Impact of Silica Addition on Alleviating Cadmium Stress: Case Studies of Three Afforestation Tree Species Seedlings in Southern China

Cadmium (Cd) stress is becoming an increasing menace for plants, inducing a series of negative effect. Silicon (Si) plays important role in mitigating Cd plants. Here, we conducted one-year experiment with three kinds tree species seedlings (Schima superba, Chinese sweetgum, fir) and five levels treatments (0 mg·kg−1, 6 mg kg−1, 12 24 36 kg−1) or without 1 g kg−1 Si addition to investigate the mitigation effect on woody The results this study showed that triggered morphological physiological changes, inhibiting growth seedlings. Low concentrations treatment stimulated biomass production Schima superba sweetgum seedlings, whereas fir was not by treatment. stimulatory effects were also observed antioxidant enzyme (SOD, POD, CAT) activities MDA contents decreased rise treatments. Soil pH under stress. BCF values different fractions increase treatments, except leaf value sweetgum. root−to−stem TF all increased compared control, while root-to-leaf decrease. enhanced heights, ground diameter, parameters, production, content chlorophyll enzymes. Treatment significantly concentration after Si. Si-treated plants be lower than non-Si-treated ones. However, did affect root-to-stem