Abstract:To understand the overwintering ablility of Xanthomonas axonopodis pv. phaseoli and X.fuscans subsp.fuscans causing common bacterial blight of common bean in soil and common bean plant debris, the pathogens were detected and identified in 20 soil samples and 14 plant debris samples collected from 18 common bean production fields in Heilongjiang, Inner Mongolia, Shanxi, Hebei and Xinjiang. The results showed that typical Xanthomonad-like bacteria were detected in extracts of 12 soil samples and 13 debris samples on MT selective medium. The pathogenicity of the representative isolates was confirmed by stem inoculation of young bean plants, 27 out of 29 isolates were pathogenic on bean cultivar "Yingguohong". The genomic DNA of representative isolates were amplified with the X.axonopodis pv. phaseoli and X.fuscans subsp.fuscans specific primer pair X4c/X4e and X.fuscans subsp.fuscans specific primer pair Xf1/Xf2 in a multiplex PCR, and 17 isolates were identified as X.axonopodis pv. phaseoli,while 10 isolates were X.fuscans subsp. fuscans. The study showed the pathogens of common bacterial blight can overwinter in soil and crop residues in the some bean production regions of Heilongjiang, Inner Mongolia, Shanxi and Hebei.