94,546 research outputs found
Burmese amber fossils bridge the gap in the Cretaceous record of polypod ferns
No full textpublisher: Elsevier articletitle: Burmese amber fossils bridge the gap in the Cretaceous record of polypod ferns journaltitle: Perspectives in Plant Ecology, Evolution and Systematics articlelink: http://dx.doi.org/10.1016/j.ppees.2016.01.003 content_type: article copyright: Copyright © 2016 Elsevier GmbH. All rights reserved.Copyright © 2016 Elsevier GmbH. All rights reserved. This document is the authors' final accepted version of the journal article. You are advised to consult the publisher's version if you wish to cite from it.NHM Repositor
Distribution, habitat preferences and population sizes of two threatened tree ferns, Cyathea cunninghamii and Cyathea x marcescens, in south-eastern Australia
No full textThe distribution, population sizes and habitat preferences of the rare tree ferns Cyathea cunninghamii Hook.f. (Slender Tree Fern) and F1 hybrid Cyathea x marcescens N.A.Wakef. (Skirted Tree Fern) in south-eastern Australia are described, together with the extension of the known distribution range of Cyathea cunninghamii from eastern Victoria into south-eastern New South Wales. Floristic and ecological data, encompassing most of the known habitat types, vegetation associations and population sizes, were collected across 120 locations. Additional information was sought from literature reviews, herbarium collections and field surveys of extant populations.
Cyathea cunninghamii is widespread, with the majority of populations occurring in Tasmania and Victoria, one population in south-eastern NSW and a disjunct population in south-eastern Queensland; Cyathea x marcescens is confined to south and eastern Victoria and south and north eastern Tasmania. Both taxa occur on King Island in Bass Strait. Both taxa have a near coastal distribution with most populations occurring in sub-coastal hinterland and escarpment forests with a median altitude of 288 m. Hierarchical cluster analysis of floristic data across the species’ geographic range identified six vegetation communities ranging from rainforest to damp sclerophyll forest. Their micro-habitat preferences were consistently identified as steeply incised gullies of minor headwater streams of coastal and sub-coastal ranges with a plentiful moisture regime and geomorphic protection from extreme stream flow events, flooding and bank scouring. Sporophyte recruitment was associated with exposed soil of stream banks and edges of constructed walking tracks.
Population sizes of both taxa are small with the majority of populations consisting of less than five adult individuals, with total populations of Cyathea cunninghamii and Cyathea x marcescens estimated at 919 and 221 mature individuals respectively.
Population extinctions in Victoria and Tasmania have primarily been associated with outlier populations in regions subject to agricultural land clearance, habitat modification and changes to fire regimes in crown forests. Nonanthropogenic mortality was associated with land slips, tree falls and stream bank scouring by flood water. Conservation of the hybrid Cyathea x marcescens necessitates the preservation of habitats where both Cyathea cunninghamii and Cyathea australis occur in close proximity to substrates suitable for spore germination. In future, molecular techniques may prove useful for field identification of juvenile stages, facilitating selection of progeny of Cyathea cunninghamii and Cyathea x marcescens for cultivation and re-introduction to sites of previous or possible future extinctions
Combining Characters of Pteridaceae and Tree Ferns: Pterisorus Radiata gen. et sp. nov., A Permineralized Lower Cretaceous Filicalean with Radial Sori
No full textAn anatomically preserved leptosporangiate filicalean that combines characters of the Pteridaceae and tree ferns has been discovered in the Lower Cretaceous (Valanginian-Hauterivian boundary) Apple Bay flora on Vancouver Island, Canada. Exindusiate sori are radial, with numerous annulate sporangia diverging from a conical receptacle that is positioned below a pinnule vein. No paraphyses or other trichomes are present. Sporangia have a nearly vertical annulus that is not interrupted by the long, quadriseriate stalk. Spores are trilete and angular, with a distinctive equatorial flange and a distal deltoid structure that contacts the rim at the corners of the spore. The suture extends three-fourths of the distance to the margin and is flanked by prominent ridges. Spore walls consist of two dense layers, and the surface is psilate. Pterisorus radiata gen. et sp. nov. has characters that are reminiscent of both tree ferns and the most highly derived of modern species, providing direct evidence for the third major radiation of Filicales
Phylogeny and Evolution of Ferns (monilophytes) With a Focus on the Earlu Leptosporangiate Divergences
