Silicon (Si), although not considered as an essential element for plants in general, can ameliorate the phytotoxicity induced by excess metal(loid)s whether non-essential (e.g. Cd, Pb, Cr, Al, As, and Sb) or essential (e.g. Cu, Ni, and Zn). The Si-enhanced resistance allowing plants to cope with this type of abiotic stress has been developed at multiple levels in plants. Restriction of root uptake and immobilization of metal(loid)s in the rhizosphere by Si is probably one of the first defence mechanism. Further, retention of elements in the root apoplasm might enhance the resistance and vigour of plants. At the cellular level, the formation of insoluble complexes between Si and metal(loid)s and their storage within cell walls help plants to decrease available element concentration and restrict symplasmic uptake. Moreover, Si influences the oxidative status of plants by modifying the activity of various antioxidants, improves membrane stability, and acts on gene expression, although its exact role in these processes is still not well understood. This review focuses on all currently known plant-based mechanisms related to Si supply and involved in amelioration of stress caused by excess metal(loid)s.

中文翻译：

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硅对植物中金属（金属）胁迫的缓解机制研究进展。

硅（Si）虽然通常不被认为是植物的必需元素，但无论是非必需（例如Cd，Pb，Cr，Al，As和Sb）还是必需，都可以改善由过量金属（金属）诱导的植物毒性。 （例如Cu，Ni和Zn）。在植物中已开发出使植物应对这种非生物胁迫的硅增强抗性。Si限制根吸收和根际固定化金属（金属）可能是第一个防御机制之一。此外，将元素保留在根际质朴中可能会增强植物的抗性和活力。在细胞水平上，Si和金属（金属）之间不溶性复合物的形成及其在细胞壁中的储存有助于植物减少可用元素的浓度并限制同质吸收。此外，硅通过修饰各种抗氧化剂的活性来影响植物的氧化状态，改善膜的稳定性，并影响基因表达，尽管其在这些过程中的确切作用尚不清楚。这篇综述着重于所有当前已知的与硅供应有关的植物性机制，并参与减轻由过量金属（金属）引起的应力。