Towards more target oriented crop protection

Matching spray volume to crop canopy sizes and shapes can reduce chemical application, thus reducing operational costs and environmental pollution. Developments on crop adapted spraying are highlighted in orchard and arable crop spraying. A tree-specific variable volume precision orchard sprayer, guided by foliage shape and volume (canopy density sprayer; CDS) was developed. Spray deposition and biological efficacy and spray drift were evaluated in an orchard situation reducing spray drift by 25-90% and spray volume by 20-36% depending on growth situation. The transition of the potential of crop adapted spraying towards bed-grown arable crops is assessed. Sensor selection to quantify crop canopy is highlighted. Spray techniques to apply variable dose rates are evaluated. Potential volume rate savings are evaluated based on crop canopy structure evaluations during the growing season of bed-grown flower bulbs. It was shown that on average spray volume could be reduced by 25% and at early crop development stage even by more than 90%. Spray volume savings of a prototype plant-specific sprayer are shown to be more than 75% in early late blight spraying in potatoes.