Genetic structure and diversity analysis in Vitis vinifera L. cultivars from Iran using SSR markers

A broad germplasm collection of 1.5. ha containing most of the Iranian grape cultivars including 31 table grape, 22 juice grape, 6 table grape, raisin, 2 table grape, raisin, wine and one table grape, wine were analyzed using 23 simple sequence repeat (SSR) loci. The number of alleles obtained ranged from 2(VVS3) to 15 (VMCNG2G7) with an average of 8.65 alleles/locus, and the effective number of alleles differed from 1.82 (VrZAG83) to 9.73 (VMCNG2G7) with a mean value of 4.41. Considering the high degree of polymorphism, five SSR markers including VMCNG2G7, VVMD5, VVMD8, VVS2 and VrZAG64 with PIC values greater than 0.80 were selected for rapid fingerprinting of many grape genotypes. The observed heterozygosity varied between 0.49 (VVMD17) and 0.97 (VrZAG64), without significant differences from the expected values considering all the loci analyzed. Based on likelihood ratios two possible parent-offspring relations were determined and pedigrees illustrating the relationship between these varieties were reconstructed. The integration of the obtained results with ampelographic data allow to univocally identify the Iranian cultivars and could become a significant tool for the certification of quality grapes produced in specific regions. The phenetic relationships depicted by Neighbor-Joining analyses of SSR data were congruent and, to a large extent, in agreement with the known pedigree or history of each cultivar. Usefulness of this SSR set for characterization of an Iranian grapevine collection is emphasized, as well as the elaboration of databases with these molecular markers.