Detailed Explanation of Key Technical Points for Field-Cultivated Shiitake Mushroom Planting and Management

Field-cultivated shiitake mushroom is a new technology developed through practical research by Hou Baocang, a large-scale edible mushroom grower in Miaohou Village, Wolong Town, Pingquan County, Hebei Province. The emergence of this technology filled the gap that fresh shiitake mushrooms could not be produced during the high-temperature season from June to September in northern China, and it has strong market competitiveness.

1. Shed construction: Build spawn-running sheds according to the number of bags planted. Generally, every 10,000 bags occupy 120 sq m. The brightness inside the shed must not be too high, otherwise it will affect the normal growth of the mycelium.

2. Material preparation: Calculated for 10,000 bags, 11 tonnes of wet coarse sawdust, 3 cubic meters of fine broadleaf sawdust, 2 tonnes of bran, 100 kg of sugar, 100 kg of gypsum and various other materials must all be prepared and used.

3. Bag filling: ① Thoroughly and evenly mix the coarse and fine sawdust, bran and gypsum, and fully dissolve the sugar in water. Evenly sprinkle the water onto the mixed material. The amount of water depends on the dryness or moisture of the sawdust. It is advisable to bring the moisture content after mixing to 65-70%. ② Use a bagging machine to fill the material into 53 cm x 15.2 cm mushroom bags. The weight of a filled bag should be 1.8-1.9 kg, and the tightness should be consistent from top to bottom. Packing too tightly easily causes the bag to burst, while packing too loosely affects yield and makes the bags easy to break.

4. Sterilization: Normally use atmospheric-pressure sterilization, with 3000-3500 bags per batch being appropriate. Use steam to bring the bags to 100 degrees C, steam for 20 hours, and eliminate harmful contaminant microorganisms in the material.

5. Inoculation: Use a sealed method to lower the temperature to below 25 degrees C, then sterilize the already-sterilized bags again by fumigation for 3-5 hours. After that, punch 4 holes on the front side of each bag, fill the holes fully and tightly with spawn, and seal them firmly with adhesive tape.

6. Spawn running: After the inoculated bags have recovered at room temperature for 2 days, raise the temperature to 18-25 degrees C for spawn running. Keep the spawn room clean. When the mycelium grows to 10 cm, puncture holes to release oxygen, and change the original stack of 4 bags together to 3, so that air can fully enter the stack. When the mycelium grows to the back side, perform a second oxygen release, with 18-22 puncture holes.

In the later stage of the spawn-running process, the bags generate heat themselves, and the temperature should be kept below 28 degrees C.

7. Moving to the field: In June, remove the outer bags of the fully run spawn bags and move them to the prepared small arched sheds, filling the gaps between the bags tightly and fully with fine sand. At the same time, use micro-sprinkling or manual watering so that the bags do not lose water. According to weather conditions, water 3-4 times per day. The shade net density of the fruiting shed should be above 90%.

8. Fruiting management: After 3-5 days of watering, the small mushroom buds will grow larger. Remove overly dense and deformed buds. As the buds grow, the amount of watering should be gradually reduced, otherwise it will affect the quality of the mushrooms. The fruiting shed must not exceed 25 degrees C. Harvest according to the quality of the mushrooms, at least 3 times per day.

9. Management after the second flush: As the number of mushrooms decreases, increase the frequency of watering to replenish moisture, so that water is fully replenished and the mycelium can rest. After the mycelium has rested, vibrate the mushroom logs with rubber or soft foam to stimulate fruiting. As the number of mushrooms produced varies, the logs will shrink, and cracks will form between the logs. Use fine sand to fill the cracks promptly.