Abstract Cadmium is a non-essential trace metal, which is highly toxic to nearly all living organisms. Soil pollution causes Cd contamination of crops, thereby rendering plant products responsible for the chronic low level Cd over-exposure of numerous populations in the world. For this reason, Cd accumulation in plants has been studied for about five decades now. The research first focused on the relationships between plant and soil Cd levels, on the factors of the metal availability in soil, as well as the root uptake processes. Cd distribution in plant organs was also investigated, first using a macroscopic and eco-physiological approach, and then with the help of molecular biology tools, at both tissue and cell scales. Cadmium has no biological function and hijacks the transport pathways of micronutrients such as Fe, Mn, or Zn, in order to enter the plant through the roots and be distributed to all its organs. The study of the genes that control the influx and efflux of the Cd2+ ion in the cytosol, vacuoles, and vascular tissues has significantly contributed to the understanding of the metal root uptake and of its transfer to the aerial parts. However, the mechanisms responsible for its distribution to the different above-ground tissues and specially to fruits and seeds have yet to be clarified. This review summarizes current knowledge in order to present a detailed overview of Cd transport and storage, from the rhizosphere to the different organs and tissues of the plant.

中文翻译：

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植物中镉的积累机制

摘要 镉是一种非必需的微量金属，对几乎所有生物都有剧毒。土壤污染导致作物受到镉污染，从而使植物产品成为世界上许多人口慢性低水平镉过度暴露的原因。出于这个原因，植物中 Cd 的积累已经研究了大约 50 年。该研究首先关注植物和土壤 Cd 水平之间的关系、土壤中金属有效性的因素以及根系吸收过程。还研究了植物器官中 Cd 的分布，首先使用宏观和生态生理学方法，然后在分子生物学工具的帮助下，在组织和细胞尺度上进行研究。镉没有生物学功能，它会劫持微量营养素如 Fe、Mn 或 Zn 的运输途径，以便通过根部进入植物并分布到其所有器官。对控制细胞质、液泡和维管组织中 Cd2+ 离子流入和流出的基因的研究对了解金属根吸收及其向地上部分的转移做出了重大贡献。然而，负责其分布到不同地上组织，特别是果实和种子的机制尚未阐明。本综述总结了当前的知识，以便详细概述从根际到植物不同器官和组织的 Cd 运输和储存。和维管组织对理解金属根吸收及其向地上部分的转移做出了重大贡献。然而，负责其分布到不同地上组织，特别是果实和种子的机制尚未阐明。本综述总结了当前的知识，以便详细概述从根际到植物不同器官和组织的 Cd 运输和储存。和维管组织对理解金属根吸收及其向地上部分的转移做出了重大贡献。然而，负责其分布到不同地上组织，特别是果实和种子的机制尚未阐明。本综述总结了当前的知识，以便详细概述从根际到植物不同器官和组织的 Cd 运输和储存。