Optimization of copper treatments in organic viticulture by using a web-based decision support system

This paper presents Coptimizer, a model-driven decision support system designed to help growers to optimize and track the use of copper-based fungicides against grapevine downy mildew in European organic viticulture, where the use of only a fixed amount of copper per year per hectare is permitted.Copper is a preventive fungicide allowed in organic agriculture that is active only at the application site (i.e. it is non-systemic), so that new plant growth results in unprotected tissues. In areas where disease incidence is high, organic farmers usually apply weekly copper treatments at the risk of exceeding the fixed threshold. The capability of Coptimizer for not exceeding the copper threshold was evaluated in simulation using historical data and tested in two experiments under field conditions during 2008. The results show that by using Coptimizer growers could be able to maintain the same level of protection as that gained by traditional application schedule while applying only half the amount of the fungicide.