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There are many ways to get mushroom mycelium, and many of them have been verified to the smallest detail over the years of painstaking experiments. But there are also methods for preparing mycelium, which are still imperfect and require additional research. This is what mycologists-practitioners do in the laboratory and amateur mushroom growers who grow mycelium with their own hands at home.
In nature, mushrooms mainly reproduce by spores, but this process can also be carried out using pieces of mushroom tissue, which mushroom growers have long established using wild-growing mycelium as planting material.
How to make mycelium at home is described in detail on this page.
How people used to grow mycelium themselves
Previously, in order to grow certain types of mushrooms, for example, champignons, people looked for dunghills and took mycelium from there. If the weather was unfavorable, and there was no mycelium in the landfills, then it was propagated in special exploratory greenhouses. For this, manure soils (substrate) were prepared and mycelium was planted there, without filling it with earth, so that fruiting did not occur. After waiting for the almost complete germination of the mycelium in the substrate, the mushroom growers took out the mycelium and used it as planting material. Such a slightly dried nutrient medium could be preserved for a long time.
In Our Country, champignon planting material was obtained in a similar way back in the 30s. XNUMXth century However, when growing mycelium using this method, the yields were poor, the mycelium quickly degenerated, and during planting, alien microorganisms were often introduced, which prevented the normal development of the fungus and reduced fruiting, and therefore scientists continued to look for new ways of cultivation.
At the end of the XIX century. in France, they achieved the production of a sterile champignon mushroom culture grown in a special nutrient medium from spores. When preparing mycelium in clean conditions, the potential of the mycelium increased significantly, it quickly took root, grew intensively in a nutrient medium and bore fruit much earlier than when using “wild” hyphae.
Since the mid 20s. 30th century laboratories functioned in many mushroom-producing countries, they not only knew how to prepare mycelium, but also how to achieve excellent fruiting. In the 1932s. in the USSR, in addition to obtaining mycelium on sterilized compost, other nutrient media were also actively sought. In XNUMX, a method for cultivating mycelium on wheat grain was patented. At the moment, most mushroom growers around the world are engaged in the cultivation of grain mycelium.
Cons of growing grain mycelium
As practice shows, in order to obtain mycelium, grains of millet, barley, oats, wheat, corn, rye and other cereals are most often used. When breeding oyster mushrooms and other crops that develop in nature on wood, the sowing mycelium is prepared on grain, sunflower husks, grape pomace, sawdust, etc.
Depending on the type of nutrient medium on which the mycelium grows, there are grain, substrate, liquid mycelium, etc.
All these types of mycelium are shown in the photo:
Liquid mycelium is practically not common, substrate mycelium is used a little more often, but grain is mainly used. Due to the fact that the grain mycelium, due to the nutrients of the grain, provides accelerated growth of the mycelium, it is used in industrial mushroom growing.
However, the preparation of such mycelium in industrial or domestic conditions has its drawbacks. First of all, these are increased requirements for the quality of grain sterilization. If this procedure was unsuccessful, then mold will appear, preventing the normal development of the mycelium, which will necessarily affect the volume of the crop.
The short shelf life of grain mycelium (2-3 months) is also a significant disadvantage. In addition, it must be stored in the refrigerator at a temperature of + 2-5 ° C, as this will slow down the development of the mycelium. If the temperature is higher, this will lead to the fact that the growth of the mycelium will continue, as a result of which it will quickly consume food and die.
By the appearance of the mycelium, it is impossible to determine the date of its manufacture. The only thing that can be recommended in this case is to be vigilant when purchasing it on the side, because the storage conditions could not be observed. The novice mushroom grower will find out that the mycelium is of poor quality many months later, when it will be in vain to wait for the harvest.
The disadvantage can also be attributed to the fact that the mycelium, accustomed to grain, will not “want” to move to wood.
With substrate mycelium, the situation is different, and its only disadvantage is considered to be a slightly slower growth, but there are more pluses: sterility, the ability to store at room temperature for a year.
Amateur mushroom growers tend to prefer substrate mycelium when cultivating mushrooms on wooden pieces, since germination speed does not matter here. This process continues for several months due to the high density of the tree.
It is important to know that mycelium of any kind dies if it is heated above 30°C.
