Avaliação de características agronômicas e de produção de forragem e grãos de milho em diferentes densidades de semeadura e espaçamentos entre linhas

Abstract

Corn Zea mays L. is quite utilized for forage and grain production all over the world, due to its great productive potential and adaptability to the most different environments. Aspects related to the arrangement of plants in the area such as density, spacing and the canopy of the cultivar utilized, may determine forage and grain yield, in addition to other agronomic characteristics. Besides, reduction of spacing and increase of density may increase the crop's operational efficiency. The objective of this work was to investigate the behavior of corn hybrids of different leaf canopies, submitted to two interrow spacings and two densities of sowing, in two years of cultivation. The design utilized in the experiments (row spacings of 0.7 or 0.9 meters) was that of randomized blocks in a 3x2 factorial scheme to evaluate the performances of three hybrids (AG1051, AG9010 and DKB440) at two densities of sowing (55,000 and 75,000 plants.ha–1). The spacing reduction (from 0.90 m to 0.70 m) and the densities of sowing increase (fron 55,000 to 75,000 plants ha–1) provided an increase on both dry matter and grain yield, independently on the spacing being used. The AG1051 cultivar presented the highest dry matter yield, plant and first ear height, independently on the cultivation year and spacing. Cultivars AG9010 and DKB440 had the highest grain yield, independently on the densities of sowing or cultivation year.