玉米螟在张家口地区一年发生两代,分布普遍,为害严重。虽经连年越冬防治,处理玉米秸杆比较彻底;玉米心叶末期防治一代也很普遍,但是两代螟害无明显减轻趋势,春玉米被害株率心叶期约30—50％,穗期可达50—90％。为此1977—1979年我们从寄主植物角度研究各代玉米螟发生的虫源,进一 Corn borer occurred in Zhangjiakou area two generations a year, widespread, serious damage. Although the winter overwintering prevention and treatment, more complete treatment of corn stalks; corn leaf late prevention and control generation is also very common, but the two generations of pests did not reduce the trend, the rate of spring corn damaged leaves about 30-50% Up to 50-90%. For this reason, from 1977 to 1979, we studied the origin of each generation of corn borer from the perspective of host plants,