Key Technical Points for High-Yield and High-Efficiency Off-Season Cultivation of Oyster Mushrooms
Oyster mushrooms can be cultivated all year round, but those cultivated in the high-temperature season yield the highest returns. The reasons: First, high summer temperatures make cultivation technically difficult, and pests and diseases occur easily, often leading to cultivation failure. Second, the total cultivation area of oyster mushrooms in summer decreases, and total output is small, causing a shortage of fresh oyster mushrooms@#@125@#@ on the market and driving prices up. Based on years of cultivation practice at our edible fungi research center, as long as the key technical points are grasped and some necessary scientific management methods are adopted, oyster mushroom cultivation can still achieve high yield and high efficiency. The key cultivation and management technical points are introduced below:
1. Cultivation Points
1.1 The cultivation site should be chosen in a dark, damp place. While ensuring ventilation, the fruiting site should be chosen in a place with shade (shading), moisture retention and significant cooling effects, such as open-ground shaded cool sheds, semi-underground shade sheds, air-raid shelters, basements, cave dwellings and mountain caves; when building a greenhouse, choose a place surrounded by trees with groundwater nearby, able to create a large day-night temperature difference, which is favorable for oyster mushroom mycelial growth.
1.2 Variety selection. In principle, the variety is selected according to the temperature and other conditions of the fruiting site. There are several types of spawn: high-temperature type, medium-temperature type, low-temperature type and wide-temperature type. For summer production, high-temperature type spawn should be selected, and the mycelium is required to be thick and strong with vigorous growth: conversely, spawn that ages easily and cannot tolerate high temperatures must absolutely not be used, otherwise the yield will be greatly reduced.
1.3 The size of the cultivation bags should be reduced. In order to make full use of the substrate, increase the fruiting rate, and avoid the phenomenon of "substrate burning" at high temperatures, the length of the cultivation bags should be reduced to 40-42cm, with a diameter between 20-22cm.
1.4 Selection of cultivation raw materials. In order to ensure air permeability and avoid natural heating inside the substrate, the ideal raw material in summer should be cottonseed hulls (containing no or very little short cotton lint); choose fresh substrate free of mold; appropriately reduce the amount of nitrogen fertilizer; appropriately increase the amount of gypsum.
1.5 Control the substrate-to-water ratio. In summer, in order to control mold growth and natural heating inside the cultivation bag substrate, it is better for the substrate to be on the dry side; the substrate-to-water ratio must not exceed 1:1.1.
1.6 Building piles for fermentation, sterilized substrate cultivation. For pile fermentation, mix the substrate on a cement floor as much as possible; when piling and turning the material, do not compact the substrate, and the pile should not be too wide or too high; some ventilation holes should also be made in the pile, and the surface of the pile should be covered with plastic sheeting as little as possible or not at all, to avoid poor ventilation causing anaerobic fermentation; to increase the success rate, sterilized production should be adopted in the high-temperature season, with atmospheric pressure sterilization and inoculation at both ends. The spawn should be spread as evenly as possible, covering the substrate surface.
2. Key Points for Spawn Running Management
2.1 Cultivation time. Based on the fruiting temperature range of high-temperature type spawn being 15-36°C, with fruiting time from May to September, the best cultivation period is mixing the substrate and cultivating from mid-March to early May.
2.2 The spawn-running room should be sprayed or fumigated for disinfection in advance. For spraying, use Jinxing disinfectant or Kemeiling diluted 100-1000 times; for fumigation, use 15-20g of sulfur powder per cubic meter or 2 small packets of disinfection compound. Shading and ventilation facilities should be provided.
2.3 Arrange the bags in a well-crib pattern or run the spawn on the ground. According to temperature conditions, determine the number of layers and the distance between rows. Check the substrate temperature every day; if the substrate temperature exceeds 30°C, immediately turn the bags to dissipate heat, to prevent localized temperature rise causing "substrate burning". Keep the relative air humidity at 60%-70%, not too high, and install window screens on the vents.
3. Key Points for Fruiting Management
3.1 Stimulate fruiting. When fruiting, the bags can be stacked in 2-3 layers (with bamboo strips or wooden boards between them), with a spacing of 2-3 cm between bags, and a layer of plastic woven bags laid on the ground to ensure the mushrooms are clean. If sudden high temperatures occur, promptly splash groundwater on the ground or walls to cool down; irrigate the ground with groundwater to create a large day-night temperature difference and stimulate fruiting.
3.2 Ventilate in a timely manner to avoid deformed mushrooms. After the mycelium has fully colonized the bags and primordia appear, promptly open the bag mouths and keep the substrate at the bag mouths moist. At the same time, open doors and windows for ventilation, otherwise the mushroom stems will be slender and the caps small and thin, greatly reducing market quality.
3.3 Ensure air humidity and increase water spraying. Summer air is relatively dry, so on sunny days the number of water sprayings should be kept at 3-5 times per day. The targets of spraying are not limited to the mushrooms and substrate, but also include the ambient air, ensuring air humidity between 85%-95%.
3.4 Bag removal and soil casing for fruiting. This mainly supplements the moisture and nutrients of the substrate and increases fruiting yield. After oyster mushrooms have produced two flushes, water loss is severe, so soil casing should be used for fruiting; when casing, the soil layer should not be too thick, about 2cm. At the same time, shade and spray water. When spraying, the water volume should not be too large or too forceful; do not spray water after fruiting begins, to ensure mushroom quality.
3.5 Harvesting and management. After entering the greenhouse for fruiting management, after 3-5d, the first batch of mushrooms begins to be harvested. After harvesting, promptly clean up the residual mushroom stems and dead mushrooms on the substrate surface to prevent pests and diseases. When the second batch of mushrooms grows to about 2cm in diameter, spray "Guoduosheng" or "Zengchansu" to increase yield. After the second batch of mushrooms is picked, spray: selenium nutrient solution (a mixed solution with 0.2% salt and 2% soybean milk added) to increase the thickness of the mushroom caps and achieve high quality and high yield.
4. Prevention and control of pests and diseases. Summer oyster mushroom cultivation should focus on prevention
4.1 Before cultivation, carry out comprehensive disinfection, sterilization and pest control on the rooms and greenhouses to be used, such as spraying insecticide around the houses, spreading dry lime powder, and sterilizing the interior with formaldehyde and potassium permanganate.
4.2 At high temperatures, if pests are found during the fruiting stage, Chongmanlike, Guchongjing, Guweishi, cypermethrin, etc. can be sprayed or injected into the cultivation bags for control. For mushroom yellow disease, use agricultural streptomycin, Baoguwang, Fujunling and other drugs in alternation for control.
4.3 The main physiological diseases include withering and death of mushroom primordia, failure of cap formation, and water-soaked rot. Corresponding prevention and control measures should be taken for different causes; avoid using aged spawn, sow evenly, ventilate appropriately when primordia form, reduce the amount of water sprayed, control excessive and overly dense primordia, and effectively prevent the withering and death of mushroom primordia.