随着保护地栽培黄瓜的面积逐年扩大,红粉病已成为大棚黄瓜栽培中的严重病害,特别在春季温度高、光照不足、通风不良的大棚里最易发生。表现为黄瓜生长后期,叶片上出现暗绿色圆形或椭圆形不规则浅褐色病斑。湿度大时,边缘呈水渍状,病斑薄,易破裂,高温时间越长,病斑上越易产生浅 With the area of ​​cultivated cucumbers expanding year by year, the powdery mildew has become a serious disease in the cultivation of greenhouse cucumbers, especially in the spring with high temperature, insufficient light and poor ventilation. The performance of the late cucumber growth, leaves appear dark green round or oval irregular light brown lesions. Humidity, the edge was water-like, thin spots, easy to rupture, the longer the high temperature, lesions more easily produce shallow