Abstract: Wild-type Arabidopsis thaliana Col-0 and iron transporter deletion mutant irt1 were used as experimental materials to study the mechanism of phosphorus deficiency. The following tests were applied: phosphorus-free plus cadmium-free treatment (-P-Cd), phosphorus-free plus cadmium treatment (-P+Cd), normal phosphorus supply without cadmium treatment (+P-Cd) and normal phosphorus supply plus cadmium treatment (+P+Cd). The results showed that under the condition of 40 μmol·L^-1 cadmium treatment, phosphorus deficiency treatment significantly raised relative leaf chlorophyll content and dry weight of wild-type Arabidopsis thaliana Col-0, and attenuated the toxicity of cadmium to wild-type Arabidopsis thaliana Col-0 compared with normal phosphorus supply. At the same time, phosphorus deficiency treatment reduced the cadmium content in Col-0 plants and inhibited the expression of iron transporter 1 (IRT1) in roots. Phosphorus deficiency treatment in the irt1 mutant also reduced cadmium content in plants, but the reduction was significantly lower than the results obtained for Col-0. Therefore, IRT1 gene played a role in inhibiting cadmium uptake and relieving cadmium toxicity.

Key words: cadmium toxicity, phosphorus deficiency, Arabidopsis thaliana iron transporter 1