Mushroom cultivation method Mushroom bagging and sterilization

How to better cultivate shiitake mushrooms? Today, I will explain to you the cultivation methods of shiitake mushrooms in detail:

1. Cultivation Methods of Shiitake Mushrooms

There are two methods for cultivating shiitake mushrooms: log cultivation and substitute material cultivation. The mushrooms produced by log cultivation have high commodity quality and a high input-output ratio of 1:7-10, but it requires a large amount of wood and is only suitable for development in forest areas. The input-output ratio of substitute material cultivation is only 1:2, but the production cycle of substitute material cultivation is short and the biological efficiency is high. Moreover, it can utilize various crop straws and forest waste, which is beneficial to the protection of the ecological environment and can be widely developed in urban and rural areas. Substitute material cultivation requires a large one-time input and is relatively costly. This chapter focuses on substitute material cultivation technology.

1. Arrangement of sowing period and selection of strains

Shiitake mushroom production mostly uses shade sheds or fruit forests as fruiting sites, which are greatly affected by climatic conditions and are highly seasonal. The sowing period of shiitake mushrooms in various places should be determined according to local climatic conditions and variety characteristics. In our area, tube making is generally carried out from September to October (slightly earlier in mountainous areas), and fruiting occurs from December to January. Too early tube making is prone to infection with bacteria and low yield due to high temperature and high humidity. Too late will affect color change and shorten the fruiting period.

2. Preparation of cultivation materials

Sawdust is the main raw material for bag-grown mushrooms. Except for pine, fir and camphor wood, most hardwoods and branches can be used as raw materials for mushroom production after being crushed.

(1) The ingredients of several cultivation materials are calculated based on 100 kg and can be increased or decreased depending on the scale of production.

① 78% sawdust, 20% bran (fine rice bran), 1% gypsum, 1% sugar, and 0.3% urea. The water content of the material is 55% to 60%.

② Sawdust 78%, bran 16%, cornmeal 2%, sugar 1.2%, gypsum 2%~2.5%, urea 0.3%, superphosphate 0.5%. The moisture content of the material is 55%~60%.

③ Sawdust 78%, bran 18%, gypsum 2%, superphosphate 0.5%, magnesium sulfate 0.2%, urea 0.3%, brown sugar 1%. The water content of the material is 55% to 60%.

Preparation of the above three kinds of planting materials: first mix the gypsum and bran evenly, then mix them evenly with the sawdust, dissolve the sugar and urea in water, sprinkle them evenly on the materials, turn them over and sprinkle them with a shovel, and use a bamboo broom to repeatedly sweep the surface of the materials evenly.

④ Cottonseed husk 50%, sawdust 32%, bran 15%, gypsum 1%, superphosphate 0.5%, urea 0.5%, sugar 1%. The moisture content of the material is about 60%.

⑤ Bean straw 46%, sawdust 32%, bran 20%, gypsum 1%, sugar 1%. The moisture content of the feed is 60%.

⑥ Sawdust 36%, cottonseed husk 26%, corn cob 20%, bran 15%, gypsum 1%, superphosphate 0.5%, urea 0.5%, sugar 1%. The moisture content of the material is 60%.

Preparation of the above three kinds of cultivation materials: weigh various ingredients according to quantity, first add water to cottonseed husk, bean straw, corn cob and other water-absorbent materials at a material-water ratio of 1:14-1.5, mix well, and make the materials absorb water thoroughly; dry-mix gypsum, superphosphate, bran and sawdust evenly, and then mix evenly with cottonseed husk, bean straw or corn cob that has been mixed with water; dissolve sugar and urea in water and mix them into the materials, adjust the water content of the materials at the same time, and stir the materials evenly with a shovel and bamboo broom. No dry particles of materials can be left.

