Molecular characterization and genetic diversity in geographical indication (GI) rice (Oryza sativa L.) cultivars of Bangladesh

Abstract

Assessment of genetic diversity and molecular characterization among elite rice cultivars of Bangladesh is important for varietal identification. Genetic diversity of 20 geographical indication (GI) rice landraces of Bangladesh was analyzed for 30 loci using simple sequence repeat markers to characterize the varieties and also to establish the sovereignty of the Bangladeshi rice gene pool. The number of alleles per locus ranged from five (RM275) to 15 (RM180), with an average of 9.7. The results revealed unique alleles that could be used for identification and molecular characterization of five landraces. The polymorphism information content (PIC) values which ranged from 0.59 (RM275) to 0.90 (RM180), with an average of 0.815, revealed much variation among the studied cultivars. The frequency of the most common allele at each locus ranged from 15 (RM85 and RM180) to 55 % (RM275 and RM277). RM180 was the best marker for identification and diversity estimation of GI rice genotypes as revealed by PIC values. A dendrogram revealed six clusters with a similarity coefficient of 0.14. Two- and three-dimensional graphical views of principal coordinate analysis showed the spatial distribution of the genotypes. The cultivars Galon, Radhunipagal, Biruin, Joina, Chamara, Horkoch, Sadamota, Topa, Kalijira, Binni, Balam, and Kataribhogh were found far away from, and distributed around, the centroid of the cluster. The findings of this study are useful for varietal identification, thus assisting plant breeders in selecting the suitable genetically diverse parents for crossing programs.