Mycogone disease of mushrooms

Mycogone disease, widely known in the industry as "wet bubble," is caused by the fungus Mycogone rosea (also referred to as Hypomyces perniciosus). This disease is one of the most destructive fungal pathogens affecting commercial mushroom production, often leading to total crop failure if not addressed immediately.

The primary host for this pathogen is the white button mushroom (Agaricus bisporus). The fungus infects the mushroom at various stages, from the mycelium within the compost to the developing fruiting bodies on the surface of the casing layer, significantly compromising both quality and yield.

Symptoms of an infection are characterized by severe malformation of the sporocarps. Stipes become thickened and bloated, while pilei remain stunted, often forming large, tumor-like masses. A thick, white, cottony mycelial growth eventually covers the mushrooms, which later turns a characteristic reddish-brown color as spore masses begin to develop.

The development and spread of Mycogone rosea are favored by high humidity (often exceeding 90%), poor air circulation, and temperatures ranging from 20°C to 25°C. Spores are easily transported via irrigation water, contaminated tools, workers' clothing, and mushroom flies, which act as vectors throughout the growing facility.

Effective management requires a rigorous integrated pest and disease control program. Prevention strategies include:

• Strict hygiene protocols and equipment sanitation.
• Heat treatment and pasteurization of casing materials.
• Consistent monitoring of climate parameters to avoid humidity spikes.
• Prompt removal and isolation of infected mushroom clusters to prevent spore release.
• Careful use of authorized fungicides specifically registered for mushroom farming.