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近几年,黄瓜细菌性角斑病有所发展,其症状类似黄瓜霜霉病,但也有些区别。黄瓜细菌性角斑病和霜霉病的病斑,开始都呈水渍状,而且由于受叶脉限制,均呈多角形,这是相同点。但到以后角斑病的病斑中央干枯脱落,形成穿孔,而霜霉病的病斑不穿孔;另外,角斑病在叶片、果实的病斑上,常常有乳白色细菌性粘液,而霜霉病叶子上无粘液,叶背有黑色霉层。保护地的发展是造成黄瓜细菌性角斑病发病严重的主要原因。因为保护地实行轮作困难,而病菌可随病残体留在土壤中越冬,成为第二年初侵染来源。种子也可以带菌,当种子
In recent years, cucumber bacterial angular leaf disease has developed its symptoms similar to cucumber downy mildew, but there are some differences. Cucumber bacterial angular leaf spot and downy mildew lesions, began to show water-like, but also due to the limitations of the veins, were polygons, which is the same point. However, after the angular spot of disease spots central dry off, the formation of perforation, and downy mildew spot does not perforated; In addition, angular leaf spot in the leaves, fruit spots, often milky bacterial mucus, and downy mildew Disease leaves no mucus, leaf mold with black mold. The development of protected areas is the main reason for the serious incidence of bacterial angular leaf spot in cucumber. Because of the difficulties of crop rotations in the protected areas, the bacteria can stay in the soil with the disease and become the source of infection at the beginning of the second year. Seeds can also be carried as seeds