Mushrooms: classification, general characteristics, structural features, methods of reproduction. Principles of classifying mushrooms How mushrooms became a separate kingdom

General characteristics. Mushrooms are a kingdom of living organisms that combine the characteristics of plants and animals.

Brings them closer to plants. 1) the presence of a well-defined cell wall; 2) immobility in a vegetative state; 3) reproduction by spores; 4) the ability to synthesize vitamins; 5) absorption of food by absorption (adsorption). Common with animals is: 1) heterotrophy; 2) the presence of chitin in the cell wall, which is characteristic of the external skeleton of arthropods; 3) the absence of chloroplasts and photosynthetic pigments in cells; 4) accumulation of glycogen as a reserve substance; 5) the formation and release of a metabolic product - urea. These features of the structure and vital activity of fungi allow us to consider them one of the most ancient groups of eukaryotic organisms that do not have a direct evolutionary relationship with plants, as previously thought. Mushrooms and plants arose independently of the different forms of microorganisms that lived in the water.

More than 100 thousand species of mushrooms are known, and it is assumed that their real number is much larger - 250-300 thousand or more. More than a thousand new species are described worldwide each year. The vast majority of them live on land, and they are found almost everywhere where life can exist. It is estimated that 78-90% of the biomass of all microorganisms in the forest litter is accounted for by the fungal mass (approximately 5 t/ha).

The structure of mushrooms. The vegetative body of the vast majority of fungal species is mycelium, or mycelium, consisting of thin colorless (sometimes slightly colored) threads, or hyphae, with unlimited growth and lateral branching.

The mycelium usually differentiates into two functionally distinct parts: substrate, serving to attach to the substrate, absorb and transport water and substances dissolved in it, and air, rising above the substrate and forming reproductive organs.

Reproduction. Fungi reproduce asexually and sexually. Asexual reproduction occurs in parts of the mycelium or individual cells that give rise to a new mycelium. Yeast fungi reproduce by budding.

Asexual reproduction can also be carried out through endo- and exogenous spores. Endogenous spores are formed inside specialized cells - in sporangia. Exogenous spores, or conidia, arise openly at the ends of special specialized outgrowths of the mycelium, called conidiophores. Once in favorable conditions, the spore germinates, and a new mycelium is formed from it.

Sexual reproduction in fungi is particularly diverse. In some groups of fungi, the sexual process occurs by fusion of the contents of two cells at the ends of the hyphae. In marsupial fungi, there is a fusion of the contents of the antheridium and the female organ of sexual reproduction (archegonia), which is not differentiated into gametes, and in basidiomycetes, a fusion of the contents of two vegetative cells, in which outgrowths or anastomoses often form between them.

Mushroom nutrition. For the normal functioning of fungi, ready-made organic nutrients, mineral salts, and vitamins are needed. Some mushrooms use only ready-made compounds. Others can synthesize a significant part of the nutrients themselves, but at the same time they need some additional nutritional components.

Mushrooms absorb nutrients by absorbing them from the entire surface of the body.

Saprophytic fungi secrete a variety of digestive enzymes (from Latin fermentum - "sourdough"), destroying complex organic substances to simple inorganic ones, therefore they actively participate in the circulation of substances. For example, green mold - the penicillium fungus - grows on bread, on raw skin, and rotting fruit.

Predatory fungi from the family of zoo-opagal fungi catch nematode worms and mobile amoebas living in the soil, using their sticky thickenings at the ends of the hyphae or special trap loops that instantly swell and shrink when touched. An animal caught in this way, for example, a nematode, is firmly held (Fig. 123). Threads of hyphae quickly grow into the victim. They secrete enzymes into it, and then the fungus sucks the contents of the body of the nematode.

Symbiont fungi are widely distributed in nature, cohabiting with different types of plants (higher and lower). With higher plants, fungi form a special cohabitation - the so-called fungus root, or mycorrhiza, and with lower plants and cyanobacteria - lichen.

CLASSIFICATION OF MUSHROOMS

On the basis of the types of sexual process, the nature of flagellation in mobile stages (zoospores and gametes), the development of spores of sexual reproduction and other signs, fungi are divided into main classes.

