近年来，随着棉花产量的提高，土壤供肥结构的变化，黄淮大部分棉区棉花红叶茎枯病都有不同程度的发生，特别是土壤中缺钾地区更易发生，个别年份大发生。发病的棉株，上部坐不住桃，中部桃子小，整个棉株吐絮不畅，轻者减产１０％左右，重则可达６０％以上。一、危害症状... In recent years, with the increase of cotton yield and the change of soil fertility structure, most of cotton fields in Huanghuai cotton bloom have varying degrees of stem blight, especially in potassium-deficient areas of soil and in some years. The incidence of cotton plants, the upper can not sit peach, the central peach small, poor cotton boll floc, the light yield reduction of about 10%, while the weight is up to 60%. First, the danger of symptoms ...