Efficient Cultivation Techniques for Oyster Mushrooms Grown on Corncobs

It is estimated that every 100 kg of corncobs can produce 100-150 kg of fresh oyster mushrooms, with a biological conversion rate of 150%-250%. Material selection and processing. Select fresh corncobs from the current year that are free of mold, expose them to sunlight for 2-3 days, and crush them to the size of corn kernels; screening is not required. Preparation of the growing substrate.

Reference formula: corncobs 79%, soybean straw 15%, lime 4%, gypsum 1%, superphosphate 1%, urea 0.3%. Preparation method: first dissolve the lime and urea in water, then mix them into the material, with a water-to-material ratio of 1:1. After the material is turned and mixed evenly, pile it and let it sit for 2 hours. Pile fermentation. Spread plastic film on the ground and build a pile 1.5 m wide and 1 m high, with unrestricted length. Randomly punch several holes through to the bottom from the top of the pile, then cover with plastic film or straw curtains for pile fermentation. After 1 day, measure the pile temperature. If it reaches above 60°C, maintain it for 6 hours, then turn the pile, moving the outer material to the inside and the inner material to the outside, then pile it again. Ferment until it reaches 60°C, maintain for 12-24 hours, then break up the pile; fermentation is then complete.

Filling and inoculation. When the material temperature drops below 30°C, it can be bagged. Use 50 x 25 cm polyethylene tube bags and inoculate using the three-layer material, four-layer spawn inoculation method, that is, one layer of spawn at each end and two layers of spawn in the middle, with the spawn amount inoculated in a 3:2:2:3 ratio. The sowing amount is 10%-15% of the material weight. Tie the mouths of the inoculated bags, stack them toward both sides and upward, to a height of 1.5-2 m.

Mycelial cultivation. Two days after sowing, the material temperature begins to rise. Pay attention to changes in material temperature every day. Turn the pile once after 2-3 days, and turn it again after 6-7 days, to prevent the material temperature from rising above 35°C. When the material temperature rises to 32°C, promptly open doors and windows, spray water on the floor, reduce the number of stacked layers, and spread out the spawn bags so that heat inside the bags can dissipate quickly, thereby lowering the material temperature. The material temperature in the spawn bags is best kept at around 25°C. After about 10 days, rotate the spawn bags 180 degrees so that accumulated water at the bottom seeps back, which helps uniform mycelial growth. After about 20 days, turn the bags again. Place bags with good mycelial growth together and poor ones together; remove contaminated bags. For lightly contaminated bags, open the bag mouths and place them in a cool place to air for a few days, or cover them with lime powder; for heavily contaminated bags, move them far away and bury them deeply. Keep the indoor relative air humidity at about 65%. Generally, after about 30 days, the mycelium will have fully colonized the spawn bags.

Fruiting management. When the surface of the substrate is covered with white mycelium, untie the closures on both sides of the bag and roll the bag mouths outward, strengthen ventilation, keep the room temperature at 14-18°C, and control relative air humidity at 85%-90%. During the primordium stage, absolutely avoid spraying water. When young mushrooms appear, spray a small amount of water. When they grow to the size of broad beans, increase the frequency of water spraying and maintain air humidity at 90%. At 10-25°C, they can be harvested after 5-7 days. After harvesting the first flush, cut away the remaining mushroom fragments, spray water heavily once to seal the substrate surface as before, keep the indoor air slightly drier to promote mycelial growth and nutrient accumulation, and strengthen ventilation and light transmission. After the second flush forms, carry out normal management. After harvesting 2-3 flushes, spray 0.2%-0.3% urea or potassium dihydrogen phosphate. During the entire growth period, the temperature should be controlled at 10-25°C and the humidity at 80%-95%.

Harvesting. Oyster mushrooms take about 40 days from sowing to harvest. When the caps are at eight-tenths maturity, the fruiting bodies are heaviest and the yield is highest. When harvesting, hold the mushroom stem and twist it out, or cut the entire cluster from the base with a small knife. Do not pull forcefully, so as not to damage the substrate surface and affect later flushes. Over the entire growth cycle, 5-6 flushes can be harvested.