Department of Agronomy, Institute of Agricultural Sciences, B.H.U., Varanasi - 221 005, India.
1Central Research Laboratory, Department of Soil Science, U.P. College, Varanasi-221 002, India
Present trends toward intensive rice cultivation by growing more than one crop of fertilizer responsive high-yielding cultivars in a year may result in a decrease in plant available Si in the soil. Silicon has been described as being absorbed actively and passively by roots. Large amount of Si as monocilicic acid is absorbed by the rice plant. Si nutrition has direct and indirect beneficial effects on rice growth largely due to its unique physiological role. Silicon promoted growth attributes, photosynthetic activity of the lower leaves and improved leaf and stalk erectness of rice. Silicon improved the plant resistance to biotic and abiotic stresses such as soil aluminium (AI) manganese (Mn) and iron (Fe) toxicities alleviation, plant pests and disease resistance and increased phosphorus availability. Application of Si with nitrogen has been found to raise the optimum nitrogen dose from its existing level due to its synergistic effect and addition of nitrogen enhances lodging because of enhanced plant growth while Si as well as high N has greater resistance to lodging. The review covers the relationship of silicon to rice crop production, including growth, yield attributes, yield, quality and nutrient uptake.
