Tea tree mushroom

Tea tree mushroom (Agrocybe aegerita) belongs to the family Bolbitiaceae and the genus Pholiota (Agrocybe). It is a soil-borne wood-decaying fungus that grows in subtropical regions and is a rare edible mushroom. Its appearance is attractive, its flesh is crisp and tender, its flavor is delicious, and its texture is excellent. It is rich in amino acids and cellulose, and the protein content of its fruiting bodies is high, even higher than that of enoki mushroom (Flammulina velutipes). It is popularly praised as the "divine mushroom." Liao Hanquan, a researcher and provincial microbiology expert, believes that the tea tree mushroom variety is truly rare. Cultivating tea tree mushroom plays a major role in rationally utilizing mountain forest resources, maintaining a healthy cycle of ecological agriculture, and helping farmers become wealthy. The product can be sold fresh, canned, or dried, and is a rare edible mushroom with great development potential.

Morphology and Habits

Morphology: The fruiting bodies of tea tree mushroom are mostly clustered. The cap diameter is 2-10 cm, dark red or earthy yellow-brown, with a smooth surface and dense flesh. The stipe is 5-10 cm long and 0.5-1.2 cm in diameter, solid, with equal thickness from top to bottom or thicker at the bottom and thinner at the top. As the fruiting body gradually matures, fibrous stripes and fine hairy scales appear on the stipe.

Habits: Tea tree mushroom mostly grows naturally in spring and autumn on dead or dying parts of various poplar, elm, willow, and oil tea trees. The fruiting body has a relatively wide temperature range for growth.

Biological Characteristics

Nutrition: The mycelium of tea tree mushroom has weak ability to decompose lignin and cellulose, but has a relatively high demand for nitrogen sources. Generally, suitable nitrogen sources such as rice bran, wheat bran, corn flour, and tea seed cake powder need to be added to the culture substrate.

Moisture: The mycelium of tea tree mushroom can grow normally in a substrate with a moisture content of 46%-80%, but 60%-65% moisture content is most suitable. A relatively high moisture content promotes early budding and is beneficial for high yield. During the reproductive growth stage of the fruiting body, the relative air humidity is required to reach 85%-95%.

Temperature: Tea tree mushroom is a mesophilic fungus. The mycelium has a relatively wide suitable temperature range, with 25-27°C being the optimal growth temperature. The optimal temperature for fruiting body formation is 16-26°C. At lower temperatures, the mushroom grows slowly, but the caps are large, the flesh is thick, and the quality is good.

Light: The mycelium of tea tree mushroom does not require light for growth. Strong light inhibits mycelial growth. Primordium formation and fruiting body development require a certain amount of diffused light. Fruiting bodies cannot form under completely dark conditions. The fruiting body growth of tea tree mushroom also exhibits phototropism.

Air: Tea tree mushroom is an aerobic fungus. With insufficient air, mycelial growth is extremely slow, fruiting body formation and growth development will also be affected, and deformed mushrooms are prone to occur. Therefore, the cultivation site and culture room should be ventilated regularly to keep the air fresh and ensure uniform mushroom emergence.

pH: The optimal pH for the mycelial growth of tea tree mushroom is 5-7, i.e., neutral to slightly acidic.

Cultivation Techniques

Spawn Preparation: The formula for the spawn culture substrate is: mixed wood sawdust 50%, cottonseed hull 30%, wheat bran 15%, corn flour 3%, white sugar 1%, gypsum 1%. The production method is basically the same as that for shiitake mushroom spawn. It is best to use it within 5-10 days after the mycelium has fully colonized the bag.

Cultivation Season: Tea tree mushroom can be cultivated in spring and autumn. In spring, bags are made in February-March and mushrooms emerge in April-June; or in autumn, bags are made in August-September and mushrooms emerge in October-November.

Cultivation Method: Tea tree mushroom can be cultivated in bottles, bags, or boxes, but currently 14-17 × 33 cm polypropylene plastic bags are generally used for cultivation.

Bag Making: The main materials for cultivating tea tree mushroom are sawdust and cottonseed hull. The auxiliary materials mainly include wheat bran, corn flour, rice bran, gypsum powder, etc. All raw and auxiliary materials are required to be free from mold and deterioration. The formula for the culture substrate is: sawdust 45%, cottonseed hull 30%, wheat bran 20%, corn flour 3%, white sugar 1%, gypsum 1%, with a material-to-water ratio of 1:1.3. After mixing the materials according to the above formula, fill them into 14-17 × 33 cm mushroom bags, with 0.2-0.4 kg dry material per bag, attach a neck ring, and plug with cotton. Sterilize under normal pressure or high pressure. After cooling, inoculate aseptically, appropriately increasing the inoculation amount. Each bag of spawn can inoculate 20-25 bags.

Spawn Running Management: After inoculation, the cultivation bags should be promptly moved into the culture room for spawn running management. The culture room should be ventilated, dry, and dark. Disinfect the space once before placing the bags. The room temperature should be controlled at 21-27°C, and the spatial humidity should be controlled at around 70%. During the cultivation process, due to the growth and metabolism of the mycelium, the temperature in the culture room will gradually rise, and the indoor air will be consumed in large amounts. At this time, special attention should be paid to ventilation to avoid "mycelial burning." Generally, after 40-50 days of cultivation, the mycelium will fully colonize the entire bag.

Mushroom Emergence Management: Tea tree mushroom is generally arranged in a single layer in an upright position for mushroom emergence. When mushroom buds appear, the primordia form a coral-like shape. At this time, remove the cotton and neck ring, fold the plastic bag downward by 3-5 cm, cover with newspaper, and spray water to maintain moisture, promoting the development of tea tree mushroom fruiting bodies. If conditions permit, it is best to move mushroom buds of similar size together for easier management. As the mushroom body extends upward, gradually straighten the bag opening until harvest. Because tea tree mushroom has phototropism and the characteristic that carbon dioxide promotes stipe elongation, straightening the bag opening creates a small environment with a relatively high carbon dioxide concentration inside the bag, which is beneficial for improving the commercial value of tea tree mushroom. After harvesting the first batch of mushrooms, the second batch will begin to appear after some time. At this time, mushroom buds may not necessarily appear on the top surface. You can cut the bag at the place where mushroom buds appear so that the growing mushroom buds can develop smoothly. In the later stage, management methods such as scratching the surface or inverted mushroom emergence can also be used. Because tea tree mushroom tends to produce conjoined mushrooms, and the number of conjoined mushroom buds is relatively large, but only some of them can grow into form, and the mushroom bodies are also uneven in size, appropriate bud thinning can be adopted at this time, and some small mushroom buds should be cut off in time.

Harvesting and Processing

Tea tree mushroom fruiting bodies can be harvested when they reach 80% maturity (the veil has not cracked). After harvesting, remove the substrate from the base and bring to market@#@136@#@, or dry them with a dehydrator, then grade and package.