Symptoms and prevention methods of Flammulina velutipes blackhead disease

What should we do if Flammulina velutipes suffers from blackhead disease? How can we better prevent and treat it? Today I will tell you the method:

Pathogen of Flammulina velutipes blackhead disease

Blackhead disease, also known as bacterial brown spot disease, is a Pseudomonas, belonging to the phylum Schizomycetes, class Schizomycetes. The bacteria are rod-shaped, form white colonies, and are Gram-negative.

Symptoms of Flammulina velutipes blackhead disease

Bacterial brown spot is a bacterial disease that causes brown rot in Flammulina velutipes, which has a great impact on production. The pathogen generally only infects the surface tissue of the fruiting body and does not penetrate into the flesh of the mushroom. In the early stage of infection of the fruiting body, a small yellow or pale brown discoloration area appears on the surface of the cap, which later turns into a dark brown sunken lesion. The lesions on the cap are round, oval or irregular in shape, and the color deepens and connects into irregular large patches, causing light-colored mushrooms to turn yellow and dark-colored mushrooms to turn brown. Under humid conditions, there is a thin layer of pus on the surface of the lesions, which emits a foul smell. When the spots dry, the caps crack and form asymmetrical fruiting bodies. The morphology of the diseased mushrooms does not change much and will not cause rot. The outer periphery of the lesions on the cap of Flammulina velutipes is darker, dark brown, and the center is grayish white when it is humid. The central part is sunken when the climate is dry. The lesions on the stipes are rhombic, brown, with ring patterns, and the outer circle is darker. In severe cases, the lesions become one piece, including the entire stem, which turns brown and cannot stand upright, and has slime. Finally, the whole mushroom turns dark brown or even rots. This pathogen mainly harms Flammulina velutipes, Oyster mushrooms, and button mushrooms.

Conditions for the occurrence of Flammulina velutipes blackhead disease

The internal cause of the disease is the variety's lack of disease resistance, and the external cause is high temperature, high humidity or spraying unclean water that brings bacteria to the fruiting body. If there are water droplets on the surface of the cap for a long time or the humidity is too high, it is very conducive to the occurrence of the disease. Poor ventilation can aggravate the development of the disease. Medium temperature conditions are suitable for the disease.

Prevention and control measures for Flammulina velutipes blackhead disease

1: Keep the mushroom farm clean and hygienic, remove diseased mushrooms and waste in time; mushroom houses, bed frames, utensils, etc. should be thoroughly disinfected with 1:50 times Venus disinfectant or 2% bleaching powder before use, especially mushroom sheds with serious primary diseases.

2: When mixing the materials, the wart mold net should be mixed with water at a ratio of 1:1000. Do not use highly toxic, high-residue antifouling agents to ensure the production effect;

3: When cultivating Flammulina velutipes, the culture medium should be thoroughly sterilized. When cultivating button mushrooms and oyster mushrooms, the culture medium should be fully fermented and evenly decomposed. The covering material can be disinfected by fumigation with formaldehyde.

4: During the fruiting period of Flammulina velutipes, the temperature of the fruiting room should be controlled below 15°, and fruiting should be avoided in high temperature and high humidity seasons. Ventilation and heat dissipation should be strengthened during high temperatures. The temperature of Oyster mushroom should not exceed 18° during the fruiting period. If the temperature rises suddenly, cooling measures should be taken, such as opening windows, removing film, and shading. However, attention should be paid to the temperature fluctuation in the mushroom room not being too large to prevent condensation of water vapor and the formation of water film.

5: If diseased mushrooms are found, they should be removed in time, ventilation should be increased immediately, water spraying should be stopped or reduced, temperature should be lowered quickly, and drugs should be used to control the extent of the disease. For example, 5% lime water can be sprayed on the surface of the material, or 100-200 units of streptomycin solution or 300 units of oxytetracycline per milliliter, or 500-1000 times of bleaching powder solution can be sprayed once every two days. Water should be stopped for one day before and after the application of drugs, and drugs should be applied again after an interval of 3-4 days. Continuous use for more than three times can effectively control the spread of the disease. When the disease is serious, the diseased mushrooms should be removed first, and the surface of the material should be cleaned or covered with soil before spraying drugs according to the above method.