棉花红叶茎枯病是一种生理性病害。近几年在曲周县发生比较严重,在盛铃期叶片脱落或整株枯死,幼铃脱落,成铃铃重下降,衣分降低,不能正常吐絮。据调查,一般棉田病株率达5—10%,重病地块达20—30%,最高达40%以上,严重影响了棉花的生产。一、发病症状红叶茎枯病在棉花盛铃期以后开始发生,发病初期上中层叶片呈暗绿色,以后叶片变厚,皱缩发脆,叶脉间出现黄色斑点,叶脉仍为绿色,叶 Cotton leaf blight is a physiological disease. In recent years, Quzhou County occurred more serious in the Shengling period leaves or dead whole plant, young bell off, into a bell weight loss, lower clothing, not normal bolting floc. According to the survey, the general cotton plant disease rate of 5-10%, 20-30% of severely ill land, up to 40% or more, seriously affecting the cotton production. First, the incidence of symptoms Red stem blight occurred after the cotton boll period, the early onset of the middle leaves were dark green, thickening after the leaves, shrinkage crisp, yellow spots between the veins, veins are still green, leaves