EFFECTIVENESS OF SOME CONTROL OPTIONS AGAINST THE INSECT PESTS OF WHEAT AND THEIR NATURAL ENEMIES

Abstract

An experiment was conducted to evaluate the effectiveness of sonic control options against the insect pests of wheat and their natural enemies during the period from November. 2012 to Marc!). 2013 at the central thrm of Sher-e-Bangla Agricultural L:niversity, Dhaka. Bangladesh. The experiment consists of six management practices such as: 1,: Cultural control (weeding) at 10 days interval, i2: Mechanical control (handpieking of infested tiller) at 7 days interval: 13: Cultural control + Mechanical control at 7 days interval: 14: Spraying of Suntap 50 SP @3.0 gm/f. of water at 7 days interval -t Mechanical control; 1 5: Spraying of Marshal @3.0 nil/I. of water at 7 days interval - Cultural control + Mechanical control at 7 days interval; T6:Spraying olNeern oil 3.0 nil! 10 1. of vater at 7 days interval + Cultural control -I- Mechanical control at 7 days interval and 17: Untreated control. The experiment was laid out in Randomii.ed Complete Block Design (RCI3D) with three replications. Incidence of major insect pest of wheat was recorded as aphid. wireworm. stem fly and army worm. Incidence of natural enemies were also recorded as lady bird beetle, parasitic wasps (parasitoid). svrphid liv and spider. At tillering stage, the lowest infested plants were observed from T (1.37%) treatment, on the other hand, the highest infested plant was recorded in 17 (1 3.23%) untreated control treatment At panicle initiation stage, the lowest infested plants were observed from Ti(1 .75%) treatment. but the highest infested plants were recorded in 17 (1 5.6O%) untreated control treatment. Finally, during grain filling stage. the lowest infested plants were observed from i 5 (2.49%) treatment, whereas the highest infested plants were recorded in 17 (18.77%) untreated control treatment. The longest plant was measured from T5 (92.80 cm) treatment. while the shortest plant was obtained from 17( 77.56 cm) untreated control treatment. 'Ihe highest yield was recorded from T (3.43 t/ha) treatment, while the lowest yield was obtained from T7 (2.14 t/ha) untreated control treatments. Spraying of Marshal @ 3.0 nil/I, of water at 7 days interval - Cultural control + Mechanical control at 7 days interval showed superior br controlling wheat insect pests.