(2) Issues that should be noted when mixing ingredients Sawdust refers to sawdust from broad-leaved trees, that is, hardwood sawdust. Old sawdust is better than fresh sawdust. Before mixing ingredients, the sawdust should be sieved to remove coarse sawdust to prevent puncturing the plastic bag. The coarseness should be moderate. Too fine sawdust affects the ventilation in the bag. 10% to 30% cottonseed husk should be added to the sawdust cultivation material to increase production; but if the proportion of cottonseed husk and corn cob in the cultivation material is too large, the fungus column is easy to break when the bag is removed and the mushrooms are produced. Too much bran and urea should not be added to the cultivation material, otherwise it is easy to cause the mycelium to grow too long and it is difficult to change color and produce mushrooms. Bran and rice bran should be fresh, not lumpy, and not infested with insects or mold. Bean straw should be powdered into coarse bran, and corn cob powder should be powdered into bean-sized particles.

The water content of shiitake mushroom cultivation materials should be slightly lower than that of oyster mushroom cultivation materials, and is generally controlled at 55% to 60% in production. A slightly lower water content is beneficial to control the contamination of bacteria, but after the first wave of mushrooms, the mushroom column should be replenished with water in time, otherwise it will affect the fruiting of mushrooms. Due to the different dryness and wetness of the raw materials, different hardness and coarseness, the material-water ratio during mixing is also different. Generally, the material-water ratio is 1:0.9 to 1.3, which is a large difference. Therefore, when each batch of materials is used for mixing for the first time in production, the water content should be measured after the materials are mixed to determine an appropriate material-water ratio.

①Hand test method: Take a handful of the mixed cultivation material and hold it in your hand. When there is no water between your fingers, stretch out your palm and the material will form a ball.

② Drying method. Weigh 500g of the mixed material accurately, spread it thinly on an enamel tray, dry it at a temperature of 105, and weigh the dry material until the weight of the dry material no longer decreases. The moisture content of the material (%) = wet material weight - dry material weight wet material weight × 100 When mixing the ingredients, adding 0.1% carbendazim (referring to the active ingredient) of the dry material with the water will help prevent contamination by miscellaneous bacteria.

3. Bagging and sterilization of mushrooms

Bag-grown shiitake mushrooms are the most representative cultivation method for shiitake mushrooms. Although the specific operations vary from place to place, the principle is the same. (1) Specifications of plastic tube materials In fact, most shiitake mushroom bag cultivation uses plastic tubes with openings at both ends, including polypropylene plastic tubes with a wall thickness of 0.04-0.05 cm and low-pressure polyethylene plastic tubes with a thickness of 0.05-0.06 cm. Polypropylene tubes can be sterilized at high pressure or normal pressure, but in winter when the temperature is low, polypropylene tubes become brittle and easy to break; low-pressure polyethylene tubes are suitable for normal pressure sterilization. The specifications of plastic tubes used in production are also varied, with plastic tubes with a width of 15 cm and a tube length of 55-57 cm.

(2) Before bagging and sterilizing, tie up one end of the plastic tube. There are two ways to tie the mouth: one is to tie two circles of nylon rope around one end of the plastic tube that is inoculated with side holes, and then fold the mouth of the tube over and tie it tightly to prevent air leakage from the mouth of the tube; the other is that some producers use 17 cm × 35 cm short plastic tubes for loading materials, with both ends open for inoculation. One end of the plastic tube must also be tied up tightly, but it is not necessary to fold it over and then tie it. The plastic tube with one end tied up is called a plastic bag. Before bagging, check for leaks. The way to check is to blow up the plastic bag, put it in water, and see if there are any bubbles coming out. Leaking plastic bags must never be used. It is best to use a bagging machine to bag in groups of 5. One person adds material to the hopper; two people take turns to put the plastic bag on the discharge barrel, gently hold the bag mouth with one hand, and push it with the other hand.