No full textThe phylogenetic structure of ferns (= monilophytes) is explored here, with a special focus on the early divergences among leptosporangiate lineages. Despite considerable progress in our understanding of fern relationships, a rigorous and comprehensive analysis of the early leptosporangiate divergences was lacking. Therefore, a data set was designed here to include critical taxa that were not included in earlier studies. More than 5000 bp from the plastid (rbcL, atpB, rps4) and the nuclear (18S rDNA) genomes were sequenced for 62 taxa. Phylogenetic analyses of these data (1) confirm that Osmundaceae are sister to the rest of the leptosporangiates, (2) resolve a diverse set of ferns formerly thought to be a subsequent grade as possibly monophyletic (((Dipteridaceae, Matoniaceae), Gleicheniaceae), Hymenophyllaceae), and (3) place schizaeoid ferns as sister to a large clade of “core leptosporangiates” that includes heterosporous ferns, tree ferns, and polypods. Divergence time estimates for ferns are reported from penalized likelihood analyses of our molecular data, with constraints from a reassessment of the fossil record
Estudos morfofisiológicos de duas samambaias epífitas da Mata Atlântica: Elaphoglossum luridum (Fée) Christ (Dryopteridaceae) e Vittaria lineata (l.) Smith (Pteridaceae)
No full textDissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Biológicas. Programa de Pós-Graduação em Biologia VegetalAs pteridófitas constituem um importante grupo de organismos da flora brasileira, muito dependentes das condições climáticas presentes na Floresta Atlântica. As epífitas são plantas que não possuem conexões diretas com o solo e utilizam-se de suporte, mas não dos nutrientes, dos forófitos em que se apoiam. Dentre a grande variedade de pteridófitas epífitas da Mata Atlântica, podemos citar as espécies Elaphoglossum luridum (Fée) H. Christ. (Dryopteridaceae) e Vittaria lineata (L.) Smith (Pteridaceae). Considerando-se o número reduzido de informações sobre a anatomia e a fisiologia de pteridófitas epífitas, foram realizadas as caracterizações anatômicas e estudos de diferentes aspectos da fisiologia, em ambas as espécies, através de análises de: conteúdo relativo de água (CRA), pigmentos fotossintéticos, fluorescência da clorofila a e a concentração de malato foliar, em plantas do grupo controle, submetidas ao estresse hídrico e à aplicação exógena de ácido abscísico (ABA); com o objetivo de observar caracteres importantes para a sobrevivência destas espécies em ambientes xéricos. Os materiais botânicos foram coletados na Unidade de Conservação Desterro - UFSC (UCAD), Florianópolis, SC, sendo cultivados na casa de vegetação do Departamento de Botânica - CCB - UFSC. Ambas as espécies estudadas apresentam características anatômicas relacionadas às condições xéricas, tais como: frondes coriáceas a cartáceas, que apresentam suculência, cutícula espessa, células epidérmicas com paredes periclinais espessas e estômatos, restritos a face abaxial. As análises fisiológicas demonstraram uma grande capacidade de manutenção hídrica em E. luridum e V. lineata, pois, mesmo em condições de estresse hídrico e aplicação de ABA exógeno, as espécies não apresentaram alterações significativas no CRA, mantendo altos níveis. Nas análises da concentração de pigmentos fotossintéticos, as plantas submetidas aos tratamentos de estresse demonstraram quedas significativas nos níveis de clorofila a e b, todavia as concentrações de carotenoides mantiveram-se estáveis. Os parâmetros fotossintéticos (?, Eoptimum e ETRmax), obtidos através das curvas rápidas de luz (RLC's), apresentaram quedas significativas após os tratamentos de estresse hídrico e aplicação de ABA. Em E. luridum, não foram encontradas evidências do metabolismo ácido das crassuláceas (CAM). Em V. lineata, plantas do grupo controle não apresentaram diferença no conteúdo de malato entre as amostras coletadas as 06h00min e as 18h00min, não demonstrando, assim, evidências do metabolismo CAM. Contudo, plantas submetidas ao estresse hídrico por sete dias e à aplicação exógena de ABA, apresentaram aumentos significativos nas concentrações de ?Malato, demonstrando uma acidificação noturna e revelando uma regulação positiva do metabolismo CAM. Assim, foram encontradas evidencias da possibilidade de alteração do modo de fixação de carbono da via C3 para o CAM, em resposta ao déficit hídrico e aplicação exógena de ABA, podendo, com isso, a espécie V. lineata apresentar o metabolismo CAM facultativo.Ferns are an important group of organisms of the flora, very dependent on climatic conditions present in the Atlantic Forest. Epiphytes are plants that do not have direct connections with the soil and utilize phorophytes just to support. Among the wide variety of epiphytic ferns of the Atlantic Forest, we can mention the species Elaphoglossum luridum (Fée) H. Christ. (Dryopteridaceae) and Vittaria lineata (L.) Smith (Pteridaceae). Considering the small number of information about the anatomy and physiology of epiphytic ferns, anatomical characterization and studies of different aspects of physiology in both species, were conduct through analysis of: relative water content (RWC), photosynthetic pigments, chlorophyll fluorescence, malate concentration of fronds. Three groups were