First report of bacterial shoot blight caused by Pseudomonas syringae pv. syringae of apple (Malus pumila) in Korea.
In 2013 and 2014, a bacterial disease was observed in 20 apple orchards of northern Gyeongbuk Province (Cheongsong, Mungyeong, Yeongju, and Andong) in Korea. The initial symptoms were yellow lesions on fruit clusters and leaves. The lesions gradually expanded causing blight. Premature leaf-fall was observed on the infected trees. In some orchards, the incidence of this disease was greater than 20%. Based on biochemical, physiological, molecular (sequencing of 16S rDNA) and pathogenicity tests, the causal agent was identified as P. syringae pv. syringae. This is thought to be the first description on pathogenic P. syringae pv. syringae causing infection to apple shoots in Korea.