Optimisation of a Vertical Spray Boom for Greenhouse Spray Applications

Proper delivery of pesticides into desired positions within crop canopies could result in a safe use of pesticides and reduce environmental pollution. A quantitative method with mineral chelates was used to evaluate spray deposits and distributions within tomato and pepper canopies. Tests were conducted in greenhouses with two different spray systems both equipped with vertical spray booms: a Fumimatic motor-driven sprayer and a manual-driven trolley sprayer. Deposition tests with water-sensitive paper and mainly with the manganese and molybdenum chelates as tracer elements were performed. Filter papers were placed at several heights within canopies to determine the spray distribution for changes in the vertical nozzle distance (0·35 versus 0·50 m) and the spray distance to the crop. The tests demonstrated that the spray with 0·35 m nozzle spacing provided a much better spray distribution than that with 0·50 m nozzle spacing. The optimal spray distance for 80° flat fan nozzles with the 0·35 m nozzle spacing was about 0·30 m.