氮素营养对水稻生育后期叶片衰老过程活性氧积累与茎鞘同化物转运影响的生理特征
发布时间：2024-01-15 20:21
水稻抽穗灌浆期是水稻产量形成的关键时期,若叶片提早衰老,会引起碳水化合物供应短缺,籽粒灌浆不足,最终影响水稻的产量和品质。目前生产上种植的水稻类型主要是稻穗大而饱满高产、超高产杂交稻,因而,籽粒灌浆过程中碳水化合物供求与旗叶早衰之间的矛盾也愈发突出。施用氮肥可延缓叶片衰老,提高粮食产量,但施氮过多会造成环境污染、氮肥利用率低、稻米品质劣化、病虫害以及减产等不利后果。因此,研究水稻籽粒灌浆期叶片早衰发生机理、探索氮素抑制和延缓叶片衰老的调控机理,对水稻生产具有重要意义。因此,本研究以叶片早衰突变体水稻(psf)及其野生型对照7954(WT)为材料,通过进行不同氮水平处理,探析氮素营养对水稻生育后期叶片衰老过程活性氧积累与茎鞘同化物转运影响的生理特征。主要研究结果如下:1.缺氮会导致叶片衰老提前发生,同时加速叶片衰老的进程。低氮(LN)处理可增强OsNCEDs的表达,抑制Osaba8ox2和Osaba8ox3的表达。高氮(HN)处理条件下,叶片ABA含量降低,推迟了叶片衰老的产生和发展。对水稻叶片进行外源ABA处理,结果显示,ABA以剂量依赖的方式促进了H2O
【文章页数】：141 页
【学位级别】：博士
【文章目录】：
Acknowledgement
Abstract
摘要
Introduction
Background information for the experimental materials
Objectives of the study
Chapter1 Review of literature
1.1 Regulations of leaf senescence
1.1.1 Senescence process
1.1.2 Structural and biochemical changes in leaf during senescence
1.1.3 Involvement of phytohormone in the regulation of leaf senescence
1.2 Effect of Nitrogen supply on leaf senescence
1.2.1 Photosynthetic N metabolism and assimilation
1.2.2 Photosynthetic carbon(C)metabolism during senescence
1.2.3 Regulation of C and N metabolism in response to nitrogen availability
1.3 Effect of N on nonstructural carbohydrate(NSC)reserve and remobilization
1.4 Molecular approaches to understanding leaf senescence
Chapter2 Relationship of Nitrogen Deficiency-Induced Leaf Senescence with ROS Generation and ABA Concentration in Rice Flag Leaves
2.1 Introduction
2.2 Materials and Methods
2.2.1 Plant materials and nitrogen treatment
2.2.2 Exogenous ABA incubation experiment in detached leaves
2.2.3 Measurement of net photosynthetic rate(Pn),chlorophyll content,hydrogen peroxide(H2O2)concentration,malondialdehyde(MDA)level,soluble protein content,and ABA concentration in rice leaves
2.2.4 Enzymatic assay of glutamine synthetase(GS)and glutamate dehydrogenase(GDH)in rice leaves
2.2.5 RNA extraction,cDNA preparation,and Quantitative real-time PCR
2.2.6 Statistical analysis
2.2.7 Design of key enzyme primers for regulating ABA synthesis and catabolism
2.3 Results
2.3.1 Senescence-associated changes in endogenous ABA accumulation,H2O2 production,and activity of key enzymes involving in nitrogen metabolism under different N supply levels
2.3.2 Transcriptional expression of some key genes involving in ABA biosynthesis and its catabolism for two rice genotypes imposed to different N levels
2.3.3 Linking the exogenous ABA-regulated leaf senescence with H2O2 generation and N metabolism in rice leaves
2.4 Discussion
Conclusion
Chapter3 Senescence-Related Translocation of Nonstructural Carbohydrate(NSC)in Rice Leaf Sheathes Under Different Nitrogen Supply
3.1 Introduction
3.2 Materials and Methods
3.2.1 Plant materials and nitrogen treatment
3.2.2 Measurement of net photosynthetic rate(Pn)and chlorophyll content in rice leaves
3.2.3 Determination of soluble sugar content, starch content, and NSC amount in leaf sheaths
3.2.4 Enzymatic extraction and assays of SPS,FBPase,Susy,GS,GOT,and GPT in leaf sheaths
3.2.5 Statistical analysis
3.3 Result
3.3.1 Effect of N supply levels on leaf senescence and grain yield and also its relation to the NSC translocation and starch accumulation in leaf sheaths
3.3.2 Positional variations in the NSC amount,total soluble sugar content,and starch accumulation in leaf sheathes under different N supply levels
3.3.3 Effect of N supply levels on the activities of several key enzymes involving in NSC metabolism in the leaf sheath and its positional variation among three leaf sheaths
3.4 Discussion
Conclusion
Chapter4 Senescence-Related Changes in Nitrogen Metabolism and Carbohydrate translocation in Rice Leaves under Different Nitrogen Supply
4.1 Introduction
4.2 Materials and Methods
4.2.1 Plant Materials and Nitrogen Treatment
4.2.2 Determination of net photosynthetic rate(Pn),chlorophyll content,and Relative conductivity
4.2.4 Determination Carbon and Nitrogen metabolism-related indicators
4.2.5 Carbon and Nitrogen Metabolism-related Enzyme Assay
4.2.6 RNA isolation,cDNA preparation,and Quantitative real-time PCR
4.2.7 Statistical analysis
4.3 Results
4.3.1 Senescence-associated changes in leaf Chla/Chlb,total soluble sugar,sucrose,starch,soluble protein,and total N contents under different nitrogen supply
4.3.2 N deficiency induced C/N imbalance in the flag leaves during grain filling
