The Survey of Genetic Diversity & Population Structure Analysis of Iranian Sweet Pomegranate (Punica granatum L.) Germplasm Using SSR Markers

The pomegranate (Punica granatum L.) is native horticultural plants of Iran which have been cultivated from ancient times for its economic, ornamental and medicinal properties globally. Now Iran is one of the largest manufacturers and exporters of pomegranate in the world. Although the number of Punica species is very low, but there is a high morphological diversity have been observed within the existing varieties and genotypes in country. Therefore, the use of appropriate markers in order to separate the rich pomegranate germplasm of country is necessary. In this study, six out of 50 microsatellite markers (SSR) were polymorphic on 194 samples of the sweet pomegranate germplasm. Total numbers of observed alleles were 24, the number of alleles per locus have ranged between 2 to 8. Average polymorphism information content and heterozygosity of these primers were 0.746 and 0.778 respectively, have proved strong nature of microsatellite markers in genetic diversity studies. In order to assess of genetic relationships and population structure, Cluster analysis was performed by methods UPGMA and NJ with MEGA4 software, structure analysis modelbased Bayesian by STRUCTURE2.3 software and principal coordinate analysis (PCoA) with NTSYS software. Results of all mentioned methods have shown that cultivars and genotypes are generally clustered independently from their geographical origin and their proposed denomination suggesting that severe admixture in studied samples. Survey of our study indicated that there is a high genetic diversity among of sweet pomegranate germplasm in Iran that this result can be used for purpose of breeding.