截形叶螨（Tetranychus truncatus Ehara）是我国玉米生产上的一种重要的害螨。目前对截形叶螨的防治主要依赖化学农药。本研究通过室内浸液法测定截形叶螨成螨、若螨对3种不同作用机制的杀螨剂乙唑螨腈、联苯肼酯和螺螨酯的敏感性。结果表明，乙唑螨腈的毒力最强，对雌成螨和若螨24 h的LC₅₀分别为0.033 mg/L、0.070 mg/L；联苯肼酯的毒力最低，对雌成螨和若螨24 h的LC₅₀分别为0.685 mg/L、0.210 mg/L。3种杀螨剂对产卵量的影响均显著。乙唑螨腈可作为田间防治截形叶螨的最佳备选药剂。

Tetranychus truncatus is one of the most serious pests on maize. To date, control of this pest has been mainly relying on spraying of chemical pesticides. In this study, we compared the susceptibility of T. truncatues nymph and adult to three acaricides, namely SYP-9625, Bifenazate and Spirodiclofen. The results showed that SYP-9625 performed the highest toxicity to either nymph or adult of T. truncatus, with the LC₅₀ values(24 h) of 0.033 mg/L and 0.070 mg/L, respectively. Bifenazate displayed the lowest toxicity, with the LC₅₀ values(24 h) of 0.685 mg/L and 0.210 mg/L for nymph and adults, respectively. All of the three acaricides had significant effects on reproduction of T. truncatus. In conclusion, the results have valuable significance for practical management of T. truncatus in the field.

国家重点研发计划“北方玉米化肥农药减施技术集成研究与示范”（2017YFD0201802）