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The branch of biology that studies the features of the structure, nutrition and development of fungi is called mycology. This science has a long history and is conventionally divided into three periods (old, new and recent). The earliest scientific works on the structure and life of mushrooms that have survived to this day date back to the middle of 150 BC. NS. For obvious reasons, these data were revised many times in the course of further study, and a lot of information was disputed.

A description of the structure of mushrooms, as well as the main features of their development and nutrition, are presented in detail in this article.

General characteristics of the structure of the mycelium of the fungus

All mushrooms have a vegetative body called mycelium, i.e. mycelium. The external structure of the mycelium of fungi resembles a bundle of thin twisting filaments, called "hyphae". Typically, the mycelium of common edible fungi develops in soil or decaying wood, and the mycelium of parasites grows in the tissues of the host plant. Fungal fruiting bodies with spores grow on the mycelium, with which the fungi multiply. However, there are a large number of fungi, in particular parasitic ones, without fruit bodies. The peculiarity of the structure of such mushrooms is that their spores grow directly on the mycelium, on special spore carriers.

Young mycelium of oyster mushroom, champignon and other cultivated mushrooms is represented by thin white filaments that look like a white, gray-white or white-blue plaque on the substrate, reminiscent of a cobweb.

The structure of the mycelium of the fungus is shown in this diagram:

In the process of maturation, the shade of the mycelium becomes creamy and small strands of intertwined threads appear on it. If, during the development of the acquired mycelium of fungi (in a glass jar or bag) on ​​the surface of the substrate (grain or compost can act as it), the strands are approximately 25-30% (set by eye), this means that the planting material was of high quality. The smaller the strands and the lighter the mycelium, the younger it is and usually the more productive it is. Such a mycelium will take root without any problems and will develop in the substrate in greenhouses and hotbeds.

Speaking about the structure of the mushroom, it is important to note that the growth and development rate of the oyster mushroom mycelium is much higher than that of the mushroom mycelium. In oyster mushrooms, the planting material after a short time becomes yellowish and with a large number of strands.

This figure shows the structure of the oyster mushroom:

The creamy shade of the oyster mushroom mycelium does not mean low quality at all. However, if the filaments and strands are brown in color with brown liquid drops on their surface or on a container with mycelium, then this is a sign that the mycelium has overgrown, aged or has come under the influence of unfavorable factors (for example, it was frozen or overheated). In this case, you should not count on a good survival of the planting material and on the harvest.

These signs will help determine how the mycelium grows in the substrate. The formation of strands in the general structure of the fungus indicates the readiness of the mycelium for fruiting.

If there are spots or blooms of pink, yellow, green, black flowers in a container with mycelium or in a seeded substrate (in a garden bed, in a box, in a plastic bag), it is safe to say that the substrate has become moldy, in other words, it has become covered with microscopic fungi, a kind of " competitors ”of cultivated mushrooms and oyster mushrooms.

If the mycelium is infected, then it is not suitable for planting. When the substrate is infected after planting myceliums in it, the infected areas are carefully removed and replaced with a fresh substrate.

Next, you will find out what are the structural features of the fungus spores.

The structure of the fruiting body of the fungus: the shape and characteristics of the spores

Although the most famous is the shape of the structure of the fruiting body of the fungus in the form of a cap on a leg, it is far from the only one and is only one of many examples of natural diversity.

In nature, you can often see fruiting bodies similar to a hoof. These are, for example, in tinder fungi that grow on trees. The coral form is characteristic of horned mushrooms. In marsupials, the shape of the fruiting body is similar to a bowl or glass. The shapes of the fruit bodies are very diverse and unusual, and the color is so rich that sometimes the mushrooms are quite difficult to describe.

To get a better idea of ​​the structure of the mushroom, see these figures and diagrams:

Fruit bodies contain spores, with the help of which fungi that are inside and on the surface of these bodies multiply, on plates, tubes, spines (cap mushrooms) or in special chambers (raincoats).

