Volume 3 (Issue 2) 2023 Article 1

ABSTRACT:

Maize (Zea mays L.) plays a crucial role as a staple cereal globally supplying more than 30% of total dietary calories. In the Derived Savanna Agroecology zone of Nigeria, resource-constrained farmers involved in maize cultivation face the challenge of low soil nitrogen, leading to a notable reduction in maize grain yield. Hence, this study aimed to assess the phenotypic variations among selected maize cultivars and identify those exhibiting tolerance to low soil nitrogen with potential high grain yield across varying nitrogen environments. Seven maize cultivars assigned to subplots were evaluated across four distinct soil nitrogen environments (0, 30, 90, and 150 kg N ha-1) as the main plot at the Teaching and Research Farm of Ladoke Akintola University of Technology in Ogbomoso during the 2021 and 2022 main planting season. The experiment was arranged as splitplot, laid out in a randomized complete block design with six replicates. Agronomic and yield data were collected and subjected to analysis of variance. Rank summation index was used to determine superior cultivars and low nitrogen based index was used to identify cultivars tolerant to low soil nitrogen. The year effect, cultivar, soil nitrogen environments and their interactions mean squares showed significant (P < 0.01) differences for grain yield and other measured agronomic traits. The mean grain yields across soil nitrogen environments in two years ranged from 1729.6 to 4475.3 kg ha-1. Pioneer 30Y87 and Sammaz 52 were selected for grain yield superiority and tolerance to low soil nitrogen. These cultivars can be recommended to resource-limited farmers across the Derived Savanna Agroecology zone for improved growth and productivity.