AUTHOR=Gheith E. M. S. , El-Badry Ola Z. , Lamlom Sobhi F. , Ali Hayssam M. , Siddiqui Manzer H. , Ghareeb Rehab Y. , El-Sheikh Mohamed H. , Jebril Jebril , Abdelsalam Nader R. , Kandil Essam E. 

TITLE=Maize (Zea mays L.) Productivity and Nitrogen Use Efficiency in Response to Nitrogen Application Levels and Time

JOURNAL=Frontiers in Plant Science

VOLUME=13

YEAR=2022

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2022.941343

DOI=10.3389/fpls.2022.941343

ISSN=1664-462X

ABSTRACT=<p>Productivity of maize (<italic>Zea mays</italic> L.) and nitrogen use efficiency (NUE) as affected by nitrogen application levels and timing were studied. The experimental design was a three-replication randomized complete block design (RCBD). The first factor was nitrogen levels (122, 240, 288 and 336 kg N/ha) and the second factor was nitrogen timing (50% of N at sowing and 50% of N before the first irrigation; T<sub>1</sub>, 50% of N at sowing and 50% of N before the second irrigation; T<sub>2</sub> and 50% of N before the first irrigation and 50% of N before the second irrigation; T<sub>3</sub>). Results indicated that plant height, ear length, kernel weight, number of grains/rows, number of grains/ear and grain yields all increased significantly as nitrogen levels increased and the level of 336 kg N/ha significantly exhibiting the highest values in both seasons. In terms of nitrogen application time, maize yield parameters such as plant height, ear length, kernel weight/ear, number of grains/rows, number of grains/ear and grain yield were significantly affected by nitrogen timing, with the highest values obtained at T3 while the lowest values obtained at T1 in both seasons. The interaction had a significant impact on plant height and grain yield/ha, with the tallest plants, the highest yields and its components observed at 336 kg N/ha, with 50% of N applied during the first irrigation and 50% of N applied during the second. Furthermore, under the study conditions, NUE decreased dramatically as nitrogen levels increased and increased significantly as nitrogen application time changed.</p>