Molecular characterization of mulberry genotypes and species in Turkey

Mulberries are one of the most important traditional fruit in Turkey and either consumed fresh or processed into several traditional products. Mulberry trees (genotypes) belong to Morus alba L., Morus nigra L., and Morus rubra L. shows high phenotypic diversity. In this study, 26 genotypes of Morus nigra, 21 genotypes of Morus rubra and 26 genotypes and landraces of Morus alba sampled from different parts of eastern Anatolia region in Turkey were fingerprinted using 16 simple sequence repeat (SSR) markers. Among SSR markers, the number of alleles per locus ranged from 2 (SS01, SS05) to 11 (MulSTR3) with an average of 5.19. A total of 83 alleles were obtained for the 16 SSR markers. The polymorphic information content ranged from 0.43 to 0.84 with an average of 0.61 per locus. In this study, MulSTR3, MulSTR5, MulSTR6, SS04 and SS20 were found to be the most useful SSR markers to detect genetic differences between mulberry species, genotypes and landraces. Genetic similarity ratio ranged from 0.24 to 0.94 with a mean similarity value of 0.41 indicating a high level of polymorphism among the mulberry species, genotypes and landraces. Clustering based on Jaccard's similarity coefficient and an unweighted pair group method with arithmetic mean (UPGMA) revealed 3 main clusters that corresponded with species. The results of the present study indicate that white mulberry landraces and genotypes were more diverse than the red and black mulberry genotypes. Therefore, white mulberry genotypes can be a good source for the mulberry-breeding programme due to its better genetic diversity as well as its high economical and yield properties.