Chytridiomycetes. The mycelium of these fungi is poorly developed or absent. Zoospores and gametes with one posterior flagellum.

Hyphochytriomycetes (Hyphochytriomycetes). The mycelium is poorly developed or absent. Zoospores and gametes with one anterior pinnate flagellum.

Oomycetes. The mycelium is well developed. Non-cellular. Zoospores with two unequal flagella - pinnate and flagella. The sexual process is oogamy.

Zygomycetes. The mycelium is well developed, with few exceptions non-cellular. There are no moving stages. Asexual reproduction in most species with the help of immobile sporangia spores formed inside the sporangia. Less often - with the formation of conidia. The sexual process is zygogamy (the fusion of two gametangia, which are clearly distinguishable in structure from the vegetative hyphae on which they are formed).

Ascomycetes (Ascomycetes). The mycelium is well developed, cellular. There are no moving stages. Asexual reproduction by means of conidia. The sexual process is gametangiogamy. Spores of sexual reproduction are formed endogenously, in bags.

Basidiomycetes (Basidiomycetes) . The mycelium is well developed, cellular (usually dikaryotic). There are no moving stages. Asexual reproduction by means of conidia. The sexual process is somatogamy. Spores of sexual reproduction are formed exogenously, on basidia.

Deuteromycetes, or imperfect mushrooms (Deuteromycetes, Fungi imperfecti). The mycelium is well developed, cellular. Reproduction is only vegetative and asexual, in the latter case with the help of conidia. The sexual process is absent. The group is in its infancy, connected by origin mainly with the two previous classes.

The kingdom Mycetae (mushrooms) is one of the most numerous. Organisms that belong to this group have amazing characteristics, which you will learn about a little later. Mycology is the study of the structure, reproduction and classification of fungi. This is a very interesting science, it is thanks to its development that we can judge these organisms. So, what are the differences between fungi and plants, how are they classified, how does reproduction occur, and what is their structure?

Mycelium

The classification of fungi is very extensive, but there is such a feature that is characteristic of almost all organisms belonging to this kingdom - this is mycelium. A complex system of threads that perform the function of absorbing nutrients is a feature that is unique to fungi. Threads called hyphae are surrounded by rigid walls of chitin or cellulose. They also contain polysaccharides - carbohydrates similar in composition to starch.

Hyphae transport micro- and macrosubstances to all parts of fungi. With their help, the formation of reproductive structures, represented by sporophores, takes place. Sometimes they are called fruiting bodies. Inside are spores that provide reproduction of fungi. The signs of the classification of fungi are based on the differences in spores in species. Mycelium is a distinctive feature characteristic of all representatives of the Mycetae kingdom, with the exception of yeast and slime molds. Yeasts are unicellular organisms that do not contain hyphae. Slime molds have hyphae, but their development has stopped at the "creeping" stage.

Differences from plants

A general description of fungi will be incomplete if you do not talk about the main differences between these organisms and plants. First, they lack chlorophyll. This is a pigment that is inherent in all representatives of the flora. With its help, the process of photosynthesis takes place - the formation of organic substances from minerals with the release of oxygen, which is necessary for the respiration of all living organisms on the planet.

Classification

Mushrooms are divided into groups according to the type of spores. They can be formed sexually or asexually. The classification is influenced by the structure of spore-bearing structures. For systematization, it is customary to use symbols - endings. The highest rank in the classification of fungi are divisions (they are characterized by the ending -mycota), followed by subdivisions (-mycotina), classes, orders, and families with endings -mycetes, -ales and -aceae, respectively. In genera and species, such "insignia" are absent.

The classification of fungi may differ in different publications, since mycologists have not yet come to a consensus about their hierarchical rank. Slime molds are not considered true mushrooms. There are several subdivisions, each of which has its own name.

Oomycetes

This group of organisms is one of the most controversial in matters of taxonomy. Previously, oomycetes were classified as fungi, but then they were transferred to the kingdom of protists. These are mycelial organisms that live mainly in the aquatic environment. They reproduce asexually, producing motile zoospores or flagellar spores.

