For the Flemish leek growers is particularly difficult to combat blight paper. If leek growers attempt to control the disease at the appearance of the paper stains treatments largely too late. Indeed, there is a long period between the infection by the oomycete Phytophthora porri and the development of the symptoms. Another strategy for the grower is to protect the crop continuously by regular preventive treat. In both cases, the economic cost of walking on what the profit margin for the leek grower fall knowing that the average prices have not risen more since the early '90s. This project aims to remedy this by alerting growers at a real risk of infection. Because this probability is very plot-related, the partners in this project will develop a web application. Giving leek growers the ability to insert plot related information. Based on this input, the grower may be advised very specific. The web application itself uses an advisory model that was developed in the IWT Project 040 728. The main factors that should be taken are known for an optimal and efficient control of paper blight. First, there is the field of meteorology demonstrated a strong link between the spread of the disease and the amount of rainfall. Second, soils contain different amounts of oospores which to a large extent determine the infection pressure. The third observation is that there is a large spread in the natural resistance of the leek cultivars. As a final point, the control scheme also plays a crucial role. The period of persistence and the previous use of plant protection controls significantly the development of Phytophthora porri. Further research is needed to develop the web application. The project is structured around four pillars. Two pillars ensure the application of new information about the primary inoculum and require a scientific approach. The other two are built around the development of a web application and further validation of the opinion that the model ingectiekans is calculated. These pillars require a technical approach and are very practical. The main objective of the Project is clearly oriented towards the practice. It is the Flemish leek growers will have after the PRoject a practical tool to combat blight paper in a sustainable and integrated manner.