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一、症状:水稻从出苗到抽穗的整个生育期中全株各部位都发病。根据发病部位可分为: 1.苗瘟:一般在3叶期前,发病变黄枯死,茎基部变成黑褐色,有灰色霉层。 2.叶瘟:发生在3叶期后的秧苗和成株的叶片上。分为四类:①普通型:叶上病斑中央灰白色,周围边缘呈黄色晕圈,背面有灰色霉层。②急性型:病斑暗绿色水浸状,为椭圆型或不规则
First, the symptoms: rice from emergence to heading throughout the growth stage of all parts of the disease. According to the disease can be divided into parts: 1. Seedling blast: usually in the 3 leaf stage, the incidence of yellowing dead, the base of the stalks turned dark brown, gray mold layer. 2. Leaf blast: Occurred after 3 leaf stage seedlings and adult leaves. Divided into four categories: ① common type: the leaf spot on the central gray, around the edge of the yellow halo, the back of gray mold layer. ② acute type: spot dark green flooding, oval or irregular