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Détail de l'auteur
Auteur Bohumil Travnicek (TrávnÃček, Bohumil) |
Documents disponibles écrits par cet auteur
Affiner la rechercheNatural hybridization between diploid Ficaria calthifolia and tetraploid Ficaria verna subsp. verna in central Europe : evidence from morphology, ecology and life-history traits / Ondrej Popelka in Preslia, vol. 91 (Année 2019)
Titre : Natural hybridization between diploid Ficaria calthifolia and tetraploid Ficaria verna subsp. verna in central Europe : evidence from morphology, ecology and life-history traits Type de document : Livre Auteurs : Ondrej Popelka, Auteur ; Bohumil Travnicek (TrávnÃček, Bohumil), Auteur ; Pavla Siková (%u0160iková, Pavla), Auteur ; Michaela Jandová, Auteur ; Martin Duchoslav, Auteur Année de publication : 2019 Article en page(s) : pp. 179-212 Langues : Anglais Catégories : [Espèces (in biblio)] Ficaria calthifolia
[Espèces (in biblio)] Ficaria verna
[Thèmes] TaxonomieMots-clés : Ficaria × sellii bulbille cytométrie hybridation morphométrie phénologie viabilité du pollen polyploïdie Résumé : "The genusFicariais a taxonomically intricate group in which polyploidization and hybridizationcontribute to taxa diversification. Incentral Europe, populations of diploidF. calthifoliaandtetraploidF. vernasubsp.vernaoccasionally come into contact, which results in an interspecifictriploid hybrid, as recently demonstrated using molecular markers, genome size estimation andexperimental crossing. In this study, we aimedto estimate the frequency and distribution of thetriploid hybrid in central Europe, to identify those phenotypic traits that can be used to discrimi-nate between hybrid and parental taxa and compare the phenology, pollen viability, sexual andasexual reproduction and niche differentiation of the triploid hybrid and parental taxa. Flow-cytometry analyses of 1171 individuals sampledfrom 67 localities revealed that triploid hybridswere regularly found at 89% of the sites sampled where there were sympatric populations of bothparental taxa, with a mean percentage of 19.4% occurring at sites where there was a mixture ofcytotypes. No pure hybrid population was found. The hybrids were intermediate between theparental taxa in most morphological characters and did not show any novel morphological charac-ters. The characters that best differentiate the taxonomic groups were the production of axillarybulbils, aborted and well-developed achenes, leaf shape and plant habit. Almost all hybrids weresexually sterile: the pollen viability was considerably reduced (mean 8.4%) and on average 98%of the achenes were aborted. Local dispersal of the hybrids is possible through the production ofbulbils in the leaf axils, although the number of bulbils per node and the mean weight of one bulbilwere two and three times lower in the hybrid than inF. vernasubsp.verna.The hybrid niche wasintermediate between those of the parental taxa but shifted slightly towards that ofF. vernasubsp.verna. In addition, the taxonomic and nomenclatural treatment of the hybrid, which is describedasFicaria×selliiDuchoslav, Popelka et Trávn., as well as a key for identifying the central Euro-pean taxa ofFicaria, are presented." (source : auteurs) Type de publication : périodique Référence biblio : Popelka O., Travnicek B., Siková P., Jandová M., Duchoslav M., 2019 - Natural hybridization between diploid Ficaria calthifolia and tetraploid Ficaria verna subsp. verna in central Europe : evidence from morphology, ecology and life-history traits. Preslia, 91 : 179-212. ID PMB : 69008 DOI : 10.23855/preslia.2019.179 Permalink : http://www.cbnbrest.fr/catalogue_en_ligne/index.php?lvl=notice_display&id=69008
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Titre : Taxonomy and cytogeography of the Molinia caerulea complex in central Europe Type de document : périodique Auteurs : Martin Dančák, Auteur ; Martin Duchoslav, Auteur ; Bohumil Travnicek (TrávnÃček, Bohumil), Auteur Année de publication : 2012 Article en page(s) : pp. 351-384 Langues : Anglais Catégories : [Espèces (in biblio)] Molinia caerulea
