Nitrogen (N), the building block of plant proteins and enzymes, is an essential macronutrient for plant functions. A field experiment was conducted to investigate the impact of different N application rates (28, 57, 85, 114, 142, 171, and 200 kg ha−1) on the performance of spring wheat (cv. Ujala-2016) during the 2017–2018 and 2018–2019 growing seasons. A control without N application was kept for comparison. Two years mean data showed optimum seed yield (5,461.3 kg ha−1) for N-application at 142 kg ha−1 whereas application of lower and higher rates of N did not result in significant and economically higher seed yield. A higher seed yield was obtained in the 2017–2018 (5,595 kg ha−1) than in the 2018–2019 (5,328 kg ha−1) growing seasons under an N application of 142 kg ha−1. It was attributed to the greater number of growing degree days in the first (1,942.35°C days) than in the second year (1,813.75°C). Higher rates of N (171 and 200 kg ha−1) than 142 kg ha−1 produced more number of tillers (i.e., 948,300 and 666,650 ha−1, respectively). However, this increase did not contribute in achieving higher yields. Application of 142, 171, and 200 kg ha−1 resulted in 14.15%, 15.0% and 15.35% grain protein concentrations in comparison to 13.15% with the application of 114 kg ha−1. It is concluded that the application of N at 142 kg ha−1 could be beneficial for attaining higher grain yields and protein concentrations of wheat cultivar Ujala-2016.
KW - Economical yield; growing degree days; nitrogen; Ujala-2016; wheat DO - 10.32604/phyton.2023.025781