State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences, Northwest A&F University, Yangling, China.
Crit Rev Biotechnol. 2010 Mar;30(1):23-30. doi: 10.3109/07388550903208057.
Heavy metal pollution of soil is a significant environmental problem with a negative potential impact on human health and agriculture. Rhizosphere, as an important interface of soil and plants, plays a significant role in phytoremediation of contaminated soil by heavy metals, in which, microbial populations are known to affect heavy metal mobility and availability to the plant through release of chelating agents, acidification, phosphate solubilization and redox changes, and therefore, have potential to enhance phytoremediation processes. Phytoremediation strategies with appropriate heavy metal-adapted rhizobacteria or mycorrhizas have received more and more attention. In addition, some plants possess a range of potential mechanisms that may be involved in the detoxification of heavy metals, and they manage to survive under metal stresses. High tolerance to heavy metal toxicity could rely either on reduced uptake or increased plant internal sequestration, which is manifested by an interaction between a genotype and its environment.A coordinated network of molecular processes provides plants with multiple metal-detoxifying mechanisms and repair capabilities. The growing application of molecular genetic technologies has led to an increased understanding of mechanisms of heavy metal tolerance/accumulation in plants and, subsequently, many transgenic plants with increased heavy metal resistance, as well as increased uptake of heavy metals, have been developed for the purpose of phytoremediation. This article reviews advantages, possible mechanisms, current status and future direction of phytoremediation for heavy-metal-contaminated soils.
土壤重金属污染是一个严重的环境问题，对人类健康和农业有潜在的负面影响。根际作为土壤和植物的重要界面，在重金属污染土壤的植物修复中起着重要作用，其中微生物种群被认为通过释放螯合剂、酸化、磷酸盐溶解和氧化还原变化来影响重金属的迁移性和植物可利用性，因此有潜力增强植物修复过程。具有适当重金属适应根际细菌或菌根的植物修复策略越来越受到关注。此外，一些植物具有一系列可能参与重金属解毒的潜在机制，并且能够在金属胁迫下存活。对重金属毒性的高耐受性可能依赖于减少吸收或增加植物内部的螯合，这表现为基因型与其环境之间的相互作用。分子过程的协调网络为植物提供了多种金属解毒机制和修复能力。随着分子遗传技术的应用不断增加，人们对植物耐/积累重金属的机制有了更深入的了解，随后为了进行植物修复，开发了许多具有更高重金属抗性和更高重金属吸收能力的转基因植物。本文综述了植物修复污染土壤中重金属的优势、可能的机制、现状和未来方向。
