甲胺磷对稻纵卷叶螟及其天敌的影响

实验室、田间试验表明 ,甲胺磷对稻纵卷叶螟及其寄生蜂、捕食性天敌等均有不同程度的杀伤作用。各代推迟喷药、放宽防治指标可提高纵卷叶螟幼虫被寄生率 ,对产量并无影响。结合前期施药对褐飞虱再增猖獗的促进作用 ,建议在水稻生长前期谨慎用药 ,尤其应限制甚至禁止在稻田使用甲胺磷。

Effects of methamidophos to Cnaphalocrocis medinalis (Guenee) and its natural enemies on rice

Experiments carried out both in laboratory and field indicated that application and timing of methamidophos had significant harmful effect not only on the rice leaffolder Cnaphalocrocis medinalis (Guenee) but also on its natural enemies, such as parasitoids, predatory spiders and Paederus fuscipes. Injury level of rice by the leaffolder could be reduced only within a couple of weeks after spray, and there was no significant difference among the yields of different treatments. Intentionally delayed application of insecticides and increase of action threshold for controlling leaffolder of different generation increased larvae parasitism and had no significant effect on their yields. Because of the stimulation of resurgence of the brown planthopper by spraying drugs in early time, it is recommended that insecticides should be applied judiciously in the early stage, and particularly, the high toxic methamidophos must be banned.