Detailed Explanation of Key Points of Shiitake Mushroom Bag Cultivation Techniques

1. Raw Material Preparation

(1) Wood Slicing

Insert wood segments with a moisture content above 20% into the feed inlet of the slicer, cutting them into chips about 4 mm thick with a cross-section of 60×20 mm.

(2) Raw Material Grinding

Put sun-dried wood chips, or bagasse, oil-tea camellia shells, and straw stalks into a dedicated grinder or feed grinder (with a special iron sieve of about 2 mm mesh), processing them into powder.

2. Culture Material Formulation

(1) Culture Ratio

Main materials such as sawdust and bagasse account for 78%, wheat bran or rice bran 20%, sugar 1%, gypsum powder 1%, plus superphosphate 0.5%, urea 0.2-0.3%, magnesium sulfate 0.1-0.2%, and 50% carbendazim 0.1%. The main materials can be used alone or mixed from two or more types.

(2) Formulation Method

Mix the main materials and auxiliary materials by dry stirring. Soluble substances such as sugar, urea, magnesium sulfate, and carbendazim should be dissolved in water, then added to the dry materials and thoroughly mixed. The moisture content should be kept at around 55%.

3. Bagging

Use polyethylene tubular plastic bags with a diameter of 15 cm and a length of 50 cm for filling. When bagging by hand, compact layer by layer, keeping the tightness consistent from top to bottom, so that it does not indent when squeezed by hand. Raw material slicing, grinding, mixing, and bagging can all be mechanized, offering high speed and good results, and have been widely applied.

4. Sterilization

After filling, tie the bag opening tightly, seal it by melting with a candle flame, move it into a normal-pressure stove, stack layer by layer, close it up and light the fire, maintain at 100°C for 10 hours, let it sit for a period, then take it out.

5. Inoculation

Move the sterilized material bags into the inoculation room while still warm, stack them in a "well" pattern to cool, close the doors and windows, and fumigate and disinfect with a mixture of formaldehyde and potassium permanganate for 2-3 hours. When the material temperature drops below 30°C, inoculation can be carried out. During inoculation, use a small conical wooden stick with a diameter of 2 cm to punch inoculation holes, 2 cm deep, 4-6 holes per bag, using single-sided or double-sided inoculation. Inoculation is done by three people working together, punching holes, inoculating, and stacking at the same time. The spawn is required to fit tightly with the hole opening, leaving no gaps.

6. Spawn Running

After inoculation, move the spawn bags into a ventilated, dry, cool, and dark culture room, and stack them in a "well" pattern for spawn running. Because the temperature is high at this time, temperature control and ventilation management must be carefully done to avoid contamination by foreign microorganisms and to reduce the pure culture rate.

7. Mushroom Yard Setup

The mushroom yard should be chosen in a wind-sheltered, sunny, open area with large day-night temperature differences, flat terrain, and close to a water source, or in idle winter paddy fields after rice harvest. Dry land must be strictly disinfected and insect-killed, and paddy fields should be burned dry in advance, then plowed and leveled into mushroom beds. The bed width is about 1 m, height 15 cm, length 10-15 m, with a 30 cm walkway left between beds. A soaking ditch is dug in the middle, 60 cm wide and 60-80 cm deep. The soil dug out from the ditch is piled onto the beds, making the bed surface turtle-back shaped. On both sides of the bed, wooden stakes 0.5 m long are driven in at 2.5 m intervals, buried 20 cm into the soil, with horizontal wooden strips on top. On the wooden strips, 2.5-inch-long iron nails are nailed at 20 cm intervals, with the nail heads exposed 2 cm, and bamboo poles are laid across in sequence to serve as leaning racks for mushrooms. A shade shed is built over the rack yard, tightly enclosed around with straw curtains, and the shed roof is covered with fir branches or thatch.

8. Bag Removal and Color Turning

When the spawn bags have been cultured until the area around the inoculation holes is light brown, the mycelium around the bag wall has swelled into a wave-like shape, the protruding parts feel elastic and soft to the touch, and some primordia have appeared, bag removal can be carried out. The method is: use a sharp blade to gently cut open along the length of the bag and remove the plastic bag, then place it on the mushroom bed rack. After bag removal, cover strictly with plastic film for 3-5 days, and do not turn or move as long as the temperature inside the mushroom bed does not exceed 28°C. When the fuzzy mycelium on the surface of the spawn log reaches 2 mm in length, ventilation should be strengthened and light increased to promote the fuzzy mycelium to lie down. After the dew dries each day, lift the film for ventilation 1-2 times, 30 minutes each time, and combine with spraying atomized water to regulate humidity. If the fuzzy mycelium still does not lie down, the film can be uncovered in the afternoon for ventilation for 3-4 hours, or 2% lime water can be sprayed to force the fuzzy mycelium to lie down. After 7-8 days, it gradually turns color and yellow water droplets appear. If dark green water droplets appear, ventilation should be strengthened, combined with spraying clean water to rinse, and the film should be covered after the surface of the spawn log is air-dried until it is not sticky to the touch. After 10-15 days, when the surface of the spawn log forms a mycelial membrane and turns brown, it can be transferred to fruiting management.

9. Fruiting Management

After the spawn logs turn color, temperature difference stimulation should be carried out in time to induce budding and fruiting. The specific method is: cover the film tightly during the day so that the mushroom bed temperature reaches above 20°C, and lift the film for ventilation for 1-2 hours from midnight to early morning, causing the mushroom bed temperature to drop suddenly. For 3-4 consecutive days, mushroom buds will be produced in large numbers. After fruiting begins, ventilation management should be strengthened, 1-2 times daily, 30 minutes each time, combined with water spraying adjustment, maintaining the relative air humidity of the mushroom yard at 85-90%. After harvesting one flush of mushrooms, stop watering for 3-5 days, then continue spraying water for 5-7 days to promote the next flush of mushrooms. In autumn, the spawn logs have sufficient nutrition, high moisture content, and suitable temperature, so fruiting is abundant and concentrated, and generally no soaking is needed. However, when the spawn logs are too dry to fruit, soaking treatment can be carried out appropriately. In winter, medium- and low-temperature varieties can still fruit normally in the south, and management should be strengthened to strive for more mushrooms. In cold regions, fruiting is not suitable, and only spawn cultivation for overwintering can be carried out, allowing alternating dry and wet conditions to rejuvenate the mycelium and actively accumulate more nutrients. After the temperature rises in spring, mushrooms can be produced in large quantities, but the spawn logs lose much water, so soaking is needed to replenish moisture. Before soaking, first open the film and let the spawn logs dry fully until the moisture content drops to about 35%. Before the low temperature arrives, use No. 8 iron wire to punch holes 6-8 cm deep from both ends, then neatly arrange them in the soaking ditch and soak for 6-8 hours, so that the content reaches about 60%, then take them out and rearrange them on the mushroom bed rack for fruiting. Also pay attention to timely cleaning of the site and doing a good job in pest and disease prevention and control.