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稻负泥虫在山区冷凉稻田常年都有不同程度的发生为害。据在万县白士公社不同水稻品种上观察,越冬成虫先后从4月下旬、5月上旬开始转移到水稻秧苗上,继后幼虫大量发生,直至7月上、中旬水稻开始孕穗、叶片老化为止渐渐减轻,长达2月之久,成为海拔900米以上水稻的重要害虫。幼虫老熟后脱去背上粪堆结茧化蛹,成虫羽化后离开稻田。一年一代。一般秧苗期为害轻,分蘖期为害较重;杂交水稻比常规稻,叶色浓绿的粳型杂交稻“滇杂25”比叶色淡绿的“汕优2号”重。据不同防治方法试验观察,由于发生为害时间长,幼虫背上有粪堆药液不易渗透,抗药力较强,防治上常采用农业防治(合理施用氮、磷、钾肥等)为主,在卵孵期及时喷药防治相结合的方法。药剂用90％晶体敌百虫1,200—1,500倍液,间隔5—7天连续喷雾2次,可减
Paddy negative insect pests in the mountainous cold paddy perennial have varying degrees of damage. According to the observation of different rice cultivars in Wanxian Baishi Commune, the overwintering adults began to transfer to rice seedlings from late April and early May successively. Afterwards, large numbers of larvae occurred and until mid July, the booting of rice and the aging of leaves began Gradually reduce, up to 2 months long, as an important pest 900 meters above sea level rice. After the larvae mature off the back feces heap cocoon pupation, adult emergence leaves the rice fields. One generation In general, seedling stage was light and tillering stage was more serious. The hybrid rice “Dianza 25” was thicker than the light green “Shanyou No.2” than the conventional rice and dark green leaves. According to different methods of prevention and treatment of experimental observation, due to the long time of damage, larvae dredge liquid is not easy to penetrate, strong resistance, prevention and control often use agricultural control (rational use of nitrogen, phosphorus, potassium fertilizer, etc.) Incubation timely spraying combination of prevention and control methods. Pharmacy with 90% crystalline trichlorfon 1,200-1,500 times, 5-7 days interval of continuous spray 2 times, can be reduced