关键词: 中华按蚊, 溴氰菊酯, 击倒抗性

Abstract:

Objective To investigate resistance of Anopheles sinensis to deltamethrin and its association with the kdr gene mutation in Yunnan province and parts of Henan province. Methods The An. sinensis samples were collected from Yuanyang and Mengla of Yunnan province and Tongbai, Huaibin and Yongcheng of Henan province in July and August of 2010. The standard WHO deltamethrin resistance bioassay was used to evaluate the resistance of the insects to deltamethrin by the knockdown rate and the mortality of them, and the genotype at the site 1014 Leu-Phe mutation in the kdr associated sodium channel gene was detected by polymerase chain reaction and sequencing. Results The results showed that the mortalities of An. sinensis in all the 5 regions were all lower than 98%, with death rate of less than 80% in Huaibin, Yongcheng, Tongbai and Yuanyang, where the populations were resistant. Also, elementary resistance was seen in Mengla county where the mortality was between 80%-97%. The kdr mutation was found through sequence analysis of the PCR products in the Huaibin, Yongcheng and Tongbai populations with no kdr mutation observed in the Mengla and Yuanyang populations. Conclusion There is a correlation between kdr mutation and the deltamethrin resistant phenotype in the Yongcheng and Tongbai populations, but no such a correlation has been found in the Huaibin, Mengla and Yuanyang populations.

Key words: Anopheles sinensis, Deltamethrin, Knock down resistance