Effects Of Nitrogen Nutrients On The Physiological Influences And Key Enzymes In Nitrogen Metabolism Of Different Genotypic Chinese Chive

Chinese chive was originally cultivated in China and had a long history of cultivation. Chinese chive has became one of the most important vegetables in north China because of great value of nutrition and medicine. Now the people had a lot of research on cultivation technique, the regularity of modality morphological development and physiological characteristics in Chinese chive. However, There is not the report about the effects of nitrogen(N) on yield, quality and key enzymes in nitrogen metabolism of Chinese chive in a hydroponics system. Chinese chive cultivar as experiment material ,the paper investigated that the effect of nitrogen on the physiological react and key enzymes in nitrogen metabolism which provided theoretical basis for Chinese chive cultivar breeding of low-nitrate accumulation and soiless culture.1. When the nitrogen concentration was in 8 mmol·L^-1, the yield, the content of Vc, soluble sugar and soluble protein were at higher level,but nitrate content was at low level. The content of nitrate was increased and NR activity decreased with the nitrogen concention incerased. Growth was depressing and yield ,quality were all decreased with high nitrogen and low oxgen concention streses in Chinese chive.2. NR was increased at high nitrogen (20 mmol-L"1) and reduced at low nitrogen (2 mmol-L"1);GS, GOT and GPT were increased then reduced with nitrogen increasing. NR, GPT of ZGJC Chinese chive had no significant difference with control at low nitrogen, and the same as GOT of ZGJC at high nitrogen.3 With nitrogen increasing, nitrate content was increased in six Chinese chives, and there was significant difference among these varieties. Under high nitrogen (20 mmol-L"1) and control (8 mmol-L"1), nitrate content of PJ4 was 1.79 and 1.20 times as low nitrogen (2 mmol-L"1) respectively, and that of ZGJC was 1.83 and 1.58 times. Key enzymes except GS in nitrogen metabolism had significant difference with its nitrate content. The results indicated that genotypic difference had an effect on the response of key enzymes in nitrogen metabolism to nitrogen stress, and nitrate content significantly correlated with nitrogen assimilation.4. Six different genotypic Chinese chive were conduct to look at the effect of different genotypics root morphological characteristic on different nitrogen form and conbine.The results showed that nitrate induced the root growth of Chinese chive, root length root number and root volum were all increased as nitrate content accumution increasing.Under NO₃^-—N treatment and nitrogen combine ,root length of QYJC, PJ2, HZDJ, ZGJC were 1.19,1.13,1.20,1.06,1.19,1.11,1.11,1.05 times as NH₄⁺-N treatment ,respectively.Root number of QYJC, PJ2, ZGJC were 1.18, 1.14, 1.12, 1.07, 1.11, 1.08times。 Root voolum of QYJC, PJ2, 791, ZGJC were 1.21, 1.09, 1.15, 1.09, 1.15, 1.10, 1.17, 1.07 times, respectively.Living area, total area, total area volum, R/S of different genotypic was increasing with nitrate increasing.5 This result of experiment showed that yield and nutriention of different Chinese chive variety have different responses to nitrate , and which key enzymes in nitrogen metabolism significantly correlated with nitrate content , providing theoretical basis for low nitrate accumulation Chinese chive cultivar selection.The experiment determined the root morphological of six different Chinese chive under different nitrate treatment ,which first demonstrated that nitrate indicated root growth and development .The paper impoved the theory of nitrogen resistance of Chinese chive.