摘要:Susceptibility levels of a lab strain of An. Stephensi to WHO standard papers of DDT 4%, dieldrin 0.4%, malathion 5%, permethrin 0.25%, lambdacyhalothrin 0.1%, cyfluthrin 0.1% and deltamethrin 0.025% were determined in our laboratory in 1999. Results showed that at the diagnostic dose of insecticides this species exhibited resistance to DDT and dieldrin with mortality rate of 54±2.5% and 30±2.5%, respectively. Malathion 5% caused 96±1% mortality. Permethrin killed 90±2% of the populations. Alpha-cyano groups of pyrethroids, e.g., deltamethrin, cyfluthrin and lambdacyhalothrin had highest efficacy, the mortality was 99.5±0.5, 100%, and 99±0.5% respectively. The results of irritability of this species to lambdacyhalothrin, permethrin cyfluthrin and deltamethrin revealed that lambdacyhalothrin had the most and deltamethrin the least irritancy effect. The average number of take offs/fly/minutes for lambdacyhalothrin and deltamethrin were 1.699±0.35 and 0.946±0.13%, respectively. For permethrin and cyfluthrin the equivalent values were 1.52±0.2 and 1.385±0.25, respectively.