Assessment of genetic diversity among species mungo-radiata group of subgenus Ceratotropis of genus Vigna Savi. using amplified fragment length polymorphism (AFLP)

Genetic diversity, population substructure, species relationships, and gene flow was evaluated in 85 accessions belonging to the mungo-radiata group of section Ceratotropis of subgenus Ceratotropis of genus Vigna using amplified fragment length polymorphism. Twelve preselected AFLP primers generated 1869 polymorphic amplification products. The number of fragments for each primer pair ranged from 44 to 296, showing 100% polymorphism. An analysis of the mungo-radiata group from different phytogeographical regions across India revealed a high level of genetic diversity. The six species of the mungo-radiata group were assembled into three groups namely, Radiata, Mungo, and Hainiana. The highest total diversity as well as within accession diversity was obtained for the Hainiana group and minimum for the Mungo group. Genetic differentiation values for Mungo and Radiata group was 0.158 and 0.212, respectively. A high gene flow was detected within each group. For mungo-radiata-hainiana relatives, Fsc, Fct, and Fst estimates were 0.120, 0.089, and 0.034, respectively, and all Vigna species combined, the fixation indices Fst, Fsc and Fct were 0.120, 0.068, and 0.034, respectively. A tree with a star-shaped topology was obtained, in which the accessions from all the species are intermingled further substantiates gene flow between populations.