硝酸盐对大豆共生固氮的影响

EFFECT OF NITRATE ON SYMBIOTIC NITROGEN FIXATION OF SOYBEAN

大豆施用硝酸盐的试验结果表明,高浓度硝酸盐对吉林20号和长农4号的共生固氮有明显的抑制作用。低浓度硝酸盐在生育前期对吉林20号根瘤固氮酶活性有促进作用,酰脲含量增加,在生育后期有抑制作用。但生育前期低浓度硝酸盐对长农4号根瘤固氮酶活性有明显的抑制作用,酚脲含量减少。施用硝酸盐对大豆根瘤尿囊素酶活性都有抑制作用,生育前期比后期明显,高浓度比低浓度明显。

In this experiment the nitrate was applied to the soybean 'Jilin 20' and 'Changnong 4'.The results showed that the symbiotic nitrogen fixation of Jilin 20 and Changnong 4 wes inhibited by high nitrate concentration.If low nitrate concentration was applied to Jilin 20,its nodule nitrogenase activity and ureide content were increased in early growth period,but were inhibited in later growth period.On the contrary,when low nitrate concentration was applied to Changnong 4,its nodule nitrogenase activity was inhibited and ureide content decreased in early growth period.The allantoinase activity of soybean nodule was inhibited by Application of nitrate.The inhibition was more obvious in early growth stages than in later growth stages.