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黄瓜霜霉病是黄瓜生产上的重要病害,露地及保护地栽培的黄瓜都会普遍发生,尤以大棚黄瓜受害损失较重。此病发病率高,传播速度快,如条件适宜,短期内就可使全棚瓜秧枯黄,严重影响黄瓜产量。1.发生特点黄瓜霜霉病是由藻状菌纲引起的真菌性病害,主要为害叶片。苗期子叶感病后,初时病部退绿,逐渐现出不规则病斑,潮湿时,子叶背面病斑长出灰
Cucumber downy mildew is an important disease in cucumber production, open field and protected cucumber cultivation will be common, especially in greenhouse cucumber damage suffered heavy. The incidence of the disease is high, the spread of fast, such as suitable conditions, short-term can make the whole shed melon seedlings yellow, seriously affecting the yield of cucumber. 1. Occurrences Cucumber downy mildew is a fungal disease caused by algae fungi, the main damage to the leaves. After the seedling leaves a sense of disease, early retreat green part of the disease, and gradually showed irregular lesions, moist, cotyledon back lesions grow gray