Influence of Plant Spacing and Varietal Selection on the Growth, Yield, and Productivity of Rice (Oryza sativa L.) in Jalingo and Karim Lamido, Taraba State, Nigeria

This study evaluated the influence of plant spacing and varietal selection on the growth, yield, and productivity of rice (Oryza sativa L.) under contrasting agro-ecological conditions of Jalingo and Karim Lamido, Taraba State, Nigeria. The experiment was conducted during the 2025 cropping season using a Randomized Complete Block Design (RCBD) in a 3 × 4 factorial arrangement with three replications. Treatments comprised three plant spacings (20 × 20, 25 × 25, and 30 × 30 cm) and four rice varieties (ITA 150, FARO 44, ABARE, and JAMILA). Data were collected on growth, yield, and yield-related traits and analysed using ANOVA, with means separated using Duncan’s Multiple Range Test at 5% probability. Variety, spacing, location, and their interactions significantly (P ≤ 0.05) affected most traits. ITA 150 consistently produced the tallest plants, largest leaf area, highest tiller number, longest panicles, heaviest 1000-seed weight (36.70 g), and highest grain yield (3,970 kg ha⁻¹). The 30 × 30 cm spacing produced the highest mean grain yield (3,895 kg ha⁻¹). Karim Lamido recorded higher mean grain yield (3,645 kg ha⁻¹) than Jalingo (3,115 kg ha⁻¹). The ITA 150 × 30 × 30 cm combination performed best across locations. ITA 150 at 30 × 30 cm is recommended for improved rice productivity in similar environments.