The shape of the spores in the structure of the fungus is oval or spherical. Their sizes range from 0.003 mm to 0.02 mm. If you look at the structure of the spores of the fungus under a microscope, you will see droplets of oil, which are a reserve nutrient designed to facilitate the germination of spores into the mycelium.

Here you can see a photo of the structure of the fruiting body of the fungus:

The color of the spores is different, ranging from white and ocher-brown to purple and black. The color is established according to the plates of an adult mushroom. Russules are characterized by white plates and spores, in champignons they are brown-violet, and in the process of maturation and an increase in the number of plates, their color changes from pale pink to dark purple.

Thanks to such a fairly effective way of reproduction, like scattering billions of spores, mushrooms have been successfully solving the problem of procreation for more than one million years. As the famous biologist and geneticist, Professor AS Serebrovsky, figuratively put it in his "Biological walks": "After all, every autumn, scarlet heads of fly agarics appear here and there from under the ground and, shouting with their scarlet color:" Hey, come in, don't touch me, I'm poisonous! ”- scatter millions of their insignificant spores in the quiet autumn air. And who knows how many millennia these mushrooms have been preserving their fly agaric genus with the help of spores, since they so radically solved the greatest of life's problems ... "

In fact, the amount of spores thrown into the air by the fungus is enormous. For example, a small dung beetle with a cap only 2-6 cm in diameter produces 100-106 spores, while a rather large mushroom with a 6-15 cm cap produces 5200-106 spores. If we imagine that all this volume of spores sprouted and fertile bodies appeared, then a colony of new fungi would occupy an area of ​​124 km2.

Compared to the number of spores produced by flat tinder fungus with a diameter of 25-30 cm, these figures fade, since it reaches 30 billion, and in the fungi of the raincoat family, the number of spores is difficult to imagine and it is not for nothing that these fungi are among the most prolific organisms on earth.

A mushroom called Langermannia giant in size often approaches the size of a watermelon and produces up to 7.5 trillion spores. Even in a nightmare, one cannot imagine what would have happened if all of them had sprouted. Emerging mushrooms would cover an area larger than Japan. Let your imagination run wild and imagine what it would be like if the spores of this second generation of mushrooms sprouted. Fruiting bodies would be 300 times the volume of the Earth.

Fortunately, nature has taken care of the mushroom overpopulation. This fungus is extremely rare and therefore a small number of its spores find the conditions in which they could survive and germinate.

Spores fly in the air anywhere in the world. In some places there are fewer of them, for example, in the region of the poles or over the ocean, but there is no corner where they do not exist at all.This factor should be taken into account and the peculiarities of the structure of the body of the fungus should be taken into account, especially when breeding oyster mushrooms indoors. When the mushrooms begin to bear fruit, picking and caring for them (watering, cleaning the room) must be carried out in a respirator or at least in a gauze bandage covering the mouth and nose, as its spores can cause allergies in sensitive people.

You can not be afraid of such a threat if you grow champignons, ringlets, winter mushrooms, summer mushrooms, since their plates are covered with a thin film, which is called a private veil, until the fruiting body is fully ripe. When the mushroom ripens, the veil breaks, and only a trace on the leg in the form of a ring remains, and the spores are thrown into the air. However, with this development of events, the disputes are still less, and they are not so dangerous in the sense of causing an allergic reaction. In addition, the harvest of such mushrooms is harvested before the film breaks completely (while the commercial quality of the product is significantly higher).

As shown in the picture of the structure of oyster mushrooms, they do not have a private cover:

Because of this, spores in oyster mushrooms are formed immediately after the formation of the plates and are thrown into the air throughout the entire growth of the fruiting body, starting with the appearance of the plates and ending with full ripening and harvesting (this usually occurs 5-6 days after the rudiment of the fruiting body will form).

It turns out that the spores of this fungus are constantly present in the air. In this regard, advice: 15-30 minutes before harvesting, you should slightly humidify the air in the room with a sprayer (water should not get on the mushrooms). Along with droplets of liquid, spores will settle on the ground.

