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Agaricus Introduction Somatic structure (Vegetative thallus) and Their Mode of Reproduction


The variety Agaricus contains a gathering of 200 animal groups which are heterotrophic, genuine nucleated, multicellular, perceptible and beefy in nature. This gathering incorporates parasites whose fruiting bodies are normally known as mushrooms. The umbrella molded mushrooms (which are palatable), toadstools (which are nonedible or harmful) embellish this world with their quality in practically all seasons aside from the outrageous summers and winters. 

The fruiting assortments of certain species show up in late-winter and vanish in summers, others show up just in blustery prepare and some show up irregularly at whatever point dampness is accessible. Subsequently the wet season (stormy climate) is the best season to investigate, notice and gather the most delightful, bright (hearty blossoms) fruiting collections of mushrooms in slopes just as in fields. 

The word mike's (from which the term Mycology is inferred) implies mushrooms and etymologically, mycology is the investigation of mushrooms. This gathering has been widely concentrated in detail since man gathered the fruiting assemblages of mushrooms from different territories to burn-through them as food, medications and so forth.

Propensity and Habitat 

Agarics is a multicellular, naturally visible, generally saprophytic corticolous, parasitic and mycorrhizal in nature. Agarics are cosmopolitan in nature and happen in a wide assortment of environments going from the cold to the jungles. The majority of the species do show the inclination to the assorted sort of foundations for instance :- 

In upland woody timberlands on rotting wood (lignicolous), rotting fallen leaves (foliaceous) eg. A . lanes, A. langei, on soggy soils (earthbound), fertilizer and waste (coprophyllous) eg . A. bisporus, A. bitorquis . 

Substantial Structure (Vegetative Thallus) 

The fruiting bodies (sporo phores) of mushrooms as seen on the outside of base by the unaided eye don't display the total parasitic thallus yet these are the sexual conceptive bodies bearing meiotic basidiospores with respect to mycelium . 

The physical structure or vegetative thallus of Agaricus comprises of the mycelium (mass of hyphae) which is septate, slight walled, hyaline ordinarily a basidiomycetous kind. Here it emerges as an essential mycelium from the mono karyotin basidiospores, which later become dikaryotic and tertiary mycelium. 

Essential mycelium :The monokaryotic, haploid, basidiospore of (+) and (- ) strain develops following dispersal on the base or on the wet soil (at 10-15 degree temperature, 80—90% relative stickiness, and 5.8—6.o ph.) by retaining mineral supplements straightforwardly in dissolvable structure to give rise a germline or essential hyphal beginning . This hyphal beginning cell goes through mitotic division to frame mono karyotin, uni nucleated, haploid, hyaline, thin walled essential mycelium which has a short life in nature. 

Auxiliary mycelium: The essential hyphae or mono karyotic hyphae with (+) or (- ) strain haploid cores interact with one another to frame dikaryotic or heterokaryotic mycelium by two techniques : - 

i. Somatogamy: The substantial cells ( vegetative cells) of essential or mono karyotin hyphae of inverse srains (+ and - ) when they interact with one another straightforwardly on the base , the cell divider between the two cells ( + and-) disintegrates , combination of two cellular materials ( plasmogamy) happens, two cores (+and-) lie close to one another to frame a dikaryotic, haploid cell (Somatogamy) . 

This dikaryotic (n) cell goes through various mitotic divisions to frame flimsy walled, multicellular, expanded optional mycelium. Every phone of this mycelium convey two hereditarily particular (viable) cores (+ and-) and is carefully heterokaryotic, dikaryon. fig. 

ii. Clamp association: This strategy is normal to create heterokaryotic, auxiliary mycelium from essential mycelium of inverse mating types. In this cycle the two viable cells of inverse strain (+&-) of monokaryotic hyphae interact with one another, the cell divider between them breaks up, atomic relocation happens . 

The core of this dikaryotic cell separates mitotically and the girl core relocates in the adjuscent cell with the assistance of a trademark structure or an association for example a short appressed hyphal branch which sidesteps the cross over septum and interfaces the two adjuscent little girl cells along the side called Clamp ( or clasp) association. It sister a technique which guarantees that when a dikaryotic mycelium partitions, every phone of these hyphae will contain two hereditarily unmistakable cores. 

Tertiary mycelium : The dikaryotic, optional mycelium conveying inverse strain( +and-) haploid cores in the hyphal cells branch abundantly by mitosis and the hyphal branches anastomose with one another to shape an intricate tissue of fruiting body (basidiocarp). 

