Assessment of morphologic and genetic diversity of rice varieties using SSR markers associated with drought tolerance characteristics

In this study, the morphologic and genetic diversity of 32 rice varieties were studied using 15 microsatellite (SSR) markers linked to QTLs controlling drought tolerance characteristics. The total number of alleles generated by each marker ranged from 3 alleles at RM317 locus to 8 alleles at RM3, RM228 and RM231 loci. The RM317 had the highest values for effective number of alleles, Nei’s gene diversity, Shannon’s information index and polymorphic information content (PIC) among the all studied markers. The studied genotypes were classified into 3 groups based on morphological characteristics under non-stress and -4 bar stress conditions and based on molecular data. Totally, results of current research showed that there was a suitable genetic diversity between and within the different rice groups. Furthermore, reaction of the studied varieties to -4 bar stress indicated that the variety Shiroudi and the Lines 44 and 831 had the highest root length as well as the highest tolerance while the varieties Binam, Domzard and Sadri had the lowest root length and the highest sensitivity to drought stress. Among the used markers, the RM153, RM317 and RM325 markers with the most number of effective alleles as well as the highest diversity criteria were the best markers to separate the rice varieties. Therefore, these SSR markers can be utilized in marker-assisted selection programs under drought stress condition after confirmation of the obtained results in other complementary experiments.