Key Technical Points for Bag Cultivation and Management of Tea Tree Mushroom
Tea tree mushroom (Agrocybe aegerita), originally a wild mushroom growing on the roots of tea trees in the high mountain dense forests of Guangchang, Jiangxi. It is a pure natural, pollution-free health food mushroom that combines high protein, low fat, low sugar, and health-promoting dietary therapy. The optimized and improved tea tree mushroom has tender caps and crisp stems, a pure delicate aroma, and an excellent taste. It can be cooked into various delicious dishes, and its nutritional value exceeds that of shiitake and other edible mushrooms, belonging to the premium edible mushroom category.
Morphological Characteristics of Tea Tree Mushroom
The fruiting bodies are solitary, paired, or clustered. The cap diameter is 5-10cm, the surface is smooth, initially dark reddish-brown with shallow wrinkles, and the flesh (except for the surface and the base of the stem) is white with fibrous stripes, solid in the center. At maturity, the stem hardens, the stem is covered with a dull viscous substance, and the annulus remains on the stem or attaches to the cap margin and falls off automatically. The inner surface is often covered with spores and appears rust-brown; the spores are elliptical and light brown.
The cap is initially born, then gradually flattens, with a shallow center, brown, and lighter margins. The flesh is white and thick. The gills are adnate or indistinctly remote from the stem, initially brown, later light brown. The stem is solid, 4-12 cm long, light yellowish-brown. The annulus is white, membranous, and superior. The spores are ovoid to elliptical. Tea tree mushroom and the poplar mushroom, Agrocybe cylindracea, Agrocybe cylindracea, willow mushroom, willow ring mushroom (Guizhou, Yunnan), and willow pine mushroom (Japan and Taiwan, China) belong to the same species. However, varieties such as the poplar mushroom, Agrocybe cylindracea, Agrocybe cylindracea, willow mushroom, willow ring mushroom (Guizhou, Yunnan), and willow pine mushroom (Japan and Taiwan, China) differ considerably from the tea tree mushroom in morphology and quality. The tea tree mushroom is clearly superior to the poplar mushroom and other varieties in taste, aroma, food and medicinal value, and economic value.
Bag Cultivation and Management Techniques for Tea Tree Mushroom
1. Selection and breeding of superior mushroom strains: At present, there are many tea tree mushroom strains. The tea tree mushroom strains promoted earlier in the Guangchang area of Jiangxi Province include AS78, AS982, etc., bred by the Mushroom Strain Preservation Center of Ganzhou Region, Jiangxi Province. In recent years, the tea tree mushroom strains promoted in Fujian Province include Tea Tree Mushroom-1, Tea Tree Mushroom-3, Tea Tree Mushroom-5, etc., bred by the Sanming Fungus Research Institute. The strain production is as follows: Mother culture (first-level spawn): use enriched PDA medium (potato 200g, glucose 15g, sucrose 5g, magnesium sulfate 0.5g, monopotassium phosphate 0.5g, B1 1g, water 1000ml) or wheat bran-added PDA medium (potato 200g, sucrose 20?g, wheat bran 10g, water 1000mL). Both formulas use agar 20g. Generally, the latter formula produces thicker and stronger mycelium. The mother culture made with the above formulas can be cultured at a constant temperature of about 26°C for about 7 days.
Stock culture (second-level spawn): use sawdust medium (sawdust 78%, wheat bran 20%, sucrose 1%, gypsum powder or calcium carbonate 1%, a small amount of superphosphate, magnesium sulfate, and monopotassium phosphate). The stock culture is cultured at a constant temperature of about 25°C for about 7 days.
Cultivation spawn (third-level spawn): use sawdust medium or cottonseed hull medium (cottonseed hull 78%, wheat bran 20%, sucrose 1%, gypsum powder 1%). The spawn is cultured at 24-28°C for about 30 days. Tea tree mushroom spawn requires thick, strong, dense white mycelium. In the later culture stage, reddish-brown markings sometimes appear on the mother culture slant, or small fruiting bodies like those of enoki mushroom appear on the surface of the stock culture or cultivation spawn; these are normal phenomena. However, if the mycelium is sparse, weak, and thin, does not completely colonize the substrate, has mottled spots, or produces yellow liquid, it should not be used.
2. Cultivation season: Because tea tree mushroom is relatively resistant to high temperatures and can also tolerate low temperatures, it can be cultivated year-round in most areas of Fujian, Guangdong, Zhejiang, and other provinces. However, cultivation in different seasons results in different yields and quality, so to achieve high yield and high efficiency in tea tree mushroom cultivation, the appropriate cultivation period must be selected well. According to cultivation trials in various places, spring or autumn cultivation is suitable in most areas of our country, especially spring cultivation, which gives a higher yield. In production, spring cultivation is generally arranged when the temperature reaches 20°C, and autumn cultivation when the temperature drops to 25°C for fruiting. Each place can choose the appropriate cultivation period according to local climatic conditions. For example, in the eastern Fujian area, the suitable spring cultivation period is bag making from January to February, fruiting in April to May, or bag making from September to October, fruiting in November to December.
