Evaluation of maize (Zea mays) genotypes under different nitrogen levels in a Trans-Gangetic Plains region

An experiment was conducted during rainy (kharif) seasons of 2021 and 2022 at the research farm of ICARIndian Agricultural Research Institute, New Delhi to study the effects of different genotypes and nitrogen levels on growth and yield of maize (Zea mays L.). Six maize genotypes (‘AH 4271’, ‘DKC 9164’, ‘PJMH 1’, ‘PMH 13’, ‘PC 4’ and Pusa Vivek QPM 9’ Improved (PV QPM 9-I) and 7 levels of nitrogen (0, 40, 80, 120, 160, 200 and 240 kg N/ ha) were evaluated using factorial randomized complete block design with two replications. Results showed that among the genotypes the ‘DKC 9164’ produced the highest kernel yield and resulted in maximum net returns (` 78.0 and 82.8 × 103 /ha) as compared to other genotypes. The growth parameters and yield increased with the increasing level of nitrogen from 0 to 240 kg/ha. Application of nitrogen @240 kg N/ha produced the maximum plant height, total number of leaves, leaf area index and stover as well as biological yield, whereas the maximum kernel yield and net returns (` 91.1 & 97.2 × 103 /ha) were obtained with 200 kg N/ha which was at par with 160 kg N/ha