Abstract
The study was conducted during 2013 on spring sown crop, which remained in the field from March to September using brinjal variety Nirala. The Experiment was laid out in a Split Plot Design with three replications having insecticides as main plot factor and application interval as a sub plot factor. Two insecticides, Tracer (spinosad) and Timer (emamectin benzoate) were applied at three application intervals using a knapsack hand operated sprayer. All plots were sprayed uniformly on May 01 for the first insecticide application. Subsequent sprays were done at 4, 8 and 12 days after first application (DAFA). All the marketable fruit was plucked 1 day before first insecticide application. Infested and healthy fruit was separated and counted. For subsequent sprays, marketable fruit washarvested in the morning and spray applied in the evening of same day. Number and weight of healthy and infested fruit was recorded. Benefit cost ratio (BCR) was calculated to evaluate the economics of insecticide application at different intervals.