外源葡萄糖对盐胁迫下黄瓜幼苗生长和抗氧化代谢的影响
时间:2018-07-12 10:30 来源:毕业论文 作者:毕业论文 点击:次
| 摘要：以黄瓜‘津优四号’品种为试验材料，采用营养液栽培，研究叶面喷施外源葡萄糖（100mM）对盐胁迫下（75mM NaCl）黄瓜幼苗生长和抗氧化代谢的影响。结果表明，盐胁迫下黄瓜幼苗正常生长受到抑制，而叶面喷施外源葡萄糖可以缓解盐胁迫诱导的生长抑制。盐胁迫显著增加黄瓜叶片丙二醛（MDA）含量和超氧阴离子（O2∙-）产生速率，降低超氧化物歧化酶（SOD）、过氧化物酶（POD）和抗坏血酸过氧化物酶（APX）活性。盐胁迫下，施用葡萄糖显著提高黄瓜叶片SOD、POD和APX活性及其基因表达，降低O2∙- 产生速率和MDA含量。说明外源葡萄糖可通过调节盐胁迫下黄瓜幼苗抗氧化酶编码基因的表达，提高抗氧化酶的活性，降低氧化伤害，促进幼苗生长，从而提高黄瓜幼苗植株的耐盐性。25676 毕业论文关键词：盐胁迫；黄瓜；葡萄糖；抗氧化代谢；基因表达 Effects of exogenous glucose on growth and antioxidant metabolism of cucumber seedlings under salt stress Abstract：Effects of exogenous glucose (100mM) on the growth and antioxidant metabolism of cucumber seedlings under salt stress (75mM) were studied using cucumber cultivar ‘Jinyou No4’ as experimental material and nutrient solution cultivation. The results showed that the normal growth of cucumber seedlings under salt stress was inhibited, while exogenous glucose on leaf surface could alleviate the growth inhibition induced by salt stress. Salt stress significantly increased malondialdehyde (MDA) content of cucumber leaves and the production rate of superoxide anion (O2∙-), decreased superoxide dismutase (SOD), peroxidase (POD) and ascorbate peroxidase (APX) activity. Under salt stress, the application of glucose significantly improve cucumber leaf SOD, POD and APX activity, reduced O2∙- production rate and MDA content. The results showed that exogenous glucose by regulating the expression of cucumber seedlings under salt stress of antioxidase encoding genes, improving the antioxidase activity, reducing oxidative damage, promoting seedling growth, so as to improve the salt tolerance of cucumber plants. Key words: salt stress; cucumber; glucose; antioxidant metabolism; gene expression 目 录 摘要 1 关键词 1 Abstract 1 Key words 1 引言 1 1材料与方法 1 1. 1幼苗培育及处理 1 1.1.1幼苗培育 1 1.1.2试验处理 1 1.2 测定方法 1 1.2.1生长指标测定 1 1.2.2抗氧化酶活性分析 1 1.2.3 MDA含量与O2∙-产生速率测定 1 1.2.4 黄瓜幼苗叶片总RNA的提取 1 1.2.5 黄瓜叶片RNA反转录 1 1.2.6 引物设计和PCR反应体系 1 1.3数据分析 1 2 结果与分析 1 2.1 外源葡萄糖对盐胁迫下黄瓜幼苗生长的影响 1 2.2 外源葡萄糖对盐胁迫下黄瓜幼苗叶片抗氧化酶活性的影响 1 2.3 外源葡萄糖对盐胁迫下黄瓜幼苗叶片O2∙-产生速率和MDA含量的影响 1 2.4 外源葡萄糖对盐胁迫下黄瓜幼苗叶片中的基因表达的影响 1 3 讨论 6 致谢 1 参考文献 1 图1 外源葡萄糖对盐胁迫下黄瓜幼苗叶片SOD、POD和APX活性的影响 5 图2 外源Glu对盐胁迫下黄瓜幼苗 O2∙-产生速率和 MDA含量的影响 5 图3 外源葡萄糖对盐胁迫下黄瓜叶片抗氧化酶编码基因表达的影响 6 (责任编辑：qin) |