Evaluation of Genetic Relationship Between Iranian and Foreign Genotypes Candidate for Rootstocks Using Microsatellite Markers

Molecular markers increase the speed and accuracy of breeding programs. The new preliminary breeding program of rootstocks is undergoing in Iran. Present research was performed to optimize conditions for breeding program and evaluation of relationship between selected rootstock candidate genotypes and some drought tolerant rootstocks. Forty seven grapevine rootstock genotypes including 3 drought tolerant rootstocks and 44 candidate genotypes were sampled and evaluated with 11 microsatellite markers. Results showed there is 21% similarity between Iranian genotypes and Riparia, 1103P and 140Ru as grapevine rootstocks. Studied Iranian genotypes were divided in to 3 main groups. The third group with 39 genotypes included three unknown genotypes of the North East region of Iran, two early ripening genotypes ‘Yaquti’ and ‘Khalili’ with 55% similarity and some other Iranian cultivars. Likelihood based assignment approach was used to determine parents of unknown genotypes. Results showed specific hetero and homozygote loci for early ripening cultivars in 3 microsatellite markers included VVMD14, VVS2 and VMC4A1. Finally, two main center of variation includes Northeast (Khorasan) and South (Fars) of Iran, were separated. It appeared that allelic diversity of Khorasan is endogenous but allelic diversity of Fars is endo and exogenous. Results showed visible effect of habitat region on genetic structure of genotypes. It is concluded that the genotypes may be used directly as drought-tolerant rootstocks or as parents to planning control crosses.