中文摘要：

为了明确棉花黄萎病菌大丽轮枝菌（Verticillium dahliae Kleb.）的VdSge1基因功能,本研究利用基因同源重组原理,通过构建敲除载体,对棉花黄萎病菌落叶型强致病力菌株V592的VdSge1基因进行了敲除,获得了4个目标基因敲除的突变体;以野生型菌株V592为对照,通过对敲除突变体生物学性状和致病性测定,结果表明,突变体的菌落生长速度、产孢量明显高于野生型,并且丧失对棉花的致病性。利用q RT-PCR对其他基因在突变体中的表达情况进行分析,结果表明,VdSge1基因敲除后,VMK1、VGB和VdGARP1的表达量随之下降,而VDH1和PevD1的表达却明显上升。由此说明,VdSge1基因与大丽轮枝菌的菌落生长速度、产孢量及致病性密切相关,并且可以影响其他一些基因的表达。

英文摘要：

Verticillium dahliae Kleb. is a phytopathogenic fungus and causative agent of cotton wilt disease. To characterize the V. dahliae Kleb. gene VdSge1, a targeted gene replacement strategy based on homologous recombination was adopted to generate VdSge1 deletion mutant strains from the virulent defoliating V. dahliae isolate V592 by Agrobacterium tumefaciens-mediated transformation. Four VdSge1 deletion mutants were selected for biological function and pathogenicity assays. All VdSge1 deletion mutants displayed greater radial growth and conidia production, as well as a loss in pathogenicity on cotton plants when compared to wild type V592. We also analyzed the expression of series of well-known functional genes in both V592 strain and VdSge1 deletion mutants by quantitative reverse-transcription polymerase chain reaction. The results showed that VdSge1 affects the transcription of five genes; in compared to V592 strain, VMK1, VGB and Vd GARP1 were significantly up-regulated in VdSge1 deletion mutants, whereas VDH1 and Pev D1 were strongly down-regulated in VdSge1 deletion mutants. In conclusion,our data suggest that V. dahliae VdSge1 plays a role in fungal development and pathogenicity, in addition to affecting the expression of other genes in this pathogenic fungus.