Entire organizations are engaged in the production of mycelium, where optimal conditions for its cultivation are created. Some get mycelium at home in the hope of earning some money. Its quality does not always meet the necessary requirements, but, in fairness, it is worth noting that sometimes there are very good specialists.
Mushrooms can of course be propagated by spores, but mycelium propagation is much more preferable for a novice mushroom grower, as it gives a better chance of success.
Further, the process of obtaining mycelium is considered in detail, since it is sometimes simply necessary to grow it yourself, for example, if for some reason the mycelium obtained in natural conditions (for example, pieces of wood or soil penetrated by mycelium) is not enough.
The key points for preparing mushroom mycelium with your own hands are as follows. First, a sterile fragment of fungal tissue is removed and transferred to a nutrient medium (this occurs in several stages, which will be discussed below). Then, several samples are formed from the main culture, and care should be taken especially to prevent infection of the culture. Next, create an environment and conditions that are most conducive to the fruiting of the fungus.
In the process, the culture undergoes the following changes: sterile culture on agar medium, sterile culture on grain (grain mycelium) and, finally, fruiting in a pasteurized nutrient medium.
The word “sterility” can be a bit intimidating for beginners, but it’s absolutely essential to protect your mushroom culture from the many sources of contamination that are present in the environment, no matter how clean the environment is. It is very important to prevent them from getting into the cultivated culture, because otherwise there will be a “struggle” for the nutrient medium, and only the mushroom culture should use it.
With a certain accuracy and practice in performing fairly simple techniques, the sterilization process can be carried out by anyone.
The following describes how to prepare mushroom mycelium agar.
How to get agar for mycelium at home
Before preparing mycelium at home, you should prepare an agar nutrient medium. Agar made from seaweed, together with additional components, is often used for the primary cultivation and subsequent isolation of a fungal culture.
Specialists add a variety of nutrients to agar, for example, minerals, antibiotics, etc. The value of the agar medium lies also in the fact that microorganisms that cause infection can be easily detected on the surface of the medium and thus it is possible to eliminate them on early stages of cultivation.
As practice shows, you can make mycelium yourself in different types of agar media. The most commonly used are potato and malto-dextrin agar. You can make them yourself or purchase ready-made mixtures of industrial production in the store.
When purchasing agar in a store, you will have to spend a little more money, but the additional expenses are offset by ease of use, and if you have finances and lack of free time, ready-made mixtures will be the best choice.
If you are used to doing everything with your own hands, then, according to experts, potato agar for mushroom mycelium at home can be prepared in two ways. Both methods differ little from each other. In addition, after familiarizing yourself with them, each mushroom grower may well come up with his own way.
In any case, in order to make mushroom mycelium the way the right technology suggests, you need to prepare: measuring cups, cotton bandage, aluminum foil, pressure cooker, test tubes with screw caps for autoclaving (can be found in medical equipment stores), a small funnel for filling test tubes , 2 bottles with a volume of 1 l, flasks with a narrow neck.
Next, you will learn how to make potato mycelium agar in the first way.
The first way to prepare potato agar
The estimated yield of the substance is 1 liter.
Ingredients: 300 g potatoes, 20 g agar (available from appropriate medical lab supplies, health food stores, or Asian food markets), 10 g dextrose or some other sugar, 2 g brewer’s yeast (can be dispensed with) ).
The process of work.
Step 1. Before making agar for the mycelium of the rough, you need to boil the potatoes with 1 liter of water for 1 hour. Then remove the potatoes, leaving only the broth.
Step 2. Broth, agar, sugar and yeast (if you use them) mix thoroughly, for example, using a whisk for whipping, you can not beat this mixture.
Step 3. Pour the resulting mixture into bottles or flasks by half or three quarters of their volume.
Close the necks with cotton swabs and wrap with aluminum foil. Pour water into the pressure cooker so that its layer from the bottom of the dish is 150 mm, and install a grid on which to place bottles or flasks. Cover the dish with a lid and snap the latches.
Step 4. Put the steamer on the fire and wait until the steam comes out. After ventilation for a few minutes (depending on the specific model and in accordance with the instructions), close the valve. The bottles are boiled at 121°C (1 atm.) for 15 minutes. At the same time, it is necessary to ensure that the temperature does not exceed this level, because in this case, caramelization of the medium will occur, which will completely ruin it.
