近年来,黄瓜细菌性角斑病发生普遍,危害严重,由于该病症状与霜霉病相似,误用药现象常有发生,从而丧失防治的有利时机,使病情失去控制,造成很大损失。 一、症状 该病主要危害叶片,也可危害茎蔓及果实,苗期至成株期均可受害。发病叶病斑扩大后因受叶脉限制而呈多角形,黄褐色,大棚、温室湿度大时,叶背面病斑产生乳白色粘液即菌脓,干后为一层白色菌膜,病斑质脆,易穿孔。而霜霉病在叶背面产生明显的紫色霉层,病斑不穿孔, In recent years, the occurrence of bacterial angular leafhopper in Cucurbitaceae is widespread and devastating. As the symptoms of the disease are similar to those of Downy Mildew, misuse of drugs often occurs, thus losing the favorable opportunity of prevention and control and losing control of the disease, resulting in great losses. First, the symptoms of the disease the main hazards leaves, but also may harm stems and fruits, seedlings to adult stage can be victimized. After the expansion of diseased leaf lesions due to restricted by the veins and polygonal, brown, greenhouses, greenhouse humidity, the back of the leaf spots milky white mucus or bacteria that pus, dry layer of white fungus, plaque brittle, Perforated. Downy mildew and the back of the mold produced a clear purple mold, the lesion is not perforated,