Study On Physiological Biochemical Indexes At Resistance Of Chinese Cabbges To Soft Rot

This study adopted Chinese Cabbage varieties with different resistens, and determined relation of soft rot bacteria content in petiole and Peroxidase activity, Polphenol oxiclase activity,celllulase activity, sucrase activity, cellulose content and the variration of soluble sugar content , at the same time, including determining the variaration of six physiological biochemical indexes around inoculation in seedling time .And through making a correlated analysis of disease resistance and the variaration of six physiological biochemical indexes around inoculation in seedling time, established the resistance physiological mechanism.In development of different resistance Chinese Cabbage, bacteria content in petiole is different, batteria content of susceptible cultivavs increase with growing time prolonged , but resistant cultivars do not change basically.Peroxidase, polphenol oxidase, cellulase, sucrase, cellulose and soluble sugar are closely related with Chinese Cabbage resistance to soft rot. Effect of Peroxidase in resistance mechaisem of Chinese Cabbage mainly expressed in middle-later of growing time. Effect of polphenol oxidase ,cellulase resistance mechanism mainly expressed in sedling time. Effect of sucrase in resistance mechanism mainly expressed in the whole growing time. Effect of cellulose and soluble sugar content in resistance mechanism mainly expressed in the whole seedling time.In seeding time, resistant cultivars of Chinese Cabbage inoculated with softrot bacteria after a week, peroxidase activity increased, remarkably, while activity of polphenol oxidase, cellulase, sucrase decreased, cellulose content increased remarkably,soluble sugar content has no obvius change;but the expression of susceptible cultivars is opposite or did not change obviously.The correlation of Chinese Cabbage soft rot resistance and the increasing range of cellulase activity in 2 true leaves time, soluble sugar content after inoculated 3 weekes attained extremly remarkable. This correlation can be regarded as the biochemical indexes of determining the soft rot resistance of different Chinese Cabbage varieties or experimental materials. This study initially established the regulation of determining the soft rot resistance of Chinese Cabbage in seedling time.