Nitrogen Use Efficiency in Bread Wheat Across Environments

Abstract

Experiments to evaluate the performance of 10 bread wheat genotypes with nitrogen deficiency and diagnose the optimal genotype for the appropriate environment commenced in the winter seasons, 2021-2022-2023 All the experiments had a randomized complete block design (RCBD) with split-plot arrangement. Nitrogen levels (0, 50, and 100 kg N ha -1 ) occupied the prime plots, with 10 wheat genotypes (T2, T3, S1, S2, S148, IPA99, Adana99, Rasheed, Buhooth-10, and Buhooth-22) allocated to the subplots with three replications in each location. The interaction of wheat genotypes, nitrogen levels, and locations revealed that genotype S2 with 50 kg N ha -1 at Baghdad showed the highest mean nitrogen use efficiency at 105.00 and 96.00 for 2021-2022 and 2022-2023, respectively. However, these values showed nonsignificant differences from the obtained values of wheat genotypes S148 and the IPA-99 during the second season, in the same location and fertilizer level, i.e., 92.87 and 90.00, respectively. Also, the genotype S2 gave the highest grain yield (6.53 t ha -1 ) with N2 fertilizer level in the Baghdad site, not differing significantly from two other wheat genotypes, S148 and IPA99 (6.13 and 5.85 t ha -1 , respectively) in the second season. The presented study authenticated that some wheat genotypes provided good yield under nitrogen stress (50 kg N ha -1 ), as there were no significant increases in grain yield when doubling the nitrogen level (100 kg N ha -1 ). Therefore, the study suggested these genotypes' cultivation with nitrogen deficiency to preserve a healthy environment and promote sustainable agriculture.