P-72. Begomoviruses: a major problem for cucurbitaceous crops in eastern Uttar Pradesh

Begomoviruses belong to family Geminiviridae are transmitted by the whitefly (Bemisia tabaci) and have a bipartite genome referred to as DNA-A and DNA-B. Begomoviruses cause a number of serious diseases of cultivated crops of the Fabaceae, Malvaceae, Solanaceae, Cucrbitaceae families. Therefore, they are considered as the major constrains for cultivation of crops like cotton, cucurbits, bean, pepper and tomato in all over the world. During our survey in rainy season of 2007 typical symptoms of yellow mosaic, leaf curling, puckering and vein bending were observed on five cultivated or non cultivated cucurbitaceous species viz. Luffa cylendrica, Luffa acutangula, Momordica charantia, Cucurbita pepo and Coccinia grandiflora growing in and around Gorakhpur and Kushinagar districts of Uttar Pradesh. The population of whiteflies (Bemisia tabaci) on these cucurbits was also noticed in the area, therefore, Begomovirus infection was suspected. The total DNA was extracted from infected as well as healthy leaf samples of these species and PCR was performed with the primers designed from the coat protein region of a Begomovirus. Electrophoresis of PCR products in 1% Agarose gel revealed successful amplification of the expected size ∼800 bp fragment from DNA of all five infected plants while no such amplicon was observed in healthy samples. These results suggest existence of Begomoviruses on Luffa cylendrica, Luffa acutangula, Momordica charantia, Cucurbita pepo and Cocinia grandiflora cucurbitaceous crops. The wide spread of Begomoviruses may be possible due to over population of whiteflies (Bemisia tabaci) feeding on cucurbitaceous crops which may be a the major problem for cultivation of these crops in eastern U.P., India.