Dissecting the Physiology of Cadmium Translocation and Accumulation in Wheat Grains.

Cadmium, a non-essential metal and a chemical analog of zinc accumulates in edible portions of crop plants and therefore the main source of cadmium in humans is through plant foods. Cadmium has the tendency to accumulate in grain crops such as wheat in elevated concentrations. This has led to strict international limits on the level of cadmium in foods, such as 0.2mg KgCd^-1 in cereals and legumes. Studies in near-isogenic wheat lines differing in grain cadmium content have shown that the lines differ in root-shoot partitioning of cadmium. The addition of zinc to soils has been reported to affect cadmium accumulation in crops. However the effect of zinc on cadmium accumulation is unclear. The main objective of this study is to determine if Zn fertilization has an effect on the translocation of Cd and Zn in wheat isolines differing in grain cadmium concentrations. Partitioning experiments in different isolines of wheat grown in different concentrations of Cd (0.5μM) and Zn (2μM and 10μM) will help in determining if Zn reduces the Cd uptake or translocation of cadmium into the shoots and ultimately to the developing grain. Results of partitioning and accumulation of cadmium and zinc in these different isolines will be presented.