Vegetative or hyphal cell 

The Agaricus hyphal cell comprises of external cell divider (chitin microfibrils and glucan),inner plasma layer (specifically porous), genuine core, haploid of + and - strain or both, cytoplasm, mitochondria, ribosomes, endoplasmic reticulum, golgi mechanical assembly, little vacuoles and glycogen granules as hold food material and so on 

Structure of septum: The septum ( the meeting divider between each hyphal cell of septate hypha ) in every cell of monokaryotic and dikaryotic hyphae of Agaricus is punctured by a tight 0.1-0. 2 ,um width which is encircled by a barrel called septal growing. This sort of septal pore is known as Dolipore septum. This pore is overarched with a punctured cap an expansion of endoplasmic reticulum. This punctured cap is called parenthesome or pore cap which has a few pores in it from which organelles like mitochondria can pass.

Generation 

A biogenetic propagation 

The types of Agaricus go through abiogenetic generation infrequently. It produces two kinds of a biogenetic spores for example odium (slender walled, divided spore), and chlamydospores (thick walled, resting spore). 

Odium or divided spore : 

Oidial or arthro spores are dainty walled, hyaline, divided, spores which are created by the disintegration of center lamellar divider between the adjacent cells on the airborne parts of mono karyotin and dikaryotic hyphae. The mono karyotic odium wires with the hyphal cell of the contrary strain to frame the auxiliary heterokaryotic mycelium .The oidial of dikaryotic type sprout straightforwardly to give rise heterokaryotic mycelium eg. Coprinus lagopus. These kind of spores are created during good conditions i.e temperature 10 - 15Oc , relative moistness 80-90% and ph 6-6.5 . 

Chlamydospores or resting spores: 

It is a thick walled resting spore or perennating spore (seed like) delivered during horrible conditions (drying of base, ascent in temperature, and change in ph). The hyphal cells free additional dampness content, glycogen particles (hold food) get changed over into fat beads, cell divider gets thickened by chitin affidavit. These spores created in chains are at first light shaded yet later become dull earthy colored, get isolated from the remainder of the parental mycelium also, perennate in horrible conditions in the dirt or on the foundation, eg. Coprinus lagopus (Lewis 1961) and Volvariella volvacea (Chang and Yan 1971) . Chlamydospores during blustery season grow by retaining dampness and minerals from the base at 10-20Oc , ph 5.8-6.0 and give rise the youthful mycelium on the base. 

Sexual Reproduction 

Agarics doesn't have all around characterized sex organs or sexual gametes. The substantial or vegetative cells of essential hyphae of inverse mating types (+&-strains ) work as sexual gametes. The two substantial cells of haploid essential hyphae of inverse strains (+&-) interact with one another by a cycle of Somatogamy, iodization or by clip association and combination of cellular materials ( plasmogamy) bring two viable cores (+&-) close to one another. Homothallism is uncommon in agaric ales eg. (Coprinus sterculinus). A large portion of the species display either unifactorial or bifactorial homothallism . The two critical advances that is karyogamy (atomic combination of inverse mating +&-strains) and meiosis ( decrease devision) occur in the basidial cells of ripe layer (hymenium) of fruiting body for example basidiocarp . The basidiospores (meiotic ) are delivered on the probasidial cells exogenously at the abaxial(ventral) surface of the basidiocarp . 

Basidiocarp 

Mineral supplements (ammonium salts and so on) and air circulation. 

These conditions favor the arrangement of fruiting bodies or the basidiocarp on the base. The underlying strides in fruiting body development are : 

1. An multifaceted hyphal grid is framed by the connection of hyphal branches . 

2. From this hyphal cross section the pack of flying hyphae show up which in the end produce a round collection of firmly intertwined hyphae to frame a catch or a bud like structure, creamish white in shading called bud primordium ( first basidiocarp stage) on the foundation. 

3. The bud primordium fills in size and as it arrives at 1.0 mm in measurement , a possible stipe, hymenium (ripe layer) and terminal pileus (cap) get separated all the while . 

4. The stretching of stipe, extension of terminal pileus in to upper (adaxial)smooth and lower(abaxial)infolded gilled lamellar structure and creation of basidiospores happen quickly and significantly in the existence pattern of Agaricus . 

Hemiangiocarpous development

The hemiangiocarpous basidiocarp improvement is portrayed by the accompanying realities: 

The hymenium or prolific layer is encased by tissues (tertiary mycelium) of the basidiocarp in any event, during beginning phases of its turn of events . 

The edge of the pileus is associated with the Basel stipe by a film called inward shroud . 

The hymenium stays encased till the terminal cap (pileus) grows and develops . 

