The effects of the climatic changes more and more frequently, favour the emergence and the development of plant diseases. Botrytis cinerea and Oidium spp. spores are often responsible for enormous productivity losses in cultures with high commercial interests such as the grapevine. This work aims to detect these airborne spores, before the emergence of lesions in Vitis vinifera. In the rural area of Amares, the seasonal distribution of the concentration of the 2 spore types, was continuously studied between 1 March-31 October (2005-2007), using a 7-day volumetric Hirst-type spore trap. These data was compared with phytopathological data. B. cinerea sporulation occurs in March-April while Oidium spp. occurs in April-May. Fluctuations were observed due to the influence of different meteorological factors. The emergence of the first signs of grey mould and powdery mildew were preceded by increments of B. cinerea and Oidium spp. spore concentration. The precocious detection of increasing trends in airborne spore concentration of B. cinerea and Oidium spp. can notify the probable onset of grey mould and powdery mildew leading to application of lower quantities of phytopharmaceutical products in the most favourable developmental stage.