"Reserve substances" - the term is not too precise, if they refer to substances stored for the future for their further use, since their origin and functions are not always unambiguous. Some antibiotics can also be included in their number, as accumulated in large quantities polyacetylenes, pigments and waste products and their resynthesis products from other biosynthetic processes, such as volutin. In this case, we will only talk about reserve substances for direct use, i.e., carbohydrates, fats and urea.

Of the carbohydrates localized in fungal cells, they are characterized by glycogen, mannitol, and the disaccharide trehalose (or mycosis). The amount of glycogen in the fruiting bodies and mycelium of fungi can vary from 1.5 to 40% depending on the type of fungus and the age of the fruiting body. In young fruiting bodies and cultures of fungi, it is correspondingly higher by an order of magnitude than in old ones with mature spores.

Trehalose, a disaccharide (α-D-glucoside-α, D-glucoside), is usually found in small amounts, more often in tenths of a percent relative to the mass of dry mycelium, but sometimes its amount reaches 1-2%. Apparently, its use is associated with the accumulation of hexatomic alcohol, mannitol, which can accumulate up to 10-15% in the fruiting bodies of fungi, especially in the hymenium of basidiomycetes. It is found in significant quantities in species of the genus Boletus (B. scaber, B. aurantiacus, B. crassus). Mannitol is more characteristic of more mature mycelium and fruiting bodies, as can be seen from the example of fruiting bodies. phallus impudicus in which it predominates over trehalose. Apparently, during the metabolism of trehalose in these fruiting bodies, mannitol can be synthesized. Both trehalose and mannitol among other organisms are characteristic mainly of insects.

Of other substances, the mycelium of fungi often contains a lot of fat, which accumulates in the form of teardrop-shaped inclusions, which can be consumed by fungi during growth or sporulation. In the young mycelium of Penicillium chrysogenum, its amount can reach up to 35%, while in the aging mycelium it drops to 4-5% of the mass of dry mycelium.

Mushroom fats typically have a high content of unsaturated fatty acids, oleic, linoleic, linolenic and others, liquid at room temperature, and a large number of unsaponifiable lipids, i.e. steroids. In the mycelium of Penicillium chrysogenum, the amount of ergosterol-type steroids reaches 1% of the mass of dry mycelium. There is reason to believe that in some fungi, at certain stages of their development, steroids can be up to 80% of the composition of their fat fraction, and often this is biologically active substances, toxins or vitamins.

The accumulation of fats in fungi often depends on the age of the culture or on the composition of the nutrient medium, in particular on the presence of carbohydrates in it. As noted, with an increase in the concentration of glucose in the medium, the amount of fatty substances increases. Although there is no direct correlation between the accumulation of fats and an increase in the concentration of glucose, in order to double the amount of fatty substances in the mycelium of a wood-destroying fungus, it turned out to be necessary to increase the concentration of sugar in culture medium from 10 to 40% (Ripachek, 1967).

About 100,000 fungal species have been described so far, but some estimates may be as high as 1.5 million.

Systematics

Kingdom Mushrooms

Subkingdom Mushrooms

Subkingdom True Mushrooms (do not form motile cells at any stage of the life cycle)

Division Zygomycetes (belong to lower fungi)

Division Ascomycetes, or Marsupials

Department of Basidiomycetes

Department of Deuteromycetes (Imperfect fungi)

The body of the mushroom consists of long filaments - gif.

The hyphae grow apically (apically) and can branch to form a dense intertwined network -- mycelium, or mycelium.

Mycelium is located in the substrate (soil, wood, living organism) or on its surface.

The growth rate of mycelium depends on environmental conditions and can reach several centimeters per day.

In basidiomycetes, the mycelium is often perennial, in other fungi it is annual. Since the mycelium grows apically, its growth is centrifugal. The oldest part of the mycelium in the center gradually dies off, and the mycelium forms a ring. In addition, some fungi secrete substances that prevent plant growth (amensalism), and the vegetation cover forms rounded "bald spots".

Rice. "Witch Ring"

MYCELIUM TYPES

  • non-cellular (non-septate) mycelium: formed by one multinucleated giant cell (for example, in zygomycetes);
  • cellular (septated) mycelium: there are intercellular partitions (septa); cells are mononuclear or multinuclear. INopenings may remain in cell partitions through which the cytoplasm and organelles (including nuclei) freely flow from cell to cell.

Ascomycetes dikaryotic mycelium(consists of binuclear cells).

