The biological characteristics and high-yield cultivation of big fat mushroom

Mushroom, scientifically known as *Agaricus bisporus* (Quel.) Sacc., is also commonly referred to as the double-ringed mushroom or big fat mushroom. It is a high-temperature fungus that typically grows on grasslands and has been successfully cultivated in recent years. Compared to the common button mushroom (*Agaricus bisporus*), this variety exhibits greater adaptability, stronger resistance to environmental stress, and is more suitable for large-scale farming. It is more heat-resistant, drought-tolerant, and resistant to waterlogging and carbon dioxide. Additionally, it does not produce bacterial contamination or release yellow water, making it a superior choice compared to other species like *Amphora sp*. According to reports, foreign cultivation can yield between 410 to 650 kg of fresh mushrooms per ton of substrate, while domestic yields range from 310 to 350 kg per ton. **1. Morphological Characteristics** The cap of the big fat mushroom can reach a diameter of 6 to 20 cm, initially hemispherical but flattening or slightly concave as it matures. The color starts off white and gradually turns dark yellow, with no visible scales. The gills are white at first, then turn pinkish before becoming dark brown. They are densely packed, narrow, and free from the stem. The stipe is short, firm, and nearly cylindrical. A distinctive feature is the double ring, which is white and membranous, located in the middle of the stem. Spores are dark brown, broadly elliptical to subglobose, and smooth in texture. **2. Growing Conditions** **2.1 Nutrition** Big fat mushrooms primarily use cellulose, hemicellulose, and lignin found in materials like wheat straw, rice straw, and sawdust as their main carbon source. They also utilize proteins and amino acids from bran or rice bran as a nitrogen source, along with minerals and vitamins present in the culture medium. **2.2 Temperature** This is a high-temperature fungus, with optimal mycelium growth occurring between 25°C and 30°C. Fruit body development occurs efficiently at 23°C to 25°C. **2.3 Moisture Content** The ideal moisture content in the substrate is around 65%. During the growing phase, the moisture evaporates quickly, so air humidity should be maintained between 65% and 75%. During the primordium formation and fruiting stages, humidity should be increased to 85%–95%. **2.4 Oxygen Requirements** During the initial mycelium growth stage, oxygen demand is low. As the mycelium expands, ventilation becomes essential to maintain fresh air. During the primordium and fruiting stages, strong ventilation is necessary to ensure adequate oxygen supply and remove excess carbon dioxide. **2.5 Light Requirements** Light is not required during the early growth stages, and shading is recommended. However, during primordium differentiation and fruiting, the mushrooms need 100–500 Lx of diffused light. **2.6 pH Level** The culture medium should be slightly acidic, with an optimal pH of 5.5–6. Soil pH should also be slightly acidic, ideally between 5.7 and 6. **3. Cultivation Techniques** Big fat mushrooms can be grown on either raw material beds or fermented substrates. Below are detailed methods for both approaches. **3.1 Cultivation Season** Mother cultures are usually prepared from late January to late February, with original strains produced in early March. Cultivated strains are ready by mid-May to mid-June. In North China, planting is typically scheduled for mid-July to mid-August, allowing for the first harvest around September 10th. The second batch is harvested around September 20th, and the third in early October. After October 10th, lower temperatures significantly reduce fruiting. In natural conditions, three batches of mushrooms are generally harvested. **3.2 Raw Material Bed Cultivation** A mixture of 95% sun-dried cottonseed hulls, 2% gypsum powder, 0.1% chlorothalonil, 2% calcium carbonate, and 2% sugar plus 0.1% potassium dihydrogen phosphate dissolved in water is used. The moisture content should be around 65%, with a pH of 7.5. The material is spread in layers, with the first layer 5–7 cm thick, followed by a layer of spawn. The second layer is 5–6 cm, then another layer of spawn. The total thickness is 15–20 cm. After covering with plastic and newspaper, the material is kept moist. Germination occurs at 18–28°C. When the mycelium covers two-thirds of the material, a 2–3 cm layer of coal dust is added. Routine management includes proper ventilation and misting to increase humidity. **3.3 Fermented Substrate Cultivation** A mix of 40% fresh wheat straw, 57% cattle and sheep manure, 1% gypsum, 1% superphosphate, and 1% urea is used. The compost is prepared using standard biconidi mushroom techniques. Once cooled below 30°C, the material is spread in the greenhouse to a depth of 20 cm, and walnut-sized blocks of spawn are layered on top. After sowing, the surface is covered with a thin layer of spawn, and soil is added once the mycelium has fully colonized the material. **3.4 Fruiting Management** Mushroom buds typically appear about 15 days after fruiting management begins. A few days before fruiting, ventilation is reduced, and watering is increased. When the fruit bodies appear, a heavy spray is applied, and relative humidity is maintained at 75%–85%. The first batch of mushrooms is harvested approximately 22 days after soil coverage. Subsequent batches are harvested every 12–15 days. Compared to *Agaricus bisporus*, which takes about 45 days, the big fat mushroom has a shorter fruiting period of around 30 days. The yield of the first two batches is similar to that of traditional strains. Harvesting must be timely, as the mushrooms open quickly. They should be picked when the cap is 2.5–3 cm in diameter. If left too long, the caps open easily, leading to blackened gills and reduced quality. Timely harvesting is crucial for maintaining product quality and marketability.

Smart Factory

Smart Factory

Smart Factory

Automated Precision Inc. , https://www.apiasean.com