Who can tell me in detail about the strains used to cultivate shiitake mushrooms?

The key to the success of artificially cultivated edible fungi is strain. Only excellent strains can achieve high quality and high yield. Mushroom strains are divided into mother species (the original species is called the first-level species), the original species (the mother species is bred and is called the second-level species) and the cultivated species (the mother species is bred for production and cultivation, is called the third-level species) according to the source and production purpose. level species).

The cost of using mother seeds directly for cultivation is high. Producing mother seeds by yourself requires equipment and technology, which is too costly. Breeding original species and cultivated species yourself can reduce equipment investment, reduce costs, and obtain high-quality bacterial sources.

1 Original seed production

1.1 Preparation of culture medium

Select fresh, dry, mildew-free hardwood fine wood chips 55%, wheat bran 20%, cottonseed 20 shells, 3 cornmeal, 2 gypsum, material to water ratio 1:1.1, stir evenly, and put into 15 cm × 30 cm polyethylene original seed bag. Bagging with appropriate tightness, loose bagging with less material, and tight bagging that is airtight will affect quality and output.

1.2 Normal pressure steam sterilization

If the conditions are met, use a pressure cooker for sterilization (maintain at 0.015 MPa pressure for 2 hours). Generally, normal pressure and high temperature are used for sterilization. A small amount can be steamed in a large pot in rural areas. The temperature is required to rise quickly. When it reaches 100°C, it should be kept for 12 hours and simmered for 8 hours. If the effect is not good, you can use the intermittent sterilization method. Steam the bag in a steamer at 100°C three times for 2 hours each time, with a 24-hour interval between each time. Although it is time-consuming and troublesome, the effect is good. .

Factory production, using normal pressure steam hood sterilization. Choose two layers of high-temperature resistant and long-lasting plastic film and one layer of checkered cloth to form a large sealed space. Place 4,500 bags in the space at a time. Use heavy objects to tighten the outside of the cover to avoid air leakage. Place an exhaust pipe at the bottom of the steam hood, and cover the pipe with bricks to avoid dead ends caused by uneven ventilation. The exhaust pipe is connected to the boiler. When the temperature rises to 100°C, steam for 24 hours and simmer for 12 hours. The sterilized bags are then transported to a sterilized room ready for inoculation.

1.3 Inoculation

Choose a well-ventilated room, put the inoculation hook, shovel, and test tube rack into the inoculation box, and use Bejis or clotrimazole aerosol to inoculate the room and inoculation box Disinfect and sterilize. After the smoke has dissipated naturally for 12 hours, open the windows for ventilation in preparation for vaccination. Before inoculation, wipe your hands and inoculation tools with a towel or cotton ball soaked in 75% alcohol, light the alcohol lamp so that the flame is surrounded by a sterile area, and burn the inoculation shovel, hook and the mouth of the test tube of the mother seed through the flame, and immediately remove the test tube after cooling Cut the medium-sized mother seed into three pieces, untie the original seed material bag, put in a piece of bacteria, tie the bag immediately, do it quickly, put a label on it after the inoculation is completed, and move the bag that has received the seed to the sterilizer. A poisonous place.

1.4 Mother culture

Place the inoculated mother bacteria sticks in the culture room (incubator), keep the room temperature at 23 ℃ ~ 26 ℃, pay attention to ventilation, check frequently, and eliminate contamination After 25 to 30 days, the mycelium has grown all over the bag, which is the original seed.

2 Production of cultivated seeds

The ingredient bag and sterilization are basically the same as the production of original seeds, with a size of 15 cm × 55 cm.

2.1 Inoculation

If the amount of cultivated species is large, the vaccination site should also be large, and vaccination should be carried out by hanging a vaccination tent in a greenhouse. Generally, the greenhouse is 90 meters long and contains 40,000 to 45,000 bags, divided into 10 groups. A longevity film is hung in the middle to separate them, forming two large spaces (convenient for disinfection and sterilization). Create a tight small space in the large space, the size is based on releasing each group of bags (4 000 ~ 4 500). Use long-lived film to construct a small, flowing and closed room (with an exit). Each set of bags is fumigated and sterilized by BJS inside and outside the vaccination tent. One box is placed inside the vaccination tent, and 4 boxes are evenly placed outside the tent. Sterilize 5 hours before inoculation, ventilate 3 hours later, and start inoculation 2 hours later.

The vaccinators are divided into groups of 6. One person wipes the material bag with a towel soaked in 75% alcohol, 2 people use an inoculation cone to evenly poke 3 bacterial holes on the material bag, and 2 people sterilize ( Before inoculation, scrub the original seed bag with 0.2 potassium permanganate or 1 gram of amoxicillin aqueous solution. Use a razor blade to cut the original seed bag, break the bacteria into conical pieces, the size is suitable for stuffing into the bacterial pores, and plug them tightly. Be sure not to crush them. One person will move the inoculated bags to both sides of the tent and stack them into stacks. After the inoculation is completed, each two stacks should be tightly covered with 0.08-thick film to prepare for the growth of bacteria. The above-mentioned 6 people all put on sterilized work clothes, masks, disposable gloves and sterilized vaccination tools before vaccination, and divided their labors and cooperated in streamlined operations.

2.2 Cultivation of cultivars

During the cultivation of cultivars, Trichoderma is the most susceptible fungus, and the affected colonies appear light green, yellow-green, dark green, and blue-green. or green, with rapid onset and serious harm, so prevention is the priority. If the conditions are met, it can be cultured at a variable temperature. The suitable temperature for the germination of Lentinus edodes mycelium is 25 ℃. At 16 ℃, the mycelium growth rate exceeds that of Trichoderma mycelium. Above 25 ℃, Trichoderma mycelium grows faster than that of Lentinus edodes. Therefore, after the mushrooms are inoculated, the temperature should be controlled at 16°C. When the mycelium fills the bag, the temperature will gradually rise to 25°C, so that miscellaneous bacteria have no opportunity to take advantage of it and avoid harm. If the temperature change cannot be controlled, chemicals can be used to prevent and control it. If mildew occurs locally in the bacterial bag, promptly inject or apply 1 Grammazin or 0.5 Duofengnong or 0.1 formaldehyde solution. You can also use 10% bleaching powder solution for local application. Frequently spray 0.1 Green Thunder Cleaner or 0.1 Formaldehyde on the space inside the shed to purify the environment. At the same time, pay attention to the temperature of the shed and stacks at any time. The appropriate temperature is around 25°C. If the temperature exceeds 30°C, immediately turn over the stacks to cool down and ventilate them. If you cultivate them with all your heart, white mycelium will appear in 25 to 30 days, with a cotton-like shape, uniform and vigorous growth, and cloth. If the bag is full, it is a cultivated species.