''coalified layer'' with preserved cuticle as a unit has hardly been investigated, although they provide complementary information. This relationship is conceptualized by an analogue model of the anatomy of an extant leaf: ''vitrinite (mesophyll) + cuticle (biomacropolymer) = compression''. Alkaline solutions from Schulze's process as a proxy for the vitrinite, are studied by means of liquid-solid states Fourier transform infrared spectroscopy (FTIR). In addition, cuticle-free coalified layers and fossilized cuticles of seed ferns mainly from Canada, Spain and Argentina of Late Pennsylvanian-Late Triassic age are included in the study sample. Infrared data of cuticle and alkaline solutions differ which is primarily contingent on the mesophyll +biomacropolymer characteristics. The compression records two pathways of organic matter transformation. One is the vitrinized component that reflects the diagenetic-post-diagenetic coalification history parallel with the evolution of the associated coal seam. The other is the cuticle that reflects the sum-total of evolutionary pathway of the biomacropolymer, its monomeric, or polymeric fragmentation, though factors promoting preservation include entombing clay minerals and lower pH conditions. Caution is advised when interpreting liquid-state-based FTIR data, as some IR signals may have resulted from the interaction of Schulze's process with the cuticular biochemistry. A biochemical-study course for taphonomy is suggested, as fossilized cuticles, cuticle-free coalified layers, and compressions are responses to shared physicogeochemical factors. (author)

  11. Mitochondrial activity in fern spores of Cyathea costaricensis as an indicator of the impact of land use and water quality in rivers running through cloud forests.

    Science.gov (United States)

    Rodríguez-Romero, Alexis Joseph; Rico-Sánchez, Axel Eduardo; Catalá, Myriam; Sedeño-Díaz, Jacinto Elías; López-López, Eugenia

    2017-12-01

    Early-warning biomarkers, such as mitochondrial activity, have become a key tool in ecosystem assessment. This study aims to evaluate the response of mitochondrial activity in spores of the autochthonous fern Cyathea costaricensis as a bioassessment tool concurrently with land use and physicochemical evaluation in 11 sites along Bobos River, Veracruz, Mexico, to assess river water quality. Bobos River is located in the Nautla basin, northeastern Veracruz (Mexico); the upper river runs through a protected natural area (Filobobos River and adjacent areas). The study involved three monitoring periods: February, June and September 2014. In each study site, physicochemical water quality parameters were recorded to calculate the Water Quality Index (WQI); also, study sites were characterized in terms of land use. Water samples were collected to perform bioassays where spores of C. costaricensis were exposed to samples to assess mitochondrial activity; a positive control exposure test was run under controlled conditions to maximize mitochondrial activity. A Principal Component Analysis was performed to correlate land-use attributes with environmental variables and mitochondrial activity. Three river sections were identified: the upper portion was characterized by the dominance of native vegetation, the highest WQI (in September), and the lowest mitochondrial activity (63.87%-77.47%), related to the geological nature of the basin and high hardness levels. Mitochondrial activity peaked in September (98.32% ± 9.01), likely resulting from nutrient enrichment in the rainy season, and was lowest in February (74.54% ± 1.60) (p environmental characteristics such as land use and the geological nature of the basin, as well as with those related to human impacts. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Ciclo anual de la clorofila-α satelital en el archipiélago de Juan Fernández (33°S, Chile

    Directory of Open Access Journals (Sweden)

    Isabel Andrade

    2012-09-01

    Full Text Available La variabilidad espacial y temporal del ciclo anual de la clorofila-α en el archipiélago de Juan Fernández se analiza usando ocho anos de datos satelitales de clorofila-α, viento, corrientes y nivel del mar. Este archipiélago está conformado por tres islas: Robinson Crusoe-Santa Clara (RC-SC y Alejandro Selkirk (AS. Las islas RC-SC se encuentran en una región de alta energía cinética y mayores concentraciones de clorofila-α definida como Zona de Transición Costera, en cambio la isla AS se encuentra en una región de baja energía cinética y menores concentraciones de clorofila-α denominada Zona Oceánica. RC-SC posee un incremento de las concentraciones de clorofila-a en el lado suroeste, mientras que AS posee sus mayores concentraciones en el lado oeste, indicando la presencia de procesos forzantes diferentes. En ambas islas el ciclo anual de la clorofila es significativo y comienza a incrementar en abril, alcanzando valores relativamente altos entre junio y noviembre, disminuyendo hacia diciembre, hasta alcanzar un mínimo hacia fines de marzo. Este ciclo anual aparece desacoplado con el viento y acoplado con la energía cinética. Incrementos invernales de clorofila-a aparecen vinculados con remolinos de mesoescala provenientes de la zona continental, mientras que incrementos primaverales se podrían asociar a procesos locales vinculados al "efecto masa de isla". En ambas islas existen incrementos significativos de la clorofila-a en la banda anual y cuasi-bianual, pero sólo en AS se encontró una fluctuación significativa en la banda interanual vinculada con el Nino y la Oscilación del Sur.

  13. Regarding the Modern Virtue of Considering the Common good over one’s own Interests: Dreams and other Literary Devices in «Los paseos de la verdad» by Fernández de Lizardi

    Directory of Open Access Journals (Sweden)

    M.ª Isabel TERÁN ELIZONDO

    2011-01-01

    Full Text Available His article studies the presence of dreams as a recurring narrative element in the work of Fernández de Lizardi, and in particular in Los paseos de la verdad, published in five excerpts in 1815 in the Alacena de Frioleras, in imitation of the Sueños of torres Villarroel. Emphasis is placed on the moralizing intention of the author and the linking of dreams to the constitution of an ideal that of a new nation built upon a synthesis of the best ideas of the age, be they traditional or modern.

  14. Comportamiento de la gingivitis crónica en adolescentes de la Secundaria Básica “Jesús Fernández”. Santa Marta, Cárdenas

    OpenAIRE

    Zaldívar Bernal, Hilda Lídice; Cid Rodríguez, María del Carmen; Sánchez Gay, Juana María; Montes de Oca Ramos, Rebeca

    2014-01-01

    La gingivitis es la enfermedad periodontal más frecuente que afecta tanto a los adolescentes como a los pacientes adultos. Se realizó un estudio observacional descriptivo transversal con el objetivo de conocer la prevalencia de gingivitis en adolescentes entre 12 y 14 años de edad de la ESBU “Jesús Fernández Rodríguez”, del Consejo Popular Santa Marta, municipio Cárdenas, en el período comprendido de enero a julio de 2011. Los adolescentes fueron caracterizados según variables sociodemográfic...

  15. Asimetrías: Colección de Textos de Arquitectura. Número especial - homenaje a Margarita Fernández Gómez y Cecilio Sánchez-Robles Beltrán

    OpenAIRE

    Iborra Bernad, Federico Javier; Poyatos Sebastian, Javier

    2017-01-01

    Esta publicación se compone de una serie de textos, algunos de investigación y otros de recuerdo personal, escritos en memoria de la catedrática Margarita Fernández Gómez y del profesor Cecilio Sánchez-Robles Beltrán, ambos compañeros del Departamento de Composición Arquitectónica y fallecidos en el año 2015. En la primera parte del libro encontramos ocho textos que nos acercan a las semblanzas de los dos homenajeados, desde su faceta humana, docente e investigadora. A continuación se desarr...

  16. quality control

    International Nuclear Information System (INIS)

    Skujina, A.; Purina, S.; Riekstina, D.

    1999-01-01

    The optimal objects: soils, spruce needles and bracken ferns were found for the environmental monitoring in the regions of possible radioactive contamination - near SalaspiIs nuclear reactor and Ignalina nuclear power plant. The determination of Sr-90 was based on the radiochemical separation of Sr-90 (=Y-90) by HDEHP extraction and counting the Cerenkov radiation. The quality control of the results was carried out. (authors)

  17. Humboldt Bay Wetlands Review and Baylands Analysis. Volume II. Base Information.

    Science.gov (United States)

    1980-08-01

    consists primarily of thimbleberry, salmonberry, blackberry, creek dogwood, fireweed, bracken fern, skunk cabbage, nettle , lupine, salal, and willow...insect populations, and are, at the same time, very suscepti- ble to the toxic effects of insecticides concentrated in th- food chain. Marint Mammals...shrubs, and annuals which do exist are often protected from consumption by fences and insecticides . Insects and rodents are the common primary

  18. Madagascar sheds new light on the molecular systematics and biogeography of grammitid ferns: New unexpected lineages and numerous long-distance dispersal events.

    Science.gov (United States)

    Bauret, Lucie; Gaudeul, Myriam; Sundue, Michael A; Parris, Barbara S; Ranker, Tom A; Rakotondrainibe, France; Hennequin, Sabine; Ranaivo, Jaona; Selosse, Marc-André; Rouhan, Germinal

    2017-06-01

    Based on a worldwide phylogenetic framework filling the taxonomic gap of Madagascar and surrounding islands of the Western Indian Ocean (WIO), we revisited the systematics of grammitid fern species (Polypodiaceae). We also investigated the biogeographic origin of the extant diversity in Madagascar and estimated the relative influence of vicariance, long-distance dispersals (LDD) and in situ diversification. Phylogenetic inferences were based on five plastid DNA regions (atpB, rbcL, rps4-trnS, trnG-trnR, trnL-trnF) and the most comprehensive taxonomic sampling ever assembled (224 species belonging to 31 out of 33 recognized grammitids genera). 31 species from Madagascar were included representing 87% of the described diversity and 77% of the endemics. Our results confirmed a Paleotropical clade nested within an amphi-Atlantic grade. In addition, we identified three new major clades involving species currently belonging to Grammitis s.l., Ctenopterella and Enterosora. We resolved for the first time Grammitis s.s. as monophyletic, and Ctenopterella (newly tested here) and Enterosora as polyphyletic. The Neotropical genus Moranopteris was shown to also occur in Madagascar through a newly discovered species. Most importantly, we suggest a >30% inflation of the species number in the WIO due to the hidden diversity in >10 cryptic lineages, best explained by high morphological homoplasy. Molecular dating and ancestral areas reconstruction allowed identifying the Neotropics as the predominant source of LDD to the African-WIO region, with at least 12 colonization events within the last 20Ma. Repeated eastward migrations may be explained by transoceanic westerly winds transporting the dust-like spores. Tropical Asia s.l. would also have played a (minor) role through one dispersal event to Madagascar at the end of the Oligocene. Last, within the complex Malagasy region made of a mosaic of continental and oceanic islands located close to the African continent, we showed that

  19. Carlos Fernández Casado y José Acuña: los primeros puentes de altura estricta. Jaén, 1933-1935

    Directory of Open Access Journals (Sweden)

    Burgos, A.

    2012-12-01

    Full Text Available The bridge design catalogue “Puentes de altura Estricta” (Strict Height Bridges was one of the greatest creations of the brilliant spanish civil engineer Carlos Fernandez Casado. It was designed at the early 1930’s. It had a great relevance in the Spanish Civil Engineering of the 20th century. Nevertheless, its origins are little known. The first materializations of the “Collection” were six bridges that were constructed in the Jaén province, between 1933 and 1935. They were possible thanks to the determined support of other civil engineer, Jose Acuña y Gómez de la Torre. Later also he carried out the work himself. With this research its process of design and construction is reconstructed. Also bridges are described as they have come to the present day. With all this it is expected its great value as heritage elements be recognized.

    La “Colección de Puentes de Altura Estricta” fue una de las mayores creaciones del genial ingeniero de caminos español Carlos Fernández Casado. Fue diseñada a principios de los años 1930 y tuvo una gran trascendencia en la Ingeniería civil española del siglo XX. No obstante, sus orígenes son poco conocidos. Las primeras materializaciones de la “Colección” fueron seis puentes que se construyeron en la provincia de Jaén, entre 1933 y 1935. Fueron posibles gracias al decidido apoyo que prestó otro ingeniero de caminos, José Acuña y Gómez de la Torre. Posteriormente también se hizo cargo de su ejecución material. Con esta investigación se pretende reconstruir su proceso de diseño y construcción. También se describen los puentes tal como han llegado hasta nuestros días. Con todo ello se espera contribuir a que sea reconocido su gran valor como elementos patrimoniales.

  20. 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

    Directory of Open Access Journals (Sweden)

    Mervyn Manuel Hernández-Alvarado

    2016-07-01

    Full Text Available 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.

  1. Fernández de Oviedo (Historia General y Natural de las Indias, Libro VI, cap. LI y la etología clásica

    Directory of Open Access Journals (Sweden)

    Lens-Tuero, Jesús

    1997-06-01

    Full Text Available Not available.

    El presente trabajo se propone llamar la atención sobre un notable texto de Fernández de Oviedo (Historia General y Natural de las Indias, Libro VI, cap. LI que, en la medida que conocemos, no ha sido objeto de un comentario adecuado. En dicho texto se refiere el establecimiento de un pacto entre el hombre y el animal para asegurarse la supervivencia y mutuo beneficio, y la transformación de tal pacto en una relación de amistad y afecto. Tales relaciones pueden ser iluminadas desde la antropología clásica, en la que dichas categorías desempeñaron un papel no carente de relevancia.

  2. Juan Gálvez y Leandro Fernández de Moratín : cuatro escenas, obra de Gálvez, inspiradas en las comedias de Moratín

    Directory of Open Access Journals (Sweden)

    Juan Martínez Cuesta

    1999-01-01

    Full Text Available Este artículo analiza los cuatro lienzos ejecutados por Juan Gálvez (1774-1847 destinados a ilustrar la edición de las obras del dramaturgo Leandro Fernández de Moratín, publicadas por la Real Academia de la Historia, en 1830. Juan Gálvez fue uno de los pintores de cámara en la Corte de Fernando Vil, trabajando en distintos Reales Sitios. Fue director de la Real Academia de Bellas Artes de San Fernando. Los cuatro lienzos citados constituyeron el modelo para las litografías de las siguientes obras de Moratín: 1 «El sí de las niñas», acto III, escena XIII; 2 «La mojigata», acto II, escena II; 3 «La escuela de maridos», acto III, escena Vil; 4 «El médico a palos», acto ¡I, escena V.This article describes the four canvas painted by Juan Gálvez (1774-1847 in order to alústrate the comedies written by Leandro Fernández of Moratín, published by the Royal Spanish Academy of History, in 1830. Juan Gálvez was one of the official painter in Ferdinand Vlll's court, also he was director of the Royal Spanish Academy of Arts. The four canvas were models for litographies of Moratín's world's: 1 «El sí de las niñas», act III, scene XIII; 2 «La mojigata», act II, scene II; 3 «La escuela de maridos», act III, escena VII; 4 «El médico a palos», act II, scene V.

  3. Héroes y villanos del Nuevo Mundo en la Historia General y natural de las Indias de Gonzalo Fernández de Oviedo y Valdés

    Directory of Open Access Journals (Sweden)

    Coello de la Rosa, Alexandre

    2004-12-01

    Full Text Available Modern scholars analyze the chronicles of the Indies as a set of accounts, reports, ways of narrating the lived experiences in the New World, which were tinged with providentialism, mesianism and other value judgments from their rhetoric structure and judeo- Christian pastoral. The Historia by Fernández de Oviedo (1478-1557 is a perfect example. Although the Historia contains various elements of style that are representative of a genre whose main quality has undoubtedly to do with historiography, it incorporates many allegorical and imaginative levels belonging to a literary textual formation. In this article I shall explore both the construction of a model of Christian hero, and its reverse, as literary figures in the elaboration of a imperialistic and colonial historiography.

    Autores recientes insisten en que las crónicas de Indias son un conjunto de narraciones, relatos, estilos de contar las experiencias vividas en el Nuevo Mundo, impregnadas de providencialismo, mesianismo y de otros juicios de valor procedentes de su formación retórica y de la pastoral judeocristiana. La Historia de Fernández de Oviedo es un ejemplo perfecto. Aunque la Historia contiene ciertos rasgos de estilo propios de un género cuyo carácter tiene que ver indudablemente con la historiografía, incorpora múltiples planos alegóricos e imaginativos pertenecientes a una formación textual literaria. En este artículo vamos a analizar la construcción de un modelo de héroe cristiano, y su reverso, como figuras literarias en la elaboración de una historiografía colonial e imperialista.

