关键词: 家蝇, 溴氰菊酯, 氯氰菊酯, 抗性稳定性

Abstract: Objective To assess the stability of pyrethroids resistance in population of housefly(Musca domestica). Methods Houseflies were collected from a slaughterhouse in Chifeng of Inner Mongolia,where pyrethriod pesticides being used continuously for many years. This population was taken to laboratory to be cultured and then its resistance to cypermethrin and deltamethrin was tested. Results The results showed that:1) after selected under cypermethrin for 10 generations,the relative resistance raised to 49.96 folds,and its LD₅₀ was 1 412.75 folds of that of the sensitive population.2) attenuation of the resistance to cypermethrin in the houseflies got lower and could not resume sensitivity until F₃₀ without insecticide selection. At the same time the sample was used to do another test,the results showed that the attenuation of resistance to deltamethrin was not obvious and LD₅₀ in F₁₂ was 223.36 folds of that of the sensitive population. Conclusion The resistance to cypermethrin in housefly increased rapidly and the attenuation of resistance to cypermethrin and deltamethrin was slow.