一、分布及危害:十字花科蔬菜根肿病分布较广,从南到北各地产区均有发生。该病在苗期即可发生,根部肿大,地上部分生长不良,最后根部腐烂,全株枯萎死亡。二、症状特征:发病初期病株生长迟缓,植株矮小,主根或侧根肿大,通常呈纺缍形、手指形或不规则形,大小不等,大的像小红薯,小的像小饭豆,一般发生在主根上的肿瘤大,发生在侧根上的较小,数量不等。病根初期表面光滑,后期龟裂、粗糙,极易遭受其他病菌 First, the distribution and damage: cruciferous vegetables clubroot disease is widely distributed, from south to north all the production areas have occurred. The disease can occur in the seedling stage, the root swelling, poor growth on the ground, the final root rot, the whole plant withered death. Second, the symptoms and signs: early onset of disease growth retardation, plant dwarf, main root or lateral enlargement, usually spiraled-shaped, finger-shaped or irregular shape, size, big like small sweet potatoes, small like small beans , Generally occur in the main root of the tumor, occurred in the lateral root of the smaller, the number varies. Sick root early smooth, late cracking, rough, vulnerable to other bacteria