Detailed Explanation of Artificial Cultivation and Processing Techniques for Polyporus umbellatus

Polyporus umbellatus is a medicinal fungus belonging to the Polyporaceae family, with its sclerotium used as medicine. Polyporus umbellatus has the functions of promoting diuresis and draining dampness, resolving phlegm, and detoxifying, and has long been a commonly used traditional Chinese medicinal material. Recently, it has also been found to have anti-cancer effects.

Polyporus umbellatus is distributed in most regions of China, parasitizing the roots of trees and shrubs, mainly maple, birch, oak, maple, and poplar. The sclerotium is perennial and grows underground. The age of the sclerotium can be determined from the color of its surface: generally, those over 3 years old are dark brown; those 2—3 years old are grayish yellow; and newly formed sclerotia of the current year are clear white.

With the decrease of wild resources and the continuous rise in demand, the supply-demand gap is increasing year by year, and Polyporus umbellatus is bound to become a promising highlight variety of traditional Chinese medicinal materials. The artificial cultivation and processing techniques are introduced as follows:

I. Environmental Requirements Polyporus umbellatus is suitable for growing on loose, moist, sunny slopes at 20℃—50℃. It is sensitive to temperature changes. When the temperature is below 8℃ or above 25℃, it stops growing and enters a dormant state. The most suitable temperature for the growth period is 15℃—24℃. For cultivating Polyporus umbellatus, slightly acidic or nearly neutral sandy loam or loess with a pH of 5—6.7 should be selected, with humus loam being particularly suitable. Polyporus umbellatus cannot be autotrophic, nor can it directly parasitize trees; it must rely on Armillaria to provide nutrients. Polyporus umbellatus has low requirements for nitrogen, phosphorus, and potassium fertilizers, and generally does not need fertilization after planting.

II. Cultivation Methods

1. Fungal material cultivation: Armillaria is the nutrient source for the growth of Polyporus umbellatus. Before cultivating Polyporus umbellatus, the fungal branches, fungal sticks, and fungal beds of Armillaria must first be cultivated.

① Fungal branch cultivation: From March to August, select companion tree branches with a diameter of 1cm—2cm, cut them into small sections 6em-10em long, soak them in 0.25% ammonium nitrate solution for about 10 minutes, and set aside. Dig a pit with length, width, and depth of 60cm×60em×30cm respectively. Spread a thin layer of leaves at the bottom of the pit. Place the soaked branch sections tightly and flatly in 2 layers in the pit. On top, place roots or fungal materials carrying Armillaria fungal elements tightly, then cover with a thin layer of soil, and then place another two layers of branch sections. Repeat this arrangement for 6—7 layers. Finally, cover the topmost layer with soil 5cm—6cm thick, and cover with leaves for protection. Cultivate for 40 days and it is ready.

② Fungal stick cultivation: Saw the selected broadleaf tree trunks and branches with a diameter of 6cm-12cm (preferably Fagaceae plants) into sections 40cm-80cm long. On the wood sections, cut a small notch every 10cm—15cm deep to the xylem, and inoculate Armillaria spawn at the notch. Build the inoculated wood sections into a well-shaped frame and cultivate at a temperature of about 15℃ for 2—3 months. Alternatively, following the fungal branch cultivation method, place the log sections at the bottom of the pit, laying 100—200 log sections tightly and flatly per layer, adding 2—3 Armillaria branches between two layers of logs, filling gaps with soil, laying a total of 4—5 layers, and covering the top layer with soil 10cm thick.

③ Fungal bed cultivation: Generally carried out from June to August or from October to March of the following year. First dig a pit 30cm deep and 60cm square. Spread a layer of leaves at the bottom of the pit, place 3—5 fresh companion tree log sections with a spacing of 2cm-3cm, place 2—3 fungal branches, cover with a thin layer of sandy soil, and then cover with soil 10cm thick.

2. Cultivation of sclerotium

① Preparation of spawn: After harvesting Polyporus umbellatus in summer, dry the fruiting bodies immediately (never smoke, sun-dry, or expose to rain), knead into powder, and the reproductive spore spawn is ready. Alternatively, select small, nodular, uneven-surfaced Polyporus umbellatus to use directly as spawn.

② Planting of spawn: In April—May and November, first plow moist but non-waterlogged fertile mature soil, add humus soil, rake level, and dig holes 30cm-50cm deep. The hole must have companion tree roots or 3 cultivated fungal materials placed in it. Inoculate the sclerotium at the places among the fungal materials where Armillaria rhizomorphs are vigorous, and fill gaps with leaves, then repeatedly place fungal materials and sclerotia layer by layer according to the above method. Alternatively, place a layer of Polyporus umbellatus spawn directly on the bottom fungal material, and finally cover with humus soil or sandy soil. It is also possible to dig open the cultivated fungal bed, take out the upper layers of fungal sticks, spread Polyporus umbellatus sclerotia directly on the bottom layer of fungal sticks, fill gaps with leaves, then place fungal sticks and Polyporus umbellatus sclerotia according to the above method, and finally cover the top layer with soil 30cm thick.

III. Field Management After cultivation, pay attention to keeping the soil of the cultivation site moist. During the dry season, water and irrigate in time. During the rainy season, pay attention to drainage and waterlogging prevention, and strictly prevent trampling by people and livestock.

IV. Harvesting and Processing 1. Harvesting: Generally, dig and harvest 2 years after planting. The harvesting seasons are April—May or September—October, and select grayish-brown sclerotia with soft bodies to keep as seed sclerotia. 2. Processing: The dug-out Polyporus umbellatus should be cleaned of sand and soil and impurities with a brush; it must not be washed with water. Place in sunlight to sun-dry or air-dry, then store in a ventilated place. 3. Grade standards: Grade A: large sclerotium blocks, black surface, firm texture, white flesh; Grade B: small sclerotium blocks, gray epidermis, rotten and broken sclerotium body, shrunken and not solid, brown flesh.