Performance of Maize Hybrids for Grain Yield Under Different Planting Arrangements

The aim of this study was to evaluate the agronomic performance of eight maize hybrids under different plant densities for grain yield in the North and Northwest regions of Rio de Janeiro State, Brazil. Maize productivity is strongly influenced by planting density, which affects light interception, resource competition, and grain yield. Understanding the optimal density for specific hybrids is essential to maximizing production under varying environmental conditions. The hybrids were evaluated in two locations (Campos dos Goytacazes and Itaocara) using four plant densities (50,000; 66,667; 83,333; and 100,000 plants ha−1). The experimental design was a randomized complete block with three replications in a split-plot arrangement. Traits evaluated included plant height, ear height, ear length and diameter, 100-grain weight, and grain yield. Planting density significantly affected ear length, ear diameter, 100-grain weight, and grain yield, with higher densities generally reducing morphological traits but increasing overall yield. No significant genotype × density interaction was detected, but some hybrids, such as UENF 506-16 and UENF 506-11, performed better at specific densities, standing out for productivity and economic return. These results indicate that increasing plant density can be an effective strategy for maximizing maize yield in the studied environments.