外源硅对甘蓝镉毒害的缓解效应
时间:2020-05-05 14:50 来源:毕业论文 作者:毕业论文 点击:次
| 外源硅对甘蓝镉毒害的缓解效应摘要：本实验以耐镉(Cd)性不同的2个甘蓝品种（绿丰—Cd敏感性、牛心—耐Cd性）为实验材料，研究了外源硅（Si）对Cd胁迫下甘蓝生物量、地上部和地下部中Cd含量、叶片和根系中MDA含量、H2O2含量以及抗氧化酶活性的影响。结果表明：与Cd单独处理相比，外源Si同时处理后，2个甘蓝品种的生物量均显著增加，其中，绿丰的生物量增加幅度明显大于牛心；另外，2个甘蓝品种地下部Cd含量显著升高，而地上部的Cd含量显著降低；与单独Cd处理相比，叶片和根系MDA和H2O2含量均显著降低，其中，绿丰MDA和H2O2含量下降幅度大于牛心;与单独Cd处理相比，外源Si缓解处理使2个品种叶片SOD活性升高；另外，在根系中，绿丰SOD活性上升而牛心SOD活性降低；在Cd胁迫下，2个甘蓝品种根系中CAT和叶片中APX活性均显著降低，外源Si同时处理后，酶活性均显著升高；与对照相比，单独Cd处理下，2个品种的营养元素（Si、Ca）显著下降，外源Si同时处理后显著升高。总之，外源Si处理，提高了Cd胁迫下甘蓝植株体内抗氧化酶的活性，降低了Cd向植株地上部的转运，从而提高了甘蓝植株的耐Cd性。48427 毕业论文关键词：甘蓝（Brassica oleracea L.）、镉（Cd）、硅（Si）、干重、抗氧化系统 The effects of exogenous Silicon alleviate Cadmium stress in cabbages Abstract：In order to study the effect of Silicon alleviate Cadmium stress in cabbages（Brassica oleracea L.）, several parameters on biomass, Cd uptake, MDA content, H2O2 content and antioxidant enzyme activities were compared between the variety Lüfeng (Cd-sensitive) and Niuxin(Cd-resistance). The results showed: (a) Cd+Si treatment restored the Cd-inhibited growth. Exogenous Si for both varieties caused a significantly increased in the dry weight of plant, with a much more severe response in the Cd-sensitive varieties. (b) Exogenous Si obvisiously restrained the transportion of Cd from roots to shoots of two varieties. (c) Exogenous Si decreased the contents of malondialdehyde (MDA) and hydrogen peroxide(H2O2) in two varitieties, and the decreased of Lüfeng is higher than that of Niuxin. (d) After Cd+Si trearment, SOD activity of two varitieties in shoot increased. What’s more, SOD activity of Lüfeng in root increased and decreased in root of Niuxin. After Cd trearment, CAT activity in root and APX activity in shoot significantly decreased. The activities of antioxidant enzymes in two varitieties rised after Cd+Si treatment. (e) After Cd trearment, the balance of nutrient elements (Si, P, Ca, Mg) was obviously destroyed, and exogenous Si alleviated Cd stress in two varieties. In short, after Cd+Si treatment, the activities of antioxidant enzymes rised, the transportion of Cd from roots to shoots restrained, then the cadmium resistance of the plant was improved. Key words: Cabbage（Brassica oleracea L.）; Cadmium; Silicon; Dry weight; Antioxidant system 目 录 摘要 1 关键词 1 引言 2 1 材料与方法 2 1.1实验材料 2 1.2实验设计 2 1. 2. 1甘蓝的培养 2 1. 2. 2实验处理 2 1.3测定项目与方法 3 1. 3. 1干重 3 1. 3. 2 元素含量的测定 3 1. 3.3 MDA、H2O2和 3 1.3.3 抗氧化相关酶（SOD、CAT、APX）活性的测定 3 1. 4数据处理和作图 3 2结果与分析 3 2.1 Si对Cd胁迫下甘蓝生物量的影响 4 2.2 Si对Cd胁迫下甘蓝Cd吸收的影响 4 2.3 Si对Cd胁迫下甘蓝MDA含量的影响 5 (责任编辑：qin) |