A Detailed Guide to Tremella Cultivation Methods: Three Different Cultivation Techniques
Tremella, also known as white wood ear, snow ear, tremella seed and so on, is the fruiting body of the fungus Tremella fuciformis Berk. of the family Tremellaceae, genus Tremella, and the fruiting body is used as medicine. It is a precious medicinal fungus. It is harvested in spring and autumn, cut with a bamboo knife made by soaking old spotted bamboo in lard, and the fresh tremella is washed clean with water and sun-dried. Tremella is sweet and bland in taste, neutral in nature and non-toxic; it has the effect of tonifying the spleen and stimulating the appetite, as well as replenishing qi and clearing the intestines, and nourishing yin and moistening the lungs. It can both enhance human immunity and increase the tolerance of cancer patients to radiotherapy and chemotherapy. There are more than 60 species of tremella in the world, and China is the main producing country, with an annual output of about 100,000 tons. China's artificial cultivation technique began in Tongxian, Sichuan, hence the name "Sichuan ear," and China is the earliest country in the world to cultivate tremella. Artificial cultivation in China dates back to 1894, more than 100 years ago. Now there are cultivation bases all over the country. Among them, Gutian County in Fujian has the largest output. It accounts for about half of the national output.
Tremella is also a precious edible and medicinal fungus with high economic value. It is rich in nutrients; its protein contains 17 kinds of amino acids, as well as cellulose, inorganic salts, a variety of vitamins and other nutritional components. Tremella is delicate and beautiful in form, elegant in color, and high in nutritional and tonic value, so it has always been regarded as a delicacy on the table. So, by how many cultivation methods can tremella be grown? And what techniques must be mastered for each different cultivation method?
(I) Tremella cultivation techniques are mainly carried out by three cultivation methods: log, plastic bag, and bottle cultivation.
First, log cultivation
1. Log preparation
Because the amount of nutrients contained in various tree species and whether the physical and chemical properties of the wood can meet the requirements differ, the fruiting rate, yield and quality of tremella also differ greatly.
In addition, because the natural conditions and climatic conditions of each place are different, the species and quantity of trees are also different. Therefore, before cultivating tremella, a detailed survey of the ear-tree resources of the local area must be carried out.
Excellent ear trees should have three conditions:
(1) Well-developed sapwood, small heartwood, loose wood texture, diameter of 5-10 cm, and a fast-growing broadleaf tree 3-5 years old
(2) Moderate bark thickness, not easy to fall off in the early stage of cultivation.
(3) Not prone to breeding contaminating bacteria.
There are actually many tree species that can be used to cultivate tremella: maple, Chinese tallow tree, willow, peach, apple, London plane, acacia, poplar and so on.
In addition, tree species such as pine, fir, cypress and camphor that contain bactericidal substances such as turpentine ether and alcohols, as well as aromatic substances, are not suitable for cultivating tremella.
The suitable felling period for ear trees is from leaf fall to before new buds emerge. During this period, the trees have formally entered the winter dormancy period, with rich nutrient accumulation and tight bonding between bark and xylem; especially about 15 days before the ear trees sprout, the sap begins to flow and the soluble sugar content is high, so felling at this time is most suitable.
After the ear trees are felled, they are immediately sawed into logs about 1 m long and placed in a ventilated and dry place to prevent water loss and bacterial contamination.
2. Timely inoculation
Inoculation of logs should preferably be carried out at above 15 degrees; spring inoculation is generally between March and April: autumn is better from October to early November.
The logs need some treatment before inoculation. First, check the moisture content of the logs. Then carry out sterilization treatment, arranging the logs on the ground for a "sunbath," using sunlight to kill contaminating bacteria on the surface of the logs. Lime water or copper sulfate can also be applied to the cross sections at both ends of the logs.
When inoculating, first use a belt punch, electric drill or hand drill to make inoculation holes in the logs.
After the holes are made, take the spawn out of the bottle with tweezers, put one piece into each hole, and then tap it firmly gently with a small iron hammer.
3. Stacking for mycelial growth
In order to promote earlier development of the spawn and maintain good heat preservation and moisture retention for management, the form generally used is stacking for mycelial growth.
For stacking for mycelial growth, choose a wind-sheltered, sunny, well-drained, clean and hygienic site, and arrange the logs in a regular stack in a well-crib pattern; the four corners touching the ground should be padded with 10-15 cm bricks, and the stack height should be about 1.5 cm; after stacking, seal the whole stack from top to bottom with plastic film, then cover the film with straw curtains or branches. Finally, fix and tie the covering with rope.
After stacking, observe the temperature changes; the temperature inside the stack should preferably be kept at 24-27 degrees. Usually, when the inner wall of the film is covered with water droplets, it indicates suitable temperature and humidity.
Under suitable growth conditions for the spawn, 3 to 5 days after inoculation, white feather-like mycelium can be seen recovering and growing into the wood; this is the sign that the feather-like fragrant ash mycelium has survived.
4. Turning the stack to even out the mycelium
Because the microclimatic conditions at different positions inside the stack, top and bottom, inside and outside, are different, the mycelial growth among the logs is also different. In order to promote balanced mycelial growth and uniformity, the stack needs to be turned.
The first turning of the stack is carried out 7-10 days after stacking, then once every seven days; when fruiting is approaching, turn once every 3-4 days. The whole mycelial growth period is 45-50 days, with 6-7 turnings in total. During turning, adjust the temperature at any time.
5. Arranging the yard for fruiting
When the mycelium in the logs develops to a certain stage, it must shift to reproductive growth, and tremella primordia begin to differentiate and form inside the holes; at this point the logs must be moved to the fruiting site for yard arrangement and fruiting.
There are multiple forms of yard arrangement for fruiting, such as indoors, tunnels, under tree shade, shade sheds, air-raid shelters and so on; the commonly used forms are tunnels and indoors.
Tunnel cultivation: tunnel cultivation should be dug in a wind-sheltered, sunny, well-drained, ventilated and shaded place; its specifications are 2-3 m wide, 2 m at the tunnel bottom, and the tunnel length is adapted to local conditions. A drainage ditch is dug below the tunnel, and a shade shed is built above the tunnel to protect against wind and rain.
Indoor cultivation: this means placing the logs in a ventilated, breathable, heat-preserving and moisture-retaining, clean house for cultivation and fruiting. For the arrangement form, they can be stood upright against the four walls, or placed horizontally on shelves. The advantages of indoor cultivation are saving labor and time and being easy to manage; the disadvantage is that heat preservation and moisture retention are not easy.
6. Management to increase fruiting
During the fruiting stage, management of temperature, humidity, air and other aspects must be handled well. If the weather is hot and stuffy, cooling work must be done well. If contaminating bacteria are found on the fruiting bodies, they can be moved outside the yard, rinsed with 5% lime water, dried in the sun, and then moved back to the original place; if rotten ears are found, they should be dug out in time. After each batch of tremella is harvested, stop spraying water for 5-7 days to let the mycelium recover its strength, and then grow the next batch of fruiting bodies.