Because the symptoms of SDS appear similar to many other soybean diseases, SDS can be easily overlooked, according to Damon Smith, Extension Field Crops Plant Pathologist at the University of Wisconsin Extension. Planting resistant varieties, keeping an eye on the weather, and scouting your fields are just a few of many management practices that the University of Wisconsin Extension recommends to keep SDS from fooling you.
The name sudden death syndrome (SDS) is descriptive in that normal-appearing plants turn yellow and die rather quickly after pod set.
SDS may be overlooked because its symptoms are similar to those of brown stem rot (BSR), a common soybean disease in Wisconsin. However, SDS does not cause internal stem browning, which is a key symptom of brown stem rot.
Yield losses due to SDS range from 20-80% or more, depending on variety and stage of crop development when the symptoms first appear. Appearance of the disorder at early pod fill is reportedly more damaging than its appearance at a later stage of plant development. Yield reduction is the result of reduced photosynthetic area, defoliation, flower and pod abortion, and reduced seed size. Like brown stem rot, SDS is associated with growing conditions optimal for high yield.