Stephanoma

Stephanoma phaeospora is a highly specialized mycoparasitic fungus that belongs to the group of imperfect fungi. Within the professional community of agronomists and mushroom growers, this pathogen is recognized as the causative agent of a specific disease affecting the mycelium and fruit bodies of cultivated mushrooms.

The primary target of this pathogen is commercial edible mushroom crops, particularly the button mushroom (Agaricus bisporus). The fungus actively develops on the substrate, penetrating it with its mycelium and suppressing the growth of the target culture, which leads to a critical decrease in production quality and total loss of marketable appearance.

Symptoms of the infection appear as a specific white or grayish mold on the surface of the casing soil and the fruiting bodies. Later, the affected areas darken due to the massive sporulation of the parasite. A characteristic sign is the softening of mushroom tissues followed by rotting accompanied by an unpleasant odor.

The development and rapid spread of the pathogen are facilitated by high humidity in cultivation rooms (over 85–90%) and inadequate ventilation. The optimal temperature range of +18°C to +24°C creates ideal conditions for spore germination and rapid colonization of the substrate by this mycoparasite.

The economic impact of the disease stems from the inhibition of fruit body development, leading to significant losses for mushroom production enterprises. Without timely intervention, the spores of the pathogen spread rapidly throughout the room, infecting neighboring beds, which makes strict sanitary compliance essential for management.

Protection measures include strict control of sterility during substrate preparation and the use of casing soil. Prevention is based on high-quality pasteurization of all components, regular disinfection of tools and equipment, and maintaining an optimal microclimate that prevents air stagnation and excessive surface moisture.