Comparative analysis of cadmium uptake and distribution in contrasting canadian flax cultivars

OBJECTIVE: Humans consume low quantities of cadmium (Cd), a non-nutritive and potentially toxic heavy metal, primarily via the dietary intake of grains. A trial experiment was conducted to investigate physiological and developmental differences in Cd content in four flax cultivars (‘AC Emerson’, ‘Flanders’, ‘CDC Bethune’, and ‘AC McDuff’) as part of a study to provide information that will assist in the breeding of low Cd-accumulating flax cultivars. Our objective was to identify varietal differences in the uptake and distribution of Cd in various tissues among flax cultivars grown in naturally Cd-containing soil in a controlled environment. RESULTS: Cadmium concentration was dependent on genotype, developmental stage, and tissue type, as well as their interaction. Cadmium concentration was higher in roots and leaves, relative to all other tissues, with a general trend of decreasing Cd content over time within leaves and stems. Notably, the concentration of Cd was higher in ‘AC Emerson’ relative to ‘AC McDuff’ across tissues and ages, including the seeds, while the concentration of ‘Flanders’ was higher than in ‘AC McDuff’ in seeds and other reproductive organs but similar in roots and leaves. The results suggest varietal differences in the mechanisms that determine Cd content in seeds.