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一、病状及病因苗期、成株期均可发病。主要为害叶片。子叶被害初呈褪绿色黄斑,扩大后变黄褐色。真叶染病,叶缘或叶背面出现水浸状病斑,早晨尤为明显,病斑逐渐扩大,受叶脉限制,呈多角形淡褐色或黄褐色斑块,湿度大时叶背面或叶面长出灰黑色霉层,
First, the symptoms and causes Seedling stage can be morbidity. The main damage leaves. Cotyledons initially faded green macula, expanded to yellowish brown. True leaf disease, leaf margin or leaf surface appeared flooded lesions, especially in the morning, lesion gradually expanded, restricted by the veins, polygonal brown or yellowish brown patches, when humidity is large or leaves the back of the leaves grow Gray black moldy layer,