4.3.3 Transcriptional profile of key genes involving in carbon and nitrogen metabolism for two rice genotypes imposed to N deficiency/overfeeding
4.4 Discussion
Chapter5
5.1 Major findings
5.2 Future perspectives
References
List of Publications
本文编号：3878788
【文章页数】：141 页
【学位级别】：博士
【文章目录】：
Acknowledgement
Abstract
摘要
Introduction
Background information for the experimental materials
Objectives of the study
Chapter1 Review of literature
1.1 Regulations of leaf senescence
1.1.1 Senescence process
1.1.2 Structural and biochemical changes in leaf during senescence
1.1.3 Involvement of phytohormone in the regulation of leaf senescence
1.2 Effect of Nitrogen supply on leaf senescence
1.2.1 Photosynthetic N metabolism and assimilation
1.2.2 Photosynthetic carbon(C)metabolism during senescence
1.2.3 Regulation of C and N metabolism in response to nitrogen availability
1.3 Effect of N on nonstructural carbohydrate(NSC)reserve and remobilization
1.4 Molecular approaches to understanding leaf senescence
Chapter2 Relationship of Nitrogen Deficiency-Induced Leaf Senescence with ROS Generation and ABA Concentration in Rice Flag Leaves
2.1 Introduction
2.2 Materials and Methods
2.2.1 Plant materials and nitrogen treatment
2.2.2 Exogenous ABA incubation experiment in detached leaves
2.2.3 Measurement of net photosynthetic rate(Pn),chlorophyll content,hydrogen peroxide(H2O2)concentration,malondialdehyde(MDA)level,soluble protein content,and ABA concentration in rice leaves
2.2.4 Enzymatic assay of glutamine synthetase(GS)and glutamate dehydrogenase(GDH)in rice leaves
2.2.5 RNA extraction,cDNA preparation,and Quantitative real-time PCR
2.2.6 Statistical analysis
2.2.7 Design of key enzyme primers for regulating ABA synthesis and catabolism
2.3 Results
2.3.1 Senescence-associated changes in endogenous ABA accumulation,H2O2 production,and activity of key enzymes involving in nitrogen metabolism under different N supply levels
2.3.2 Transcriptional expression of some key genes involving in ABA biosynthesis and its catabolism for two rice genotypes imposed to different N levels
2.3.3 Linking the exogenous ABA-regulated leaf senescence with H2O2 generation and N metabolism in rice leaves
2.4 Discussion
Conclusion
Chapter3 Senescence-Related Translocation of Nonstructural Carbohydrate(NSC)in Rice Leaf Sheathes Under Different Nitrogen Supply
3.1 Introduction
3.2 Materials and Methods
3.2.1 Plant materials and nitrogen treatment
3.2.2 Measurement of net photosynthetic rate(Pn)and chlorophyll content in rice leaves
3.2.3 Determination of soluble sugar content, starch content, and NSC amount in leaf sheaths
3.2.4 Enzymatic extraction and assays of SPS,FBPase,Susy,GS,GOT,and GPT in leaf sheaths
3.2.5 Statistical analysis
3.3 Result
3.3.1 Effect of N supply levels on leaf senescence and grain yield and also its relation to the NSC translocation and starch accumulation in leaf sheaths
3.3.2 Positional variations in the NSC amount,total soluble sugar content,and starch accumulation in leaf sheathes under different N supply levels
3.3.3 Effect of N supply levels on the activities of several key enzymes involving in NSC metabolism in the leaf sheath and its positional variation among three leaf sheaths
3.4 Discussion
Conclusion
Chapter4 Senescence-Related Changes in Nitrogen Metabolism and Carbohydrate translocation in Rice Leaves under Different Nitrogen Supply
4.1 Introduction
4.2 Materials and Methods
4.2.1 Plant Materials and Nitrogen Treatment
4.2.2 Determination of net photosynthetic rate(Pn),chlorophyll content,and Relative conductivity
4.2.4 Determination Carbon and Nitrogen metabolism-related indicators
4.2.5 Carbon and Nitrogen Metabolism-related Enzyme Assay
4.2.6 RNA isolation,cDNA preparation,and Quantitative real-time PCR
4.2.7 Statistical analysis
4.3 Results
4.3.1 Senescence-associated changes in leaf Chla/Chlb,total soluble sugar,sucrose,starch,soluble protein,and total N contents under different nitrogen supply
4.3.2 N deficiency induced C/N imbalance in the flag leaves during grain filling
4.3.3 Transcriptional profile of key genes involving in carbon and nitrogen metabolism for two rice genotypes imposed to N deficiency/overfeeding
4.4 Discussion
Chapter5
5.1 Major findings
5.2 Future perspectives
References
List of Publications
本文编号：3878788
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