Silicon the Non-Essential Beneficial Plant Nutrient to Enhanced Drought Tolerance in Wheat

Present water scarcity is a severe problem and cause of deterioration in quality and productivity of crops to reduce crop yield in arid and semi-arid regions. Silicon is known to better the deleterious effects of drought on plant growth and development. Silicon (Si) found to be an agronomically important fertilizer element that enhances plant tolerance to abiotic stresses (Liang et al., 2005). Silicon also known to increase drought tolerance in plants by maintaining plant water balance, photosynthetic efficiency, erectness of leaves and structure of xylem vessels under high transpiration rates due to higher temperature and moisture stress (Hattori et al., 2005). Similarly, Gong et al., (2003 and 2005) observed improved water economy and dry matter yield of water under application of silicon. A number of possible mechanisms were proposed through which Si may increase salinity tolerance in plants, especially improving water status of plants, increased photosynthetic activity and ultra-structure of leaf organelles. The stimulation of antioxidant system and alleviation of specific ion effect by reducing Na uptake were also drought tolerance mechanisms in plants exposed to silicon application (Liang et al., 2005).