According to the classification of oomycetes, pathogens of diseases dangerous for plants belong to this group. They can cause root rot in poorly drained soil, leading to the development of vascular necrosis of the shoots. This is a serious problem faced by greenhouse and nursery owners. Others are the causative agents of diseases such as late blight (potato plague).

It was known about him back in 1845-1847. At this time in Ireland, there was a large-scale loss of the potato crop, which caused a terrible famine. As a result, the population of the country decreased by 1.5 million people. Residents of Ireland were forced to emigrate en masse to North America.

Oomycetes were excluded from the number of fungi, despite the presence of a developed mycelium. Of all the fungi, only representatives of chytridiomycetes and they have mobile zoospores. Oomycetes lack chitin, and the mechanism of lysine biosynthesis is similar to that in plants, and besides, they have a mitochondrial ultrastructure, which is absolutely not characteristic of fungi. Based on all this, at the end of the 20th century, the classification of fungi was finalized, and the oomycetes of their kingdom were excluded.

marsupial mushrooms

According to the classification of mushrooms, the Department of Marsupials (Ascomycetes) is the most extensive (32 thousand species). All organisms that are usually attributed to this group form special sexual spores - ascospores. They are formed in a sac-like cell, that is, a bag (ascoma). As a rule, 8 spores ripen in a bag, but in some types of mushrooms their number can reach a thousand. The spore-bearing layer, hymenium, is located inside the asocarp or fruiting body.

The principles of classification of fungi are based on the commonality of the structure of organisms and their characteristics. Thus, marsupials develop in many environments, including soil, salt and fresh water, plant and animal remains. Some pathogens found in marsupials can cause serious diseases in flora and fauna. The division of marsupials, including yeast, also belongs.

Glossy fungi: structure and classification

It is a subclass of Ascomycetes. By the name of this group, one can understand what is the peculiarity of the organisms belonging to it. Ascomas are not enclosed in fruiting bodies. The most famous representatives of the fungi are yeasts, which are used in the food industry for baking bakery products and fermenting wines. Some types of yeast are widely used in the brewing industry.

Discomycetes

Previously, the order or class of marsupials, and now - a non-taxonomic group, uniting more than four thousand species. The principles of classifying fungi, as you already understood, are based on differences in their structure and reproduction. Discomycetes are characterized by an open fruiting body. This feature is common to all mushrooms belonging to this group, except for truffles. Discomycetes grow in many environments, including soil, manure, and organic matter.

Some fungi cause brown rot on fruit trees or cause maple tar spot. The benefits come from organisms that enter into a symbiotic relationship with algae, form lichens and inhabit stone environments.

Pyrenomycetes or Sordariomycetes

A class of fungi belonging to the department Ascomycetes. Fruiting bodies, similar to a flask, can have a different color, shape and texture. Sometimes fruiting bodies are collected in groups, in other cases they are located singly. Perithecia can be found in stroma - compact structures formed by hyphae.

Pyrenomycetes cause all sorts of diseases in higher plants, including root rot of fruit trees and apple tree cancer. Some species destroy wood, while others infect crops. Flour made from cereals attacked by these fungi poses a serious threat to human health and causes ergotism - food toxicosis. Alkaloids cause a strong muscle contraction and at high concentrations lead to death, at low concentrations - mental disorders, aggressive behavior, severe pain and gangrene.

basidiomycetes

Organisms included in this group have the following distinguishing feature: sexual spores, which are commonly called basidiospores, ripen on the surface of the basidia. Each of them is formed by a swollen cell located at the end of the hypha, and thin outgrowths. They contain basidiospores.

This section includes a large number of organisms. A common characteristic of mushrooms belonging to this group is that they all have large, rather fleshy fruiting bodies. Among the most well-known basidiomycetes are vesicles, tinder fungi, puffballs, and tremors. They are, for the most part, saprotrophs and contribute to the faster decomposition of dead wood, manure and leaf litter.

There is a classification of mushrooms into categories "edible" and "inedible". The first group includes, for example, such organisms as the real chanterelle and white fungus, known to everyone. Among the most common poisonous mushrooms are the red fly agaric and the semi-lanceolate psilocybe.

