Abstract: A resistant strain selected successively in the laboratory for 17 generations had 198.63 fold resistance to methamidophos. The resistant levels and fitness of offsprings from the resistant strain and susceptible strain or field population were closer to those of the resistant strain than those of the susceptible strain or field population. It showed that the changes of the resistant levels of the hybrid progeny were propitious to the resistance development, and the changes of the fitness went against the resistance development by contraries. The effects of the migration on the development of methamidophos resistance in Nilaparvata lugens were discussed in the aspects of the migration of brown planthopper, the resistant levels of offsprings and the changes of the fitness.

Key words: Nilaparvata lugens, hybridism, resistance, fitness

摘要： 通过室内筛选得到了对甲胺磷具有极高水平抗性的抗性品系（抗性倍数198.63）。利用该抗性品系与敏感品系、田间种群杂交，杂交子代的抗性水平都明显地倾向于抗性品系，表明杂交子代的抗性水平有利于本地抗性的发展。通过建立实验种群生命表，发现与敏感品系和田间种群相比，抗性品系及其与敏感品系、田间种群杂交子代的生物适合度都有显著下降，表明抗性品系及其杂交子代种群增长具有很大的不利性，从而减少了抗性虫源数量，有利于本地敏感性的回复。从褐飞虱迁飞、杂交子代抗药性及生物适合度变化的角度，讨论了迁飞扩散对褐飞虱的甲胺磷抗性发展的影响。

关键词: 褐飞虱, 杂交, 抗药性, 适合度