Fe deficiency induces Cu uptake and accumulation in Commelina communis

Tissue concentrations of some mineral elements appeared to be influenced by plant Fe status. The influence of Fe deficiency on Cu uptake and accumulation in Commelina communis, and the relationship between Cu uptake and root Fe(III) chelate reductase (FCR) activity were investigated in this study. The results showed that Cu accumulation in C. communis was increased with the drop of Fe concentration in nutrient solution. Cu uptake in C. communis was significantly enhanced by Fe deficiency. Cu uptake in Fe-deficient plants were still higher than that of Fe-sufficient plants when P-type ATPase inhibitor Na3VO4 was added in the solution, which demonstrated that Fe deficiency induced stimulation of the plasma membrane H+-ATPase did not play a role in the enhanced Cu uptake. Fe and Cu deficiency could induced root Fe(III) chelate reductase activity in C. communis. Both Fe(III) chelate reductase activity aud Cu concentration in roots inhibited distinctly by cycloheximide, a kind of protein synthesis inhibitor. In the time course of Fe deficiency, there simultaneously appeared Cu concentration and FCR activity peaks in roots at day 9. All above evidences demonstrated Cu uptake and accumulation in C. communis were probably related to the root FCR activity. (C) 2004 Elsevier Ireland Ltd. All rights reserved.