EXISTENCE OF A NATURAL POPULATION OF TRICHOGRAMMA SPP. (HYMENOPTERA: TRICHOGRAMMATIDAE) IN SUGARCANE PLANTED NEAR AND AWAY FROM COTTON

Sugarcane (saccharum officinarum l.), is a cash crop of pakistan that is grown to meet the raw material demands of local sugar industry. insect pests of this crop, mainly the borers, causes the decline of quality and yield. among the biological pest control strategies, the parasitoids, trichogramma spp., are widely known as bio-control agent of sugarcane borers. an experimental field trial was carried out at five locations in vehari district of pakistan. the percent parasitism of 2,000 eggs of the host insect sitotroga cerealella set out on paper cards in each field by naturally occurring trichogramma spp. estimated the degree of parasitism in each field. percent parasitism of s. cerealella host eggs by trichogramma spp. in sugarcane fields was higher in fields that were isolated from cotton fields (2.7 to 16.5%) than in cane fields surrounded by cotton fields (0.0 to 5.6%). it was concluded from the present study that naturally occurring population of parasitoids, trichogramma is affected in sugarcane crop grown near cotton growing areas and this may be due to higher use of insecticides in the cotton growing areas.