Variation in fungal spore concentrations of selected taxa associated to weather conditions in Cracow, Poland, in 1997

The aim of the study was to determine seasonal variation in concentrations of selected fungal spore types due to meteorological parameters. The presence of spores of thirteen taxa: Cladosporium, Torula, Alternaria, Botrytis, Epicoccum, Stemphylium, Ganoderma, Erysiphales, Entomophthora, Drechslera type, Didymella, Polythrincium and Pithomyces was recorded in Cracow using a Burkard trap. The majority of selected taxa belong to the anamorphic fungi group, the others to Ascomycetes, Basidiomycetes and Zygomycetes. Fungal spores were present in the air in large numbers throughout the summer with the highest levels being reached in June, July and August although their highest concentrations differed with time. For most of the studied spore types: Botrytis, Ganoderma, Alternaria, Epicoccum, Torula, Drechslera type, Polythrincium, Stemphylium and Pithomyces the peak period was recorded in August. Didymella and Entomophthora spores reached their highest concentrations in July while concentrations of Erysiphales and Cladosporium spores were highest in June. Multiple regression analysis was performed for two seasonal periods: pre-peak and post-peak. In the pre-peak period concentrations of 10 spore types: Cladosporium, Botrytis, Epicoccum, Stemphylium, Drechslera type, Pithomyces, Didymella, Erysiphales, Ganoderma and Entomophthora were strongest influenced by minimum temperature while Alternaria, Polythrincium and Torula by maximum temperature (significance level of alpha = 0.05). During the post-peak period the most important factor affecting variation in concentrations of Botrytis, Polythrincium, Didymella, Erysiphales, Ganoderma and Entomophthora spores was the minimum temperature. For Alternaria, Cladosporium, Epicoccum and Torula the maximum temperature appeared to be the most influential, whereas for Drechslera type, Stemphylium and Pithomyces it was sunshine. All correlations between spore concentration, minimum and maximum temperature and sunshine were significant (significance level of alpha = 0.05), and positive although the percentage of explained variation (R-2) was low.