Biodiversity of soil-inhabiting fungi

This survey is concerned only with filamentous fungi living in the soil layer. The observed diversity of soil fungi largely depends on the method used and the numbers of isolates obtained. Particle-plating usually yields higher numbers of taxa than dilution plating. The Centraalbureau voor Schimmelcultures (CBS) preserves a great diversity of soil fungi. The CBS database contained 2,210 species of soil fungi in 2001, an estimated 70% of the known species available in culture. Thus, the current estimate for described culturable soil fungi is approximately 3,150 species, many of which have a cosmopolitan distribution. Adding the ca. 150 spp. of nonculturable Glomerales results in 3,300 species of currently known soil fungi. Molecular studies in such groups as Fusarium, Trichoderma, Penicillium, and Aspergillus are finding a number of more narrowly distributed cryptic species. Thus the number of species of soil fungi is expected to be considerably higher than the 3300 species currently known.