By infection with Fusarium oxysporum in greenhouse, bacterial physiological flora of cucumber rhizosphere was changed and enzymatic activities decreased. The population of nitrobacteria and nitrite bacteria decreased in the early and peak phases of infection, thereafter which enhanced growing of aerobic azotobacter and denitrifier. The population of ammonifying bacteria and cellulose-decomposition bacteria consistently decreased during infection period. The population of rhizosphere thiobacillus dropped dramatically concomitant of increase in anti-sulfuration bacteria. The impact of nitrobacteria in cucumbers was significantly different between susceptible and resistant varieties, which may play an important role in physiologic accommodations against of cucumber Fusarium wilt. After Fusarium oxysporum infection, the activities of rhizosphere enzymes were declined significantly in catelase, urease, cellulase and alkaline-phosphatase. In early infection, the decline of activities was observed for catelase and cellulase more remarkable in susceptible varieties than in resistant varieties. However, the extent of decline in late of infection was found for urease and phosphatase but more remarkable in resistant varieties than that in susceptible. The impact of catelase in resistance to the disease was different significantly between susceptible and resistant varieties, which can be used as reference in resistant breeding.%温室黄瓜感染枯萎病后,根际细菌生理菌群数量改变,酶活性下降.病害降低了染病初期和高峰期根际硝化细菌、亚硝酸细菌数量,促进了高峰期及后期的好气性自生固氮菌、反硝化细菌的生长;染病后,各个时期氨化细菌、纤维素分解菌均减少;患病根际硫化细菌数量大幅度下降,反硫化细菌的数量大幅度增多;硝化细菌在感抗品种中影响差异显著,可能对黄瓜枯萎病的发生起重要调节作用.感染枯萎病后,黄瓜根际过氧化氢酶活性、脲酶活性、纤维素酶活性、碱性磷酸酶活性减弱并达显著水平；前期感病品种比抗病品种过氧化氢酶、纤维素酶活性下降幅度大,后期则抗病品种比感病品种的脲酶、碱性磷酸酶活性下降幅度大；过氧化氢酶对感抗品种影响差异显著,可作为抗病育种参考.
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