Abstract: This experiment studied the yellow-rot disease of pleurtus ostreatus. Two main strains of bacterial were isolated from cultivation plates (G1 and G2). By resumption infection experiment, it was found that the fruting bodieds of G1 are in accord with natural infection fruiting bodies. So, it is believed that G1 is the main pathogen of yellow-rot disease. Finally, this pathogen strain was identified as Pseudomonas fluorescens by traditional physiological-biochemical experiments, 16s rDNA analysis and the Biolog microbial identification system.

Key words: classification and identification , resumption infection, Pseudomonas fluorescens, pleurtus ostreatus yellow-rot disease