中文摘要：

采用砂培试验方法，系统研究了不同水平氮锌配施对白三叶生长和生理生化特性的影响。结果表明，在缺锌条件下，随施氮水平增加，白三叶氮代谢和清除活性氧的能力、IAA、GAs含量下降，ABA、MDA含量增加，氮锌配施对生长和元素吸收表现为拮抗效应；在足量供锌条件下，与低量供氮相比，中量供氮时，白三叶氮代谢和清除活性氧的能力、IAA、GAs含量增加，ABA、MDA含量下降，氮锌配施对生长和元素吸收表现为协同效应。当高量氮时，氮锌配施则表现为拮抗效应。在判断氮锌复合作用类型时，应区分生长量变化引起的“浓缩效应”和“稀释效应”，应以生长量和吸收量变化来确定氮锌复合作用的类型。

英文摘要：

Sand culture experiment, biochemical determination and plant analysis were used to investigate the effects of N and Zn combined application on growth of white clover, concentration of N and Zn in plant, as well as related mechanisms. The main findings showed that the effects of combined N and Zn application on growth, absorption and concentration of N and Zn of white clover as well as their physiological - biochemical characteristics were different at various levels of N and Zn. Under the condition of Zn deficiency, the content of IAA, GAs and SOD decreased and the content of ABA and MDA increased. Therefore, the growth and N and Zn absorption of white clover showed antagonism effect with the increasing rate of N supply. However,under the condition of Zn sufficiency, the content of IAA, GAs and SOD increased and the content of ABA and MDA decreased by suitable amount of N supply. Consequently, the growth and N and Zn absorption of white clover displayed synergism effect. Nevertheless, with high amount of N supply, the growth and N and Zn absorption of white clover displayed antagonism effect. The condensation effect and dilution effect should be considered when determining the types of N and Zn compound effect. The changes of growth rate and absorption rate of N and Zn should be used to determine the types of N and Zn compound effect.