Scientific Cultivation Experience and Planting Methods for Cordyceps sinensis

Dongzao Xiacao is also called cordyceps, Dongchongcao, and Xiacao Dongchong. It is the stroma of the fungus Cordyceps sinensis (Clavicipitaceae, Cordyceps genus) and the dried insect body of its host. Sweet, warm. It nourishes the lungs and tonifies the kidneys, and is mainly used for pulmonary tuberculosis, hemoptysis, deficiency asthma, night sweats, spermatorrhea, impotence, and soreness and pain of the waist and knees. It mostly grows in high-cold mountain areas, grasslands, river valleys, and among grasses. It is distributed in Gansu, Qinghai, Sichuan, Yunnan, Tibet and other provinces and autonomous regions.

Plant Characteristics

Cordyceps sinensis is a fungus-insect complex in which a fungus belonging to the class Ascomycetes, order Hypocreales, family Clavicipitaceae, genus Cordyceps parasitizes the larvae of moths of the family Hepialidae. The entire outer form is formed by the insect body and the fruiting body connected together. The exterior is yellow-brown or yellowish-brown. The insect body closely resembles a silkworm, slender and cylindrical, 3-5 cm long, about 0.3-1 cm thick, with 20-30 distinct segments and 8 pairs of legs on the abdomen, with the middle 4 pairs especially distinct. The fruiting body refers to the reproductive organ that extends outside the host insect body and is formed after repeated knotting and differentiation of hyphae, visible to the naked eye. It is relatively brittle in texture, yellowish-white in cross-section, with a reddish-brown head, and bears a stroma. The stroma is mostly solitary, slender like a club, 4-10 cm long, enlarged at the top, brown on the surface, slightly tough in texture, yellowish-white and fibrous in cross-section. The head of the stroma bears perithecia scattered or densely, and countless asci are formed in the perithecia, and within the asci are ascospores capable of sexual reproduction.

Growth Characteristics

The distribution of Cordyceps sinensis is closely related to topography, landforms, and altitude. Its host, the swift moth, prefers to grow on moist, low-temperature, sunny, well-drained terrain and landforms.

Cultivation Techniques

1. Cultivation conditions. Artificial cultivation of Cordyceps sinensis mainly requires preparing two conditions: fungus spawn and insects.

① Fungus spawn: The cultivation of Cordyceps sinensis first requires excellent pure spawn. First, it should be early-maturing and high-yielding, mainly to shorten the production cycle and reduce costs. Second, it should have strong infectivity; the spawn is required to have strong vitality, with a survival rate of 95% or more, to rapidly infect insects and cause them to sicken and die as soon as possible. Third, it should have a wide range of adaptability, especially a certain resistance to environmental temperature changes and infection by other miscellaneous fungi.

② Insects: Insects mainly use swift moth larvae as the host for Cordyceps sinensis. The larvae must be alive; larger and fatter individuals are better. The quantity is determined according to one's own cultivation. Generally, each square meter requires 1 kg of larvae, one mother culture, and 50 kg of fine sandy soil, and can produce 0.5 kg of fresh Cordyceps sinensis, 0.05 kg of dried product, worth 100 yuan.

③ Environment: Artificial cultivation of Cordyceps sinensis can be done regardless of altitude; the key depends on temperature. Cordyceps sinensis is a medium- and low-temperature fungus. The suitable temperature for mycelial growth and reproduction is 5-32°C, the optimum is 12-18°C, and 10-25°C is suitable for the formation of sclerotia and stroma.

④ Cultivation season: Using natural temperatures, two crops can be cultivated per year, in spring from March to May and in autumn from September to November. If temperature is artificially controlled indoors, cultivation can be done all year round, and the growth period can also be shortened.

2. Cultivation methods. There are many cultivation methods for Cordyceps sinensis, including indoor and outdoor bottle cultivation, box cultivation, bed cultivation, and open-field cultivation, which can be chosen freely according to one's own conditions. Regardless of the cultivation method, before cultivation the fungus-insect must first be cultured so that the insects are infected with this virus-carrying fungus liquid before entering the soil. By the time they enter the soil, they are already seriously ill and unsuitable for crawling around, which helps them die early, emerge quickly, and grow evenly. The fungus-insect culture method is to spray the prepared liquid spawn onto the larvae with a sprayer until wet, spraying twice a day. After 3 days, the larvae affected by the fungus liquid show slowed movement and a comatose state, and can then be cultivated.

① Bottle cultivation: Suitable for home cultivation. Use ordinary cans, wash them clean, first line the bottle with a layer of fine sandy soil 2.5-3 cm thick with 60% soil moisture, then place the larvae infected with the fungus liquid on top. It is best to place two larvae per bottle, requiring that the two larvae do not touch each other, with the belly facing downward and the body extended. Then cover with fine sandy soil 3 cm, and slightly press the surface flat. To maintain moisture, seal the mouth with plastic film and place it under suitable indoor or outdoor temperatures for management, avoiding direct sunlight.

