水稻白叶枯病菌(Xanthomonas oryzae pv.oryzae,Xoo)是一种重要的植物病原细菌,可以引起水稻白叶枯病,使水稻减产。本研究通过对Xoo K74 Tn5插入突变体库进行致病力检测、质粒拯救定位发现pxo_04104基因与Xoo致病相关,pxo_04104基因编码periplasmic beta-glucosidase(周质β-葡萄糖苷酶)。该基因的缺失突变体及其互补菌株生理生化表型检测显示缺失突变体致病力、抗渗透压能力显著下降,其互补菌株致病力可恢复到野生型水平的84.2%,抗渗透压能力也可恢复。本研究为深入研究pxo_04104基因致病分子机理提供了线索。 Xanthomonas oryzae pv. Oryzae (Xoo) is an important phytopathogenic bacterium that can cause rice bacterial leaf blight and reduce the yield of rice. In this study, pathogenicity of Xoo K74 Tn5 insertion mutant library was tested. Plasmid rescue localization indicated that pxo_04104 gene was associated with Xoo pathogenicity and pxo_04104 gene encoded periplasmic beta-glucosidase. Physiological and biochemical phenotypes of the deletion mutant and its complementary strains showed that the pathogenicity and anti-osmotic pressure of the mutant were significantly decreased, and the pathogenicity of the complementary strain recovered to 84.2% of the wild-type, and the anti-osmotic pressure Can be restored. This study provides a clues for further study of molecular pathogenesis of pxo_04104 gene.