O formato das sementes pode influenciar a plantabilidade do milho em dosadores pneumáticos?

Abstract

Corn (Zeamays L.) is of great economic importance for Brazilian agribusiness. Corn seeds have different characteristics in shape and specific mass according to the cultivar and place of seed formation on the corn cob. This research aimed to evaluate the influence of the shape of corn seeds, in the longitudinal distribution, with the use of a pneumatic doser. This study was conducted at the Agroforestry Machinery and Tire Testing Center (NEMPA), belonging to the Faculty of Agronomic Sciences, of the University Stateof São Paulo (UNESP), in the municipality of Botucatu-SP. Seeds from three commercial corn hybrids were used, in which the shape and sphericity index were evaluated. The experimental design used was completely randomized (DIC), totaling 15 treatments, composed of three varieties of corn, and five vacuum pressures in the doser. Our findings demonstrated that the seed shape influences the longitudinal deposition by the pneumatic feeder. The best results of seed deposition were obtained using the rounded V3 hybrid, which presented a higher index of acceptable spacing, less occurrence of flaws and doubles. The vacuum pressure of 7 kPa provided 98% of acceptable spacing for the V3 hybrid. For the V1 and V2 hybrids, the pressures of 4 kPa and 3 kPa demonstrated 96% and 87% of acceptable spacing, respectively.