Effect of Row Spacing, Plant Density, Nitrogen Rate, and Planting Method on Maize (zea Mays L) Grain Yield

Narrow row spacing often results in increased plant density and reduced variability. This study was conducted to determine how narrow row spacing and increased plant density influence corn yield, harvest count, cob weight, stalk lodging and test weight. Two field experiments were conducted for two years, at Lake Carl Blackwell (Port silt loam) and Perkins (Teller sandy loam-fine-laomy, mixed, thermic Udic Argiustolls), Oklahoma. Fourteen treatments were evaluated at each location using a randomized complete block experimental design. Treatments included two different row spacing's (0.51m, 0.76m), four different plant densities (43,859 65,359 87,719, and 130,718 seeds/ha plants/ha), three different nitrogen (N) application rates (0, 60, 120 kg N/ha), two plant-to-plant spacing's (0.15m, 0.30m) and two different planting methods (Greenseeder hand planter vs Indigenous planter). Results were evaluated using grain yield, harvest count, cob weight, and stalk lodging as dependent variables. Narrow row spacing (0.51m) resulted in higher grain yields compared to the wide row spacing (0.76m) at both locations. This was likely due to increased plant population at the narrow spacing.Plant and Soil Scienc