Hold the bottom of the bag and try to pack it tight, the tighter the better. The other two people will organize the material bag and tie it up. Be sure to tie the bag tightly. The tying method is the same as the other end of the bag. When packing by hand, shake the plastic bag while loading the material, and use a thick wooden stick to compact the material. After packing, tie the bag tightly. The bag filled with material is called a material bag. In high temperature seasons, it is necessary to concentrate manpower to pack quickly. Generally, it is required that the time from the beginning of bagging to the sterilization of the pot should not exceed 6 hours, otherwise the material will become sour and smelly. When the material bag is put into the pot, there should be a certain gap or the "#" shape should be stacked in the sterilization pot, so that air circulation is convenient and dead corners are not easy to appear during sterilization. When using high-pressure steam sterilization, the material bag must be a polypropylene plastic bag. As the temperature rises during heating and sterilization, the cold air in the pot must be released. When the pressure gauge points to 1.5 kg/cm2, maintain the pressure for 2 hours and stop heating. Cool down naturally, let the pressure gauge pointer slowly fall back to 0, open the air valve first, and then open the pot to take it out. When using a normal pressure steam sterilizer, the fire should be strong and fierce when starting to heat up. The time from lighting the fire to the temperature in the pot reaching 100℃ should not exceed 4 hours, otherwise the material will become sour and smelly.

When the temperature reaches 100℃, it should be maintained at medium heat for 8 to 10 hours without cooling down in the middle. Finally, it should be heated up for a while, then simmered overnight before serving. Before serving, disinfect the cooling room or inoculation room.

The plastic baskets used for taking out the food should also be sprayed with 2% Lysol or 75% alcohol for disinfection. The hot bags just out of the pot should be transported to a sterilized cooling room or inoculation room for cooling. Inoculation can only be done when the bag temperature drops below 30°C.

4. Mushroom inoculation and cultivation management

(1) Inoculation of shiitake mushroom bags is usually done by punching holes on the side, which requires several people to do at the same time. Therefore, it is more convenient to operate in an inoculation room and a plastic inoculation tent. The specific method is to first disinfect the inoculation room, then transport the freshly cooked bags to the inoculation room and stack them up in rows and layers. For each layer of bags, spray 0.2% carbendazim on the bags with a handheld sprayer. After all the bags are arranged, prepare the inoculation strains, adhesive tape, a conical wooden stick with a diameter of 1.5 to 2 cm for punching holes, 75% alcohol cotton balls, cotton yarn, inoculation tools, etc. Close the doors and windows, turn on the ozone disinfector, and disinfect for 40 minutes; open the door 15 minutes after shutting down, and the inoculation personnel quickly enter the inoculation room, close the door of the outer room, wear work clothes, spray 75% alcohol to disinfect the space, and then enter the inner room. Inoculation is carried out according to aseptic operation (same as the strain part). For side hole inoculation, a 55 cm long plastic tube is generally used as a material bag, with 5 holes, 3 holes on one side and 2 holes on the other side. Three people form a group. The first person puts the conical head of the wooden stick used for hole in an enamel cup filled with 75% alcohol. The alcohol should be immersed in the tip of the wooden stick for 2 cm. Then move a material bag to be inoculated to the table, wipe the upward side of the material bag with 75% alcohol cotton gauze with one hand to disinfect it, and use the wooden stick to punch 3 holes on the side of the disinfected material bag with the other hand. One hole is located in the middle of the material bag, and the other two holes are close to the two ends of the material bag. The second person opens the bottle cap of the bacteria, rotates the bottle mouth on the alcohol lamp and burns it for a circle, and the long-handled tweezers are also burned on the flame of the alcohol lamp for sterilization; after cooling, scrape the surface of the bacteria in the bottle mouth, and then put the bacteria into a plastic tube disinfected with 75% alcohol or 2% Lysol; after disinfecting both hands with alcohol cotton balls, directly break the bacteria into small jujube-sized bacteria blocks and quickly fill them into the hole. The bacteria should fill the inoculation hole and be slightly higher than the hole mouth. Note that the second person's hands should be disinfected with alcohol frequently, and the hands should not touch any place except holding the bacteria. The third person uses 3.5 cm × 3.5 cm square adhesive paper to seal the inoculated hole tightly, and turns the bag 180 degrees, with the side that receives the seeds facing down. The first person wipes the upward side of the bag with alcohol cotton gauze, punches two holes on the bag at equal distances, and then puts the tip of the wooden stick for punching holes into alcohol for disinfection, and then moves the second bag. The second person fills the two inoculation holes of the first bag with bacteria, and the third person seals the holes with adhesive paper, and moves the first bag (called a fungus bag) to the side with the inoculation holes facing the side. The inoculated fungus bags can be placed in the culture room for cultivation. Use a 35 cm long plastic tube as a bag, and you can make holes on the side for inoculation. Generally, 3 holes are made, 2 on one side, or both ends can be opened for inoculation.

