Management of YMV through conventional breeding in mungbean

摘要

Mungbean (Vigna radiata L. Wilczek) commonly known as 'green gram' is one of the important pulse crop of India. It is an important and easily digestible cheapest source of protein to the millions of vegetarian peoples. It is cultivated during kharif,rabi and summer. It is tolerant to drought and can be grown successfully on well drained loamy to sandy loam soil in areas of erratic rainfall. In India it is the third important pulse crop after Chickpea and Pigeonpea. India is the largest producer of mungbean in the world. It accounts for 65 % of mungbean area and 54 % of world's production. It covers 3.20 million hectare with a production of 0.95 million tones and productivity 304 kg/ha (2005-06). Orissa, Maharashtra, Andhra Pradesh, Madhya Pradesh,Gujarat, Rajasthan and Bihar are the major mungbean growing states in India. Rajasthan accounts 799.5 thousand ha with a production of 130 thousand tonnes and productivity 163 kg/ha which is really very low as compared to the average productivity of thecountry. In general the productivity of mungbean is very low and unstable, primarily due to abiotic and biotic stress. As we know that in Rajasthan mungbean is a rain-fed crop mostly cultivated in light and marginal soils under high temperature which badly affects the yield. It is also true that generally the abiotic stresses are beyond our control so we have to pay attention on biotic stresses. Diseases are found to be the most important biotic stress in mungbean cultivation. The diseases like yellow mosaic virus, cercospora leaf spot, web blight and leaf crinkle are the common diseases of mung bean prevalent in Rajasthan. Among the biotic stress yellow mosaic virus (YMV) is the major disease of mungbean, transmitted through white fly (Bemisia tabaciGenn.). It causes heavy losses in grain yield and deteriorates the seed quality too. Some times it occurs in epidemic form and results in total failure of the crop. Growing disease resistant varieties is the only economic method for controlling the diseases. An ideal way of YMV disease management lies in locating a resistant source, which could be used in future breeding programme.