Influence of liquid-volume and airflow rates on spray application quality and homogeneity in super-intensive olive tree canopies.
Olive is a key crop in Europe, especially in countries around the Mediterranean Basin. Optimising the parameters of a spray is essential for sustainable pesticide use, especially in high-input systems, such as the super-intensive hedgerow system. Parameters may be optimised by adjusting the applied volume and airflow rate of sprays, in addition to the liquid to air proportion and the relationship between air velocity and airflow rate. Two spray experiments using a commercial airblast sprayer were conducted in a super-intensive orchard to study how varying the liquid volume rate (testing volumes of 182, 619, and 1603 l ha(-1)) and volumetric airflow rate (with flow rates of 11.93, 8.90, and 6.15 m(3) s(-1)) influences the coverage parameters and the amount and distribution of deposits in different zones of the canopy.. Our results showed that an increase in the application volume raised the mean deposit and percentage coverage, but decreased the application efficiency, spray penetration, and deposit homogeneity. Furthermore, we found that the volumetric airflow rate had a lower influence on the studied parameters than the liquid volume; however, an increase in the airflow rate improved the application efficiency and homogeneity to a certain threshold, after which the spray quality decreased. This decrease was observed in the high-flow treatment. Our results demonstrate that intermediate liquid volume rates and volumetric airflow rates are required for the optimal spraying of pesticides on super-intensive olive crops, and would reduce current pollution levels.
Department of Rural Engineering, University of Córdoba, Ctra. Nacional IV, km 396, Campus de Rabanales, Córdoba 14005, Spain.
Antonio
A
Miranda-Fuentes
Department of Aerospace Engineering and Fluid Mechanics, Universidad de Sevilla, Ctra. de Utrera km 1, Sevilla 41013, Spain.
Antonio
A
Rodríguez-Lizana
Department of Agri Food Engineering and Biotechnology, Universitat Politècnica de Catalunya, EsteveTerradas 8, Campus del Baix Llobregat D4, 08860 Castelledfels, Barcelona, Spain. Electronic address: emilio.gil@upc.edu.
Emilio
E
Gil
Department of Rural Engineering, University of Córdoba, Ctra. Nacional IV, km 396, Campus de Rabanales, Córdoba 14005, Spain.
J
J
Agüera-Vega
Department of Rural Engineering, University of Córdoba, Ctra. Nacional IV, km 396, Campus de Rabanales, Córdoba 14005, Spain.
Jesús A
JA
Gil-Ribes
D000383:Agriculture / Q000379:methods; D000393:Air Pollutants / Q000032:analysis*; D018556:Crops, Agricultural; D005060:Europe; D007300:Insect Control / Q000379:methods*; D031658:Olea; D010575:Pesticides / Q000032:analysis*
D000393:Air Pollutants; D010575:Pesticides
Airblast sprayer; Application efficiency; Application homogeneity; Spray coverage; Spray deposition