Pigeonpea (Cajanus cajan (L.) Millsp) is often cross pollinated (20-70%) crop with diploid chromosome no. 2n=2x=22, and genome size 858 Mb. It is second most important pulse crop grown in India after chickpea having 20-25 per cent protein which is nutritionally, complementary to cereals in its pattern and profile of amino acids. Sterility mosaic disease (SMD), a major constraint to pigeonpea production, was first described in 1931 from Bihar State, India and subsequently from several states of India and from Bangladesh, Nepal, Thailand, Myanmar, and Sri lanka. SMD is responsible for yield loss of worth >US $300 million (Jones et al. 2004). SMD is caused by Pigeonpea sterility mosaic virus (PPSMV) which is transmitted by eriophyid mites (Aceria cajani Channabasavanna).