Spectrum of spray droplets with different nozzles and adjuvants

Abstract

Successful application of agrochemicals depends on factors such as the droplet size, nozzle type and solution composition. In this context, the objective of this study was to evaluate the spectrum of spray droplets with different spray nozzles by means of direct measurement. The experiment was conducted in a completely randomized design, with a factorial scheme 2 × 4 × 2 + 2 (nozzles x adjuvants x concentrations + controls), with four replicates. Used nozzles were the CVI 11002 and TVI 800075, the adjuvants were the Break-Thru®, Haiten®, Iharaguen-S® and Orix® additives added to the solution at the concentrations of 100 and 150%, and the control, without adjuvant. A particulate analyzer was used to obtain the droplet spectrum. The diameter of the volumetric median, diameter of the numerical median, relative amplitude and percentage of the volume of droplets smaller than 100 μm. The spray nozzle CVI 11002 presented the diameter of the favorable volumetric median for the solutions application and safety against drift and a more homogeneous droplet spectrum. The Break-Thru® adjuvant had lower risk of drift, and the increased concentration of Orix® adjuvant increased the homogeneity of the droplet spectrum.