Detailed Explanation of Key Techniques for Summer Cultivation of Shiitake Mushrooms

Summer fresh shiitake mushrooms have traditionally been a gap in the edible mushroom market. With the development of technology, high-temperature strains have entered production in recent years. The author advocates using water-temperature air conditioning for fruiting, along with medium-to-wide temperature strains, which has significantly raised the market price of the product. The main measures are:

1. Facility or equipment requirements. Cultivation facility: an ordinary edible mushroom greenhouse. After completing spring production, clean up promptly. After removing the original mushroom bags, clean the inside of the greenhouse, check and repair the greenhouse film, and spray an appropriate amount of medication such as Baibing Qusongwu to sterilize. Then, fill the greenhouse with clean water. After the water seeps down, spread lime powder inside the greenhouse, and the mushroom bags can then be moved onto the shelves. Cooling equipment: a water-temperature air conditioner can cool for production in summer and also heat for cultivation in winter, serving two purposes with one machine and delivering excellent results. In the 2006 summer off-season shiitake cultivation trials, it could reduce the fruiting greenhouse temperature to 20-25°C, with very good results.

2. Mushroom bag preparation. Basic formula: sawdust 1800 kg, wheat bran 200 kg, superphosphate 20 kg, urea 3 kg, lime powder 20 kg, gypsum powder 10 kg, shiitake-specific additive 1 kg. Routine management for bagging, sterilization, inoculation, and spawn running.

3. Mushroom bag color change. After spawn running is fully complete, stack the white mushroom bags in a crisscross pattern to a height, and cover with plastic film, straw mats, etc., so as to raise the temperature while regulating the covering of straw mats and plastic film and uncovering them at night. This serves, first, to cause the white mycelium on the surface of the bags to lie down, and second, to increase the temperature difference of the bags, prompting them to change color as quickly as possible. For the color change management of the mushroom logs after removing the bags, in order to increase the temperature difference and remove the pigment secreted on the logs, water should be sprayed to rinse them. Other management is the same as above.

4. Temperature regulation to induce budding. After the color-changed mushroom bags have been perforated and supplemented with water and other treatments, they can be moved into the greenhouse and arranged in a single layer at intervals of about 5 cm. Cooling is carried out through the water-temperature air conditioner. After 1-2 days, high-temperature stimulation is then applied. Combined with stimuli such as water and light in the greenhouse, small mushroom buds appear in about a week. After that, maintain routine watering and minimize humidity differences as much as possible to ensure a continuous emergence of mushroom buds. The basic management indicators at this stage are: keep the temperature between 20-25°C, as low as possible; air humidity between 75%-95%. Because shiitake mushroom caps are relatively thick and can tolerate relatively large humidity differences, there is no need to worry that too large a humidity difference will cause death; by adjusting the covering on the greenhouse roof, keep the light intensity in the greenhouse at 300-1200 lux; moderate ventilation to keep the air in the greenhouse relatively fresh.

5. Fruiting management. The plastic film on shiitake mushroom bags is relatively thick, and the mushroom buds cannot break through the bags on their own, so the plastic film must be cut open manually. The method is: at the place where mushroom buds appear, use a small blade to cut open the plastic film, being careful not to damage the mushroom buds. If management is careful, the plastic film can be cut in a circular opening around the mushroom buds, which can avoid deformed mushrooms to the greatest extent. From the time the young buds emerge, the fruiting management stage begins. At this stage, maintain: temperature at 20-25°C, humidity between 75%-95%, light at about 500-1000 lux, and appropriate ventilation. When the cap diameter reaches more than 2 cm, the three-dimensional edible mushroom nutrient essence can be sprayed directly on the fruiting bodies. When the edge of the shiitake cap is still curled downward (copper gong edge) but shows a tendency to expand, it should be harvested promptly. To a certain extent, the greenhouse temperature and foliar fertilization at this stage will determine the level of shiitake yield and quality. Using mushroom logs for fruiting management is more convenient than using mushroom bags, but because the logs are exposed, they lose more water during fruiting, so humidity should be increased, and soaking the logs or water injection treatment should be provided. The flushes of shiitake are relatively obvious. After one flush is harvested, the mushroom bags lose water rather seriously, so water supplementation and spawn resting are needed, and only then can the next flush be managed and harvested. The common method of water supplementation is: use existing ditches, channels, pits, or dig an earthen pit, line it with plastic film, arrange the mushroom bags inside, and when about 20 cm from the upper edge, lay a plastic film to form a concave shape, fill the concave area with water, and after a certain pressure is formed, pour water into the pit with the mushroom bags. After it is full, maintain for 24 hours, then drain the water, place the mushroom bags back on the fruiting shelves, and refer to the above management.