FIELD EVALUATION OF DIFFERENT INSECTICIDES AGAINST WHEAT APHIDS AND THEIR NATURAL ENEMIES IN PAKISTAN

Abstract

Nine insecticides were evaluated against three wheat aphid species (Rhopalosiphum padi L., Schizaphis graminum Rond. and Sitobion avenae F.) and their Coccinellid predators at recommended field doses under field conditions during wheat growing season 2012-13. The insecticides were malathion (Malathion®), carbosulfan (Advantage®), imidacloprid (Confidor®), thiamethoxam (Actara®), pymetrozine (Plenum®), aliphatic hydrocarbons+mineral oil (Diver®), azadirachtin+salannin (Neemosal®), mineral oil (Foliol®), bifenthrin (Talstar®) at recommended field doses, i.e.,1235 ml, 1235 ml, 198 ml, 60gm, 988, 494 ml, 2470 ml, 4940 ml and 618 ml, respectively. Malathion, bifenthrin and thiamethoxam effectively reduced the population of S. graminum while bifenthrin and imidacloprid were more effective against S. avenae. All the insecticides were more effective against R. padi than for S. graminum and S. avenae. However, bifenthrin, malathion, imidacloprid, thiamethoxam, pymetrozine and carbosulfan significantly lowered the population of R. padi. Aliphatic hydrocarbons+mineral oil, azadirachtin+salannin and mineral oil could not significantly lower the population of S. graminum and S. avenae. Imidacloprid proved to be effective against all aphid species yet it was the safest against coccinellids. Thiamethoxam showed the maximum decrease in coccinellid populations followed by malathion, pymetrozine and carbosulfan.