Variation in cadmium accumulation in spring wheat cultivars: uptake and redistribution to grain

Abstract

Background and aims: Due to the risks of cadmium (Cd) toxicity in the human diet, there is need to develop low-Cd wheat, since wheat is one of the most consumed food worldwide. The objective of this study was to investigate variations in Cd accumulation in grain among spring wheat (Triticum aestivum L.) cultivars, and the relationships between root morphology and Cd accumulations in grain and shoot biomass, to better understand Cd accumulation mechanisms in grain. Methods: Grain yield, shoot biomass, Cd concentration and content, and root characteristics were measured in multiple spring wheat cultivars in a greenhouse experiment with and without Cd amendments, and in a field experiment conducted in un-contaminated soils at two locations in southeastern Idaho, USA. Results: Cultivars ‘LCS Star’ and ‘UI Pettit’ had greater root morphological parameters (e.g., root length, surface area, and volume), and concentrations and contents of Cd in grain than ‘UI Platinum’ and ‘UI Stone’. Cadmium concentration and content in grain were positively correlated with those in shoot biomass, and root morphological parameters (e.g., length, surface area, and volume). Conclusions: Differences in root morphological characteristics between spring wheat cultivars is an important factor that contributes to Cd accumulation in grain.