There are three subdivisions of basidiomycetes and one class not included in any of them. According to 2008 data, there are 31,515 species of basidiomycetes discovered in the world, which are combined into 1589 genera, 177 families, 52 orders and 16 classes. Three subdivisions:

It occupies an unexplained position in the system of the class Vallemyomycetes.

Zygomycetes (Zygomycota)

The structure and classification of fungi in this department have not been studied enough. It is known that they are distinguished by a developed mycelium, which has a variable thickness, septa are formed in it only after the further separation of the reproductive organs.

These terrestrial fungi reproduce in two ways. During asexual reproduction, the formation of spores incapable of movement occurs. Sexual is characterized by the fusion of gametangia, which are located on the mycelium. As a result of this, a zygospore is formed, which does not germinate immediately, but some time after formation. Spores appear in sporangia, sometimes they are thrown into the air.

Features of the classification of fungi are quite complex. Regarding some departments, classes and types, there is still no consensus on the port. Among them is the department of Zygomycetes, which is considered a polyphyletic or paraphyletic group of organisms. The exact systematic position of its species has not yet been established. The department is not divided into classes. All species are divided into 10 orders, which are very conditionally combined into four subdivisions.

Fungal halide spores have only one flagellum. They can either give rise to a new organism or merge, forming a diploid organism that forms new haploid zoospores.

Deuteromycetes

Their second name is imperfect mushrooms. They reproduce by propagules, which are formed bypassing the process of meiotic division. Propagules, as a rule, are conidia, in rare cases they form from undifferentiated mycelium.

Fungi of this group are widespread, some species cause crop diseases, others are of great economic importance. It is to this group that Aspergillus and Penicillium belong, which are used as producers of enzymes and antibiotics.

Having studied the general characteristics and classification of fungi, it becomes clear that these are amazing organisms, the nature of which has not yet been fully studied, which greatly complicates the systematics.

Mushrooms are a large and ubiquitous group of very diverse organisms that can exist in a wide range of conditions. The science that studies them is called mycology, and specialists in this field are called mycologists. Once upon a time, fungi were included in the plant kingdom and, together with bacteria, algae and lichens, constituted a department of lower, thallus, or thallus, plants (Thallophyta). With further study of these four groups, they were all distributed to other kingdoms, and the previous classification was considered obsolete.

The unique features of mushrooms justify their allocation to an independent kingdom Mycetae or Fungi. Now many mycologists believe that the organisms included in it are too diverse, and some groups traditionally related to fungi are transferred to other kingdoms. In particular, slime molds (Myxomycota), with their characteristic amoeboid feeding stage, are increasingly considered to be part of the protist kingdom (Protista).

Mycelium. Despite all the diversity of fungi, the vast majority of them have a feature specific to this group - mycelium, i.e. a system of threads that absorb nutrients. The threads themselves are called hyphae; each of them is surrounded by a fairly rigid wall of chitin and (or) cellulose in combination with other polysaccharides (carbohydrates similar in molecular structure to starch). Hyphae serve not only for nutrition: they form special reproductive structures - sporophores or "fruiting bodies", and spores on them or inside them. Mycelium is one of the most important distinguishing features of fungi, however, yeast and slime molds are an exception: they do not usually have single-celled and true hyphae, and the latter are distinguished by the presence of a “creeping” amoeboid stage in the development cycle.

CLASSIFICATION

Mushrooms are classified according to the type of spores (they are formed sexually or asexually) and the structure of specialized spore-bearing structures. The hierarchical rank of fungal taxa is indicated by the standard endings recommended for these organisms by the international rules of botanical nomenclature.

The highest ranking taxa within the kingdom of fungi - divisions (they are equivalent to "types" in animals) - should have an ending -mycota, and subdivisions (second in the hierarchy) -mycotina. Next in descending order are classes (-mycetes), orders (-ales) and families (-aceae). There are no standardized endings for genera and specific epithets.

Regarding the details of the classification of fungi, disagreements remain among mycologists, and the same groups can be combined, divided, or changed their hierarchical rank by different authors. However, now it is generally accepted not to classify slime molds and a number of other “problematic” forms as “real mushrooms” (Eumycota department), and five subdivisions are usually distinguished among the former: Mastigomycotina, Zygomycotina, Ascomycotina, Basidiomycotina and Deuteromycotina.

