Effect of Double Planting Density and Smaller Fertilization Rates on Grain Yield of Quality Protein Maize in a Clay-Sandysoil in Mvuazi

To evaluate the effect of seeding density associated with the different rates of mineral fertilizers on the agronomic performance of quality protein maize (QPM), a study was conducted in Mvuazi station during the 2017-2018 cropping season. Three planting densities (40,000; 53,333 and 106,666 plants·ha-1) and four mineral fertilizer rates with localized placement, namely: D1: 0 kg NPK + 0 kg Urea, D2: 100 kg NPK + 60 kg Urea, D3: 150 kg NPK + 90 kg urea, D4: 300 kg NPK + 120 kg Urea were tested. A split-plot design with three replicates was used and with fertilizer on man plots and plant density on secondary plots. Measures focused on growth and yield parameters. Data analysis showed that the double planting density (106,666 plants·ha-1) resulted in higher grain yield (6.05 t·ha-1) followed by the one of 53,333 plants·ha-1 (4.94 t·ha-1) when the highest fertilizer dose (D4) is applied. The two planting densities out-yielded the farmer’s planting density by 40 and 27% respectively at this fertilizer’s rate. Under D3 dose, the double planting density recorded the highest yield (5.65 t·ha-1) while the two others got similar yields (3.74 and 3.68 t·ha-1 respectively for 53,333 and 40,000, plants·ha-1). It is only under D2 and D1 where yields of all planting densities were similar (2.69, 1.91 and 2.90 t·ha-1 for D1; 4.13, 3.44 and 3.02 t·ha-1 for D2) for the 106,666, 53,333 and 40,000 plants·ha-1 planting densities respectively. Thus, the double planting density has been found to be recommendable for intensification of maize cultivation in Mvuazi when utilized at D3 or D4 rates with localized placement.