Substrate selection of some higher fungi in relation to their tolerances in aseptic cultures

Chemical factors play a major role in limiting the occurrence of fungi. Pure cultures of higher fungi belonging to several ecological groups were grown on 1% malt extract agar supplemented substances found in natural substrata, i.e., ethanol, tannin, nitrate, manganese sulfate, sulfuric and sulfurous acids, and nine organic acids. The maximum concentrations at which growth occurred were determined. Different species showed great differences in tolerance which, in general, correlated positively with the presence of those substances in the species' habitats. Certain fungi had exceptionally high tolerances especially to tannin, sulfuric acid and manganese sulfate.