analyzed: control group, group subjected to water stress and another subjected to exogenous application of abscisic acid (ABA), with the aim of observing important characters for the survival of these species in xeric environments. The botanical material was collected in the Environmental Desterro Park - UFSC (UCAD), Florianopólis, SC. The plants were kept in the greenhouse of the Botany Department - CCB - UFSC. Both species have anatomical features related to xeric conditions, such as coriaceous to chartaceous fronds that present succulence, presence of thick cuticle, epidermal cells with thick external periclinal walls and stomata restricted to the abaxial surface. The physiological analyzes showed a great ability to retain water in E. luridum and V. lineata, because even under conditions of water stress and exogenous abscisic acid (ABA) application, the species showed no significant changes in the RWC. In the analysis of the concentration of photosynthetic pigments, plants subjected to stress treatments showed significant decreases in levels of chlorophyll a and b, however the concentrations of carotenoids were kept stable. The photosynthetic parameters (á, Eoptimum and ETRmax), obtained by rapid light curves (RLC's), showed significant decreases after treatment of water stress and ABA application. In E. luridum, we did not found evidence of crassulacean acid metabolism (CAM). In V. lineata, the control group showed no difference in malate content of the samples collected between 06h00min and 18h00min, so there was no evidence of CAM metabolism. However, plants subjected to drought stress for seven days and the application of exogenous ABA showed significant increases in concentrations of ÄMalate, demonstrating a nocturnal acidification and revealing an up regulation of CAM metabolism. Thus, we found evidence of the possibility of changing the mode of carbon fixation pathway C3 to CAM in response to water stress and exogenous application of ABA and may, therefore, the species V. lineata present the facultative CAM metabolism
Estudo do potencial germinativo, do desenvolvimento gametofítico e do potencial de reprodução vegetativa de Gleichenella pectinata (Willd.) Ching (Pteridophyta - Gleicheniaceae)
No full textDissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Biológicas. Programa de Pós-Graduação em Biologia Vegetal.As pteridófitas representam um importante grupo vegetal da flora brasileira. Espécies são encontradas em diferentes regiões, desde cerrado, dunas, matas ou rochas. Algumas pteridófitas mostram-se pioneiras e eficientes na regeneração de fragmentos de floresta degradadas. Este trabalho tem a finalidade de estudar o potencial germinativo dos esporos e do desenvolvimento gametofítico de Gleichenella pectinata (Willd) Ching, o potencial de brotamento de rizomas e estacas caulinares, bem como analisar a morfo-anatomia dos gametófitos durante seu desenvolvimento e verificar o efeito de diferentes níveis de luz e temperatura no processo germinativo da espécie. As frondes férteis foram coletadas na Unidade de Conservação Ambiental Desterro (UCAD), Florianópolis-SC. Esporos foram separados dos esporângios por filtragem em papel entretela e armazenados a 7 1 oC. Observaram-se três padrões de desenvolvimento inicial gametofítico: clorócitos ricos em cloroplastos, gametófitos filamentosos com rizóide não desenvolvido e gametófitos com três a cinco células protaliais com rizóides desenvolvidos. Esporos foram esterilizados superficialmente em solução de hipoclorito de sódio comercial a 10% (v/v) durante 15 min, filtrados através de papel de filtro esterilizado e lavados diversas vezes com água destilada autoclavada. Foram semeados em frascos contendo 20 mL de meio mineral proposto por Mohr e modificado por Dyer, suplementado por Benomyl a 0,01%. Todos os procedimentos foram conduzidos em capela de fluxo laminar. Os testes de germinação foram realizados em sala de cultivo a 25 2 oC (30 mol m-2s-1), câmara de germinação a 30 2 oC (19 mol m-2s- 1) sob fotoperíodo de 16 horas, e diferentes níveis de luz (62, 42, 22 e 5% da luz natural). A germinação dos esporos iniciou-se após quatro dias de cultivo. Aos 14 dias os gametófitos eram formados por um ou mais clorócitos ricos em cloroplastos. Aos 21 dias os gametófitos possuíam de três a cinco células protonemais. Aos 34 dias alguns gametófitos permaneciam filamentosos e outros se apresentaram como um protalo laminar espatulado. Aos 48 dias os gametófitos tornaram-se cordiformes. Somente gametófitos com rizóides desenvolvidos atingiram a fase cordiforme. A maior porcentagem de gametófitos com rizóides, foi observada após 331 dias de armazenamento (18,16 ± 3,54%) para a coleta realizada em 06/11/2004 e a menor (1,53 ± 1,02 %) para a coleta realizada em 29/05/2004 cujos esporos foram armazenados por 49 dias. Não houve diferença estatisticamente significativa entre os resultados dos testes de germinação com e sem adição de Benlate ao meio mineral. O meio mineral solidificado com agar não foi mais eficiente que o meio líquido na produção de ametófitos com rizóides. As porcentagens de