有机肥施用水平对紫花苜蓿粗蛋白含量及氮代谢关键酶活性的影响

Effects of organic fertilizer level on the content of crude protein and activities of key enzymes in nitrogen metabolism of alfalfa

试验以铁尾矿砂为基质,采用室外盆栽的方式,研究了有机肥施用水平对紫花苜蓿不同发育期各器官中粗蛋白含量和氮代谢关键酶活性的影响。结果表明:随着有机肥施用量的增加紫花苜蓿各器官中的粗蛋白含量和硝酸还原酶活性逐渐提高,并且在初花期达到峰值,之后逐渐下降;有机肥施用水平与粗蛋白含量间存在明显的正相关关系。茎和根中的粗蛋白含量与硝酸还原酶(NR)活性显著正相关。适当增加施肥量(1%,2.5%)可提高各器官中谷氨酰胺合成酶(GS)和谷氨酸脱氢酶(GDH)活性,有机肥施用量过高(5%)其活性反而下降。有机肥施用量没有改变各器官中氮代谢酶活性的变化趋势。

It was investigated that the effects of organic fertilizer level on the content of crude protein and activities of key enzymes in nitrogen metabolism of alfalfa ,planted in iron tail‐ings ,at different growth stages by pot experiment in this paper .The results showed that the content of crude protein and the activities of nitrate reductase （NR） increased gradually with the fertilization level increasing ,and reached maximum at initial bloom stage and decreased af‐terwards .There was significantly positive correlation between the fertilization level and con‐tent of crude protein .The significantly positive correlation was also found between the con‐tent of crude protein and activities of NR in stalk and root of alfalfa .The activities of both GS and GDH were improved by organic fertilizer application at suitable level （1% ,2 .5% ） ,but decreased when excessive organic fertilizer （5% ） was used .Fertilization level did not affect the changing tendency of the activities of key enzymes in nitrogen metabolism in organs of al‐falfa at different grow th stages .