【摘要】 2a的试验调查表明,杂交水稻穗期三化螟的侵入以穗茎部和倒一节为主,穗部以下各节也可侵入;三化螟有转移为害习性;在大发生年,杂交水稻穗期三化螟必须防治两次,第一次防治适期应以卵孵始盛至卵孵高峰期为宜,间隔5～7d后防治第二次。更多还原

【Abstract】 The results of two years’ field experiments and investigations indicated that the infestation positions of rice yellow stem borer were majors located at ear neck and the uppermost node of rice stem. The pest larva can also enter the stem from the nodes of rice stem under the ear. It was found out the rice yellow stem borers have the behaviors of migratory infestations between plants, thus it is necessary for two chemical sprayings in the control of rice yellow stem borers. The first spraying should be targeted at the periods of between initiation hatching and the peak hatching of pest eggs, the second spraying must be taken at 5-7days afterwards.更多还原