author(s)
Madhusudan S and Bhushanam M

abstract
Egg parasitoids are known to be very effective against a number of crop pests. Parasitoids belonging to the genus Trichogramma, have worldwide distribution and play an important role as natural enemies of the lepidopteran pests on a wide range of agricultural crops. But these egg parasitoids are highly susceptible to insecticides. In order to study the insecticide tolerance, the effect of the insecticides avermectin (abamectin) and a few organophosphates (chlorpyriphos, malathion, quinolphos, triazophos), oxadiazine (indoxacarb), and spinosyn (spinosad) as well as with pyrethroids (cypermethrin) on laboratory and field adult populations of the egg parasitoid Trichogramma chilonis (Hyn: Trichogrammatidae) was evaluated under laboratory conditions, using the standard tests (residue test on glass tubes) described by IOBC. When tested on the adult populations of the parasitoids chlorpyriphos, malathion, quinolphos, triazophos proved to be most lethal insecticides on the survival of the adult parasitoid. Similarly, abamectin and cypermethrin were also found to be harmful on the survival of the adult parasitoid. Indoxacarb and spinosad were found to be least harmful on the adult survival of the egg parasitoid.