2019
Survey and Baseline Fungicide Sensitivities of Fungal Pathogens in Mid-Atlantic Soybean Production
Home
Contributor/Checkoff:
Delaware Soybean Board
Category:
Sustainable Production
Keywords:
Crop protectionDiseaseField management
Parent Project:
This is the first year of this project.
Lead Principal Investigator:
Alyssa Koehler, University of Delaware
Co-Principal Investigators:
Project Code:
Contributing Organization (Checkoff):
Delaware Soybean Board
$8,185
Institution Funded:
University of Delaware
$8,185
Brief Project Summary:

Correctly identifying soybean diseases is the first step in making sound management decisions to protect yield and quality. Many soil-borne pathogens can be present in a field, but they only attack when environmental conditions are favorable. While infection often takes place early in the season, symptoms don’t usually appear until soybeans enter reproductive growth stages. This survey characterizes the most common fungal pathogens in the Mid-Atlantic. It identifies threats and develops management recommendations for common disease pressure in soybeans. Understanding what is most likely to be in fields under various weather conditions allows soybean farmers to make better decisions to optimize yield and quality.

Key Benefactors:
farmers, agronomists, Extension agents

Information And Results
Final Project Results

Updated March 31, 2020:

View uploaded report PDF file

Soilborne pathogens can reduce soybean yield and quality. Limited research has been conducted in recent years to characterize and identify problematic fungal pathogens to species. Project objectives included: (1) Characterize fungal pathogens in Mid-Atlantic conventional and organic soybean production and observe the frequency of isolation across farms. (2) Build a collection of isolates that can be screened for fungicide sensitivity and used in other projects to verify pathogen species using molecular protocols. (3) Identify locations with high disease pressure that may be used for future research and demonstration plots. In 2019, sixty field sites were surveyed. Soilborne fungal pathogens were isolated from 40% of sampled fields. Three species of the fungus Diaporthe were isolated from stem and root tissue across 17% of fields, along with Macrophomina phaseolina, the causal agent of charcoal rot, isolated from 17% of fields. A subset of twenty-six isolates were selected for in-vitro fungicide efficacy to three fungicides. All fungi screened were sensitive to all products with ED50 values ranging from <0.01 – 2.4 ppm. From this trial, a field was identified that will be used for soybean seed treatment efficacy trials in 2020, other field sites with Diaporthe species present were identified for continued survey work in 2020.

The United Soybean Research Retention policy will display final reports with the project once completed but working files will be purged after three years. And financial information after seven years. All pertinent information is in the final report or if you want more information, please contact the project lead at your state soybean organization or principal investigator listed on the project.