心叶末期防治玉米螟效果佳巴东县大支坪乡夏家超玉米进入心叶末期，也就是大喇叭口期，是防治玉米螟的关键时期。因为玉米到了心叶末期，玉米螟全部集中在叶丛中进行危害，为用药提供了有利条件，既能提高防治效果，又能降低生产成本。怎样确定玉米的心叶末期呢？方法是：... The end of the heart of leaf prevention and control of corn borer effect Jiabadong County, Tai Ping Ping Xia summer home into the heart of the late leaf, that is, the big bell mouth stage, is the key to the prevention and control of corn borer. Because the end of corn leaves to the end of the heart, corn borer all concentrated in the leaves of the hazards for the medication provided favorable conditions, both to improve the control effect, but also reduce production costs. How to determine the end of the heart of corn it? the way is:...