Latest Cultivation Techniques and Methods Tutorial for Black Wood Ear Mushroom

Black wood ear mushroom is a high-quality, delicious gelatinous edible and medicinal fungus. China's black wood ear mushroom production areas are divided into three regions: the Northeast region——Liaoning, Jilin, Heilongjiang. The Central China region——Shaanxi, Shanxi, Gansu, Sichuan, Henan, Hebei, Hubei. The Southern region——Yunnan, Guizhou, Guangxi, Guangdong, Hunan, Fujian, Taiwan, China, Jiangxi, Shanghai. Black wood ear mushroom has a delicate texture, is crisp, smooth and refreshing, and is rich in nutrients. Its protein content is far higher than that of ordinary vegetables and fruits. It also contains amino acids essential to humans and multiple vitamins. Among these, the vitamin B content is ten times that of rice, noodles and vegetables, and 3—6 times higher than that of meat. Its iron content is 100 times higher than that of meat. Its calcium content is 30—70 times that of meat, and its phosphorus content is also higher than that of eggs and meat, being 4—7 times that of tomatoes and potatoes.

Black wood ear mushroom has effects such as nourishing and strengthening the body, clearing the lungs and boosting qi, calming and relieving pain, and cleansing the stomach and intestines. The polysaccharides it contains also have significant antitumor activity. It is a commonly used formula medicine in traditional Chinese medicine for treating conditions such as cold-dampness lumbar and leg pain, hand and foot cramps and numbness, hemorrhoid bleeding, dysentery, uterine bleeding and postpartum weakness. It is a health food for workers in textiles, cement, mining, cleaning and chemical plants. The nucleotide substances in black wood ear mushroom can lower cholesterol levels in the blood. Therefore, in 1980, American merchants suggested that China grind black wood ear mushroom into powder or granules and enter the U.S. market as a medicine. They were very optimistic about the sales prospects of black wood ear mushroom as a medicine in the United States, because heart and blood vessel diseases had become the number one disease in the United States. China had long conducted research on the medicinal use of black wood ear mushroom. In the Ming Dynasty, Li Shizhen wrote in the “Compendium of Materia Medica”: “……fasting to treat hemorrhoids……, abnormal uterine bleeding, and bloody dysentery”.

Because black wood ear mushroom has high nutritional value and medicinal value, it sells well in both international and domestic markets, and the product is in short supply. China ranks first in the world in black wood ear mushroom output. It is a traditional bulk export specialty and enjoys a high reputation in the international market. Therefore, fully exploring and rationally utilizing the natural forest resources and crop straw in mountainous areas and vigorously developing black wood ear mushroom production has important practical significance for revitalizing local economies and expanding foreign trade exports.

In the early period, China's black wood ear mushroom production areas used old cultivation methods. Some relied on the natural spread of black wood ear mushroom spores; some relied on the spread of mycelium from old wood ear logs; and some used crushed wood ear mushroom for inoculation. In the 1950s, after arduous efforts, Chinese scientific researchers successfully cultivated pure strains and applied them to production, changing the long-standing semi-artificial cultivation state. This not only shortened the production cycle of black wood ear mushroom, but also achieved doubled output growth, with quality also significantly improved.

Since the 1970s, research on substitute-material cultivation of black wood ear mushroom has also been carried out in China, and it has now been applied to production. Substitute-material cultivation of black wood ear mushroom uses sawdust, corn cobs and rice straw as raw materials, and uses containers such as glass bottles and plastic bags to cultivate black wood ear mushroom. Substitute-material cultivation has abundant resources, high yield and a short cycle, and is a cultivation method with development prospects.

Biological Characteristics of Black Wood Ear Mushroom

In plant taxonomy, black wood ear mushroom belongs to the phylum Fungi, class Basidiomycetes, subclass Heterobasidiomycetidae, order Tremellales, family Auriculariaceae, genus Auricularia.

In recent years, foreign countries have also attached great importance to black wood ear mushroom production, but except for Japan, the black wood ear mushroom produced abroad is not true black wood ear mushroom; most of it is a closely related species of black wood ear mushroom——hairy wood ear mushroom. Because the growth environment of hairy wood ear mushroom is the same as that of black wood ear mushroom, and it is also quite widely distributed in China, and its appearance is also very similar to black wood ear mushroom, people in China often mistakenly regard hairy wood ear mushroom as black wood ear mushroom.

