Legumes, which are major source of dietary proteins, minerals and vitamins, are grown world over. In India and Southeast Asia, among Vigna spp. grown as grain legumes during July to October – Kharif season, black gram (Vigna mungo L. Hepper) and green gram (Vigna radiata L.) Wilczek) are more important ones. The production of these two major kharif pulses is adversely affected by most destructive YMD, which was first reported by Nariani (1960. Whitefly-transmitted bipartite begomoviruses named as Mungbean Yellow Mosaic India Virus (MYMIV), Mungbean Yellow Mosaic Virus (MYMV), Horsegram Yellow Mosaic Virus (HgYMV) and Dolichus Yellow Mosaic Virus (DoYMV) are four distinct etiological agents of this disease in legume crops in India and other South Asian countries.
Disease incidence and severity as high as 100 per cent in farmers’ fields is common, often resulting in considerable yield losses in green gram and black gram in India and in Pakistan. The disease has been recorded since long back on green gram and black gram in Jharkhand, India too, but the etiological agent is not identified so far. There is enough literature that refers resistant genotypes of green gram and black gram against YMD but without identifying the etiological agent. Since three distinct viruses i.e. MYMIV, MYMV and HgYMV are reported to cause YMD in Vigna spp., accurate identification of the virus is important.