Prevention and Control of Rust spot in Pleurotus ostreatus

The ferruginous or dark brown spots on the cap and stalk of Pleurotus ostreatus are called Pleurotus ostreatus spot disease. This disease is a kind of bacterial disease which is easy to occur in the growth stage of Pleurotus ostreatus fruit body. The pathogen causing the disease is Pseudomonas aeruginosa, which is widely distributed in nature. In the early stage of the disease, the disease spot is only needle-like size, the color is also light, generally does not affect the commodity value. After the aggravation of the disease, the plaque increased rapidly, and the color deepened continuously, often in oval or fusiform shape, or connected to each other to form irregular large plaques, accompanied by yellowish discoloration areas around the plaques. When the mushroom bed is seriously infected with the disease, the fruiting body is scorched yellow, resulting in light-colored mushrooms turning into yellow mushrooms and dark-colored mushrooms turning into sauce-colored mushrooms. When the leaf spot is slightly harmful, it affects the growth and development of the fruiting body, but it does not pose a threat. After the damage is aggravated, it will not only cause the death of the fruiting body, but also affect the normal growth of the next crop mushroom, and cause cross-infection of other diseases and insect pests. The fruiting bodies harmed by the leaf spot disease have shrunk, the color is poor, and the commodity value is low. In the seriously damaged diseased mushrooms, the bacterial folds are twisted, and the spores that cannot be completely released are attached to the bacterial folds, and the cover will wrinkle and crack due to the gradual depression of the disease spot, losing its commercial value. When the temperature is high, the ventilation is poor, the water spray is too much, and the air relative humidity is more than 95%, the disease spreads quickly and the harm is serious.

Preventive measures: if rust spot occurs, ventilation should be strengthened and relative humidity should be reduced. Drug prevention and treatment can be controlled by 5% lime clarification solution, 1% bleach powder solution, 500-800 times Anso fungicide aqueous solution, containing 120 units of oxytetracycline, streptomycin, gentamicin or chloramphenicol per milliliter, or 0.5% mixture of 3 parts of bleaching powder and 1 part of soda ash. If the victim of Pleurotus ostreatus has died, or if the mushroom bed is seriously infected, all the fruiting bodies on the mushroom bed should be removed in time, the yellowing, aging and infected surface hyphae should be scraped off, and the bed surface should be cleaned up and dried slightly. Sprinkle a thin layer of lime powder or a small amount of bleach powder on the mushroom bed to reduce the number of bacteria on the mushroom bed and prevent the re-harm of leaf spot disease after stubble.