Insecticides and Bioproducts against Whitefly Population and Incidence of Yellow vein mosaic virus in Okra

Synthetic chemicals and bioproducts were evaluated against white fly (Bemisia tabaci), the insect vector of Bhindi yellow vein mosaic disease. Among the chemicals, seed treatment and two sprays with imidacloprid was found most effective in reducing disease incidence by 70. 9% in 2010 and 67.9% in 2011 experiments. This treatment also reduced whitefly population by 92.9% over control. Among the bioproducts, spray of Azadirachtin at 15 days interval was the most effective in reducing disease incidence by 53 to 58% and whitefly population by 79.2%. Association of whitefly population with disease incidence indicated that 25 to 50 days after sowing was the most vulnerable stage to be attacked by virus infested whitefly vector to cause disease.