Mushroom is also known as agaricus campestris. It is of edible type. It is Saprotrophic and occurs in moist soils, grasslands etc. Mycelium multiplies by fragmentation. Basically, two types of mycelia are formed in life cycle of mushroom. They are primary and secondary respectively. Primary mycelia are short lived with single nucleus cells known as monokaroytic cells. The mycelia are heterothallic type. While secondary mycelia are long lived and have Dikaryotic cells. These cells have two haploid nuclei and show clamp connections. Occasionally when the conditions are favorable the hyphae of secondary mycelium give rise to mass of hyphae known as buttons. The buttons may show fruit formation referred as basidiocarps. These are also known as mushrooms. Spawn is defined as the secondary mycelium from which mushroom develops. Mushroom often occur in rings known as fairy rings. Mushroom is divided into stipe and pileus. The stipe is fleshy while pileus forms the umbrella portion of mushroom. These both parts are connected to each other by velum. As pileus grows these velum ruptures and their remains are known as annulus. The under surface of pileus is flat and concave with row of vertical plates referred as gills. Gills are vertically placed and are covered by multiple club shaped basidia. It is also accompanied by paraphyses. They both make hymenium of the gill. The centre of hymenium consists of interwoven hyphae called trama. Karyogamy and meiosis occurs in basidia. The two nuclei give rise to four haploid nuclei. A peg like structure is formed at the free end of basidia called as sterigmata and they form an ovoid pink purple spore known as basidiospore.
The different species of basidiomycetes includes rusts, smuts, mushrooms, toad stools, bracket fungi and puff balls.
Rusts have no basidiocarp they have rusty pustules with spores. They may lead to black and yellow rust of wheat. Smuts have thick walled resting spores known as smut spores. They may be loose or covered. In loose types the smut spores are uncovered and attached to the host cells. While in covered type they are confined to host. Mushrooms can be edible or non edible. They have umbrella like structure. They belong to agaricus group. Toad stools are poisonous, non edible mushrooms. They produce white spores. Caesars mushroom is the most common mushroom which was used to poison Emperor Caesar. Bracket fungi are also known as shelf fungi. They mainly occur on tree trunks, logs and lumber etc. Puff balls make puffs of spores and have stalk like shape. They are edible. Hallucinogens are quite similar to LSD. They are mainly used by Mexican Indians.
