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Water stress is one of the major abiotic factors affecting crop growth and development at every growth stages. Effects of water deficit on the vegetative growth stage of four maize varieties consisting of two Quality Protein Maize varieties (ILE1OB and ART98SW6OB) and two drought tolerant checks (TZPBSR and DTESTRSYN) were evaluated under the screen house conditions at the Institute of Agricultural Research and Training (I.A.R & T), Moor Plantation, Ibadan. Maize seeds were sown in 20 L plastic pots filled with 15 kg top soil, which were subjected to four watering regimes of 25, 50, 75 and 100% field capacities (FC). The experimental design was a 4 × 4 factorial fitted into CRD with four replications. Data were collected on days to germination, number of leaves per plant, leaf area, plant height, stem diameter, leaf extension rate, biomass yield and water use efficiency. The result showed that days to germination were prolonged as the moisture availability decreases, while water use efficiency increased as the moisture level reduced. Reduction in moisture availability caused significant reduction in the other evaluated parameters. At 25% FC DTESTRSYN was superior in leaf area, number of leaves per plant, days to germination and water use efficiency, TZPBSR had highest values for stem diameter and biomass yield, while ILE1OB was superior in plant height, stem diameter, leaf and stem extension rate. ILE1OB competes favourably with the drought tolerant checks and performed better than ART98SW6OB. Adequate moisture condition is fundamental for normal growth and development in maize crops.

Breeding for yield and quality requires the assessment of the seed metrics and vigour traits. This study, therefore, assessed the variability and inter-dependence of grain yield (GY), seed morphometric and vigour traits in hybrid maize. Seeds of 75 early maturing hybrid maize varieties were evaluated for morphometric traits and quality in four replicates. A field trial laid out in a randomised complete block design with three replicates was also conducted in Ibadan, Nigeria, to determine the grain yield of the hybrids. Data collected on the GY, seed dimension and quality were subjected to analysis of variance. The least significant difference was used to separate means. Relationships among the GY, seed morphometric and vigour traits were determined using correlation coefficients, while principal component (PC) analysis was performed for variability among the hybrids. Significant differences (P<0.001) were found in the GY, seed dimension and vigour traits. Four of the nine highest yielding hybrids had ECT higher than 30.0 ?sg-1 cm-1. The GY correlated with seed diameter (SDT) (0.40**), seed width (SWD) (0.36**), seed length (SLG) (0.35**), seed area (SAR) (0.30**) and seed vigour (SVI) (0.30**). The SAG correlated with SDT, SLG, seed thickness (STH) and SAR. All the seed vigour traits correlated with one another. The PC I explained GY, SDT, SWD, SLG, SAR and SVI, indicating their importance in GY improvement. Seed angle, length and diameter were versatile in maize varietal selection. Identified high yielding hybrids with seed morphometric and vigour qualities can be explored by seed companies as innovation in the seed production business.