The spray deposition and losses of pesticide application were evaluated for the soybean crop. In this study two sprayers were used: the air-assisted sprayer (Vortex-Jacto) and the conventional non-assisted sprayer (Condor M12-Jacto), both with API 110-1.5 flat fan nozzles operating at 30 psi working pressure, with 0.5 m spacing on the boom. Volume rates were 100 L ha-1 for both equipments. A completely randomized experiment with four replicates was carried out in the field. For all treatments, the ground speed was 6 km h-1 and boom height was 0.40 m above canopy. Spray deposition and losses were evaluated using 2% KCl and NaCl solutions in air-assisted and conventional non assisted sprayers. Deposition evaluations were performed on leaves from the upper, medium and lower parts of the soybean plant. Spray losses to the soil were evaluated using artificial targets (square wood board) that were distributed on the soil surface at intervals of 3 m from each other. Drift was evaluated through these targets and pipe cleaners fixed on rods placed at the left and right sides at the crop. There were no significant differences in the deposition for both equipments in the upper parts of the plants, but there were differences in the medium and lower parts, showing an advantage of the air-assisted sprayer. Drift and losses were larger for the conventional non assisted sprayer at similar meteorological conditions.
Glycine max; mechanized sprayer