Abstract: In this article,flue-cured tobacco(Nicotiana tobacum K326)was selected to study effects of water and nitrogen coupling on dynamic changes of soil enzymatic activities of catalase,sucrase,urease and acid phosphatase during the growth stage of flue-cured tobacco by net house cultivation with conditions of 3 levels of water irrigation(40,60 and 80 L/plant)and 4 levels of nitrogen application(0,3,7 and 12 g/plant).The results showed,the soil enzymatic activities of catalase,sucrase,urease and acid phosphatase increased first and then decreased with the advance of growth stage in flue-cured tobacco,and maximized at vigorous growing stage or budding stage.With the same growth period and the same water irrigation,the soil enzyme activities of catalase,sucrase and acid phosphatase increased first and then decreased with the advance of growth stage in flue-cured tobacco,while the urease activity of soil increased continuously with the advance of growth stage.Activities of the catalase and sucrase peaked at 3 g/plant,and acid phosphatase activity peaked at 7 g/plant and the urease activity peaked at 12 g/plant.With the same growth period and the same nitrogen application,above four soil enzyme activities were all higher with the range of 60-80 L/plant of water irrigation,while they were lowest with the level of 40 L/plant of water irrigation.In a word,the four of soil enzymatic activities were higher with the range of 60-80 L/plant and nitrogen 3-7 g/plant.

Key words: Water and nitrogen coupling, Flue-cured tobacco, Soil enzymatic activities

CLC Number: 

• S572