Biovars of Pseudomonas syringae pv. actinidiae Strains, the Causal Agent of Bacterial Canker of Kiwifruit, Isolated in Korea

Pseudomonas syringae pv. actinidiae is the causative agent of bacterial canker of kiwifruit. The population of this pathogen is differentiated into three biovars, biovar 1, 2 and 3, according to their molecular characteristics. In this work, we determined biovars of P. syringae pv. actinidiae strains isolated in Korea since 1997 and stored in Department of Biology, Sunchon National University, Suncheon, Korea. The biovars of P. syringae pv. actinidiae strains were determined by PCR using biovar specific primers developed previously. Of 682 strains investigated, 288 strains belonged to biovar 2, while 394 strains were biovar 3. There were no P. syringae pv. actinidiae strains belonging to biovar 1 among the strains isolated in Korea. Sudden outbreak and spreading of bacterial canker caused by biovar 3 strain suggest that this strain has character of rapid transmission