  4. RESEÑA de: Álvarez Fernández, María y Beltrán Suárez, Soledad, Vivienda, gestión y mercado inmobiliarios en Oviedo en el tránsito de la Edad Media a la modernidad. El patrimonio urbano del cabildo catedralicio.

    Directory of Open Access Journals (Sweden)

    Roberto J. González Zalacaín

    2016-06-01

    Full Text Available Reseña de: Álvarez Fernández, María y Beltrán Suárez, Soledad, Vivienda, gestión y mercado inmobiliarios en Oviedo en el tránsito de la Edad Media a la modernidad. El patrimonio urbano del cabildo catedralicio. Bilbao. Servicio Editorial de la UPV/EHU, 2015. 220 págs. isbn: 978-84-9082-140-4.

  5. Propagação de pteridófitas in vitro e in vivo através de esporos Fern propagation in vitro and in vivo from spores

    Directory of Open Access Journals (Sweden)

    Flávia Próspero Borelli

    1990-01-01

    Full Text Available Sujeitas ao processo de extinção, em decorrência do extrativismo, as samambaias arbóreas Dicksonia sellowana (Presl. Hook e Cyathea schanschin Mart, das quais se obtémo xaxim, são espécies ainda pouco estudadas quanto à propagação. Com o objetivo de desenvolver um método adequado à propagação destas espécies, através de esporos, realizaram-se experimentos in vitro e in vivo. Para a desinfecção dos esporos, utilizaram-se soluções de hipoclorito de cálcio, em diferentes concentrações, ou de sódio, comparando-se sua eficiência. Para o cultivo in vitro, empregaram-se os meios nutritivos de Murashige e Skoog modificado e de Jones e a solução de Knop modificada. Na cultura in vivo utilizaram-se xaxim, estagno, terriço ou tijolo fragmentado. Como condições de cultivo, manteve-se a temperatura a 25 ±1°C e o fotoperíodo de 16 horas. Apesar da elevada contaminação durante o processo de germinação in vitro e in vivo, a desinfecção com hipoclorito de cálcio a 2% foi mais eficiente. Os esporos germinaram em 4 a 8 semanas e os prótalos formaram-se após 30 a 40 dias. Obteve-se maior percentagem de germinação e formação de prótalos com os meios de Jones e Knop, bem como xaxim e esfagno, e a germinação de esporos ocorreu mais rapidamente na ausência de esporângios.The objective of this experiment was to study the fern propagation from spores of Cyathea schanschin Mart and Dicksonia sellowiana (Presl. Hook. The spores were decontaminated in calcium or sodium hypochlorite solutions. The in vitro experiments were performed with the media: MS modified, Jones or Knop's solution modified. Tree-fern fibre, sphagnum moss, loam soil or brick peaces were, used for the in vivo experiments. The temperature was mantained at 25 ± 1°C and 16 hours of photoperiod for both treatments (In vivo and in vitro cultures. Besides the high percentage of contamination during the germination process, in vitro and in vivo, the best

  6. How biophysical interactions associated with sub- and mesoscale structures and migration behavior affect planktonic larvae of the spiny lobster in the Juan Fernández Ridge: A modeling approach

    Science.gov (United States)

    Medel, Carolina; Parada, Carolina; Morales, Carmen E.; Pizarro, Oscar; Ernst, Billy; Conejero, Carlos

    2018-03-01

    The Juan Fernández Ridge (JFR) is a chain of topographical elevations in the eastern South Pacific (∼33-35°S, 76-81.5°W). Rich in endemic marine species, this ridge is frequently affected by the arrival of mesoscale eddies originating in the coastal upwelling zone off central-southern Chile. The impacts of these interactions on the structure and dynamics of the JFR pelagic system have, however, not been addressed yet. The present model-based study is focused on the coupled influence of mesoscale-submesoscale processes and biological behavior (i.e., diel vertical migration) on the horizontal distribution of planktonic larvae of the spiny lobster (Jasus frontalis) around the JFR waters. Two case studies were selected from a hydrodynamic Regional Ocean Modeling System to characterize mesoscale and submesoscale structures and an Individual-based model (IBM) to simulate diel vertical migration (DVM) and its impact on the horizontal distribution and the patchiness level. DVM behavior of these larvae has not been clearly characterized, therefore, three types of vertical mechanisms were assessed on the IBM: (1) no migration (LG), (2) a short migration (0-50 m depth, DVM1), and (3) a long migration (10-200 m depth, DVM2). The influence of physical properties (eddy kinetic energy, stretching deformation and divergence) on larval aggregation within meso and submesoscale features was quantified. The patchiness index assessed for mesoscale and submesoscale structures showed higher values in the mesoscale than in the submesoscale. However, submesoscale structures revealed a higher accumulation of particles by unit of area. Both vertical migration mechanisms produced larger patchiness indices compared to the no migration experiment. DVM2 was the one that showed by far the largest aggregation of almost all the aggregation zones. Larval concentrations were highest in the submesoscale structures; these zones were characterized by low eddy kinetic energy, negative stretching

  7. Reprodutibilidade na classificação do teste de cristalização do filme lacrimal em pacientes com síndrome de Sjögren Reproducibility of the classification of ocular ferning patterns in Sjogren's syndrome patients

    Directory of Open Access Journals (Sweden)

    Sergio Felberg

    2008-04-01

    Full Text Available OBJETIVO: Verificar a reprodutibilidade da classificação dos padrões do teste de cristalização do filme lacrimal utilizando cinco examinadores diferentes e comparar os padrões de cristalização de pacientes portadores da síndrome de Sjögren com os de indivíduos não portadores de doenças da superfície ocular. MÉTODOS: Análise da cristalização da lágrima de 29 pacientes com Sjögren e 45 pacientes sem doenças da superfície ocular, através de microscópio com luz polarizada, utilizando a classificação de Rolando. Para fins estatísticos foi estudada a curva ROC (Receiver Operating Characteristic para determinar a melhor nota de corte do exame que separa indivíduos normais dos portadores da síndrome, índice de concordância Kappa (pPURPOSE: To verify the reproducibility of Rolando's classification of the tear ferning test using five different examiners and to compare the patterns of crystallization found in Sjögren's syndrome patients and normal subjects. METHODS: Tear ferning analysis of 29 patients with Sjögren's syndrome and of 45 patients without ocular disease were done using polarized light microscopy and the Rolando classification for tear ferning. Five examiners classified the ferning patterns of all the patients. ROC curve (Receiver Operating Characteristic was used to find out the best score for the correct syndrome diagnosis. Kappa index (p<0.0001 was used to compare the results of the examiners among them and check the test's reproducibility. Charts were drawn to compare the two groups' results. RESULTS: Throught the ROC curve the score of 2.50 for diagnosis of Sjögren's syndrome was stabilished. Considering the aggregated patterns I with II and III with IV, the examinors' level of pattern agreement was excellent (Kappa ranging from 0.82 to 0.97, p<0.0001. The group with Sjögren's syndrome was classified mostly as patterns III and IV and the patients without ocular disease mostly as I and II. CONCLUSION: The

  8. Ethos y legitimación política en los discursos de asunción de la presidente argentina Cristina Fernández de Kirchner

    Directory of Open Access Journals (Sweden)

    María Alejandra Vitale

    2013-01-01

    Full Text Available En el marco del análisis del discurso político que recupera la noción retórica de ethos y mediante el empleo de una metodología cualitativa, el artículo tiene el propósito de caracterizar las imágenes de sí que Cristina Fernández de Kirchner construyó en sus discursos de asunción como medio de legitimación de liderazgo político. Se trata de lo que hemos denominado ethos pedagógico-experto y, retomando análisis previos sobre el discurso presidencial de Néstor Kirchner, ethos militante. El primero responde a una escenografía profesoral donde la presidente argentina se posiciona como una profesora que da clase a sus alumnos, generada por el uso de procedimientos característicos del discurso explicativo. El ethos militante se corresponde con la violación de ciertas convenciones propias del género discurso de asunción y le permite identificarse con la figura y el gobierno de Néstor Kirchner. El ethos pedagógico-experto, por su parte, la ayuda a construir una identidad propia.

  9. Arsenic phytoextraction and hyperaccumulation by fern species Fitoextração e hiperacumulação de arsênio por espécies de samambaias

    Directory of Open Access Journals (Sweden)

    Maria Isidoria Silva Gonzaga

    2006-02-01

    Full Text Available Arsenic (As is an ubiquitous trace metalloid found in all environmental media. Its presence at elevated concentrations in soils derives from both anthropogenic and natural inputs. Arsenic is a toxic and carcinogenic element, which has caused severe environmental and health problem worldwide. Technologies currently available for the remediation of arsenic-contaminated sites are expensive, environmentally disruptive, and potentially hazardous to workers. Phytoextraction, a strategy of phytoremediation, uses plants to clean up contaminated soils and has been successfully applied to arsenic contaminated soils. It has the advantage of being cost-effective and environmentally friendly. A major step towards the development of phytoextraction of arsenic-impacted soils is the discovery of the arsenic hyper accumulation in ferns, first in Pteris vittata, which presented an extraordinary capacity to accumulate 2.3% arsenic in its biomass. Another fern, Pityrogramma calomelanos was found to exhibit the same hyperaccumulating characteristics. After that, screening experiments have revealed that the Pteris genus is really unique in that many species have the potential to be used in phytoextraction of arsenic. In general, these plants seem to have both constitutive and adaptive mechanisms for accumulating or tolerating high arsenic concentration. In the past few years, much work has been done to understand and improve the hyperaccumulating capability of these amazing plants. In particular, the field of molecular biology seems to hold the key for the future of the phytoremediation.O arsênio e um metalóide traço encontrado basicamente em todos os ambientes. Elevadas concentrações de arsênio no solo podem acontecer naturalmente devido ao intemperismo de rochas ricas em arsênio, como também de atividades antropogênicas. O arsênio é um elemento tóxico e cancerígeno. Em muitas partes do mundo, a contaminação pelo arsênio tem causado problemas

  10. Factores de riesgo que influyeron en el bajo peso al nacer en el policlínico "Aleida Fernández" Risk factors influencing low birth weight at "Aleida Fernandez" clinic

    Directory of Open Access Journals (Sweden)

    Eida Rosa Mariño Membribes

    2012-06-01

    Full Text Available Introducción: el nacimiento de un niño bajo peso ha constituido una incógnita para los profesionales de la salud en todos los tiempos. Objetivo: determinar los factores de riesgo que influyeron en el bajo peso al nacer, en el policlínico "Aleida Fernández"en los años 2007-2009. Métodos: se realizó un estudio retrospectivo descriptivo de corte transversal en los años 2007-2009. El universo lo constituyeron las 31 embarazadas cuyos bebés presentaron pesos por debajo de 2 500 g, y la muestra quedó formada por las 22 que recibieron atención prenatal en nuestra área de salud. Se utilizó porcentaje, media y desviación estándar como estadística descriptiva. Resultados: de los recién nacidos, 16 (72,7 % presentaron retardo del crecimiento intrauterino y 10 (45,4 % fueron pretérminos. El 100 % de las estudiadas, presentó sepsis vaginal y 18 (81,8 %, anemia. Conclusiones: el bajo peso al nacer continúa siendo un problema de salud y durante el embarazo existen numerosos factores de riesgos favorecedores y/o causales de este, tales como: el antecedente de abortos provocados y la nuliparidad, la desnutrición materna con insuficiente ganancia ponderal, la presencia de anemia y la sepsis vaginal. El trabajo continuo y sistemático, consciente y orientado hacia la población de mayor riesgo, constituye un elemento crucial, para la reducción de este evento negativo.Introduction: the birth of an underweight child has been a mystery to health professionals at all times. Objective: to determine risk factors influencing low birth weight, at "Aleida Fernández" clinic from 2007 to 2009. Methods: a retrospective cross sectional study was carried out from 2007 to 2009. The universe was 31 pregnant women whose babies had weights below 2 500 g, and the sample 22 pregnant women, who received prenatal care in our health area. We used percentage, mean and standard deviation as descriptive statistics. Results: 16 (72.7 % out of the newborns had

  11. Pespectivas y planteamientos de una poética: reflexiones sobre poesía y ficción en el comentario a la Divina Comedia de Fernández de Villegas

    Directory of Open Access Journals (Sweden)

    Cinthia M. Hamlin

    2012-01-01

    Full Text Available En 1515 se difunde en Burgos la primera traducción impresa de la Divina Comedia, edición que contaba con una exhaustiva glosa rodeando cada copla en la que Pedro Fernández de Villegas traducía y amplificaba, a su vez, el “Comento sopra la Comedia” de Landino (1481. En el siguiente trabajo analizaremos las reflexiones sobre poesía y ficción presentes en el comentario, con el objetivo de ponerlas en relación, por un lado, con el Prólogo de Landino y, por otro, con algunas de las concepciones poéticas más importantes del Humanismo peninsular. Adelantamos a manera de conclusión que la particular situación enunciativa desde la que escribe el arcediano, a saber, su calidad de religioso y literato de corte, le confiere a su texto un valor indiscutible en cuanto exponente de las problemáticas culturales más apremiantes del período, en especial la tensión entre la Escolástica y el Humanismo, que su mismo texto, en sus posturas un tanto contradictorias, encarna. Sin embargo, su valor mayor radica en la vital importancia que presenta para la historia de las reflexiones literarias en la Península, pues al mismo tiempo que releva y reformula toda la serie de reflexiones poéticas y tópicos literarios que encuentra en su tradición, presenta actitudes que, a comienzos del siglo XVI, resultan novedosas.La première traduction castillane imprimée de la Divina Commedia (Burgos, 1515 fut accompagnée d'un commentaire exhaustif entourant chaque strophe, dans lequel Pedro Fernández de Villegas a traduit et amplifié le “Comento soprala Commedia” (1481 de Cristoforo Landino. L'objectif du présent article est d'analyser les réflexions concernant la poésie et la fiction que propose le commentaire, afin de les mettre en relation, d'une part, avec le prologue de Landino et, d'autre part, avec certaines des principales conceptions poétiques de l'Humanisme péninsulaire. En guise de conclusion, nous pouvons avancer que la situation

  12. Teatro y memoria: la recreación del mundo rural en Las manos, de José Ramón Fernández, Yolanda Pallín y Javier G. Yagüe

    Directory of Open Access Journals (Sweden)

    Vilches de Frutos, M. Francisca

    2002-06-01

    Full Text Available Current research on twentieth-century Spanish theater reveals a high number of historical plays, a tendency that has continued during the last five years. Some of the most significant writers currently writing for the stage are actively revising the recent past in their work. In this context, three playwrights stand out —Jose Ramon Fernandez, Yolanda Pallin and Javier G. Yague— thanks to the critical and commercial success of their Las manos (Hands, a play about young people who live in a rural area of Spain during the decade of the 1960s. The study of the play's themes and its reception bring to light the reasons behind this historical recreation and the favorable response accorded it by critics and audiences.El análisis de las representaciones escénicas llevadas a cabo en España durante el siglo XX permite apreciar la existencia de un elevado número de obras históricas. Esta tendencia ha tenido continuidad en el último lustro, donde algunos de los más destacados autores dramáticos no han dudado en iniciar una revisión del pasado reciente. En este contexto no debe sorprender el éxito crítico y comercial alcanzado por José Ramón Fernández, Yolanda Pallín y Javier G. Yagüe con Las manos, una obra protagonizada por jóvenes pertenecientes al ámbito rural español en la década de los sesenta. El estudio de sus claves temáticas y de su recepción permitirá explicar las razones para recrear este período histórico y las causas de su excelente acogida.

  13. DNA Probes Show Genetic Variation in Cyanobacterial Symbionts of the Azolla Fern and a Closer Relationship to Free-Living Nostoc Strains than to Free-Living Anabaena Strains

    Science.gov (United States)

    Plazinski, Jacek; Zheng, Qi; Taylor, Rona; Croft, Lynn; Rolfe, Barry G.; Gunning, Brian E. S.

