Fruiting of A. bisporus depends on a complex set of variables
including atmospheric factors such as carbon dioxide concentration,
temperature, humidity and pH and on the
nutritional status of the substrate (Flegg & Wood, 1985). To
induce synchronous fruiting during commercial cultivation of
A. bisporus, the full-grown compost is covered by a (nonsterile)
casing layer consisting of peat and lime. After
colonization of the casing layer, fruiting is stimulated by
lowering the ambient temperature and carbon dioxide
concentration in the growing rooms