摘  要：本实验通过水培法培养大麦，以大麦幼苗为材料，研究外施不同浓度（0、2、2.5、3、3.5、4g•L-1）的ASA对盐胁迫下大麦幼苗的生长及生理指标的影响，以期揭示ASA增强大麦耐盐性的生理机制，为开展大麦种质资源研究和确立大麦盐渍地优质高产稳产提供理论依据。结果显示，在盐胁迫下，大麦幼苗株高、根长、鲜重、叶绿素含量、根系活力显著降低，超氧阴离子产生速率、POD活性、MDA含量显著增加；外施ASA提高了盐胁迫下幼苗叶片的叶绿素含量、POD活性和根系活力，使MDA含量和超氧阴离子产生速率降低。由此可见，喷施ASA可以降低膜脂过氧化伤害程度，文持细胞膜的稳定性，从而缓解了盐胁迫对幼苗的伤害，并且外源ASA浓度在3g•L-1时达到最好的缓解效果。33763
毕业论文关键字：抗坏血酸；盐胁迫；大麦幼苗；缓解效应
  Effects of exogenous ascorbic acid on the growth and physiological indexes of barley seedlings
Abstract: Through the experiments of hydroponics culture of barley and using barley seedlings as materials, effects of the different concentration ascorbic acid (0、 2、 2.5、 3、 3.5、 4 g•L-1 ) on the growth and physiological indicators of barley seedling under salt stress. In order to reveal the physiological mechanism of ASA enhanced the salt tolerance of barley, and to provide a theoretical basis for the research of barley germplasm resources and the establishment of high yield and high quality of barley in saline soil.The results showed that under salt stress, the contents of barley seedling height, root length, fresh weight, chlorophyll content and root activity decreased significantly.The superoxide anion production rate, POD activity, MDA content were significantly increased .Exogenous ASA application on the leaves increased the chlorophyll content, POD activity and root activity.The content of MDA and superoxide anion production rate were decreased.The results showed that exogenous ASA could effectively keep cytomembrane stabilization and reduce the damage from membrane lipid peroxidation,by which could mitigate the harmful effects from salt stress on plants,and the effect of 3g•L-1 ASA was optimal.
Key Word:Ascorbic acid;Salt Stress; Rape Seedling; Mitigative effect
目    录
摘  要    1
Abstract    1
引 言    2
1. 材料与方法    3
1.1 实验材料    3
1.2 处理方法    3
1.3测定项目与方法    3
1.4 数据分析    3
2. 结果与分析    3
2.1 ASA喷施对盐胁迫下大麦幼苗部分生长指标的影响     4
2.2 ASA喷施对盐胁迫下大麦幼苗光合色素影响    4
2.3 ASA喷施对盐胁迫下大麦幼苗根系活力的影响    5
2.4 ASA喷施对盐胁迫下大麦幼苗POD活性的影响    5
2.5 ASA喷施对盐胁迫下大麦幼苗MDA含量的影响    6
2.6 ASA喷施对盐胁迫下大麦幼苗超氧阴离子产生速率的影响    6
3. 讨论    7
4. 结论    8
参考文献    9
致谢    12
外源抗坏血酸对盐胁迫下大麦幼苗生长及生理指标的影响
引言
大麦属于禾本科的植物，主要用作粮食、饲料、啤酒、工业原料以及医药工业原料和保健食品，是世界上栽培历史最悠久的作物之一，已经有几千年的种植历史[1]。世界谷类作物中，大麦种植总面积和总产量仅次于小麦、水稻、玉米、而居第四位[2]。中国的大麦现多产于淮河流域等以北地区，具有生理周期短，早熟、高产、适应能力强等特点，是禾本科中比较耐盐的作物[3]。 外源抗坏血酸对盐胁迫下大麦幼苗生长及生理指标的影响:http://www.751com.cn/shengwu/lunwen_31066.html