68 research outputs found

    Seed germination and seedling allogamy in Rosmarinus officinalis: the costs of inbreeding

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    1) Self-pollination by geitonogamy is likely in self-compatible plants that simultaneously expose large numbers of flowers to pollinators. However, the progeny of these plants is often highly allogamous. Although mechanisms to increase cross-pollination have been identified and studied, their relative importance has rarely been addressed simultaneously in plant populations. (2) We used Rosmarinus officinalis to explore the factors that influence the probability of self-fertilization due to geitonogamy or that purge its consequences, focusing on their effect on seed germination and allogamy rate. For doing this, we experimentally tested the effects of geitonogamy on the proportion of filled seeds and how it influences germination rates. Then during two field seasons, we studied how life-history and flowering traits of individuals influence seed germination and allogamy rates of their progeny in wild populations at the extremes of the altitudinal range. The traits considered were plant size, population density, duration of the flowering season, number of open flowers, flowering synchrony among individuals within populations, and the proportion of male-sterile flowers. (3) We found that most seeds obtained experimentally from self-pollinations were apparently healthy but in fact empty, and that the presence of filled seeds drove the differences in germination rates between self- and cross-pollination experiments. Plants from wild populations consistently showed low germination rates and high rates of allogamy as determined with microsatellites. Germination rates related positively to the length of the flowering season, flowering synchrony and the rate of male-sterile flowers whereas the rate of allogamous seedlings was positively related only to the rate of male-sterile flowers. (4) Rosemary plants purge most of the inbreeding caused by its pollination system by aborting seeds. This study showed that the rates of seed germination and of the resulting allogamy are a function of a complex combination of factors that vary in space and time. Male sterility of flowers, length of the flowering season and flowering synchrony of individuals within populations all favor high rates of cross-pollination, therefore increasing germination and allogamy rates. These flowering traits appear to be highly plastic and respond to local and seasonal environmental conditions

    Population genetic structure of a sandstone specialist and a generalist heath species at two levels of sandstone patchiness across the Strait of Gibraltar

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    Many habitat specialist species are originally composed of small, discontinuous populations because their habitats are naturally fragmented or patchy. They may have suffered the long-term effects of natural patchiness. Mediterranean heathlands, a representative habitat in the Strait of Gibraltar region, are associated with nutrient-poor, acidic sandstone soils. Sandstone soil patches in the African side of the Strait (Tangier) are, in general, smaller and more scattered than in the European side (Algeciras). In this study, we analyze the effect of this sandstone patchiness on the population genetic diversity and structure of two Erica species from these Mediterranean heathlands that differ in their edaphic specificity, E. australis, sandstone specialist, and E. arborea, generalist. Average levels of within-population genetic diversity and gene flow between populations were significantly lower in Tangier (high sandstone patchiness) than in Algeciras (low patchiness) for the sandstone specialist, whereas no differences between both sides of the Strait were detected in the edaphic generalist. Since most endemic species in Mediterranean heathlands of the Strait of Gibraltar are sandstone specialists, these results highlight an increased vulnerability to loss of genetic diversity and local extinction of the heathland endemic flora in the Tangier side of the Strait of Gibraltar. © 2014 Gil-López et al.Project BREATHAL (CGL2011-28759/BOS) was financed by the Spanish Ministerio de Ciencia e Innovación.Peer Reviewe

    An eco-physiological and biotechnological approach to conservation of the world-wide rare and endangered aquatic liverwort Riella helicophylla (Bory et Mont.) Mont.

