This paper presents results of research on the actions occurring in plant protection treatments that can affect the quality of treatments. These actions include: – storage of plant protection products – the choice of the operating parameters of the sprayer, – preparation of working liquid – a process execution spray – proceeding with the remainder of the liquid solution or pesticide residues. Attention was drawn to precision of execution actions and determined the overall suitability index (Cp), which defines the process of treatment plant protection products as unsuitable for the presently accepted quality requirements and construction currently used agricultural nozzle.

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