Key Points of Agaricus bisporus Cultivation Technology to Help You Grow Successfully
Agaricus bisporus, also called white mushroom or button mushroom, is commonly known simply as mushroom. It is the most widely cultivated and highest-yielding edible fungus in the world. It has high nutritional value and good market demand (especially after China's accession to the WTO, export volumes doubled). Its main production raw materials are rice straw, corn stalks (cobs) and livestock manure, with high yields and extremely significant economic benefits. Therefore, in recent years it has developed quite rapidly in China, spreading from the traditional main growing areas of Fujian and Zhejiang in the south to Hebei, Shandong, Anhui, as well as Hunan, Hubei, Jiangsu and other places. The rise of this industry has indeed lifted many farmers in poor areas out of poverty and made them prosperous. However, in actual production, many mushroom growers start up blindly, and because they have very little grasp of the technology, losses are common. Not only do they fail to get rich, but their debts mount even higher. For those who want to seek prosperity by cultivating Agaricus bisporus, the blow is heavy. According to feedback from many edible fungus enthusiasts and our own actual investigations in many places, if you want to succeed in cultivating Agaricus bisporus, you must master the following techniques.
I. Season selection. Appropriate temperature is an important factor in the growth and development of mushrooms. Agaricus bisporus belongs to the medium-low temperature type of fungi. The mycelium growth temperature is 5-33°C; when the temperature during the spawn-running phase exceeds 35°C, the mycelium easily dies, and the temperature for fruiting and fruiting body growth must be below 23°C; above 24°C even fruiting bodies that are already growing are prone to rot and death. According to this characteristic, the cultivation time should be reasonably arranged in combination with the local natural temperature. The treated compost should not exceed 34°C after spawning, and when fruiting begins the outside temperature should be stable below 23°C. Otherwise, no matter how well the raw materials are treated, the spawn will be difficult to establish and grow; and if high temperatures occur during the fruiting period, mushroom primordia cannot form. Generally, taking the Yangtze River as the boundary, areas south of the Yangtze River choose to pile the compost in mid-August and spawn in mid-to-late September. North of the Yangtze River, the piling and spawning can be moved 20 days earlier.
2. The formula should be scientific. The button mushroom (Agaricus bisporus) is a typical saprophytic fungus and does not contain chlorophyll, so it cannot use sunlight for photosynthesis. It must rely entirely on the nutrients in the compost. Therefore, selecting and proportioning the compost is crucial and cannot be done carelessly. When selecting materials, besides being fresh and free of mold, attention should be paid to the combination and matching of various raw materials, so that the carbon-to-nitrogen ratio of the prepared compost should be 30-33:1. A large amount of manure should not be used just because there is not enough straw. If too much fertilizer is used, especially if inorganic chemical fertilizer is used excessively, in mild cases it will cause excessive mycelial growth and no mushroom production; in severe cases it will cause the spawn to fail to germinate and colonize normally after spawning, so how could one speak of successful cultivation? Here are several formulas for growers to choose from: 1. Rice (wheat) straw 2500 kg, cow manure 1300 kg, soybean cake or peanut cake powder 80 kg, urea 15 kg, ammonium bicarbonate 50 kg, calcium persulfate 30 kg. 2. Dry rice (wheat) straw 2000 kg, dry cow manure 1300 kg, cake fertilizer 60 kg, soybean powder or corn powder 10 kg, urea 30 kg, lime powder 50 kg, superphosphate 30 kg, gypsum 50 kg, light calcium carbonate 40 kg, ammonium bicarbonate 30 kg. 3. Rice (wheat) straw 5000 kg, ammonium bicarbonate 25 kg, urea 50 kg, soybean powder 20 kg, superphosphate 100 kg, calcium magnesium phosphate 50 kg, lime powder 100 kg, lime 60 kg. Corn cobs 5000 kg, barnyard manure 1000 kg, cottonseed cake 250 kg, urea 25 kg, phosphate fertilizer 150 kg, lime 125 kg. In the above combined formulas, the carbon ratio is 30-33:1, and the cultivation area is 111 sq m.