Step 5. After 15 minutes, turn off the stove and leave the dishes to cool (about 45 minutes). Then, without wasting time, take free test tubes, remove the caps and place the containers on a tripod or in clean cans, and then place them on a surface previously cleaned of dust and dirt.
Step 6. Once the culture medium bottles have cooled, remove them from the pressure cooker using a towel or kitchen mittens. Mixing lightly, remove the foil and swabs, using a funnel, pour the contents into the test tubes by about one third.
Step 7. Close the test tubes with caps, but less tightly than before, place them in a pressure cooker, pouring out excess water if necessary. Having reached a temperature of 121 ° C, leave the dishes on fire for 30 minutes, then leave it to slowly cool down again until the pressure reaches a normal level.
Step 8. Take out the tubes and screw the caps tighter. Fix the tubes in an inclined position. As a result, the surface of the agar medium should be at an angle with respect to the flask, thus creating as much area as possible for the subsequent development of mycelium (such tubes are sometimes called “slant agar”).
As the medium cools, it becomes more and more jelly-like in consistency and eventually hardens to such an extent that the tubes can be placed vertically and the agar medium will remain in its original position.
This video details the preparation of mycelium agar:
The tubes can be used immediately or after weeks or even months. In the latter case, they must be placed in the refrigerator, and before use, make sure that there are no signs of mold or bacteria contamination on the medium.
The next section of the article is devoted to how to get potato mycelium agar at home in a different way.
How to make agar for mycelium at home in a different way
The estimated yield of the substance is 1 liter.
Ingredients:
- 284 g potatoes,
- 21,3 g (3/4 oz) agar
- 8 g dextrose (you can use table sugar instead).
The process of work.
Step 1. To make agar for mycelium with your own hands, you need to wash the potatoes and cut them into small pieces, leaving the skins, and then boil them in 0,5 liters of water until fully cooked. Remove potatoes and their scraps. Pour 1 liter of water into an iron or glass dish and add dextrose (sugar), decoction and agar to it.
Step 2. Dissolve agar. To do this, put the resulting agar mixture in a bowl covered with aluminum foil into a pressure cooker. Heat the pressure cooker to 121°C (1 atm) and leave. After 20 minutes, the agar will completely dissolve. Then turn off the stove and let the pressure cooker cool down slowly.
Step 3. Using kitchen mittens or towels, pour the mixture with dissolved agar into test tubes (or small bottles) to a third of the volume. Place the test tubes on a rack or in cans. Pour the remains of agar into a bottle, close it with a cotton or padding tampon and sterilize later, along with the rest of the test tubes.
Caps of test tubes or lids should not be tightly closed. In this case, the pressure will equalize during sterilization. If cotton or padding tampons are used for closing, you can not care about pressure equalization, however, additionally, the test tubes should be covered with aluminum foil, otherwise the condensate of the cooling pressure cooker will fall on the stoppers.
Step 4. Sterilize agar, for which test tubes (bottles) with it should be placed in a pressure cooker and kept at a temperature of 121 °C (1 atm.) for 25 minutes, not including the time spent to achieve the required pressure. Then turn off the stove and leave the dishes to cool slowly. A rapid decrease in pressure should not be allowed, because this can cause the agar in the tubes to boil, splash out through the swabs and stopper caps, which is likely to lead to infection.
Step 5. At the final stage, the mixture in the test tubes acquires an inclined position. To do this, wipe the surface on which the test tubes will be placed with a 10% bleach solution containing chlorine. There should be no drafts in the room.
With the help of kitchen mittens or a towel from the pressure cooker, take out hot test tubes and place them on the table in an inclined position, leaning the container with one end against some object. Before that, it is advisable to choose the correct angle of inclination using some foreign objects (bars, a stack of magazines, etc.)
When the agar begins to solidify, turning into jelly, close the caps (plugs) in the test tubes more tightly.
Store potato agar in test tubes in a cool, dust-free place.
Watch a video on how to make agar for mycelium with your own hands:
The final section of the article is devoted to how to properly grow mushroom mycelium.
How to cook mushroom mycelium at home
Before growing mycelium at home, prepare: a scalpel (a sharp knife with a thin blade), a spirit lamp (a propane torch with a canister, a lighter or matches), iron cans or racks for test tubes with slant agar and prepared test tubes, a scalpel holder or knife, microporous bandage (standard bandage is fine), spray bottle with a mixture of 1 part bleach with chlorine and 9 parts water (optional), fresh clean mushroom fruiting body (if you are a beginner, it is best to use oyster mushrooms).
