高温胁迫下不同氮肥处理对高羊茅氮代谢的影响  

Effect of nitrogen fertilization on nitrogen metabolism of Festuca arundinacea under heat stress

作　　者：江宏娟[1] 李建龙[1] 李良霞[1] 王艳[1] 

机构地区：[1]南京大学生命科学院,江苏南京210093

出　　处：《草业科学》2009年第3期102-107,共6页Pratacultural Science

基　　金：国家高技术(863计划)专题项目(2007AA10Z231)

摘　　要：采用盆栽试验,研究了不同氮肥(NO3--N、NH4+-N、NH4NO3-N)处理对高羊茅品种凌志Festu-ca arundinaceacv.Barlexas在高温38/30℃(昼/夜)胁迫下叶片内硝态氮含量、铵态氮含量以及参与氮同化和代谢过程的主要酶活性的影响。结果表明:随着胁迫时间的延长,经过不同氮肥处理的植株中硝态氮含量先升后降,而铵态氮含量呈上升趋势,其中NH4NO3-N处理株的硝态氮含量最高,铵态氮含量最低,NH4+-N处理株的铵态氮含量最高;不同处理株中的硝酸还原酶(NR)活性呈下降趋势,而谷氨酰胺合成酶(GS)和谷氨酸合成酶(GOGAT)活性均呈先升后降的趋势,总体上,NH4NO3-N处理株的NR、GS和GOGAT活性最高;NH4NO3-N和NO3--N处理株的谷氨酸脱氢酶(GDH)活性均呈下降趋势,而NH4+-N处理株的GDH活性呈上升趋势。在试验条件下,经NH4NO3-N处理的高羊茅受氧化胁迫程度最小,耐热性最好,有利于高羊茅越夏和延长其绿期。The effects of different nitrogen treatments（NO3^-,NH4^＋ and NH4NO3） on the contents of nitrate and ammonium nitrogen,as well as the activity of main enzymes involving in the process of assimilation and metabolism in leaf of Festuca arundinacea under high temperature（38/30 ℃,day/night） were studied by plot experiment.The results indicated that the nitrate content increased at the beginning and then declined along with the stress treatment time,however,the ammonium nitrogen content showed an increasing trend.The nitrate content was the highest and the lowest was ammonium nitrogen content in the leaf treated by NH4NO3.The ammonium nitrogen content was the highest in the leaf treated by NH4^＋.The activity of nitrate reductase（NR） showed a decline trend under different treatments.The activity of glutamine synthetase（GS） and glutamate synthase（GOGAT） increased at the beginning and then decreased.In general,the activity of NR,GS and GOGAT in leaf treated by NH4NO3 was the highest.Activity of gl utamate dehydrogenase（GDH） in leaf treated by NH4NO3 and NO3^-showed a decline trend,and that of GDH treated by NH4^＋ showed an increasing trend.It could be concluded that the oxidative stress on F.arundinacea treated by NH4NO3 was the smallest and its heat tolerance was the best.

关 键 词：凌志高羊茅 氮含量 酶活性 高温胁迫 

分 类 号：S688.4[农业科学—观赏园艺]