广西玉林西番莲果腐病病原菌的分离与鉴定

Isolation and Identification of Pathogen Causing Passion Fruit Rot in Yulin,Guangxi

2020年4月,广西玉林市一个西番莲种植区发生了严重的果腐病,发病率约为20%,严重影响了果实的产量和质量。为明确该果腐病的病原种类,采用组织分离法获得3株菌株,通过观测其致病性、形态学特征和分子生物学特性对3株菌株进行鉴定。致病性测定结果显示,分离出的3株菌株均可引起西番莲果实腐烂,症状与田间病株相似。菌落特征及分生孢子形态特征符合交链格孢(Alternaria alternata)的分类特征。进一步通过ITS基因序列分析,分离菌株序列与模式菌株CBS 479.90 A.alternata的同源性为100%。因此鉴定引起广西玉林市西番莲果腐病的病原为交链格孢A.alternata。本研究是交链格孢(A.alternata)引起广西玉林市西番莲果腐病在国内的首次报道。

In April 2020,a serious fruit rot occurred in a passion fruit(Passiflora edulis)planting area in Yulin,Guangxi,with an incidence of about 20%,which seriously affected the yield and quality of fruit.In order to identify the pathogen of fruit rot,three strains were obtained by tissue isolation and identified by pathogenicity,morphological and molecular biological characteristics.The results of pathogenicity test showed that all the isolated strains could cause fruit rot of P.edulis,and the symptoms were similar to those of the field.The characteristics of colony and conidia of the strains were consistent with those of the description of Alternaria alternata.The sequences of the ITS showed 100%similarity to the type strain CBS 479.90(A.alternata).Therefore,the pathogen of passion fruit rot was identified as A.alternata.This is the first report of A.alternata causing passion fruit rot in Yulin,Guangxi.