【摘要】 将敏感棉蚜用灭多威选育２０代，获得抗性倍数达１４２．３７的高抗种群，在连续数代不接触药剂的情况下，其抗性水平呈下降趋势，停药１２代后抗性基本稳定，但高于敏感种群５倍，以该种群进行恢复试验，其抗性发展速度更快，恢复８代时抗性出现突增，２０代时抗性倍数达３８３．６７。更多还原

【Abstract】 The population of highly resistance which was 142.37 folds to methomyl was produced by selected 20 generations with methomyl to susceptible cotton aphid, the population resistance declined successively when it was not treated with any insecticide for generations, but it was more than 5 folds of the susceptibe ones. The resistance selection to methomyl was conducted with its offspring, the result indicated that the speed of resistance to methomy was higher , and the resistance abrupt rised at 8 generations, and it was 383.67 folds at 20 generations.更多还原