Key Production Techniques for Agaricus bisporus Spawn and Commercial Spawn
Summer is a great season for cultivating Agaricus bisporus. Cultivating Agaricus bisporus can make full use of the abundant crop straw resources in rural areas and is a good path to increasing income and becoming prosperous. However, the yield of Agaricus bisporus is sometimes unstable, which in turn restricts the development of this industry. Therefore, solving the technical problems of high-quality and high-yield Agaricus bisporus cultivation is very important, ...
Preparation of Wheat Grain MediumFormula and treatment: 100 kg wheat grain, 10-20 kg dried stored fermented manure-straw or chaff. 1-2 kg calcium carbonate or gypsum powder.
Wheat grain is rich in nutrients, and the mycelium grows vigorously. To prevent premature decline of mycelial vitality, adding 50 g magnesium sulfate and 100 g monopotassium phosphate per 100 kg wheat grain gives good results. Wheat grains should be plump with thick seed coats, free of insect damage and broken grains. Generally, wheat that has been stored for over a year after going through the dormancy stage has a good soaking effect, absorbing water and softening quickly.
Soak the wheat grain in 1%-2% lime water. The water surface should be 10-15 cm above the wheat grain, and it should be stirred frequently to remove floating grains. The soaking time should be flexibly controlled according to the water temperature. The standard is until the interior of the wheat grain is soaked to the point where there is no white core left. Generally, when the water temperature is around 26°C, soaking takes approximately 12-14 hours. Remove the soaked wheat grain, drain the water, then spread it on a clean cement floor to air-dry. After the surface moisture of the wheat grain has dried appropriately, it can be mixed with pre-moistened manure-straw filler grains, gypsum powder, etc. The standard for controlling water absorption of wheat grain after filling into spawn bottles is: after every 100 kg of wheat grain absorbs water and is air-dried, the wet weight should reach 136-140 kg.
Alternatively, soak the wheat grain in clean water for about 8 hours, then transfer to boiling water and boil for 15-20 minutes. When the wheat grain is thoroughly cooked (no white core) but not broken or mushy, remove, drain, and spread to air-dry. When the surface moisture of the wheat grain has dried appropriately, mix the ingredients according to the above method. This method allows the wheat grain to absorb water evenly, which is beneficial for mycelial colonization.
After the wheat grain absorbs water and its moisture is adjusted, the water content must be appropriate. If the water content is too low, the texture is hard, the mycelium penetrates with difficulty, the reproduction quantity is small, and it is prone to contamination after inoculation; if the water content is too high, the texture becomes soft and spongy, it easily breaks during sterilization, starch seeps out forming a paste, the wheat grains easily stick together into clumps, and after mycelium spreads, a mycelial mat phenomenon may occur. In addition, the water content of the filler after pre-moistening should be close to the water content of the wheat grain.
The filler is also called sealing material, guiding material, bridging material, etc. It can fix the grain medium and reduce the gaps between grains, thereby facilitating the spawn blocks to colonize and cover the surface, allowing the mycelium to spread and grow evenly, and avoiding phenomena such as mycelial breakage or mycelial mat formation caused by loosening of the grains. Commonly used fillers include manure-straw, soil, rice bran, rice hulls, etc. The amount of filler used accounts for about 10%-20% of the grain medium. Generally, it is required to be relatively fine and short. It is best if it has been crushed and fermented. When mixing, the moisture content after pre-moistening should be relatively consistent with the moisture content of the wheat grain. The dried stored fermented filler grains should not be moldy. Materials that are too long and too coarse need to be crushed. Manure-straw should be pre-moistened with lime water or clean water about 4 hours before the wheat grain is air-dried, with a pH of around 8. The water content should be 55%. Use half of the pre-moistened manure-straw as filler to mix evenly with the wheat grain, gypsum powder, etc., then fill into bottles, and use the other half of the manure-straw as the surface sealing material for the substrate.
When filling the wheat grain medium, shake up and down to help the substrate bind relatively tightly. After filling, there is no need to make holes, and conventional sterilization can be carried out. After cooling, inoculate with spawn. This method saves labor and is convenient, and is a commonly used method in large-scale production of wheat grain medium.
Sterilization time: The wheat grain structure is compact, heat penetration is slow, and the sterilization time needs to be longer. High-pressure sterilization is the ideal sterilization method. Usually, maintain at 1.5 kg pressure for more than 3 hours; for atmospheric pressure sterilization at 100°C, maintain for more than 10-12 hours.
Preparation of Cottonseed Hull Medium
Cottonseed hull is a granular-structured raw material with reasonable nutritional composition. Mycelium is not prone to excessive vegetative growth, and it is a culture material widely used for edible mushroom spawn. Using cottonseed hull as medium to produce mushroom spawn: generally 1 bottle of cottonseed hull spawn can replace 2-2.5 bottles of manure-straw spawn. When using fermented cottonseed hull as medium for mushroom spawn production, the following method can be used:
100 kg cottonseed hull, 10-15 kg dried pig and cattle manure powder, 3-4 kg gypsum powder, 0.5-1 kg superphosphate, 4-5 kg lime. First, pre-moisten the cottonseed hull, dried manure powder, and half of the gypsum powder with lime water or river mud slurry water, so that the water content is 60%-65%. After mixing evenly, build a pile. Pile height 1 m, height 1.3-1.5 m. After building the pile, cover with plastic film and make holes on the pile at intervals of 25-30 cm to facilitate ventilation and fermentation. When the cottonseed hull has fermented evenly and appears reddish-brown in appearance, break down the pile. Break it up and sun-dry for later use. Before use, adjust moisture with lime water or clean water about 4 hours in advance, so that the water content reaches 55%-60% and the pH value is 8.5-9. After filling, sterilize generally at 1.5 kg pressure for 3-3.5 hours.
Inoculation Method
Before inoculation, the bottle temperature must be lowered to around 30°C to prevent high-temperature inoculation from killing the spawn. Inoculate after cooling is complete. Each mother culture can be transferred to 3-4 bottles of spawn. Before inoculation, first clean the inoculation box (room) and spray with 2% Lysol. Then move all the sterilized spawn bottles and tools inside, and then strictly disinfect the inoculation box (room) according to conventional procedures.
Inoculation must be carried out strictly according to aseptic technique. While the inoculator takes the spawn block, open the original bottle stopper. The inoculator removes the spawn block, quickly inoculates it into the spawn bottle, then passes the cotton plug over a flame and inserts it back in place.