The "Polo Turístico do Circuito das Frutas"� region congregates counties that produce "Niagara Rosada"� grapevine. The grapevines suffer severe influence of fungal diseases and their control reach up to 30% of the production cost. Aiming to determine the climatic risk (CR) for 'Niagara Rosada' grapevine fungal diseases occurrence, a rainfall data bank was used to estimate the necessary number of sprays to control the main fungal diseases. The CR, as well as the necessary number of sprays, was calculated for the different probable harvest dates, for each pruning date at the different counties. The characterization of the different growing areas considering the higher need of fungicide sprays to control fungal diseases as a function of rainfall occurrence was done by means of GIS, using estimated values of CR through regression equation based on altitude. The September pruning dates presented higher CR values than July, being the highest values over 70% and the lowest under 20%, respectively.
viticulture; rainfall; harvesting date; phytosanitary control
