关键词: 柑桔园土壤, 脲酶活性, 年周期变化, 抑制剂, 氢醌

Abstract: The preliminary results of our findings are summarized as follows:1. Annual variation of the urease activity of citrus orchard soil of red earth in southern subtrOpics. The urease activity was the lowest in winter, it rose quickly during spring and dropped gradually in summer and Autumn. 2. The hydroquinone was selected for laboratory test as urease inhibitor. The results showed that the hydroquinone exhibited significant inhibitive effect. The inhibitory rate increased as the increased concentration of hydroquinone while decreased with the increase of culture time. Duration of urea hydrolysis with the application of hydroquinone is once as long as that of the control.

Key words: Citrus orchard soil, Seasonal variation, Urease activity, Inhibitor, Hydroquinone