Effect of Propoxur and Synergists for Controlling Culex pipiens pallens

Objective To enhance the killing effect of propoxur against Culex pipiens pallens,collected from Tengzhou,Taian and Jining cities in Shandong Province.Method WHO standard bioassay method was employed to calculate LC50,regression equation and synergistic coefficients.Result The synergistic coefficients of propoxur mixed with S1(piperonyl butoxode),S2(octachlorodipropyl ether) and MGK-264 were 2.23-8.02,2.19-9.49 and 1.06-2.44,respectively,showing good synergism.Conclusion After Culex pipiens pallens yields resistance to propoxur,the mixture with synergists may provide better efficacy to control the mosquito.