Fifty genera and 155 species, in addition to three varieties of Aspergillus nidulans, were isolated from 100 soil samples collected from different localities in Egypt. Aspergillus (33 species in addition to 3 varieties of A. nidulans), Penicillium (46 species), Fusarium (6 species) and Mucor (4 species) were of high occurrence, from which A. niger, A. fumigatus, A. terreus, M. racemosus, P. notatum, P. chrysogenum and A. flavus were dominant. Five genera were of moderate occurrence and these were Humicola, Myrothecium, Rhizopus, Cochliobolus and Alternaria. Fourteen genera were of low occurrence namely, Cunninghamella, Chaetomium, Stachybotrys, Cladosporium, Syncephalastrum, Paecilomyces, Trichoderma, Scolecobasidium, Circinella, Curvularia, Ulocladium, Botryotrichum, Sepedonium and Gliocladium. Twenty-seven genera were of rare occurrence.
Fourteen species were of moderate occurrence and these were A. sydowii, M. verrucaria, P. funiculosum, A. versicolor, H. grisea, F. oxysporum, A. nidulans, F. moniliforme, A. alternata, F. solani, M. hiemalis, A. candidus, R. nigricans and A. ochraceus. The remaining species were of low or rare occurrence in soils tested.
Comparison between the present results and those of others showed that there is no fungal flora characteristic cultivated soils.