Eleven genotypes of forty-four isolates were obtained in analysis of 23S rDNA PCR-RFLP. There were 2 genetic groups at 83% similarity level. Thirty-seven strains of group 1 were separated with reference strains and they have the elven genotypes.

• 23S rDNA PCR RFLP聚类树状图中看出,所有供试菌株在大约83%25的相似水平上聚成2个遗传群,其中群1包括37株菌,有11种遗传型;