Soybeans are being damaged by sudden death syndrome (SDS) in area fields. The damage shows as patches in fields. Some fields are showing dramatic damage whereas others are showing lighter damage. Those fields with lighter damage are infected but the damage is not as severe.

SDS leaf symptoms are yellow spots between leaf veins and these lesions increase and turn brown. Leaf veins remain green. Eventually the leaves die and fall off. The petioles remain on the stem. Pods and seeds can be aborted.

SDS fungus can reproduce on the root surface and spores are purple blue. Digging plants north of Corning on the Missouri River bottom, the spores were easily seen. This fungus is known as Fusarium virguliforme.

The fungus infects the soybean root system early season. Field specialists in agronomy suspect that the range in symptoms in which they see badly damaged fields whereas others are slightly damaged is the result of wet soil conditions after planting.

SDS management includes planting soybeans with SDS resistance, adding effective fungicide seed treatments and improving soil drainage. Once you have the disease, there is not an effective control to eliminate the disease. Even using all the tools available, you will have yield loss.

For more information, contact Wayne Flanary, Field Specialist in Agronomy, University of Missouri Extension at 816-279-1691.