【作者】 陈苏雅；

【导师】 施国新；

【作者基本信息】 南京师范大学 ， 植物学， 2006， 硕士

【摘要】 本文以高等水生植物菹草（Potamogeton crispus）、伊乐藻（Elodea Canadensis L．）和水花生（Alternanthera philoxeroides（Mart．）Griseb．）为实验材料，利用光学摄影、生理生化测定、元素含量ICP-MS测定法（电感耦合等离子体质谱法）、透射电镜、扫描电镜等实验手段，对Cu²⁺胁迫下稀土元素铈(Ce³⁺)、钕(Nd³⁺)的单一及复合作用对水生植物形态、生理生化特性和亚细胞结构的影响进行了宏观与微观的分析研究。 试验结果表明，单一的Cu²⁺处理对水生植物的光合色素含量、保护酶系统活性、活性氧含量、膜脂过氧化产物含量、细胞超微结构等都有明显的毒害、破坏作用。其中，在Cu²⁺毒害下，水花生的叶绿素和可溶性蛋白含量下降，保护酶系统（POD、SOD、CAT）活性降低，O₂^．—产生速率和膜脂过氧化产物MDA含量上升，H₂O₂含量降低等。此时，加入适量单一与复合的稀土元素铈、钕之后，实验材料遭毒害的症状明显减轻，具体表现为光合色素含量、保护酶系统活性均有不同程度的提高，O₂^．—产生速率和膜脂过氧化产物MDA含量下降，H₂O₂含量升高，通过电镜观察发现细胞破坏程度有一定的缓和。在重金属元素Cu²⁺的毒害下，植物体内矿质元素的含量比正常值有很大程度的偏离，加入稀土元素后，偏离程度降低，促使植物体内的矿质元素含量趋于正常值。 本文讨论了稀土元素的最适作用浓度并初步研究了稀土元素缓解Cu²⁺对水生植物毒害的作用机理。总的看来，Ca³⁺和Nd³⁺的最适作用浓度为5-7.5mg·L^-1。Ce³⁺、Nd³⁺缓解重金属毒害的作用可能与调节蛋白质的表达及活性氧代谢有关。更多还原

【Abstract】 The resistance of toxic effects of Ce³⁺ and Nd³⁺ and their alternate action on aquatic plants Potamogeton crispus, Elodea Canadensis L. and Alternanthera philoxeroides （Mart.） Griseb. produces by heavy metals Cu²⁺ were measured by optics photography, physiological and biochemical indexes, concentration of elements and observations of election microscopy. We analyze the appearance, the physiological and biochemical characters, second-cellular structure of Potamogeton crispus, Elodea Canadensis L. and Alternanthera philoxeroides （Mart.） Griseb. macroscopically and microscopically. The results showed that heavy metal Cu²⁺ obviously damaged the content of chlorophyll, protein and H₂O₂, the activity of protective enzymes （SOD, POD, CAT）, the O₂^- generating rate, the content of MDA and the cell ultrastructural of Potamogeton crispus, Elodea Canadensis L. and Alternanthera philoxeroides （Mart.） Griseb.. The rare earth in an appropriate concentrations of Ce³⁺ and Nd³⁺ can rise up the activity of protective enzymes （SOD, POD, CAT）, the content of chlorophyll , protein and H₂O₂, and bring down the content of MDA, the O₂^- generating rate, protect the cell ultrastructural, lighten the toxic effects of Cu²⁺ on Potamogeton crispus, Elodea Canadensis L. and Alternanthera philoxeroides （Mart.） Griseb.. This thesis discussed the best concentrations of Ce³⁺ and Nd³⁺ that had the most obvious resistance of toxic effects, and researched the principle of the resistance of toxic effects Cu²⁺ on Potamogeton crispus, Elodea Canadensis L. and Alternanthera philoxeroides （Mart.） Griseb. by Cerium(Ce³⁺) and Neodymium(Nd³⁺) as well as their alternate action.更多还原