缺氮复氮处理对玉米根系生长、根系活力、硝态氮及氨基酸含量的影响

为明确缺氮复氮处理对根系生长、根系活力、硝态氮含量及氨基酸含量的影响，对水培玉米幼苗进行研究。结果表明，缺氮处理的根系总长、根表面积、分根数比正常处理的较大，复氮处理后各测定指标均有一定恢复；缺氮处理根系活力显著下降，降幅达50.91%，复氮处理后根系活力有所恢复，但仍然降低42.15%；缺氮根系的NO₃^- N含量比正常处理降低76.21%，复氮处理后NO₃^- N含量仍然降低40.97%；缺氮根系的天冬氨酸、苏氨酸、丝氨酸、谷氨酸、脯氨酸、甘氨酸和丙氨酸的含量明显下降，复氮处理后这些氨基酸含量仍然低于正常处理。

Effect of N Deficiency and N Recovery Treatment on Root Growth, Root Activity, Content of NO3- N and Amino Acids

To understand the influence of N deficiency and N recovery treatment on root growth, root activity, content of NO₃^- N and amino acids, the research was performed using solution culture maize seedlings. The roots showed that total root length, root surface area, split root number, the lateral root were larger under nitrogen deficiency than the normal treatment. And these items recovered in some extent under N recovery treatment. Root activity declined greatly under N deficiency treatment, the decline was 50.91%; when recovering N, root activity could be recovered, but the activity still declined 42.15%. Root NO₃^- N content decreased significantly, the decline was 76.21% under N deficiency; the content recovered to some extent when recovering N, but still lower 40.97% than the normal treatment. Content of Asp, Thr, Ser, Glu, Pro, Gly and Ala in root decreased under N deficiency treatment; when recovering N, these seven amino acids content were still lower than normal treatment.