Edible Mushrooms

Abstract

Fungi are broadly identified by their sexual stage characteristics into four main classes: Ascomycetes, Basidiomycetes, Phycomycetes, and Fungi Imperfecti. Mushrooms are filamentous fungi grouped with the Ascomycetes and Basidiomycetes. A major difference in these classes is that the sexual spores of Ascomycetes develop in an asci sack and are released when the asci wall breaks down. Basidiomycetes produce a different structure, the basidium, in which sexual spores are formed and dispersed. Lacking chlorophyll, mushrooms do not carry out photosynthesis and therefore rely on other energy sources. Some are parasitic, others saprophytic, and some live in symbiosis with other plants. The majority develop the fruiting bodies epigeously (aboveground). For others, the fruiting bodies are formed hypogeously (below ground). Saprophytic species obtain their nourishment from nonliving organic matter. In general, these fungi produce fruiting bodies (ascocarps and basidocarps) called mushrooms when specific conditions of temperature, humidity, and nutrition are satisfied.