外源亚精胺对高温胁迫下番茄幼苗抗氧化系统的影响
时间:2018-08-26 21:09 来源:毕业论文 作者:毕业论文 点击:次
| 摘要：以“浦红968”番茄品种为实验材料，采用基质栽培，研讨了叶片喷施亚精胺对高温胁迫下番茄幼苗叶片氧化损伤程度和抗氧化保护系统的影响。结果表明：高温胁迫下，番茄幼苗叶片活性氧（ROS）显著升高，膜质过氧化损伤加重。外源亚精胺（Spd）处理显著提高了高温胁迫下番茄幼苗叶片中超氧化物歧化酶（SOD）、过氧化物酶（POD）、过氧化氢酶（CAT）、抗坏血酸过氧化物酶（APX）、脱氢抗坏血酸还原酶（DHAR）这些抗氧化酶的活性；同时，外源Spd处理显著增加了幼苗叶片中抗坏血酸（AsA）和还原型谷胱甘肽（GSH）含量，提高了AsA和GSH所占的比例，文持了胞内氧化还原平衡。综上结果得出，外源Spd可以通过激活抗氧化酶和非酶抗氧化剂这两大抗氧化系统，显著降低超氧阴离子（O2.–）产生速率和过氧化氢（H2O2）、丙二醛（MDA）含量，缓解高温胁迫对番茄幼苗造成的氧化胁迫，降低膜脂过氧化程度。27454 毕业论文关键词：番茄；Spd；高温胁迫；抗氧化系统 Effects of exogenous spermidine on antioxidant system of tomato seedlings exposed to high temperature stress Abstract：This experiment which discussed the effects of foliar spraying spermidine on oxidative stress and antioxidant protective system of Tomato Seedlings under high temperature stress was carried out with "Pu Hong 968" tomato varieties in substrate culture.The results show that under high temperature stress, the ROS (O2.– production rate and H2O2 content) of tomato seedlings increased significantly, and the damage of membrane peroxidation was aggravated.Exogenous Spd treatment increased the activity of SOD, POD, CAT, APX, DHAR under high temperature significantly.Meanwhile, exogenous Spd significantly increased the content of antioxidants (AsA and GSH) in the leaves of seedlings,the proportion of AsA and GSH was also increased,so the intracellular redox balance was maintained.Results show that the exogenous Spd can activate antioxidant enzymes and non enzymatic antioxidant so that O2.– production rate,H2O2 content and MDA content will be decreased significantly.Oxidative stress induced by high temperature stress on Tomato Seedlings and lipid peroxidation will be reduced. Key words: tomato; spermidine; high temperature stress; antioxidant system 目 录 摘要 1 关键词 1 Abstract 1 Key words 1 引言 1 1 材料与方法 2 1．1 材料与设计 2 1．2 测定及分析方法 3 1．2．1 活性氧产生 3 1．2．2 丙二醛含量和电解质渗透率 3 1．2．3 抗氧化酶活性 3 1．2．4 非酶抗氧化剂 3 2 结果与分析 3 2．1 外源亚精胺对高温胁迫下番茄幼苗活性氧产生的影响 3 2．2 外源亚精胺对高温胁迫下番茄幼苗膜脂伤害的影响 4 2．3 外源亚精胺对高温胁迫下番茄幼苗抗氧化酶活性的影响 4 2．4 外源亚精胺对高温胁迫下番茄幼苗非酶抗氧化剂含量的影响 5 3 讨论 7 致谢 8 参考文献 8 图1 外源Spd对高温胁迫下番茄幼苗叶片H2O2含量和O2.–产生速率的影响 3 图2 外源Spd对高温胁迫下番茄幼苗叶片MDA含量和电解质渗透率的影响 4 图3 外源Spd对高温胁迫下番茄幼苗叶片SOD、CAT和POD活性的影响 4 图4 外源Spd对高温胁迫下番茄幼苗叶片APX、GR、MDHAR和DHAR活性的影响 5 (责任编辑：qin) |