| Abstract: | Reduction in the amount of active substance and reduced dependence on chemical plant production products are the main items in the Dutch Government Multiyear Crop Protection Plan. There are problems in reaching this goal, as weather conditions in The Netherlands are very beneficial to all kinds of fungal diseases. Such diseases have to be controlled by applications of preventive fungicides, and it is quite regular to use a spray interval of 6–7 days. Another problem is application at the wrong time. With the help of decision‐support systems (DSSs), it is possible to calculate the period of protection by a product, the danger of an infection period and the moment of highest efficacy. DLV‐Meteo offers advice based on five DSSs for individual pests (Prophy, onion leaf spot disease, Botrypré, Mycos and Contapré) and on a general DSS for application at the time of day that ensures highest efficacy (Gewis). |
