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甘蓝黑腐病是甘蓝生产中的一种常发病,一般减产在10—20%,严重时可达40%以上,是甘蓝生产的一大障碍。(1)症状识别该病主要发生在叶片,叶球或茎球。幼苗期发病,子叶和心叶呈水浸状,后迅速变黑枯萎。成株期发病,以老叶发病较多,病叶发黄。病菌由水孔侵入时,可引起叶缘发病,形成“V”字形病斑;从伤口侵入时,可在叶部任何部位形成不定形的淡褐色病斑,边缘常有黄色晕圈,病斑向两侧或内部扩展;致周围叶肉变黄或枯死。病菌进入茎部维管束后,可逐渐蔓延到珠茎部或叶
Black cabbage black rot is a common disease in the production of cabbage, the general reduced production of 10-20%, severe up to 40% or more, is a major obstacle to the production of cabbage. (1) Symptoms Identification The disease occurs mainly in leaves, leaf bulb or stem ball. Seedling incidence, cotyledons and heart leaves were flooded, quickly after dark wither. Adult onset, the incidence of old leaves more, diseased leaves yellow. Pathogen invaded by the water hole can cause leaf edge disease, the formation of “V ” shaped lesions; invaded from the wound, can be formed in any part of the leaf amorphous brown spot, the edge often yellow halo, Lesions spread to both sides or inside; cause yellowing or withering of the surrounding mesophyll. After the bacteria enter the vascular bundle, they can gradually spread to the stems or leaves