Rice. Mycelium: 1 - unicellular (non-septate); 2 - multicellular (septate); 3 - dikaryotic (yeast).

Fruit bodies of basidiomycetes are formed by false tissue plectenchyma(pseudoparenchyma), consisting of densely intertwined hyphae of the mycelium. Plectenchyma, unlike ordinary parenchyma, is formed not by three-dimensionally dividing cells, but by strands of hyphae.

Hyphae are able to combine into long strands - rhizomorphs(ancient Greek - root-like form): the outer cells of the strand are denser and perform a protective function, the inner, more delicate cells perform a conductive function.


Rice. rhizomorphs

To endure adverse conditions, many mushrooms form dense rounded bodies formed by a plexus of hyphae - sclerotia(ancient Greek - solid). Outside, the sclerotia are covered with a hard dark shell that protects the inner light tender hyphae containing nutrients. Germinating, sclerotia give rise to mycelium; sometimes a fruiting body is immediately formed from them.

Rice. Ergot sclerotia

sclerotia

GIF FUNCTIONS (MYCELIUM):


Physiology of mushrooms

NUTRITION OF MUSHROOMS

According to the sources of organic substances used, fungi are divided into 4 groups.

Molecules of organic substances that make up living organisms and their residues cannot pass through the cell wall of fungi, so fungi secrete digestive enzymes into the substrate. These enzymes break down organic substances into low molecular weight compounds that the fungus can absorb on its surface (osmotrophic type of nutrition).This way it happens external digestion mushrooms.

  • Predatory mushrooms: they actively catch prey with the help of modified hyphae (trapping loops, etc.).
  • Symbiotic mushrooms: enter into symbiosis with various autotrophic organisms(lower and higher plants), receiving organic substances from them, and in return supply them with mineral nutrition.

SYMBIOSIS

  • Mycorrhiza (mushroom root): symbiosis of fungi with the roots of seed plants.
    Since the area of ​​absorption of fungal hyphae is much larger than the area of ​​the absorption zone of roots, the plant receives much more minerals, which allows it to grow more actively. The plant, in turn, gives the fungus part of the carbohydrates, the products of photosynthesis.



Rice. Mycorrhiza

MUSHROOMS-SYMBIONTS

REPRODUCTION OF MUSHROOMS

Asexual reproduction:

  • multicellular and unicellular parts of the mycelium
  • spore formation
    endogenous spores (sporangiospores) are formed in sporangia
    exogenous spores (conidiospores = conidia) are produced in conidia
  • budding (in yeast)

Rice. Mold sporulation: penicillium (a) and aspergillus (b) conidia; sporangiospores mucor (c)

sexual reproduction:

Real fungi do not have mobile cells, so the fusion of the cells of two individuals occurs through the growth and convergence of hyphae.

  • fusion of gametes formed in gametangia (isogamy, heterogamy, oogamy);
  • somatogamy: the fusion of two cells of the vegetative mycelium;
  • gametangiogamy: the fusion of two sexual structures that are not differentiated into gametes;
  • chologamy: cell fusion of unicellular fungi.

In addition to asexual sporulation, fungi also have sexual sporulation: the formation of spores by meiosis after the fusion of the genetic material of gametes or nuclei.


Rice. Mucor and its sporangium

REPRODUCTION OF MUCORA

Division Ascomycetes (Marsupials)

  • About 30,000 species.
  • Saprotrophic soil and mold fungi that settle on bread, vegetables and other products.
  • Representatives: penicillium, yeast, morels, lines, ergot.
  • Mycelium haploid, septate, branching. Through the pores, the cytoplasm and nuclei can pass into neighboring cells.
  • Asexual reproduction using conidia or budding (yeast).
  • During sexual reproduction, bags (asci) are formed, in which, during meiosis, haploid spores of sexual sporulation are formed.

YEAST

Yeasts are represented by a large number of species widely distributed in nature.

Unicellular or bicellular fungi, the vegetative body of which consists of mononuclear oval cells.

Different types of yeast can exist in diploid or haploid phases.

Yeasts are characterized by aerobic metabolism. They use various sugars, simple and polyhydric alcohols, organic acids and other substances as a carbon source.

The ability to ferment carbohydrates, breaking down glucose to form ethyl alcohol and carbon dioxide, served as the basis for the introduction of yeast into culture.

