硒对镉胁迫下植物壶瓶碎米荠镉含量的影响

Effects of Selenium on Cadmium Content in Cardamine Hupingshanensis under Cadmium Stress

通过盆栽试验,设置单独Cd处理与Cd+Se复合处理(土壤镉浓度为0~200 mg kg^(-1)),研究不同处理下,壶瓶碎米荠(Cardamine hupingshanensis)植株的镉含量特征。结果表明:两种处理方式下,壶瓶碎米荠植株地上部和地下部镉含量随土壤中镉浓度升高而增加,呈线性相关。单独Cd处理,壶瓶碎米荠植株地上部镉含量变化范围为0.02~808.51 mg kg^(-1),地上部与地下部镉含量的平均比值为1.10,变化范围为1.05~1.23;富集系数的平均值为5.65,变化范围为4.04~7.85。Cd+Se复合处理,相同镉浓度处理下,壶瓶碎米荠地上部和地下部的镉含量均低于单独Cd处理组,最高浓度达到617.74 mg kg^(-1)和531.48 mg kg^(-1)。表明,壶瓶碎米荠是一种富集镉能力强的超积累植物,而添加硒可以降低其对Cd的富集,且不会影响其对Cd的吸收和向地上部转运的能力,在Cd污染场地的修复中前景较好。

A pot experiment was conducted to investigate the Cadmium(Cd) accumulation in Cardamine hupingshanensis after Selenium(Se) addition or soil combined addition of Se and Cd(0 to 200 mg kg^(-1)). The contents of Cd aboveground and underground showed linear correlation with soil Cd concentration. In the treatment of Cd single application, the Cd content aboveground was 0.02-808.51 mg kg^(-1), and the ratio of Cd content aboveground to underground varied from 1.05 to 1.23, with an average of 1.10. The enrichment coefficients ranged from 4.04 to 7.85,with an average of 5.65. Under the same Cd concentration, the Cd accumulation aboveground and underground was lower in the treatment of combined application of Se and Cd than in the treatment of single application of Cd, and reached the highest concentration of 617.74 mg kg^(-1) and 531.48 mg kg^(-1), respectively. Cardamine hupingshanensis was a Cd hyperaccumulator, and the addition of Se reduced the enrichment of Cd and had no effect on Cd uptake and transportation aboveground by Cardamine hupingshanensis. It would have better application prospects in remediation of Cd contaminated sites.