gametófitos com rizóides foram maiores a 25 ºC e menores a 30 °C. As maiores porcentagens de gametófitos com rizóides ocorreram sob 22 e 5% de luz natural nos testes realizados em novembro (2004) e outubro (2005). O uso de reguladores de crescimento em métodos de propagação vegetativa foi ineficiente para a produção de mudas de G. pectinata. Ferns are an important group in the Brazilian flora. They are found at different regions, including open pastureland, dunes, bushes and rocks. Some ferns are pioneers and very efficient in the regeneration of degraded forest fragments. The aim of this study was to analyze the potential of spore germination and gametophyte development of Gleichenella pectinata (Willd) Ching, as well as the morpho-anatomy of gametophytes during their development and to study the effects of different light levels and temperature on their germination. Fertile fronds were collected at the "Unidade de Conservação Ambiental Desterro" (UCAD), Florianópolis-SC. The spores were removed and separated from debris by filtering through lens paper and stored in glass jars under refrigeration at 7 1 ºC. Spores were surface sterilized using a 10% (v/v) solution of commercial bleach (2% of active chlorine) for a period of 15 min and then filtered through sterile filter paper, being washed several times with sterile distilled water. Spores were sown in bottles containing 20 mL mineral medium as proposed by Mohr, modified by Dyer and supplemented with Benomyl 0.01%. All the procedures were carried out in a laminar hood. The germination tests were carried out in growth room at 25 2 oC (30 mol m-2s-1), in growth chamber at 30 2 oC (19 mol m-2s-1) under a 16 hour photoperiod and under the following light levels: 62, 42, 22 and 5% of natural light. Three patterns of young gametophytes were observed: rich chloroplasts chlrocites, filamentous gametophytes without a developed rhizoid and from three to five protallial cell filamentous gametophytes with developed rhizoids. After 14 days, gametophytes presented one or more chlrocites rich in chloroplasts. After 21 days, gametophytes presented three to five protallial cells. After 34 days some gametophytes remained filamentous and other presented a spatulated protallus. After 48 days, they presented the heart shape. The greater percentage of gametophytes with rhizoid was observed after 331 days of storage (18.16 ± 3.54%) for spores colleted in 06/11/2004 and the minor (1.53 ± 1.02 %) for spores colleted in 29/05/2004 and stored for 49 days. No statistically significant differences were observed between results with and without the addition of Benlate® to the mineral medium. The agar gelled medium was not more efficient than the liquid medium in the production of gametophytes with rhizoids. The germination percentages were higher at 25 ºC and lower at 30 °C. The highest percentages of gametophytes with rhizoids were observed at 22 and 5% of natural light in November (2004) and October (2005). The use of growth regulators in vegetative propagation methods was not efficient for the production of G. pectinata plantlets
A Checklist of the Aquatic and Wetland Vascular Plants of Iowa: I. Ferns, Fern Allies, and Dicotyledons
No full textThis paper is an annotated checklist of the aquatic and wetland ferns, fern allies, and dicotyledons of Iowa and is based primarily on published floristic surveys. For each species, information about its habitat , distribution, synonomy , and frequency of occurrence is provided, plus a distribution map. A total of 9 ferns, 6 fern allies, and 262 dicotyledons are considered aquatic or wetland species in Iowa.This article is published as Lammers, T. G. and A. G. van der Valk. 1977. A checklist of the aquatic and wetland vascular plants of Iowa. I. Ferns, fern allies, and dicotyledons. Proceedings of the Iowa Academy of Science 84:41-88. Posted with permission.</p
A Classification for Extant Ferns
No full textWe present a revised classification for extant ferns, with emphasis on ordinal and familial ranks, and a synopsis of included genera. Our classification reflects recently published phylogenetic hypotheses based on both morphological and molecular data. Within our new classification, we recognize four monophyletic classes, 11 monophyletic orders, and 37 families, 32 of which are strongly supported as monophyletic. One new family, Cibotiaceae Korall, is described. The phylogenetic affinities of a few genera in the order Polypodiales are unclear and their familial placements are therefore tentative. Alphabetical lists of accepted genera (including common synonyms), families, orders, and taxa of higher rank are provided
Wildflowers and Ferns of Kentucky
No full textSince Kentucky is situated at a biological crossroads in eastern North America, citizens and visitors to this beautiful state are likely to be greeted by an astonishing variety of wildflowers. This non-technical guide—featuring more than five hundred dazzling full-color photographs by award-winning photographer Thomas G. Barnes—is the state’s indispensable guide to the most common species in the Commonwealth.
