English
Agaricus bisporus stands as the most commercially significant edible mushroom produced globally. Button mushrooms is a basidiomycete mushroom native to grasslands in Eurasia and North America. It is cultivated in more than 70 countries and is one of the most commonly and widely consumed mushrooms in the world. In the commercial cultivation of Agaricus bisporus, bacterial diseases represent a significant threat to both yield and quality. Unlike fungal pathogens, which can often be managed with fungicides, bacterial infections are highly opportunistic and closely tied to environmental management and hygiene. The “reflection” or deep dive into these diseases reveals that they are rarely the result of a single contamination event, but rather a failure in climate control. Bacteria thrive when the mushroom surface remains wet for more than 2~3 hours after watering. If the relative humidity is too high or airflow is stagnant, the “evaporative cooling” effect fails, allowing P. tolaasii to produce tolaasin, a toxin that ruptures the mushroom’s cell membranes. Bacteria are often introduced via peat moss (casing soil), irrigation water, or even mushroom flies (Sciarid and Phorid flies) acting as mechanical vectors. Pseudomonas tolaasii is a bacterium endemic to the compost beds where common mushroom (Agaricus bisporus) is cultivated. Under some environmental conditions still not well-determined, but influenced by temperature and relative humidity, the bacterium can become pathogenic and provoke the brown blotch disease. This review describes the interaction between P. tolaasii and A. bisporus that results in the appearance of brown spots on the mushroom caps, typical symptoms of the disease. This study examines P. tolaasii, detailing shifts in pathogenicity and categorizing the specific compounds responsible for tissue damage, alongside various experimental diagnostic methods. Subsequently, it addresses the mechanisms behind the browning of A. bisporus caps during infection. Future research is currently focused on molecular breeding for disease-resistant strains and the use of bacteriophages (viruses that kill bacteria) as a highly specific biological control method.
