Plant pathogenic fungi produce cellulases.However, little information is involved in cellulase as an elicitor in plant-pathogen interaction.Here, an endocellulase (EG1) was isolated from Rhizoctonia solani.It contains a putative protein of 227 amino acids with a signal peptide and a family-45 glycosyl hydrolase domain.Its Asp residue at position 32 was changed to Ala, resulting in fully losing catalytic activity.Wild-type and mutated forms of the endoglucanase were expressed in yeast and purified to homogeneity.The purified wild-type and mutant forms induced cell death in maize, tobacco and Arabidopsis leaves, and transcription of three defense-marker genes in maize and tobacco and 10 genes related to defense responses in maize.Moreover, they also induced accumulation of reactive oxygen species (ROS), medium alkalinization, Ca2 + accumulation and ethylene biosynthesis of suspension-cultured tobacco cells.Similarly, production of the EG1 wild-type and mutated forms in tobacco induced cell death using the PVX expression system.In vivo, expression of the EG1 was also related to cell death during infection of maize by R.solani.These results provide direct evidence that the endoglucanase was an elicitor but its enzymatic activity was not required for its elicitor activity.