Now that you have familiarized yourself with the characteristics of the structure of mushrooms, it's time to learn about the basic conditions for their development.

Basic conditions for the development of fungi

From the moment the primordia is formed and until full maturation, the growth of the fruiting body usually takes no more than 10-14 days, of course, under favorable conditions: normal temperature and humidity of the soil and air.

If we recall other types of crops grown in the country, then for strawberries from the moment of flowering to full ripening in central Russia, it takes about 1.5 months, for early varieties of apples - about 2 months, for winter varieties this time reaches 4 months.

In two weeks, cap mushrooms are fully developed, while raincoats can grow up to 50 cm in diameter or more. There are several reasons for such a rapid development cycle of fungi.

On the one hand, in favorable weather, it can be explained by the fact that the mycelium under the ground already contains mostly formed fruiting bodies, the so-called primordia, which contain full-fledged parts of the future fruiting body: a leg, a cap, and plates.

At this point in its life, the mushroom intensively absorbs soil moisture to such an extent that the water content in the fruiting body reaches 90-95%. As a result, the pressure of the cell contents on their membrane (turgor) increases, causing an increase in the elasticity of the fungal tissue. Under the influence of this pressure, all parts of the fruiting body of the fungus begin to stretch.

We can say that the impetus for the growth of primordia is given by humidity and temperature. Having received data that the humidity has reached a sufficient level, and the temperature meets the conditions of vital activity, the mushrooms quickly stretch in length and open their caps. Further, the emergence and maturation of spores occurs at a rapid pace.

However, the presence of sufficient humidity, for example, after rain, does not guarantee that many mushrooms will grow. As it turned out, in warm, humid weather, intensive growth is observed only in the mycelium (it is he who produces the pleasant mushroom smell so familiar to many).

The development of fruiting bodies in a significant number of fungi occurs at a much lower temperature.This is due to the fact that mushrooms need a temperature difference in addition to humidity for growth. For example, the most favorable conditions for the development of champignon mushrooms is the temperature at the level of + 24-25 ° С, while the development of the fruiting body begins at + 15-18 ° С.

At the beginning of autumn, autumn honey reigns supreme in the forests, which loves the cold and reacts very noticeably to any fluctuations in temperature. Its temperature "corridor" is + 8-13 ° С. If this temperature is in August, then honey honey begins to bear fruit in summer. As soon as the temperature rises to + 15 ° C or more, the mushrooms stop bearing fruit and disappear.

The mycelium of the velvety-footed flammulina begins to germinate at a temperature of 20 ° C, while the fungus itself appears on average at a temperature of 5-10 ° C, however, a lower temperature is suitable for it, up to minus.

Such features of the growth and development of fungi should be taken into account when cultivating them in the open field.

Mushrooms have the characteristic of rhythmic fruiting throughout the growing season. This is most clearly manifested in cap mushrooms, which bear fruit in layers or waves. In this regard, among mushroom pickers there is an expression: "The first layer of mushrooms has gone" or "The first layer of mushrooms has gone down." This wave is not too abundant, for example, in white boletus, it falls at the end of July. At the same time, the mowing of grain occurs, therefore mushrooms are also called "spikelets".

During this period, mushrooms are found in elevated places, where oaks and birches grow. In August, the second layer, the late summer layer, ripens, and in late summer - early autumn, the time for the autumn layer comes. Mushrooms that grow in autumn are called deciduous. If we consider the north of Russia, tundra and forest-tundra, then there is only an autumn layer - the rest merge into one, August. A similar phenomenon is typical for high-mountain forests.

The richest harvests under favorable weather conditions fall on the second or third layers (end of August - September).

The fact that mushrooms appear in waves is explained by the specifics of the development of the mycelium, when cap mushrooms begin to bear fruit instead of a period of vegetative growth throughout the season. This time varies greatly for different types of mushrooms and is determined by weather conditions.

So, in a champignon grown in a greenhouse, where an optimally favorable environment is formed, the growth of the mycelium lasts 10-12 days, after which active fruiting continues for 5-7 days, followed by the growth of mycelium for 10 days. Then the cycle is repeated again.

