Influence of emulsifiable concentrate formulation on the physical properties of the fluid, spray characteristics, and insecticide deposits on stored grains.

In stored grains, smaller depositions and great variations with regard to theoretical insecticide doses are frequently found. The objective of this work was to evaluate the influence of the emulsifiable concentrate formulation on the physical properties of the liquid, volumetric distribution, droplet spectrum, and insecticide deposits on stored grains. To determine its physical properties, the applied mix was prepared at a concentration of 0.4% of commercial product. Volumetric distribution was used as an evaluation parameter in a model TJ-60 8002EVS hydraulic nozzle study, and clean water and insecticidal mix were used as test fluids. After the effective swath width (esw) had been determined for both fluids, an application system was built to apply theoretical concentrations of 10 and 0.5 mg kg-1 of fenitrothion and esfenvalerate, respectively. Mix viscosity was 82% higher than water viscosity; conversely, surface tension in the mix corresponded to 49% of the water surface tension value. For water and mix, esw values were 0.425 and 0.60 m, respectively. Deposits of both insecticides at the 0.60 m esw were significantly higher (P<0.05) than deposits at the 0.425 m esw. The results obtained demonstrate the great influence of emulsifiable concentrate formulation on the physical properties of the fluid, spray characteristics, and insecticide deposits on stored grains.