Several diseases of shiitake mushrooms

Friends who have grown some vegetables and crops know that any crop has diseases, and it is a headache. So today I will introduce to you the diseases of shiitake mushrooms and how to prevent them:

1. Viral diseases

Symptoms of infection: mycelium degeneration, poor growth, gradual decay, and infection of the fruiting bodies causing deformed mushrooms.

Prevention and control methods: Inject 1:500 benomyl 50% wettable powder into the infected area, and spray the mushroom farm with 500 times aqueous solution of mancozeb powder to prevent the spread of infection.

Several diseases of shiitake mushrooms

2. Bacterial diseases

① Brown rot: The pathogen is Pseudomonas fluorescens, which reproduces in the intercellular spaces of shiitake mushrooms, causing the affected fruiting bodies to stop growing, the cap, stipe and gills to turn brown, and finally to rot and stink.

Prevention and control methods: disinfect the mushroom farm and tools, remove the diseased mushrooms as soon as possible, and then spray the mushroom bags with streptomycin at a ratio of 1:50 to kill the pathogens hidden in the mushroom bags and prevent the second crop from recurring.

② Bacterial spot disease: also known as brown spot disease, the pathogen is Pseudomonas tollandii, the colonies vary in shape and size, generally gray. When the bacteria infect the fruiting body, the mushroom body will be deformed and rotten, the mushroom cap will have brown spots, and the longitudinal depression will form concave spots. If the culture medium is contaminated, the base material will become sticky and smelly.

Prevention and control methods: Remove the infected fruiting bodies immediately and spray 1:600 ​​calcium hypochlorite solution (bleaching powder) for disinfection.

3. Fungal diseases

① Green mold: It is the most harmful competitive fungus in shiitake mushroom production. The hyphae are white in the early stage, gradually turn into light green, the center of the colony is dark green, the edge is white, and it turns dark green in the later stage. In severe cases, the entire bag of fungi can turn dark green.

Prevention and control methods: Inject the affected parts with a mixture of 2% formaldehyde and carbolic acid or use carbendazim and mildew remover; you can also use the "anaerobic fermentation" method to prevent green mold: lay the seriously infected mushroom bags flat in a single layer, cover them with 3 to 5 cm of moist fine soil, and take them out after the mushroom mycelium covers the bags. During this period, they must be shaded, checked frequently, and prevented from high temperature; you can also use the temperature difference to control it. According to the different temperatures required for mushroom mycelium and green mold mycelium, the infected mushroom bags can be processed and transported out of the culture room, and placed in a cool and ventilated environment below 20°C. This can inhibit the spread of green mold and the mushroom mycelium can also grow normally.

② Neurospora: Also known as Neurospora, red bread mold. In the asexual stage, it is initially white powdery colonies, and then turns pink. It is mainly spread by conidia. It is an important fungus that occurs in July and August during the hot season. It is fierce, spreads quickly, and causes great harm. Once this fungus occurs, the strains and cultivation bags will be scrapped in batches.

Prevention and control methods: Neurospora prefers high temperature and humidity, so avoid high temperature and humidity environment first. Adding 25% carbendazim or 0.1% 75% thiophanate-methyl to the culture medium, which accounts for 0.2% of the dry weight, can inhibit the pathogen conidia remaining in the culture medium or invading during the fungus period; if the fungus bag is damaged in the early stage of fungus, use 500 times formaldehyde dilution or kerosene to drip on the incompletely formed pathogen colonies; if it is damaged in the late stage of fungus, bury the fungus bag in 30-40 cm of poorly permeable soil, and after 10-20 days of hypoxia treatment, the disease can be effectively reduced, and the fungus bag can still produce mushrooms.

③ Mucor: Also known as black mold and long-hair mold. The mycelium is colorless and transparent, and the colony is white at first. The mycelium grows very fast, about 3 cm a day, and turns gray or black in the later stage. It can be controlled by cooling, ventilation, and moisture-proofing.

④ Penicillium: The hyphae are mostly white in the early stage and are difficult to distinguish from the hyphae of Lentinus edodes. In the later stage, they turn into green, blue, gray, and liver color. They grow rapidly in an acidic environment of 20℃ ~ 25℃, competing with the hyphae of Lentinus edodes for nutrients, destroying the growth of hyphae and affecting the formation of fruiting bodies.

Prevention and control methods: Strengthen ventilation and cooling, keep clean, and disinfect regularly. If localized, use anti-mildew No. 1 or No. 2 disinfectant to inject the colony, or use formaldehyde injection to seal it.

⑤ Aspergillus: White in the early stage, black, brown, red and other colors in the later stage, with short and thick hyphae. After the mushroom hyphae are infected, they shrink quickly and emit a pungent odor, causing the mushroom hyphae to die.

Prevention and control methods: Strengthen ventilation, control water spraying, and reduce temperature and humidity. In severe cases, 1:500 times thiophanate or anti-mildew No. 1 or No. 2 disinfectant can be used to treat the diseased area.