淡色库蚊DDVP抗性选育及交互抗性的实验研究

目的探讨淡色库蚊DDVP抗性选育后抗性发展状况以及对3种化学杀虫剂的交互抗性，为合理使用杀虫剂提供依据。方法采用WHO标准生物测试法计算Lc50，回归方程和抗性指数。结果经过43代的选育，抗DDVP品系的抗性达12．17倍，在21代时，对DDVP、残杀威、氯氰菊酯、溴氰菊酯的抗性倍数分别是6．55、4．16、43．27、0．70倍；到第30代时，分别是8．17、4．74、52．48、0．75倍；到39代时，对DDVP的抗性为10．37倍，对残杀威、氯氰菊酯的抗性分别为6．96倍、160．43倍。结论长期使用一种杀虫剂易产生抗性，亦对其他杀虫剂产生交互抗性，用药时应注意种类的选择。

The tentative study on resistance selection and cross-reslstance of DDVP-resistant Culex Pipiens Pallens

Objective To explore the resistance selection and cross-resistance of DDVP-resistant Culex pipiens palllens to four commonly used insecticides for mosquito control by their rational use. Methods WHO standard bioassay was employed to calculate LC50, regression equation and resistance index. Results The resistance index of DDVP-resistant Culex pipiens pallens increased to 12.17 times after the 43th generation＇s selection. The indexes of the resistant mosquito to DDVP, propoxur, cypermethrin, and dehamethrin were 9.54, 2.68, 7.00, 1.74, 1.70 times in the 21st generation and 11.34, 2.85, 8.07, 2.00, 1.80 times in the 30th generation, respectively. In the 39th generation, those were 11.78 times to propoxur, 3.35 times to DDVP and 9.71 times to eypermethrin. Conclusion The resistance and cross-resistance were easily developed for a long term use of one kind of insecticide, which showed that the insecticides should be rationally used in mosquito control to delay the development of the resistance and cross-resistance.