Agaricus macrosporus: An edible fungus with commercial potential

An investigation into the growth and nutrition of Agaricus macrosporus (Møll and Schäff) Pilát was performed to provide comparisons for studies with Agaricus bisporus (cultivated mushroom) and also as part of a programme to evaluate alternative Agaricus species for commercial use.A. macrosporus was grown on standard media; most rapid mycelial growth occurred at 24–27°C (maximum temperature for strong growth 30°C) on malt extract agar, although linear growth rates were lower than those of A. bisporus and A. bitorquis grown under similar conditions, and fruit-body primordia were rarely formed. Most rapid growth on agar occurred at pH 5–8, but little biomass was formed in shallow, pH-controlled liquid culture.A. macrosporus grew poorly on most individual carbon sources, with the exception of hexose monosaccharides. A. macrosporus grew well on complex nitrogen sources and amino acids, but ammonium nitrate was the only nitrate source to support any more than minimal growth. Rapid mycelial growth occurred in basal media containing 0.1–1 g l^?1 N (as arginine), corresponding to a C:N ratio in the media of between 5 and 35:1. A. macrosporus grew slowly, but fruited using the methods of commercial mushroom culture.