A sufficient supply of silicon in the soil is required for healthy growth and higher productivity of the rice (Oryza sativa L.) crop. Applied Si seems to interact favorably with other nutrients (N, P, and K) and offers the potential to improve efficiency in terms of yield response. Silicon helps rice plants to resist biotic stresses (insect pests and fungal diseases) and tolerate abiotic stresses (Al, Fe, and Mn toxicities). It also helps reduce cuticular transpiration and, to some extent, crop lodging caused by excessive N supply (Savant et al 1997). It has been observed that rice plants in the most productive ecosystem of Varanasi region, which is identical to that of the northeastern plain zone of India, have started showing a tendency to lodge, even with the use of nonlodging, high-yielding, and short-duration varieties at the recommended fertilizer doses. It is therefore essential to understand the relationship between Si and N. This study aimed to determine the effects of N and Si levels on rice grown in Alfisols.