半夏枯斑病病原鉴定

Identification of the Pathogen of Pinellia ternata Blight

目的:明确半夏枯斑病的病原菌种类及其分类学地位。方法:采用组织分离法进行病原菌的分离鉴定,采用柯赫氏法则验证病原菌的致病性,采用形态学鉴定结合多基因系统发育分析,明确病原菌分类学地位。结果:采用组织分离法,从半夏发病植株中分离得到5株菌株,依据柯赫氏法则验证菌株BXHM-1和BXHM-2能够引起半夏叶片发病。基于ITS序列、Tub-2和TEF基因序列进行多基因序列系统发育分析,菌株BXHM-1和BXHM-2与已报道的马铃薯坏疽病菌Boeremia exigua聚集在同一进化分支上。综合形态学和分子生物学鉴定结果,将贵州省赫章县新发现的半夏枯斑病病原鉴定为Boeremia exigua。结论:首次报道Boeremia exigua引起半夏叶部病害,本研究为该病害的防治奠定了基础。

Objective:To identify the species and taxonomic status of pathogenic bacteria of Pinellia ternata blight.Methods:Patho-genic bacteria were isolated and identified by tissue separation method,the pathogenicity of pathogenic bacteria was verified by Koch′s rule,and the taxonomic status of pathogenic bacteria was determined by morphological identification combined with multi-gene phyloge-netic analysis.Results:Five strains were isolated from the disease plant of Pinellia ternata by tissue separation,and BXHM-1 and BX-HM-2 were proved to cause Pinellia ternata leaf disease according to Koch′s rule.Based on the multi-gene phylogenetic analysis of ITS,Tub-2 and TEF gene sequences,strains BXHM-1 and BXHM-2 clustered on the same evolutionary cladism as the reported potato gan-grene bacterium Boeremia exigua.Based on the morphological and molecular identification results,the blight pathogen of Pinellia ternata in Hezhang county,was identified as Boeremia exigua Guizhou province.Conclusion:The Pinellia ternata leaf disease caused by Boere-mia exigua is reported for the first time.This study provides basic research for the prevention and control of this disease.