By Anne Dorrance and Clifton Martin, Ohio State University Extension
The Ohio State University Soybean pathology lab evaluated a number of different components of soybean production this past summer for Ohio producers. Among the research efforts was some work with sudden death syndrome (SDS).
This fungal pathogen infects roots early in the growing season during wet conditions. However, symptom development does not typically occur until the plant reaches the end of its reproductive phase, unless inoculum levels are high, and weather is especially favorable.
This past season we planted a set of lines that were identified in Illinois as susceptible, moderately susceptible, resistant and highly resistant to this fungus. The location used also has soybean cyst nematode, which is another key pathogen that when SCN and the SDS fungus are both present, symptoms of SDS become well developed. Symptoms of SDS developed prior to flowering this year in the field. This was due to the continued heavy rains shortly after planting. Areas of the field with very high populations of SCN were stunted.
Each of the lines developed symptoms of SDS similar to the resistance score for what has been reported from other studies. Within the north central soybean research program, there is a team that evaluates germplasm annually for resistance to SDS. The results of these studies indicate that we can readily use the results from the Illinois trials to make decisions here in Ohio.