Objective: To screen out the potentially pathogenic endophytic fungi from 18 strains of endophytic fungi isolated from roots of Salvia miltiorrhiza

in order to explore the pathogenic mechanism of these fungi. Method: The plant-endophyte symbotic experiment was conducted to choose the potential pathogens. To determine pathogenic fungi

the changes in the activities of cell wall degrading enzymes

including cellulose [carboxymethyl cellulose enzyme(Cx)

β-glucosidase(β-G)]

pectinase[polygalacturonase(PG)

polymethylgalacturonase(PMG)] and xylanase enzymes were measured in vitro and in vivo. Result: In vitro

all of the 9 strains could secrete cell wall degrading enzymes (CWDE)

including cellulose

pectinase and xylanase. Cx and β-G activities increased over time

while PG

PMG and xylanase activities first increased and then decreased. In vivo

all of the 9 strains could secrete cell wall degrading enzymes in the roots of Salvia miltiorrhiza

but with differences among them. Roots of inoculations of 7 strains showed increase in Cx and β-G activities

roots of inoculations of 6 strains showed increase in PG activity

while roots of inoculations of 9 strains showed higher PMG and xylanase activities. Conclusion: Cellulase and pectinase and xylanase play important roles as pathogenic factors

but with differences in actions of potentially pathogenic endophytic fungi.