The relationship between sporophore initiation in Agaricus bisporus and the function of the casing layer has been investigated. Initiation vies found to be controlled by crrbon dioxide and the activity of micro-organisms. No evidence was discovered for the involvement of other volatile factors. Vegetative growth into compost and casing showed an absolute requirement for CO2. Sporophore initiation end early development of carpophores also required exogenous CO2. Optimal CO2 levels for initiation lay between 340 and 1000 p.p.m. Above these CO2 concentrations vegetative growth was enhanced with a concommitant decline in the numbers of fruit bodies produced. Although no specific active micro-organisms could be isolated earlier reports of microbial involvement were confirmed. It was not possible to induce carpogenesis in sterile oasing materials other than gas adsorbent charcoal. It is suggested that microorganisms could function in initiation through irreplacable removal from hyphal apices of metabolites promoting vegetative growth. These substances may be synthesised from, the products of CO2 fixation, which could account for the suppression of carbogenesis by excess CO2.
|Date of Award||1968|