香蕉枯萎病菌4个生理小种核糖体DNA内转录间隔区的RFLP分析

【目的】明确香蕉枯萎病菌Fusarium oxysporum f.sp.cubense 4个生理小种的系统发育关系。【方法】利用PCR扩增该病菌4个生理小种的核糖体DNA内转录间隔区(Internal transcribed spacer,ITS),利用AIu I、Hpa II和Taq I 3种限制性内切酶对这些小种的ITS产物进行RFLP分析。【结果】PCR扩增结果表明:来自4个生理小种的8个菌株均可扩增得到568 bp的ITS单一片段,但这些生理小种间的片段没有明显的多态性;对这些生理小种ITS产物进行RFLP分析发现,不同生理小种之间的差异很小。【结论】PCR-RFLP技术不适用香蕉枯萎病菌生理小种的分析鉴定。

RFLP analysis of the ribosomal DNA ITS regions of four physiological races of Fusarium oxysporum f. sp. cubense

Objective] To clarify the phylogenetic relationship of four physiological races of Fusarium oxysporum f.sp.cubense (Foc), the causal agent of fusarial wilt of banana.Method] The ribosomal DNA internal transcribed spacer (ITS) regions of the four physiological races of Foc were first amplified using PCR technique, and then RFLP analysis of the ITS products of these races were performed using three restriction endonucleases including AIu I, Hpa II and Taq I.Result]A single 568 bp ITS fragment was amplified specifically from eight strains belonging to four races, respectively, but there was no obvious polymorphism among these races.RFLP analysis of the ITS products from these races showed that the differences among races were very small.Conclusion] PCR-RFLP technique was unsuitable to be used as the identification basis for the physiological races of Foc.