广西香蕉枯萎病病原菌4号生理小种的分子检测与鉴定

目的]明确在广西个别香蕉产区发现的香蕉枯萎病病原种类,为防控该病害提供科学依据.方法]从广西不同香蕉产区采集香蕉枯萎病病株样本,分离纯化获得6株菌株,以香蕉枯萎病1号和4号生理小种为阳性对照,采用特异PCR的方法,对分离到的6株菌株进行分子检测,并用盆栽香蕉和西贡蕉小苗接种进行菌株致病性鉴定.结果]经ST1/ST2特异引物扩增,1号菌株与香蕉枯萎病菌1号生理小种扩增到约200 bp片段;2~6号菌株和香蕉枯萎病菌4号生理小种扩增到约250 bp片段.与标样对比结果表明,1号菌株为香蕉枯萎病1号生理小种,2~6号菌株为香蕉枯萎病4号生理小种;盆栽接种致病性鉴定结果与分子检测结果相同.结论]广西个别蕉区已遭受香蕉枯萎病菌4号小种侵染,各级部门应高度重视.

Detection and identification of banana Fusarium wilt pathogen(FOC4) in Guangxi

Objective]The purpose of the present research was to determine pathogen kinds of banana Fusarium wilt,discovered in some banana growing areas of Guangxi,and to provide scientific references for preventing and controlling banana Fusarium wilt.Method]Six strains,purified and isolated from banana Fusarium wilt samples collected in different banana growing areas,were detected by specific PCR method;moreover,pot experiment was conducted for pathogenic identification using tissue cultured banana and Xigong banana seedling as test plants.Result]After ST1/ST2 specific primer amplification,No.1 strain obtained 200 bp segment,which was the same as that of the FOC race 1(positive control),and No.2 to 6 strains got 250 bp,which was the same result as that of the FOC race 4(positive control).Compared with the standard specimen,No.1 strain was FOC race 1 and the No.2 to 6 strains were FOC race 4.Therefore the pathogenic identification result of pot inoculation was in accordance with the molecular detection result.Conclusion]It was testified that FOC race 4 infection had spread in some banana growing areas of Guangxi,and relevant departments should pay close attention to this problem.