Uptake, translocation and accumulation of cadmium in plant

Cadmium (Cd) is highly toxic to plants even at low concentrations and influences plant growth and development. Research on Cd transport in plants is highly vital in phytoremediation and environmental restoration. Soil micro-environment greatly influences Cd²⁺ absorption in plants. Cd²⁺ is selectively absorbed through root cell wall and most of it remains in the cell wall while a small fraction enters the cell by diffusion or active transport in the membrane and yet another small amount of Cd²⁺ is deposited in cell vacuole. Cd²⁺ is transported from the root to the shoot system through xylem vessels. In the shoot system, most of the Cd remains in the vacuoles of shoots and leaves, while a few is deposited in the cell wall and cytoplasm. In the period of seed development, Cd can also be transferred in the seed through the phloem, and the accumulated Cd in seeds hardly moves to other parts of the plant. Furthermore, Cd can be easily transferred to animals and man through food chain. This paper provides an overview of Cd uptake from the soil, and its translocation and accumulation in plants and the metabolic system of animals.