THE CARBON AND NITROGEN NUTRITION OF CERTAIN FUNGI

Abstract

Carbon nutrition of Chaetomium sp., Myrothecium verrucaria, Pestalotia gracilis, and Pleurotus ostreatus was studied. Nitrogen nutrition was also examined with Nigrospora oryzae included. The effect of C/N ratio on fruiting was measured for the first four fungi. Several carbon sources including alcohols, carbohydrates, and organic acids were tested; in general, dextrin and L-arabinose were the most favorable for growth, starch was less so, whereas sodium acetate and sodium citrate were the least favorable. Maltose supported good sporulation of M. verrucaria, P. gracilis, and P. ostreatus. Organic nitrogen was superior to inorganic nitrogen for growth of M. verrucaria, N. oryzae, and P. ostreatus. The opposite was noticed for Chaetomium sp. and P. gracilis. Not all could grow on sodium nitrite at the concentration used nor sporulate on DL-methionine or ammonium sulfate. The best sporulation of P. gracilis was obtained with the maximum glucose and nitrate concentrations used (4% and 1% respectively), whereas the minimum concentrations (0.1 and 0.05% respectively) were best for the sporulation of P. ostreatus. Chaetomium sp. and M. verrucaria fruited best on intermediate concentrations of glucose and nitrate.