How to prevent miscellaneous bacteria infection and mildew rot in spring cultivation of white fungus?

    White fungus cultivated in spring is mostly harmed by green mold, with some contamination by Rhizopus and Mucor, while Neurospora is rare. Green mold, Mucor and Rhizopus often occur beside the inoculation holes of the fungus bags, or 9—10 days after inoculation when the fungal circles of two holes meet, appearing at the front end of the mycelium, or on the bag wall. Green mold also occurs on the fruiting bodies, causing the ear pieces to rot. Neurospora mostly occurs at the gaps tied at the bag mouth. The main reasons are incomplete sterilization of the material bags, lax aseptic operation, broken holes in the bag film, impure spawn carrying contamination, environmental pollution, etc.

Production of white fungus bags

    To avoid miscellaneous bacteria contamination of white fungus, do well in several aspects:

    1. Purify the mushroom house environment: often clean the environment and spread lime powder for disinfection; before cultivation in the house, strictly disinfect and sterilize to eliminate pollution sources.

    2. Carefully select raw and auxiliary materials: cottonseed hulls and wheat bran are required to be free of caking, mildew and deterioration, and placed under the blazing sun for sterilization; the quality of cultivation bags is tested beforehand.

    3. Standardize bag production: the water content of the culture material shall not exceed 60%; when bagging and putting on the stove, it shall not exceed 6 hours to prevent the material from turning sour. Sterilization should be maintained at 100℃ for 24 hours without temperature drop midway.

    4. Adhere to aseptic operation: the inoculation room needs thorough disinfection and sterilization, and qualified disinfectants should be selected; super-strength cleansing essence can be used, adding 10-20 kg of water per bag, spraying the space, shelf beds and site, then using disinfection boxes, no less than 5 grams per cubic meter, with a sterilization time of 1 hour. Inoculation requires passing through the alcohol lamp flame.

    5. Strictly control the spawn. Carefully select the spawn; the Xianghui mycelium of spring white fungus spawn should be stronger, to avoid ash retreat after inoculation when encountering low temperature, which affects mycelium growth. When transferring spawn, pay attention to disinfecting the inoculation box according to the spawn, and prevent bottle breakage and stopper loss during transport.

    6. Treatment of contaminated bags: treat contaminated bags differently: for light contamination, adopt bagging and tying the mouth to control spread, then sterilize and inoculate again; for severe cases, break the bag and take the material, add 1-2% lime and mix well, let it stand for 24 hours, then spread it out to dry, and use it for the next cultivation. Fruiting bodies contaminated by green mold should be harvested early; the ear base should be wiped with the clear supernatant of PH8 lime water to control spread.

    II. Eliminate pests:

    1. Fungus gnats: mainly small fungus gnats. Control measures: often clean the environment and spread lime powder for disinfection; install gauze nets on doors and windows, regularly spray pyrethrum liquid or 2000-fold Yitaibao solution; install black light lamps for trapping and killing. During the peak occurrence period, restrict the use of low-toxicity, low-residue pesticides, such as spraying 3000-fold Fipronil solution to kill, and mosquito coils can also be lit or crushed sanitary pills used for fumigation.

    2. Mites: also called fungus lice, with many varieties, commonly Pyemotes and Tyrophagus. Control methods: keep the original mushrooms away from the house material warehouse, expose to the sun before use; keep the environment clean; disinfect before opening the fungus bags, spray 3000-fold 3% Propargite solution 1 day in advance, then adjust the room temperature to 20℃, close doors and windows for empty-room disinfection, then remove the medicine smell and open the adhesive tape; when fruiting bodies in the early growth stage encounter mite damage, lay fresh tobacco leaves flat beside the fungus bags to lure the mites to gather on the leaves, then take them out and burn them to death; tea seed cake can also be ground into powder, stir-fried until oily and fragrant, then taken out of the pan and sprinkled on the mite-damaged areas, and after luring and gathering, take them out and scald them to death with boiling water. Only when there is no other way, spray 1000-1500-fold 20% Amitraz emulsifiable concentrate.

White fungus diseases and insect pests

    3. Nematodes: Control methods: sterilize the culture medium thoroughly, test the water source, disinfect the mushroom house in advance, do not spray water too wet, and pay attention to ventilation. If nematodes appear in the mushroom house, spray 0.5% lime water or 1% salt water 2-3 times on cool days, and spread lime powder for disinfection. For disease spots during the ear-growing stage, sprinkle or drip 1% glacial acetic acid or 25% rice vinegar solution.

    III. Prevention and control of diseases:

    1. Powdery mildew: also called white rot, the pathogen is Acremonium. Control methods: strengthen ventilation and dehumidification in the mushroom house; when young ears occur, spray lime-sulfur mixture, and harvest early, scrape off the roots with a sharp knife, apply 4% carbolic acid solution to the ear base, and fumigate with 50% mildew preservative powder in the evening.

    2. Rigid shrinkage disease: the pathogen is Fusarium solani. Control methods: expose raw materials to the sun, keep the moisture content of the ingredients below 60%; before uncovering the cloth at the hole mouth, spray 1000-fold 50% dichlorvos emulsifiable concentrate; after cutting the film and expanding the hole, the space humidity shall not exceed 80%; when it occurs at the young ear stage, spray PH8 lime supernatant, harvest early at the mature ear stage, and soak and clean with 5% lime water before drying.

    3. Black stalk head: Control methods: keep the fungus-growing culture not exceeding 28℃, open the mouth at the right time, cut the film and expand the hole to increase oxygen, and promote normal metabolism of the mycelium; at the young ear stage, spray water less and frequently, not excessively, to prevent water accumulation beside the ear base; at the same time, pay attention to ventilation and air exchange.

    4. Ear rot: Control methods: prevent the culture medium from turning sour; after sterilization of the material bags, pay attention to heat dissipation; prevent excessive temperature during fungus-growing culture. During the ear-growing stage of white fungus, control at 23-25℃, ventilate in time, spray an appropriate amount of water, and keep the relative humidity of the space at 85-95%. If ear rot is found on young ears, remove them in time, dig out the base, wipe with lime water, then spray 1000-fold 100% thiophanate-methyl solution; if mature ears rot, harvest early, and apply 1500-fold 25% thiram solution to control the spread of pathogens.