Effect of azadirachtin based formulation (econeem) on the natural enemies of Helicoverpa armigera (hubner) - A pest of cotton

The laboratory experiments were conducted to determine the safety level of Econeem to predator, Chrysoperla carnea (Stephens) and parasitoid, Trichogramma chilonis Ishii. Econeem was found to be safer to predator at 20.45 ppm as it did not cause mortality of larvae of C. carnea when fed with treated eggs of host Helicoverpa armigera (Hubner). The remaining dosages viz., 130.16 and 1130.91 ppm of Econeem caused 9.33 and 18.00 per cent mortality of larvae, respectively. Predator when fed with treated larvae of host caused 8.67, 10.67, 28.67 per cent mortality of larvae of C. carnea at 130.05, 303.33 and 724.54 ppm of Econeem, respectively. Econeem at 130.05 ppm was safe to predator as contaminated honey solution when fed to adults did not cause mortality of predator. At 303.33 and 724.54 ppm of Econeem, mortality levels of predatory adults were 17.33 and 38.67 per cent, respectively. Mortality of adults of T. chilonis was 1.33, 4.00 and 13.33 per cent in 130.05, 303.33 and 724.54 ppm of Econeem, respectively. The adult emergence of T. chilonis got affected when parasitised host eggs were treated with Econeem at 130.05 (84.33%), 303.33 (82.88%) and 724.54 ppm (77.77%) concentration.