Cool spring soils and high rainfall in areas of the Corn Belt may lead to a midsummer appearance of sudden death syndrome (SDS) symptoms in soybeans, say DuPont Pioneer experts. The severity of SDS depends on environmental conditions, time of infection and other crop stressors. Although SDS infects soybean plants just after germination and emergence, symptoms generally do not appear until midsummer.

Soybean SDS varies in severity from area to area, and from field to field. That’s why growers must clearly understand the extent of an SDS infection in each of their fields to effectively manage the disease, says Steve Schnebly, DuPont Pioneer soybean researcher.

SDS leaf symptoms first appear as yellow spots, usually in a mosaic pattern on upper leaves; the yellow spots coalesce to form chlorotic blotches between leaf veins. Infected leaves, appearing about midseason, twist and curl before falling from the plant prematurely.

Stop seedling diseases
Soybeans are a magnet for seedling diseases and seed rot. That makes seedling disease management a top-priority issue for many producers, especially when planting conditions are cool and soybean prices are hot.

Root symptoms include rotted roots with deteriorated taproots and lateral roots. The root cortex shows light gray to brown discoloration; if soil moisture is high, sometimes bluish fungal colonies are present. These symptoms signal reduced water and nutrient uptake. Visit for more information on SDS scouting tips and management options, or contact your local DuPont Pioneer agronomist or Pioneer sales professional.