② Box cultivation: Also suitable for home cultivation. Wooden boxes or plastic basins of various sizes can be used for cultivation. The bottom and sides of the wooden box should have plastic film to prevent water loss. First spread fine sandy soil 5-7 cm thick, then evenly place the fungus-insects, with each insect 2-3 cm apart, then cover with sandy soil 3-5 cm, and use plastic film on the surface to retain moisture. To save space, the wooden boxes can also be stacked.

③ Bed cultivation: Bed-frame cultivation is a development method for large-scale production. This method is generally suitable indoors and can make full use of indoor space for tiered cultivation, saving space. The bed frame is 100 cm wide, and the length is designed according to one's room. It is made of bamboo and wood, with each tier having four sides 12 cm high to retain soil. During cultivation, first lay a layer of plastic film, then pour in fine sandy soil 5-7 cm and pat it flat, place the fungus-insects with spacing as in box cultivation, cover with sandy soil 3-5 cm, and then cover with plastic film.

④ Open-field cultivation: Refers to outdoor cultivation. The key to outdoor cultivation is choosing a good site. First, direct sunlight and rainwater erosion must be avoided, and the environment should provide shade, drainage, drought prevention, and protection from trampling by people and livestock. Cultivation can be done by the flat-ground method or the furrow method. Flat-ground cultivation involves removing the topsoil 15 cm from ordinary flat land, sloped land, or wasteland, with a width of 100 cm and unlimited length, then filling with sandy soil 5 cm thick, placing the fungus-insects as described above, then covering with fine sandy soil 5-7 cm, covering the outside with plastic film, with drainage ditches around and trees or a shade shed above for shade.

⑤ Furrow cultivation: Furrow cultivation can avoid the problems of sunlight and high temperature, and is suitable for cultivation in vast rural areas. The furrow is 100 cm wide, 50 cm deep, and of unlimited length, and can likewise drain on all sides. During cultivation, first spread fine sandy soil 5 cm thick at the bottom of the furrow, then place the fungus-insects as described above, then cover with fine sandy soil 5 cm, and finally cover with plastic film. Bamboo arches are used beside the furrow, covered with straw curtains for shade and cooling.

3. Management techniques. The management techniques after cultivation of Cordyceps sinensis are very simple, mainly management of temperature, humidity, light, and air.

① Temperature: Cordyceps sinensis has relatively broad temperature requirements, generally low first and then high, but it is better to be too low and grow slowly than too high and be affected. Mycelial growth is best at 12-18°C; at low temperatures growth is slow, but there are fewer miscellaneous fungi and the survival rate is high. Generally it will not freeze to death even at -40°C, but it will die above 40°C. In the later stroma growth stage, 20-25°C is favorable for growth.

② Humidity: Humidity management is the key to the growth and development of Cordyceps sinensis. The nutrients and moisture in the insect body can basically meet its growth requirements. It does not need external nutrients and moisture; it only needs the external environment to keep the insect body's own moisture from drying out easily. Therefore, keep the sandy soil moist at all times, with a suitable moisture content of 60%. If dry, spray a small amount of clean water to maintain corresponding moisture.

③ Light: Cultivation of Cordyceps sinensis does not require strong light; it is better to avoid light. In the later stroma development stage, scattered light is better, but it must not be exposed to direct sunlight. Especially for outdoor cultivation, shading methods such as tree shade, artificial shade sheds, and straw curtain covers should be used.

④ Air: The mycelial growth stage of Cordyceps sinensis does not require much air. Especially when the stroma is about to emerge from the ground, the plastic film should be removed immediately to increase air and facilitate stroma growth, and the relative air humidity should be kept at about 75%-95%. It tends to mature 10-20 days after emerging from the soil.

Harvesting and Processing

Under natural conditions, the growth period of Cordyceps sinensis is generally 9 months. The speed of growth is mainly determined by the nature of the variety. The maturity standard is when the stroma emerges from the soil and extends 3-5 cm high, and the top develops into the ascocarp “brush tip”, at which point it can be harvested.

① Harvesting method: Use a bamboo or wooden stick to gently scrape away the sandy soil, pick out the Cordyceps sinensis, and place it in a basket. Be careful not to break the insect body from the stroma, and even more not to scrape the insect body or stroma to pieces. After collecting, rinse away the mud and sand with water, and promptly sun-dry or oven-dry it.

② Processing method: Packaged Cordyceps sinensis is made by processing loose cordyceps as raw material. That is, after the loose cordyceps has absorbed moisture again, straighten it flat, tie every 7-10 strands into small bundles with thread, and bake over a low fire until completely dry. Then 48 small bundles, tail end to tail end, are packed into iron cases, three layers, with more than 16 per layer, packed tightly and sealed, then fumigated with sulfur and dried, and tied firmly with a red silk cord along with the trademark. The specification requires that each package of cordyceps be kept at about 0.25 grams. Pack in wooden boxes, line with a layer of moisture-proof paper, bind the outside with iron straps, and store in a ventilated, dry place.