ABSTRACT
Farmers are seeking pesticide treatments with lower application rates and higher travel speeds. However, this can lead to a poor quality of the application. The aim of this study was to evaluate the spray deposition on soybean crop and the droplet spectra using different application rates and speeds. The experiment was conducted in soybean (R5 stage), M 6410 IPRO variety. Six treatments involving two application rates (80 and 150 L ha-1) and three speeds (10, 15 and 20 km h-1) were evaluated through a self-propelled sprayer. A characterization study of the spray droplets was conducted through the evaluation of water sensitive papers. The spray deposition study was carried out. For this, a marker was added to the application to be detected by absorbance in spectrophotometry. The use of spray nozzles with higher nominal flow, as well as lower pressures, produced droplets of larger sizes. The application rate of 80 L ha-1 provided equal and higher spray retention in the lower and upper leaves of the plants, respectively. The three speeds did not influence the deposition on soybean plants.
KEYWORDS
application technology; Glycine max; sprayer
