Effects of sodium silicate fertilizer on bacterial wilt control and lipid membrane peroxidation during tobacco growth

To clarify the effects and mechanisms of silicate fertilizer on tobacco resistance against bacterial wilt disease, field experiments were carried out with sodium silicate (Na₂SiO₃) on the disease incidence, disease index and lipid membrane peroxidation of Yunyan87. The results showed that Na₂SiO₃ application reduced the disease incidence and disease index on tobacco bacterial wilt disease. Comparing with the control, the disease incidence of tobacco seedlings treated with Na₂SiO₃ on the 90th and 100th days after transplanting decreased by 13.14% and 12.08%, and the disease index by 23.34% and 21.26%. The difference between the treated tobacco and the control was statistically significant. With the proceeding and depravation of bacterial wilt disease, the contents of H₂O₂ and malondialdehyde (MDA) in tobacco leaves as well as membrane permeability and K⁺ leakage increased. Na₂SiO₃ application significantly decreased the contents of H₂O₂ and MDA, alleviated the membrane damage of tobacco, improved catalase activity, by significantly reducing the activities of superoxide dismutase and peroxidase.