Sharing Experience on Imitation Wild Field Cultivation of Bamboo Fungus

Bamboo fungus (Phallus indusiatus) is a traditional specialty of our country, with crisp and tender flesh, excellent taste, rich nutrition, and health-promoting effects. In the past, bamboo fungus cultivation used bamboo and wood as the culture substrate, with a long cycle and low yield. In recent years, through continuous domestication and breeding of strains, new strains of grass-growing bamboo fungus suitable for growing on wild grass, crop stalks, and leftover materials have been screened out. The new cultivation and spawn production techniques are introduced as follows.

1. Substrate selection and treatment. Wild reeds, king grass, napier grass, sugarcane bagasse, rice and wheat straw, rice husks, wood shavings, bamboo scraps, corn stalks, corn cobs, soybean stalks, peanut shells, etc., can all be used as substrate for bamboo fungus, either mixed in various combinations or any one selected alone. Rice and wheat straw and rice husks should be mixed with other hard materials. Raw materials should be sun-dried and not moldy. Hard materials should be crushed with a wheel before use. Continuously add water to soak the raw materials and pile them up for fermentation. For every 100 kg (1 kg = 2 jin) of water, add 200 g potassium permanganate, 200 g urea, and 300 g superphosphate. After mixing well, continuously soak the raw materials until they absorb enough water. After watering, pile the materials into a fermentation heap 1.2 m high, 2 m wide, and of unlimited length. When the core material temperature reaches 65°C, maintain for 20 hours, then turn the pile. Turn a total of 3 times. The well-fermented substrate is brown in color, with white actinomycetes and a fragrant aroma, 70% moisture content, and pH 5.5-6.

2. Spawn preparation. Formula: 30 kg sawdust, 60 kg chopped crop stalks or sugarcane bagasse, 10 kg wheat bran, 200 g urea, 300 g superphosphate, 200 g monopotassium phosphate, 1 kg gypsum powder. Raw materials should be thoroughly dried and mixed evenly (chemical fertilizers should be dissolved first before mixing into the material). The mixed material should have 70% moisture content and pH 6. Pile the mixed material for fermentation for 3 days, then turn the pile, turning a total of 2 times. Then put into woven bags, 20 kg of wet material per bag, and sterilize in a stove, maintaining at 100°C for 10 hours before removing. After cooling, spread into prepared concave-shaped raised beds in the field. The raised beds should be disinfected and sterilized against insects 3 days in advance with 0.2% potassium permanganate solution and pesticide. The mixed material should be 20 cm thick, and inoculated with secondary bamboo fungus mother spawn, using 4-5 bottles per sq m. Break the spawn into pieces the size of pigeon eggs, with 2 layers of spawn and 3 layers of material. After inoculation, press down slightly and cover with 1 cm of soil, then cover with plastic film for shade, heat preservation, and moisture retention, keeping the temperature at 20-28°C. After 40 days when the spawn has penetrated the material, dig it up and break it into pieces the size of duck eggs for use as tertiary cultivation spawn.

3. Cultivation, sowing, and management. After the Beginning of Spring, when the temperature is above 15°C, begin sowing and cultivation. Choose fertile fields close to water sources for the cultivation site, and prepare raised beds 40 cm high and 1.2 m wide. Leave a 40 cm wide walkway between beds. Dig the raised beds into concave shapes 20 cm deep. Plant corn beside the beds in advance; after it grows tall, it forms shade with four parts sunlight and six parts shade. Disinfect and sterilize the beds against insects 3 days before sowing (method similar to tertiary spawn production). Before laying the material, apply 80 g of compound fertilizer per sq m. After watering heavily, lay the substrate. Coarse material should be laid on the bottom layer and trampled firm, with a material thickness of 10 cm. Then sow the spawn, lay a second layer of material 10 cm thick, press down slightly, and sow the second layer of spawn. Cover with a third layer of 3 cm of material so that the spawn is not exposed. After pressing down slightly, cover with 5 cm of soil. Finally, cover with film and grass for shade. Use 25 kg of dry material and 2.5 kg of spawn per sq m, with a material-to-spawn ratio of 10:1. When laying the material, adjust water if the moisture is insufficient. During the spawn-running period, maintain the temperature at 20-28°C. After the mycelium climbs onto the soil surface, lift the film every 2 days for ventilation for 30 minutes. After the mycelium covers the soil surface, lift off the plastic film to let the mycelium lie down and form primordia. At normal temperatures, mushroom emergence begins after 60 days. During the small primordium stage, spray light water to maintain moisture; during the large primordium stage, spray heavy water. Spray more on sunny days, less or not at all on cloudy and rainy days, maintaining the relative air humidity above the bed surface at 85%-95%. The time for mature bamboo fungus to extend its stalk and spread its skirt is after 6 AM each day when the eggs begin to break, so the watering time should be arranged for the previous evening after sunset. Harvest bamboo fungus when the stalk has extended but the skirt has not yet spread. After harvesting the fruiting bodies, remove the volva and cap, and immediately send them to a mushroom dehydration and drying stove, place on drying screens to release moisture. After all harvesting is complete, dehydrate and dry immediately, starting at 37°C and slowly raising the temperature, maintaining at 65°C for 1 hour, then lowering to 45°C until completely dry. After the dried product is removed from the stove, let it sit for 30 minutes, then pack into clean plastic bags and seal for sale. Bamboo fungus harvested in summer and autumn when temperatures are high and not sold in time very easily turns brown; if conditions permit, it should be stored in a freezer.

After the first flush of mushrooms, replenish with heavy water to restore the substrate to its original moisture content. The management for the next flush is the same as for the first flush. Generally, three to four flushes can be produced, with a biological conversion rate of 10%-15%, a dry product yield of 100 kg-140 kg per 667 sq m, and a production cycle of 6 months.