Northern Research and Demonstration Farm
Soybean sudden death syndrome (SDS) is caused by the Fusarium virguliforme fungus. This fungus infects and grows in the plant’s roots. The fungus produces a toxin, which is transported into the leaves and causes foliar yellowing, browning, and finally early leaf drop. Root infection and toxin production are highly affected by environment and irrigation, and early planting is important to ensure a good screening test.
Iowa State University
Cianzio, Sylvia R.; Gebhart, Gregory D.; and Lundeen, Peter, "Soybean Sudden Death Syndrome Field Screening" (2009). Iowa State Research Farm Progress Reports. 583.