云南三带喙库蚊对DDT和溴氰菊酯的抗药性研究

Study on the Resistance of Culex tritaeniorhynchus to DDT and Deltamethrin in Yunnan Province

目的 了解云南省三带喙库蚊对DDT和拟除虫菊酯类的抗药性现状和分布。 方法 选择云南省昭通市昭阳区、德宏州芒市、普洱市江城县和孟连县，以及玉溪市元江县为调查点，采集三带喙库蚊成蚊，采用成蚊滤纸接触筒法，测定其对DDT和溴氰菊酯的敏感性，根据校正死亡率判定抗性级别。 结果 云南昭阳、芒市、江城、孟连和元江的三带喙库蚊暴露DDT 1 h，24 h后的死亡率分别为51.1%、86.8%、35.4%、21.0% 和4.6%，KT50的范围为18.76～395.65 min，除芒市为初步抗性（M）外，其余4地均为抗性（R）；对溴氰菊酯的死亡率分别为36.9%、59.2%、43.1%、34.1% 和3.3%，KT50的范围为8.69～715.37 min，各调查点均为抗性（R）。 结论 云南省从北到南的三带喙库蚊对DDT和溴氰菊酯同时存在抗性，未来在上述地区使用化学杀虫剂的策略应进行调整。

Objective To investigate the resistance level of Culex tritaeniorhynchus to DDT and deltamethrin in Yunnan Province. Methods Adult Culex tritaeniorhynchus samples were collected in Zhaoyang District of Zhaotong City， Mangshi County of Dehong Prefecture， Yuanjiang County of Yuxi City， Jiangcheng and Menglian County of Puer City. The susceptibility of Cx. tritaeniorhynchus to DDT and deltamethrin were tested by bioassay method. The resistance level was judged by adjusted mortality. Results Culex tritaeniorhynchus collected from Zhaoyang, Mangshi, Jiangcheng, Menglian, and Yuanjiang, and exposed to DDT for 1 h， the mortality after 24 hours was 51.1%, 86.8%, 35.4%, 21.0%, and 4.6%， respectively; the resistant grade in Mangshi was maybe resistance（M）， and the others 4 sites were resistance（R）. The range of KT50 to DDT was from 18.76 min to 395.65 min. The mortality of the mosquitoes from the five sites to deltamethrin was 36.9%, 59.2%, 43.1%, 34.1%, and 3.3%， respectively; the resistant grade was R in all sites， and the range of KT50 was 8.69-715.37 min. Conclusion Culex tritaeniorhynchus in Yunnan Province shows simultaneously resistant to DDT and deltamethrin, and therefore the insecticiding strategy should be adjusted.