Abstract

A field experiment was conducted to study the estimation of spraying losses on eggplant plants grown inside a plastic house belonging to the Agricultural Research and Experiments Station at the College of Agriculture - University of Basra, Karma Ali site, during the fall season 2022. An agricultural sprinkler with a full conical nozzle 8003 was used in spraying by placing white leaves on the plants to obtain Accurate details about the deposited spray droplets were obtained after photographing and analyzing them using ImageJ software. The study included four levels of pressure, 2, 3, 4, and 5 bar, three spray heights of 25, 50, and 75 cm, and three dimensions from the sides of the plant of 20, 40, and 60 cm. Some key indicators in sprayer performance for droplets falling outside the plant were evaluated, including volumetric average diameter (VMD), fine droplet diameters, spray coverage, deposition, and density. The experiment was carried out using factorial experiments (R.C.B.D.) with three replications and the least significant difference (L.S.D) with a probability level of 0.05. The results showed that spray drops were affected by all factors. The results also showed that there were significant differences between the studied characteristics when using the highest pressure, the highest height, and the farthest distance, as it gave the smallest average volumetric diameter and the highest ratio of diameters to fine droplets, with the highest percentage of coverage, sedimentation, and density of the droplets. While the lower pressure, lower height, and distance closest to the nozzle gave the largest average volumetric diameter and largest diameters of the fine droplets with the least number of drops and the lowest percentages of coverage, sedimentation, and density, with a decrease in the diameter of the fine droplets DV0.1. The results also showed that increasing both pressure and spray height led to a significant increase in the width and angle of spraying, volumetric loss when spraying, and increased waste in applying pesticides. The study recommends using a pressure of 2 bar and a spray height of 25 cm, as they contributed to reducing losses, increasing the percentage of spray solution, and achieving the maximum economic feasibility of spraying.