The shroud tears from the edge of the pileus without further ado before the spores develop and stays connected to the stipe as a ring or annulus . 

In certain species the shroud tears in such a way that it hangs down from the cap(pileus) like a flimsy cobwebby drapery called Cortina and in others the whole primordium is covered by a general cloak. This all inclusive cloak breaks and leaves a cup formed body around and bulbous base of the stipe. The remaining parts of the pieces of general cloak are viewed as scales on the cap. These highlights help in grouping and distinguishing proof of numerous species as this component is fleeting in different species . 

Gymnocarpous and Pseudoangiocarpous advancement : In these two techniques the hymenial (rich) layer is framed at first outwardly of the fruiting (basidiocarp) body. In gymnocarpous advancement the hymenial tissue isn't covered and stays bare till development. In pseudoangiocarpous strategy the hymenial tissue later gets encased by the improvement of the outgrowth of the incurving edge of pileus and the stipe. The hymenium stays encased till the basidiocarp develops and the pileus grows to uncover the hymenial tissue 

.In these strategies the minimal structures are not seen at the development of the fruiting bodies (basidiocarp). 

Structure of Basidiocarp

The basidiocarp of Agarics which bears basidiospores comprises of the accompanying tissues: 

a) Hymenium: The rich layer of anastomosed optional hyphae is found underneath the pileus (terminal cap). It lines in the gills or lamellae exogenously which hang beneath in the ventral (abaxial) surface of the pileus. 

b) Gills: The gills are the meager portions of tissues which emanate from the edge of the pileus in towards the stipe. The structure and position of the internal edge of gills towards stipe is an important and fascinating element with regards to numerous agaricales for taxonomists. The gills in certain species are liberated from tail while in others they are connected straightforwardly to the stipe called adnate. The decurrent gills are joined and run down the stipe for some distance. 

c) Trauma : The tram ( L. Trama-Woof) is the internal most tissue which lie in the focal point of the gills. It is a significant component of ordered interest Singer (1975). The focal tissue (trama) is of two kinds: 

The trama comprises of plectenchymatous tissue which is comprised of lengthened hyphae. 

The trama tissue contains huge, globose or oval cells called sphaerocysts dispersed along the stretched hyphal cells (eg. Russula and Lactarius ). The trama is encircled on the two sides by the rich layer (hymenium) in which firmly stuffed layer of basidia are sprinkled with basidioles or cystidia or both in certain species . The cystidia are long and stretch out starting with one gill then onto the next to keep the gills separated from one another (Coprinus) . 

Basidium : The basidium is a cell or a structure found at the terminal finish of dikaryotic hypha in the hymeneal layer of the gill exogenously. In the basidial cell the dikaryotic cores combine with one another ( karyogamy) to shape diploid core (2n) which quickly goes through meiosis (decrease division) to frame an unmistakable number of basidiospores (n). Each basidial cell bears an unequivocal number of haploid basidiospores (2 or 4) which at development are coercively shot off to scatter and fall beneath the pileus affected by gravity on the base. In still air these 

haploid basidiospores (+ and-) get saved underneath the pileus in a mass to frame the spore print. 

Basidiospore: The haploid, monokaryotic basidiospore changes in size, shape, shading and is thick walled and multilayered (3-5), eg. three layered in Psilocybe sp . what's more, Agaricus brunnescens (bisporus ). It comprises of cellular material, haploid core (+or - ), ribosomes, mitochondria, lipid bodies, vacuoles, glycogen granules as hold food material . 

The basidiospores display particular tones eg. in Chlorophyllum molybdites spores are green, in Russula sp . the spores are yellow and in other species spores are white, pink, earthy colored, dark and smoky-dim. The spore tone isn't generally equivalent to that of gills and is controlled by making a spore print on white and dark paper . 

Pixie Rings 

The fruiting collections of mushrooms show up in rings on the damp lush green terrains, gardens and on the rotting cellulosic bases in the woods during spring, early summers and winters displaying the creamish white rhizomatous underground fringe mycelial development in plenitude. 

The expression "pixie ring" for these lovely bodies showing up on the ground was at first utilized by early philosophical taxonomists and naturalists for the pixies visiting these territories, moving, meandering around and appreciating around and around the earlier evenings which brought about the presence of these wonderful (youthful unopened flower bud like structures) fruiting bodies on the strides of these pixies in the early hours of the progressive mornings. 

Additionally various accounts of our grannies express the inexplicably rise of white or beautiful fruiting bodies in rings on the lush yards in the early hours of the morning of spring, summer and win.

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