Résultat de la recherche
2 recherche sur le mot-clé
'taille du génome' 
trié(s) par (Pertinence décroissant(e), Titre croissant(e)) Affiner la recherche Générer le flux rss de la recherche
Partager le résultat de cette rechercheGenome Size Variation and Evolution in Veronica / Dirk Albach in Annals of Botany, vol. 94, n°6 (Année 2004)
Titre : Genome Size Variation and Evolution in Veronica Auteurs : Dirk Albach, Auteur ; Johann Greilhuber, Auteur Article en page(s) : pp. 897-911 Langues : Anglais (eng) Catégories : [Espèces (in biblio)] Veronica Mots-clés : cycle biologique annuel ADN taille du génome nucléotype autofécondation phylogénitique Résumé : "The amount of DNA per chromosome set is known to be a fairly constant characteristic of a species. Its interspecific variation is enormous, but the biological significance of this variation is little understood. Some of the characters believed to be correlated with DNA amount are alpine habitat, life history and breeding system. In the present study, the aim is to distinguish between direct causal connections and chance correlation of the amount of DNA in the genus Veronica. Estimates of DNA amount were analysed for 42 members of Veroniceae in connection with results from a phylogenetic analysis of plastid trnL-F DNA sequences and tested correlations using standard statistical tests, phylogenetically independent contrasts and a model-based generalized least squares method to distinguish the phylogenetic effect on the results. There appears to be a lower upper limit for DNA amount in annuals than in perennials. Most DNAC-values in Veroniceae are below the mean DNA C-value for annuals in angiosperms as a whole. However, the long-debated correlation of low genome size with annual life history is not significant (P = 0.12) using either standard statistical tests or independent contrasts, but it is significant with the generalized least squares method (P < 0.01). The correlation of annual life history and low genome size found in earlier studies could be due to the association of annual life history and selfing, which is significantly correlated with low genome size using any of the three tests applied. This correlation can be explained by models showing a reduction in transposable elements in selfers. A significant correlation of higher genome sizes with alpine habitats was also detected." (source : auteurs) Type de publication : périodique Référence biblio : Albach D., Greilhuber J., 2004 - Genome Size Variation and Evolution in Veronica. Annals of Botany, 94 (6) : 897-911. ID PMB : 72801 Permalink : http://www.cbnbrest.fr/catalogue_en_ligne/index.php?lvl=notice_display&id=72801
in Annals of Botany > vol. 94, n°6 (Année 2004) . - pp. 897-911[article]Exemplaires(0)
Disponibilité aucun exemplaire
Titre : American cudweeds (Gamochaeta; Gnaphalium s.l., Asteraceae) in Belgium and the Netherlands Auteurs : Filip Verloove, Auteur ; Gerard M. Dirkse, Auteur ; Sofie Meeus, Auteur Article en page(s) : pp. 36-51 Langues : Anglais (eng) Catégories : [ZG] Belgique
[ZG] Pays-Bas
[Espèces (in biblio)] Gnaphalium
[Thèmes] Flore vasculaire (phanérogames et cryptogames vasculaires)Mots-clés : taille du génome identification flore urbaine plante naturalisée Résumé : "In recent years several species of American cudweeds (Gamochaeta; Gnaphalium s.l.) have increasingly been recorded in Belgium and the Netherlands, especially (but not exclusively) in urban habitats. Since these species are naturalizing – at least one even on a relatively large scale – assessing their genuine identity is necessary. Three species are eventually accepted: G. coarctata (previously erroneously ascribed to G. purpurea), G. pensylvanica and G. subfalcata (surprisingly often overlooked for the native species Gnaphalium sylvaticum). In this paper all are copiously depicted and characters useful for their separation are discussed. A key for their identification is also presented, as are details about their distribution and habitat preferences in Belgium and the Netherlands. The naturalized populations reported in this paper are probably the northernmost known worldwide. Finally, the genome size was assessed for several accessions. It turned out that genome size does hardly allow to separate G. pensylvanica and G. subfalcata." (source : auteurs) Type de publication : périodique Référence biblio : Verloove F., Dirkse G., Meeus S., 2023 - American cudweeds (Gamochaeta; Gnaphalium s.l., Asteraceae) in Belgium and the Netherlands. Gorteria, 45 : 36-51. ID PMB : 72797 Permalink : http://www.cbnbrest.fr/catalogue_en_ligne/index.php?lvl=notice_display&id=72797
in Gorteria > vol. 45 (Année 2023) . - pp. 36-51[article]Exemplaires(0)
Disponibilité aucun exemplaire