WITH6 H12 ABOUT6 С6Н12О6 → 2 WITH2 H5 ABOUTH 2C2H5OH + 2 WITHABOUT2 2CO2

Yeast reproduces by budding and sexually.

Under favorable conditions, yeast reproduces vegetatively for a long time - by budding. The kidney arises at one end of the cell, begins to grow and separates from the mother cell. Often the daughter cell does not lose its connection with the mother cell and begins to form buds on its own. As a result, short chains of cells are formed. However, the connection between them is fragile, and when shaken, such chains break up into separate cells.

With a lack of nutrition and an excess of oxygen, sexual reproduction: Two cells fuse to form a diploid zygote. The zygote divides by meiosis to form a bag with 4 ascospores. The spores fuse to form a new diploid yeast cell.

Rice. Budding and sexual reproduction of yeast.

Outwardly, it resembles black-purple horns (sclerotia) protruding from the ear. They consist of densely intertwined hyphae.

Rice. Ergot

ERGO LIFE CYCLE

The binuclear mycelium forms fruit bodies, known as hat mushrooms.

Rice. The structure of cap mushrooms

On the underside of the cap is a spore-forming layer (hymenophore), on which special structures - basidia.

To increase the surface of the hymenophore, Bottom part hats are modified:

  • at agaric the hymenophore has the form of radially divergent plates (russula, chanterelle, mushroom, champignon);
  • in tubular fungi, the hymenophore has the form of tubes that are tightly adjacent to each other (boletus, boletus, butterdish, boletus).

Some fungi produce velum(= velum = cover) - a thin shell that protects in young age fruiting body of the fungus

  • common veil: covering the entire fruiting body;
  • private spathe: covers the lower surface of the cap with hymenophore.

With the growth of the fungus, the covers are torn and remain on the fruiting body in the form of rings and a rim. (volvo) on the stem, various scales and flaps covering the hat. The presence of bedspread remains and their features are important for the identification of fungi.

Rice. The rest of the veil (velum) on the fly agaric

When smut is damaged, instead of grain, black dust is obtained, which is the spores of the fungus. The ears become like charred firebrands. Infection by some species occurs at the flowering stage of cereals, when spores from the affected plant fall on the stigmas of the pistils of healthy plants. They germinate, the hyphae of the fungus penetrate the seed embryo, and a caryopsis is formed, outwardly healthy. On next year by the time of flowering, sporulation of the fungus begins, flowers are not formed, and the inflorescence takes on a charred appearance.

Rice. Smut

Polypores have a tubular perennial hymenophore, which annually grows from below.

A spore of a tinder fungus, hitting a wound in a tree, germinates into a mycelium and destroys the wood.

After a few years, perennial hoof-shaped or disc-shaped fruiting bodies are formed.

Tinder fungi secrete enzymes that break down wood and turn it into dust. Even after the death of a tree, the fungus continues to live on a dead substrate (as a saprotroph), producing a large number of spores annually and infecting healthy trees.

That's why dead trees and fruiting bodies of tinder fungi are recommended to be removed from the forest.


Rice. Pine fungus ( bordered tinder fungus) Rice. Trutovik scaly (variegated)

DEPARTMENT OF DEUTEROMYCETS, OR IMPERFECT FUNGI

  • Deuteromycetes occupy a special position among fungi.
  • They reproduce only asexually - conidia.
  • Mycelium septate.
  • Whole life cycle passes in the haploid stage, without a change in nuclear phases.

These fungi are "former" ascomycetes or, more rarely, basidiomycetes, which in the process of evolution have lost sexual sporulation for one reason or another. Thus, deuteromycetes represent a phylogenetically heterogeneous group.

mushroom meaning

  • They are the main reducers in the decomposition of wood.
  • They are food for many animal species, being the beginning of detrital food chains.
  • Food product with high nutritional value.
  • Yeast cultures are used in Food Industry(bakery, brewery, etc.)
  • Chemical raw materials for obtaining citric acid and enzymes.
  • Obtaining antibiotics (eg penicillin).

Botany The science that studies the plant kingdom (gr. nerd- grass, plant).

