Status of the major aphid-transmitted viruses of pulse crops in India

Pests and diseases pose significant threat in cultivation of pulse crops worldwide. There are several factors for lower productivity of pulses of which biotic and abiotic stresses are very important. Among the biotic stresses, plant viruses cause significant yield losses in pulse crops worldwide including India. Altogether 168 plant virus species under 39 genera are reported to infect grain legumes in nature. Aphid-transmitted plant viruses are considered of great significance as majority of them are seed-borne in nature. Aphid-transmitted viruses responsible for considerable yield losses in pulse crops belong to the genera, Potyvirus, Alfamovirus, Luteovirus, Cucumovirus, Enamovirus, Nanovirusand Polerovirus and they have word wide distribution. Of these, important ones infecting pulses in India are bean common mosaic virus (BCMV), pea seed-borne mosaic virus (PSbMV), bean yellow mosaic virus (BYMV), bean leaf roll virus (BLRV), chickpea stunt disease associated virus (CpSDaV), cowpea aphid borne mosaic virus (CABMV), alfalfa mosaic virus (AMV) and cucumber mosaic virus (CMV). Incidences of aphid-transmitted viruses have been recorded from time to time from various parts of India. BCMV has been reported from almost all of the major pulses growing regions of India with seed-transmission rate as high as 83%. Bean common mosaic necrosis virus (BCMNV) was not reported earlier but recently it has been reported from India to cause severe damage in common bean. Current taxonomic position, virion properties, incidence, yield loss, transmission and symptomatology of the major the aphid-transmitted viruses infecting pulses in India have been compiled.