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Taxonomy and cytogeography of the Molinia caerulea complex in central Europe / Martin Dančák in Preslia, vol. 84 (Année 2012)
[article]
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 (Trávníček, 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
Cote Localisation Disponibilité aucun exemplaire Variability and structure of natural populations of Hordeum murinum L. based on morphology / Marta Mizianty in Plant Systematics and Evolution, vol. 261 (Année 2006)
[article]
Titre : Variability and structure of natural populations of Hordeum murinum L. based on morphology Type de document : Livre Auteurs : Marta Mizianty, Auteur Année de publication : 2006 Article en page(s) : pp. 139-150 Langues : Anglais Catégories : [ZG] Pologne
[Espèces (in biblio)] Hordeum murinumMots-clés : variabilité morphologique statistiques nombre de chromosomes aire de répartition Résumé : "Based on a detailed statistical analysis of 19 quantitative and four qualitative characters of 31 samples of Hordeum murinum from Poland, it was stated that the small variability of these characters does not permit to distinguish any intra-specific units. Only a slight geographical differentiation of populations was found. Based on the differences discovered, the populations have been divided into two groups: one with the centre of distribution in the North-East (group E) and the second in South-west Poland (group W). This differentiation might result from the different routes of migration of this species into Poland. The chromosome number (2n = 28) confirms earlier reports from Poland. New data concerning the distribution of H. murinum in north-eastern Poland are also presented. A detailed study on the distribution of H. murinum in Poland is under way." (source : auteur) Type de publication : périodique Référence biblio : Mizianty M., 2006 - Variability and structure of natural populations of Hordeum murinum L. based on morphology. Plant Systematics and Evolution, 261 : 139-150. ID PMB : 69206 Permalink : http://www.cbnbrest.fr/catalogue_en_ligne/index.php?lvl=notice_display&id=69206
in Plant Systematics and Evolution > vol. 261 (Année 2006) . - pp. 139-150[article]Exemplaires
Cote Localisation Disponibilité aucun exemplaire