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大白菜生长的中后期,常遭受软腐病、霜霉病、病毒病和黑斑病的危害,轻者植株受害。产量降低,品质变劣,严重的会导致植株死亡。对此要认真识别,及早调查,尽快防治。一、软腐病主要发生在大白菜包心期。其症状是:发病初期病株的外围叶片在中午萎蔫、早晚仍能恢复正常,以后萎蔫叶片不再恢复。严重时,病株枯黄皱缩,外叶脱落,结球小而外露,基部组织粘滑软腐,有恶臭,用脚轻踢,菜头即倒下。有
Chinese cabbage growth in the late, often suffer from soft rot, downy mildew, virus disease and black spot disease hazards, the lighter plant damage. Yield decreases, quality deteriorates, leading to serious plant death. This should be carefully identified, early investigation, as soon as possible prevention and treatment. First, soft rot mainly occurs in the cabbage heart phase. The symptoms are: the early onset of diseased leaves of the leaves in midday wilt, sooner or later still be able to return to normal after wilting leaves no longer recover. In severe cases, the diseased plants withered yellow, outer leaves fall off, the knot is small and exposed, the base of the organization sticky soft rot, stench, foot kick, the head is down. Have