淡色库蚊中溴氰菊酯和生物丙烯菊酯抗性发展与击倒抗性基因频率之间的关系（英文）

DELTAMETHRIN AND ESBIOTHRIN RESISTANCE DEVELOPMENT AND THE FREQUENCY OF KNOCKDOWN RESISTANCE (KDR) ALLELE IN CULEX PIPIENS PALLENS

使用溴氰菊酯和生物丙烯菊酯对采自北京的淡色库蚊蚊株进行抗药性筛选,筛选时,4龄幼虫被置于LC 50浓度值的水体中饲养。经过7代的不间断筛选,蚊虫对溴氰菊酯和生物丙烯菊酯的抗性倍数分别上升了12.9倍和4.8倍,对应敏感株,抗性倍数分别为217.8倍和41.6倍。PCR检测结果显示,kdr抗性基因的频率在逐代上升。F 7代时,溴氰菊酯筛选株和生物丙烯菊酯筛选株的kdr抗性基因频率已分别上升至98.96%和97.87%。结果表明,Phe1014的抗性纯合子频率和抗性杂合子频率均与LC 50值之间具有显著相关性。本文证明了高浓度的拟除虫菊酯杀虫剂筛选会使Phe1014突变频率快速的上升。

A field strain of Culex pipiens pallens collected from Beijing,China was reared and used for experimental resistance selections to pyrethroid insecticides,deltamethrin and esbiothrin.Fourth instar larvae were exposed to the concentrations of LC 50 of the insecticides.After successive selections for seven generations,relative resistance increases were 12.9-fold for deltamethrin and 4.8-fold for esbiothrin,compared to the first population exposed to the insecticides.The deltamethrin-and esbiothrin-selected strains showed relative resistances of 217.8 to deltamethrin and 41.6 to esbiothrin,compared with the susceptible strains.PCR assays revealed a significant increase in knockdown resistance(kdr)allelic frequency from F 1 to F 7.The kdr allelic frequencies in F 7 generation of deltamethrin-and esbiothrin-selected populations were 98.96%and 97.87%,respectively.Strong associations were found between the frequencies of Phe1014 homozygotes,heterozygotes and the LC 50 values in the bioassays.Regression analysis also revealed a significant correlation between LC 50 value and the kdr allelic frequency.The study results demonstrate that high dose exposure of pyrethroid insecticides can rapidly increase the Phe1014 mutation frequency in Cx.pipiens pallens.