With this book, readers will learn to identify and appreciate Kentucky wildflowers and ferns by matching photographs and leaf line drawings to the more than six hundred and fifty species of flowers covered in the book. Extremely practical and simple to use, the guide’s color photographs and line drawings appear with plant descriptions for easy identification, and plants are grouped by flower color and blooming season. Each species listing includes the plant’s common and scientific name, plant family, habitat, frequency, and distribution throughout Kentucky, with similar species listed in the notes.
There is no other volume that covers the flora of Kentucky with such ease of identification. The first new statewide guide to appear in thirty years, with its combination of high quality photographs, illustrations, portability, and easy organization of information, Wildflowers and Ferns of Kentucky is an essential addition to the library or field pack of the wildflower enthusiast, naturalist, and anyone else who loves the outdoors.
Thomas G. Barnes, an extension professor of forestry and wildlife specialist in the Department of Forestry, College of Agriculture at the University of Kentucky, is the author of Kentucky’s Last Great Places.
Former naturalist S. Wilson Francis, Ph.D., is park superintendent at Natural Bridge State Resort Park in Kentucky.
An essential addition to the library or field pack of the wildflower enthusiast or naturalist. —Kentucky Alumni
A striking volume, memorable not only for its color photographs and plant descriptions but also for its introductory exposition of such pertinent matters as finding a good definition for \u27wildflower\u27 and one for \u27weed.\u27 —Mountain Eagle
There isn\u27t a gardener on your gift list who wouldn\u27t be delighted by this book. Don\u27t forget-you need a copy too. —Southsider
Wildflowers and Ferns of Kentucky is an extraordinarily beautiful, helpful, full color, 344-page guide showing 634 of the most common species of native ferns and seed-bearing wildflowers in Kentucky. —State Magazine
Utilizes strong artistic compositions without compromising the identifiable characteristics of the plant. —Burpee Museum of Natural History
This book is an excellent choice for professionals and general readers interested in the flora of Kentucky, adjacent states, and the northeastern US. . . . Highly recommended. —Choice
Contains superb color photographs that make identifying the ferns and flowers much easier. —Modern Mountain Magazine
A must-have for Kentuckiana gardeners. . . . A beautiful book that is easy to use (and carry) as a field guide. —Perry County News
An astonishing variety of plant life exists in Kentucky\u27s diverse geography, and the book represents the impressive mix. . . . Even a botanical novice will benefit from perusing this delightfully blooming book. —Southern Livinghttps://uknowledge.uky.edu/upk_plant_sciences/1005/thumbnail.jp
An Overview and Informal Key of the Ferns of Florida
No full textFlorida's temperate to subtropical climate and abundant moisture create excellent growing conditions for ferns. Tropical storms and winds have transported fern spores to Florida from Caribbean islands and resulted in a high diversity of species. Consequently, Florida has more species of ferns than any state except Hawaii. There are an estimated 123 native fern and fern-like species, and at least 21 exotic and hybrid (crossbreeding of two species) species of ferns found in Florida. This document is Circular 1471, one of a series of the Wildlife Ecology and Conservation Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. Published: May 2005.
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