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目的 通过案例报道和详细文献解析评估蚊虫对生物化学杀虫剂烯虫酯抗药性和交叉抗药性的风险,并建议抗药性治理的策略和方法.方法 将于美国加利福尼亚南部观察到的携带低水平烯虫酯抗药性的致倦库蚊在实验室暴露于70％ ～90％死亡率的选择压力下达30代,每隔两代进行1次生物测定,并与实验室敏感品系和未选择品系进行比较,以便确定抗药性的升高趋势.结果 由于现场产品使用所导致的低水平烯虫酯抗药性在实验室70％ ～90％死亡率下选择30代后显著升高,与实验室敏感品系相比抗药性的LC50水平达到了1 167.3倍,LC90水平达到了421.7倍,而与未选择品系相比抗药性的LC50水平达到了168.3倍,LC90水平达到了57.4倍.结论 虽然烯虫酯和其他保幼激素类似物曾经被认为没有抗药性风险,本案例的发生,加上为数不多的先前发表的关于其他蚊种的文献足以证明烯虫酯抗药性,甚至因此发生的与其他杀虫剂的交叉抗药性的风险的确存在.因此,在产品使用过程中动态监测蚊虫种群的敏感性是非常必要的.本文对于烯虫酯抗药性以及由此而致的交叉抗药性进行了讨论分析.“,”Objective To assess the risk of resistance to methoprene and resulted cross-resistance to other pesticides in mosquitoes through case report and analytical literature review and suggest the strategy and methods to combat resistance development.Methods A field collection of the southern house mosquito Culex quinquefasciatus that carried low-level resistance to s-methoprene was subjected to laboratory selection at 70％-90％ mortality for 30 generations.Bioassays were conducted every 3rd generation concurrently with a susceptible laboratory colony and unselected population to monitor the resistance development.Results The low-level resistance due to product application in the field reached to a significantly high level in response to further laboratory exposure for 30 generations,amounting to 1 167.3-fold at IE50 and 421.7-fold at IE90 as compared with susceptible laboratory colony,and 168.3-fold at LC50 and 57.4-fold at LC90 in relation to unselected population.Conclusion It was once believed that methoprene and other juvenile hormone analogs would negate the potential of resistance evolution owing to their unique mode of action.The reported occurrence,doubled with few earlier studies on other species,truly indicated the risk of resistance even cross-resistance,which warrants the needs of susceptibility monitoring before,during and after applications of methoprene products in the field.Resistance to methoprene and resulted cross-resistance to other pesticides were discussed.