Fine-scale genetic structure and marginal processes in an expanding population of Biscutella laevigata L. (Brassicaceae).

Détails

ID Serval
serval:BIB_51F5EC76AF1F
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Titre
Fine-scale genetic structure and marginal processes in an expanding population of Biscutella laevigata L. (Brassicaceae).
Périodique
Heredity
Auteur(s)
Parisod C., Bonvin G.
ISSN
1365-2540 (Electronic)
ISSN-L
0018-067X
Statut éditorial
Publié
Date de publication
2008
Peer-reviewed
Oui
Volume
101
Numéro
6
Pages
536-542
Langue
anglais
Notes
Publication types: Journal Article ; Research Support, Non-U.S. Gov't
Publication Status: ppublish
Résumé
Evolutionary processes acting at the expanding margins of a species' range are still poorly understood. Genetic drift is considered prevalent in marginal populations, and the maintenance of genetic diversity during recolonization might seem puzzling. To investigate such processes, a fine-scale investigation of 219 individuals was performed within a population of Biscutella laevigata (Brassicaceae), located at the leading edge of its range. The survey used amplified fragment length polymorphisms (AFLPs). As commonly reported across the whole species distribution range, individual density and genetic diversity decreased along the local axis of recolonization of this expanding population, highlighting the enduring effect of the historical colonization on present-day diversity. The self-incompatibility system of the plant may have prevented local inbreeding in newly found patches and sustained genetic diversity by ensuring gene flow from established populations. Within the more continuously populated region, spatial analysis of genetic structure revealed restricted gene flow among individuals. The distribution of genotypes formed a mosaic of relatively homogenous patches within the continuous population. This pattern could be explained by a history of expansion by long-distance dispersal followed by fine-scale diffusion (that is, a stratified dispersal combination). The secondary contact among expanding patches apparently led to admixture among differentiated genotypes where they met (that is, a reshuffling effect). This type of dynamics could explain the maintenance of genetic diversity during recolonization.
Mots-clé
Altitude, Amplified Fragment Length Polymorphism Analysis, Brassicaceae/genetics, DNA, Plant/analysis, Europe, Genetic Drift, Genetic Variation, Geography
Pubmed
Web of science
Open Access
Oui
Création de la notice
12/10/2009 14:37
Dernière modification de la notice
08/05/2019 18:36
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