How to cultivate Pholiota nameko for high yield? The latest cultivation technique tutorial

Pholiota nameko, also known as nameko mushroom or the booted scalycap, is called nameko in Japan. In botanical classification it belongs to the kingdom Fungi, subphylum Basidiomycotina, class Basidiomycetes, order Agaricales, family Cortinariaceae, genus Pholiota. It is a rare variety, native to Japan. Since the mid-1970s it began to be cultivated in southern Liaoning province, and the current main production areas are northern Hebei, Liaoning, Heilongjiang and other places.

Biological characteristics

1. Nutrition. Pholiota nameko is a wood-rotting fungus, and in nature it mostly grows on broadleaf trees, especially on the stumps and fallen logs of Fagaceae. In artificial cultivation of Pholiota nameko, sawdust, straw, rice bran, wheat bran and other agricultural by-products rich in lignin, cellulose, hemicellulose and protein are used as the culture material. The demand of Pholiota nameko for auxin does not require additional supplementation in the commonly used formulas based on rice bran and wheat bran.

2. Temperature. The mycelium of Pholiota nameko can grow at any temperature between 5°C and 32°C, with the optimum temperature being 22°C to 25°C. The fruiting body can grow between 5°C and 18°C; above 20°C, the fruiting body cap is thin, the stipe is slender, and the cap opens early; below 5°C, growth is slow and basically does not occur.

3. Light. Cultivation of Pholiota nameko does not require direct light, but there must be sufficient scattered light. The mycelium can grow normally in a dark environment, but light has an effect of inducing fruiting in physiologically mature Pholiota nameko mycelium. During the fruiting stage, a certain amount of scattered light should be provided. If the light is too dim, the cap color is pale, the stipe is slender, the quality is poor, and yield will also be affected.

4. Humidity. The water content of the mycelium culture material is preferably 60% to 65%. During the fruiting body formation stage, the water content of the culture material is best at 75% to 80%, and the relative air humidity requirement is 85% to 95%.

5. Air. Pholiota nameko is also an aerobic fungus, and its oxygen demand is related to respiratory intensity. In early spring, at the beginning of inoculation, the temperature is low, the mycelium grows slowly, and a small amount of oxygen can meet the need; as the temperature rises, mycelial metabolism accelerates, respiration increases, and mycelial mass increases, so attention must be paid to ventilation of the mushroom house and air exchange inside and outside the material bags. During the fruiting stage, the metabolism of the fruiting body is very vigorous, and fresh air is even more needed. If the carbon dioxide concentration in the environment exceeds 1%, the fruiting body cap will be small, the stipe slender, and the cap will open early.

6. pH. The pH of the culture material directly affects the activity of cellular enzymes. The mycelial growth of Pholiota nameko requires a pH value of 5 to 6. The culture material made from sawdust, wheat bran and rice bran generally has a pH of 6 to 7, but after heating and sterilization the pH value will decrease, so there is no need to adjust the pH value again.

High-yield cultivation techniques

1. Cultivation season

Pholiota nameko is a low-temperature, temperature-variable fruiting type fungus. In northern China, spring planting and autumn fruiting are generally adopted. Semi-cooked material cultivation is suitable, and it is best to choose the early spring season when the temperature is below 8°C. The optimal sowing period is mid-February to mid-March.

2. Selecting excellent spawn

① Variety selection. According to differences in fruiting temperature, Pholiota nameko is divided into very early-maturing types (optimal fruiting temperature 7°C to 20°C), early-maturing types (5°C-15°C), medium-maturing types (7°C-12°C), and late-maturing types (5°C-10°C). Producers should choose excellent varieties according to local climate, cultivation method and purpose. At present, the main varieties cultivated in the main production areas mainly include Zaofeng 112, c3-1 and others.

② Spawn selection. When selecting spawn, it is required that it is not degenerated and not mixed. From its appearance, the mycelium should be white and fluffy, growing densely, uniformly and robustly; the spawn age should be 50-60 days, not aged, not shriveled, and without water accumulation; when selecting spawn, different varieties should be used in combination and not a single variety alone, to prevent fruiting from being too concentrated and affecting product sales.

3. Construction of the fruiting shed for Pholiota nameko

A good cultivation site is the basic condition for the normal growth and development of Pholiota nameko. Under the current production level and economic conditions in rural areas, generally idle houses are used in a simple way, and sheds or rooms are used as mushroom houses. There are also places such as air-raid shelters and mountain caves used for cultivating Pholiota nameko, and most adopt dual use of one site, that is, it is both a mycelium culture room and a fruiting room for the growth and development of fruiting bodies.

