IMPACT OF TEHNICAL SPRAYING FACTORS ON LEAF AREA COVERAGE IN PERMANENT CROPS

Istraživanja su obavljena u vinogradu i nasadu jabuke sa dva tipa raspršivača, aksijalni (Hardi Zaturn) i radijalni (Hardi Arrow). Istraživan je utjecaj glavnih tehničkih čimbenika raspršivanja (tip mlaznice, brzina rada i norma raspršivanja) na pokrivenost tretirane površine, prosječni promjer kapljica, broja kapljica/cm2 i zanošenje tekućine. Brzina rada raspršivača podešava se na 6 i 8 km/h, a norma raspršivanja na 250, 325 i 400 l/ha za nasad jabuke te 250, 300 i 350 l/ha za vinograd. Koriste se plave (TR 8003), žute (TR 8002) i zelene (TR 80015) Lechler mlaznice. Istraživanje se postavlja kao trofaktorijalni poljski pokus sa 18 tretmana u 4 ponavljanja, kako za tip raspršivača tako i za vrstu nasada. Po tretmanu na stablo/trs postavljeno je 60 vodoosjetljivih papirića koji su obrađeni pomoću računalne analize slike i računalnog programa ImageJ. Uz glavna svojstva istraživanja utvrđuje se indeks lisne površine i gustoće, brzina i protok zračne struje, radni tlak, usmjerenje mlaznica te se prate vremenski uvjeti tijekom istraživanja. Prije samog istraživanja, raspršivači se testiraju prema europskom standardu EN 13790. Smanjivanjem ISO broja mlaznice, povećanjem brzine rada raspršivača te povećanjem norme raspršivanja povećava se pokrivenost tretirane površine, broj kapljica/cm2 i zanošenje tekućine, a smanjuje se prosječni promjer kapljica. Usporedbom dobivenih rezultata istraživanja eksploatacijom aksijalnog i radijalnog raspršivača u vinogradu i nasadu jabuke, bolje rezultate postiže radijalni raspršivač (Hardi Arrow) u oba slučaja. Najbolji odnos pokrivenosti tretirane površine i zanošenja tekućine u vinogradu ostvaruje se sa pokrivenošću tretirane površine od 64,22% i zanošenja tekućine od 17,11% (zelena mlaznica, brzina rada od 6 km/h, norma raspršivanja od 350 l/ha te radni tlak od 10,99 bar). U nasadu jabuke navedeni odnos ostvaruje se sa pokrivenošću tretirane površine od 59,55% i zanošenja tekućine od 21,10% (zelena mlaznica, brzina rada od 8 km/h, norma raspršivanja od 325 l/ha te radni tlak od 16,84 bar).Researches are conducted in vineyard and apple orchard with two different types of mist blowers, axial (Hardi Zaturn) and radial (Hardi Arrow). The influence of major technical spraying factors (type of nozzle, working speed and spray volume) were observed on coverage of the treated area, average droplet diameter, number of droplets per cm2 and drift. The working speed of sprayer was set at 6 and 8 km/h, and spray volume on 250, 325 and 400 l/ha for apple orchard and 250, 300 and 350 l/ha for vineyard. Researchers used Lechler blue (TR 8003), yellow (TR 8002) and green (TR 80015) nozzles. The research was set as three - factorial field experiment with 18 treatments in 4 repetitions, for different type of sprayer and permanent crops. We used 60 water sensitive papers for that treatment, which were processed with digital image analysis and ImageJ software. In addition to the main features of the research, research showed leaf area index and density, speed and flow of air current, working pressure, orientation of the nozzles and weather conditions, which were monitored during the study. Before the research, mist blowers are tested according to the European standard 13790. 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 cm2and drift, and decreasement of average droplet diameter. Also, by comparing the results of research exploitation by axial and radial mist blower in the vineyards and apple orchards, better results are achieved with radial mist blower (Hardi Arrow) in both cases. The best relationship of area coverage and liquid drift in vineyard were achieved with 64,22% area coverage and 17,11% of liquid drift (green nozzle, working speed of 6 km/h, spray volume of 350 l/ha, and working pressure of 10,99 bar). In apple orchard the best relationship of area coverage and liquid drift were achieved with 59,55% area coverage and 21,10% of liquid drift (green nozzle, working speed of 8 km/h, spray volume of 325 l/ha, and working pressure of 16,84 bar)