Soybean Disease Control Measures and Technical Key Points
Soybean Sclerotinia Stem Rot Soybean sclerotinia stem rot mainly infects the stems, and symptoms usually begin to appear in late July. In the early stage of infection, brown lesions appear on the stems, after which white cottony mycelium and white granules develop on the lesions, later turning into black granules (sclerotia). When the diseased plant stem is cut lengthwise, black cylindrical sclerotia resembling mouse droppings can be seen. After the diseased plant dies...
Soybean Sclerotinia Stem Rot Soybean sclerotinia stem rot mainly infects the stems, and symptoms usually begin to appear in late July. In the early stage of infection, brown lesions appear on the stems, after which white cottony mycelium and white granules develop on the lesions, later turning into black granules (sclerotia). When the diseased plant stem is cut lengthwise, black cylindrical sclerotia resembling mouse droppings can be seen, and the dead diseased plant turns grayish white. Chemical control: spray with 50% procymidone wettable powder at 1000 times dilution, or 40% sclerotium fungicide at 1000 times dilution, or 50% thiophanate-methyl at 500 times dilution.
Soybean frogeye leaf spot, also known as spot disease, generally begins to appear on leaves in early to mid-June, and enters its peak period in mid-July. Pods begin to be affected from the young pod stage, with the peak period occurring during the seed-filling stage, and severe outbreaks occur under high temperature and rainy conditions in July-August. It mainly damages leaves, and in severe cases nearly all leaves are covered with lesions, causing premature leaf drop; after infection, yields can be reduced by 20%-30% and soybean quality declines. Chemical control: in addition to seed treatment at sowing with 70% dexon wettable powder or 50% thiram wettable powder at 0.3% of seed weight, during the flowering and podding stage of soybean, use 40% carbendazim suspension concentrate at 100 grams per mu, mixed with 30 kg of water for spray control.