Abstract: In order to understand the effect of nitrate stress on nirtogen assimilation related enzyme activity of maize,on the basis of previous research,Zheng 58,Zhengdan 958 and Chang 7-2 as study materials,under the nitrate stress of different concentrations,nitrate reductase,glutamine synthetase,measuring superoxides dismutase activity were analyzed using solution culture method.It was revealed that changes of three enzymes activity of maize seedlings at suitable,high,low concentrations of nitrate supply conditions.The results showed that SOD activity of roots and leaves were low when nitrate concentration was 2.00 mmol/L,indicating that the concentration range was suitable for maize seedlings.Low (0.02,0.20 mmol/L),high (10.00,20.00 mmol/L) at a concentration of nitrate conditions,SOD activity was significantly increased in vivo hybrids Zhengdan 958,which was significantly higher than SOD activity of the parental species Zheng 58 and Chang 7-2 (P <0.05).It showed that Zhengdan 958 varieties had a higher self-protection role under stress conditions.With the increasing concentration of nitrate supply NR and GS activity were increased at low concentration of nitric acid (0.02,0.20 mmol/L),At high nitrate concentrations (10.00,20.00 mmol/L),NR and GS activity were decreased.NR activity of leaves decreased less than the root,indicating greater nitrate supply changed in the root.The reduction of nitrate of paternal Chang 7-2 was significantly weaker than the female offspring Zheng 58 and Zhengdan 958 and in particular it was significant differences (P <0.05) under stress conditions.GS trends and NR enzyme activity were similar.

Key words: Zea mays L., Nitrate stress, Nitrate reductase, Glutamine synthetase, Superoxide dismutase (SOD)

CLC Number: 

• S513