Bag Making and Cultivation Management
1. Substrate formula: According to the raw material situation in each place, choose the formula based on benefit. Reference formulas include: a. Tea branch powder (or cottonseed hull) 77.5%, wheat bran or rice bran 20%, gypsum powder 1%, sucrose 1%, superphosphate 0.5%. c. Straw powder 38%, sawdust or cottonseed hull 38%, wheat bran or rice bran 19.5%, gypsum powder 1%, sucrose 1%, superphosphate 0.5%, tea seed cake 2%.
2. Bag making: Mix according to the quantity and ratio required for production, add water and stir the materials. The material-to-water ratio is preferably about 1:1.2. Raw materials must be fresh, free of mold, and free of pests. Mix thoroughly and evenly; especially, cottonseed hulls must not have dry particles, otherwise sterilization will not be thorough. Use low-pressure polyethylene plastic bags with specifications of 15-17cm×35cm×0.05cm. Each bag has a dry material weight of about 350g and a wet weight of 720-750g. Fill with appropriate tightness, height 14-15cm, slightly level the surface, promptly put on the neck ring and insert the cotton plug (or tie tightly with woven thread) to prevent water evaporation and loss. Then carry out atmospheric pressure sterilization (raise the temperature to 100°C within 4 hours, keep for 12-14 hours). Tea tree mushroom has weak resistance to contaminating microorganisms, so sterilization must be thorough. During the production process, strictly prevent bags from being punctured or abraded, to prevent contamination by foreign microorganisms.
3. Bag inoculation: After sterilization, inoculate only after the material temperature drops below 30°C. The inoculation box or inoculation room should be fully disinfected. The inoculation amount is 30-40 bags per bottle. After inoculation, culture in the dark. Tea tree mushroom mycelium recovers and colonizes slowly and is prone to contamination by foreign microorganisms and pests. Therefore, after inoculation, pay attention to keeping the culture room clean, dry, and ventilated, prevent the effects of high and low temperatures, and promote uniform mycelial growth. Check frequently. If bags contaminated by foreign microorganisms are found, promptly remove and handle them to prevent spread. Generally, after inoculation, the mycelium can fully colonize the bags in 30-40 days.
4. Fruiting management. Under normal conditions, tea tree mushroom can fruit about 50 days after inoculation. Before fruiting, carry out pinning induction management. During pinning induction, the bags can be placed upright or stacked in a wall-type arrangement. Then remove the cotton plug or cut the tying thread, straighten the bag mouth, and arrange the bags to induce pinning. For upright placement, place about 80 bags per square meter. Let the mycelium shift from vegetative growth to reproductive growth. The color of the substrate surface also changes accordingly; at first there is yellow liquid, then it turns brown, and small mushroom buds appear. During this period, increase the relative air humidity and maintain it at 95-98%, and spray water in the morning and evening to keep moist. Control light intensity at 500-1000 lux and temperature at 18-24°C, so that a large number of fruiting bodies appear 10-15 days after opening the bags.
After fruiting, appropriately lower the spatial humidity and reduce ventilation. At this time, lower the relative humidity of the cultivation space to 90-95%, and reduce the frequency and duration of ventilation, to prevent excessive oxygen from easily causing early veil opening, short stems, and thin flesh. If the mushroom buds are too dense, thin them out, keeping 6-8 per bag, with a moderate number, uniform growth, good shape, and thick stems; otherwise, the quality and yield of the mushrooms will be affected. When the cap of the tea tree mushroom fruiting body begins to flatten and the annulus has not yet fallen off, it should be harvested. Because the tea tree mushroom stem is relatively brittle and easily broken, when harvesting, grasp the base and pull it down, while preventing damage to young mushrooms. After harvesting, clean the substrate surface of the bag, pinch the bag mouth closed, let the mycelium rest and recover for 2-3 days, then pull open the bag mouth, give one heavy watering, and repeat the above management. After 5-7 days, another flush of mushrooms can grow, and a total of 4-6 flushes can be harvested.
Prevention and Control of Diseases and Pests
During bag making and cultivation management, tea tree mushroom often suffers from contamination by foreign microorganisms and invasion by diseases and pests. Therefore, during cultivation, prevention and control of diseases and pests must be strengthened. Common foreign microorganism contamination during tea tree cultivation includes green mold, red Neurospora, Rhizopus, etc., and the control measures are the same as those for shiitake cultivation. The common pest damage in tea tree mushroom cultivation is from the larvae of mushroom gnats and mushroom flies.