辣椒细菌性果实条斑病病原鉴定

Identification of Pathogen Causing Fruit Bacterial Streak on Pepper

【目的】研究鉴定2018年在新疆巴音郭楞蒙古自治州和硕县辣椒种植区内新发现一种辣椒细菌性果实条斑病病原,为该病田间病害规律研究和病害防治提供依据。【方法】采用组织分离法、柯赫氏法则回接证病、形态学观察、生理生化特性测定、16S rDNA分子鉴定等方法,鉴定该病病原菌,运用针刺接种法对辣椒果面进行致病性回接测定。【结果】从田间采集的发病辣椒果面上分离、纯化共获得30个单菌落;获得了4个致病性强的菌株,4个菌株形态特征及生理生化测定结果一致。4个致病菌株均与已报道的阿根廷假单胞菌Pseudomonas argentinensis聚在一个进化发育分支中,并且与模式菌株P.argentinensis CH01T(登录号:AY691188)的相似性达到99.2%。【结论】新疆和硕县辣椒细菌性果实条斑病的病原菌鉴定为P.argentinensis。

【Objective】In 2018,a new disease causing the fruit bacterial streak on pepper was discovered in the pepper planting area of Hexud County in Xinjiang.This project aims to clarify its pathogenic species,and provide basis for further research on the disease regularity in field and control the disease.【Methods】Tissue separation method,Koch's postulates,morphological observation,physiological and biochemical characteristics determination,16SrDNA gene phylogenetic analysis were used to identify the pathogen of the disease.【Results】Thirty single colonies were isolated and purified from the surface of diseased fruits collected in the pepper field.Through the pathogenicity back inoculated by acupuncture inoculation method,four pathogenic strains were obtained.They were consistent with the morphological characteristics and physiological and biochemical test results.The phylogenetic tree results showed that the four pathogenic strains were grouped into one branch:Pseudomonasargentinensis that was reported,and the similarity with the model strain P.argentinensis CH01T(accession number:AY691188)reached 99.2%.【Conclusion】The pathogen of pepper bacterial streak in Hexud County in Xinjiang was identified as P.argentinensis.