New technique for semi-underground arched shed cultivation of reishi mushroom

The method of cultivating reishi mushroom by stacking fungus bags into walls and covering with soil in a semi-underground arched shed has many advantages. First, a semi-underground shed costs less to build than a ground-level shed, saving 40% on shed construction costs; second, water management is convenient, as it is only necessary to keep the casing soil layer adequately moist; third, mushrooms emerge from one end, concentrating nutrients, so the reishi mushrooms grown are robust and of good quality; fourth, a semi-underground arched shed is warm in winter and cool in summer. When the outdoor ground temperature is around 40°C in summer, the temperature inside the shed does not exceed 36°C, and in winter it is 3°C--4°C higher than ground level. The skylights on the shed roof can meet the light requirements and provide ventilation. The technique is briefly described as follows: 1. Site selection and shed construction: Choose a sunny, clean site and dig a pit 3 m wide, 3.3 m wide, 1.5 m deep and 40 m long. Over the pit, erect A-frame supports with moso bamboo every 1 m, first lay asphalt felt, then cover with straw mats, and open skylights alternately on the roof every 1.5 m. After the shed is built, fumigate with sulfur smoke to kill insects, then fumigate and disinfect with potassium permanganate or formalin solution, and finally scatter lime on the ground. The arched shed built has an area of 120 sq m. 2. Preparation of culture substrate: The formulas used are: ① 88% cottonseed hulls, 8% wheat bran, 1% each gypsum and lime, 2% phosphate fertilizer; ② 44% cottonseed hulls, 44% sawdust, 10% wheat bran, 1% each sugar and gypsum; ② 78% sawdust, 20% wheat bran or fine rice bran, 1% each sugar and gypsum. The water content is about 65%, and the pH is 6.5--7.0. After mixing the substrate, immediately fill plastic bags, with about 500 g of substrate per bag. Then sterilize, either by autoclaving for 2 hours or by atmospheric sterilization at 100°C for more than 8 hours. Use the two-end inoculation method, tie the openings with string, and after inoculation place them in the arched shed for mycelial growth, with 5--6 bags per layer. Change positions weekly to balance substrate temperature, and check for contamination by foreign fungi, promptly removing contaminated fungus bags. Generally, after culturing at 25°C--30°C for about one month, the mycelium can fully colonize the substrate. 3. Semi-unbagging, soil covering and primordium formation: Take the fully colonized fungus bags and cut a ring around the middle of the substrate with a blade, then remove the upper half of the plastic bag while keeping the lower half. Place the unbagged end facing outward along the long side of the arched shed in horizontal rows, fill the gaps between fungus bags with soil, and after arranging one layer of fungus bags, cover with about 3 cm of soil and spray water so the soil absorbs enough moisture. Then arrange the next layer in sequence, for a total of 6--8 layers. In the middle of the shed, place bags with both ends unbagged facing each other, also arranging 6--8 layers, still covering with soil. In this way, three fungus walls are formed for reishi mushroom production, with 2 walkways 70 cm wide between the fungus walls. After one week, cut away the exposed plastic bag at the tied openings and manage conventionally to let the mushrooms emerge. The key management point is to maintain soil moisture. The watering method is to spray water on the upper layer of the fungus wall and let it seep downward, preferably in small amounts but frequently, maintaining air humidity at 80%--95%. During the mushroom emergence stage, open the skylights for ventilation and pay attention to disease prevention and pest control. Add nutrient solution while spraying water.