Determination of Cell Wall-degrading Enzyme Activity and Pathogenicity Analysis of Rotunda Pathogens

The leaves and the pathogens （Phoma herbarum and Fusarium solani）of Rehmannia glutinosa were used as test materials,and the methods of in vitro induction culture and pathogen inoculation were used.The effects of cell wall-degrading enzyme activities of Phoma herbarum and Fusarium solani,which were pathogenic bacteria of Rehmannia glutinosa,in vitro culture and in vivo inoculation were studied,in order to provide reference for the study of the pathogenic role of cell walldegrading enzymes in the process of pathogenic bacteria infecting Rehmannia glutinosa plants.The results showed that the activities of PG and PMG were higher in the pectin-induced medium,and the Cx activity was higher in the CMC-induced medium when cultured in vitro,and the activities of PG,PMG and Cx in Phoma herbarum were higher than those in Fusarium solani.After inoculation in vivo,the maximum values of PG,PMG,Cx andβ-glucosidase activities of Phoma herbarum were higher than those of Fusarium solani,and all reached the peak on the 8th day.At this time,the PG activity was 7.83 U·mg^-1,the PMG activity was 16.00 U·mg^-1,the Cx activity was13.65U·mg^-1,and theβ-glucosidase activity was 12.01U·mg^-1.Cell wall degrading enzymes play an important role in the process of pathogenic bacteria infection.Phoma herbarum′s cell wall-degrading enzyme activity was stronger than that of Fusarium solani.PMG was secreted and acted at the early stage of infection,and the pathogenic effects of Cx andβ-glucosidase occurred at the later stage.