Evaluation of Electrostatic Spraying Equipment in a Greenhouse Pepper Crop

Abstract

Greenhouse vegetable production is of great importance in southern Europe. It is a cultivation system characterised by a high planting density and environmental conditions that favour the development of pests and diseases. Although alternatives to chemical pest and disease control have been used over recent years in greenhouse crops, it is still mostly plant protection products that are used to protect crops and prevent crop losses. Hand-held spraying equipment is mainly used to apply plant protection products to this type of crop. This equipment is technologically basic, offering low deposition efficiency in the plant canopy, high losses to the ground, and a high risk of worker exposure. In this context, it is important to utilise technologies that reduce the problems associated with using the conventional hand-held sprayers in greenhouses. This study evaluated the deposition and uniformity in the plant canopy and the losses to the ground when applying plant protection products with an electrostatic hand-held sprayer; the results were then compared with applications carried out using a conventional hand-held sprayer. For this purpose, a colorimetric method has been used based on the application of a tartrazine solution. The tests showed that the electrostatic spraying equipment increased the plant canopy deposition by 1.48 times that of the hand-held spray gun, resulting in a 48% reduction in the application rate. There was also a 1.78-times increase in deposition on the underside of the leaves and a 36.36% reduction in losses to the ground. In general, the electrostatic hand-held sprayer improves the effectiveness of the plant canopy deposition and reduces losses to the ground compared to the hand-held spray gun commonly used in pest and disease control.