Mastigomycotina ("flagellate mushrooms").

Zygomycotina.

These are terrestrial fungi, the asexual reproduction of which occurs with the formation of immobile spores (aplanospores), and the sexual one - by merging the "genital organs" growing on the mycelium, called gametangia. Aplanospores mature in sac-like structures - sporangia and, in a number of species, are thrown out of them with force into the air. During sexual reproduction, the fusion and mixing of the contents of the gametangia leads to the formation of a thick-walled zygospore, which germinates after a more or less long dormant period. The best known in this department are the genus Mucor and fungi close to it, abundantly represented in the soil, on manure and other organic residues, often growing in the form of a fluffy coating on raw bread and rotting fruits. The structure of sporangia and the mode of development of the zygospore vary widely and serve as the basis for the identification of various taxa. Many representatives of this subdivision are heterothalmic, i.e. the sexual process and the formation of zygospores are possible in them only when they meet individuals of the same species belonging to different "sex types" (they are denoted by + or -). Their "intersexual" relationships are coordinated by special substances of a hormonal nature released into the environment. The presence of two sexual types is reflected in the name of the subdivision, formed from the Greek. zym - "pair".

Ascomycotina (marsupials).

This is the most extensive group of fungi, which differs from others in a special type of sexual spores - ascospores, which are formed inside a sac-shaped cell called a bag, or ascom (from the Greek askos - “bag”). Usually eight ascospores ripen in an ascus, but depending on the type of mushrooms, there can be from one to more than a thousand of them. The densely packed asci (often interspersed with sterile filaments) form a spore-bearing layer called the hymenium.
In most marsupials, it is located inside a specific accumulation of hyphae - the fruiting body, or ascocarp. These are complex structures, on the features of which the classification of representatives of this subdivision is largely based. Most marsupials also form asexual aplanospores, called conidiospores or simply conidia (from the Greek konis - dust, and idion - a diminutive suffix, i.e. "tiny speck of dust"). Conidia mature either on the usual (somatic) hyphae that make up the body of the fungus, or on specialized hyphae-stands (conidiophores).

Marsupials occupy many ecological niches. They are found in the soil, in the seas and fresh water bodies, on the decaying remains of animals and plants. Many among them are dangerous pathogens that cause various diseases of plants and animals.

Traditionally, this largest subdivision of fungi is divided into five classes: Hemiascomycetes, Plectomycetes, Pyrenomycetes, Discomycetes and Loculoascomycetes, however, the emergence of new electron microscopic data and the results of DNA typing (analysis of genetic material) suggest that such a classification scheme does not reflect true evolutionary relationships.

Plectomycetes.

Pyrenomycetes.

In these mushrooms, cylindrical asci are usually found in fruiting bodies called perithecia, which outwardly resemble a flask and open into the environment with a hole at the end of a narrowed neck. Perithecia vary greatly in shape, color and consistency, they are single or collected in groups, sometimes immersed in special compact structures formed by hyphae called stroma. So, in the species Sordaria fumicola, which is usually found on manure, the perithecia are solitary, approx. 0.5 mm, and in Daldinia concentrica, hundreds of fruit bodies are located along the periphery of the stroma, sometimes more than 2.5 cm in diameter, divided into clear concentric zones. Some pyrenomycetes cause plant diseases, such as white rot of fruit tree roots (Rosellinia necatrix) and apple tree cancer (Nectria galligena); other species can be harmful by destroying wood. Ergot purple (Claviceps purpurea) affects ears of rye and other grains. Eating flour contaminated with this fungus causes a serious illness - ergotism - with symptoms such as hallucinations and a strong burning sensation (hence the old name for the disease - "Anton's fire").

Discomycetes.

