Effects of soil properties and cultivar on cadmium accumulation in wheat grain

Cd accumulation in the grain of wheat cultivars grown on soils at seven experimental sites in the Austrian wheat zone was significantly affected by soil chemical characteristics and by cultivar. Multiple linear regression analyses indicate that about 80% of the variation in Cd accumulation may be explained by cultivar, total soil Ca, and organic carbon (OC). An additional 10% of the variation was correlated with Cl- and Ca2+ in the soil solution. Uptake of Cd increased with higher soil Cd content and higher Cl- concentrations in soil solution, but decreased at higher levels of OC and soluble Ca. Cd accumulation varied by a factor of up to 2.5 among cultivars. The highest Cd accumulation was found in some spring durum cultivars in soils containing relatively low total Cd (< 0.4 mg kg(-1)); at some sites the maximum permissible Cd concentrations in wheat grain (0.1 mg kg(-1)) was exceeded according to German regulations. Selecting low Cd-accumulating cultivars adjusting soil chemical conditions may provide alternatives to reduce Cd intake in human diet.