矿质营养元素阻控植物镉积累:从机制到应用

Prevention of cadmium accumulation in plants by mineral nutrients: From mechanisms to applications

许多矿质营养元素能通过沉淀和吸附作用降低土壤中镉的有效性,同时也能与镉竞争细胞质膜上的转运体从而降低植物对镉的吸收。因此,通过合理的养分管理正确处理矿质营养元素和镉之间的关系,实现阻控作物对镉的吸收,被认为是一种费用低、周期短、效率高的技术措施。此外,通过其他农艺措施或分子育种手段调控矿质营养元素与镉之间的相互作用,也可能是2种降低作物镉积累的有效措施。本文主要根据近年来相关的研究进展,综述了矿质养分元素和镉之间的关系如何影响土壤中镉的有效性以及植物对镉的吸收。同时,以这些交互关系为基础,探讨了减控作物可食部位镉积累的策略。

Several mineral nutrient elements of plants can reduce cadmium（Cd） availability in soil by precipitation and adsorption, and decrease Cd absorption of plants by the competition between Cd and plant nutrients for the same membrane transporters. Nutrient management is one of the most important agronomic practices for better crop growth.Accordingly, it is regarded as a low cost, short period and high efficient way to alleviate Cd accumulation in crops by proper management of nutrients and proper treatment of the interactions between Cd and plant nutrients. In addition, other agronomic measures and molecular plant breeding, which could modulate the interactions between Cd and plant nutrients,might also be two relatively inexpensive and effective strategies to minimize Cd contamination in crops. The main objective of this review is to highlight how the interactions between mineral nutrient elements and Cd affect the availability of Cd in soil, and the Cd absorption of plants. Examples include that the competition between Fe, Ca, Zn, Mn and Cd uptake by root can decrease Cd levels in plants, and iron supply prevents Cd uptake by inhibiting iron-regulated transporter 1（IRT1）expression. The strategies of using these interactions to minimize Cd accumulation in the edible parts of crops were also focused in this review. For example, the application of P fertilizer can precipitate with Cd to reduce Cd uptake by plants. In addition, Si and Se fertilizer foliage application can decrease Cd translocation from roots to shoots in plants, thus reducing Cd accumulation in edible organs and improving food safety.