SEMEADURA DE FEIJÃO VAGEM COM DIFERENTES DISCOS E VELOCIDADES OPERACIONAIS

Abstract

World string beans yield reached 1,387,667 tons in 2019 in an area of 1,464,380 ha in Brazil. Its propagation way can be by the mechanized sowing. This paper aimed to evaluate the string beans sowing quality using different metering discs (28 and 72 holes) in a precision seeder operating at different speeds (3.6, 5.9, and 8.5 km h-1). This study was carried out at the Goiano Federal Institute, Morrinhos Campus, in the municipality of Morrinhos, Goiás State (GO), Brazil, in an area irrigated via central pivot. The experiment was set up with a randomized block design composed of a 3 x 2 factorial scheme (3 speeds and 2 dosing discs), making up 6 treatments with 5 replicates, totaling 30 experimental units. Each plot had an area of 10 m² (5 x 2 m). Planting quality parameters were determined and evaluated by the Tukey test at 5% probability, and statistical process control was performed by control charts. Regression analysis was carried out for the seedling emergence index. Results indicated that the increase in speed contributed to major irregularities in the seed distribution, in which the speed of 8.5 km h-1 was the one that provided values with less uniformity, causing a greater number of spacing failures. The speed combination of 3.6 km h-1 with 72-hole discs showed a better linear distribution of seeds with points closer to the ideal spacing of 9.3 cm among seeds. This speed also showed the lowest plant emergence speed index with the 28-hole disc.