Erwinia pyrifoliae,a Causal Endemic Pathogen of Shoot Blight of Asian Pear Tree in Korea

Shrestha, Resemary; Koo, Jun Hak; Park, Duck Hwan; Hwang, In Gyu; Hur, Jang Hyun; Lim, Chun Keun

The Plant Pathology Journal 2003;19(6):294-300.
Published online December 31, 2003.

Erwinia pyrifoliae,a Causal Endemic Pathogen of Shoot Blight of Asian Pear Tree in Korea

Resemary Shrestha, Jun Hak Koo, Duck Hwan Park, In Gyu Hwang, Jang Hyun Hur, Chun Keun Lim

Abstract

Bacterial strains were isolated from diseased samples of shoot blight collected from different pear growing orchards of Chuncheon, Korea from 1995 to 1998. Forty-nine strains showed their pathogenicity on immature fruit and shoot of pear. Microbiological, physiological, and biochemical tests were performed on these pathogenic strains. One strain, designated as WT3 in this study, was selected as a representative strain as it was collected from the first outbreak area in Jichonri, Chuncheon in 1995. Further detailed characterization of the strain WT3 was done by PCR amplification using specific primers described previously for distinguishing Erwinia pyrifoliae from its close pathogen Erwinia amylovora. Based on phenotypical, biochemical, and molecular analyses, strain WT3 was identified as a shoot blight pathogen which was the same as E. pyrifoliae Ep16 previously described by a German group in 1999.

Key Words: fire blight, Hwankum, necrogens, phytopathogens, plasmid profiles