外源硅对甘蓝镉毒害的缓解效应
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