Kairomone effect of acetone extracts of intercrops on Chrysoperla carnea (Stephens) and Trichogramma chilonis Ishii

Onion and cluster bean, identified as cost effective intercrops in brinjal to manage major pests were selected to study the kairomone effect on Chrysoperla carnea (Stephens) and Trichogramma chilonis Ishii. Acetone extract of leaves of onion and flowers of cluster bean @ 1%) recorded the highest parasitization on the eggs of Leucinodes orbonalis (82.7 and 74.3%, respectively) by T. chilonis on seventh day after introduction of parasitoids when compared to control with acetone alone (50.3%). Similarly, acetone extract of onion leaves and cluster bean flowers were highly effective to enhance the predatory activity of C. carnea, recording 92.1 and 89.7 per cent, respectively on eggs of L. orbonalis, 24 h after introduction of the predator while it was 59.1 per cent in control with acetone alone.