Fungal flora associated with combine harvester wheat and sorghum dusts from Egypt

107 species and 8 species varieties belonging to 44 genera were collected from combine harvester wheat and sorghum dusts (35 genera and 91 species + 4 varieties) and from the atmosphere of their hay sites (26 genera and 69 species + 4 varieties) on glucose- and cellulose-Czapek's Dox agar at 28 degrees C and 45 degrees C. The mycoflora of wheat and sorghum dusts were basically similar on the two types of media and the most common fungi were: Alternaria alternata, Aspergillus flavus, A. fumigatus, A. niger, A. ochraceus, A. sydowii, A. terreus, Cochliobolus spicifer, Emericella nidulans, Fusarium moniliforme, Penicillium chrysogenum, P. duclauxii, P. funiculosum and P. oxalicum. Truly thermophilic species were frequently encountered from the two substrates: Chaetomium thermophilum, Humicola grisea var. thermoidae, H. insolens, Malbranchea pulchella var., sulphurea, Rhizomucor pusillus, Sporotrichum thermophilum, Talaromyces thermophilus, Thermoascus thermophilus and Thermomyces lanuginosus. The airborne fungi in the two atmospheres were basically similar and the most prevalent species were members of Alternaria (1 species), Aspergillus (18 species + 2 varieties), Chaetomium (2 species), Cochliobolus(3 species), Emericella (3 species + 2 varieties), Fusarium (3 species), Mucor (1 species), Penicillium (14 species) and Stachybotrys (1 species).