Huang Hengliang, Li Mei, Rizwan Muhammad, Dai Zhihua, Yuan Yuan, Hossain Md Muzammel, Cao Menghua, Xiong Shuanglian, Tu Shuxin
College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, China; Hubei Research Center for Soil Remediation Engineering, Wuhan, 430070, China.
College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China.
J Hazard Mater. 2021 Jan 5;401:123393. doi: 10.1016/j.jhazmat.2020.123393. Epub 2020 Jul 6.
Silicon (Si) and selenium (Se), two beneficial elements that alleviate cadmium (Cd) toxicity, are important for agricultural production and human health. However, the effects and related mechanisms of Si-Se interaction on Cd toxicity alleviation are still poorly understood. Herein, a hydroponic experiment was employed to evaluate the effects of Si and Se alone and together, on the growth, Cd content, and biochemical parameters of Cd-treated rice plants. The results revealed that both Si and Se can effectively alleviate Cd toxicity, and a strong synergistic effect of Si and Se was observed. Simultaneous use of Si and Se significantly promoted rice plant growth, decreased malondialdehyde (MDA) content in both the roots and shoots, and reduced Cd translocation factor leading to a significant 73.2 % decrease in shoot Cd content. Additionally, Si-Se interaction increased glutathione (GSH) content, phytochelatin (PC) content and Cd distribution in root cell walls and organelles. Furthermore, the relative expression of OsHMA2 was down-regulated, while those of OsNramp1 and OsMHA3 were up-regulated. The above findings suggest that synergistic effect of Si and Se on Cd toxicity amelioration occurs mainly via regulating gene expression, sequestering Cd in the root cell walls and organelles, and reducing Cd transfer to the shoots.
硅（Si）和硒（Se）是两种能减轻镉（Cd）毒性的有益元素，对农业生产和人类健康都很重要。然而，硅 - 硒相互作用对减轻镉毒性的影响及相关机制仍知之甚少。在此，采用水培实验来评估硅和硒单独及共同作用对镉处理水稻植株生长、镉含量和生化参数的影响。结果表明，硅和硒都能有效减轻镉毒性，且观察到硅和硒有很强的协同效应。同时使用硅和硒显著促进了水稻植株生长，降低了根和地上部的丙二醛（MDA）含量，并降低了镉转运系数，导致地上部镉含量显著降低73.2%。此外，硅 - 硒相互作用增加了谷胱甘肽（GSH）含量、植物螯合肽（PC）含量以及镉在根细胞壁和细胞器中的分布。此外，OsHMA2的相对表达下调，而OsNramp1和OsMHA3的相对表达上调。上述研究结果表明，硅和硒对镉毒性的协同改善作用主要通过调节基因表达、将镉螯合在根细胞壁和细胞器中以及减少镉向地上部的转移来实现。
