Modification of Pesticide Sprayer to Suit the Orchard Trees تعديل الة رش المبيدات لتناسب اشجار البساتين

Abstract

This study aims to develop a commonly used sprayer in the Egyptian farms (gun sprayer, Alcon Motori) adapted for orchard fields. The main aspect of the modified sprayer was the ability to move nozzles at vertical reciprocating motion NVRM which improves the deposition of the pesticide on upper and lower leaf surfaces. The modified sprayer included the following parts: nozzle carrier frame, pesticide tank, pump, pressure regulator, pressure gauge and hoses. The modified sprayer was evaluated under three different forward speeds "FS" of 2.4, 3.4, and 4.6 km/h, three nozzle reciprocating displacement "NRD" of 250, 400, and 600 mm, and three values of operating pressure "OP" of 1000, 1500, and 2000 kPa on the number of droplets deposition at the upper and lower leaf surface, the dropletmean diameter, application rate, machine field capacity, and spraying cost. Results revealed that increasing the forward speedcaused decreasing the number of droplet; droplet means diameter, application rate, spraying cost, and increasing the sprayer field capacity. The droplet density and droplet mean diameter were inversely proportional to the nozzle reciprocating displacement. The operatingpressure at 2000 kPa resulted in the highest droplet density and the lowest droplet mean diameter at different forward speeds and nozzles reciprocating displacement.