过去,人们一直认为玉米螟的防治适期在玉米心叶末期。根据我们多年的防治试验及实践,认为防治玉米螟的适期不是在心叶末期,而是在玉米的心叶中期。我县玉米心叶末期,一般在7月15～20日,而一代玉米螟开始蛀秆却在7月10日左右。若在玉米心叶末期防治,势必放过最先蛀孔的玉米螟,投药越晚,放过的越多。据调查,玉米在纳棒期折断,减产 In the past, people always thought that the control of corn borer at the end of corn heart. According to our many years of prevention and control experiments and practices, that the right to control corn borer is not in the late leaf, but in the middle of the heart of corn. My county corn heart late leaves, usually in July 15 to 20, while the first generation of corn borer began to moth but July 10 or so. If the end of the heart control of corn leaves, it is bound to let go boreholes corn borer, the more late administration, let go more. According to the survey, corn is broken in the bar during the bar, cut production