光合细菌对小麦幼苗镉铅离子胁迫缓解效应
时间:2019-09-17 12:53 来源:毕业论文 作者:毕业论文 点击:次
| 摘要：采用室内水培实验，研究了光合细菌对不同浓度处理的镉、铅离子胁迫下小麦幼苗生长的影响，探讨了光合细菌对小麦幼苗镉、铅离子胁迫的缓解效应。实验结果表明：镉、铅离子胁迫下小麦幼苗株高、根长以及幼苗叶片的可溶性蛋白含量、过氧化物酶含量、根系活力显著降低，而多酚氧化酶含量、丙二醛含量显著增加。低浓度的镉、铅离子对幼苗生长具有轻微的刺激作用，而高浓度的镉、铅离子对幼苗的生长具有抑制作用。光合细菌对镉、铅离子胁迫下的小麦幼苗具有一定的缓解作用。与镉、铅离子单独处理小麦幼苗相比，光合细菌可提高镉、铅离子胁迫下小麦幼苗根系活力、光合速率、可溶性蛋白含量、过氧化物酶含量，降低多酚氧化酶含量和丙二醛含量。光合细菌对30 mg/L氯化镉+12 mg/L硝酸铅胁迫下小麦幼苗生长的缓解作用最佳。39110 毕业论文关键字：光合细菌；镉；铅；缓解效应 Effect of Photosynthetic bacteria on Alleviating Cd2+, Pb2+ Stress of Wheat Seedling Abstract: Using hydroponic experiments to study the effects of photosynthetic bacteria on the growth of wheat seedlings under different concentrations of Cd2+, Pb2+ Stress. It was discussed that the effect of photosynthetic bacteria on the alleviation of Cd2+, Pb2+ stress in wheat seedlings. The results showed that: plant height, root length of wheat seedling and soluble protein content, peroxidase content, root activity of seedling leaves reduced significantly under the stress of Cd2+, Pb2+, but the content of PPO and MDA increased significantly. low concentrations of Cd2+, Pb2+ have slight irritation on seedling growth, but the high concentration of Cd2+, Pb2+ can inhibit the growth of wheat seedling. The photosynthetic bacteria had some mitigation effect on the wheat seedling under Cd2+, Pb2+ stress. wheat seedlings treated with Photosynthetic bacteria can improve root activity, photosynthetic rate, soluble protein content, peroxidase content of wheat seedling, and can induce PPO and MDA content under the stress of Cd2+, Pb2+ compare to that of wheat seedling treated with Cd2+, Pb2+ separately. When the alleviating effect of photosynthetic bacteria for wheat seedling treated with 30 mg/L CdCl2+12 mg/L Pb(NO3)2 was best. Key words: Photosynthetic bacteria; Cadmium; Lead; Alleviating Effect 目 录 摘要 1 引言 2 1 材料和方法 3 1.1 培养基、试剂和培养装置 3 1.2 材料培养及处理 4 1.3 测定项目与方法 5 1.3.1 形态指标 5 1.3.2 生理指标 5 1.4 数据分析 6 2 结果与分析 6 2.1 光合细菌对镉、铅离子胁迫下小麦幼苗形态指标的影响 6 2.2 光合细菌对镉、铅离子胁迫下小麦幼苗生理指标的影响 7 2.2.1 光合细菌对镉、铅离子胁迫下小麦幼苗光合参数的影响 7 2.2.2 光合细菌对镉、铅离子胁迫下小麦幼苗根系活力的影响 9 2.2.3 光合细菌对镉、铅离子胁迫下小麦幼苗可溶性蛋白含量的影响 9 2.2.4 光合细菌对镉、铅离子胁迫下小麦幼苗丙二醛含量的影响 10 2.2.5 光合细菌对镉、铅离子胁迫下小麦幼苗多酚氧化酶含量的影响 11 2.2.6 光合细菌对镉、铅离子胁迫下小麦幼苗过氧化物酶含量的影响 12 3 讨论 13 参考文献 15 致 谢 16 光合细菌对小麦幼苗镉、铅离子胁迫的缓解效应引言 近代工业的飞速发展、地下矿产的开发冶炼、大量废弃物的排放以及污灌、施用污垢和劣质化肥等农业活动，镉、铅等有害重金属不断进入农业环境中，造成了土壤和水体重金属污染。有关调查显示，我国大城市农产品重金属污染中镉、铅离子最为严重[1]。 (责任编辑：qin) |