Identification and Ecological Characteristics of Bacterial Blossom Blight Pathogen of Kiwifruit

Research in Plant Disease 2004;10(4):290-296.
Published online December 31, 2004.

참다래 꽃썩음병균의 동정 및 발생생태

신종섭¹, 박종규, 김경희, 박재영, 한효심², 정재성², 허재선³, 고영진^*

순천대학교 응용생물학과, ¹순천시농업기술센터, ²순천대학교 생물학과, ³순천대학교 환경교육과

Identification and Ecological Characteristics of Bacterial Blossom Blight Pathogen of Kiwifruit

Jong-Sup Shin1, Jong-Kyu Park, Gyoung-Hee Kim, Jae-Young Park, Hyo-Shim Han2, Jae-Sung Jung2, Jae-Seoun Hur3, Young-Jin Koh*

Department of Applied Biology, ²Department of Biology and ³Department of Environmental Education, Sunchon National University, Suncheon 540-742, Korea
¹Suncheon-si Agricultural Technology and Extension Center, Suncheon 540-804, Korea

Correspondence: Young-Jin Koh,Phone)+82-61-750-3865, Fax)+82-61-750-3208, E-mail)youngjin@sunchon.ac.kr

Received: November 02, 2004

Abstract

Bacterial blossom blight is one of the most important diseases of kiwifruit (Actinidia deliciosa). The disease occurs during flowering in the late May and disease outbreaks associated with rainfall during the flowering season have resulted in a severe reduction in kiwifruit production. The causal organism isolated from diseased blossoms of kiwifruits was identified as Pseudomonas syringae pv, syringae based on the physiological and biochemical characteristics and pathogenicity test. Dead fruit stalks, dead pruned twigs, fallen leaves and soils mainly provided P. syringae pv. syringae with overwintering places in the kiwifruit orchards, and the inocula also overwintered on buds, trunks, branches, and twigs on the kiwifruit trees. Among the overwintering places, the incula were detected in the highest frequencies from dead fruit stalks. The population density of P. syringae pv. syringae was speculated to be over 1 × 10⁴ cfu/ml for the bacterial infection, and the optimum temperature for the bacterial growth ranged 20 to 25°C. The highest population density of P. syringae pv. syringae on the overwintering places was detected in May and June when the daily average temperature coincided with the optimum temperature for bacterial growth of P. syringae pv. syringae.

Key Words: Blossom blight, Kiwifruit, Pseudomonas syringae pv. syringae