用培养皿滤纸吸附测定法和不伤根土壤拌菌处理及针刺接种法 ,测定了大白菜软腐病菌游动性突变体进入大白菜体内、并在其中侵染定殖和扩展的特性。结果表明 ,游动性丧失和增强的突变体都可以通过种子萌发和主动接触进入大白菜体内、并可以在体内有短期的繁殖 ,但菌量远低于野生菌。大白菜叶片接种实验说明 ,这两种突变体也都可以进行短距离扩展 ,但扩展距离和菌的繁殖量低于野生菌。 Petri dishes were treated with filter paper adsorption assay, mixed soil without soil injury and acupuncture inoculation method to determine the mobility of Chinese cabbage soft rot disease mutants into Chinese cabbage and invaded colonization and expansion. The results showed that all the mutants with loss of mobility and enhancement could enter Chinese cabbage through seed germination and active contact, and could breed shortly in vivo with a much lower amount of bacteria than that of wild bacteria. Cabbage leaf inoculation experiments show that these two mutants can also be short-distance expansion, but the expansion distance and bacterial reproduction is lower than the wild bacteria.