    1990-01-01

    Twenty-two isolates of Anabaena azollae derived from seven Azolla species from various geographic and ecological sources were characterized by DNA-DNA hybridization. Cloned DNA fragments derived from the genomic sequences of three different A. azollae isolates were used to detect restriction fragment length polymorphism among all symbiotic anabaenas. DNA clones were radiolabeled and hybridized against southern blot transfers of genomic DNAs of different isolates of A. azollae digested with restriction endonucleases. Eight DNA probes were selected to identify the Anabaena strains tested. Two were strain specific and hybridized only to A. azollae strains isolated from Azolla microphylla or Azolla caroliniana. One DNA probe was section specific (hybridized only to anabaenas isolated from Azolla ferns representing the section Euazolla), and five other probes gave finer discrimination among anabaenas representing various ecotypes of Azolla species. These cloned genomic DNA probes identified 11 different genotypes of A. azollae isolates. These included three endosymbiotic genotypes within Azolla filiculoides species and two genotypes within both A. caroliniana and Azolla pinnata endosymbionts. Although we were not able to discriminate among anabaenas extracted from different ecotypes of Azolla nilotica, Azolla mexicina, Azolla rubra and Azolla microphylla species, each of the endosymbionts was easily identified as a unique genotype. When total DNA isolated from free-living Anabaena sp. strain PCC7120 was screened, none of the genomic DNA probes gave detectable positive hybridization. Total DNA of Nostoc cycas PCC7422 hybridized with six of eight genomic DNA fragments. These data imply that the dominant symbiotic organism in association with Azolla spp. is more closely related to Nostoc spp. than to free-living Anabaena spp. Images PMID:16348182

  14. «God save us from more revolutions»: the Aranjuez Mutiny and the Dos de Mayo uprising in the light of Count Fernán Núñez’s widow | «Dios nos libre de más revoluciones»: el Motín de Aranjuez y el Dos de Mayo vistos por la condesa viuda de Fernán Núñez

    Directory of Open Access Journals (Sweden)

    Antonio Calvo Maturana

    2011-12-01

    Full Text Available This essay’s objective is to analyse a direct and unpublished testimony of the two biggest Spanish historical events of 1808: the Mutiny of Aranjuez and Dos de Mayo Uprising. With this purpose we present to the public a collection of letters written by Maria Esclavitud Sarmiento, Countess of Fernan Nuñez, and found in the French National Archives of Paris. In this lady’s correspondence we can appreciate the fears, the hopes and the speculations lived and suffered by the people from Madrid during this period. Thanks to this source we have access to the impressions of an eyewitness (a woman, something even more interesting and unusual who was in constant relation with the current situation, gathering news and rumours, sometimes already obsolete in the next letter because of the frenetic political situation. By her contacts with well-informed people (such as her son, the count of Fernan Nuñez, or members of government like Pedro Cevallos or Eusebio Bardaji, the widow countess offers interesting information about the most important figures and events of this year: Ferdinand VII (his rise to the throne and the preparation for his trip to Bayonne, Napoleon (his arrival to Spain and his recognition, or not, of the new king, Manuel Godoy (his imprisonment and his delivery to French authorities, Charles IV (the renounce of his claim and his posterior regret and Marie Louise of Parme (many rumours related to her dark legend. | El objetivo de este trabajo es ofrecer al lector un testimonio directo e inédito de lo acontecido en Madrid durante los dos grandes hitos históricos españoles de 1808: el Motín de Aranjuez y el Dos de Mayo. Para ello utilizaremos principalmente unas cartas de María Esclavitud Sarmiento, condesa viuda de Fernán Núñez, encontradas en los Archivos Nacionales de París. Esta dama de la alta nobleza reflejó en su correspondencia los miedos, esperanzas y especulaciones que asaltaron a la sociedad madrileña del momento. De

  15. Las Teorías de Elton Mayo, La Teoría de las Necesidades Humanas de Abrahan Maslow para Desarrollar las Relaciones Interpersonales, En La Institución Educativa Nº 10103 “Carmen Rosa Fernández Barrera” Del Caserío La Capilla – Pueblo Nuevo - Ferreñafe

    OpenAIRE

    Duran Chambergo, Elizabeth; Ugaz Castillo, Gustavo

    2017-01-01

    El objetivo del trabajo es diseñar estrategias para mejorar las relaciones interpersonales de los directivos y docentes de la Institución Educativa Nº 10103 “Carmen Rosa Fernández Barrera” del Caserío la Capilla – Pueblo Nuevo – Ferreñafe, que permita mejorar la gestión institucional, cuyos indicadores dan cuenta de: a) ineficientes relaciones interpersonales, b) equivocados estilos de dirección, c) falta de comunicación laboral, d) exiguas retribuciones y e) escasa disponibilidad de espacios...

  16. Near-shore distribution of phyllosomas of the two only lobster species (Decapoda: Achelata present in Robinson Crusoe Island and endemic to the Juan Fernández archipelago Distribución costera de filosomas de las dos únicas especies de langostas (Decapoda: Achelata presentes en la Isla Robinson Crusoe y endémicas del archipiélago de Juan Fernández

    Directory of Open Access Journals (Sweden)

    ÁLVARO T PALMA

    2011-09-01

    Full Text Available Two lobster species coexist in the southeast Pacific Juan Fernández archipelago, Jasus frontalis (Milne-Edwards, 1837 and Acantharctus delfini (Bouvier, 1909. Like most lobster species they undergo a prolonged larval period, which is particularly long for J. frontalis (> 16 months. Though typical of Palinurids, this long larval duration is usually not thought to be conducive to local recruitment. While it is known that settlement is confined to the three islands of the archipelago (Robinson Crusoe, Alejandro Selkirk and Santa Clara and Desventuradas Islands (aprox. 800 km to the north, it remains poorly understood how local larval supply allows such distribution pattern. The goal of this study is twofold. Firstly, we aimed to characterize the distribution and abundance of the larvae of these two species around Robinson Crusoe Island using plankton tows and systematic hydrographic records between October 2008 to March of 2011, thus providing the first systematic and prolonged coupled biophysical observations in the nearshore of the archipelago. We hypothesize that spatial and temporal larval distribution patterns are associated to their retention around the archipelago, thus contributing to our knowledge of the physical and biological processes maintaining their extreme isolation. Secondly, using molecular genetics, we confirm a simple taxonomic criteria to distinguish the larvae of the two species, thus aiding future studies of larval dynamics. Throughout phyllosomas of A. delfini were more abundant than that of J. frontalis. Both species were more abundant on the northern shores of Robinson Crusoe Island and generally associated with warmer and saltier waters and mostly present in the samples collected during spring and summer months. Phyllosomas of both species were more abundant during nighttime tows in the upper layer of the water column surveyed suggesting a diurnal vertical migration behavior which, for coastal dwelling meroplanktonic

  17. Biodiesel Production from Azolla filiculoides (Water Fern)

    African Journals Online (AJOL)

    1Department of Microbiology, Rasht Branch, Islamic Azad University, Rasht, Iran, 2Department of Biology, Faculty of ... Conclusion: The results indicate that biodiesel can be produced from ... Consequently, microalgae that can grow rapidly.

  18. Biodiesel Production from Azolla filiculoides (Water Fern ...

    African Journals Online (AJOL)

    Tropical Journal of Pharmaceutical Research. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 13, No 6 (2014) >. Log in or Register to get access to full text downloads.

  19. USE OF BANANA TREE PSEUDOSTEM ENRICHED WITH NITROGEN AND PHOSPHOROUS AS SUBSTRATE FOR CULTIVATION OF FERNS USO DE PSEUDOCAULE DE BANANEIRA ENRIQUECIDO COM NITROGÊNIO E FÓSFORO COMO SUBSTRATO PARA O CULTIVO DE SAMAMBAIAS

    Directory of Open Access Journals (Sweden)

    Suerlani Aparecida Ferreira Moreira

    2009-12-01

    Full Text Available

    The prohibition of the use of xaxim fiber as substrate, because its raw material source (Dicksonia sellowiana was listed as an endangered species, lead to the need of looking for other kinds of substrate. Banana tree cultivation produces a large amount of pseudostem residues, which, due to their physical-chemical characteristics, can be an alternative in substrates composition for ornamental plants, in substitution for xaxim fiber, mainly when associated with fertilizers. This research aimed to evaluate biomass production, nutritional stage, and nutrients availability for ferns, testing substrates in xaxim fiber (XF and banana tree pseudostem (BP, and fertilizations with N and P. The substrate proportions were sand:soil:XF and sand:soil:BP, in a relation of 1:1:2 in volume. Dosages tested were 0 mg dm-3; 68.5 mg dm-3; 137.0 mg dm-3; 205.5 mg dm-3; and 374.0 mg dm-3 of N and 0 mg dm-3; 97.7 mg dm-3; 195.4 mg dm-3; 291.9 mg dm-3; and 390.8 mg dm-3 of P2O5. The number of leaves produced by the fern did not differ significantly in response to substrates or N and P dosages. The same result was verified in most of the substrate and plant mineral evaluations. It was concluded that banana tree pseudostem could perfectly replace xaxim fiber as substrate component for ferns.

  20. Caracterização etnobotânica dos sistemas de manejo de samambaia-preta (Rumohra adiantiformis (G. Forst Ching - Dryopteridaceae utilizados no sul do Brasil Ethnobotanical characterization of leatherleaf fern (Rumohra adiantiformis (G. Forst Ching - Dryopteridaceae management systems used in southern Brazil

    Directory of Open Access Journals (Sweden)

    Cristina Baldauf

    2007-12-01

    Full Text Available (Caracterização etnobotânica dos sistemas de manejo de samambaia-preta (Rumohra adiantiformis (G. Forst Ching - Dryopteridaceae utilizados no sul do Brasil. A samambaia-preta (Rumohra adiantiformis (G. Forst Ching- Pteridophyta é utilizada comercialmente na produção de arranjos florais. A extração desta espécie é fonte de renda de muitas famílias da região sul do Brasil. O objetivo deste estudo foi caracterizar os sistemas de manejo da espécie utilizados no Estado do Rio Grande do Sul (RS através do uso de entrevistas semi-estruturadas e observação participante com famílias extrativistas do município de Maquiné-RS. Foi verificada a ocorrência de uma grande diversidade de técnicas de manejo, a partir da qual foi proposta uma tipologia de sistemas de manejo. A tipologia consiste em quatro sistemas de manejo principais, de acordo com o manejo da paisagem e das populações de samambaia empregados. Constatou-se uma associação entre a situação fundiária e os sistemas de manejo utilizados. Nas terras arrendadas é realizada apenas a coleta das frondes, enquanto nas terras próprias são realizadas intervenções como podas, derrubadas de árvores, retirada de frondes mortas, pisoteio da área após coleta, além de interação com sistemas de agricultura de coivara e criação de gado. A tipologia dos sistemas de manejo elaborada, em associação com outros estudos sobre a sustentabilidade do extrativismo de samambaia-preta, vem fundamentando a regulamentação desta atividade no Rio Grande do Sul.(Ethnobotanical characterization of leatherleaf fern (Rumohra adiantiformis (G. Forst Ching - Dryopteridaceae management systems used in southern Brazil. The leatherleaf fern (Rumohra adiantiformis (G. Forst. Ching is commercially used in flower arrangements. The harvesting of this species is an income source for many families from southern Brazil. The aim of this study was to characterize species management systems used in Maquin

  1. Land Cover Change in the Andes of Southern Ecuador—Patterns and Drivers

    Directory of Open Access Journals (Sweden)

    Giulia F. Curatola Fernández

    2015-03-01

    Full Text Available In the megadiverse tropical mountain forest in the Andes of southern Ecuador, a global biodiversity hotspot, the use of fire to clear land for cattle ranching is leading to the invasion of an aggressive weed, the bracken fern, which is threatening diversity and the provisioning of ecosystem services. To find sustainable land use options adapted to the local situation, a profound knowledge of the long-term spatiotemporal patterns of land cover change and its drivers is necessary, but hitherto lacking. The complex topography and the high cloud frequency make the use of remote sensing in this area a challenge. To deal with these conditions, we pursued specific pre-processing steps before classifying five Landsat scenes from 1975 to 2001. Then, we quantified land cover changes and habitat fragmentation, and we investigated landscape changes in relation to key spatial elements (altitude, slope, and distance from roads. Good classification results were obtained with overall accuracies ranging from 94.5% to 98.5% and Kappa statistics between 0.75 and 0.98. Forest was strongly fragmented due to the rapid expansion of the arable frontier and the even more rapid invasion by bracken. Unexpectedly, more bracken-infested areas were converted to pastures than vice versa, a practice that could alleviate pressure on forests if promoted. Road proximity was the most important spatial element determining forest loss, while for bracken the altitudinal range conditioned the degree of invasion in deforested areas. The annual deforestation rate changed notably between periods: ~1.5% from 1975 to 1987, ~0.8% from 1987 to 2000, and finally a very high rate of ~7.5% between 2000 and 2001. We explained these inconstant rates through some specific interrelated local and national political and socioeconomic drivers, namely land use policies, credit and tenure incentives, demography, and in particular, a severe national economic and bank crisis.

  2. Detecting changes in insect herbivore communities along a pollution gradient

    International Nuclear Information System (INIS)

    Eatough Jones, Michele; Paine, Timothy D.

    2006-01-01

    The forests surrounding the urban areas of the Los Angeles basin are impacted by ozone and nitrogen pollutants arising from urban areas. We examined changes in the herbivore communities of three prominent plant species (ponderosa pine, California black oak and bracken fern) at six sites along an air pollution gradient. Insects were extracted from foliage samples collected in spring, as foliage reached full expansion. Community differences were evaluated using total herbivore abundance, richness, Shannon-Weiner diversity, and discriminant function analysis. Even without conspicuous changes in total numbers, diversity or richness of herbivores, herbivore groups showed patterns of change that followed the air pollution gradient that were apparent through discriminant function analysis. For bracken fern and oak, chewing insects were more dominant at high pollution sites. Oak herbivore communities showed the strongest effect. These changes in herbivore communities may affect nutrient cycling in forest systems. - Differences in insect herbivore communities were associated with an ambient air pollution gradient in the mixed conifer forest outside the Los Angeles area

  3. Detecting changes in insect herbivore communities along a pollution gradient

    Energy Technology Data Exchange (ETDEWEB)

    Eatough Jones, Michele [Department of Entomology, University of California Riverside, Riverside, CA 92521 (United States)]. E-mail: michele.eatough@ucr.edu; Paine, Timothy D. [Department of Entomology, University of California Riverside, Riverside, CA 92521 (United States)]. E-mail: timothy.paine@ucr.edu

    2006-10-15

    The forests surrounding the urban areas of the Los Angeles basin are impacted by ozone and nitrogen pollutants arising from urban areas. We examined changes in the herbivore communities of three prominent plant species (ponderosa pine, California black oak and bracken fern) at six sites along an air pollution gradient. Insects were extracted from foliage samples collected in spring, as foliage reached full expansion. Community differences were evaluated using total herbivore abundance, richness, Shannon-Weiner diversity, and discriminant function analysis. Even without conspicuous changes in total numbers, diversity or richness of herbivores, herbivore groups showed patterns of change that followed the air pollution gradient that were apparent through discriminant function analysis. For bracken fern and oak, chewing insects were more dominant at high pollution sites. Oak herbivore communities showed the strongest effect. These changes in herbivore communities may affect nutrient cycling in forest systems. - Differences in insect herbivore communities were associated with an ambient air pollution gradient in the mixed conifer forest outside the Los Angeles area.