At present, standardized production generally uses louver-type fruiting sheds, with a shed height of 3.5 m. The cultivation racks in the shed can be built in layers with wooden poles or bamboo poles. Generally, the rack height is 1.7 m to 1.8 m, the width is 0.6 m, the bottom layer is 0.2 m from the ground, and the spacing between layers is 0.3 m to 0.4 m. Seven layers are suitable, with a 0.8 m walkway left in the middle. A structure with cement as uprights and four No. 8 iron wires pulled as crossbars can also be used.

4. Commonly used formulas

① Sawdust 77%, wheat bran (or rice bran) 20%, gypsum 2%, superphosphate 1%, pH 6.0-6.5, water content 60%-65%.

② Currently promoted formula: sawdust 84%, wheat bran or rice bran 12%, corn flour 2.5%, gypsum 1%, lime 0.5%, pH 6.0-6.5, water content 60%-65%.

5. Mixing materials

Weigh the culture material according to the proportion, mix evenly, and add water according to the dryness or wetness of the raw materials so that the water content reaches 60%-65%, then pile and let stand for 30 minutes.

6. Sterilization

① Use the loose-material sterilization steam type (inflatable boiler) layered material-spreading sterilization method. First lay a layer of gunny bags on the steamer tray to prevent material leakage. After the steam rises, spread the culture material evenly on the steamer tray to a thickness of about 6 cm to 8 cm (it must not be patted or pressed with hands or shovels). When the steam rises strongly, use a shovel to spread the material in layers, spread the material evenly, and suppress the steam. Load layer by layer in this way, filling to 8 fen full, that is, the material surface is loaded to 20 cm from the upper opening. Cover and press firmly, apply strong fire until reaching 100°C, then maintain for 2 hours, then let stand for 30 to 40 minutes, and then remove from the pot while hot. Sterilization must be thorough. Each pot is suitable for sterilizing 200-500 trays (note: when coarse sawdust is used as the main material, the sterilization time should be extended).

② Bagging into trays. First place the mold on the tray, soak the pre-cut film in an 800-fold dilution of Boli solution or place it in a 0.1% potassium permanganate solution for 10 minutes, then lay it on the mold. Fill the sterilized culture material into the tray while hot. The temperature of the culture material must not be lower than 80°C. Press the culture material in the spawn tray tightly, compact it, and wrap it well.

7. Inoculation

① Disinfection of the inoculation room and preparations. First, disinfect the inoculation room well. Use 5 g to 8 g of disinfectant box per cubic meter for key disinfection. Operators should make preparations before inoculation according to operating requirements, spray culture trays and all carrying and inoculation tools with 5% Lysol; close doors and windows so that the indoor air is still.

② Inoculation method. When the material temperature drops to about 25°C, inoculation can be carried out according to aseptic operation requirements. Use 200 g or 250 g of spawn per standard tray. Remove the old skin and primordia, break the spawn into pieces the size of apricot kernels, open the film, sprinkle the spawn on the material surface, press appropriately with a sterilized pressing board, fold the film in half and roll both ends upward tightly to prevent water evaporation. Production practice has proved that appropriately increasing the inoculation amount allows the mycelium to grow rapidly and can prevent the early occurrence of contaminating microorganisms.

8. Mycelium growth management

① Management during the mycelial germination and colonization period. Inoculation of Pholiota nameko in the north is generally arranged to be completed from mid-February to mid-March. At this time, the average daily temperature is about -6°C to 5°C, which has not reached the minimum temperature above 5°C required for mycelial growth. At this time, artificial heating is needed. If trays are stacked outdoors for mycelial growth, the mushroom stacks should be surrounded with corn stalks or straw at night. To promote mycelial colonization, measure the material temperature once every three or four days. When the temperature of the spawn block is above 12°C, the spawn trays should be placed on racks individually.

② Management during the mycelial expansion and surface-covering period. The colonized mycelium gradually turns white and extends to all sides. As the temperature increases, the mycelium grows faster and grows into the material, but as the temperature rises, contaminating microorganisms will also spread, causing contamination. At this stage, the focus should be on preventing contamination. Spawn trays not yet placed on racks should be arranged in a “pin” shape, with stack height below 8 layers. The temperature in the shed should be controlled at 8°C to 12°C. It is required to turn the trays and reverse the stacks once every five to seven days, and increase ventilation.

③ Management during the period when the mycelium has fully grown. Entering mid-April, the temperature rises, and the mycelium has grown over the entire tray. At this time, mycelial respiration strengthens, oxygen demand increases, and heat is released, so the temperature needs to be controlled at about 18°C, and ventilation should also be increased.

