Genetic relationships of 34 grapevine varieties and construction of molecular fingerprints by SSR markers

In order to protect and promote the effective differentiation and rational utilization of grape germplasm resources, 34 grapevine varieties were selected from the National Germplasm Resources, Taigu Grape Nursery in China: 12 wine grapes (Group I), 14 table grapes (Group II) and 12 seedless grapes (Group III), 4 of which were in Group II, too. For the purpose of genetic characterization, 15 pairs of SSR (simple sequence repeat) primers were used. Sixty-six alleles were generated among Group I, including 64 polymorphic bands, with 1-8 alleles per locus. In Group II, a total of 54 alleles, from 1 to 8 (3.6 on average) alleles per locus, were identified. In Group III, 54 alleles with an average of 3.6 alleles per locus were identified and the percentage of polymorphic alleles was 94%. The 34 varieties clustered into two major clades in the dendrogram: V. vinifera with hybrid of V. vinifera and V. labrusca or hybrid of V. amurensisi and V. vinifera were clearly differentiated. After processing and filtering the raw data, we produced the molecular fingerprint code of each variety. These results showed that the SSR markers are useful for discrimination and analysis of genetic diversity of grapevine varieties. The SSR markers could be used to examine and distinguish the genetic resources among closely related varieties. This is also an effective tool for construction of a grapevine molecular fingerprinting system. The obtained data will be useful in grape breeding in the future.