Mushroom rust spot also known as brown spot, bacterial spot disease. The pathogen is an acidophilic genus Pseudomonas Torrius. It is spread through the medium of insects, utensils, and workers' hands. The pH value of the mushroom bed covering the soil is below 5.5, and the ventilation is poor, and the humidity is too high. After the water spray, the fungus cover is always viscous and the disease is severe. The symptoms are: Generally it only infects the epidermis layer of the mushroom cap, causing it to initially appear yellow-brown rust-like spots of different sizes, and later it gradually turns brown or black, sometimes with mucus scars on the cap. The disease spread rapidly. When the infection is slight, the mushroom shape is normal. In severe cases, as many as hundreds of dimples appear in the mushroom cover or the lesions expand in stripes, and the fruit body is deformed. Stipes are sometimes infected and longitudinal pits occur.
Control methods:
(1) When the soil is covered, the pH of the soil layer is adjusted to 6.5 to 8, and the ventilation is strengthened during cultivation.
(2) When the disease is severe, control the temperature and humidity of the mushroom house. And 0.04% oxytetracycline and 0.04% streptomycin to mushroom bed sprayed every other day. The subsequent spraying of the mushroom bed should adjust the pH to 8 until the pH of the soil layer is maintained at 6.5 to 7.5.
(3) Spreading a thin layer of quicklime powder on the surface of the cover soil can also effectively control the disease progression.