The MASTER-project: measures and state-of-the-art techniques for pesticide dust emission reduction during sowing

The use of seeds dressed with pesticides is widespread and has important advantages. The most important disadvantage of this technique is that there is a possible emission of pesticide laden dust particles during sowing. The main factors affecting the emission of pesticide-laden dust are seed treatment quality, the environmental conditions and the seed drill technology used (Nuyttens et al. 2013).
Due to the bee killing incidents observed in several European countries, the crop protection industry and the coating and seed technology companies have made important improvements with regard to seed treatment quality. In several countries, the use of air deflectors on sowing machines was made mandatory. In some cases, like in Belgium, air deflectors are only required with certain products. Furthermore there is some evidence that they are not always used in practice. In addition, there are still questions about the efficiency and the optimal machine settings, the drift reducing effect of deflectors, the effect of environmental and soil conditions, the relevance of dust drift and its impact, etc. Therefore, a 4 year research project ‘MASTER’ was started end of 2011. An overview and the status of the project will be presented at the workshop.
The MASTER-project aims at quantifying the risk of dust drift and developing dust drift reducing measures and innovations in sowing techniques using an integrated experimental and modelling approach. In a first step, the dust drift potential of several treated seed batches was assessed using the Heubach method and information about the chemical and physical characteristics of abraded pesticide-coated seed particles was gathered (Foqué et al. 2013). Then the air flow pattern and dust emission of two pneumatic sowing machines, a precision drill (Gaspardo Stella ST 300) and a bulk drill (Kuhn Venta nc 3000) at different settings, is measured under controlled conditions. Using this information, a CFD sowing machine model will be developed to simulate the dust behaviour in and around the machine in order to evaluate the effect of machine design and settings on dust emission (Devarrewaere et al. 2013). A CFD dust drift emission model will simulate the behaviour of dust in the environment. Dust drift field experiments will be done to evaluate the effect of machine, seed treatment quality and environmental conditions on dust drift and to validate the CFD dust drift emission model.