title: Genetic diversity and geographical dispersal in grapevine clones revealed by microsatellite markers.
abstract: Intravarietal genetic diversification associated with geographical dispersal of a vegetatively propagated species was studied using grapevine Vitis vinifera L. 'Cabernet Sauvignon' as a model. Fifty-nine clonal samples obtained from 7 countries (France, Chile, Spain, Australia, Hungary, USA, and Italy) were analyzed using 84 microsatellite markers. Eighteen polymorphic microsatellite loci (21.4%) were detected, finding 22 different genotypes in the population analyzed with a genetic similarity of over 97%. The presence of chimeric clones was evidenced at locus VMC5g7 by means of a segregation analysis of descendants by self-pollination of a triallelic Chilean clone and by somatic embryogenesis analysis, showing a mutation in L2 cell layer. Only 2 clones (obtained from France and Australia) presented the ancestral genotype, and the most divergent genotype was exhibited by another French clone, which had accumulated 5 somatic mutations. The 2 largest populations considered (from France and Chile) showed a clear divergency in the polymorphisms detected. These antecedents enabled the tracing of geographical dispersal with a phylogenetic hypothesis supporting France as the center of origin of diversification of Cabernet Sauvignon. The results obtained could help to explain diversification processes in other grapevine cultivars. The possibility that this kind of genetic variability occurs in other vegetatively propagated species is discussed, focusing on possible fingerprinting applications.
authors.affiliation: Laboratorio de Biotecnología, Centro de Investigación La Platina, Instituto de Investigaciones Agropecuarias, INIA, Chile, PO Box 439-3 Santiago, Chile.
authors.forename: Ximena
authors.initials: X
authors.lastname: Moncada
authors.forename: Frédérique
authors.initials: F
authors.lastname: Pelsy
authors.forename: Didier
authors.initials: D
authors.lastname: Merdinoglu
authors.forename: Patricio
authors.initials: P
authors.lastname: Hinrichsen
mesh_terms: D002678:Chimera; D002999:Clone Cells; D016000:Cluster Analysis; D014644:Genetic Variation; D018895:Microsatellite Repeats; D010802:Phylogeny; D011786:Quality Control; D027843:Vitis / Q000235:genetics*