Silicon-mediated alleviation of Mn toxicity in Cucumis sativus in relation to activities of superoxide dismutase and ascorbate peroxidase

The effects of exogenous silicon on plant growth, activities of superoxide dismutase, guaiacol peroxidase, ascorbate peroxidase, dehydroascorbate reductase, glutathione reductase and catalase, and concentrations of ascorbate and glutathione were investigated in cucumber (Cucumis sativus L.) plants treated with excess 600 μM Mn. The alleviation of Mn toxicity by Si was related to a significant increase in the activities of SOD, APX, DHAR and GR and the concentrations of ascorbate and glutathione.