Molecular markers and their application for DNA fingerprinting and genetic diversity studies in some Bangladeshi Aus Rice (Oryza Sativa) Genotypes

Abstract

The allelic diversity and relationship among 120 Aus rice landraces were determined through DNA fingerprinting using microsatellite (SSR) markers. A total of 85 SSR markers were used to characterize and discriminate all tested Aus rice genotypes, 45 of which were polymorphic for different chromosome numbers. The number of alleles per locus generated by each marker varied from 6 alleles (RM484 and RM541) to 30 alleles (RM519) with an average of 13 alleles per locus. The polymorphic information content (PIC) values varied widely among loci and ranged from 0.5211 (RM536) to 0.9369 (RM519) with an average 0.8217. The highest PIC value (0.9369) was obtained for RM519 followed by RM286 (0.9357). The genetic distance-based results seen in the unrooted neighbor-joining tree clustering reveal nine genetic groups. Aus genotypes of BRRI released modern varieties were clustered in the same group. Being grouped into distant clusters and highest genetic distance, eleven genotypes viz. Atithi dhan, Kadar chap, Pankiraj, Japanese#7, Jamri saity, Logi jota, Joba, Lada moni, Manik Mondal-2, Boilum and Brmulka-2 could be selected as potential parents for crop  improvement for their distinctive characters. Panchash and Parija had closest distance in the SSR based CS-Chord distance (0.000) might have same genetic background. Genetic dissimilarity co-efficient was recognized between every two genotypes based on DNA profile. The highest genetic dissimilarity (1.000) was found among the nineteen Aus genotypes combinations followed by the second highest (0.9778) ninety four Aus rice combinations. Whereas lowest genetic dissimilarity was found Kala and Kalo Hizli (0.1778) followed by Holat and Holae (0.2667). This information will provide maximum selection of diverse parents, background selection during backcross breeding programs and assist in broadening germplasm-based rice breeding programs in the near future. 

words: Aus rice, Genetic diversity, Microsatellite markers, DNA fingerprinting