[Opportunistic fungi in the atmosphere].

Our knowledge in aerobiology has considerably increased in the last 20 years due to new trapping methods. The use of volumetric spore traps permits to accurately analyze the particles suspended in the air and their evolution, while the deposition method gives an incomplete picture of the real air content. The air microflora changes considerably during 24 h: some groups of spores occur in the morning, others in the afternoon and yeast-like organisms during the night. The most common fungi in the atmosphere are Cladosporium sp., Sporodbolomyces considerably increase (20-10(3) times) the number of spores released in the atmosphere. Aspergillus flavus, thermophilic actinomycetes, Botrytis cinera and Didymella exitialis are cited as examples.