Occurrence and Control of Pleurotus ostreatus Mushroom Disease
DIYAS development Limited , https://www.diyastea.com
September 05 10:13:36, 2025
In recent years, the cultivation of *Pleurotus ostreatus*, commonly known as oyster mushrooms, has seen a steady increase in planting area. However, this growth has been accompanied by rising challenges, primarily due to poor management practices and a lack of awareness regarding disease prevention among mushroom growers. As a result, the incidence of mushroom diseases has gradually increased, causing significant losses in both quality and yield. Some mushroom sheds experience recurring issues where mushrooms fail to develop properly, turning yellow, shrinking, and eventually dying. This not only reduces the market value of the oyster mushrooms but also hinders productivity. To address these problems, the author conducted an in-depth study on the causes of the disease and developed comprehensive prevention strategies. The following details are presented:
1. **Symptoms of the Disease**
The disease typically begins at the base of the young mushroom caps or the junction between the stem and cap. Infected mushrooms show yellowish spots on the cap or small recesses, followed by a sticky texture and halted growth. Affected mushrooms grow slowly, lose elasticity, and break easily upon touch. As the condition progresses, the mushroom bodies become sticky, shrink, and emit a foul odor. The disease spreads rapidly, leading to material contamination and the cessation of mushroom production.
2. **Causes of the Disease**
The primary pathogen responsible for the disease is *Pseudomonas* bacteria. These pathogens thrive in high humidity, high temperature, and poorly ventilated environments, especially where organic matter is abundant. Other contributing factors include:
- Poor sanitation in old cultivation sites with inadequate disinfection.
- Accumulation of waste materials, leftover mushrooms, and stalks within the shed, creating favorable conditions for bacterial growth.
- Use of contaminated raw or fermented materials that carry bacteria.
- Water or soil used in cultivation that may be infected.
- Low-quality or weak strains of mushrooms that have reduced resistance, leading to weaker mycelium development and vulnerability to infection.
3. **Preventive Measures**
To reduce the risk of disease, several measures should be taken:
- Select locally adapted strains with strong disease resistance, such as Heiping Wang, Huiping No. 2, and P89. Avoid planting the same strain consecutively; replace varieties every 2–3 years.
- Use healthy, non-contaminated mycelium that is thick, white, and of appropriate age.
- Choose high-quality raw materials free from mold, pests, and pollution. Expose them to sunlight before use and add bactericides like Keshiwang or carbendazim (0.1% of dry weight).
- Avoid reusing old cultivation sites without thorough sterilization. Before planting, treat the site with fungicides like carbendazim (500x), benzoic acid (500x), or bleach (200x) and spray insecticides like dichlorvos (500x) and cypermethrin (1000x) around the shed. Fumigate with sulfur for 24 hours before introducing the bags.
- Strengthen the cultivation process to improve mycelial resistance. Maintain optimal temperature and humidity during fruiting, as excessive heat can promote bacterial growth.
- Ensure proper ventilation in the mushroom shed, avoiding dead zones and adjusting airflow based on weather and temperature.
- Sterilize any soil used for covering to prevent contamination.
- Maintain cleanliness inside the shed, removing broken mushrooms after harvest and regularly applying lime powder for disinfection.
4. **Post-Infection Treatment**
If the disease occurs, immediately remove affected mushrooms, clean the surface, stop watering, and increase ventilation. Apply a 1% bleach solution to the aisles, walls, and surrounding areas. Spray the material with a 1:500 dilution of carbendazim and agricultural streptomycin, 1–2 times daily for four days. Alternate with other treatments like Huang Mouqing, Wan Xiao Ling, or others according to standard dosages to control the spread effectively.