Genetic diversity of the mungbean (Vigna radiata, Leguminosae) genepool on the basis of microsatellite analysis

Abstract

A large representative collection of mungbean (Vigna radiata (L.) Wilczek) consisting of 415 cultivated, 189 wild and 11 intermediate accessions was analysed by using 19 SSR primers. These SSR primers showed polymorphism in wild and cultivated mungbean and were selected from those available for the related species azuki bean [V. angularis (Willd.) Ohwi & Ohwi]. One or more SSR primer for each linkage group (on the basis of the azuki linkage map) was analysed. In total, 309 alleles were detected and of these, about twice as many were detected in wild (257 alleles) as in cultivated accessions (138 alleles). The results show that Australia and New Guinea represent a distinct centre of diversity for wild mungbean. Cultivated mungbean has greatest diversity in South Asia, which supports the view that South Asia is where this crop was domesticated. SSR marker allelic diversity for cultivated mungbean has distinct regional variation, with high variation in South and West Asia. The present study represents the first comprehensive analysis of wild and cultivated mungbean germplasm diversity by SSR markers, and highlights specific genetic diversity that might be used to broaden the genetic base of currently grown mungbean cultivars.