The effect of silicon on maize growth under cadmium stress

Abstract

The effects of silicon (Si) supply (0, 0.1, 0.5, 1.5, 3.0, and 5.0 mM Si) on maize seedling growth, Si and Cd accumulation, and thiol peptide synthesis under Cd stress conditions were studied. The addition of Si to the growth medium resulted in the significantly higher Si accumulation in plant tissues. The average values of growth parameters (root and shoot fresh weights and root net elongation rates) showed a beneficial role of Si on growth of non-Cd-treated plants, while there was no evidence that silicon mitigated Cd toxicity in maize seedlings. Cadmium exposure depressed plant growth and induced phytochelatin (PC) synthesis. The accumulation of Cd and PCs in roots significantly decreased with increasing Si concentrations in the nutrient solution; however, their accumulation in shoots was not changed in the presence of Si.