In discomycetes, the fruiting body is usually open, cup-shaped or disc-shaped with hymenium on the surface. An exception is representatives of the truffle order (Tuberales), which form underground ascocarps with internal hymenium. The division of discomycetes into taxa of the lowest rank is largely based on the method of opening the ascus. At the so-called. operculate asci have a special lid for this, while inoperculate asci do not have such a lid. Most discomycetes are saprotrophs growing on soil, manure and plant litter. Some genera are pathogenic, for example, Sclerotinia fructigenia causes the common brown rot of apples and pears, and Rhytisma acerinum causes maple tar spot. The highly specialized order Lecanorales includes species that form (in symbiosis with algae) most lichens; the latter play an important role in colonizing rocks, bare ground, and other extremely harsh habitats.

Loculoascomycetes.

These mushrooms are characterized by the so-called. bitunicate, i.e. surrounded by a double shell, asci. The outer rigid wall (exoask, or exotunica) ruptures when they ripen, the inner tensile wall (endoask, or endotunica) protrudes through the hole formed, and only after that spores are released into the environment. The name of the class is due to the fact that asci develop in cavities (locules) within the fruiting bodies, commonly called ascostromes.

Basidiomycotina (basidiomycetes).

A distinctive feature of these fungi is the maturation of sexual spores (basidiospores) on the surface of special structures, the so-called. basidium. Each of the basidia is formed at the end of the hyphae and is a swollen cell (rarely four cells) with thin outgrowths (sterigmas), to which the basidiospores are attached.

Deuteromycotina.

This group is also called Fungi imperfecti, i.e. "imperfect fungi", since sexual reproduction and related structures are unknown in them. The taxonomy of such fungi is based on the way their asexual spores (conidia) are formed. The group, in principle, is artificial, in some of its representatives, sexual forms are found over time, and as a result, the same species can be described under different names, for example, both as an imperfect (asexual, or anamorphic, stage) and as a marsupial (sexual , or teleomorphic stage).

General characteristics. Mushrooms are a kingdom of living organisms that combine the characteristics of plants and animals.

Brings them together with plants -. 1) the presence of a well-defined cell wall; 2) immobility in a vegetative state; 3) reproduction by spores; 4) the ability to synthesize vitamins; 5) absorption of food by absorption (adsorption). Common with animals is: 1) heterotrophy; 2) the presence of chitin in the cell wall, which is characteristic of the external skeleton of arthropods; 3) the absence of chloroplasts and photosynthetic pigments in cells; 4) accumulation of glycogen as a reserve substance; 5) the formation and release of a metabolic product - urea. These features of the structure and vital activity of fungi allow us to consider them one of the most ancient groups of eukaryotic organisms that do not have a direct evolutionary relationship with plants, as previously thought. Mushrooms and plants arose independently of the different forms of microorganisms that lived in the water.

More than 100 thousand species of mushrooms are known, and it is assumed that their real number is much larger - 250-300 thousand or more. More than a thousand new species are described worldwide each year. The vast majority of them live on land, and they are found almost everywhere where life can exist. It is estimated that 78-90% of the biomass of all microorganisms in the forest litter is accounted for by the fungal mass (approximately 5 t/ha).

The place of mushrooms in the organic world In the history of the development and formation of biology, the question of determining the place of fungi among other biological objects has been debatable until recently. Systematists and florists involved in biodiversity have always considered fungi with reservations as part of the plant kingdom, in the Tallophyta subdivision, as a special class of plants, along with bacteria, lichens, and algae. In the second half of the twentieth century. works appeared in which an analysis of modern knowledge about the structure and similarity of the evolution of cell ultrastructures of living organisms was given. Based on this, Whittaker (Whittaker, 1969) proposed a system of the organic world, including five kingdoms. It adopted an independent kingdom of fungi (Fungi), separate from the kingdoms of animals (Animalia) and plants (Plantae). Thus, only in the second half of the twentieth century. the position on the phylogenetic independence of fungal organisms becomes generally recognized. It turned out that all living organisms of the Earth are built according to a single plan. The most important ultrastructures of eukaryotic organisms include several organelles: karyomes, mitochondria, cilia (flagella, undulopodium) and photosynthetic plastids. Features of their structure, role in the life support and evolution of organisms turned out to be the most significant features and later became the basis of the megasystematics of all eukaryotes. In later years, a large number of kingdoms and divisions within them were proposed. In addition, numerous theories of the evolutionary development of the biota have been developed and continue to be developed. One of them - the theory of the symbiogenetic origin of the eukaryotic cell through the gradual symbiosis of microbial associations - gave impetus to the construction of numerous schemes of the organic world. The most accessible seems to be the five-kingdom system of the structure of the organic world: I. The super-kingdom of pre-nuclear organisms, or prokaryotes (Procariota) 1. The kingdom of monera (Monera) II. Superkingdom nuclear organisms, or eukaryotes (Eucariota) 2. Kingdom of protists (Protoctista) 3. Kingdom of fungi (Fungi) 4. Kingdom of animals (Animalia) 5. Kingdom of plants (Plantae) The evolution of microbial associations has led to the fact that the difference between eukaryotic cells ( protists, fungi, plants and animals) and prokaryotic cells devoid of a real nucleus are deeper than between the listed groups of eukaryotes. The world was divided into two parts, there was a fundamental distinction in living nature - the distinction between prokaryotes and eukaryotes.

