Abstract

The interactions between genotype and environment (GEI) and their stability concerning grain yield (GY), grain dry matter (GDM), and stover dry matter (VDM) yield were examined among eight genotypes across eight environments (seven in Ekiti State and one in Taraba State). The objective of the study was to identify promising maize genotypes suitable for both specific and broad adaptation, as well as to select the most favourable environments. A randomized complete block design with three replicates was employed to allocate genotypes to experimental units, utilizing a plant-to-plant spacing of 0.50 m and a row-to-row distance of 0.75 m. Calculations were made for GY, GDM, and VDM. An analysis of variance was conducted for each year, along with a combined analysis over years using the PROC GLM procedure of SAS version 9.2. The effects of GEI were evaluated using GEA-R (Version 4.1). A GE biplot was constructed based on Column Metric Preserving, tester-centered methodology, without scaling. Significant mean squares were detected for genotype, environment, and replication concerning GY, GDM, and VDM. The analysis revealed significant mean squares (P≤0.05) for GY, GDM, and VDM due to GEI. DMR-LSR-Y outperformed all other genotypes for GY, while it, along with SWAN-1-SR-Y and LNTP-Y, excelled in GDM. The top performers for VDM included OBA SUPER-6, DMR-LSR-Y, and BR-9928-DMR-SR-Y. Aiyetoro shows promise for identifying superior genotypes across GY, GDM, and VDM. The study recommends the inclusion of DMR-LSR-Y and LNTP-Y in multi- location testing in preparation for variety release, with DMR-LSR-Y identified as the ideal cultivar for VDM. Additionally, hybridization between DMR-LSR-Y and LNTP-Y may facilitate the development of segregating populations with improved GY, GDM, and VDM.