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31.
Josef Holub 《Folia Geobotanica》1983,18(2):203-206
On the basis of taxonomic and nomenclatural revisions of various plant groups 37 new nomenclatural combinations are proposed mostly for European phanerogamous taxa (21 for species, 14 for subspecies, 2 for hybrids.)Medicula Medicus,Pseudofumaria Medicus andThlasidia Rafin. are accepted as taxonomically justified genera and correct generic names.Dactylorhiza longebracteata (F. W. Schmidt)Holub is proposed instead ofD. fuchsii (Druce) Soó, andHylotelephium triphyllum (Haworth) Holub isstead ofH. purpureum (L.)Holub. 相似文献
32.
Josef Holub 《Folia Geobotanica》1983,18(3):325-328
A list including 114 selected subspecies names from the bookSchübler andMartens, Flora von Würtemberg, 1834 is given. Twenty of them are very important for the present taxonomic classification. 相似文献
33.
Josef Holub 《Folia Geobotanica》1983,18(4):439-442
Four earlier proposed and invalidly published generic names ofLycopodiaceae are validated:Lateristachys (type:Lycopodium laterale R. Br.),Lycopodiastrum (type:Lycopodium casuarinoides Spring),Pseudodiphasium (type:Lycopodium volubile G. Forster) andPseudolycopodium (type:Pseudolycopodium densum (Rothm.) Holub). A new genusPseudolycopodiella (type:Lycopodium carolinianum L.) is described. New nomenclatural combinations are proposed for 17 species of these genera and ofLycopodiella. 相似文献
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Ultrathin sectioning of submerged mycelium of Claviceps purpurea Tul. producing clavine alkaloids revealed yeast-like budding resulting in asexual sporesblastospores. These deciduous spores were born by extended hyphal cells and retained the same ultrastructure of cell organelles. Both the extended hyphae and the blastospores resembled the cells of ergot sclerotial tissue. A surface culture of C. purpurea Tul. producing no alkaloids was used as a reference. 相似文献
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Kathy Darragh Gabriela Montejo‐Kovacevich Krzysztof M. Kozak Colin R. Morrison Clarisse M. E. Figueiredo Jonathan S. Ready Camilo Salazar Mauricio Linares Kelsey J. R. P. Byers Richard M. Merrill W. Owen McMillan Stefan Schulz Chris D. Jiggins 《Ecology and evolution》2020,10(9):3895-3918
In many animals, mate choice is important for the maintenance of reproductive isolation between species. Traits important for mate choice and behavioral isolation are predicted to be under strong stabilizing selection within species; however, such traits can also exhibit variation at the population level driven by neutral and adaptive evolutionary processes. Here, we describe patterns of divergence among androconial and genital chemical profiles at inter‐ and intraspecific levels in mimetic Heliconius butterflies. Most variation in chemical bouquets was found between species, but there were also quantitative differences at the population level. We found a strong correlation between interspecific chemical and genetic divergence, but this correlation varied in intraspecific comparisons. We identified “indicator” compounds characteristic of particular species that included compounds already known to elicit a behavioral response, suggesting an approach for identification of candidate compounds for future behavioral studies in novel systems. Overall, the strong signal of species identity suggests a role for these compounds in species recognition, but with additional potentially neutral variation at the population level. 相似文献
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Maarten J. E. Broekman Helene C. Muller‐Landau Marco D. Visser Eelke Jongejans S. J. Wright Hans de Kroon 《Ecology letters》2019,22(11):1957-1975
Many empirical studies motivated by an interest in stable coexistence have quantified negative density dependence, negative frequency dependence, or negative plant–soil feedback, but the links between these empirical results and ecological theory are not straightforward. Here, we relate these analyses to theoretical conditions for stabilisation and stable coexistence in classical competition models. By stabilisation, we mean an excess of intraspecific competition relative to interspecific competition that inherently slows or even prevents competitive exclusion. We show that most, though not all, tests demonstrating negative density dependence, negative frequency dependence, and negative plant–soil feedback constitute sufficient conditions for stabilisation of two‐species interactions if applied to data for per capita population growth rates of pairs of species, but none are necessary or sufficient conditions for stable coexistence of two species. Potential inferences are even more limited when communities involve more than two species, and when performance is measured at a single life stage or vital rate. We then discuss two approaches that enable stronger tests for stable coexistence‐invasibility experiments and model parameterisation. The model parameterisation approach can be applied to typical density‐dependence, frequency‐dependence, and plant–soil feedback data sets, and generally enables better links with mechanisms and greater insights, as demonstrated by recent studies. 相似文献
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