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Ecological hybrid speciation in central-European species of Bolboschoenus : genetic and morphological evaluation / Sona Pisova in Preslia, vol. 89 (Année 2017)
[article]
Titre : Ecological hybrid speciation in central-European species of Bolboschoenus : genetic and morphological evaluation Type de document : Livre Auteurs : Sona Pisova, Auteur ; Zdenka Hroudová, Auteur ; Zuzana Chumova, Auteur ; Tomas Fer, Auteur Année de publication : 2017 Article en page(s) : pp. 17-39 Langues : Anglais Catégories : [Espèces (in biblio)] Bolboschoenus
[ZG] Europe centraleMots-clés : spéciation hybride morphologie génétique Résumé : "Divergent natural selection is known to facilitate speciation in many taxa. The genus Bolboschoenus (Cyperaceae) is a model group for investigating ecological and homoploid hybrid speciation. Four taxa of Bolboschoenus occur in central Europe: the halophyte B. maritimus and glycophytes B. laticarpus, B. planiculmis and B. yagara. These species differ in their ecological niches. Such ecological and/or geographical isolation is critical for homoploid hybrid speciation. The determination of species of Bolboschoenus is based on morphological characters of the inflorescence and on achene shape and anatomy. On the basis of its intermediate morphology, chromosome number and ecological amplitude B. laticarpus is thought to be a hybrid. In order to determine the validity of morphological species and the possible hybrid origin of B. laticarpus we used amplified fragment length polymorphisms (AFLPs) as molecular markers and compared different genetic groups defined using STRUCTURE analysis with morphological data. The morphological classification of central-European species of Bolboschoenus was confirmed. Plants of heterogeneous genotypes were also found to be intermediate individuals resulting from spontaneous hybridization. Hybrid origin of B. laticarpus, which is genetically and morphologically intermediate between B. yagara and B. planiculmis, was elucidated. Inflorescence characters were less important for determining species than anatomical characters of achenes (widths of the exocarp and mesocarp)." (source : auteurs) Type de publication : périodique Référence biblio : Pisova S., Hroudová Z., Chumova Z., Fer T., 2017 - Ecological hybrid speciation in central-European species of Bolboschoenus : genetic and morphological evaluation. Preslia, 89 : 17-39. ID PMB : 69472 DOI : 10.23855/PRESLIA.2017.017 En ligne : http://www.preslia.cz/P171Pisova.pdf Format de la ressource électronique : document Permalink : http://www.cbnbrest.fr/catalogue_en_ligne/index.php?lvl=notice_display&id=69472
in Preslia > vol. 89 (Année 2017) . - pp. 17-39[article]Exemplaires
Cote Localisation Disponibilité aucun exemplaire Morphometric comparison of British Pseudorchis albida with Icelandic P. straminea (Orchidaceae: Orchidinae) / Richard M. Bateman in New Journal of botany, vol. 7, n°2-3 (Année 2017)
[article]
Titre : Morphometric comparison of British Pseudorchis albida with Icelandic P. straminea (Orchidaceae: Orchidinae) Type de document : Livre Auteurs : Richard M. Bateman, Auteur ; Paula J. Rudall, Auteur ; I. Denholm, Auteur Année de publication : 2018 Article en page(s) : pp. 78-93 Langues : Anglais Catégories : [Espèces (in biblio)] Pseudorchis
[Espèces (in biblio)] Pseudorchis albida
[ZG] Royaume-Uni et Irlande
[Thèmes] TaxonomieMots-clés : conservation morphométrie spéciation aire de répartition Résumé : "Although the majority of taxonomic studies of European orchids treat Pseudorchis as a monotypic genus, some observers have argued that the apparently circumboreal segregate P. straminea should also be treated as a full species. Here, we compare detailed in vivo measurements of 55 plants from nine populations of P. albida in Britain with ten plants from three populations of P. straminea in Iceland, We apply morphometric statistics to data for 31 morphometric characters, culled from an original set of 36. We also review current (limited) DNA-based evidence of their evolutionary divergence. Of the 31 variable morphometric characters, 14 help to distinguish the two species, including labellum dimensions, spur length, flower colour, bract and leaf lengths, leaf colour and apical hooding. Molecular divergence (notably in ITS) approximates the lowest level needed for acceptance of species-level distinction, but thus far, the molecular information is typological and does not encompass seemingly intermediate populations of ‘P. tricuspis’ occurring in the mountains of central Europe. Pseudorchis has the potential to become a valuable model system for the study of speciation and subsequent inter-/post-glacial migration. Despite persistent rumours, we found no evidence that P. straminea (or ‘P. tricuspis’) occurs in the British Isles; nonetheless, this species should continue to be sought in suitable habitats in northern Scotland. Morphological variation within P. albida is comparatively low, though the most exposed of our study populations exhibits (presumably ecophenotypic) dwarfing." (source : auteurs) Type de publication : périodique Référence biblio : Bateman R., Rudall P., Denholm I., 2018 - Morphometric comparison of British Pseudorchis albida with Icelandic P. straminea (Orchidaceae: Orchidinae). New Journal of botany, 7 : 78-93. ID PMB : 66863 Permalink : http://www.cbnbrest.fr/catalogue_en_ligne/index.php?lvl=notice_display&id=66863
in New Journal of botany > vol. 7, n°2-3 (Année 2017) . - pp. 78-93[article]Exemplaires
Cote Localisation Disponibilité P0130-5 Brest Exclu du prêt