| 摘要 | 第4-8页 |
| Abstract | 第8-12页 |
| 1 Introduction | 第15-27页 |
| 1.1 Background and Significance | 第15-16页 |
| 1.2 Research Status at Home and Abroad | 第16-26页 |
| 1.2.1 Production of ROS of plant under Cd stress | 第17-18页 |
| 1.2.2 Response of plant antioxidant system under Cd stress | 第18-22页 |
| 1.2.3 Nitric Oxide in Plant | 第22-26页 |
| 1.2.4 Alfalfa under heavy metals stress | 第26页 |
| 1.3 Purpose of the research | 第26-27页 |
| 2 Materials and methods | 第27-32页 |
| 2.1 Experiment materials | 第27-30页 |
| 2.1.1 Materials and Instruments | 第27页 |
| 2.1.2 Seeds treatment and Germination conditions | 第27-28页 |
| 2.1.3 The Measurement | 第28-30页 |
| 2.2 Assay Method | 第30-31页 |
| 2.2.1 Determination of NO content | 第30页 |
| 2.2.2 Germination parameters | 第30-31页 |
| 2.2.3 Seed storage substances | 第31页 |
| 2.2.4 Membrane lipid peroxidation | 第31页 |
| 2.2.5 System of antioxidant enzymes | 第31页 |
| 2.2.6 Accumulation of Cd | 第31页 |
| 2.3 Data analysis | 第31-32页 |
| 3 Results | 第32-54页 |
| 3.1 The production of NO in the alfalfa seeds under Cd stress | 第32-35页 |
| 3.1.1 The change in NOS activity | 第32-33页 |
| 3.1.2 The change in NR activity | 第33页 |
| 3.1.3 The change in Car content | 第33-34页 |
| 3.1.4 The change in NO_2~- content | 第34-35页 |
| 3.1.5 The change in NO content | 第35页 |
| 3.2 Effect of NO on germination and growth of alfalfa seeds under Cd stress | 第35-40页 |
| 3.2.1 Effect of exogenous NO | 第35-37页 |
| 3.2.2 Effect of endogenous NO | 第37-40页 |
| 3.3 Effect of NO on storage substance in alfalfa seeds under Cd stress | 第40-45页 |
| 3.3.1 Effect of exogenous NO | 第40-42页 |
| 3.3.2 Effect of endogenous NO | 第42-45页 |
| 3.4 Effect of NO on ROS metabolism in alfalfa seeds under Cd stress | 第45-52页 |
| 3.4.1 Effect of exogenous NO | 第45-49页 |
| 3.4.2 Effect of endogenous NO | 第49-52页 |
| 3.5 Effect of NO on Cd accumulation in alfalfa seeds under Cd stress | 第52-54页 |
| 4 Discussion | 第54-60页 |
| 4.1 The generation of NO in the alfalfa seeds germination under Cd stress | 第54-55页 |
| 4.2 Effect of NO on germination and growth of alfalfa during germination | 第55-56页 |
| 4.3 Effect of NO on storage material in alfalfa seeds during germination | 第56-57页 |
| 4.4 Effect of NO on ROS metabolism of alfalfa during germination | 第57-59页 |
| 4.5 Effect of NO on Cd accumulation in alfalfa during germination | 第59-60页 |
| Conclusion | 第60-62页 |
| Future Prospective | 第62-63页 |
| 致谢 | 第63-64页 |
| References | 第64-68页 |
| 攻读学位期间的研究成果 | 第68页 |
