西洋参枯萎病病原分离与鉴定

Isolation and Identification of American Ginseng Fusarium Wilt Pathogen

旨在对引起西洋参枯萎病的病原进行分离与鉴定,以期为大田生产中该病害的防治提供理论依据。在陕西留坝县和太白县西洋参产区发现一种西洋参新型病害——西洋参枯萎病,症状主要表现为参根维管束呈黄色,病叶黄化萎蔫,后期叶片干枯不脱落。依据Koch’s准则证明分离物YL002是引起该病害的病原菌。对YL002菌株的rDNA-ITS、TEF1-α及RPB1基因片段进行PCR扩增和测序,采用形态学并结合分子生物学鉴定结果表明,该病害的致病病原菌为尖孢镰刀菌(Fusarium oxysporum)。该研究为国内关于西洋参枯萎病的首次报道。

The aim of this study was to isolate and identify the pathogen causing American ginsengFusarium wilt,in order to provide a theoretical basis for the disease control in field production.Fusarium wilt,a new disease of P.quinquefolius,was discovered on the American ginseng in Liuba countyand Taibai county in Shaanxi of China.The diseased plants exhibited main symptoms such as yellowing leaves,withered plants,and yellow vascular tissue.According to conduct the Koch's postulates,YL002 isolated from the diseased ginseng was proved to be the pathogen of the Fusarium wilt.The fragments of rDNA-ITS,TEF1-α,and RPB1 gene were amplified and sequenced.The strainwas identified as Fusarium oxys porum based on morphological characteristics and DNA-based molecular identifications.To our knowledge,this is the first report about Fusarium wilt of P.quinquefolius in China.