  4. Seamounts in the southeastern Pacific Ocean and biodiversity on Juan Fernandez seamounts, Chile Montes submarinos en el océano Pacífico suroriental y biodiversidad en el cordón de Juan Fernández, Chile

    Directory of Open Access Journals (Sweden)

    Eleuterio Yáñez

    2009-01-01

    Full Text Available Seamounts are vulnerable marine ecosystems. In Chile, information on these ecosystems is quite scarce; thus, a compilation of information on their geographical distribution and biodiversity is presented herein. A total of 118 seamounts distributed in the Chilean EEZ are identified and characterized. Additionally, an in situ assessment was carried out on the Juan Fernandez seamounts 1 and 2 (JF1 and JF2, which were also oceanographically characterized. Phytoplankton, zooplankton, and marine invertebrate samples were collected and an exploratory fishing survey was executed using different gears. According to the bibliographical review, a total of 82 species have been collected on the JF1 and JF2 seamounts, highlighting fmdings of black coral species caught in lobster traps at the Juan Fernandez Archipelago. Submarine images of the marine substrate at JF1 and JF2 reveal characteristics attributable to the impact of bottom dredges, coinciding with the information obtained from the trawling fleet. The fishing activity was carried out primarily at JF2 (4,667 km of trawling. The monthly fishing effort increased considerably in 2002, 2003, and 2005, reaching values above 500 km of trawling and, thus, modifying the spatial structure of the resource aggregates on the JF2 seamount.Los montes submarinos constituyen ecosistemas marinos vulnerables. Chile presenta una escasa información acerca de estos ecosistemas, por lo que este trabajo recopila información sobre distribución geográfica y biodiversidad. Se identifican y caracterizan 118 montes en la ZEE de Chile. Adicionalmente, una evaluación in situ se desarrolló sobre los montes Juan Fernández 1 y 2 (JF1, JF2, caracterizándolos oceanógraficamente. Se recolectaron muestras de fitoplancton, zooplancton e invertebrados marinos, y se realizó pesca exploratoria con diversos artes. La revisión bibliográfica establece que en JF1 y JF2, se han capturado un total de 82 especies, destacándose la

  5. Degradation kinetics of ptaquiloside in soil and soil solution.

    Science.gov (United States)

    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.

  6. Conjunto de técnicas de motivación para elevar la práctica del ejercicio físico en edades de 30 a 50 años del sexo femenino en el Reparto Ceferino Fernández

    Directory of Open Access Journals (Sweden)

    Marlen de la Caridad Labrador Vento

    2009-09-01

    Full Text Available La poca motivación del sexo femenino por la práctica del ejercicio físico, y más significativo en la edades de 30 a 50 años, es algo muy generalizado en las comunidades del municipio de Pinar del Río. Para darle solución a esta situación, se realizó un estudio de los motivos por los cuales las féminas no practican el ejercicio físico, en el consultorio # 38 del Reparto Ceferino Fernández, y se obtuvo como resultado fundamentalmente la falta de comunicación e información de la importancia que reviste para elevar la calidad de vida, la práctica sistemática del ejercicio físico, por parte de los diferentes factores de la comunidad, del profesor de cultura física y del médico del consultorio. Todo ello estuvo sustentado a través del uso de diferentes métodos investigativos, los que permitieron potenciar los criterios expresados por diferentes autores acerca de la motivación por las actividades y la importancia de la práctica del ejercicio físico.

  7. Composition, community structure and vertical distribution of epiphytic ferns on Alsophila setosa Kaulf., in a Semideciduous Seasonal Forest, Morro Reuter, RS, Brazil Composição, estrutura comunitária e distribuição vertical de samambaias epifíticas sobre Alsophila setosa Kaulf. (Cyatheaceae, em Floresta Estacional Semidecidual, Morro Reuter, RS, Brasil

    Directory of Open Access Journals (Sweden)

    Paulo Henrique Schneider

    2011-09-01

    Full Text Available In tropical forests, tree ferns constitute an important phorophyte for the establishment and occurrence of epiphytic species. Composition, structure and vertical distribution of epiphytic ferns were studied on Alsophila setosa Kaulf., in a semideciduous seasonal forest fragment, in the city of Morro Reuter (29º32'07"S and 51º05'26"W, in the state of Rio Grande do Sul, Brazil. The sample consisted of 60 caudices of at least 4 m high, which were divided in 1 m intervals from the ground. The specific importance value was estimated trough the coverage value and caudex frequency at the intervals. A total of 14 species was recorded, belonging to 10 genera and five families. The highest specific richness occurred in Polypodiaceae. The rarefaction curve for the total sample did not reach an asymptote with an estimated 14.98 to 16.95 species, showing that a few species could still be recorded. The species with the highest importance value and vertical amplitude was Blechnum binervatum (Poir. C.V. Morton & Lellinger, with a decreasing frequency from bottom to top of the caudex. Considering the predominance of habitual holoepiphytes, the removal of Alsophila setosa caudices compromises microhabitat availability for epiphytes in the forest understory.Nas florestas tropicais as samambaias arborescentes constituem forófitos importantes para o estabelecimento e ocorrência de espécies epifíticas. A composição, a estrutura e a distribuição vertical de samambaias epifíticas foram estudadas sobre Alsophila setosa Kaulf., em fragmento de Floresta Estacional Semidecidual, localizado no município de Morro Reuter (29º32'07"S e 51º05'26"W, Rio Grande do Sul, Brasil. Foram amostrados 60 cáudices de no mínimo 4 m de altura e eles foram divididos em intervalos de 1 m, a partir do solo. O valor de importância específico foi estimado a partir da freqüência nos cáudices , nos intervalos e do valor de cobertura. Foram registradas 14 espécies epif

  8. Rendimientos, estructuras de tallas y madurez sexual del alfonsino (Beryx splendens capturado en el cordón submarino de Juan Fernández, Chile Fishing yields, size structures, and sexual maturity of alfonsino (Beryx splendens caught on Juan Fernandez seamounts, Chile

    Directory of Open Access Journals (Sweden)

    Aurora Guerrero

    2009-01-01

    Full Text Available Se analiza la información recopilada en lances comerciales para la captura de alfonsino (Beryx splendens realizados en montes submarinos del archipiélago de Juan Fernández (Chile, entre los años 2001 y 2003, que corresponden a la etapa de desarrollo inicial de esta pesquería. En dicho período se efectuaron 187 lances, de los cuales en 121 se obtuvo la especie objetivo, capturándose 525,1 ton, que constituyeron el 99,2% de la captura total. Por la configuración irregular de los fondos, los lances de pesca se caracterizaron por su corta duración (0,26-0,50 h, a profundidad media de 469,7 m. En este periodo se analizaron 14.773 ejemplares, 6.064 machos (41% y 8.709 hembras (59%, evidenciando un predominio de hembras. La proporción sexual estructurada a la talla mostró un predominio de machos a tallas inferiores a 24 cm de longitud de horquilla (LH. En machos el tamaño medio fluctuó entre 34,6 y 36,8 cm de LH y en hembras entre 36,2 y 38,4 cm LH. Para determinar la madurez de las gónadas, se utilizó la escala macroscópica propuesta por Lehodey et al. (1997 y se estableció que los machos alcanzaron la primera madurez (TMS50% a 34,3 cm LH y las hembras a los 33,3 cm LH. Los rendimientos promedio en el período analizado correspondieron entre 0,2 y 6,6 ton lance-1 y entre 1,8 y 19,0 ton h.a.-1 , con medias de 4,3 ton lance-1 y 9,2 ton h.a.-1 .We analyzed information collected during commercial hauls targeting alfonsino (Beryx splendens on seamounts of the Juan Fernández Archipelago (Chile from the early stages of the fishery (2001-2003. Of the 187 hauls carried out in this period, 121 were successful; alfonsino catches reached 525.1 ton, constituting 99.2%> of the total catch. Due to the irregularity of the sea bottom, short (0.26-0.50 h fishing hauls were performed at mid-depth (469.7 m. We analyzed 14,773 specimens during the study period: 6,064 males (41% and 8,709 females (59%, the latter being predominan! The size structure was

  9. Entrevista con prof. Noberto Fernández Lamarra: La universidad en Brasil y Argentina en perspectiva comparada: hacia un espacio común Latinoamericano de educación superior en el marco de la internacionalización de la educación

    Directory of Open Access Journals (Sweden)

    Noberto Fernández Lamarra

    2017-07-01

    Full Text Available El profesor Norberto Fernández Lamarra es profesor de posgrado, investigador y consultor nacional e internacional en el área de las políticas, la planificación,  la gestión y la evaluación de la educación –particularmente con perspectiva comparada-, con énfasis en los últimos años en la educación superior.  Actualmente es Director de Posgrados en la Universidad Nacional de Tres de Febrero, en Buenos Aires, Argentina, donde, además, dirige el Núcleo Interdisciplinario de Formación y Estudios para el Desarrollo de la Educación (NIFEDE, el Doctorado en Políticas y Gestión de la Educación Superior y el Programa de Posgrados en Políticas y Administración de la Educación (Maestrías y Especializaciones. Es Presidente de la Sociedad Argentina de Educación Comparada y ha sido Vicepresidente del Consejo Mundial de Sociedades de Educación Comparada, entre los años 2010 y 2016 (UCCES y Presidente fundador de la Sociedad Iberoamericana de Educación Comparada (SIBEC. Dirige las revistas académicas Revista Argentina de Educación Superior (RAES, Revista Latinoamericana de Educación Comparada (RELEC y Revista Latinoamericana de Política y Administración de la Educación (RELAPAE.

  10. Evaluation of the concentrations of rare earth elements, uranium and thorium in the soil-plant system by Neutron Activation, k{sub 0} method

    Energy Technology Data Exchange (ETDEWEB)

    Moura, Rodrigo Reis de, E-mail: rodrigoreismoura@gmail.com [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Programa de Pós-Graduação em Ciências e Técnicas Nucleares; Menezes, Maria Ângela de Barros Correia, E-mail: menezes@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (SERTA/CDTN/CNEN-MG), Belo Horizonte, MG (Brazil). Serviço de Técnicas Analíticas; Marques, Douglas José, E-mail: douglasjmarques81@yahoo.com.br [Universidade José do Rosário Vellano (Unifenas), Alfenas, MG (Brazil). Setor de Olericultura e Experimentação em Agricultura Orgânica

    2017-07-01

    The nuclear technique Neutron Activation Analysis (NAA) has improved results in a wide range of research fields, since it is a sensitive technique to determine very low concentrations at the trace level in several matrices.The k0 standardized is a NAA method that has been outstanding in the last decades because there is not the inconvenience of using standards for the elements of interest in the analysis. This increases the accuracy of the method and decreases the uncertainties in the obtained results. In this assessment, the NAA was applied to determine the rare earth elements (REEs), U and Th concentrations in plant and soil samples from a mining area. The data obtained by k0-method were used to calculate the amount of the concentrations of these elements present in the sample soil that were uptaken and fractionated in the studied plants by parameters commonly used, the Transfer Factor (TF) and Bio-concentration Coefficient (BC). The results showed that TF was slightly enriched to REEs (mainly La and Nd) and U and depleted to Th. The results presented to BC confirmed that among plant organs the root accumulated higher REEs concentration levels (root > stem > leaf) and on leaves were not detected Sm (Baccharis crispa), Eu (Baccharis crispa and Tibouchina granulosa) and Yb (Pteridium arachnoideum). Among species studied, Pteridium arachnoideum (fern) was the one that most uptaken and accumulated REEs, U and Th. (author)

  11. Evaluation of the concentrations of rare earth elements, uranium and thorium in the soil-plant system by Neutron Activation, k0 method

    International Nuclear Information System (INIS)

    Moura, Rodrigo Reis de; Menezes, Maria Ângela de Barros Correia; Marques, Douglas José

    2017-01-01

    The nuclear technique Neutron Activation Analysis (NAA) has improved results in a wide range of research fields, since it is a sensitive technique to determine very low concentrations at the trace level in several matrices.The k0 standardized is a NAA method that has been outstanding in the last decades because there is not the inconvenience of using standards for the elements of interest in the analysis. This increases the accuracy of the method and decreases the uncertainties in the obtained results. In this assessment, the NAA was applied to determine the rare earth elements (REEs), U and Th concentrations in plant and soil samples from a mining area. The data obtained by k0-method were used to calculate the amount of the concentrations of these elements present in the sample soil that were uptaken and fractionated in the studied plants by parameters commonly used, the Transfer Factor (TF) and Bio-concentration Coefficient (BC). The results showed that TF was slightly enriched to REEs (mainly La and Nd) and U and depleted to Th. The results presented to BC confirmed that among plant organs the root accumulated higher REEs concentration levels (root > stem > leaf) and on leaves were not detected Sm (Baccharis crispa), Eu (Baccharis crispa and Tibouchina granulosa) and Yb (Pteridium arachnoideum). Among species studied, Pteridium arachnoideum (fern) was the one that most uptaken and accumulated REEs, U and Th. (author)

  12. Nuclear microscopy of biological specimens

    International Nuclear Information System (INIS)

    Watt, F.; Grime, G.W.; Brook, A.J.; Gadd, G.M.; Perry, C.C.; Pearce, R.B.; Turnau, K.; Watkinson, S.C.

    1991-01-01

    Recent developments in technology have enabled the scanning proton microprobe to scan at submicron spatial resolution on a routine basis. The use of the powerful combination of techniques PIXE (proton induced X-ray emission), nuclear (or Rutherford) backscattering (RBS), and secondary electron detection operating at this resolution will open up new areas in many scientific disciplines. This paper describes some of the work carried out in the biological sciences over the last year, using the Oxford SPM facility. Collaborations with biological scientists have drawn attention to the wealth of information that can be derived when these techniques are applied to micro-organisms, cells and plant tissue. Briefly described here are investigations into the uptake of heavy metals by the alga Pandorina morum, the structure of the diatom Stephanopyxis turris, the presence of various types of crystal structures within the cells of Spirogyra, the heavy metal uptake of a mycorrhizal fungus present in the bracken (Pteridium aquilinum) root, the role of sphagnum moss in the absorption of inorganic elements, the measurement of heavy metals in environmentally-adapted cells of the yeast Saccharomyces cerevisiae, and the elemental distribution in the growing tip of a spore from the plant Equisetum arvense, with special emphasis placed on the visual interpretation of the elemental and secondary-electron maps provided by the nuclear microscopical techniques. (orig.)

  13. 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.

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  16. Transfer of radionuclides to plants[Radioecology

    Energy Technology Data Exchange (ETDEWEB)

    Nielsen, Sven P. [Risoe National Lab., Roskilde (Denmark)

    2006-04-15

    Sampling of Water Horsetail and Bracken Fern including upper soil layer (0-10 cm) and water was carried out in Torahult, Sweden, in Almindingen on Bornholm, in Asserbo and Arresoe on Zealand and in Sdr. Hostrup and Nydam mose in Jutland. Furthermore, sampling was carried out in 2004 for seawater, seaweed and shrimps at locations in Danish waters at Bornholm (Svenskehavn), at Zealand (Klint), at Lolland/Falster (Guldborgsund) and on the west coast of Jutland (Hirtshals, Agger, Hvide Sande and Roemoe). Concentrations of gamma-emitting radionuclides and uranium were determined in Bracken Fern, Water Horsetail and soil samples. The concentration ratios (CR) are highest for {sup 40}K in both plant species and show the lowest variability across locations. The CR's for 40K range from 1 to 2, while the CR's for the other radionuclides range one to three orders of magnitude lower. The CR's for {sup 137}Cs show particularly high variability across locations. The CR's were analysed in a two-way ANOVA on the log-transformed values to test differences between plant species and radionuclides. The difference between radionuclides was highly significant, p<0.01, whereas the difference between plant species was not significant. The concentration ratios are listed by radionuclide showing geometric mean values and geometric standard deviations. Analyses were made of {sup 137}Cs and {sup 99}Tc in marine samples. Concentration ratios calculated from the analysed samples are presented. The concentration ratios for {sup 99}Tc agree with those reported elsewhere in the Indofern Project. The concentration ratios for {sup 137}Cs in Fucus show a correlation to salinity with higher values in low salinity water at Bornholm than in high salinity water on the west coast of Jutland. (LN)

  17. The fern herbarium at the Komarov Botanical Institute, Leningrad

    NARCIS (Netherlands)

    Holttum, R.E.

    1977-01-01

    The Herbarium is arranged according to Christensen’s Index Filicum (1905). I examined all the Old World specimens in Dryopteris and Aspidium, both in the general herbarium and in the separate herbarium for China and Japan. It appears that the genera segregated by Christensen from Dryopteris (e.g.

  18. Taxonomic revision of the Palaeozoic marattialean fern Acithea Schimper

    Czech Academy of Sciences Publication Activity Database

    Zodrow, E. L.; Šimůnek, Z.; Cleal, Ch. J.; Bek, Jiří; Pšenička, J.