Principles of classification of mushrooms.

Mushrooms belong to the kingdom Fungi(Mycetes, Mycota). These are multicellular or unicellular non-photosynthetic (chlorophyll-free) eukaryotic microorganisms with a cell wall.

mushroom classification. Mushrooms can be divided into 7 classes: Chytridiomycetes, Hyphochytridiomycetes, Oomycetes, Zygomycetes, Ascomycetes, Basidiomycetes, Deuteromycetes.

Among phycomycetes distinguish:

1) chytridiomycetes, or aquatic fungi that lead a saprophytic lifestyle or infect algae;

2)hypochytridiomycetes, resembling chytridiomycetes and oomycetes;

4) zygomycetes include representatives of the genus Mucor, common in soil and air and capable (for example, fungi of the genus Mucor) to cause mucormycosis of the lungs, brain and other organs.

At asexual reproduction on the fruit-bearing hyphesporangiophore is formed sporangium- a spherical thickening with a shell containing numerous spores (sporangiospores).

Sexual reproduction (oogamy) in zygomycetes are carried out by the formation zygospore or oospore.

Eumycetes are represented by ascomycetes and basidiomycetes. (perfect mushrooms), as well as deuteromycetes(imperfect mushrooms). Ascomycetes(or marsupials) unite a group of fungi that have a septate mycelium and are distinguished by their ability to reproduce sexually. Ascomycetes got their name from main fruiting organ - bags, or asuka containing 4 or 8 haploid sexual spores (ascospores). Ascomycetes are members of the genera Aspergillus, Penicillium and others, differing in the features of the formation of fruiting hyphae.

At Aspergillus(water mold) at the ends of the fruiting hyphaconidiophores there are thickenings - sterigmas, on which chains of spores - conidia are formed. Some types of aspergillus can cause aspergillosis and aflatoxicosis.

Fruiting hypha in fungi of the genus Penicillium(racus) resembles a brush, since thickenings are formed from it (on the conidiophore), branching into smaller structures - sterigmas, on which there are chains of conidia. Penicillium can cause disease (penicillinosis). Many species of ascomycetes are producers of antibiotics.

Representatives of ascomycetes are and yeast- unicellular fungi that have lost the ability to form true mycelium. Yeast have oval-shaped cells with a diameter of 3-15 microns. They are reproduce by budding, binary fission(divided into two equal cells) or sexually with the formation of ascospores. Yeast is used in biotechnological processes. Diseases caused by certain types of yeast are called yeast mycoses.

Basidiomycetes - hat mushrooms with septate mycelium.

Deuteromycetes - imperfect mushrooms(Fungi imperfecti) - are a conditional class of fungi that combines fungi with septate mycelium, not having sexual reproduction. They reproduce only asexually, forming conidia. Imperfect fungi include fungi of the genus Candida affecting the skin, mucous membranes and internal organs ( candidiasis). They are oval in shape, 2-5 microns in diameter; divide by budding (blastospores), form pseudomycelium (budding cells from the germ tube are drawn into a thread), at the ends of which are chlamydospores. These mushrooms are called yeast-like. True yeast (ascomycetes) form ascospores, do not have pseudomycelium and chlamydospores. The vast majority of fungi that cause disease in humans (mycoses) are imperfect fungi.