Today, there are more than 100,000 types of mushrooms in the world. They differ in appearance, habitat and physiological functions.
To this most interesting group belong the little known microscopic mushrooms and the common forest mushrooms – which are the target of a «quiet hunt». They are all alike in their structural features, which are characteristic to almost all types. Mushrooms don’t contain chlorophyll, hence they are unable synthesize organic substances from the inorganic matter on their own; therefore they need a ready organic substance for their nutrition (it’s called heterotrophic). The basis of a mushroom’s vegetative body is mycelium or spawn which is composed of branching fibers – the hyphae. The mycelium is on the surface of the substrate, where the mushroom develops, or inside it. The mycelium absorbs nutrients from the substrate in an osmotic way. When the conditions are favorable, fruit bodies form on the mycelium, and the mushrooms propagate with spores.
People’s aspiration for learning about these wonderful organisms has led to the formation of a whole new science – mycology. Mycology is a science that studies mushrooms, it got its name from a Greek word «mycos» - that’s how ancient Greeks called agaricus. Agaricus and some other mushrooms were mentioned in the transactions of Theophrastus who lived in the 3rd century B.C.
According to the systematization of all known mushrooms – agaricus belongs to Basidiomycetes species, the higher fungi with multi-cellular mycelium. The spores of these mushrooms form on particular offshoots called basidium.
Due to the fleshy fruit body with a central stipe and a cap on it and the lamellar hymenophore, agaricus was classified as the Agaricales.
The Agaricaceae genus consists of 13 species of mushrooms of various kinds. The mushrooms of this genus have loose laminae and there’s a ring on the stipe left from the veil.
The genus Agaricus consists of more than 60 kinds of mushrooms. The name Agaricus was given to this kind of mushroom by the international botanist congresses in Stockholm in 1950, then in Paris in 1954.
Mushrooms that belong to this genus mostly belong to saprophytic mushrooms and grow in dunged ground, manure and on forest humus rich in organic substances. Many kinds of Agaricus mushrooms are spread all over the world. They can be found in the steppe and forest-steppe zones of Europe, in the Central Asian steppes, in the North American prairies, in the South American pampas, in fields and open sites of Australia and Africa.
Agaricus mushrooms are divided into five ecological groups, depending on the substrate they grow in:
- Mushrooms that grow only in the forest;
- Mushrooms that grow in open areas, with no grass;
- Mushrooms that grow in open areas in grass;
- Mushrooms that grow in open areas in grass and in the forest;
- Desert types;
Out of all these various kinds of mushrooms only two are poisonous – Agaricus meleagris and Agaricus xanthoderma. The fruit bodies of other kinds of mushrooms are edible and are used for food in many regions of the world.
Out of the wide variety of mushrooms, the kind used for industrial cultivation is the Agaricus Bisporus. This mushroom became a true crop. It is cultivated in many countries of the world. An excellent taste, economy, and abundant fruiting are the basic qualities which became the reason for cultivating these mushrooms.
In the end of the 60s of the 20th century mushroom growers from some countries started cultivating another kind of mushroom – Agaricus bitorquis.