Distribuição de sementes de milho por discos dosadores em diferentes velocidades de operação

Abstract

Corn (Zea mays L.) is a crop that stands out in the Brazilian agricultural scenario, its economic importance is characterized by its varied forms of utilization. The use of modern corn hybrids and high plant densities become an efficient strategy to optimize productivity, where the spatial distribution of corn plants is closely associated with the sowing density. Horizontal disc seed distributors are widely used, the peripheral speed of disc rotation directly influences the way seeds are collected, conducted, individualized and ejected. Thus, one way to change the peripheral speed of a disc with pre-defined diameter, while maintaining the displacement speed and the density of seed deposition on the seeding line, is by changing the number of cores in the disc. Three disk configurations were tested, each containing 18, 28 and 38 cells, operating at three seeding speeds, 5, 7 and 9 km h-1 and distributing similar seed densities, using factorial design 3 (disks) x 3 (speed). The experiment was implemented in the year 2021, in a field located in the northwest region of the state of Rio Grande do Sul, municipality of Sete de Setembro, between the following coordinates 28° 6'27.69 "S and 54°30'8.73 "W. The evaluations were dedicated to the study of plant population density, longitudinal distribution (acceptable spacing, double spacing and gaps), and classification of the regularity of longitudinal distribution. The results obtained show that the increase in the number of cell reduces the peripheral speed, thus the prototype developed with 38 cell showed superior performance for a travel speed of 9 km h-1 and lower percentage of faulty spacings.