Cross species amplification of Adzuki Bean derived microsatellite markers in Asian Vigna species

The Vigna is one of the important genus of grain legumes which forms the source of dietary protein and seven species of this genus, are domesticated as food crops in Asia. In recent years, molecular marker technology has greatly accelerated breeding programs for the improvement of various crops. Among the different DNA markers, microsatellite or simple sequence repeats (SSRs) are the markers of choice for various genetic studies due to their co-dominant nature, loci specificity and high reproducibility. To date, only few reports are available on isolation and development of microsatellite markers in some of the Vigna species. Therefore, the available SSR markers from other Vigna species should be validated for their transferability and utility in those species in which they are unavailable. In the present study, a set of 40 microsatellite primers pairs derived from adzuki bean (Vigna angularis) were used to assess the transferability and tested for their ability to amplify microsatellite loci in different species of Asian Vigna. The materials for this study included eleven different genotypes belonging to seven species of Asian Vigna such as V. mungo var silvestris, V. mungo, V.umbellata, V. trilobata, V. aconitifolia, V. radiata var sublobata and V. radiata. All the 40 SSR primer pairs showed cross species amplification and produced a total of 158 alleles in the genotypes studied. The percentage of amplification varied for each species which ranged from 37.5% (V.trilobata-2) to 100% (V. mungo var silvestris and V.mungo), while others showed more than 50% amplification. Apart from amplification, sufficient levels of polymorphism were also observed between cultivated blackgram and greengram and their progenitors V. mungo var silvestris and V. radiata var sublobata respectively. These findings suggest that microsatellite markers from adzuki bean could be used in genomic studies of other Vigna species and thus aid in their improvement.