Abstract: Objective To investigate the resistance levels of Blattella germanica in Wuhu, Anhui Province, China, so as to provide a scientific basis for rational insecticide use.Methods From March to June 2022, test B. germanica cockroaches were collected from restaurants, bakeries, hotels, supermarkets, and farmers' markets in Yijiang, Jinghu, Sanshan, and Jiujiang districts of Wuhu. The resistance of B. germanica to 12 commonly used insecticides was determined using the residual film method. SPSS 22.0 was used for data processing and analysis.Results The 24 h mortality rates of B. germanica treated with permethrin, tetramethrin, cypermethrin, deltamethrin, alpha-cypermethrin, beta-cypermethrin, lambda-cyhalothrin, propoxur, azamethiphos, acephate, dichlorvos, and chlorpyrifos were 91.20%, 18.40%, 91.33%, 89.47%, 77.85%, 92.62%, 99.19%, 100%, 96.85%, 100%, 76.06%, and 99.00%, respectively. The median knockdown time (KT₅₀) was 32.63, 900.61, 28.17, 30.47, 26.60, 11.06, 16.54, 17.93, 14.13, 59.66, 27.57, and 38.21 min, respectively. According to the resistance criteria by mortality, B. germanica in Wuhu was sensitive to lambda-cyhalothrin, propoxur, azamethiphos, acephate, and chlorpyrifos; potentially resistant to permethrin, cypermethrin, deltamethrin, and beta-cypermethrin; and resistant to tetramethrin, alpha-cypermethrin, and dichlorvos. Based on the knockdown resistance criteria, B. germanica in Wuhu was sensitive to azamethiphos; lowly resistant to beta-cypermethrin, lambda-cyhalothrin, propoxur, acephate, and chlorpyrifos, with the resistance ratios being 2.58, 3.21, 1.39, 2.01, and 1.41, respectively; moderately resistant to permethrin, cypermethrin, deltamethrin, alpha-cypermethrin, and dichlorvos, with the resistance ratios being 6.54, 6.39, 7.79, 5.58, and 7.14, respectively; and extremely high resistant to tetramethrin, with the resistance ratio being 259.54. KT₅₀ or 24 h mortality had no significant correlation with insecticide consumption (r_{KT50-inseciticide consumption}=0.045, r_{24 h mortality-insecticide consumption}=0.141, all P>0.05).Conclusions B. germanica in Wuhu has developed medium or high resistance to a variety of insecticides. In cockroach control, the use of insecticides should be regulated according to the results of resistance monitoring to delay the development of resistance.

Key words: Blattella germanica, Residual film method, Insecticide, Insecticide resistance, Wuhu

摘要： 目的了解安徽省芜湖市德国小蠊的抗药性水平,为合理用药提供科学依据。方法2022年3－6月,在芜湖市弋江、镜湖、三山和鸠江区的餐饮店、面包店、宾馆、超市和农贸市场等生境采集试虫,采用药膜法对12种常用杀虫剂进行抗药性生物测定。运用SPSS 22.0软件对数据进行处理和相关性分析。结果芜湖市德国小蠊对氯菊酯、胺菊酯、氯氰菊酯、溴氰菊酯、顺式氯氰菊酯、高效氯氰菊酯、高效氯氟氰菊酯、残杀威、甲基吡恶磷、乙酰甲胺磷、敌敌畏和毒死蜱的24 h死亡率,分别为91.20%、18.40%、91.33%、89.47%、77.85%、92.62%、99.19%、100%、96.85%、100%、76.06%和99.00%,半数击倒时间（KT₅₀）分别为32.63、900.61、28.17、30.47、26.60、11.06、16.54、17.93、14.13、59.66、27.57和38.21 min。依照死亡率抗性标准,芜湖市德国小蠊对高效氯氟氰菊酯、残杀威、甲基吡恶磷、乙酰甲胺磷、毒死蜱为敏感种群,对氯菊酯、氯氰菊酯、溴氰菊酯、高效氯氰菊酯为可能抗性种群,对胺菊酯、顺式氯氰菊酯和敌敌畏为抗性种群。依照击倒抗性标准,芜湖市德国小蠊对甲基吡恶磷敏感；对高效氯氰菊酯、高效氯氟氰菊酯、残杀威、乙酰甲胺磷、毒死蜱为低度抗性,分别为2.58、3.21、1.39、2.01和1.41倍；对氯菊酯、氯氰菊酯、溴氰菊酯、顺式氯氰菊酯及敌敌畏为中度抗性,分别为6.54、6.39、7.79、5.58和7.14倍；对胺菊酯为极高度抗性（259.54倍）。KT₅₀、24 h死亡率与杀虫剂用量间无相关关系（r_{KT50-杀虫剂使用量}=0.045,r_{24 h死亡率-杀虫剂使用量}=0.141,均P>0.05）。结论芜湖市德国小蠊对多种杀虫剂产生中、高度抗性,在蜚蠊防制中应结合抗药性监测结果,规范杀虫剂使用,以延缓抗药性的发展。

关键词: 德国小蠊, 药膜法, 杀虫剂, 抗药性, 芜湖市