Resistance of Tetranychus viennensis to insecticides in apple orchards in Shaanxi Province
Author of the article:PENG Li-Juan** ZUO Ya-Yun Duan Xin-Le CHEN Mao-Hua
Author's Workplace：College of Plant Protection, Northwest A&F University, Key Laboratory of Crop Pest Integrated Pest Management onthe Loess Plateau of Ministry of Agriculture, Yangling 712100, China
Key Words：Tetranychus viennensis, toxicity, insecticide resistance monitoring, apple orchard
Abstract： [Objectives] To investigate insecticide resistance in Tetranychus viennensis (Zacher) in apple orchards in Shaanxi Province. [Methods] The slide-dip method was used to test the toxicity of five insecticides to a susceptible population of T. viennensis, and to specimens from eight wild populations collected from apple orchards at Qianxian, Liquan, Xingping, Chengcheng, Ansai, Chunhua, Fengxiang and Fufeng, Shaanxi Province. [Results] The susceptible population was the most sensitive to abamectin, and the least sensitive to chlorpyrifos. The eight wild populations had moderate to high resistance to pyridaben (resistance ratios of 13.29-69.63), and low to high resistance to lambda-cyhalothrin (resistance ratios of 7.99-46.74), and were susceptible, or had low levels of resistance, to abamectin (resistance ratios of 1.89-7.63). The Fufeng population was slightly resistant to chlorpyrifos but all other populations were susceptible to this pesticide, and all populations were susceptible to thiamethoxam. [Conclusion] The susceptible population of T. viennensis showed different sensitivity to the five insecticides tested. Field populations varied in their resistance to pyridaben and lambda-cyhalothrin, and were susceptible, or had low levels of resistance, to abamectin, chlorpyrifos and thiamethoxam. These results suggest that the application of pyridaben and lambda-cyhalothrin should be reduced, and rotation of insecticides should be considered to manage the development of insecticide resistance in T. viennensis.