3. Pile building must be standardized. High-quality button mushroom cultivation materials must undergo standardized pile building. By relying on the reproduction of natural microorganisms to generate biological heat, the mechanism of action is: on the one hand, it can kill harmful pathogens and organisms in the material, and on the other hand, it can kill insects and eggs. A scientific pile-building method can make the material absorb water fully and ferment evenly. If the method is improper, the material will ferment poorly in the early stage, which will not only reduce yield but may even result in total crop failure.
The requirements for building a pile for button mushroom cultivation are proximity to a water source, high terrain that does not accumulate water, and convenient transportation. The pile should be built according to conventional methods by first spreading a layer 33 cm thick with a width not exceeding 200 cm and a length determined by the amount of material. Sprinkle a layer of pre-wetted manure (crushed dry cow manure should be pre-wetted one day before pile building at a manure-to-water ratio of 1:1), then place another layer of straw and sprinkle a layer of manure, and so on until the pile is about 170 cm high. Starting from the second layer, the pile material should be appropriately sprayed with 4% lime water, first less and then more, so that after the pile is completed, a small amount of manure water flowing out from the bottom is ideal. When the pile reaches 150 cm high, one should go up onto the pile and tread the straw material firmly with the feet. The completed pile should be small at the bottom and large at the top, with the top slightly higher. After the pile is built, surround it with plastic film or straw curtains. In rainy weather, the top needs to be covered with plastic film to prevent rain from soaking it.
After the pile is built, the pile temperature begins to rise. When the material temperature at a depth of 25 cm in the pile reaches 60-75°C and lasts for 4-6 hours, turn the pile. Turning the pile requires shaking the straw material loose, releasing waste gas, and enhancing the air permeability of the pile. At the same time, the straw material should be swapped from inside, outside, top, and bottom so that the raw materials ferment evenly. At this time, the pile width should be reduced to 150 cm, still piled into the original shape. If part of the material is found to be too dry, spray water during the turning process. After turning, the material temperature rises again. When it reaches 60-75°C and is maintained for 4-6 hours, carry out the second turning, with the pile-building method as before. After turning three times in this way, secondary fermentation can be carried out.
4. Secondary fermentation. After the complete compost has undergone the earlier outdoor pile fermentation, although most pests and diseases have been killed, it is not complete. At the same time, the wheat straw has a relatively high content of lignocellulose. For button mushroom mycelium, which has very low ability to decompose lignin, if such material is used for cultivation, the yield will be extremely low. Secondary fermentation must be carried out, using the reproduction of beneficial bacteria (such as bacteria, fungi, and actinomycetes) to further degrade the straw material, breaking down the original large molecular compounds into simple low-molecular compounds, so as to facilitate absorption and utilization by the mushroom mycelium. The specific method is: after adjusting the moisture of the well pre-fermented material (when a handful of straw material is squeezed tightly by hand, water droplets coming out is ideal) and adjusting the pH to 7-8, immediately load it onto the bed while hot. Place it on the middle three layers of the bed rack, with less on the upper layer and more on the lower layer, then seal it and heat it with steam, bringing the temperature inside the material to 58-62°C as quickly as possible and maintaining it for 6-8 hours. The purpose is to further kill insects and bacteria. Then, appropriately open doors and windows for ventilation, slow down heating, and let the temperature drop. When the temperature drops to 48-52°C, maintain it for 7-8 days. This stage is mainly for culturing beneficial bacteria and promoting the decomposition of the raw materials.
During the constant-temperature stage, doors and windows should be opened for ventilation for 20 minutes every day so that beneficial microorganisms can reproduce more fully. When the constant-temperature stage ends, heating can be stopped.
