Data from: Study of genetic variability in Vitis vinifera L. germplasm by high-throughput Vitis18kSNP array: the case of Georgian genetic resources

Background: Georgia, in the Caucasian region, is considered the first
domestication centre of grapevine. This country is characterized by high
morphological variability of cultivated (Vitis vinifera L. subsp. sativa
(DC.) Hegi) and wild (Vitis vinifera L. subsp. sylvestris (Gmel.) Hegi)
compartments. The main objective of this study was to investigate the
level of genetic diversity obtained by the novel custom Vitis18kSNP array,
in order to analyse 71 grapevine accessions representative of wild and
cultivated Georgian germplasms. Results: The number of loci successfully
amplified was 15,317 out of 18,775 SNP and 79 % of loci resulted
polymorphic. Sixty-eight unique profiles were identified, 42 for the
sativa and 26 for the sylvestris compartment. Cluster analysis highlighted
two main groups, one for cultivars and another for wild individuals, while
a genetic structure according to accession taxonomic status and cultivar
geographical origin was revealed by multivariate analysis, differentiating
clearly the genotypes into 3 main groups, two groups including cultivars
and one for wild individuals, even though a considerable overlapping area
was observed. Conclusions: Pattern of genetic diversity structure
presented an additional proof that grapevine domestication events took
place in the Caucasian region contributing to the crop evolution. Our
results demonstrated a moderate differentiation between sativa and
sylvestris compartments, even though a connection between several samples
of both subspecies may be assumed for the occurrence of cross
hybridization events among native wild populations and the cultivated
accessions. Nevertheless, first degree relationships have not been
discovered between wild and cultivated individuals.