猕猴桃细菌性溃疡病菌的分离鉴定与致病性分析

Isolation,identification and pathogenicity analysis of kiwifruit bacterial canker pathogen

溃疡病是猕猴桃主要细菌性病害,其病原为丁香假单胞菌猕猴桃致病变种(Pseudomonas syringae pv.actinidiae,Psa)。文章利用不同猕猴桃种植园的溃疡病发病植株进行Psa菌株分离、鉴定及致病性分析;结果显示,获得了6个具有丁香假单胞菌形态特征的菌株,经聚合酶链式反应(polymerase chain reaction,PCR)鉴定与序列同源比对,所分离菌株为Psa,该菌株在‘红阳’猕猴桃的接种检测中显示不同致病性,其中ScYbH2、ScDjyH2、ScYbH1接种植株出现溃疡病症状,而ScMbJ1、ScDjyH3、ScYaH2未表现显著致病性。烟草叶片超敏反应也显示它们具有不同的植物免疫系统激活能力。该研究获得了猕猴桃溃疡病分离菌株,其表型差异为后续的致病基因遗传分析奠定了基础。

Kiwifruit canker is the main bacterial disease caused by Pseudomonas syringae pv.actinidiae(Psa).In this work,Psa strains were isolated and identified from diseased kiwifruit plants in different orchards for pathogenicity analysis.The results showed that six strains with P.syringae like morphological characteristics were obtained.After polymerase chain reaction(PCR)identification and sequence alignment,the isolates were identified as Psa.The inoculation of these strains in kiwifruit cultivar Hongyang exhibited their different pathogenic capabilities.ScYbH2,ScDjyH2 and ScYbH1 caused canker disease symptoms in inoculated plants,while ScMbJ1,ScDjyH3 and ScYaH2 did not possess serious pathogenicity.Moreover,the hypersensitivity reactions shown in tobacco leaves indicated different plant immunity activation elicited by the Psa isolates.In this study,isolated kiwifruit bacterial canker strains were obtained,and their phenotypic difference will provide a basis for further genetic analyses of pathogenic genes.