Silicon mediates the changes in water relations, photosynthetic pigments, enzymatic antioxidants activity and nutrient uptake in maize seedling under salt stress

摘要

It was hypothesized that silicon (Si) could regulate the salinity induced changes for adequate physiological adaptations against salt stress. Therefore, a pot study was conducted to assess the role of soil applied Si to improve the salt tolerance in maize seedling. Fifteen-day-old seedlings were subjected to four saline treatments with four replicates, namely control (no NaCl nor Si added), only Si (4mmolL(-1) Si), only salinity (40mmolL(-1) NaCl) and salinity + Si (40mmolL(-1) NaCl with 4mmolL(-1) Si) as salt concentration. Salt stress imposed negative impacts on plant growth attributes (root and shoot length, fresh and dry weight of root and shoot, seedlings biomass), water relations and photosynthetic pigments. In contrast, the supplementation of Si under stressed and normal growing conditions stimulated plant growth attributes, water relations and photosynthetic pigments. An increase in antioxidant enzyme activity was noted under stressed conditions, which was more pronounced in plants that experienced Si application. Silicon application under stressed conditions lowered the total soluble protein contents. It also regulated the ionic contents of the cell by restricting the sodium (Na+) and improving potassium (K+) contents. To conclude that soil applied Si was found a potential nutrient for reducing the negative effects of salinity and improving the growth of maize seedlings.