The fruiting body of hairy wood ear mushroom is thick and fleshy, and cultivation is easier than that of black wood ear mushroom. Its yield is much higher than that of black wood ear mushroom, but its quality is lower than that of black wood ear mushroom. It tastes crisp and is not easy to chew thoroughly, and its quality is far inferior to black wood ear mushroom. At present, its market price is about 1/3 of that of black wood ear mushroom.

Morphological Characteristics of Black Wood Ear Mushroom

In nature, black wood ear mushroom grows laterally on dead wood. It is composed of three parts: mycelium, fruiting body and basidiospores.

1. Mycelium: The mycelium of black wood ear mushroom is composed of many villous hyphae with septa and branches. Monokaryotic hyphae can only be observed under a microscope. The mycelium is the nutritional organ through which black wood ear mushroom decomposes and absorbs nutrients. It grows on wooden sticks, substitute materials or slant culture media. If it grows on wooden sticks, the wood becomes loose and white; if it grows on a slant, the mycelium appears grayish-white and villous, adhering to the surface. If cultured in a petri dish for plate culture, the mycelium grows outward from the inoculation block as the center, forming a circular colony with neat edges. When the mycelium grows under strong light, it secretes brown pigment, causing the culture to become brown, and yellow or light brown appears on the surface of the mycelium. In addition, if the culture time is too long, the mycelium gradually ages and also shows the same characteristics as culture under strong light.

2. Fruiting body: also called the basidiocarp, namely the edible part. It is a gelatinous mass interwoven from many hyphae. When young, it is granular; when small, the fruiting body is cup-shaped, and during growth it gradually extends into a flat, wavy shape, namely the ear piece. The ear piece has dorsal and ventral sides. The dorsal side has hairs, and the ventral side is smooth and has a hymenium. Under suitable environmental conditions, it produces basidiospores. The fruiting body is elastic when fresh, and brittle and hard when dry, with a darker color.

3. Basidiospores: usually a uninucleate haploid structure, kidney-shaped, about 9—14 micrometers long and 5—6 micrometers wide. When a large number of basidiospores gather together, a layer of white powder can be seen.

Growth Cycle of Black Wood Ear Mushroom

The growth and development of black wood ear mushroom goes from basidiospore——mycelium——fruiting body——basidiospore, which is called one life cycle or one generation.

The sexual reproduction of black wood ear mushroom is carried out through heterothallic mating, and only hyphae of different mating types can combine to complete its life history. Black wood ear mushroom is a bipolar mating system of heterothallic mating, controlled by a single factor, with “plus” and “minus” different sexes. After germination under suitable conditions, basidiospores of different sexes produce monokaryotic hyphae, which are called primary hyphae.

Primary hyphae are initially multinucleate, then quickly produce septa, dividing the hyphae into multiple monokaryotic cells. When two monokaryotic hyphae, each carrying “plus” and “minus”, combine and undergo nuclear fusion, dikaryotic secondary hyphae are produced, also called dikaryotic hyphae.

Each cell of the secondary hyphae contains two nuclei of different properties. Through clamp connections, the dikaryotic hyphae cause the two daughter cells produced by division to both contain the same two nuclei as the mother cell. It is thicker and stronger than primary hyphae, grows faster and has strong vitality. The strains cultivated artificially are secondary hyphae.

The secondary hyphae absorb large amounts of nutrients and water from the surrounding environment and multiply in large quantities. The hyphae intertwine alternately, and the dense hyphae growing in the substrate form the white fuzz visible to the naked eye, which is the mycelium. After a certain period, the mycelium gradually transforms into the fruiting body of the reproductive body, and fruiting body primordia grow on the substrate. By absorbing large amounts of nutrients and water from the substrate, the gelatinous and elastic black wood ear mushroom fruiting body gradually forms.

The mature fruiting body produces club-shaped basidia on its ventral side. The basidia then extend small branches from the sides of the four arranged cells, and basidiospores are produced on the small branches. The basidiospores are ejected from the fruiting body through special ejection organs on the fruiting body, disperse with the wind, find a suitable substrate, and begin a new life cycle again. Under suitable conditions, the entire life cycle takes about 60—90 days to complete.