Abstract: Objective To investigate the resistance of Culex pipiens quinquefasciatus to common insecticides in the urban area of Shenzhen, Guangdong province, China, and to provide a scientific basis for selection of insecticides. Methods Tested Cx. pipiens quinquefasciatus mosquitoes were collected from one residential area in each of the five Shenzhen's municipal districts in 2018. The sensitive baseline method of the larval dipping method was used for resistance tests. In each test group, 5 to 7 insecticide concentrations were set, and 20 larvae were selected for each concentration. The number of dead larvae at different concentrations of insecticides was observed. SPSS 19.0 software was used to calculate median lethal dose (LC₅₀) and its 95% confidence interval, and establish the toxicity regression equation. Results The LC₅₀ of permethrin ranged from 0.148 8 to 4.456 1 mg/L, and the resistance ratio was 14.44 to 432.63. The LC₅₀ of deltamethrin ranged from 0.019 1 to 0.217 6 mg/L, and the resistance ratio was 41.25 to 469.98. The LC₅₀ of efficient cypermethrin ranged from 0.028 7 to 0.212 5 mg/L, and the resistance ratio was 35.67 to 264.14. The LC₅₀ of fenthion ranged from 0.016 7 to 0.055 9 mg/L, and the resistance ratio was 2.26 to 7.55. The LC₅₀ of temephos ranged from 0.000 5 to 0.002 6 mg/L, and the resistance ratio was 1.76 to 9.13. The LC₅₀ of propoxur ranged from 0.254 9 to 4.662 3 mg/L, and the resistance ratio was 1.25 to 22.85. Conclusion Culex pipiens quinquefasciatus in Shenzhen has developed high resistance to many pyrethroids, yet they remain susceptible and non-resistant to organophosphate and carbamate insecticides. To delay the development of insecticide resistance, it is necessary to select appropriate insecticides based on resistance monitoring results and take proper rotation treatments.

Key words: Culex pipiens quinquefasciatus, Insecticide, Insecticide resistance, Shenzhen city

摘要： 目的 了解深圳市致倦库蚊对常用杀虫剂的抗药性产生情况，为科学选择控制用药提供依据。方法 2018年在深圳市5个行政区各选择1个居民区采集致倦库蚊，使用幼虫浸渍法中的敏感基线法开展抗药性实验，每组实验设置5~7个浓度，每个浓度选取20只幼蚊，观察不同浓度的幼蚊死亡数，采用SPSS 19.0软件计算LC₅₀及其95%可信区间并建立毒力回归方程。结果 氯菊酯LC₅₀为0.148 8~4.456 1 mg/L，抗性倍数为14.44~432.63倍；溴氰菊酯LC₅₀为0.019 1~0.217 6 mg/L，抗性倍数为41.25~469.98倍；高效氯氰菊酯LC₅₀为0.028 7~0.212 5 mg/L，抗性倍数为35.67~264.14倍；倍硫磷LC₅₀为0.016 7~0.055 9 mg/L，抗性倍数为2.26~7.55倍；双硫磷LC₅₀为0.000 5~0.002 6 mg/L，抗性倍数为1.76~9.13倍；残杀威LC₅₀为0.254 9~4.662 3 mg/L，抗性倍数为1.25~22.85倍。结论 深圳市致倦库蚊对多种菊酯类药物产生较高程度抗性，对有机磷和氨基甲酸酯类杀虫剂多为敏感和低抗性。需根据抗药性监测结果选择合适的杀虫药物，采取适当的轮用措施，以延缓抗药性的发展。

关键词: 致倦库蚊, 杀虫剂, 抗药性, 深圳市