The development of a model for the prediction of the risk appearance of downy mildew on Artichoke ( Bremia lactucae) was based on a biological model close to the Guntz and Divoux's one established on potatoes. The model uses simple meteorological data (relative humidity of air, hourly temperatures and rainfalls) and includes user's data (treatments, irrigation, stage of the crop and variety). The first year of the model fittings showed a good visualization of the real epidemic. Laboratory tests refine our knowledge about the life cycle and, associated to field observations, will allow to quantify more precisely the models parameters.
