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霜霉病是保护地菠菜生产上经常发生的病害,特别是春秋两季。初发病斑在叶片正面呈淡黄色,形状不规则,大小不一,边缘也不明显,后期背面产生灰紫色霉层。病斑扩展迅速,互相连片,会使叶片变褐枯死。病害从外叶逐渐向内叶发展,从下向上蔓延,严重的整株叶片变黄枯死。种子带菌还能引起整株萎缩畸形的症状。病害一般在重茬、密植的地块或浇
Downy mildew is a disease that frequently occurs in spinach production, especially in spring and autumn. Initial lesion in the front of the leaves pale yellow, irregular shape, size, edge is not obvious, the back of the back of gray purple moldy layer. Lesions spread rapidly, connected to each other, will make brown leaves withered. Diseases gradually from the outer leaves to the development of the inner leaves, spread from the bottom up, the serious yellow leaves of the whole plant died. Seed carrier can cause symptoms of whole plant shrinkage deformity. Diseases are usually cropping, close planting plots or pouring