外源褪黑素通过调节抗氧化系统和降低镉的吸收来提高小白菜对镉的耐性
时间:2020-05-05 15:00 来源:毕业论文 作者:毕业论文 点击:次
| 摘要：本文采用室内水培的试验方法，研究外源褪黑素对镉胁迫下上海青小白菜种子萌发及相关生理指标的影响，以此探讨外源褪黑素在一定程度上能提高小白菜对镉的耐性。结果表明：外源褪黑素对镉胁迫具有一定的缓解作用，外源褪黑素能通过调节抗氧化系统和降低镉的吸收来提高小白菜对镉的耐性。当镉浓度为 20 μmol•L-1 时，添加100 μmol•L-1褪黑素，通过测量相关指标和数据处理，与单独用镉处理的对照组相比，可以发现褪黑素增强了镉胁迫下小白菜SOD,POD,CAT,APX等抗氧化酶活性，增加了光合色素的含量，减少了小白菜植物体内的活性氧，表明用外源褪黑素处理可提高小白菜的镉耐性。48434 毕业论文关键词：镉耐性；褪黑素；小白菜；抗氧化酶 Effects of Exogenous Melatonin on increasing Cadmium Tolerance in Chinese Cabbage by Adjusting Antioxidant System and Photosynthesis Abstract:In this paper, the effects of exogenous melatonin on seed germination and related physiological indexes of Brassica chinensis in Shanghai were studied by the method of indoor hydroponics to explore the exogenous melatonin to a certain extent, can improve the resistance of cadmium to cadmium.The results showed that exogenous melatonin had a certain effect on cadmium stress. Exogenous melatonin could improve the resistance of cadmium to cadmium by regulating the antioxidant system and decreasing the absorption of cadmium. When the cadmium concentration was 20 μmol•L-1, 100 μmol•L-1 melatonin was added. By measuring the correlation index and data processing, it was found that melatonin enhanced cadmium stress compared with the control group treated with cadmium alone The activities of antioxidant enzymes such as SOD, POD, CAT and APX in Chinese cabbage increased the content of photosynthetic pigments and reduced the reactive oxygen species in the plants of Chinese cabbage plants, which indicated that the treatment with exogenous melatonin could improve the cadmium tolerance of Chinese cabbage. Key words: cadmium tolerance; melatonin; cabbage; antioxidant enzyme 目 录 摘要1 关键词1 Abstract1 Key words1 引言1 1.材料与方法2 1.1材料培养 2 1.2材料处理2 1.3 测量相关指标3 1.3.1镉含量的测定3 1.3.2叶绿素含量的测定3 1.3.3超氧化物歧化酶（SOD）活性测定（氮蓝四唑光化还原法3 1.3.4过氧化物酶（POD）活性测定（愈创木酚法）4 1.3.5 过氧化氢酶（CAT）活性测定4 1.3.6抗坏血酸过氧化物酶（APX）活性的测定（缓冲液为K）4 1.3.7可溶性蛋白含量的测定（考马斯亮蓝染色法）5 1.3.8 O2-含量测定 5 1.3.9 H2O2含量测定5 2结果与分析5 2.1褪黑素对小白菜幼苗生长的影响5 2.2褪黑素对小白菜镉含量的影响6 2.3褪黑素对小白菜SOD酶活性的影响6 2.4褪黑素对小白菜POD酶活性的影响7 2.5褪黑素对小白菜CAT酶活性的影响7 2.6褪黑素对小白菜APX酶活性的影响8 2.7褪黑素对小白菜可溶性蛋白含量的影响8 2.8褪黑素对小白菜叶绿素含量的影响9 2.9褪黑素对小白菜过氧化氢含量（H2O2），超氧阴离子（O2-）的影响9 3.讨论10 3.1褪黑素能够减少活性氧的含量10 3.2褪黑素对光合色素的影响10 3.3褪黑素对抗氧化酶活性的影响10 3.4褪黑素能显著减少镉含量10 致谢10 (责任编辑：qin) |