The most common problems when isolating fungi are contamination by
bacteria and yeasts, and the fact that the wrong species may inadvertently be
isolated. To overcome these problems, dilution of spore masses can be used to reduce the chances of yeast contamination and different antibiotics (e.g.
penicillin, 0.5 g/L, streptomycin, 0.5 g/L) can be used to reduce bacterial
contamination. There are several methods to ensure that the correct single spore
is isolated (Hansen, 1926) and a commonly used method is reported here.
Unfortunately, not all spores will germinate in artificial media, and other
techniques may be required for successful isolation of these fungi. Fungal
cultures stored in a high nutrient medium, such as Potato Dextrose Agar (PDA)
may lose their ability to produce enzymes or metabolites, or perform other
functions. Care is therefore needed in selecting a storage medium (Smith and
Onions, 1994).