Detailed Explanation of New Anti-Contamination Technology for Bag-Cultivated Shiitake Mushrooms

Bag-cultivated shiitake mushrooms are prone to contamination. Besides reasons such as complex process technology, relatively low production technology levels, and crude conditions, it is also related to the quality of raw materials, spawn, and plastic bags, extensive production and management, the single efficacy of long-term use of purely chemical disinfectants, and the development of drug resistance in contaminant fungi. To effectively solve the contamination problem:

1. Preparation of culture medium. The culture medium can use conventional formulas such as sawdust, bran, cottonseed hulls, corncobs, and crop straw. The material-to-water ratio is about 1.0:(1.2-1.3), and the special anti-contamination agent is 0.4%-1.0%. When mixing the material, the same amount or concentration should be maintained according to the dosage ratio of the anti-contamination agent. Dissolve it in the mixing water all at once or in portions. After fully dissolving and stirring evenly, add it to the evenly mixed dry culture material. Use a shovel to repeatedly and forcefully pat and mix the culture material so that the anti-contamination agent is fully absorbed into the culture material. Once it is even, it can be bagged.

2. Bagging and sterilization. For loading material, choose high-quality polyethylene or polypropylene plastic bags (tubes) with a thickness of 0.04 mm or more, strong toughness, uniform thickness, resistance to brittle cracking, and no breaks or leaks. When making spawn, the material should be packed with moderate tightness; during cultivation, the material should be packed appropriately firm. Fill to about 6-10 cm from the bag opening, level the surface of the material, tie the bag opening tightly with plastic tying rope, or seal it by conventional methods, and then sterilize. Generally, maintain a temperature of 100°C for about 4-8 hours (4-5 hours for small bags, 6-8 hours for large bags). If the plastic bag is larger and holds more material, the sterilization time can be appropriately extended by 2-4 hours. After sterilization, take out the culture material bags and place them in the inoculation room to cool to 25°C, or after cooling, uniformly spray and disinfect the inoculation room with 1.5% anti-contamination agent (conventional disinfection methods may also be used), and inoculation can be carried out after 20 minutes.

3. Inoculation and cultivation. For inoculation, choose healthy, contamination-free spawn with strong stress resistance, fast fruiting and flushing, a relatively short growth cycle, and high yield and quality, so as to shorten the growth period and reduce disease and pest damage. When inoculating, methods such as one-end or two-end inoculation can be used. Dig out the spawn into blocks and appropriately increase the inoculation amount to promote faster mycelial growth, shorten the spawn-running period, and improve cultivation yield and quality. After inoculation, move them into the cultivation room for cultivation. For cultivation, choose an indoor cultivation room with good conditions for heat preservation, ventilation, and cooling. Before use, treat it with insecticidal and disinfectant agents, then move the inoculated culture material bags upright or horizontally onto the cultivation racks in the room, maintaining the temperature at about 20-25°C. After about 10 days of cultivation, turn the bags to check survival and whether there is contamination. If there are culture material bags that have not survived or are contaminated, pick them out of the cultivation room, investigate the causes, and take remedial measures (remove the spawn that has not survived or is contaminated, disinfect, and supplement inoculation). During the cultivation period, do a good job in heat preservation, moisture retention, cooling, bag turning and position changing, disinfection, and insect prevention. After the mycelium fully colonizes the bag, continue cultivating for a period of time. When the mycelium shrinks slightly and becomes firmer, it can be used as spawn, or fruiting management can begin.

4. Summary. This technology is most suitable for making cultivation spawn and cultivation bags from stock spawn, and can also be used to make mother culture and stock spawn. It is also suitable for spawn production and cultivation applications of various edible fungi such as oyster mushrooms, shaggy ink cap mushrooms, white beech mushrooms, and golden oyster mushrooms. If suitable natural temperatures can be fully and rationally utilized and combined with artificial regulation measures, and high-, medium-, and low-temperature types are used in combination or alternately for cultivation, year-round production can be achieved. In production, as long as key links are well controlled, such as the material-to-water ratio, thoroughly mixing the material, selecting high-quality plastic bags, maintaining a uniform concentration according to the anti-contamination agent dosage, and doing a good job in disinfection and prevention, contamination generally does not occur. If 1% anti-contamination agent is dissolved in the mixing water and the culture material is fully mixed evenly, it can be directly bagged, inoculated, and cultivated, omitting the conventional sterilization step and directly carrying out raw material spawn production and cultivation. For disinfection and control of contaminant fungi, a dosage of 1.5%-2.0% can be used. When using the anti-contamination agent, the minimum dosage should not be exceeded; there is no need to add other fungicides. If enhanced control efficacy is needed, simply increase the dosage appropriately.