    2006-01-01

    Roč. 138, 3-4 (2006), s. 239-280 ISSN 0034-6667 R&D Projects: GA AV ČR IAA3013902 Institutional research plan: CEZ:AV0Z30130516 Keywords : Permo-Carboniferous * Acitheca * Marattiales * epiderms * in situ spores Subject RIV: EF - Botanics Impact factor: 1.170, year: 2006

  19. First megafossil evidence of Cyatheaceous tree fern from the Indian ...

    Indian Academy of Sciences (India)

    the Plio–Pleistocene and this group subsequently declined in importance within the local vegetation. 1. Introduction .... The vascular system ... from the early Cretaceous of Korea and Philippines, ... is acknowledged for financial assistance.

  20. Givetian (Middle Devonian) cladoxylopsid 'ferns' from Orkney, Northern Scotland

    OpenAIRE

    Berry, Christopher Mark; Hilton, Jason

    2006-01-01

    Two large fossil plants are described from the Givetian (Middle Devonian) Eday\\ud Flags, South Ronaldsay, Orkney Isles, northern Scotland. Fossils with branches joined to stems of\\ud this age are rare. Each specimen comprises a robust and tapering main trunk from which numerous\\ud closely spaced branches arise distally. Although poorly preserved such that generic identifications are\\ud not possible, both specimens display the characteristic architecture of the plant order Pseudosporochnales\\u...

  1. Solar energy system economic evaluation: Fern Tunkhannock, Tunkhannock, Pennsylvania

    Science.gov (United States)

    1980-01-01

    The economic performance of an Operational Test Site (OTS) is described. The long term economic performance of the system at its installation site and extrapolation to four additional selected locations to demonstrate the viability of the design over a broad range of environmental and economic conditions is reported. Topics discussed are: system description, study approach, economic analysis and system optimization, and technical and economical results of analysis. Data for the economic analysis are generated through evaluation of the OTS. The simulation is based on the technical results of the seasonal report simulation. In addition localized and standard economic parameters are used for economic analysis.

  2. Dryopsis (Dryopteridaceae, A Fern Genus New to Vietnam

    Directory of Open Access Journals (Sweden)

    Hui-Hui Ding

    2013-03-01

    Full Text Available Dryopsis clarkei (Baker Holttum & P.J. Edwards, representing the whole genus, is reported new to Vietnam. A detailed description, including the variation of gross morphology, spore morphology, and chromosome counts, is provided by means of words as well as photographs or drawings. Dryopsis clarkei is for the first time demonstrated to be a sexual diploid (2n = 82, with rather stable morphology except for the length of stipe.

  3. Aquatic Fern (Azolla Sp.) Assisted Synthesis of Gold Nanoparticles

    Science.gov (United States)

    Jha, Anal K.; Prasad, K.

    2016-02-01

    Aquatic pteridophyte (Azolla sp.) was taken to assess its potential to synthesize the metal (Au) nanoparticles. The synthesized particles were characterized using X-ray, UV-visible, scanning and transmission electron microscopy analyses. Nanoparticles almost spherical in shape having the sizes of 5-17nm are found. UV-visible study revealed the surface plasmon resonance at 538nm. Responsible phytochemicals for the transformation were principally phenolics, tannins, anthraquinone glycosides and sugars present abundantly in the plant thereby bestowing it adaptive prodigality. Also, the use of Azolla sp. for the synthesis of gold nanoparticles offers the benefit of eco-friendliness.

  4. Diaspididae (Hemiptera, Coccoidea in sori of two fern species

    Directory of Open Access Journals (Sweden)

    Marcelo Santos

    2015-12-01

    Duas Espécies de Cochonilhas (Hemiptera: Diaspididae Associadas com Soros de Samambaias Resumo. A presente comunicação relata a presença de duas espécies de cochonilhas Hemiberlesia palmae (Cockerell e Pinnaspis strachani (Cooley (Coccoidea, Diaspididae, associadas respectivamente com Asplenium serratum L. (Aspleniaceae e Niphidium crassifolium (L. Lellinger (Polypodiaceae. É o primeiro registro de uma samambaia como planta hospedeira de Hemiberlesia palmae.  Nas duas espécies de samambaias, os diaspidídeos encontravam-se concentrados principalmente ao redor dos soros.

  5. TREE-FERNS OF THE GENUS CYATHEA IN JAVA

    Directory of Open Access Journals (Sweden)

    R. E. HOLTTUM

    2015-10-01

    Full Text Available A full taxonomic study of the genus Cyathea has recently been publish-ed in Flora Malesiana (Ser. II, vol. 1, part 2, Dec. 1963. In that work thegenus is construed in a broad sense, to include Alsophila and Hemitelia(also Gymnosphaera and Schizocaena of Copeland's Genera Filicum, theotal number of species being 191, and a new subdivision of this compre-hensive genus is proposed. The keys in Flora Malesiana, dealing with sucha large number of species, are complex, and not very easy to use for localpurposes. I have therefore made a simpler key to cover the species ofava only, and hope this will be of service to botaniists in Java.

  6. El juego de baloncesto modificado como un medio recreativo para los jóvenes entre 17 y 23 años sexo masculino de la zona 24 de la circunscripción Ceferino Fernández del municipio pinar del Río

    Directory of Open Access Journals (Sweden)

    Marilin Páez Basabe

    2009-06-01

    Full Text Available En los marcos específicos de la participación comunitaria esta se activa y se desarrolla en nexo con los objetivos de la política social estratégicamente diseñadas, nuestro país las investigaciones sobre las recreación física participativa surgen como una necesidad indispensable a consecuencia del proceso de desarrollo económico socia lo que ha  alcanzadas en últimos años la consolidación de la revolución cubana. La presente tesis tiene sus raíces en las contradicciones existentes entre lo ideal un disfrute pleno recreativo de los jóvenes a partir de su preferencias cubriendo en Gan medida sus necesidades , lo real la existencia de esas motivaciones  que  permitan  la  recreación física  placentera  acorde  a  los principios de la sociedad que permita elevar la calidad de vida de una forma sana  placentera  nos  proponemos  para  darle  tratamiento  al  problema presentado la utilización del juego de baloncesto como medio recreativo para los  jóvenes  entre  17  y  23  años  .Objetivos  general:  Diseñar  las  variantes manipulativas  a utilizar en  el juego de baloncesto modificado como un medio recreativo  para los jóvenes entre 17 y 23 años de edad del  sexo masculino de la zona 24 del circunscripción Ceferino Fernández  del municipio pinar del Rió Aportes  teóricos : Contribución a la  teoría: se definen los conceptos fundamentales que da origen ala investigación juego de baloncesto modificado como un medio recreativo y este lleva implicitotas definiciones a seguir en las variables  manipulativas  aporte  practico:  La  recreación  física   a  través  del deporte simplificado para la comunidad Novedad científica: La creación de una instalación de baloncesto rústica para el juego modificado dentro  de  la  comunidad  propiciando  a  diario  un  espectáculo  deportivo recreativo para todos en la actualidad. El rescate del deporte como medio de

  7. Effects of sucrose and irradiance on germination and early gametophyte growth of the endangered tree fern Dicksonia sellowiana Hook (Dicksoniaceae Efeito da sacarose e irradiância na germinação e crescimento inicial do gametófito da samambaia arbórea Dicksonia sellowiana Hook (Dicksoniaceae em perigo de extinção

    Directory of Open Access Journals (Sweden)

    Gladys Daniela Rogge Renner

    2004-06-01

    Full Text Available It is an endangered tree fern that grows in mixed umbrophylus forests in the tropics. Sterilized spores were germinated at 25 ± 2ºC under a 16-hour photoperiod, in Dyer and MS medium supplemented with 0 to 5% sucrose. The germination was lower with the addition of sucrose. Dry mass was higher in 30-day-old gametophytes cultivated in Dyer medium with the addition of 3 to 5% of sucrose. The dry mass decreased in 30-day-old gametophytes cultivated in Dyer and MS media without sucrose and in MS medium with the addition of 4 or 5% of sucrose. The effect of different irradiance on the germination and early gametophyte development of D. sellowiana was analyzed in the autumn of 1998 (May until July. Conical flasks containing spores were kept over a period of 49 days in 50cm³ boxes covered with black shade netting, which gave 5, 20, 36 and 50% of irradiance. The lower mean germination time was observed for spores cultivated under 5% and 20% of irradiance. The highest chlorophyll content was recorded in gametophytes cultivated for 49 days under 20% and 5% of irradiance .The highest soluble sugar content was recorded in gametophytes cultivated under 5% and 20% of irradiance.Esta samambaia arbórea ameaçada de extinção ocorre na floresta ombrófila mista, nos trópicos. Esporos esterilizados germinaram a 25 ± 2ºC em fotoperíodo de 16 horas, em meios de Dyer e MS, acrescidos de 0 a 5% de sacarose. A massa seca foi maior em gametófitos de 30 dias de idade, cultivados em meio Dyer com adição de 3% a 5% de sacarose e em meio MS com adição de 2% de sacarose. A massa seca diminuiu em gametófitos crescidos em meios Dyer e MS na ausência de sacarose e em meio MS acrescido de 5% de sacarose. O efeito de diferentes irradiâncias na germinação e desenvolvimento inicial de gametófitos foi analisado no outono de 1998 (de maio a julho. Frascos cônicos contendo esporos foram mantidos durante 49 dias dentro de caixas de 50cm³ revestidas por telas que

  8. Ciclo anual de la clorofila-α satelital en el archipiélago de Juan Fernández (33°S, Chile Annual cycle of the satellite chlorophyll-a in the Juan Fernandez archipelago (33°S, Chile

    Directory of Open Access Journals (Sweden)

    Isabel Andrade

    2012-09-01

    Full Text Available La variabilidad espacial y temporal del ciclo anual de la clorofila-α en el archipiélago de Juan Fernández se analiza usando ocho anos de datos satelitales de clorofila-α, viento, corrientes y nivel del mar. Este archipiélago está conformado por tres islas: Robinson Crusoe-Santa Clara (RC-SC y Alejandro Selkirk (AS. Las islas RC-SC se encuentran en una región de alta energía cinética y mayores concentraciones de clorofila-α definida como Zona de Transición Costera, en cambio la isla AS se encuentra en una región de baja energía cinética y menores concentraciones de clorofila-α denominada Zona Oceánica. RC-SC posee un incremento de las concentraciones de clorofila-a en el lado suroeste, mientras que AS posee sus mayores concentraciones en el lado oeste, indicando la presencia de procesos forzantes diferentes. En ambas islas el ciclo anual de la clorofila es significativo y comienza a incrementar en abril, alcanzando valores relativamente altos entre junio y noviembre, disminuyendo hacia diciembre, hasta alcanzar un mínimo hacia fines de marzo. Este ciclo anual aparece desacoplado con el viento y acoplado con la energía cinética. Incrementos invernales de clorofila-a aparecen vinculados con remolinos de mesoescala provenientes de la zona continental, mientras que incrementos primaverales se podrían asociar a procesos locales vinculados al "efecto masa de isla". En ambas islas existen incrementos significativos de la clorofila-a en la banda anual y cuasi-bianual, pero sólo en AS se encontró una fluctuación significativa en la banda interanual vinculada con el Nino y la Oscilación del Sur.The spatial and temporal variability of the annual cycle of chlorophyll-a in the Juan Fernandez archipelago is analyzed through eight years of satellite data of chlorophyll-a, wind, currents and sea level. This archipelago consists of three islands: Robinson Crusoe-Santa Clara (RC-SC and Alexander Selkirk (AS. The RC-SC islands are in a

  9. Generation of dose-response relationships to assess the effects of acidity in precipitation on growth and productivity of vegetation

    International Nuclear Information System (INIS)

    Evans, L.S.

    1981-01-01

    Experiments were performed with several plant species in natural environments as well in a greenhouse and/or tissue culture facilities to establish dose-response functions of plant responses to simulated acidic rain in order to determine environmental risk assessments to ambient levels of acidic rain. Response functions of foliar injury, biomass of leaves and seed of soybean and pinto beans, root yields of radishes and garden beets, and reproduction of bracken fern are considered. The dose-response function of soybean seed yields with the hydrogen ion concentration of simulated acidic rainfalls was expressed by the equation y = 21.06-1.01 log x where y = seed yield in grams per plant and x = the hydrogen concentration if μeq l -1 . The correlation coefficient of this relationship was -0.90. A similar dose-response function was generated for percent fertilization of ferns in a forest understory. When percent fertilization is plotted on logarithmic scale with hydrogen ion concentration of the simulated rain solution, the Y intercept is 51.18, slope -0.041 with a correlation coefficient of -0.98. Other dose-response functions were generated that assist in a general knowledge as to which plant species and which physiological processes are most impacted by acidic precipitation. Some responses did not produce convenient dose-response relationships. In such cases the responses may be altered by other environmental factors or there may be no differences among treatment means

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

    Science.gov (United States)

    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.

  11. Avaliação de biofertilizantes, extratos vegetais e diferentes substâncias alternativas no manejo de tripes em cebola em sistema orgânico Evaluation of biofertilizers, plant extracts, and some alternative substances to manage onion thrips in organic agriculture system

    Directory of Open Access Journals (Sweden)

    Paulo A.S. Gonçalves

    2004-09-01

    biofertilizer at 50%, aerobic liquid biofertilizer at 5%, manganese sulfate at 1%, hydroalcoholic extract of propolis at 0,2%, macerate of herbs at 2% and 4%, tobacco extract (Nicotiana tabacum 2 L ha-1 + neutral detergent at 1%, and no spray. In 1997, the treatments were: macerate of herbs 5% and 10%; sulfur waterable powder 0,25% + propolis hydroalcoholic extract 0,2% + extract of fern (Pteridium aquilinum 3%; anaerobic liquid biofertilizer 50%; extract of wormseed goosefoot (Chenopodium ambrosioides 10%; aerobic liquid biofertilizer 5%; extract of Ateleia glazioviana 0,5%; extract of fern (Pteridium aquilinum 10%; extract of chinaberry (Melia zedarach 10%; extract of camomile (Matricaria chamomilla 5%; and control without spray. The products were applied using a CO2 sprayer with constant pressure. The different treatments did not cause significant reduction in the thrips population nor any increase in yield in comparison to control treatment, without spray.

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

    Science.gov (United States)

    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.

  13. Be-7 concentration in garden and wild vegetables in Japan

    International Nuclear Information System (INIS)

    Nobuhiko Ito; Iwao Kunugijama; Yoshinori Furukawa.

    1996-01-01

    Beryllium-7 is a natural radionuclide produced by cosmic rays. Be-7 is found vividly in the atmosphere, so the concentrations in airborne particles were analyzed by many investigators. It is known that airborne particles with Be-7 in the atmosphere fall slowly to the ground and adhere to plant surface. However, Be-7 concentrations of foods were not measured too much. So we measured Be-7 concentrations of garden vegetables, wild vegetables, grasses, beef and milk, and calculated internal exposure dose from Be-7. Beryllium-7 concentrations of plant samples are shown. Beryllium-7 concentrations of garden vegetables were from 0.2 to 25.3 Bq/kg, and concentrations of wild vegetables were from 0.8 to 23.5 Bq/kg. There is no difference in Be-7 concentrations between garden vegetables and wild vegetables. Leaf vegetables have almost higher concentration of Be-7. Though Matteuccia Struthiopteris and Pteridium aquilinum are ferns, their eatable stages are sprouts. The relationship between surface area and Be-7 concentration in some vegetable leaves gathered simultaneously at the same farm is shown. Beryllium-7 concentrations of leaves correlate significantly with the surface area/weight ratios. What high concentration vegetables have proportionately broad leaves suggests that atmospheric Be-7 particles adhere to surface of leaves. (author)

  14. European medicinal and edible plants associated with subacute and chronic toxicity part I: Plants with carcinogenic, teratogenic and endocrine-disrupting effects.