The success rate of inoculation in an inoculation box is often higher than that in an inoculation room because the box has a small space, good sealing, and thorough disinfection. However, a single-person inoculation box can only be operated by one person and is only suitable for inoculation at the two openings of a short bag. If it is a side hole inoculation, it is best to use a two-person inoculation box, which is operated by two people. One person is responsible for punching the hole and sealing the hole with adhesive paper, and the other person transfers the strain into the hole according to the sterile procedure.

(2) Bag culture refers to the management from inoculation to the time when the mushroom mycelium fills the bag and reaches physiological maturity. The bag culture period is usually called the spawning period. The spawning can be done indoors (greenhouses) or in shaded sheds. The spawning site should be clean and free of pollution sources. It should be far away from pig farms, chicken farms, garbage dumps and other places where bacteria breed. It should be dry, ventilated and shaded. Disinfection, sterilization and pest control should be carried out before spawning in the bags, and lime should be sprinkled on the ground. The spawning period of shiitake mushrooms in summer is in the high temperature season. The temperature is often higher than the optimum temperature for mycelium growth (24-27℃), so the focus of management during the spawning period is to prevent high temperature from burning the mushrooms. For the newly inoculated bags, three bags are stacked in a triangular row, with the inoculation holes facing the side. The number of layers of spawn in each row depends on the temperature. If the temperature is high, fewer layers can be stacked. There should be walkways between rows to facilitate ventilation and cooling and to check the growth of the bags. The temperature of the spawning site should be controlled below 28℃. Do not turn over the bags for the first 7 to 10 days. Turn over the bags for the first time on the 13th to 15th day. At this time, the mycelium of each inoculation hole grows radially. When the diameter is 8 to 10 cm, the growth volume increases and the respiration intensity increases. Attention should be paid to ventilation and cooling. While turning over the bags, use a 1 mm diameter steel needle to pierce 3 to 4 micro holes in the middle of the mycelium growth part of each inoculation point, about 2 cm away from the front of mycelium growth; or peel off half of the adhesive paper sealing the inoculation hole, fold inward to create a small hole for ventilation, and pick out the bags contaminated by bacteria. At this time, due to the high heat generated by mycelium growth, ventilation and cooling should be strengthened. It is best to control the temperature of the spawning site below 25℃. Mycelium growth is weak when it exceeds 32℃, mycelium will stop growing at 35℃, and mycelium can burn to death at 38℃. There are many ways to cool down, which can be mastered flexibly. For example, reduce the number of layers of bags and expand the spacing between bags to facilitate heat dissipation and cooling; for fungi in greenhouses and shade sheds, thicken the covering during the day and remove the covering at night; for fungi in indoor and greenhouses, take advantage of the low outside temperature at night to strengthen ventilation and cooling, and install exhaust fans if conditions permit; if the temperature is too high, spray cold water to cool down, but pay attention to strengthening the wind after spraying water, and do not cause the environment to be too humid to prevent contamination by bacteria. Turn the bag over again after about 30 days of cultivation. While turning the bag over, use a steel wire needle to pierce the second micropore at the mycelium, 2 cm away from the front of the mycelium growth. Poke a circle of 4 to 5 micropores at the mycelium growth site of each inoculation point, and the hole depth is about 2 cm. In order to prevent the bag from being contaminated by bacteria due to bag turning and piercing, the bag must be packed tightly when packing. The tighter the bag is packed, the lower the contamination of bacteria. For all closed fungi sites, such as rooms and greenhouses, space disinfection should be carried out before turning the bag over and piercing, which can effectively reduce bacteria contamination. During the fungus period, special attention should be paid to insect prevention and control.

