Evaluation of Spray Droplets Characteristics Depending on the Configuration of Boomless Nozzle

Abstract

Using hollow cone nozzles is a common in different spraying processes for controlling the pests. The aim of the study was to evaluate the spray droplet characteristics deposited on the eggplant plants at flowering vegetative growth stage. The study was performed in a Complete Block Random Design (CBRD) with a 3x4 factorial scheme, consisting of three working pressures 2, 3, and 5 bar, and four spray patterns of nozzles with three blocks. For obtaining micro details about spray droplets characteristics, white paper cards were used, which later had their images digitized and analyzed by the ImageJ software. The following values were measured in this study: volume median droplet diameter, spray coverage percentage, and droplet density per centimeter square. Then, the values found were subjected to analysis to show the significance between them. These values were compared by t test at 5% probability level. For each factor, separately, the coefficients of variation were analyzed and then the correlation between these factors was performed. The main results showed that the spray droplet characteristics were affected by both of operating pressure and spray pattern configuration. Higher operating pressure of 5bar produced the smallest median diameter and greatest number of droplets, and spray coverage percentage. Results also showed that the using of a combination spray pattern led to an increase in droplet density thereby coverage percentage into plant canopy in comparison to other pattern configurations.