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    The rare aquatic liverwort Riella helicophylla (Bory et Mont.) Mont., inhabitant of temporary shallow ponds around the Mediterranean basin, is considered threatened throughout its distribution range. In addition, little is known of its biology and ecology or of its role in such an important ecosystem where envi- ronmental conditions vary yearly in unpredictable ways. In these variable habitats, due to the seasonal fluc- tuation of water levels, there is no guarantee of yearly spore input into the spore bank. Spore germination rate and the effects of different culture media in an axenic culture establishment, as well as propagation proce- dures of R. helicophylla, were tested. New insights into the ecology and biology of R. helicophylla are given. Spore dormancy is documented, and the protocols for the in vitro culture establishment, propagation and ac- climatization of this liverwort are developed. Dry storage at 20 ± 2 °C for about three months broke the dor- mancy of spores, which subsequently germinated in a high percentage (over 90%). A two phase (solid and liquid) culture media system was developed for the purpose of achieving fully developed gametophytes. The liquid phase contained electrolytes simulating brackish water

    World checklist of hornworts and liverworts

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    A working checklist of accepted taxa worldwide is vital in achieving the goal of developing an online flora of all known plants by 2020 as part of the Global Strategy for Plant Conservation. We here present the first-ever worldwide checklist for liverworts (Marchantiophyta) and hornworts (Anthocerotophyta) that includes 7486 species in 398 genera representing 92 families from the two phyla. The checklist has far reaching implications and applications, including providing a valuable tool for taxonomists and systematists, analyzing phytogeographic and diversity patterns, aiding in the assessment of floristic and taxonomic knowledge, and identifying geographical gaps in our understanding of the global liverwort and hornwort flora. The checklist is derived from a working data set centralizing nomenclature, taxonomy and geography on a global scale. Prior to this effort a lack of centralization has been a major impediment for the study and analysis of species richness, conservation and systematic research at both regional and global scales. The success of this checklist, initiated in 2008, has been underpinned by its community approach involving taxonomic specialists working towards a consensus on taxonomy, nomenclature and distribution

    A miniature world in decline: European Red List of Mosses, Liverworts and Hornworts

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    AimThis Red List is a summary of the conservation status of the European species of mosses, liverworts and hornworts, collectively known as bryophytes, evaluated according to IUCN’s Guidelines for Application of IUCN Red List Criteria at Regional Level. It provides the first comprehensive, region-wide assessment of bryophytes and it identifies those species that are threatened with extinction at a European level, so that appropriate policy measures and conservation actions, based on the best available evidence, can be taken to improve their status.ScopeAll bryophytes native to or naturalised in Europe (a total of 1,817 species), have been included in this Red List. In Europe, 1,796 species were assessed, with the remaining 21 species considered Not Applicable (NA). For the EU 28, 1,728 species were assessed, with a remaining 20 species considered NA and 69 species considered Not Evaluated (NE). The geographical scope is continentwide, extending from Iceland in the west to the Urals in the east, and from Franz Josef Land in the north to theCanary Islands in the south. The Caucasus region is not included. Red List assessments were made at two regional levels: for geographical Europe and for the 28 Member States of the European Union.ResultsOverall, 22.5% of European bryophyte species assessed in this study are considered threatened in Europe, with two species classified as Extinct and six assessed as Regionally Extinct (RE). A further 9.6% (173 species) are considered Near Threatened and 63.5% (1,140 species) are assessed as Least Concern. For 93 species (5.3%), there was insufficient information available to be able to evaluate their risk of extinction and thus they were classified as Data Deficient (DD). The main threats identified were natural system modifications (i.e., dam construction, increases in fire frequency/intensity, and water management/use), climate change (mainly increasing frequency of droughts and temperature extremes), agriculture (including pollution from agricultural effluents) and aquaculture.RecommendationsPolicy measures• Use the European Red List as the scientific basis to inform regional/national lists of rare and threatened species and to identify priorities for conservation action in addition to the requirements of the Habitats Directive, thereby highlighting the conservation status of bryophytes at the regional/local level.• Use the European Red List to support the integration of conservation policy with the Common Agricultural Policy (CAP) and other national and international policies. For example, CAP Strategic Plans should include biodiversity recovery commitments that could anticipate, among others, the creation of Important Bryophyte Areas. An increased involvement of national environmental agencies in the preparation of these strategic plans, and more broadly in ongoing discussions on the Future CAP Green Architecture, would likely also ensure the design of conservation measures better tailored to conserve bryophytes in agricultural landscapes.• Update the European Red List every decade to ensure that the data remains current and relevant.• Develop Key Biodiversity Areas for bryophytes in Europe with a view to ensuring adequate site-based protection for bryophytes.Research and monitoring• Use the European Red List as a basis for future targeted fieldwork on possibly extinct and understudied species.• Establish a monitoring programme for targeted species (for example, threatened species and/or arable bryophytes).• Use the European Red List to obtain funding for research into the biology and ecology of key targeted species.Action on the ground• Use the European Red List as evidence to support multi-scale conservation initiatives, including designation of protected areas, reform of agricultural practices and land management, habitat restoration and rewilding, and pollution reduction measures.• Use the European Red List as a tool to target species that would benefit the most from the widespread implementation of the solutions offered by the 1991 Nitrates Directive (Council Directive 91/676/EEC), including the application of correct amounts of nutrients for each crop, only in periods of crop growth under suitable climatic conditions and never during periods of heavy rainfall or on frozen ground, and the creation of buffer zones to protect waters from run-off from the application of fertilizers.Ex situ conservation• Undertake ex situ conservation of species of conservation concern in botanic gardens and spore and gene banks, with a view to reintroduction where appropriate.</p