The ancient Greek scientist Theophrastus (III century BC), a student of Aristotle, created a system of botanical concepts, systematizing and summarizing all the knowledge of farmers and healers known at that time with his theoretical conclusions. It is Theophrastus who is considered the father of botany.

modern botany- the science of morphology, anatomy, physiology, ecology and taxonomy of plants

Signs of the Plant Kingdom

  • eukaryotes;
  • autotrophs (the process of photosynthesis);
  • osmotrophic type of nutrition: the ability of cells to absorb only low molecular weight substances;
  • unlimited growth;
  • immobile lifestyle;
  • reserve substance - starch (accumulates in plastids during photosynthesis);

Structural features of a plant cell (Fig. 1):

  • cellulose cell wall
    Availability cell wall prevents the penetration of food particles and large molecules into the cell, therefore plant cells absorb only low molecular weight substances (osmotrophic type of nutrition). Plants absorb from environment water and carbon dioxide, for which the cell membrane is permeable, as well as mineral salts, for which there are channels and carriers in the cell membrane.
  • plastids (chloroplasts, chromoplasts, leukoplasts);
  • large central vacuole
    Bubble with cell sap, surrounded by a membrane - tonoplast. The tonoplast has a system of regulated carriers that carry various substances into the vacuole, maintaining the desired concentration of salts and acidity in the cytoplasm. In addition, the vacuole provides the necessary osmotic pressure in the cell, which leads to the appearance turgor- stress on the cell wall, which maintains the shape of the plant. The vacuole also serves as a storage site for nutrients and waste products of metabolism.
  • There are no centrioles in the cell centers of plants.

Rice. 1. Plant cell

plant classification

The main ranks of plant taxa are distributed according to principle of hierarchy(subordination): larger taxa unite smaller ones.

For example:

Plant Kingdom

department Angiosperms

class Dicotyledonous

Asteraceae family

genus Chamomile

view Chamomile

life form - appearance plants.

Basic life forms: tree, shrub, shrub and grass.

Tree- perennial plant with a large lignified trunk.

Bush- a plant with numerous medium-sized lignified trunks that live no more than 10 years.

Shrub- a low-growing perennial plant with lignified trunks, up to 40 cm high.

Herbs- herbaceous green shoots that die off annually. In biennial and perennial grasses, new shoots grow from wintering buds in spring.

higher and lower plants

Different groups of plants differ significantly in structure.

Lower plants do not have organs and tissues. Their body is thallus, or thallus. The lower plants are algae. Most of them live in aquatic environment. Under these conditions, they receive nutrition by absorbing substances from the entire surface of the body. All or most of the cells of these plants are in the light and are capable of photosynthesis. Therefore, they do not need to quickly move substances around the body. The cells of these plants in most cases have the same type of structure.

Other photosynthetic organisms are also found in the aquatic environment. These are primarily cyanobacteria, which are sometimes called blue-green algae. These are prokaryotic organisms that are not plants.

Algae are often referred to as higher plants that live in water. In these cases, the term "algae" is used in an ecological rather than a systematic sense.

Higher plants have functionally different organs formed by specialized cells. Basically, they live on land. They receive water and mineral nutrition from the soil, and for photosynthesis they must rise above its surface, therefore, for such plants, it is necessary to move substances between parts of the body (conductive tissue) and mechanical support and support ground-air environment(mechanical and integumentary tissues).

The presence of specialized cells, tissues and organs allowed them to achieve large sizes and master a wide range of habitats. Many representatives of higher plants returned to the water for the second time. In fresh water bodies, they make up the bulk of aquatic vegetation.

Mushrooms- one of the largest and most prosperous groups of organisms. These are eukaryotes that do not have chlorophyll, and therefore, they feed on ready-made organic substances, like animals, and glycogen is a reserve nutrient. However, they have a rigid cell wall, they are not able to move, like plants, so they were allocated to a special kingdom.

Mushroom reproduction happens in three ways:

Widely known hat mushrooms- chanterelles, fly agaric, white, milk mushrooms. Their fruiting bodies are represented by a stem and a cap, and consist of tightly fitting mycelium filaments. Hats are dyed. There are tubular cap mushrooms, in which the lower layer of the cap is formed by tubules ( White mushroom, boletus) and lamellar, with a lower layer of plates (russula, chanterelles). Millions of spores are formed in tubules and plates.

mold mushrooms- mucor and penicillium, develop on food residues, in soil, manure, on fruits. Penicillium produces substances that have a detrimental effect on bacteria. They are isolated and used to treat inflammatory diseases. This group also includes yeast - which can form colonies, this is used in baking.

Useful value of mushrooms:

Saprophytic fungi, together with soil bacteria, have an impact on soil formation, as they decompose organic matter into inorganic.
Together with bacteria, saprophytic fungi are used to treat wastewater.
One of the most ancient uses of mushrooms is fermentation.
The most famous varieties of cheese are the product of the simultaneous work of bacteria and various kinds mushrooms.
Obtaining antibiotics - for example, penicillin.
Some mushrooms are the most convenient objects for research and genetic engineering.
They are a cheap source of feed protein.

