The research on the killing effect of insecticides mixed with synergist for Culex pipiens pallens larvae in field

Abstract

Objective To study the effect of insecticide mixed with synergist to kill Calex pipiens pal-lens larvae in field and provide a scientific and rational basis for the chemical prevention and control of mosqui-to. Methods According to WHO bioassay method and Tang Zhenhua unification drug test method, diehlor-vos, propoxur and cypermethrin were mixed with oxidation piperonyl butoxide (S1), octachlorodipropyl ether (S2) and synergy amine (MGK264) respectively, then bioassay was tested on Culex pipiens pallens larvae at 3 spots in field and the synergism coefficients were calculated. Results The synergism coefficient of dich]orves mixed with S1, S2 and MGK264 were 255.44-617.60,416.24-1 475.97 and 109.40-173.30 respectively. The synergism coefficient of propoxur mixed with S1 , S2 and MGK264 were 335.27-487.95, 329.56-948.79 and 122.08-187.23 respectively. The synergism coefficient of cypermethrin mixed with S1 , S2 and MGK264 were 304.15-471.35,232.24-252.65 and 246.95-404.40 respectively. Conclusion The obvious synergy effects were observed in the mixture of pesticides and synergist for killing of Culex pipiens pallens larvae, and the strong insecticidal effect formula can improve the effect of mosquito control. Key words: Calex pipiens pallens; Insecticide-resistance; Insecticide complex paring