Abstract:An isolate 1314 was obtained from imported Canadian pea seeds with semi-selective MT(milk tween agar) medium, and identified by PCR, 16S and 23S rRNA sequence analysis, multilocus sequence analysis (MLSA), Biolog test, hypersensitivity reaction on tobacco and pathogenicity. With the specific primer AN7F/AN7R of Pseudomonas syringae pv. pisi (Ppi), 272 bp products (100% sequence identity) were yielded with this isolate and the Ppi strain ATCC 11043, and the sequence was 99.57% identical to the Ppi isolate (X97405) in GenBank. Sequence analysis revealed that partial sequences of 16S and 23S rRNA and 16S-23S sequence of the isolate 1314 shared 100% identities with the Ppi strain ATCC 11043 in correspondence. MLSA and phylogenetic analysis were carried out with the sequences from four housekeeping genes including gap1, gltA, gyrB and ropD. The isolate 1314 was clustered with Ppi strains in the phylogenetic tree. The result of Biolog test showed that this isolate was Ppiwith the similarity (SIM) of 0.72 and probability (PROB) of 0.898.The isolate 1314 can trigger hypersensitivity reaction on tobacco by artificial injection inoculation and cause typical water-soaked symptom on the stem of inoculated young pea plant. Based on these results above, this isolate was identified as Pseudomonas syringae pv. pisi.