A similar rhythm is found in other cultivated mushrooms: winter mushroom, oyster mushroom, ringlet, and this cannot but affect the technology of their cultivation and the specifics of caring for them.

The most obvious cyclicality is observed when growing mushrooms indoors under controlled conditions. In open ground, weather conditions have a decisive influence, due to which the fruiting layers can move.

Next, you will find out what type of nutrition the mushrooms have and how this process occurs.

How the process of feeding mushrooms occurs: characteristic types and methods

The role of fungi in the general food chain of the plant kingdom can hardly be overestimated, since they decompose plant residues and thus actively participate in the constant circulation of substances in nature.

The processes of decomposition of complex organic substances, such as fiber and lignin, are the most important problems in biology and soil science. These substances are the main constituent elements of plant litter and wood. By their decay, they determine the cycle of carbonaceous compounds.

It has been established that 50-100 billion tons of organic substances are formed on our planet every year, a huge part of which are plant compounds.Every year in the taiga region the litter level varies from 2 to 7 tons per hectare, in deciduous forests this number reaches 5-13 tons per hectare, and in meadows - 5-9.5 tons per hectare.

The main work on the decomposition of dead plants is carried out by fungi, which nature has endowed with the ability to actively destroy cellulose. This feature can be explained by the fact that fungi have an unusual way of feeding, referring to heterotrophic organisms, in other words, to organisms that do not have an independent ability to convert inorganic substances into organic ones.

In the process of feeding, mushrooms have to assimilate ready-made organic elements produced by other organisms. This is precisely the main and most important difference between fungi and green plants, which are called autotrophs, i.e. independently forming organic matter with the help of solar energy.

By the type of nutrition, mushrooms can be divided into saprotrophs, which live by feeding on dead organic matter, and parasites, which use living organisms to obtain organic matter.

The first type of mushrooms is quite diverse and very widespread. These include both very large fungi - macromycetes, and microscopic - micromycetes. The main habitat of these fungi is soil, which contains almost countless spores and mycelium. Saprotrophic fungi growing in forest turf are no less common.

Many species of fungi, called xylotrophs, have chosen wood as their place of residence. These can be parasites (autumn honey fungus) and saprotrophs (common tinder fungus, summer honey fungus, etc.). From this, by the way, we can conclude why it is not worth planting winter honey in the garden, in the open field. Despite its weakness, it does not cease to be a parasite, capable of infecting trees on the site in a short time, especially if they are weakened, for example, by unfavorable wintering. Summer honey fungus, just like oyster mushroom, is completely saprotrophic, therefore it cannot harm living trees, growing only on dead wood, so you can safely transfer the substrate with mycelium from the room to the garden under trees and shrubs.

Autumn honey fungus, popular among mushroom pickers, is a real parasite that seriously damages the root system of trees and shrubs, causing root rot. If you do not take any preventive measures, then the honey fungus in the garden can only destroy the garden for several years.

After washing the mushrooms, water should not be poured out in the garden, unless it is in a compost heap. The fact is that it contains many spores of the parasite and, having penetrated into the soil, they are able to get from its surface to the vulnerable places of trees, than cause their disease. An additional danger of the autumn honeydew is that under certain conditions the fungus can be a saprotroph and live on dead wood until there is a chance to get on a living tree.

Autumn honeydew can also be found on the soil next to trees. The filaments of the mycelium of this parasite are closely intertwined into the so-called rhizomorphs (thick black-brown strands), which are capable of spreading underground from tree to tree, entwining their roots. As a result, honey fungus infects them in a large area of ​​the forest. At the same time, the fruiting bodies of the parasite are formed on the strands developing underground. Due to the fact that it is located at a distance from the trees, it seems that honey fungus is growing on the soil, but its strands in any case have a connection with the root system or the trunk of the tree.

