Plant Density Optimisation in High-Yield Potential Maize Systems Under Irrigated Conditions in Northern Nigeria

This study optimises plant population density for achieving high yield potential in irrigated maize production systems in northern Nigeria, using experimental data from Kano, Kaduna, and Niger States to establish density-yield relationships for advanced hybrid varieties. As northern Nigeria expands irrigated maize production to meet rising feed grain demand, achieving high yields under controlled water supply requires revisiting plant density recommendations developed for rain-fed conditions, as high-yield potential maize hybrids bred for intensive management may respond differently to density than older varieties. This study conducts multi-site density trials over three seasons at research stations in the three states, testing six plant population densities from 40,000 to 110,000 plants per hectare using two advanced maize hybrids and one open-pollinated variety under full irrigation. Yield and yield components including ear number per plant, kernels per row, rows per ear, and hundred-kernel weight are measured. Quadratic regression models are fitted to density-yield data. Findings reveal that advanced hybrids achieve maximum yield at 80,000 to 90,000 plants per hectare, significantly higher than the standard extension recommendation of 53,000 plants per hectare for rain-fed production. The open-pollinated variety shows yield plateau at 66,000 plants per hectare and yield decline beyond this density. Maximum yield responses reach 10.4 tonnes per hectare for the best hybrid at optimal density. The study contributes original high-density yield response curves for northern Nigerian irrigated maize and recommends 80,000 plants per hectare as the revised density recommendation for irrigated hybrid maize.

Keywords: plant density, maize yield, irrigated production, northern Nigeria, hybrid varieties.