通过叶片浸药饲喂法用阿维菌素对室内敏感品系小菜蛾连续进行抗性汰选。在 2 6代选育过程中 ,从第 1代到第 4代 ,抗性指数仅仅增长 2倍多 ,第 5代出现突增 ,LD5 0值上升到 0 .0 396g/虫 ,抗性指数为 1 2 .9,第 6代抗性指数继续急速增至 2 7.8倍。从第 8代到第 1 2代 ,虽然药剂 The indoor susceptible strains of Plutella xylostella were continuously eliminated with abamectin through leaf dipping feeding method. During the 26 generations of selection, the resistance index increased by more than two folds from the first generation to the fourth generation, the fifth generation showed a sudden increase, the LD50 increased to 0.0396 g / worm, the resistance index was 1 2 .9, the 6th generation resistance index continued to rapidly increase to 2 7.8 times. From the 8th generation to the 12th generation, though the agent