    Isolation and characterization of microsatellite loci in the carnivorous subshrub Drosophyllum lusitanicum (Drosophyllaceae)

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    Funding was provided by projects BREATHAL (CGL2011-28759/BOS; Spanish Ministerio de Ciencia e Innovación-MICINN) and project P07-RNM-02869 (Junta de Andalucía, Spain). M.P. and M.J.G.-L. were supported by an FPI and FPU Ph.D. grants, respectively, from MICINN. J.G.S.-M. was supported by a ‘Ramón y Cajal’ (MICINN-RYC, Spain) postdoctoral contract.Peer Reviewe

    New national and regional bryophyte records, 37

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    Ellis et al.Funding was provided by the Natural Environment Research Council. All are gratefully acknowledged. The work of M. J. Cano has been carried out with financial support of the Spanish government (projects CGL2012-30721 and CGL2010-15959 co-financed by FEDER). G. Asthana, S. Yadav, and S. Srivastava are thankful to Ministry of Environment & Forests, New Delhi for financial Assistance. The research of M. V. Dulin was performed under the financial support of the Russian Foundation for Basic Research (project no. 12-04-01476-a) and by the Program of UB RAS ‘Living Nature’, project No. 12-P-4-1018 ‘Specific, cenotic and ecosystem diversity of landscapes in the UNESCO World Heritage Site “Virgin Komi Forests”’. The National Geographic Society Waitt Grant generously provided funding for the field work, without which the expedition may not have taken place. The African Butterfly Research Institute also helped with funding, and with logistical support. The contributions by R. Ochyra have been financially supported by the National Centre of Science through grant no. 2 P04G 043 29. The field work of R. Ochyra and Marc Lebouvier on Îles Crozet and Îles Kerguelen was organized within the programme 136 ECOBIO of the French Polar Institute (IPEV), the logistic support for the field work of R. Ochyra and V. R. Smith on the Prince Edward Islands was obtained from the South African Department of Environmental affairs and Tourism. F. Puche and M. Brugués acknowledge funds from the Spanish Ministry of Science and Innovation (project CGL2009-09530, Flora Briofítica Ibérica). J. G. Segarra-Moragues benefited from a Spanish Ministry of Science and Innovation ‘Ramón y Cajal’ postdoctoral contract. The research of E. Fuertes was funded by the Spanish Ministry of Science and Innovation, Project: Ref. CGL2009-13622. S. Ştefănuţ is grateful to Beata Papp for research support from the HU-TAF-1722 of the SYNTHESYS Project (http://www.synthesys.info/), which is financed by European Community Research Infrastructure Action under the FP7 ‘Capacities’ Program.Peer Reviewe

