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1982～1986年调查研究表明:三化螟第二代幼虫取食不同生育期水稻,其滞育率是分蘖期<拔节期<孕穗期;据测定,水稻各生育期全氮含量依次是分蘖期>拔节期>孕穗期;蚁螟取食分蘖期或孕穗期稻株后交叉接虫试验证明,稻株含氮量高低是影响幼虫滞育率的主要因素。川西由单、双季稻混栽改为一季中稻,取消了迟中稻,第二代蚁螟取食园秆至孕穗期水稻,使幼虫滞育越冬;川南单、双季稻混栽区,三化螟卵盛孵时正遇双季晚稻园秆期,对蚁螟蛀入不利;川东一季中稻区,第三代螟卵盛孵时,水稻已近黄熟,失去生存条件。营养条件的变化和不利幼虫生存的水稻生育期,是导致三化螟种群数量锐减的原因。只要品种布局合理,调节播种期,就能控制螟害。
From 1982 to 1986, the investigation showed that the second generation larvae of the rice borer fed on different growth stages of rice, the diapause rate was at tillering stage Jointing stage> booting stage; the experiment of crossing insects on the rice stems at the tillering stage or the booting stage showed that the nitrogen content in the rice plants was the main factor affecting the larval diapause rate. In western Sichuan, single-and double-cropped rice was changed to one-season middle-season rice, the late-mid-season rice was canceled, and the second-generation insecticide was fed on rice stems until the booting stage. In the mid-season rice field, the third generation of rice borer eggs Sheng Sheng, the rice has almost ripe, loss of living conditions. Changes in nutritional conditions and unfavorable larvae of rice during the growth period, is the cause of the sharp decrease in the population of three borer. As long as the variety of rational layout, adjust the sowing time, you can control the stem borer.