| 青菜中镉的吸收和累积对硒的响应规律 |
| 摘要点击 1844 全文点击 835 投稿时间：2019-09-06 修订日期：2019-09-23 |
| 查看HTML全文
查看全文 查看/发表评论 下载PDF阅读器 |
| 中文关键词 青菜 硒 镉 转运 吸收动力学 |
| 英文关键词 pak choi selenium cadmium translocation uptake kinetics |
| 作者 | 单位 | E-mail | | 余垚 | 中国农业大学资源与环境学院, 农田土壤污染防控与修复北京市重点实验室, 北京 100193 | valcoyu@126.com | | 罗丽韵 | 中国农业大学资源与环境学院, 农田土壤污染防控与修复北京市重点实验室, 北京 100193 | | | 刘哲 | 中国农业大学资源与环境学院, 农田土壤污染防控与修复北京市重点实验室, 北京 100193 | | | 付平南 | 中国农业大学资源与环境学院, 农田土壤污染防控与修复北京市重点实验室, 北京 100193 | | | 李花粉 | 中国农业大学资源与环境学院, 农田土壤污染防控与修复北京市重点实验室, 北京 100193 | lihuafen@cau.edu.cn |
|
| 中文摘要 |
| 镉是一种有毒重金属，广泛种植的青菜却对镉有较强的富集能力.鉴于我国土壤的镉污染现状，消减青菜可食部位镉的累积有重要意义.硒可以调控植物对镉的吸收.通过3种青菜的水培硒、镉处理，以及硒影响下镉的吸收动力学，结果表明，3个浓度亚硒酸盐均使杭州油冬儿地上部镉含量显著降低50%左右；苏州青根和上海青的地上部镉含量则随硒水平提高而降低，但不显著.不同浓度亚硒酸盐可以降低青菜中镉转移系数，高浓度硒的抑制效果更明显；50 μmol·L-1亚硒酸盐使杭州油冬儿和苏州青根的镉转移系数显著降低了50%左右.亚硒酸盐可以提高青菜中铁、锰的含量，50 μmol·L-1亚硒酸盐使杭州油冬儿地上部铁含量提高了1/2.1 h吸收试验中，两种硒均显著提高了青菜对镉的吸收速率，并使Vmax提高了100%以上.因此，硒可以降低青菜可食部位的镉累积，但此效果依赖于品种，而且主要来源于硒对镉在植物内转运的影响，而非根表的吸收竞争. |
| 英文摘要 |
| Cadmium (Cd) is a highly toxic heavy metal. Brassica rapa (pak choi) is a vastly common vegetable, which readily accumulates Cd. Given the current conditions of Cd contamination in domestic soil, it is important to reduce Cd accumulation in the edible part of pak choi. Research has shown that selenium (Se) can regulate Cd uptake by plants. Cd accumulation (three cultivars) and Cd uptake kinetics in pak choi were investigated under hydroponic conditions. Results showed that the three levels of selenite significantly reduced Cd content in the Hangzhouyoudonger shoot by 50%, while the levels in Suzhouqinggen and Shanghaiqing shoots were not significantly decreased with elevated levels of selenite. Selenite reduces the Cd translocation factors, and higher levels had more obvious effects; 50 μmol·L-1 of selenite significantly decreased the factors by 50% in Hangzhouyoudonger and Suzhouqinggen shoots. Selenite also increased iron (Fe) and manganese (Mn) contents in pak choi, especially in the Hangzhouyoudonger shoot, where 50 μmol·L-1 increased the Fe content by approximately 50%. In the uptake kinetics of Cd, both selenite and selenate significantly increased Cd uptake rates and Vmax by over 100%. Therefore, Se could reduce Cd accumulation in pak choi. This also depended on the tested cultivar. Therefore, reduction effects of Se on the Cd content mainly stemmed from the alteration of Cd translocation in pak choi instead of the uptake competition between Cd and Se. |
|
|
|
