福建甘薯薯瘟病菌致病型分布和甘薯抗病品种筛选

Distribution of different pathotypes of sweetpotato Ralstonia solanacearum and selection of disease resistant sweetpotato varieties in Fujian Province

甘薯薯瘟病是由甘薯青枯菌(Ralstonia solanacearum)引起的一种危害严重的检疫性病害.甘薯青枯菌对不同甘薯品种存在着致病力分型的现象.本研究旨在明确福建不同地区不同类型的薯瘟菌分布和现有福建培育栽培的甘薯品种的抗性情况.在2014~2017年期间,从福建10个地区采集样品,分离纯化薯瘟病菌菌株,选择31株代表性的菌株,接种新种花、金山57和湘薯75-55进行致病力分型鉴定,结果显示,在泉州洛江、连城揭乐、三明宁化采集的薯瘟菌为Ⅰ型菌;在福鼎管阳、闽侯青口、永泰嵩口、三明清流和三明永安采集的薯瘟菌为Ⅲ型菌;福鼎叠石同时发现有Ⅰ型和Ⅲ型菌;莆田灵川采集的菌株为Ⅱ型和Ⅲ型菌.经青枯菌演化型复合PCR检测,发现这31株菌株均为青枯菌演化型Ⅰ型,即亚洲分支菌株.对福建栽培的22个品种进行了Ⅲ型薯瘟菌抗性鉴定,其中3个品种(莆薯12号、金薯17和泉薯39)表现出中抗的水平.本研究结果对于抗病品种的选育以及合理布局有重要的意义.

Sweetpotato bacterial wilt caused by Ralstonia solanacearumis a severe quarantine disease.Sweetpotato Ralstonia solanacearumis a heterogeneous species complex with differences in sweetpotato varieties range.Therefore the distribution of different pathotypes of sweetpotato Ralstonia solanacearum,and the resistance of sweetpoatato varieties in Fujian Province were identified in this study.During 2014 to 2017,31 representative Ralstonia solanacearum strains were isolated from 10 districts in Fujian Province.These strains were divided into 3 types by the virulence to 3 sweetpotato varieties,Xinzhonghua,Jinshan 57 and Xiangshu 75-55.The results showed that the type Ⅰ strains were isolated from Luojiang,Jiele,Ninghua;the type Ⅲ strains were isolated from Guanyang,Qingkou,Songkou,Qingliu and Yong'an;type Ⅰ and Ⅲ strains were both found in Dieshi;type Ⅱ and Ⅲ strains were both found in Lingchuan.Phylotype multiplex PCR(Pmx-PCR)results demonstrated that all 31 strains belonged to phylotype Ⅰ(the Asiaticum division).Among the 22 sweetpotato cultivars,3 cultivars(Pushu 12,Jinshu 17 and Quanshu 39)were identified as middle resistant to type Ⅲ sweetpotato Ralstonia solanacearum.These results are beneficial to the cultivation and rational distribution of sweetpotato resistant varieties.