Database Research SummariesDeveloping an integrated management and communication plan for soybean SDS
Research Focus
The foundational management strategy for sudden death syndrome (SDS) is using resistant cultivars. However, in years when environmental conditions are especially favorable for disease development, host resistance alone does not provide adequate control. Also, SDS continues to move into new areas. The main goal of this project is to investigate management options that will help ensure resistant cultivars will be as effective as possible even in unusually conducive conditions for SDS to develop.
Objectives
- Determine how fungicides and nematicide seed treatment, in-furrow, and foliar fungicides will affect SDS and soybean cyst nematode (SCN)
- Field evaluation of integrated management of sudden death syndrome and understanding their effect on populations of the SDS pathogen, Fusarium virguliforme, and soil health
- Develop models to quantify the negative yield impacts of SDS foliar symptoms and root rot
- Study genetic and virulent variability of Fusarium virguliforme using differential soybean varieties and resistance mapping for foliar chlorosis and necrosis of sudden death syndrome
- Communicate research results with farmers, agribusinesses and other soybean stakeholders
Results
- In a two year study on the effect of seed treatment and foliar crop protection products on SDS and yield of soybean, planting resistant cultivars and using fluopyram seed treatment were the most effective tools for SDS management. Of all the products tested, fluopyram had the highest efficacy, but plant resistance provided an overall better yield advantage than using fluopyram seed treatment alone.
- The relationship between SDS and soybean yield is being established. Using data from 57 uniform field experiments conducted in Illinois, Indiana, Iowa, Michigan, Wisconsin, and Ontario, Canada from 2013 to 2017, we found a negative correlation between FDX (mean foliar disease index—a measure of SDS severity) and yield. The correlation was affected by disease level and soybean variety with a greater effect in higher disease levels and with SDS-susceptible varieties. Currently, we estimate that for every unit of FDX increase, yield will be decreased by 0.5%.
- In a two year study on the effect of seed treatment and foliar crop protection products on SDS and yield of soybean, planting resistant cultivars and using fluopyram seed treatment were the most effective tools for SDS management. Plant resistance provided an overall better yield advantage than using fluopyram seed treatment alone. Of all the products tested, fluopyram had the highest efficacy.
- The relationship between SDS and soybean yield is being established. Using data from 57 uniform field experiments conducted in Illinois, Indiana, Iowa, Michigan, Wisconsin, and Ontario, Canada from 2013 to 2017, we found a negative correlation between FDX (mean foliar disease index—a measure of the SDS severity) and yield. The correlation was affected by disease level and soybean variety with a greater effect in higher disease levels and with SDS-susceptible varieties. Currently, we estimate that for every unit of FDX increase, yield will be decreased by 0.5%.
- In a two-year study to determine the interaction between the fluopyram (IleVO) seed treatment and pre-emergence herbicide in Iowa and Indiana, it was observed that seed treated with ILeVO resulted in higher phytotoxicity at VC-V1 than seed without ILeVO, regardless of preemergence herbicide treatment. The combination of preemergence herbicide and ILeVO did not increase the severity of soybean injury in any year or location compared to either applied alone.
- From our previous SDS management project, we identified the most effective quantitative PCR technique for identifying Fusarium virguliforme in soybean plants and in soil. This is an important development that enables the evaluation of direct effects of management practices on the SDS pathogen in the field and in soybean plants.
- A manuscript entitled “Multi-location evaluation of fluopyram seed treatment and cultivar on root infection by Fusarium virguliforme, foliar symptom development, and yield of soybean” has been published in the Canadian Journal of Plant Pathology.
- A manuscript entitled “Predicting soybean yield and sudden death syndrome development using at-planting risk factors” has been published in the journal Plant Disease. The aim of this study was to develop models to predict SDS severity and soybean yield loss using at-planting risk factors to integrate with current SDS management strategies. The models indicate that it is possible to predict patches of SDS severity using at-planting risk factors. Verifying these models and incorporating additional data types may help improve SDS management and forecast soybean markets in response to SDS threats.
- We completed field experiments in Iowa, Indiana, Michigan, Wisconsin and Ontario, Canada to investigate the effect of corn residue on SDS development. We compared two levels of residue removals and two tillage systems in corn and soybean rotation system. We recorded data on plant population, root rot, foliar SDS, and yield. We are analyzing the data and summarizing the results.
Importance
- The project has a direct benefit to soybean farmers by providing evaluations of current and future crop production practices and products.
- Farmers will benefit from management strategies that enhance the effectiveness of SDS-resistant soybean varieties.
- An integrated SDS management program will reducing economic losses to producers through better management of SDS.
For more information about this research project, please visit the National Soybean Checkoff Research Database.
Funded in part by the soybean checkoff.
