Pathogenic variation and molecular characterization of Fusarium species isolated from wilted sesame in China
Pathogenic variation and molecular characterization of Fusarium species isolated from wilted sesame in China
复制标题
中国枯萎芝麻镰孢菌的致病变异及分子特征
DOI：
10.5897/ajmr11.1081
复制
发表时间：
2012-01-09
影响因子：
--
通讯作者：
Zhang Xiu-rong
中科院分区：
文献类型：
--
作者：
Li Dong-hua;Wang Lin-hai;Zhang Xiu-rong
从萎蔫芝麻（Sesamum indicum L.）来自中国22个地区的25个农场。这些被鉴定为尖孢镰刀菌（20个分离株）和其他镰刀菌属。通过聚合酶链反应和真菌核糖体RNA基因的内部转录间隔区的测序，对5个分离物进行了鉴定。镰刀菌分离株的分子特征进行基因组DNA扩增片段长度多态性（AFLP）分析。25株分离物可分为两型（Ⅰ型为F.尖孢镰刀菌和其他镰刀菌属的II型）。以芝麻品种3433为试材，测定了25个菌株的致病力。不同镰刀菌菌株引起的病害严重程度不同，有5个镰刀菌菌株引起的病害严重程度不同。尖孢菌分离物（02、08、11、20和25）对芝麻的毒力较强。将AFLP分析结果与致病力数据进行相关性分析，发现I型可分为2个亚型：IA型，致病力为中至弱，IB型，致病力为强。这些结果为芝麻抗病育种提供了重要依据。
关键词：芝麻， 枯萎病，尖孢镰刀菌，AFLP，致病性
Twenty-five isolates of Fusarium species were obtained from wilted sesame (Sesamum indicum L.) grown on 25 farms from 22 regions of China. These were identified as Fusarium oxysporum (20 isolates) and other Fusarium spp. (5 isolates) by polymerase chain reaction and sequencing of the internal transcribed spacer region of fungal ribosomal RNA genes. Molecular characterization of Fusarium isolates was performed using amplified fragment length polymorphism (AFLP) analysis of genomic DNA. The 25 isolates were grouped into two types (type I for F. oxysporum and type II for other Fusarium spp.). The pathogenicity of the 25 isolates was tested on sesame cultivar 3433. And the Fusarium isolates varied in the degree of disease severity they caused; with five F. oxysporum isolates (02, 08, 11, 20, and 25) were having more aggressive virulence to sesame than the other isolates. The results of AFLP analysis were combined with the pathogenicity data to conduct correlation analysis, and it was found that type I could be divided into 2 subtypes: type IA, with middle to weak pathogenicity, and type IB, with strong pathogenicity. These findings are an important foundation for sesame resistance breeding.
Key words: Sesamum indicum L., Fusarium wilt, Fusarium oxysporum, amplified fragment length polymorphism (AFLP), pathogenicity.