Harmful value of mushrooms:

Saprophytic fungi, settling on food and various organic materials, can cause spoilage.
causative agents of various diseases.

This group of organisms was previously classified as plants. At present, mushrooms, numbering about 120 thousand species, have been identified as an independent kingdom, since according to a number biological properties they are different from bacteria, plants and animals.

Fungal cells, unlike bacteria, are eukaryotes. They are distinguished from plants by the absence of chlorophyll and the use of ready-made food for nutrition. organic matter, i.e., according to the type of nutrition, they are heterotrophs. The reserve nutrient in mushrooms is glycogen, and not starch, which is characteristic of most plants. According to the method of nutrition (absorption) and unlimited growth, fungi approach plants. With animals they are brought together by the fact that urea is involved in the metabolism. Mushrooms are also characterized by the formation of a pronounced cell wall, reproduction by spores, immobility in the vegetative state, etc.

The classification of fungi is based on the methods of reproduction and morphological features.

The fungi kingdom Mycetalia, Fungi, Mycota is divided into two half-kingdoms: lower fungi (Myxobionta) and higher fungi (Mycobionta).

Lower fungi are characterized by the presence of rudimentary as well as unicellular mycelium. These include mushrooms of the department Myxomycota with the subdivision Myxomycotina, which unites the class Phycomycetes (phycomycetes) - aquatic fungi.

Phycomycetes class includes about 700 species of fungi. Phycomycetes have a well-developed unicellular non-septate (having no partitions) multinuclear mycelium. Mushrooms of this class are subdivided into the order of Mucorales Mucorales, the Mysogasaeae family, which unites the main genera Mucor, Rhizopus and Thamnidium, which are the causative agents of defects (spoilage) of dairy and other products.

Higher mushrooms include spore-forming yeasts, as well as fungi characterized by multicellular mycelium. Cells have one nucleus, many have two or more.

The sub-kingdom of higher fungi includes the department true (real) fungi (Eumycota), the subdivision true fungi (Eumycotina), which combines three classes: Ascomycetes - ascomycetes, or marsupial fungi, Basidiomycetes - basidiomycetes, or basidiomycetes, and the class of imperfect fungi (Deuteromycetes - deuteromycetes, fungi imperfecti).

Ascomycete class (from lat. ascus- bag + Greek. myces- mushroom) unites more than 30 thousand species. characteristic feature for the whole class is sexual sporulation and the presence in cells (bags) usually 8 endogenous spores (ascospores), sometimes 4 or 2. The class Ascomycetes includes the order Endomycetales, which includes the family Endomycetaceae, which includes non-mycelial unicellular spore-forming fungi called yeasts, in particular yeasts of the genus Saccharomyces. These yeasts are used in the manufacture of bread, wine, beer, alcohol, etc. Spore-forming yeasts also include lactic yeasts of the species Saccharomyces lactis and S. casei.

Class Basidiomycetes (from the Greek. basidion- small base, foundation + myces- mushroom) combines more than 20 thousand species of fungi with a developed septate mycelium. The main organ of sporulation in them are club-like structures - basidia (homolog of asca). From the basidiospores, the primary (haploid) mycelium develops, which, as a result of the fusion of hyphae, gives the secondary (diploid) mycelium with the fusion of the nuclei, that is, sexual reproduction begins.

The class of imperfect fungi includes more than 25 thousand fungi that do not have sexual sporulation. They have a developed multicellular mycelium. Non-spore-forming yeasts are also included in this class.

The absence of a sexual cycle in imperfect fungi forces researchers to classify fungi into orders, families, and genera only on the basis of morphology. Therefore, several classifications have been proposed for mushrooms of this class.

According to the nature of conidial sporulation, the class of deuteromycetes is divided into several orders, among which highest value have hyphomycelial (Hyphomycetales) fungi (from the Greek. hype- fabric + myces- mushroom) and Protoascales (protoasco fungi). The order of hyphomycelial fungi includes the Moniliaceae family, which includes the mold genera Aspergillus, Penicillium, Cladosporium, Alternaria, Catenularia, as well as the milk mold Geotrichum (Oidium, Endomyces) lactis, which are frequent causative agents of defects in dairy products.