干旱地区农业研究2017，Vol.35Issue(3)：151-158,8.DOI:10.7606/j.issn.1000-7601.2017.03.24
外源一氧化氮对Na2CO3胁迫下南瓜幼苗碳氮代谢的影响
Effects of exogenous nitric oxide on the growth and carbon and nitrogen metabolism of pumpkin seedlings under Na2CO3 stress
摘要
Abstract
Iu order to explore the effects of exogenous nitric oxide on metabolism process of carbon and nitrogen of pumpkin seedlings,a pot experiment was conducted to study the effects of 80 μnol · L-1 SNP on the growth of seedlings,the contents of chloroplast pigments,the activities of carbon and nitrogen metabolism related enzymes and the amount of metabolites of pumpkin (cv.Yinhui No.2) seedlings under the stress of 60 mmol· L-1 Na2CO3.The results showed that aboveground and underground dry weight,relative growth rate,root shoot ratio,Rubisco carboxylase activity,light enzyme activity of photosynthetic pigment contents and nitrogen metabolism were decreased in different degrees,while Rubisco oxidation activity,total free amino acids and proteolytic enzyme activity were significantly increased when the seedlings exposed to 60 rmmol· L-1 Na2CO3 for 12 d.Application of 80 μmol· L-1 SNP obviously alleviated the inhibition effects of Na2CO3 stress on the seedling growth and photosynthesis,as it increased the plant dry matter and leaf chlorophyll content.Compared with Na2CO3 stress treatment,80 μmol· L-1 SNP considerably increased dry matter accumulation,relative dry weight,chlorophyll content,carotenoid content,nitrate reductase,glutamine synthetase,carboxylase,amylase activity and soluble protein accumulation by 26.72％,30.45％,17.69％,46.15％,46.43％,30.70％,38.75％,70.0％,65.37％,respectively,while decreased protease,oxygenase activity,free amino acid content by 18.29％,31.76％,28.57％.Meanwhile,exogenous NO maintained the stability of total soluble sugar content by in creasing the activity of amylase and Rubisco carboxylation and decreasing the oxidative activity.Exogenous NO also inhibited the activity of proteolytic enzymes and glutamate dehydrogenase (GDH),decreased the content of free amino acids in leaves,and increased the accumulation of protein by increasing the activity of NR,GS and glutamate synthase (GOGAT).Under alkaline salt stress,80 μrnol· L-1 SNP promoted the keto acid translating into amino acids through the enhancement of pumpkin seedlings photosynthetic carbon metabolism.Meanwhile,by improving the activity of related enzymes NR,GS,GOGAT,80 μmol· L-1 SNP caused the switch of carbon to nitrogen,maintaining the balance between them under salt stress of Na2CO3.关键词
一氧化氮/Na2CO3胁迫/碳氮代谢/南瓜/代谢产物Key words
nitric oxide/Na2CO3 stress/carbon and nitrogen metabolism/pumpkin/metabolic substances分类
农业科技引用本文复制引用
吴旭红,罗贵强,冯晶旻..外源一氧化氮对Na2CO3胁迫下南瓜幼苗碳氮代谢的影响[J].干旱地区农业研究,2017,35(3):151-158,8.基金项目
黑龙江省教育厅科学技术研究项目(10551332) （10551332）
