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Improving pesticide spraying techniques for tree crops - PA1721

Axial fan sprayers are commonly used for pesticide application to UK top fruit because they are convenient to operate in a wide range of orchards and are mechanically reliable. However, it is common practice to operate this equipment with air flow and spray distributions that are inappropriate for modern orchard structures which poses a high risk of environmental and operator contamination.

The purpose of this project is to produce soundly based practical rules for the adjustment of axial fan sprayers to suit a wide range of different UK orchard structures taking into account the need to optimise pesticide spray distribution. This information is vital to needs of the industry to comply with the Code of Practice for the Safe Use of Pesticides on Farm Holdings which places a duty on users to spray safely and effectively, but currently offers no guidance on how this should be done in different orchards. Moreover, pesticide labels in the UK currently recommend a fixed maximum dose rate and minimum volume rate for orchards, regardless of tree size and growth stage. These recommendations should be tested to determine both the efficiency of pesticide use as well as the implications for off-target contamination in a wide range of apple orchard structures and practical operating conditions.
1. Establish the models of the operational adjustment of an axial fan sprayer and improve the method of optimisation.
2. Establish performance characteristics for air injector nozzles to extend the range of operational adjustments included in the model.
3. Provide further performance characteristic measurements of operational adjustments to consolidate modelling activity.
4. Verify biological performance of reduced air volume flow adjustment and the use of air injection nozzles by field efficacy experiments.
5. Produce a technical leaflet for growers on the optimal adjustment of axial fan sprayers including an assessment of crop structure effects linked to growth stage.
Project Documents
• Final Report : Improving pesticide spraying techniques for tree crops   (4731k)
Time-Scale and Cost
From: 2000

To: 2001

Cost: £359,182
Contractor / Funded Organisations
Horticulture Research International, Silsoe Research Institute (BBSRC)
Pest and Weed Control              
Pesticide use              
Plants and Animals              
Fields of Study
Pesticide Safety