ABSTRACT
The grape (Vitis vinifera L.) cultivars in the island of Crete, Greece represent one of the oldest populations of the species; nevertheless, very scarce information is available about its genetic structure. In this study, Vitis cultivars collected from the island of Crete were characterized using microsatellite markers. A broad germplasm collection representing 44 inferred Vitis cultivars, a total of 163 accessions, from the area of Crete including 37 wine and 7 table cultivars were fingerprinted employing thirteen (13) standardized simple sequence repeat (SSR, microsatellite) loci. SSR allelic analysis and a similarity dendrogram construction (cluster analysis) was followed by a hierarchical STRUCTURE analysis. The mean observed (Ho) and expected heterozygosity (He) were 0.7372 and 0.7686, respectively. The cumulative probability of identity was very low with a value of 3.18 × 10e-15. According to the cluster analysis, twenty-nine of the 44 Vitis cultivars were presented in single clusters and five cultivars were presented as distinct single accessions. In addition, ten (10) cases of synonyms and ten (10) groups of homonyms were also identified. STRUCTURE analysis provided evidence for three genetic groups (putative ancestry groups). Hierarchical STRUCTURE analysis revealed further stratification within each of the three ancestry groups. This work provides the molecular fingerprinting of 44 Vitis cultivars and an initial proposal in their ancestry. In the future, molecular genetic information along with morphological (ampelographic) data will provide an intergraded characterization of existing diversity and will allow for its use in breeding efforts and in commercial viticulture.