The process of work.
Step 1. Before growing mycelium, you need to prepare a stable surface (table, counter) by washing it with warm soapy water and wiping it dry. To provide additional disinfection, treat the surface with an aerosol with a 10% bleach solution, wipe thoroughly with a clean rag or paper towel. Close the windows to prevent air circulation as much as possible. It is better to carry out work in the morning hours, when there is little dust in the air.
Step 2. To grow mycelium at home, you need to organize the workspace: lay out tools and materials within reach and in a convenient order, ready for work.
Take agar tubes and place them in iron cans or on racks. Turn on the light and carefully sterilize the blade of the knife (scalpel) in the fire, put it on a stand, for example, made of wire. The stand is needed so that the knife blade can always be near the fire while the tool is not in use.
Step 3. Take a fresh clean mushroom. Although its outer surface may well contain many pathogens and molds, there are usually no organisms in the inner tissue that can cause infection, of course, if there is not too much water in the fungus.
It is impossible to break off a part of the fungus, because the blade infects the inside of the fungus with bacteria from the outer surface. Put the mushroom on the table with a dirty surface (a clean one should not come into contact with the table).
The bottom line is that you need to form a clean open surface, and subsequently take a small piece of mushroom tissue from it, which is placed in a test tube.
Step 4. In order to grow mycelium yourself, arrange the tools and materials in such a way that the test tube is opened as little as possible before filling with mushroom tissue. To reduce the chance of infection, the test tube (or stopper, cap) should not be placed on the work surface, which is quite difficult, so it makes sense to practice with an empty test tube in advance.
Step 5. The further sequence is largely determined by whether the right-handed or left-handed person performs this work, the actions of the right-handed person are described below.
The thumb of the left hand is down, while the others are horizontal. Place the test tube between the middle and ring fingers. In this case, the ring finger is on top, the middle finger is on the bottom of the flask, and the cork (lid) is directed away from the hand. It is not necessary to tilt the test tube, only a horizontal position is required here, otherwise the particles flying in the air will have a greater chance of penetrating into the neck of the container. The orientation of the tube is such that the bevelled surface of the agar is directed upwards. It is on it that mushroom tissue will be planted.
Step 6. Carefully remove the stopper (lid) from the test tube and take the latter in the indicated way.
Using the free forefinger and thumb of the left hand, take a piece of mushroom with a clean surface. With your right hand, quickly take the scalpel in such a way as if it were a pencil or a pen. Using the tip of a blade, carefully detach a small piece of a triangular mushroom from a clean mushroom tissue and, immediately, place it in a flask on the edge of the neck, if necessary, shaking it off the tip of the scalpel with tapping movements. Put the scalpel back and quickly close the tube with a stopper.
Step 7. Tap the tube lightly on your hand to move the piece of fungus onto the agar surface. Place the tube in another tin designed for storing inoculated tubes.
If the recommendations are followed exactly, there is a good chance that the transplanted mushroom culture was clean.
A similar sequence of actions is performed with other flasks and mushroom material. It is important to prepare several test tubes from one mushroom, because no matter how carefully and cleanly the work is done, infections often occur.
After the mushroom material has been introduced into the test tube (this process is called inoculation), the scalpel must be sterilized again on fire.
Having finished with the test tubes, you need to close the stopper as tightly as possible and wrap the place with microporous tape, which will not prevent the fungus from “breathing” and at the same time will not allow bacteria to enter the test tube through the neck.
It is advisable to place stickers on each flask or make inscriptions with a marker indicating the date and information about the contents.
Ready test tubes are stored in a dark and cool place at an optimum temperature of 13-21 °C. After a certain time (several days or a week), the mushroom tissue will become overgrown with fluff, which indicates the beginning of mycelium development. After a few more weeks, the mycelium will flood the entire surface of the agar.
In the presence of mold, which is easily recognizable by green or black spores, or bacterial contamination (as a rule, it looks like a colored glossy substance), the contents of the test tube should be discarded immediately and washed with hot soapy water together with the cork. If possible, infected test tubes are uncorked in another room where there are no healthy cultures.
Details on how to grow mycelium are described in this video:
