Clever Use of Oyster Mushroom Spent Substrate to Grow High-Quality Shaggy Mane Mushrooms

The shaggy mane mushroom (Coprinus comatus) gets its name because its shape resembles a chicken leg; its flesh is tender, delicious and nutritious. Using spent oyster mushroom substrate and idle vegetable greenhouses, shaggy mane mushrooms can be produced. A 60 sq m mushroom shed can take in 1000 kg of dry substrate and produce 750-1000 kg of shaggy mane mushrooms, with a market price of more than 4000 yuan, giving considerable economic returns. The specific cultivation measures are as follows:

1. Prepare the growing substrate. Crush the spent oyster mushroom substrate, and mix it in the ratio of 50% mushroom bran, 37% cottonseed hulls, 6% lime, 7% corn flour, and 0.1% carbendazim (added separately). First mix the mushroom bran and cottonseed hulls evenly, then add quicklime and corn flour and mix well, then spray water onto the substrate, treading it firmly while spraying to prevent moisture loss, so that the substrate moisture content reaches 70%.

2. Build the pile for fermentation. Pile the mixed substrate into a pile 1.5 m wide, 0.6-1 m high, and of unlimited length. At the bottom of the pile, lay two rows of sorghum stalks bundled to a diameter of 20 cm, spaced 60 cm apart, as air channels; on the pile, insert two rows of sorghum stalks bundled to a diameter of 7-8 cm vertically at intervals of 40-50 cm for aeration. Spray the pile once with insecticides such as beta-cypermethrin to prevent insects, then cover with torn plastic film or straw mats to keep warm and retain moisture. After 48 h the temperature can rise above 60°C.

3. Turn the pile. When the temperature rises above 60°C (measured on the shady side at 50 cm above the ground) and is held for 24 h, the pile can be turned. When turning, start from one end, move the substrate from the bottom layer and outermost layer of the pile to the middle, and move the middle substrate to the bottom and outer layers, then rebuild the pile for fermentation. When the substrate temperature rises above 60°C again and is held for 24 h, carry out the 2nd turning; generally 3-4 turnings are needed, and the fermentation period is generally 6-10 d. If the substrate is too dry, water it appropriately when turning. Each time a pile is built, if sunny weather occurs, shade it with straw mats or corn stalks; on rainy days cover it with plastic film to prevent rain, and remove the film when it is sunny again, otherwise the natural ventilation of the substrate will be affected. Successfully fermented substrate has a large amount of white actinomycetes, no sour or ammonia smell, and a special winy aroma.

4. Bag filling and spawning. After the raw materials have been piled and fermented, bag filling and spawning can be carried out. Cut plastic tubes into mushroom bags about 50 cm long, and tie off one end. When the substrate temperature drops to 30°C, begin filling the bags. Use the 5-layer "edge inoculation method" for spawning, with 4 layers of substrate. First put in 1 layer of spawn, then 1 layer of substrate, and finally seal the opening with spawn. Break the spawn into pieces the size of walnuts, and try not to break the spawn into small crumbs. In this way, fill layer by layer with one layer of spawn and one layer of substrate, and finally tie the bag opening tightly. The spawning rate is generally 12%-15% of the substrate weight.

5. Management during the spawn-running period. Use a combination of the micro-pore aeration method and punching holes in the middle to speed up spawn running. With the filled mushroom logs, use iron nails or toothpicks to make about 10 small holes at the spawn locations, then transport them to the spawn-running site. If running spawn inside a shed, level the ground in the shed beforehand, spread a thin layer of lime powder, arrange the mushroom logs upright, with row spacing of 8-10 cm, leaving a 40 cm walkway every 6 rows for observation. Insert several thermometers between the mushroom bags, and record the temperature once each morning and evening. Control the temperature of the mushroom bags at 20-28°C, with a maximum not exceeding 30°C and a minimum not lower than 10°C; the temperature of the mushroom bags can be controlled by uncovering or covering the plastic shed film or adjusting the ventilation openings. Keep the relative air humidity in the shed at about 70%, maintain a good ventilation environment, cover the shed well with straw curtains, and spray beta-cypermethrin once every 7 d inside the shed to prevent insects.

6. Bag removal and casing soil. About 20 d after bag filling, the mycelium will have grown throughout the bags. Because shaggy mane mushrooms will not fruit without contact with soil, the bags can be removed and casing soil applied 3-5 d after the mycelium has grown throughout the bags. First dig mushroom beds in the shed running north-south, 15 cm deep and 1.5 m wide, then water the beds thoroughly; after the water has seeped down, remove the plastic bags from the spawn-run bags, and finally cover with 2-3 cm of casing soil. For the casing soil and filling soil, it is best to choose high-quality fertile garden soil; generally mix 2% lime into the soil, spray 0.1% dichlorvos and 0.2% potassium permanganate, mix well, pile it up, cover with plastic film and seal for 3-4 d to kill insect eggs and contaminating microorganisms. The soil moisture should be such that it forms a ball when squeezed in the hand and crumbles when touched. After casing, cover with plastic mulch to keep warm and retain moisture, maintain the temperature at 14-25°C, and spray water once every 7 d.

7. Fruiting management. After the mushroom logs are placed in the beds, management focuses on temperature regulation, humidification and ventilation, with an appropriate amount of light. The fruiting temperature should be controlled at 12-22°C; water and ventilate every day, keep the relative air humidity in the mushroom shed between 85%-95%, and ensure fresh air. After about 20 d the mycelium can grow out of the soil layer and form primordia; at this time, remove the plastic mulch, do not spray water on the primordia, control temperature and ventilation, and gradually increase the amount of water sprayed as the young mushrooms grow. Generally the fruiting bodies mature in 7-10 d.

8. Harvesting. Harvest in time when the fruiting body cap has elongated and is elastic, and the ring on the edge of the cap has just begun to loosen while still tightly wrapping the stipe. When harvesting, grasp the lower part of the stipe with the hand and gently twist to pull it up. After harvesting, tidy the substrate surface, remove the mushroom bases, re-cover soil where there is none, spray once with a heavy watering, cover with film, and after 10-15 d of cultivation the 2nd flush of mushrooms can appear. The management of the 2nd flush is the same as the 1st flush, and each cultivation cycle produces 5-6 flushes of mushrooms.