Molecular marker based (SSR) genetic diversity analysis in deep water rice germplasms of Bangladesh

International Journal of Biosciences 10/2012; 2(10 (2)):64-72.

ABSTRACT The study was undertaken to assess the genetic diversity among deep water rice genotypes using Simple Sequence Repeat (SSR) markers through marker aided selection (MAS). Twelve deep water rice (Oryza sativa L.) germplasms of Bangladesh was selected for genetic diversity analysis using eighteen SSR markers. Upon PCR amplification the alleles were separated on Polyacrylamide Gel Electrophoresis (PAGE) system. Initial polymorphism detection was conducted using eighteen primer pairs distributed on twelve rice chromosomes. The chosen microsatellite marker panel consisted of RM1, RM452, RM130, RM252, RM13, RM204, RM11, RM25, RM205, RM244, RM206, and RM463 with one representative from each chromosome. A total of 79 alleles were detected with an average of 4.38 alleles per locus. The polymorphism information content (PIC) reflections of alleles diversity frequency among the varieties, which is ranged from 0.477 to 0.782, with an average of 0.634. RM 13 was found as the best marker for identification of genotypes as revealed by PIC values. The Unweighted Pair Group Method with Arithmetic Mean (UPGMA) dendrogram revealed 2 major groups with 4 clusters and the wide range of dissimilarity values (0.14-0.89) which showed a high degree of diversity among the cultivars. The results of the genetic diversity will be useful for the selection of the parents for developing submergence tolerant and flash flood tolerant rice variety through molecular breeding program.

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