在我省玉米产区三种蠕孢菌Helminthosporium引起的叶斑病中,对生产威胁最大的是大斑病H.turcicum Pass。该病在省内各地均有发生,但发病严重的主要地区是陇南及平凉地区。陇南除大斑病外,还有两种蜗孢菌叶斑病:小斑病H.maydis Nisikado & Miyake和园斑病H.carbonum Ullstrup。小斑病虽危害不重,但比较常见,园斑病很少见到,仅在个别 Among the three leaf spot blight caused by helminthosporium in the maize producing area in our province, the greatest threat to the production is the H. turcicum Pass. The disease occurred throughout the province, but the main areas of serious illness is Longnan and Pingliang area. In addition to the maculopathy in Longnan, there are two species of C. cercosporea: leaf spot H. maydis Nisikado & Miyake and garden spot H.carbonum Ullstrup. Although the small spot disease is not endangered, but more common, spotted spot rarely seen, only in individual