    Burning phylogenies: Fire, molecular evolutionary rates, and diversification

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    10 páginas, 1 figura, 3 tablas.Mediterranean-type ecosystems are among the most remarkable plant biodiversity "hot spots" on the earth, and fire has traditionally been invoked as one of the evolutionary forces explaining this exceptional diversity. In these ecosystems, adult plants of some species are able to survive after fire (resprouters), whereas in other species fire kills the adults and populations are only maintained by an effective post-fire recruitment (seeders). Seeders tend to have shorter generation times than resprouters, particularly under short fire return intervals, thus potentially increasing their molecular evolutionary rates and, ultimately, their diversification. We explored whether seeder lineages actually have higher rates of molecular evolution and diversification than resprouters. Molecular evolutionary rates in different DNA regions were compared in 45 phylogenetically paired congeneric taxa from fire-prone Mediterranean-type ecosystems with contrasting seeder and resprouter life histories. Differential diversification was analyzed with both topological and chronological approaches in five genera (Banksia, Daviesia, Lachnaea, Leucadendron, and Thamnochortus) from two fire-prone regions (Australia and South Africa). We found that seeders had neither higher molecular rates nor higher diversification than resprouters. Such lack of differences in molecular rates between seeders and resprouters-which did not agree with theoretical predictions-may occur if (1) the timing of the switch from seeding to resprouting (or vice versa) occurs near the branch tip, so that most of the branch length evolves under the opposite life-history form; (2) resprouters suffer more somatic mutations and therefore counterbalancing the replication-induced mutations of seeders; and (3) the rate of mutations is not related to shorter generation times because plants do not undergo determinate germ-line replication. The absence of differential diversification is to be expected if seeders and resprouters do not differ from each other in their molecular evolutionary rate, which is the fuel for speciation. Although other factors such as the formation of isolated populations may trigger diversification, we can conclude that fire acting as a throttle for diversification is by no means the rule in fire-prone ecosystems.We thank R. Ree and B. R. Moore for their advice on the KIT and Sym- meTREE softwares and H. Dopazo for helping with the Phylemon server. B. Lamont provided fire-trait information on some Banksia species. We also thank T. Barraclough, P. Catalin, S. González-Martínez, B. Lamont, J. Pannell, X. Pic6, and R. Ree for helpful comments on the manuscript. This work has been partially financed by the PERSIST project (CGL2006- 07126/BOS) to JGP and by a research grant attached to a "Ramón y Cajal" contract to FO. JGS-M was granted a contract from the I3P program.Peer reviewe

    Secondary compounds enhance flammability in a Mediterranean plant

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    Some plant secondary compounds, such as terpenes, are very flammable; however, their role in enhancing plant flammability is poorly understood and often neglected in reviews on plant chemical ecology. This is relevant as there is growing evidence that flammability-enhancing traits are adaptive in fire-prone ecosystems. We analyzed the content of monoterpenes and sesquiterpenes, performed flammability tests and genotyped microsatellite markers, all in the same individuals of Rosmarinus officinalis, to evaluate the link between the content of terpenes, flammability and the genetic similarity among individuals. The results suggest that terpenes enhance flammability in R. officinalis, and that variability in flammability among individuals is likely to have a genetic basis. Overall our results suggest that the capacity to produce and store terpenes can be considered a flammability-enhancing trait and could have an adaptive value in fire-prone ecosystems.This work was funded by the VIRRA and TREVOL projects (CGL2009-12048/BOS, CGL2012-39938-C02-01) from the Spanish government. B. M. was supported by a grant from the Portuguese government (Fundação para a Ciência e a Tecnologia; SFRH/BPD/90277/2012), G. A. A. by a Juan de la Cierva (JDC-2009-5067) post-doc from the Spanish Ministerio de Ciencia e Innovación (MICINN), and J. G. S.-M. by a Ramón y Cajal postdoc also from MICINN.Peer Reviewe
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