Due to the different sizes of the bags and the number of inoculation points, it usually takes 45 to 60 mycelia to fill the bag. At this time, continue to cultivate until the mycelia around the inner wall of the bag expands, with wrinkles and raised tumors, and gradually increase to occupy 2/3 of the entire bag surface. When the tumors in the bag are elastic and soft when pinched by hand, and there is a little brown around the inoculation hole, it indicates that the mycelia of shiitake mushrooms are physiologically mature and can be brought to the mushroom farm for color change and fruiting.

(3) Color change management When the mycelium of shiitake mushrooms enters the physiological maturity stage, the white mycelium on the surface gradually turns into a layer of brown mycelium film under certain conditions, which is called mycelium color change. The depth of color change and the thickness of mycelium film directly affect the occurrence and development of shiitake mushroom primordia, which has a great impact on the yield and quality of shiitake mushrooms. It is the most important link in the management of shiitake mushroom production.

There are many methods for color change, and the most commonly used method is the bag-taking color change method. The time of bag-taking should be accurately grasped, that is, the bag-taking should be done when the mycelium reaches physiological maturity. If the bag-taking is too early, the color change is not easy, and if it is too late, the mycelium will age and yellow water will often appear, which is easy to cause contamination by miscellaneous bacteria, or the mycelium film will thicken, making it difficult for the primordium of shiitake mushrooms to differentiate. The climate when bag-taking should be 15-25℃, preferably 20℃. Before bag-taking, the floor of the mushroom greenhouse should be made into a 30-40 cm deep and 100 cm wide bed, and a layer of furnace ash or sand should be laid on the bottom of the bed. The bags to be bagged and changed color should be transported to the greenhouse, the bags should be cut with a blade, the plastic bags should be taken off, and the columnar mushroom blocks should be arranged in rows at a spacing of 5-8 cm in the row. If the long mushroom columns are unstable, bamboo poles can be used to build a horizontal frame on the row, and the mushroom columns should be leaned against the bamboo poles at an angle of 70-80 degrees. After removing the bags, the mushroom columns should be protected from the sun and wind. At this time, the relative humidity of the air in the greenhouse should be controlled at 75% to 80%. The mushroom columns with yellow water can be washed with clean water. The mushroom columns should be removed from the bags and arranged quickly. When a bed is full, the top of the bed should be arched with bamboo strips immediately, and plastic film should be covered to maintain moisture and heat preservation around. After all the mushroom columns are arranged, the temperature of the greenhouse should be controlled at 17 to 20℃, not exceeding 25℃. If the temperature is high, cold water can be sprayed into the space of the greenhouse to cool it down. When the temperature is high during the day, add more shading materials, remove the shading materials at night, and increase ventilation to cool down. The light should be darker, and try not to uncover the cover film on the bed for the first 3 to 5 days. At this time, the relative humidity in the bed should be 85% to 90%, and there will be condensed water droplets on the plastic film, so that the mycelium will continue to grow in a warm, humid and stable environment. It should be noted that if the temperature is high and the humidity is too high during this period, the cover film of the bed should be uncovered for ventilation for 20 minutes every day when the temperature is low in the morning and evening. When uncovering the film of the bed, do not ventilate the greenhouse at the same time, and stagger the ventilation time of the two. When the mushroom column is 5 to 7 days old and the surface of the mushroom column is covered with thick white fluffy aerial hyphae, the number of times of film uncovering and ventilation should be increased, 2 to 3 times a day, each time for 20 to 30 minutes, to increase oxygen and light (scattered light), increase the dry and wet difference on the surface of the mushroom column, limit the growth of hyphae, and promote its color change. When the color changes after 7 to 8 days, the ventilation can be increased, and each time for 1 hour. Combined with ventilation, lightly spray water on the surface of the mushroom column 1 to 2 times a day, and let it dry for 1 hour after spraying water before covering the film. Spray water continuously for 2 days, and the color change is completed in 10 to 12 days. In the growth practice, due to different sowing seasons, the climatic conditions of the color change site, especially the temperature conditions, are different, and the speed of color change is not the same. The specific operation should be flexibly mastered according to the growth of hyphae on the surface of the mushroom column.