MySheen

Control of Brown spot of Pleurotus ostreatus

Published: 2024-11-22 Author: mysheen
Last Updated: 2024/11/22, 1. The symptoms of brown spot of Pleurotus ostreatus are mainly harmful leaves and petioles, the leaf spot is dark brown and slightly round, the middle of the posterior spot turns gray-white, and the boundary between the disease part and the healthy part is obvious. when the disease is serious, the disease spot is densely spread and paralleled into patches, resulting in yellow and withered leaves. The petiole disease spot is nearly fusiform, and the disease part is slightly sunken. When the disease spot expands around the stalk and is connected, the petiole is folded. A thin white mildew layer can be seen on the surface of the disease when it is wet. two。 The route of transmission and the regularity of the disease were caused by the infection of Pleurotus ostreatus, a subphylum fungus of this disease. The pathogen is located in the mycelium or conidium.

1. The symptoms of brown spot of Pleurotus ostreatus are mainly harmful leaves and petioles, the leaf spot is dark brown and slightly round, the middle of the posterior spot turns gray-white, and the boundary between the disease part and the healthy part is obvious. when the disease is serious, the disease spot is densely spread and paralleled into patches, resulting in yellow and withered leaves. The petiole disease spot is nearly fusiform, and the disease part is slightly sunken. When the disease spot expands around the stalk and is connected, the petiole is folded. A thin white mildew layer can be seen on the surface of the disease when it is wet.

two。 The route of transmission and the law of disease

The disease is caused by the infection of Pleurotus ostreatus, a subphylum fungus. The pathogen overwintered on the corm or stump by mycelium or conidium and became the first infection source in the second year. During the growing period of Pleurotus ostreatus, the conidia produced by the disease were transmitted by airflow and Rain Water, and repeated infection was carried out. Usually warm and humid weather and partial application of nitrogen fertilizer, the plant growth is too dense, which is conducive to the disease.

3. Prevention and cure method

(1) Agricultural control: select disease-resistant varieties; strengthen fertilizer and water management, increase application of organic fertilizer and phosphorus and potassium fertilizer, avoid partial application of nitrogen fertilizer; according to the growth of Pleurotus ostreatus during germination stage, leaf extraction to corm expansion and corm formation stage, it is necessary to manage the water layer and avoid long-term deep irrigation.

(2) Pesticide control: timely drug control should be used when the seedling disease begins to occur. 70% methyl thiophanate wettable powder 1000 times liquid plus 75% chlorothalonil wettable powder 1000 times liquid, or 50% mixed thiophanate suspension, or 36% methyl thiophanate suspension 500 times liquid spray. In order to improve the spreading performance of the liquid, 0.2% washing powder can be added, sprayed once every 7 to 10 days, and sprayed for 2 times in a row.

 
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