[Thèmes] TaxonomieMots-clés : cytogéographie polyploïdie nombre de chromosomes Résumé : "Perennial grasses belonging to the genus Molinia are widespread in most of Europe and consist of a polyploid complex of closely related taxa with a confusing taxonomy. Based on extensive sampling at 241 localities in Europe, four cytotypes were identified based on chromosome counts and results of flow cytometry: tetraploids (2n = 36), hexaploids (2n = 54), octoploids (2n = 72) and dodecaploids (2n = 108). While tetra- and dodecaploids were commonly recorded, octoploids were less common and only two hexaploid individuals were identified. Previously reported decaploid counts (2n = 90) from central Europe are probably erroneous and refer to 2n = 108. The tetraploid cytotype is distributed throughout Europe and broadly sympatric with other cytotypes. Octo- and dodecaploids were spatially separated with dodecaploids occurring in the western, central and south-central part of Europe and octoploids in the east-central and southeastern part of Europe. All quantitative characters measured (lengths of lemmas, anthers, caryopses and stomata, lengths of the longest hair on the callus and diameter of the culm below the panicle) showed a linear trend across ploidy levels. Tetra-, octo- and dodecaploid cytotypes formed almost non-overlapping groupings in principal component and discriminant analyses of morphological characters. The following taxonomic concept of this complex is proposed: Molinia caerulea (L.) Moench is a predominantly tetraploid taxon incorporating very rarely reported hexaploid and perhaps also diploid plants; higher cytotypes (2n = 8x, 12x) are considered to be M. arundinacea Schrank, consisting of two subspecies: a dodecaploid subspecies occurring in the southern and western part of central Europe and the octoploid Molinia arundinacea subsp. freyi Dančák in east-central and southeastern Europe." (source : auteurs) Type de publication : périodique Référence biblio : Dančák M., Duchoslav M., Travnicek B., 2012 - Taxonomy and cytogeography of the Molinia caerulea complex in central Europe. Preslia, 84 : 351-384. ID PMB : 72146 Permalink : http://www.cbnbrest.fr/catalogue_en_ligne/index.php?lvl=notice_display&id=72146
in Preslia > vol. 84 (Année 2012) . - pp. 351-384[article]Exemplaires
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Titre : Taxonomy of Rubus ser. Discolores in the Czech Republic and adjacent regions Type de document : Livre Auteurs : Bohumil Travnicek (TrávnÃček, Bohumil), Auteur ; J. Zazvorka, Auteur Année de publication : 2005 Article en page(s) : pp. 1-88 Langues : Anglais Catégories : [Thèmes] Taxonomie Mots-clés : apogamie central Europe Czech Republic chorologie Rosaceae Rubus ser. Radula Résumé : "The current state of the taxonomy of Rubus ser. Discolores in Czech Republic is summarized. Since 1995, when the group was studied in the Flora of the Czech Republic, 6 new species have been recognized, some of which are also known from adjacent areas. They are described in the present study: R. austroslovacus, R. flos-amygdalae, R. guttiferus, R. parthenocissus, R. pericrispatus and R. portae-moravicae. The first 5 belong to the group of triploid species close to R. montanus and R. grabowskii, whilst R. portae-moravicae is related to R. praecox. Two additional species, originally recognized under provisional names, were identical to species described earlier: R. perperus and R. phyllostachys; the latter is also found in Slovakia. At present, 17 indigenous species, one naturalized alien (R. armeniacus) and one rare garden escape (R. ulmifolius [R. inermis]) of the ser. Discolores are known to occur in the Czech Republic. Distribution data and a key for the identification of all the species are presented. " Type de publication : périodique Référence biblio : Travnicek B., Zazvorka J., 2005 - Taxonomy of Rubus ser. Discolores in the Czech Republic and adjacent regions. Preslia, 77 (1) : 1-88. En ligne : http://www.preslia.cz/doi/preslia.2018.387.html Format de la ressource électronique : document Permalink : http://www.cbnbrest.fr/catalogue_en_ligne/index.php?lvl=notice_display&id=67746
in Preslia > vol. 77, n°1 (Année 2005) . - pp. 1-88[article]Exemplaires
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