    Science.gov (United States)

    Kristanc, Luka; Kreft, Samo

    2016-06-01

    In recent decades, the use of herbal medicines and food products has been widely embraced in many developed countries. These products are generally highly accepted by consumers who often believe that "natural" equals "safe". This is, however, an oversimplification because several botanicals have been found to contain toxic compounds in concentrations harmful to human health. Acutely toxic plants are in most cases already recognised as dangerous as a result of their traditional use, but plants with subacute and chronic toxicity are difficult or even impossible to detect by traditional use or by clinical research studies. In this review, we systematically address major issues including the carcinogenicity, teratogenicity and endocrine-disrupting effects associated with the use of herbal preparations with a strong focus on plant species that either grow natively or are cultivated in Europe. The basic information regarding the molecular mechanisms of the individual subtypes of plant-induced non-acute toxicity is given, which is followed by a discussion of the pathophysiological and clinical characteristics. We describe the genotoxic and carcinogenic effects of alkenylbenzenes, pyrrolizidine alkaloids and bracken fern ptaquiloside, the teratogenicity issues regarding anthraquinone glycosides and specific alkaloids, and discuss the human health concerns regarding the phytoestrogens and licorice consumption in detail. Copyright © 2016 Elsevier Ltd. All rights reserved.

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

    Science.gov (United States)

    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.

  16. Effects of arsenic on nitrate metabolism in arsenic hyperaccumulating and non-hyperaccumulating ferns

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Nandita [Soil and Water Science Department, University of Florida, Gainesville, Fl 32611-0290 (United States); Eco-Auditing group, National Botanical Research Institute, Rana Pratap Marg, Lucknow 226 001 (India); Ma, Lena Q., E-mail: lqma@ufl.ed [Soil and Water Science Department, University of Florida, Gainesville, Fl 32611-0290 (United States); Vu, Joseph C. [Chemistry Research Unit, CMAVE, USDA-ARS, Gainesville, FL 32608-1069 and Agronomy Department, University of Florida, Gainesville, FL 32611-0500 (United States); Raj, Anshita [Eco-Auditing group, National Botanical Research Institute, Rana Pratap Marg, Lucknow 226 001 (India)

    2009-08-15

    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 four-month old Pteris vittata (arsenic - hyperaccumulator) and Pteris ensiformis (non-arsenic--hyperaccumulator) plants. The arsenic treatments (0, 150, and 300 muM as sodium arsenate) in hydroponics had adverse effects on the root and frond dry weights, and this effect was more evident in P. ensiformis than in P. vittata. Nitrate reductase and nitrite reductase activities of arsenate-treated plants were reduced more in P. ensiformis than in P. vittata. This effect was accompanied by similar decreases in tissue NO{sub 3}{sup -} concentrations. Therefore, this decrease is interpreted as being indirect, i.e., the consequence of the reduced NO{sub 3}{sup -} uptake and translocation in the plants. The study shows the difference in the tolerance level of the two Pteris species with varying sensitivity to arsenic. - Arsenic reduced the activity of nitrate and nitrite reductase more in Pteris ensiformis than Pteris vittata.

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

    OpenAIRE

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

    1994-01-01

    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 (rbc...

  18. [New species, newly used names and new ranges of tree ferns (Filicales: Cyatheaceae) in the Neotropics].

    Science.gov (United States)

    Rojas-Alvarado, A F

    2001-06-01

    Two new species are described for the Neotropics, four species are newly accepted, and four species and one variety are reported. The new species are: Cyathea grayumii A. Rojas and C. panamensis A. Rojas. Cyathea alfonsiana L. D. Gómez, C. holdridgeana Nisman & L. D. Gómez, C. onusta H. Christ and C. squarrosa (Rosenst.) Domin are recognized; Cnemidaria coclena Stolze, Cyathea andina (H. Karst.) Domin, C. caracasana var. meridensis (H. Karst.) R. M. Tryon, C. macrosora (Baker) Domin and C. pseudonanna (L. D. Gómez) Lellinger are reported from Costa Rica and Panama.

  19. Endosulfan induced changes in growth rate, pigment composition and photosynthetic activity of mosquito fern Azolla microphylla

    Directory of Open Access Journals (Sweden)

    Raja W.

    2012-11-01

    Full Text Available This paper is the first in a series reporting a study on the effects of different concentrations of insecticide, Endosulfan (0-600ppm was premeditated on 5th day after insecticide exposure with respect to growth rate, pigment composition and photosynthetic activity of Azolla microphylla under laboratory conditions which become non-target organism in the rice fields. Endosulfan inhibited the relative growth rate, pigment content and photosynthetic O2 evolution. Phycocyanin was main target followed by carotenoid and total chlorophyll. Significant increase in pigment, flavonoid and Anthocyanin was noticed after six days of treatment. In contrast to the photosynthetic activity, the rate of respiration in Azolla microphylla was increased significantly. Our results show that Endosulfan at normally recommended field rates and intervals are seldom deleterious to the beneficial and Eco friendly Azolla microphylla and their activities and thus in turn suppress plant growth and development. Phytotoxity of Azolla microphylla can be minimized by restrictions on application, timing, method and rate of application.

  20. Ferns and flowering plants of Klaserie Private Nature Reserve, eastern Transvaal: an annotated checklist

    Directory of Open Access Journals (Sweden)

    N. Zambatis

    1994-10-01

    Full Text Available An annotated checklist of the plant taxa of the Klaserie Private Nature Reserve, eastern Transvaal Lowveld, is presented. Of the 618 infrageneric taxa recorded, six are pteridophytes and the remainder angiosperms. Of these, 161 are monocotyledons and 451 dicotyledons. Five of the latter are currently listed in the Red Data List of the Transvaal, two of which are first records for the Transvaal Lowveld. The vegetation of the reserve shows strong affinities with the Savanna Biome, and to a lesser degree, with the Grassland Biome.

  1. Gene Flow among Populations of Two Rare Co-Occurring Fern Species Differing in Ploidy Level

    Czech Academy of Sciences Publication Activity Database

    Bucharová, Anna; Münzbergová, Zuzana

    2012-01-01

    Roč. 7, č. 9 (2012), e45855 E-ISSN 1932-6203 R&D Projects: GA MŠk 2B06178; GA ČR GA526/09/0549 Institutional support: RVO:67985939 Keywords : genetic variation * tetraploid species * diploid species Subject RIV: EF - Botanics Impact factor: 3.730, year: 2012

  2. Phytoremediation of petroleum hydrocarbons by using a freshwater fern species Azolla filiculoides Lam.

    Science.gov (United States)

    Kösesakal, Taylan; Ünal, Muammer; Kulen, Oktay; Memon, Abdülrezzak; Yüksel, Bayram

    2016-01-01

    In this study, the phytoremediation capacity of Azolla filiculoides Lam. for the water resources contaminated with petroleum hydrocarbons was investigated. The plants were grown in nitrogen-free Hoagland nutrient solution containing 0.005%, 0.01%, 0.05%, 0.1%, 0.2%, 0.3%, 0.4%, and 0.5% crude oil under greenhouse conditions for 15 days. Although the growth rate of the plants were not negatively influenced by the presence of crude oil in the media for the concentration of 0.005% and 0.01% v/v, a gradual impeding effect of crude oil in the growth media has been observed at concentrations 0.05-0.1%. More than 0.1% crude oil in the growth medium ostensibly retarded the growth. For example, 0.2% oil in the media reduced growth approximately 50% relative to the control, and the presence of crude oil at concentrations 0.3% or more were lethal. The data about the percentage of plant growth, fresh weight increase and root growth clearly indicated that the tolerance level of A. filiculoides plants to crude oil ranges between 0.1% and 0.2%. In comparison to control samples, the biodegradation rate of total aliphatic and aromatic (phenathrene) hydrocarbons at 0.05-0.2% oil concentrations, was 94-73% and 81-77%, respectively. On the other hand, in case of further increases in oil concentration in media, i.e.; 0.3-0.5%, the biodegradation rate was still higher in the experimental samples, respectively 71-63% and 75-71%. The high biodegradation rates of petroleum hydrocarbons in the experimental samples suggested that A. filiculoides plants could be a promising candidate to be used for the phytoremediation of low crude oil contaminated precious freshwater resources.

  3. Medicina, exilio y suicidio Carlos Díez Fernández (1903-1952)

    OpenAIRE

    Rojo Vega, Anastasio

    2009-01-01

    Producción Científica Aquella mañana de Noviembre de 1921, la ciudad de Valladolid amaneció envuelta en brumas y cubierta de escarcha. El Pisuerga le prodigaba sus caricias de frío y niebla. Los habitantes la cruzaban rápidos, envueltos en sus abrigos y bufandas, camino de la oficina, del taller o de la Universidad, sin detenerse a contemplar escaparates ni a saludar a sus amigos. En el Instituto Anatómico Sierra, de la Facultad de Medicina, los estudiantes que iban ll...

  4. Flores, Fernández y Oliva: tres azulejeros para las obras reales de Felipe II

    Directory of Open Access Journals (Sweden)

    Pleguezuelo, Alfonso

    2002-06-01

    Full Text Available Que las obras de arquitectura promocionadas por Felipe II eran acabadas frecuentemente con revestimientos de azulejos es una idea conocida desde hace tiempo. El ejemplo más frecuentemente aducido es el de los aposentos del mismo rey en el Monasterio de San Lorenzo de El Escorial aunque podrían ser citados muchos más casos conservados y otros conocidos a través de la documentación. Este rasgo de la arquitectura filipina y el personal interés del rey por el asunto debió ser un importante acicate para el desarrollo de la azulejería española en la segunda mitad del siglo XVI. Tres artistas han sido citados desde hace años como autores de los azulejos para Felipe II. Por un lado, el flamenco Juan Flores, del que tan sólo se tenían unas pocas noticias literarias sobre su vida y su obra y que recientemente he tenido la oportunidad de revisar a luz de nuevos documentos y obras.…

  5. L-Myo-inositol 1-phosphate synthase in the aquatic fern Azolla filiculoides.

    Science.gov (United States)

    Benaroya, Rony Oren; Zamski, Eli; Tel-Or, Elisha

    2004-02-01

    L-Myo-inositol 1-phosphate synthase (INPS EC 5.5.1.4) catalyzes the conversion of D-glucose 6-phosphate to L-myo-inositol 1-phosphate. INPS is a key enzyme involved in the biosynthesis of phytate which is a common form of stored phosphates in higher plants. The present study monitored the increase of INPS expression in Azolla filiculoides resulting from exposure to inorganic phosphates, metals and salt stress. The expression of INPS was significantly higher in Azolla plants that were grown in rich mineral growth medium than those maintained on nutritional growth medium. The expression of INPS protein and corresponding mRNA increased in plants cultured in minimal nutritional growth medium when phosphate or Zn2+, Cd2+ and NaCl were added to the growth medium. When employing rich mineral growth medium, INPS protein content increased with the addition of Zn2+, but decreased in the presence of Cd2+ and NaCl. These results indicated that accumulation of phytate in Azolla is a result of the intensified expression of INPS protein and mRNA, and its regulation may be primarily derived by the uptake of inorganic phosphate, and Zn2+, Cd2+ or NaCl.

  6. Ontogenetic characterization of sporangium and spore of Huperzia serrata: an anti-aging disease fern.

    Science.gov (United States)

    Long, Hua; Li, Jing; Li, You-You; Xie, De-Yu; Peng, Qing-Zhong; Li, Li

    2016-12-01

    Huperzia serrata is a medicinal plant used in Traditional Chinese Medicine, which has been used to prevent against aging diseases. It is mainly propagated by spores and grows extremely slowly. Due to severe harvest, it is a highly endangered species. In this report, we characterize ontogenesis of sporangia and spores that are associated with propagation. A wild population of H. serrata plants is localized in western Hunan province, China and protected by Chinese Government to study its development (e.g. sporangia and spores) and ecology. Both field and microscopic observations were conducted for a few of years. The development of sporangia from their initiation to maturation took nearly 1 year. Microscopic observations showed that the sporangial walls were developed from epidermal cells via initiation, cell division, and maturation. The structure of the mature sporangial wall is composed of one layer of epidermis, two middle layers of cells, and one layer of tapetum. Therefore, the sporangium is the eusporangium type. Spore development is characterized into six stages, initiation from epidermal cell and formation of sporogenous cells, primary sporogenous cell, secondary sporogenous cell, spore mother cell, tetrad, and maturation. The sporangial development of H. serrata belongs to the eusporangium type. The development takes approximately 1 year period from the initiation to the maturation. These data are useful for improving propagation of this medicinal plant in the future.

  7. Evidence for radiations of cheilanthoid ferns in the Greater Cape Floristic Region

    DEFF Research Database (Denmark)

    Eiserhardt, Wolf L.; Rohwer, Jens G.; Russell, Stephen J.

    2011-01-01

    The Greater Cape Floristic Region (GCFR) of southern Africa is characterised by large, endemic radiations of flowering plants, the so-called ‘Cape Clades’, but it is unknown whether such radiations are also found in non-angiosperms. We hypothesise that GCFR-endemic lineages exist in the xeric...

  8. Population Study of the Golden Chicken Fern (Cibotium barometz (L. J. Sm. in Riau Province, Sumatra

    Directory of Open Access Journals (Sweden)

    Titien Ngatinem Praptosuwiryo

    2017-05-01

    Full Text Available Cibotium barometz (L. J.Sm. (Cibotiaceae is an important export commodity for both traditional and mod-ern medicine. Populations of this species in several countries have decreased rapidly due to the uncontrolled collection of the rhizome parts for medicinal purposes. Since 1976, this species has been included in Appendix II of the Convention on International Trade in Endangered Species (CITES. This means that no export is allowed without a prior permit issued by the CITES committee.  In order to utilize an endangered species sustainably, the global NDF (Non-Detriments Finding system is applied for determining annual quotas. Therefore, monitoring and updating the inventory of C. barometz in its natural habitat should be carried out annually. A population study of C. barometz carried out in 2011 in Riau Province, Sumatra, is reported here. The aims of the study were: 1 to inventory C. barometz and determine its variation in Riau Province, Suma-tra, 2 to study the distribution and ecology of C. barometz, and 3 to assess the population size of this spe-cies by using random search methodology incorporating belt line transects. Two variants of C. barometz are recognized; they are the golden yellow and golden brown variants. C. barometz is distributed in eight loca-tions of Kampar District of Riau Province, in the secondary forest and rubber agroforest between 80 m and 600 m above sea level (asl. This species grows well in open to partially opened areas of secondary forest and rubber plantation in hills with a range of slope between 30° and 90°, with a relatively high humidity, 60 – 90%, in acid to nearly neutral soil, with a range of soil fertility from very poor to very humus rich soil.  The average population density determined in our study was 20 plants per 100 square meter. The highest popula-tion size was in the secondary forest of Bukit Kuda Beban at 590 – 600 m asl., viz. 9405 plants with a popula-tion density  of 47 plants per 100 square meter.

  9. The Tree-Ferns of the genus Cyathea in Australasia and the Pacific

    NARCIS (Netherlands)

    Hollttum, R.E.

    1964-01-01

    The present account of this genus follows the lines of that adopted for Flora Malesiana (ser. 11, 1, part 2, 1963). While studying Malesian species, I examined the types of those in neighbouring regions, to discover to what extent Malesian species were distributed further to the East and South-east.

  10. Functional groups of fossil marattialeans: chemotaxonomic implications for Pennsylvanian tree ferns and pteridophylls

    Czech Academy of Sciences Publication Activity Database

    Pšenička, J.; Zodrow, E. L.; Mastalerz, M.; Bek, Jiří

    2005-01-01

    Roč. 61, 3-4 (2005), s. 259-280 ISSN 0166-5162 R&D Projects: GA AV ČR(CZ) IAA3013902 Institutional research plan: CEZ:AV0Z30130516 Keywords : interdisciplinary approach * functional groups * FTIR Subject RIV: DB - Geology ; Mineralogy Impact factor: 1.397, year: 2005

  11. Measuring air layer volumes retained by submerged floating-ferns Salvinia and biomimetic superhydrophobic surfaces

    Directory of Open Access Journals (Sweden)

    Matthias J. Mayser

    2014-06-01

    Full Text Available Some plants and animals feature superhydrophobic surfaces capable of retaining a layer of air when submerged under water. Long-term air retaining surfaces (Salvinia-effect are of high interest for biomimetic applications like drag reduction in ship coatings of up to 30%. Here we present a novel method for measuring air volumes and air loss under water. We recorded the buoyancy force of the air layer on leaf surfaces of four different Salvinia species and on one biomimetic surface using a highly sensitive custom made strain gauge force transducer setup. The volume of air held by a surface was quantified by comparing the buoyancy force of the specimen with and then without an air layer. Air volumes retained by the Salvinia-surfaces ranged between 0.15 and 1 L/m2 depending on differences in surface architecture. We verified the precision of the method by comparing the measured air volumes with theoretical volume calculations and could find a good agreement between both values. In this context we present techniques to calculate air volumes on surfaces with complex microstructures. The introduced method also allows to measure decrease or increase of air layers with high accuracy in real-time to understand dynamic processes.

