Abstract: Objective To study the effect of sublethal dose of Aedes albopictus densovirus-7 (AalDV-7) infection on the deltamethrin resistance of Ae. albopictus. Methods The laboratory resistant strain of Ae. albopictus was established by applying deltamethrin insecticide to the laboratory susceptible strain. Ae. albopictus larvae were infected with a sublethal dose of AalDV-7 (10⁸ geq/ml). The half-lethal concentration (LC₅₀) for larvae and the biological mortality of adult mosquitos in the infected and uninfected groups were determined using the resistance bioassay, and were compared by the t test and χ² test using the SPSS 19.0 software, respectively. Results The laboratory strain of Ae. albopictus resistant to deltamethrin was successfully established after 15 consecutive generations of screening. After sublethal dose of AalDV-7 infection, the LC₅₀ for larvae decreased from 0.030 0 mg/L to 0.018 5 mg/L (moderate resistance) (t=12.521, P<0.001), and the biological mortality of adult mosquitoes increased from 65.7% to 78.1% (χ²=5.079, P=0.015), with the resistance level unchanged. Conclusion Sublethal dose of AalDV-7 infection reduces the deltamethrin resistance of Ae. albopictus larvae and acts as a synergist to some extent, providing a new theoretical basis and strategy for solving mosquito resistance.

Key words: Aedes albopictus, Aedes albopictus densovirus, Deltamethrin resistance

摘要： 目的 研究白纹伊蚊浓核病毒-7（AalDV-7）亚致死剂量感染对白纹伊蚊溴氰菊酯抗药性的影响。方法 对实验室白纹伊蚊敏感品系施加溴氰菊酯进行筛选，建立抗性品系。利用亚致死剂量（10⁸ geq/ml）的AalDV-7感染白纹伊蚊幼虫，通过抗药性生物测定法检测感染组和未感染组幼蚊的半数致死浓度（LC₅₀）和成蚊死亡率，使用SPSS 19.0软件通过t检验与χ²检验分别比较幼蚊LC₅₀与成蚊死亡率。结果 经15代筛选成功建立了实验室白纹伊蚊溴氰菊酯抗性品系。亚致死剂量AalDV-7感染后，幼蚊LC₅₀由0.030 0 mg/L降低至0.018 5 mg/L（t=12.521，P<0.001），降为中等抗性，成蚊抗药性生物测定法死亡率由65.7%提高到78.1%（χ²=5.079，P=0.015），但抗性水平未变。结论 亚致死剂量AalDV-7感染可降低白纹伊蚊幼虫溴氰菊酯抗药性，在一定程度上起到了增效剂的作用，结果为解决蚊媒抗药性提供了新的理论依据与策略。

关键词: 白纹伊蚊, 白纹伊蚊浓核病毒, 溴氰菊酯抗药性