Proceedings of the XLVI Italian Society of Agricultural Genetics - SIGA Annual Congress

Giardini Naxos, Italy - 18/21 September, 2002

ISBN 88-900622-3-1

Poster Abstract - 1.16

VITIS VINIFERA SSP. SILVESTRIS: GENETIC ISOLATION AND POST-GLACIAL RECOLONISATION OF WILD ITALIAN AND SPANISH POPULATIONS AS ESTIMATED BY AND CHLOROPLAST MICROSATELLITE ANALYSIS

GRASSI F.*, IMAZIO S.**, SGORBATI S.***, SALA F.*, LABRA M.***

*) Department of Biology, University of Milano, Via Celoria, 26 - 201233 Milano, Italy

**) Department of Crop Science, University of Milano, Via Celoria, 2 - 201233 Milano, Italy

***) Department of Environmental Sciences, University of Milano-Bicocca, P.zza della Scienza 1, 20126 Milan, Italy

biodiversity, chloroplast SSR, Molecular tool, nuclear SSR, Vitis vinifera ssp. silvestris

Genetic relationship among six Italian and five Spanish populations of wild grapevine (Vitis vinifera ssp. silvestris) were investigated using nuclear and chloroplast SSR analysis.

Results show that the Italian populations are characterised by high genomic diversity within and among populations, with a peak of heterozygosity for a population collected in Southern Italy. The demonstration of high gene flow among the Italian populations suggests a central role for the Italian peninsula as a principal refugial area of wild grapevines during the last glaciation. On the other hand, the high level of genetic distance detected among the Spanish populations combined with the detection of low gene flow show that these populations suffered a severe bottleneck during their history.

The F_ST values calculated in the case of an Italian population sampled on the island of Sardinia suggest that this population experienced gene flow equally with the Italian and the Spanish populations. This points to Sardinia as a crossing area between Italy and Spain during postglacial recolonization.

By providing information on population history, genetic structure and gene flow, and by identifying areas harbouring high levels of wild grape variability, this study provides the bases for the preservation of biodiversity of wild grapevine.