④ Summering management. When the hot season arrives in July and August, Pholiota nameko has generally formed a yellow-brown waxy layer, the spawn block is elastic, and its resistance to adverse environments is enhanced. However, if the temperature exceeds 30°C, the mycelium in the spawn block will die due to high temperature and insufficient oxygen supply. Therefore, at this stage, shading should be strengthened, and ventilation should be carried out day and night. In addition to opening skylights or installing ventilation tubes on the shed roof, double-layer shade nets or water-spray cooling facilities should also be installed. In addition, insect-proof nets should be installed at all ventilation openings to prevent adult insects from flying in or larvae from causing damage. When necessary, low-toxicity, residue-free biological pesticides can be sprayed. For example: spray 20% deltamethrin or cypermethrin, etc.

9. Management during the fruiting period

In mid-August, when the temperature stabilizes at about 18°C, Pholiota nameko has reached physiological maturity, and the trays can be opened for fruiting management.

① Scoring the mycelium. If the mycelial film on the spawn block is too thick, it is not conducive to fruiting, so a bamboo knife or iron nail should be used to score lines on the surface of the spawn block, cutting vertical and horizontal lines into a grid about 2 cm wide. Score through the mycelial film, with moderate depth, generally 1 cm deep is sufficient; scoring too deep may easily cause the spawn block to break. Then place it flat or upright on the rack, spray water, and adjust the room temperature to about 15°C to promote fruiting body formation.

② Temperature management. Pholiota nameko belongs to the low-temperature type, and the fruiting body grows more suitably under conditions of 10-15°C. Above 20°C, fruiting body formation is slow, the mushroom cap is small, the stipe is slender, the flesh is thin, and the cap opens easily. The fruiting body has strong resistance to low temperature and can also grow at about 5°C, but not vigorously. Under variable temperature conditions, the fruiting body grows extremely well, with more mushrooms produced, larger fruiting bodies, thicker flesh, good quality, and robustness without contaminating microorganisms. After September, in late autumn, the natural temperature difference is large, so the natural temperature difference should be fully utilized, management should be strengthened, and more mushrooms should be promoted. At night, when the temperature is low, the temperature of the fruiting room should not be lower than 10°C; at noon, when the temperature is high, attention should be paid to ventilation so that the temperature of the fruiting room is not higher than 20°C.

③ Humidity management. Water is one of the important conditions for high yield of Pholiota nameko. To ensure the water needed for the growth and development of the fruiting bodies of Pholiota nameko, water should be sprayed appropriately to increase the water content of the spawn block (about 70%) and the air humidity (about 90%). Water should be sprayed at least twice a day. The amount of water applied should be determined according to the indoor humidity and the growth of the fruiting bodies. Air humidity should be maintained between 85% and 95%. In dry weather with excessive airflow, the number of water sprays can be appropriately increased. The more fruiting bodies occur, the more vigorous the growth of the mushrooms and the greater the metabolic capacity, the more the amount of water applied needs to be increased. Points to note when spraying water: when spraying water on the spawn trays, use a sprayer to spray finely and frequently, so that water slowly seeps into the spawn block through the surface scores; do not spray forcefully or with a large amount of water. When spraying, keep the nozzle of the sprayer higher to prevent water from striking the fruiting bodies. In winter, if heating equipment is used in the fruiting room, do not spray water before heating; spray water 2 hours after the room temperature rises.

④ Ventilation management. During the fruiting period, mycelial respiration increases, and oxygen demand increases significantly. Therefore, the indoor air should be kept fresh. During ventilation, pay attention to changes in temperature and humidity. If the natural temperature is relatively high during the fruiting period and indoor ventilation is poor, it will cause no fruiting or an increase in deformed mushrooms. In addition, during seasons with higher temperatures, ventilation openings and exhaust holes must be opened day and night during fruiting to allow air convection and ensure sufficient oxygen indoors for the needs of the fruiting bodies.

⑤ Light management. The fruiting bodies of Pholiota nameko need scattered light during growth. The spawn blocks should not be placed too densely, and the room should not be too dark. If there is not enough scattered light, the color of the mushrooms will be pale and the stipes slender.

10. Management during the harvest period

Pholiota nameko should be harvested before the cap opens. Harvesting after the cap opens not only lowers the commercial quality of Pholiota nameko, but also, because the spores fall on the spawn tray after the cap opens, it will cause infection of the spawn tray. The harvest standard is determined according to the requirements of the purchaser. After harvesting the first flush of mushrooms, water should be stopped for 2 to 3 days to allow the mycelium on the mushroom tray to recover and accumulate nutrients, so that the water content of the mushroom tray reaches 70% and the air humidity in the shed reaches 85%. Strengthen ventilation and increase the day-night temperature difference to promote the formation of the second flush of mushrooms.