Efeito de espaçamentos e épocas de plantio sobre caracteres agronômicos de híbridos de milho

Abstract

Every year, new corn hybrids and climatic and environmental variations in the different Brazilian regions require from research organizations, private companies, and farmers alternate management practices to improve corn productivity and profitability. As a result of spatial arrangement discussions and related corn growing recommended techniques, special attention has been given to row spacing reduction. As an example, in the Brazilian Central Plateau, about 50% of corn production has been harvested from double cropping after soybeans. In this situation, the same machinery adjustments used for soybeans are used for double cropped corn, reducing the time required between harvesting and sowing operations. Three experiments were conducted to study the effect of row spacing on corn hybrids agronomic characteristics in the Goiania region, Goias State, evaluating five commercial hybrids in four row spacings and three sowing dates. The experimental design was a 5x4 factorial in randomized blocks with four replications. Row spacing did not significantly affect plant height, ear, stalk and corncob diameter, yield, stalk rot and lodging. The hybrids behavior was significantly different in the four row spacings. The higher yields were obtained in the third planting date under irrigation.