桔梗叶斑病病原细菌的鉴定

Pathogen identification of bacterial leaf spot of Platycodon grandiflorum

20 0 0～ 2 0 0 1年在江苏、浙江、安徽等地发现一种桔梗病害 ,并从其病叶上分离得到了 2 6个菌株。菌株接种于桔梗叶片后 ,发病症状与自然发病症状完全一致 ,并从回接病株上重新分离得到此病原菌。各菌株间致病力无明显的差异。经革兰氏染色反应、菌体形态、培养性状、生理生化反应、 (G +C) %等鉴定 ,确定该病原菌为丁香假单胞杆菌的一个新的致病变种。该病菌能引起桔梗细菌性叶斑病 (又称斑点病 )。

A new bacterial disease,bacterial leaf spot in balloon flower root,was first found in Jiangsu,Zhejiang and Anhui during 2000? 2001.Twenty six strains were isolated from the diseased leaves of balloon flower root.Inoculation on balloon flower root seedings with the strains produced the same symptom as infected plants.All 26 isolates were identified as a new pathogenic pathovar of Pseudomonas syringae on Platycodon grandiflorum by pathogenicity,strain reactions,morphological characterization,culturing pattern,physiological and biochemical reactions,and(G+C)%.The name of the new pathovar was designated as Pseudomonas syringae pv. platycodon pv.nov.