Silicon attenuates aluminum toxicity in young sugarcane by regulating enzymatic antioxidant capacity and osmolyte accumulation

Silicon (Si) supplementation can be a viable and friendly strategy strongly recommended to decrease aluminum (Al) toxicity in plants. Therefore, the purpose of this study was to determine the beneficial effect of Si on attenuating Al-induced stress in young sugarcane plants. Two-pot factorial (2 × 4) experiments were arranged in a Randomized Complete Block Design (RCBD) with four replications used for each sugarcane cultivar (‘CTC9002’ and ‘CTC9003′). The treatments included two levels of silicon supplementation (0 and 2 mM) and four aluminum concentrations (0, 10, 15, and 20 mM), which were assessed based on plant growth, biomarker production, enzymatic antioxidant activity, and osmolyte accumulation. Results indicated that Si supplementation improved the Al-stressed sugarcane growth due to decreasing the high levels of hydrogen peroxide and lipid peroxidation and by regulating antioxidant enzymatic capacity and osmolyte defense systems. Further, Si supplementation significantly improved the tolerance of the ‘CTC9003′ cultivar to Al-induced stress compared to ‘CTC9002’. Notably, our results strongly suggest that decreasing biomarker production, increasing enzymatic antioxidant activities, and regulating osmolyte accumulation by Si are associated with the detoxification of Al in sugarcane plants, indicating that supplying Si may be a key method for plants to cope with Al toxicity in acidic soils.