Identifying and controlling S. sclerotiorum
S. sclerotiorum mainly infects stems. The onset of disease began in late July, with brown lesions on the stems. White cotton flocculent mycelium and white particles were later found on the lesions, and black particles (sclerotia) later changed. Longitudinal stalks of diseased plants, black sclerotia like cylindrical mouse can be seen, the diseased plants often withered white, it is also called dead lice disease, white peony disease. The sclerotia of sunflowers and other crops are the same type of pathogens as soybean sclerotia and can infect each other. The disease is caused by sclerotia mixed in the seeds and sclerotia in the stem overwintering and the second year of infection. Sclerotia can survive in soil for 2 years. Helianthus annuus soybeans, heavy soybeans, low-lying soybeans, and high-density, high-yield soybeans have been weighed heavily. In the end of July and August, the incidence of heavy rainfall was heavy. Control methods: 1 Agricultural control. Select seeds to remove sclerotia, turn over the soil in the fall, change crops for rotation, and remove diseased plants to burn off. 2 chemical control. Can be used 50% fast Skeleton WP 1000 times; 40% sclerotium net (weak raging) WP 1000 times; 50% thiophanate-methyl WP or 50% carbendazim WP 500 times spray, About 40 kg of liquid per 667 square meters.