The impact of technical spraying factors on leaf area coverage with axial fan sprayer in apple orchard

Istraživanja su obavljena s aksijalnim raspršivačem (Hardi Zaturn) u nasadu jabuke. Cilj istraživanja je utvrditi utjecaj glavnih tehničkih čimbenika (tip mlaznice, brzina rada i norma raspršivanja) na pokrivenost tretirane površine, broj kapljica cm2, prosječni promjer kapljica i zanošenje tekućine. Brzina rada raspršivača podešava se na 6 i 8 km/h, a norma raspršivanja na 250, 325 i 400 l/ha. U istraživanju su se koristile plave (TR 8003), žute (TR 8002) i zelene (TR 80015) Lechler mlaznice. Istraživanje se postavlja kao trofaktorijalni poljski pokus sa 18 tretmana u 2 ponavljanja. Pri svakom tretmanu na stablo je postavljeno 60 vodoosjetljivih papirića koji su obrađeni računalnom analizom slike i računalnog programa ImageJ. Uz glavna svojstva istraživanja otvrđuju se indeks lisne površine (LAI) i indeks lisne gustoće (LAD) te brzina i protok zračne struje. Prije samog istraživanja utvrđeno je da raspršivač zadovoljava standard EN 13790. Smanjivanje ISO broja mlaznice, povećanjem norme raspršivanja te povećanjem brzine rada povećava se pokrivenost tretirane površine, broj kapljica/cm2 kao i zanošenje tekućine (drift) dok se prosječni promjer kapljica smanjuje. Postignuti rezultati aksijalnog raspršivača (Hardi Zatrun) u nasadu jabuke : pokrivenost tretirane površine kreće se od 26,03 do 54,40%, ostvarena vrijednost broja kapljica/cm2 kreće se od 51,83 do 155,67 kapljica, prosječni promjer kapljica kreće se od 131,15 μm do 204,41, vrijednosti ostvarenog zanošenja tekućine kreću se od 10,12% do 40,41%.Researsches are conducted with axial mistblower (Hardi Zaturn) in apple orchard. The aim of the research was to determine the influence of the major technical factors (type of nozzle, working speed and spraying volume) on coverage of the treated area, average droplet diameter, number of droplets per cm2 and drift. The operation speed was set at 6 km/h and 8 km/h, spray volume was set on 250, 325 and 400 l/ha. Nozzles which were used in this research are : blue (TR 8003), yellow (TR 8002) and green (TR 80015) Lechler nozzles. The research was set as three – factorial field experiment with 18 treatments in 2 repetitions. For each treatment the tree was covered with 60 water sensitive papers which were later processed with digital image analysis and ImageJ software. In addition to the main features of research, researches determined leaf area index (LAI), lead area density (LAD), speed and flow of air current. Before research, researches determined that mistblower meets the EN 13790 standard. By decreasing the ISO number of nozzles and by increasing the working speed and spray volume, we found increasement of area coverage, number of droplets per cm2 and drift, and decreasement of average droplet diameter. The results obtained with axial mistblower (Hardi Zaturn) in apple orchard are : coverage of the treated area ranges from 26,03 to 54,40%, number of drops/cm2 ranges from 51,83 to 155,57 drops, average diameter of droplets ranges from 131,15 to 204,41 μm, the value of realized drift ranges from 10,12% to 40,41%