Taxonomy of Mungbean and Its Relatives

Abstract

This chapter reviews the taxonomic treatment of mungbean (Vigna radiata) and its relatives and presents photographs of key characters and a phylogenetic tree. After Tomooka et al. (2002a) listed 21 species in the subgenus Ceratotropis, six new species have been described. Phylogenetic analysis revealed the positions of two new species, Vigna indica and Vigna sahyadriana, but the remaining four new species, Vigna konkanensis, Vigna pandeyana, Vigna sathishiana, and Vigna yadavii still need to be analyzed. We transferred Vigna subramaniana from the section Ceratotropis to section Aconitifoliae. Two unidentified gene bank accessions, NI1135 and JP245506, have been referred for assessment with regard to the relationships with the new species. The gene pool for mungbean has been expanded from Tomooka et al. (2005), with special emphasis on Vigna vexillata and NI1135. Drought and salt stress studies are cited to show the importance of systematic screening for stress tolerances, which is the first step toward exploiting novel genes expected in wild relatives.