施氮量对冬小麦根际土壤酶活性的影响

Effects of nitrogen application rate on soil enzyme activities in wheat rhizosphere

在大田高产条件下,研究了不同施氮水平对大穗型小麦品种兰考矮早八和多穗型小麦品种豫麦49-198根际土壤酶活性的影响.结果表明:两种穗型冬小麦品种根际土壤酶活性随生育进程的变化趋势一致,即蛋白酶、脲酶及脱氢酶活性均呈先升后降的变化趋势;过氧化氢酶活性随生育进程的推进逐渐增加,在成熟期达到最大值.在同生育时期内,随着施氮水平的提高,土壤蛋白酶、过氧化氢酶及脱氢酶活性均呈先增后降的变化趋势,以180kgN.hm-2施氮水平的活性最高;脲酶活性则随施氮水平的提高而上升,在360kgN.hm-2施氮水平下达到最高.

This paper studied the effects of nitrogen application rate on the soil enzyme activities in the rhizosphere of wheat cuhivars Lankaoaizao 8, a large spike genotype, and Yumai 49-198, a small spike genotype, under high yield condition. The results showed that the enzyme activities in rhizosphere soil had similar changing trends with wheat growth. The protease, urease and dehydrogenase activities in rhizosphere soil increased with wheat growth, maximized at heading stage, jointing stage, and heading stage, respectively, and decreased thereafter. Catalase activity increased with wheat growth, and peaked at maturing stage. At the same growth stage, the protease, catalase and dehydrogenase activities in rhizosphere soil of the two cultivars increased with increasing nitrogen application rate and peaked at 180 kg N·hm^-2. Urease activity also increased with increasing nitrogen application rate, and the maximum activity was observed at 360 kg N·hm^-2.