  12. GAMETOPHYTES OF THE BIRD NEST FERN Asplenium nidus L. (ASPLENIACEAE FROM WEST KALIMANTAN

    Directory of Open Access Journals (Sweden)

    Titien Ng. Praptosuwiryo

    2010-01-01

    Full Text Available Gametofit Asplenium nidus L dari Kalimantan Barat diamati dengan mengecambahkan spora pada media campuran akar paku pohon dan arang sekam (1:1. Penelitian ini bertujuan untuk mendapatkan bukti taksonomi baru untuk mendukung keberadaan jenis komplek dalam A. nidus. Spora coklat tua simetris bilateral yang berkecambah menghasilkan benang berklorofil yang terdiri atas 4-6 sel. Rizoid berkecambah pada sisi polar, sedangkan benang berklorofil pada sisi ekuator. Pembentukan piringan berawal pada sel sub terminal dari benang yang berkecambah pada hari ke-12 dengan pembelahan sel secara mencong. Rizoid terbentuk lagi pada sel-sel pangkal atau semi pangkal pada piringan. Gametofit muda berbentuk jantung panjang dan anteridium muda mulai timbul pada umur 60 hari. Gametofit dewasa menjantung dan menghasilkan anteridium dewasa mulai umur 75 hari. Gametofit hermaprodit dan betina tidak ditemukan. Sporofit muda mulai muncul pada umur 90 hari. Hasil penelitian menunjukkan bahwa ciri-ciri morfologi gametofit menambah bukti taksonomi dalam mendukung keberadaan jenis komplek atau jenis tersembunyi dalam A. nidus.

  13. Fern- und Fehlzündungen. Bedenken zu Ingeborg Bachmanns Wittgenstein-Rezeption / Georg Gimpl

    Index Scriptorium Estoniae

    Gimpl, Georg, 1949-

    2007-01-01

    Ettekanne Ingeborg Bachmanni 80. sünniaastapäevaks pühendatud rahvusvaheliselt konverentsilt Tartus 12.-13. aprillil 2006. aastal. Wittgensteini retseptsioonist Bachmanni loomingust Ludwig Wittgensteini "Loogilis-filosoofilise traktaadi" põhjal (Tartu : Ilmamaa, 1996)

  14. A fortuitous ant-fern association in the Amazon lowlands of Peru

    Directory of Open Access Journals (Sweden)

    Blanca León

    2011-05-01

    Full Text Available Myrmecophyly is best documented among tropical epiphytes, and myrmecotrophy occurs especially among domatia-forming plants. We report the case of Polytaenium cajenense with "external" domatia and its use by the same symbiont ant as its host Cordia nodosa. This case is interpreted as the result of stochastic events and their relations to pre-existing adaptations of all species involved.

  15. Diversity and distribution patterns of ferns and lycophytes in a cloud forest in Mexico

    Directory of Open Access Journals (Sweden)

    Arturo Sánchez-González

    2016-01-01

    Full Text Available La relación de la riqueza, diversidad y distribución de especies de helechos y licopodios con algunas variables climáticas y edáficas se analizó en el bosque mesófilo de montaña del municipio de Tlanchinol, Hidalgo. Se establecieron 24 parcelas de muestreo de 400 m 2 cada una, en tres pisos altitudinales situados entre 1,107 y 1,903 m. La diversidad alfa y beta, y el valor de importancia relativa (VIR de las especies se estimaron en cada parcela. La relación entre la riqueza, diversidad, VIR y las variables ambientales se estableció mediante análisis de redundancia, regresión lineal y árboles de regresión. Pocas especies presentaron VIR altos por parcela; los valores de riqueza y diversidad no mostraron diferencias estadísticamente significativas ( P < 0.05 con respecto a la altitud, pero s í con la temperatura mínima del mes más frío, precipitación del trimestre más cálido, orientación y pendiente. La diversidad beta incrementó con la altitud; esta diversidad fue baja entre pisos cercanos y alta en los extremos del gradiente. La distribución de las especies se relacion ó positivamente con la materia orgánica, isotermalidad y contenido de sodio; y negativamente con la precipitación del mes más seco, evapotranspiración real anual y evapotranspiración real en la temporada de lluvias.

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

    Science.gov (United States)

    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 (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

  17. Features of secondary birch young stands in low mountain Pokuttya (Ukrainian Carpathian mts.

    Directory of Open Access Journals (Sweden)

    S. Y. Milevskaya

    2015-06-01

    Full Text Available Forest landscapes of the region during the last 3–5 centuries undergone the profound anthropogenic transformation. Secondary young stands occupy 25% of the total forest area. The problem of derivatives is particularly relevant for the modern forest typology in the Carpathian region. It requires the reflection in its dynamic trends shaping the stands, especially mixed young stands. The aim of our study consisted in getting the knowledge of the structural features of the secondary phytocoenosis of birch young stands in this area.The object of the study was age class I saplings growing in the mountainous part of Pokuttya, particularly in the basin of the Lutshka River. The conceptual basis of our study is the modern dynamic vision that every forest type is a consecutive series of forest plant communities within each type of homogeneous growing conditions. We apply methods of ecological-floristic research of the Brown-Blanke school in the interpretation of the Polish school phytosociology. However we also take into account both syntaxonomy generalizations of the Ukrainian scientists. The actual material comprises the original geobotanical studies with fixation of the vast majority of species in plant communities. Mainly the species having diagnostic value to separate syntaxons were taken into account in the analytical processing. Young forest stands (with the height of 8–12 m and crown cover of 70% together form the trees Betula pendula and B. pubescens. Fairly numerous admixture is formed by trees Alnus incana; besides, there are Fagus sylvatica, Populus tremula, Quercus robur, Padus avium. For dominants, they can be called “grey-alder birch blackberry sedge bracken fern” – Betula pendula+Alnus incana–Rubus caesius–Carex brizoides+Pteridium aquilinum. It is rich in floristic composition of the plant communities. They contain at least 12 species of trees, 3 species of shrubs, 4 species of bushes and 89 species of herbs. Diagnostic

  18. Comparative genomic mapping of the bovine Fragile Histidine Triad (FHIT tumour suppressor gene: characterization of a 2 Mb BAC contig covering the locus, complete annotation of the gene, analysis of cDNA and of physiological expression profiles

    Directory of Open Access Journals (Sweden)

    Boussaha Mekki

    2006-05-01

    Full Text Available Abstract Background The Fragile Histidine Triad gene (FHIT is an oncosuppressor implicated in many human cancers, including vesical tumors. FHIT is frequently hit by deletions caused by fragility at FRA3B, the most active of human common fragile sites, where FHIT lays. Vesical tumors affect also cattle, including animals grazing in the wild on bracken fern; compounds released by the fern are known to induce chromosome fragility and may trigger cancer with the interplay of latent Papilloma virus. Results The bovine FHIT was characterized by assembling a contig of 78 BACs. Sequence tags were designed on human exons and introns and used directly to select bovine BACs, or compared with sequence data in the bovine genome database or in the trace archive of the bovine genome sequencing project, and adapted before use. FHIT is split in ten exons like in man, with exons 5 to 9 coding for a 149 amino acids protein. VISTA global alignments between bovine genomic contigs retrieved from the bovine genome database and the human FHIT region were performed. Conservation was extremely high over a 2 Mb region spanning the whole FHIT locus, including the size of introns. Thus, the bovine FHIT covers about 1.6 Mb compared to 1.5 Mb in man. Expression was analyzed by RT-PCR and Northern blot, and was found to be ubiquitous. Four cDNA isoforms were isolated and sequenced, that originate from an alternative usage of three variants of exon 4, revealing a size very close to the major human FHIT cDNAs. Conclusion A comparative genomic approach allowed to assemble a contig of 78 BACs and to completely annotate a 1.6 Mb region spanning the bovine FHIT gene. The findings confirmed the very high level of conservation between human and bovine genomes and the importance of comparative mapping to speed the annotation process of the recently sequenced bovine genome. The detailed knowledge of the genomic FHIT region will allow to study the role of FHIT in bovine cancerogenesis

  19. Comparative genomic mapping of the bovine Fragile Histidine Triad (FHIT) tumour suppressor gene: characterization of a 2 Mb BAC contig covering the locus, complete annotation of the gene, analysis of cDNA and of physiological expression profiles.

    Science.gov (United States)

    Uboldi, Cristina; Guidi, Elena; Roperto, Sante; Russo, Valeria; Roperto, Franco; Di Meo, Giulia Pia; Iannuzzi, Leopoldo; Floriot, Sandrine; Boussaha, Mekki; Eggen, André; Ferretti, Luca

    2006-05-23

    The Fragile Histidine Triad gene (FHIT) is an oncosuppressor implicated in many human cancers, including vesical tumors. FHIT is frequently hit by deletions caused by fragility at FRA3B, the most active of human common fragile sites, where FHIT lays. Vesical tumors affect also cattle, including animals grazing in the wild on bracken fern; compounds released by the fern are known to induce chromosome fragility and may trigger cancer with the interplay of latent Papilloma virus. The bovine FHIT was characterized by assembling a contig of 78 BACs. Sequence tags were designed on human exons and introns and used directly to select bovine BACs, or compared with sequence data in the bovine genome database or in the trace archive of the bovine genome sequencing project, and adapted before use. FHIT is split in ten exons like in man, with exons 5 to 9 coding for a 149 amino acids protein. VISTA global alignments between bovine genomic contigs retrieved from the bovine genome database and the human FHIT region were performed. Conservation was extremely high over a 2 Mb region spanning the whole FHIT locus, including the size of introns. Thus, the bovine FHIT covers about 1.6 Mb compared to 1.5 Mb in man. Expression was analyzed by RT-PCR and Northern blot, and was found to be ubiquitous. Four cDNA isoforms were isolated and sequenced, that originate from an alternative usage of three variants of exon 4, revealing a size very close to the major human FHIT cDNAs. A comparative genomic approach allowed to assemble a contig of 78 BACs and to completely annotate a 1.6 Mb region spanning the bovine FHIT gene. The findings confirmed the very high level of conservation between human and bovine genomes and the importance of comparative mapping to speed the annotation process of the recently sequenced bovine genome. The detailed knowledge of the genomic FHIT region will allow to study the role of FHIT in bovine cancerogenesis, especially of vesical papillomavirus-associated cancers of

  20. Rainfall and streamflow from small tree-covered and fern-covered and burned watersheds in Hawaii

    Science.gov (United States)

    H. W. Anderson; P. D. Duffy; Teruo Yamamoto

    1966-01-01

    Streamflow from two 30-acre watersheds near Honolulu was studied by using principal components regression analysis. Models using data on monthly, storm, and peak discharges were tested against several variables expressing amount and intensity of rainfall, and against variables expressing antecedent rainfall. Explained variation ranged from 78 to 94 percent. The...

  1. Comparison of nutrient uptake and their release in fern and grass stands on deforested areas in the Beskydy Mts

    Czech Academy of Sciences Publication Activity Database

    Tůma, Ivan; Fiala, Karel; Holub, Petr

    2005-01-01

    Roč. 18, - (2005), s. 73-78. ISBN 80-7157-297-7 R&D Projects: GA ČR(CZ) GA206/94/0385; GA ČR(CZ) GA526/97/0170 Institutional research plan: CEZ:AV0Z60050516 Keywords : decomposition * plant biomass * soil features Subject RIV: EF - Botanics

  2. 76 FR 45649 - Notice of Final Federal Agency Actions on I-5: Fern Valley Interchange Project: Jackson County, OR

    Science.gov (United States)

    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...

  3. Diversity, composition and host-species relationships of epiphytic orchids and ferns in two forest in Nepal

    Czech Academy of Sciences Publication Activity Database

    Adhikari, Y. P.; Fischer, A.; Fischer, H. S.; Rokaya, Maan Bahadur; Bhattarai, P.; Gruppe, A.

    2017-01-01

    Roč. 14, č. 6 (2017), s. 1065-1075 ISSN 1672-6316 Grant - others:European Comission(XE) 212459 Program:FP7 Institutional support: RVO:67985939 Keywords : environmental factors * epiphytes * large trees * indicator species * multivariate and univariate analyses * permutations tests Subject RIV: EH - Ecology, Behaviour OBOR OECD: Ecology Impact factor: 1.016, year: 2016

  4. Diversity, composition and host-species relationships of epiphytic orchids and ferns in two forests in Nepal

    Czech Academy of Sciences Publication Activity Database

    Adhikari, Y. P.; Fischer, A.; Fischer, H. S.; Rokaya, Maan Bahadur; Bhattarai, P.; Gruppe, A.

    2017-01-01

    Roč. 14, č. 6 (2017), s. 1065-1075 ISSN 1672-6316 R&D Projects: GA ČR GB14-36098G Institutional support: RVO:86652079 Keywords : vascular epiphytes * kathmandu valley * managed forests * dry forest * land-use * richness * conservation * biodiversity * assemblages * preferences * Environmental factors * Epiphytes * Large trees * Indicator species * Multivariate and univariate analyses * Permutations tests Subject RIV: EF - Botanics OBOR OECD: Environmental sciences (social aspects to be 5.7) Impact factor: 1.016, year: 2016

  5. District heating systems - the necessary infrastructure for geothermal energy; Fern- und Nahwaermesysteme - notwendige Infrastruktur fuer die Geothermie

    Energy Technology Data Exchange (ETDEWEB)

    Schoenberg, I [Inst. fuer Umwelt-, Sicherheits- und Energietechnik e.V. (UMSICHT), Oberhausen (Germany)

    1997-12-01

    The contribution discusses the future chances of geothermal energy use with cost-optimized systems of geothermal energy + cogeneration + district heating and with the focus on innovation instead of state funding. (orig./AKF) [Deutsch] Der Beitrag bezieht sich auf die zukuenftigen Chancen der Geothermie, die eine kostenoptimierte Systemloesung Geothermie + KWK + Nah-/Fernwaerme sowie durch Mut zur Innovation und nicht durch Foerderung bestimmt werden. (orig./AKF)

  6. Phylogeny, historical biogeography and characters evolution of the drought resistant fern Pyrrosia Mirbel (Polypodiaceae) inferred from plastid and nuclear markers.

    Science.gov (United States)

    Wei, Xueping; Qi, Yaodong; Zhang, Xianchun; Luo, Li; Shang, Hui; Wei, Ran; Liu, Haitao; Zhang, Bengang

    2017-10-06

    Pyrrosia s.l. comprises ca. 60 species with a disjunct Africa/Asia and Australia distribution. The infrageneric classification of Pyrrosia s.l. is controversial based on the phylogenetic analyses of chloroplast markers and morphology. Based on the expanded taxon sampling of Pyrrosia s.l. (51 species), we investigated its phylogeny, biogeography, character evolution and environmental adaptation by employing five chloroplastid markers (rbcL, matK, psbA-trnH, and rps4 + rps4-trnS) and one single (low)-copy nuclear gene, LEAFY. Pyrrosia s.l. was divided into six major clades and eight subclades. Reticulate evolution was revealed both among clades and among species in Pyrrosia s.l. Ancestral character state optimization revealed high levels of homoplastic evolution of the diagnostic characters in Pyrrosia s.l., while the crassulacean acid metabolism pathway seems to have an independent origin. Molecular dating and biogeographic diversification analyses suggested that Pyrrosia s.l. originated no later than the Oligocene and the main clades diversified during the Oligocene and Miocene, with southern Asia, the Indo-China Peninsula and southwestern and southern China as the most likely ancestral areas. Transoceanic long-distance dispersal, rather than vicariance, contributed to the intercontinental disjunction. Diversification scenarios of Pyrrosia s.l. under geological movements and climate fluctuation are also discussed.

