小菜蛾对溴氰菊酯抗性选育及其机理

STUDIES ON DELTAMETHRIN RESISTANCE BREEDING AND ITS RESISTANT MECHANISM OF DIAMOND BACK MOTH

本研究用溴氰菊酯在室内以点滴法处理小菜蛾4龄幼虫,连续继代药剂淘汰选育其抗药性,至F_(65)代,抗药性提高到1163倍,已形成高抗性品系。其抗性的形成发展趋势为前期相对缓慢,中期较快,后期迅速增长。于1992、1993、1994年分别以氯氰菊酯、敌敌畏、杀虫双、灭多威等杀虫剂测定该抗性品系选育过程中不同抗性程度时的敏感度,结果表明它对菊酯类杀虫剂有明显的正交互抗性,对其它非菊酯类杀虫剂没有产生交互抗性。用聚丙烯酰胺凝胶电泳法(PAGE)测定表明,小菜蛾对溴氰菊酯抗性的产生可能与非特异性酯酶同工酶的活性提高有关。羧酸酯酶(CarE)、乙酰胆碱酯酶(AChE)以及多功能氧化酶(MFO)的活性测定结果显示:小菜蛾对溴氰菊酯的抗性与羧酸酯酶和乙酰胆碱酯酶无关,而与多功能氧化酶有着密切关系,它是该抗性的重要因子。

Diamond back moth(Plutella xylostella L. ) larvae in fourth instar were topically applied with deltamethrin in successive generations in the laboratory to develop resistant strain of this pest. After 65 generations, the resistance of this pest to deltamethrin increased by 1163-fold. The resistance development in this selected strain was slow in the earlier stage, faster in the mid-stage, and rapid in the later stage. The sensitivities of the deltamethrin resistant strain to cypermethrin, DDVP, dimehypo and methomyl were tested in 1992, 1993 and 1994. The results showed that the deltamethrin resistant strain had very marked positive cross-resistance to pyrethroid and had little positive cross-resistance to the other insecticides. PAGE demonstrated that the resistance to deltamethrin might be related to the higher activity of some non-special esterases. The results of study on activity of CarE, AChE and MFC) showed that the resistance of the moth to deltamethrin were not related to CarE and AChE, but the resistance was related to MFO, and it was an important factor to the resistance.