Effect of Nitrogen and Silica on Growth and Yield of Paddy (Oryza sativa L.) Variety CO 51

World agriculture is facing increasing demand due to multiple challenges. The biggest challenge is to attain food security in the ever increasing growing population. Rice (Oryza sativa L.) is a staple food crop for half of the world's population and one of the world's most significant food crops. Farmers must produce more rice with enhanced quality in order to ensure food security in rice-consuming countries across the world. Rice (Oryza sativa L.) is considered to be a Si accumulator plant and tends to actively accumulate Si into tissue up to concentrations of 5% or even higher. The present study aimed to use different forms of N and Si sources at different levels to improve the growth traits contributing to the increase yield of rice. A pot experiment was conducted in glasshouse, TNAU, Coimbatore to assess the response of nitrogen and silica on paddy during October 2020 – January, 2021. The treatments comprised of the two factors, nitrogen and silica with three replications. The growth parameters like plant height, number of tillers per plant and total dry matter production were recorded at all stages and yield traits at harvest stage. The treatment, T11 - N2S2 (53.4 and 110.2 g pot-1 respectively) significantly enhanced the grain yield (34%) and straw yield (40%) than control in the pot experiment. Highest growth and yield parameters were recorded with application of combined fertilization of nitrogen and silica (T11-N2S2) which comprises150 kg ha-1of urea and 200 kg ha-1 of calcium silicate compared to control.