  7. Procedimientos constructivos en el "Museo de la Novela de la Eterna", de Macedonio Fernández

    Directory of Open Access Journals (Sweden)

    Fabiola Orquera

    2016-04-01

    Full Text Available La idea de este trabajo es que el rechazo a la poética realista, premisa que funda Museo de la Novela de la Eterna, rige su escritura a nivel de su enunciación y su enunciado, de las instancias del autor y del lector y del espacio que ocupa en el corpus literario. Para comprobar tal afirmación se considerarán los principios constructivos de este texto, impregnados de la estética surrealista, pero novedosos en cuanto se expresan en prosa narrativa. A partir de ellos se intentará identificar los recursos alternativos que organizan la escritura, inspirados en el deseo de mostrar el trabajo productivo de toda "obra" literaria, mediante la deconstrucción (en el sentido literal de lo verosímil. En base a estas consideraciones, se establecerán relaciones entre la novela y líneas teóricas (literarias actuales. The idea of this work is that the rejection of realistic poetic, which is the premise of Museo de la Novela de la Eterna, guides its writing at the level of the narrative voice and the narration, of the author's and reader's degrees and of its place in literature. The text's constructive principles are studied, which are steeped in the surrealistic aesthetic, but they are new since they are expressed in narrative prose. The alternative resources that organize the writing are identified, inspired by the desire to show the "productive work" of all literary "work", through the deconstruction (in the literal sense of the probable. Based on these considerations, relationships are established between this novel and current theoretical (literary lines.

  8. Test and evaluation of Fern Engineering Company, Incorporated, solar heating and hot water system. [structural design criteria and system effectiveness

    Science.gov (United States)

    1979-01-01

    Tests, test results, examination and evaluation by Underwriters Laboratory, Inc., of a single family solar heating and hot water system consisting of collector, storage, control, transport, and data acquisition are presented. The structural characteristics of the solar flat plate collectors were evaluated according to snow and wind loads indicated in various building codes to determine their suitability for use both Michigan and Pennsylvania where prototype systems were installed. The flame spread classification of the thermal insulation is discussed and the fire tests conducted on components are described. The operation and dielectrics withstand tests of the energy transport module indicate the module is capable of rated air delivery. Tests of the control panel indicate the relay coil temperatures exceed the temperature limits allowed for the insulating materials involved.

  9. Structure and Development of the Gametophytes of Philippine Cheilanthoid Ferns, III. Cheilanthes concolor (Langsdorff et Fischer R. Tryon

    Directory of Open Access Journals (Sweden)

    Prescillano Zamora

    1993-12-01

    Full Text Available The gametophytes of Cheilanthes concolor (Langsdorff et Fischer R. Tryon from the Philippines (Quezon City are no different in pattern of development and in morphology from those from India with one possible notable difference, which is, that the gametophytes under report (which were grown from spores produced from 32-sporate sporangia are apogamous while those from India (sporangial type of source was not stated are sexual.

  10. Variability in the germination of spores among and within natural populations of the endangered tree fern Dicksonia sellowiana Hook. (Xaxim

    Directory of Open Access Journals (Sweden)

    Gabriela Schmitz Gomes

    2006-01-01

    Full Text Available The objective of this study was to analyze the existing variability in the germination of individuals' spores collected from two natural populations of Dicksonia sellowiana in southern Brazil. The largest intrapopulational variation was observed for the spores germination. These results suggested the existence of adaptative strategies that favored the gradual and continuous entrance of new individuals into the gametophytic population. The behavior of the individuals of the species within each population followed a similar pattern of initial development, in spite of conspicuous differences in the population structure. This showed a low differentiation between the populations and the existence of adaptative strategies which were common to both communities.O Xaxim (Dicksonia sellowiana Hook. (Dicksoniaceae é uma samambaia arborescente que se encontra principalmente sob o domínio da Floresta Ombrófila Mista. A exploração intensiva de seus indivíduos para retirada do caule, empregado na fabricação de vasos e substrato para o cultivo de plantas ornamentais, e a crescente antropização das áreas florestadas, tem degradado suas populações naturais. Este estudo teve como objetivo analisar a variabilidade existente na germinação de esporos de Xaxim. Os esporos foram coletados das frondes de indivíduos de Xaxim procedentes de duas populações naturais do Sul do Brasil. Foi observada uma maior variação intrapopulacional para a germinação e porcentagem de esporos inviáveis. Estes resultados sugerem a existência de estratégias adaptativas que favorecem a entrada gradual e contínua de novos indivíduos na população de gametófitos. O comportamento dos indivíduos da espécie dentro de cada população segue padrão semelhante de velocidade de desenvolvimento inicial, a despeito das diferenças conspícuas na estrutura populacional, sugerindo baixa diferenciação entre as populações e a existência de estratégias adaptativas comuns a ambas comunidades, para as características estudadas.

  11. Occurrence of nutrients and plant hormones (cytokinins and IAA) in the water fern Salvinia molesta during growth and composting

    Czech Academy of Sciences Publication Activity Database

    Arthur, G. D.; Stirk, W. A.; Novák, Ondřej; Hekera, P.; van Staden, J.

    2007-01-01

    Roč. 61, č. 2 (2007), s. 137-144 ISSN 0098-8472 R&D Projects: GA MŠk(CZ) LC06034; GA ČR GA206/05/0894 Institutional research plan: CEZ:AV0Z50380511 Source of funding: V - iné verejné zdroje ; V - iné verejné zdroje Keywords : auxins * culture medium * cytokinins Subject RIV: BO - Biophysics Impact factor: 1.810, year: 2007

  12. A systemic gene silencing method suitable for high throughput, reverse genetic analyses of gene function in fern gametophytes

    Directory of Open Access Journals (Sweden)

    Tanurdzic Milos

    2004-04-01

    Full Text Available Abstract Background Ceratopteris richardii is a useful experimental system for studying gametophyte development and sexual reproduction in plants. However, few tools for cloning mutant genes or disrupting gene function exist for this species. The feasibility of systemic gene silencing as a reverse genetics tool was examined in this study. Results Several DNA constructs targeting a Ceratopteris protoporphyrin IX magnesium chelatase (CrChlI gene that is required for chlorophyll biosynthesis were each introduced into young gametophytes by biolistic delivery. Their transient expression in individual cells resulted in a colorless cell phenotype that affected most cells of the mature gametophyte, including the meristem and gametangia. The colorless phenotype was associated with a 7-fold decrease in the abundance of the endogenous transcript. While a construct designed to promote the transient expression of a CrChlI double stranded, potentially hairpin-forming RNA was found to be the most efficient in systemically silencing the endogenous gene, a plasmid containing the CrChlI cDNA insert alone was sufficient to induce silencing. Bombarded, colorless hermaphroditic gametophytes produced colorless embryos following self-fertilization, demonstrating that the silencing signal could be transmitted through gametogenesis and fertilization. Bombardment of young gametophytes with constructs targeting the Ceratopteris filamentous temperature sensitive (CrFtsZ and uroporphyrin dehydrogenase (CrUrod genes also produced the expected mutant phenotypes. Conclusion A method that induces the systemic silencing of target genes in the Ceratopteris gametophyte is described. It provides a simple, inexpensive and rapid means to test the functions of genes involved in gametophyte development, especially those involved in cellular processes common to all plants.

  13. Changes in abiotic influences on seed plants and ferns during 18 years of primary succession on Puerto Rican landslides

    Science.gov (United States)

    Lawrence R. Walker; Aaron B. Shiels; Peter J. Bellingham; Ashley D. Sparrow; Ned Fetcher; Fred H. Landau; Deborah J. Lodge

    2013-01-01

    Abiotic variables are critical drivers of succession in most primary seres, but how their influence on biota changes over time is rarely examined. Landslides provide good model systems for examining abiotic influences because they are spatially and temporally heterogeneous habitats with distinct abiotic and biotic gradients and post-landslide erosion. In an 18-year...

  14. Warnings to the far future. Radioactive wastes as a communications problem. Warnungen an die ferne Zukunft. Atommuell als Kommunikationsproblem

    Energy Technology Data Exchange (ETDEWEB)

    Posner, R. (Technische Univ. Berlin (Germany, F.R.). Arbeitsstelle fuer Semiotik) (ed.)

    1990-01-01

    Inquiries were launched in the USA, in Poland, France, Hungary, Brazil, and the Federal Republic of Gemany to find semiotic solutions to problems arising from the communication of radioactive waste locations and dangers to posteriority. How can information be communicated over a period of 10000 years What has been communicated to us from the past 10000 years It seems to be sure that neither natural nor artificial barriers nor remnants (e.g. skeletons) or sources (today's communication), but only explicit messages will keep intelligent creatures from intrusion into radioactive waste depositories. Among the subjects dealt with are: Pandora's box and how to prevent its opening; mathematical coding on living sign matter; living detectors and complementary signs: ray coat, broken eye, and nuclear sirens; the three-chamber system: a way to the democratic organization of collective knowledge and conscience which can survive millennia. (orig./HSCH).

  15. Compatibility of entomopathogenic fungi with extracts of plants and ...

    African Journals Online (AJOL)

    The compatibility of some commercial botanicals (Biospark, Phytophrate, Exodos, Biodos and Neemgold) and of solvent extracts of Syndrella nodiflora, Premna tomentosa, Vitex negundo, Ipomea carnea, Pteridium aquilinum (leaves) and Annona squomosa (seeds) with Beauveria bassiana (Bals.) Vuil., Isaria ...

  16. Differences on post-fire regeneration of the pioneer trees Cecropia glazioui and Trema micrantha in a lowland Brazilian Atlantic Forest

    Directory of Open Access Journals (Sweden)

    Dalva M Silva-Matos

    2005-06-01

    Full Text Available A study of natural post-fire succession was carried out in a disturbed vegetation around fragments of the Atlantic Rain Forest (National Biological Reserve of Poço das Antas (22 °30 ’-22 °33 ’S,42 °15 ’-42 °19 ’W, Rio de Janeiro State.All the pre-fire individuals of Cecropia and Trema in the area were numbered with plastic labels.In order to check for the presence of new sprouts and mortality,two other censuses were carried out,at 3 and 12 months after the fire.The dominant species were:Pteridium aquilinum,Panicum maximum,Trema micrantha and Cecropia glazioui. Few days after the passage of fire, grasses and ferns spread their area,while the stands of Trema and Cecropia were completely burned. Most of individuals of Cecropia produced some sprouts while most of individuals of Trema died.However,a great number of seedlings of Trema were recruited while only one single seedling of Cecropia were observed during a period of one year.Most of these seedlings died through the year while the sprouts were already reproducing.The uses of Cecropia in places where fire is recurrent could be more appropriate because of its higher chance of survival and faster recovering ability after fire.Rev.Biol.Trop.53(1-2:1-4.Epub 2005 Jun 24Se realizó un estudio sobre la sucesión natural después del fuego en una vegetación alrededor de fragmentos de la selva lluviosa atlántica (Reserva Biológica Nacional de Poço das Antas (22° 30 ’-22° 33 ’ S, 42° 15’- 42° 19’ W, Estado de Río de Janeiro.Todos los individuos de Cecropia y Trema previos del fuego en el área fueron numerados con marcas plásticas. Se realizaron otros dos censos, 3 y 12 meses después del fuego con el objetivo de detectar mortalidad y buscar la presencia de nuevos brotes. Las especies dominantes fueron: Pteridium aquilinum, Panicum maximum, Trema micrantha y Cecropia glazioui. Pocos días después del paso del fuego,los pastos y helechos se dispersaron por el área, mientras

  17. Hot and cold executive functions in pure opioid users undergoing ...

    African Journals Online (AJOL)

    2016-01-12

    Jan 12, 2016 ... use of rationality and logic, such as working memory (WM), cognitive flexibility, response ... For instance, Bracken compared short‑ and long‑term ..... Development of “hot” executive function: The children's gambling task.

  18. Examination of ecosystems affected by the Chernobyl reactor accident and assessment of resulting radiation exposure of the population

    International Nuclear Information System (INIS)

    Fielitz, U.

    2001-01-01

    Since 1988, within the scope of several research projects, in 7,000 samples of soil, plants, mushrooms and game from forest ecosystems, the 137 Cs activity concentration was measured, in order to investigate the dynamics of the nuclide. The investigation sites are a spruce mountain forest near the village Bodenmais (Bavaria) and an oak forest close to Fuhrberg (Lower Saxony). In both forests, unfavourable location conditions cause a relativ high transfer of 137 Cs into plants and game. Typifying for the 3 forest sites was the high intra- and interspecies variablilty of the 137 Cs activity concentration. Even 14 years after the Chernobyl-fallout at the 3 investigation sites, the average 137 Cs inventory, contained in the top 10 cm of soil was 56% and 93% in the top 20 cm. From 1987 till 1994, in the leaves of the investigated plant species the 137 Cs activity concentration decreased significant, during the following years there was little change. The effective half life of 137 Cs varies between -3 years for raspberry and -24 years for the fern Pteridium aquillinum, whereas most of the plant species show half lifes of about -5 years. In 2000, as usual mushrooms from the Bodenmais investigation site showed the highest 137 Cs contaminations. The aggregated transfer factors (T agg ) for soil → plant and soil → flesh varied with several orders of magnitude. T agg values for Soil → autotroph plant species reached from 0,0001 m 2 .kg -1 to 0,41 m 2 .kg -1 . While at the permanent study plots in Bodenmais and Fuhrberg the T agg values were of comparable quantity, at Goettingen, they were lower than two orders of magnitude. For example T agg for Cs-137 in wild boar from Bodenmais was 392 times higher than for wild boar from Goettingen. From 1987 till 2000, the 137 Cs activity in roe-deer from Bodenmais varied according to the seasons, with highest values in autumn, and lowest values in spring. In consequence of the decrease of the 137 Cs activity concentration in

  19. Examination of ecosystems affected by the Chernobyl reactor accident and assessment of resulting radiation exposure of the population

    International Nuclear Information System (INIS)

    Fielitz, U.

    1999-01-01

    This paper deals with investigations about the behaviour of radiocaesium, carried out in two selected forest ecosystems. In 1997 and 1998 samples from soil, plants, trees and roe deer from forest areas, located near Bodenmais (Bavaria) and Fuhrberg (Lower Saxony) were measured on the 137 Cs activity. In this areas intensive studies about the behaviour of radiocaesium were already carried out from 1987 until 1994, so that long term data are available. Investigations on vertical distribution of 137 Cs in soil were leaded through on permanent 100 x 100 m study plots. Even 11 years after the Chernobyl-fallout, the activity is highest in humic horizonts, only vestiges were found deeper than 20 cm in soil profile. The majority of total activity is still present in the upper 10 cm of soil. At the permant study plot B1 in Bodenmais in 1997 there were found about 78% of the 137 Cs activity concentration (100%=100830 Bq x m -2 ) in this layer, of what 27% were located in the 4 cm thick humic layer. Comparisons of the vertical distribution in 1998, 1992 and 1997 show, that the velocity of radiocesium migration takes down with time. From 1987 until 1998 the 137 Cs activity in leaves of different plant species decreased significant. The effective half life of 137 Cs varies between 5 years for raspberry (Rubus idaeus) and 33 years for fern (Pteridium aquillinum), whereby most of the plant species show half lifes of about 10 years. The 137 Cs activity-decline slowed down from 1994 until 1998. There were considerable differences in 137 Cs activity between various plant species. 1998 for example, the concentration of 137 Cs in samples, taken at the same time from the permanent study plot B1, ranged from 380 Bq x kg -1 (dry weight) in raspberry to 16800 Bq x kg -1 in fern (Dryopteris carthusiana). In muscle flesh of roe-deer of Bodenmais from 1987 until 1998 the 137 Cs activity varied according to the seasons, the highest values were found in autumn, the lowest values in spring. In

  20. Variation in ploidy level and phenology can result in large and unexpected differences in demography and climatic sensitivity between closely related ferns.

    NARCIS (Netherlands)

    Groot, de G.A.; Zuidema, P.A.; Groot, H.; During, H.J.

    2012-01-01

    • Premise of the study: Current environmental changes may affect the dynamics and viability of plant populations. This environmental sensitivity may differ between species of different ploidy level because polyploidization can influence life history traits. We compared the demography and climatic