When breeding autumn mushrooms, it is necessary to take into account how these mushrooms are fed: in the process of vital activity, spores and parts of the mycelium accumulate, and after exceeding a certain threshold, they can cause infection of trees, and no precautions will help here.

As for mushrooms such as champignon, oyster mushroom, ringlet, they are saprotrophs and do not pose a threat when grown outdoors.

This also explains why it is extremely difficult in artificial conditions to grow valuable forest mushrooms (porcini mushroom, boletus, camelina, butter dish, etc.). The mycelium of most cap fungi binds to the root system of plants, in particular trees, resulting in the formation of a fungus root, i.e. mycorrhiza. Therefore, these mushrooms are called "mycorrhizal".

Mycorrhiza is one of the types of symbiosis, often found in many fungi and until recently remained a mystery to scientists. Most woody and herbaceous plants can create symbiosis with fungi, and the mycelium located in the ground is responsible for such a connection. It grows together with the roots and forms the conditions necessary for the growth of green plants, at the same time receiving ready-made food for itself and the fruit body.

The mycelium envelops the root of a tree or shrub in a dense cover, mainly from the outside, but partially penetrates inside. Free branches of mycelium (hyphae) branch off from the cover and, diverging in different directions in the ground, replace root hairs.

Due to the special nature of nutrition, with the help of hyphae, the fungus sucks out water, mineral salts and other soluble organic substances, mostly nitrogenous, from the soil. A certain amount of such substances enters the root, and the rest goes to the fungus itself for the development of the mycelium and fruit bodies. In addition, the root provides carbohydrate nutrition to the mushroom.

For a long time, scientists could not explain the reason why the mycelium of most forest cap fungi does not develop if there are no trees nearby. Only in the 70s. XIX century. it turned out that mushrooms do not just have a habit of settling near trees, for them this neighborhood is extremely important. A scientifically confirmed fact is reflected in the names of many mushrooms - boletus, podilanik, podvishhen, boletus, etc.

The mycelium of mycorous fungi penetrates the forest soil in the root zone of trees. For such mushrooms, symbiosis is vital, because if the mycelium can still develop without it, but the fruiting body is already unlikely.

Previously, the characteristic way of feeding mushrooms and mycorrhiza was not given much importance, which is why there were numerous unsuccessful attempts to grow edible forest fruit bodies in artificial conditions, mainly boletus, which is the most valuable of this variety. The porcini mushroom can enter into a symbiotic relationship with almost 50 tree species. Most often in Russian forests there is a symbiosis with pine, spruce, birch, beech, oak, hornbeam. In this case, the type of tree species with which the fungus forms mycorrhiza affects its shape and color of the cap and leg. In total, about 18 forms of porcini mushroom are isolated. The color of the caps ranges from dark bronze to almost black in oak and beech forests.

Brown birch forms mycorrhiza with certain types of birch, including dwarf, which is found in the tundra. There you can even find brown birch trees, which are much larger in size than the birches themselves.

There are fungi that only associate with a certain tree species. In particular, the larch oiler creates a symbiosis exclusively with larch, which is reflected in its name.

For the trees themselves, this connection with mushrooms is of considerable importance. Judging by the practice of planting forest belts, we can say that without mycorrhiza trees grow poorly, become weak and are subject to various diseases.

Mycorrhizal symbiosis is a very complex process. This relationship between fungi and green plants is usually determined by environmental conditions. When the plants lack nutrition, they "eat" the partially processed branches of the mycelium, the fungus, in turn, experiencing "hunger", begins to eat the contents of the root cells, in other words, resorts to parasitism.

The mechanism of symbiotic relationships is quite subtle and very sensitive to external conditions. Probably, it is based on parasitism common for fungi on the roots of green plants, which in the course of long evolution has turned into a mutually beneficial symbiosis. The earliest known cases of mycorrhiza of woody species with fungi were found in upper carbonaceous sediments approximately 300 million years old.

Despite the difficulties of growing forest mycorrhizal mushrooms, it still makes sense to try to breed them in summer cottages. Whether it will succeed or not depends on various factors, so it is impossible to guarantee success here.