5. Leveling the bed is key. After the button mushroom compost has undergone secondary heated fermentation, when the material temperature naturally drops below 45°C, doors and windows should be opened immediately for large ventilation. At the same time, combine this with leveling the bed and shaking the compost loose, immediately releasing the waste gas produced by microbial metabolism in the compost (mostly ammonia), and at the same time carry out another adjustment of moisture and pH. If the material is too dry and the pH is too low, lime water with a pH of 8-9 can be used to adjust it. If the material is too wet, ventilation should be increased so that excess water can dissipate. When the material temperature drops below 30°C, spawn immediately while hot. If ammonia gas in the material has not fully dissipated, the spawn will not germinate after spawning; if the material temperature is not stable and rebounds, the spawn after spawning can also be burned to death.
6. Management must be done carefully. In edible mushroom production, cultivation is three parts and management is seven parts. Therefore, good cultivation methods and scientific management are inseparable. After the straw material is leveled on the bed and spawned, conventionally the mushroom shed needs to be closed for three days for heat preservation and mycelial growth. While sealing for heat preservation, the mycelial growth temperature should be controlled even more. Especially for early autumn cultivation, when the outside temperature is high, if the temperature inside the shed exceeds 33°C for as long as 4 days after spawning, the spawn will suffer severe damage. If the temperature inside the shed is found to be high, doors and windows should be opened at night or in the early morning for ventilation, and at the same time well water should be sprayed into the shed space and onto the ground for cooling and humidifying treatment, controlling the humidity above 85%; otherwise, the spawn blocks will find it difficult to germinate, and even germinated spawn blocks will dry, shrink, and die. Therefore, in the first three days after spawning, it is best to keep the site temperature at around 28°C so that the spawn can germinate and colonize as quickly as possible. In rainy weather, doors and windows should all be opened to facilitate mycelial growth. Three days after spawning, ventilation should be carried out for 30 minutes every day. When ventilating, if the outside temperature is high, it should be done in the early morning or at night when the temperature is low; otherwise, ventilation should be arranged at noon. About one week after spawning, the mycelium has basically covered the surface. At this time, the ventilation volume in the mushroom shed (room) should be gradually increased to promote drying of the material surface, collapse of aerial hyphae, and force the mycelium to grow into the material. About 10-15 days after spawning, a pointed wooden stick as thick as a thumb should be used to punch holes upward from the bottom of the material bed to enhance air permeability within the material and promote vigorous mycelial growth.
In short, during the mycelial growth process, management is mainly of temperature, humidity, and ventilation. The three must be coordinated. Be sure not to attend to one thing and lose another, thereby causing cultivation failure.
7. Casing soil disinfection. It must be strict. After button mushroom mycelium grows throughout the compost, mushrooms will not emerge without casing with soil. Only under the stimulation of microorganisms in natural soil (especially putrefactive Pseudomonas bacteria) can the mycelium knot and form primordia. Therefore, before button mushrooms emerge, soil must be cased on the surface of the material.
Because soil contains a large number of pathogenic microorganisms and insect pests harmful to mushroom mycelium and fruiting body growth, the soil obtained must be disinfected and treated to kill insects. Otherwise, no matter how good the mycelial growth is, it will be difficult to profit, and all previous efforts will be wasted.
After the soil used for button mushroom casing is brought back (it is best to take soil below the cultivated layer), it should be sun-dried. One week before use, it must be treated for disinfection and insect killing (the rice husk added to the soil needs to be soaked in 4% lime water for 24 hours, then removed, drained, and added to the soil and mixed evenly for disinfection). The method is for two people to spread soil while one person sprays a mixed solution of formalin and dichlorvos. The usage amount is, for every 111 sq m of cultivation area, 1 kg of formalin and 2 kg of dichlorvos for the soil. Dissolve the two chemicals in 40 kg of water and spray evenly on the soil, then build it into a pile. After spraying the solution, cover the soil pile with plastic film, press the bottom of the film firmly with soil, seal it, and fumigate for 24 hours or a little longer before use. Two days before casing, spread the disinfected soil out to dissipate the chemical smell; otherwise, after casing, the mycelium will not come up onto the soil for a long time, which will delay mushroom emergence.