This proposal will address four focus areas:
1. Study of white mold epidemiology for improved management:
a. Determine conditions necessary for white mold spore release and when plants become infected to improve timing of foliar fungicides and management decisions such as irrigation
b. Validate and improve a disease forecasting model

2. Investigate the profitability of foliar fungicides:
a. Evaluate foliar fungicide and biological products and application timing for improved white mold management
b. Evaluate profitability of foliar fungicides in the absence of disease

3. Screen soybean germplasm for white mold resistance
a. Screening of promising WM resistant germplasm from University of Wisconsin
b. Facilitate screening of WM resistant lines from Dr. Dechun Wang

4. Provide white mold management education to growers and CCA’s

1. Study of white mold epidemiology for improved management:
The main objective of this study will be to improve knowledge of the timing for apothecia development and ascospores release in order to develop a predictive model and to determine optimal timing of fungicide application.
The specific objectives are:
• Determine the relationship between the apothecia germination and ascospores release and environmental variables (temperature and leaf wetness duration).
• Validate and improve Sporecaster a weather-based predictive model to improve soybean white mold understanding, forecasting and management.
Weather stations will be placed in soybean plots at the Montcalm research station, to determine the timing of spore release and the corresponding environmental conditions. We will also sample plants and take notes on plant stage development and flowering period to determine when plants are becoming infected.

2. Evaluate foliar fungicide and biological products and application timing for improved white mold management:
• Foliar fungicides and timings will be evaluated to determine optimal product and application timing relative to crop development.
• Investigate the profitability of foliar fungicides in the absence of disease
• Fungicide efficacy and profitability trials will be conducted at locations without known white mold pressure to determine the profitability of foliar fungicides in the absence of disease.

3. Screening of soybean germplasm for white mold resistance:
We will screen germplasm for University of Wisconsin-Madison and assist Dr. Wang’s lab in the set-up and screening of germplasm for white mold resistance.

4. Provide white mold management education to growers and CCA’s:
Information collected regarding timing and conditions of spore release and plant infection and optimized fungicide timing will be shared with state of Michigan growers and colleagues in the Midwest, to improve management of white mold. Dr. Damon Smith from the University of Wisconsin and I have been exchanging information and are establishing a collaboration to maximize our research efforts on white mold management. Data from these studies will be used to update regional extension publications.

Performance will be evaluated monthly through lab meetings, and through multistate meetings with collaborating institutions.

Updated September 23, 2020:
Improve Sporecaster
Objective: Improve the forecasting ability of Sporecaster
Working with colleagues at UW-Madison we are refining Sporecaster by conducting fungicide timing studies to provide additional year-site data sets to constantly improve the predictive model.

Screen foliar fungicides for the management of white mold
Objective: Screen new and old chemistries and biologicals for management of white mold
In this field based objective we are screening traditional new and old chemistries and biologicals for management of white mold for companies including Corteva, Gowan, Adama, etc. In addition to the company requested trials we conduct public trials to test standard products and those that we receive questions on, but for which there is little data such as foliar applied Ca and Mn and hydrogen peroxide.

Integrated management of white mold
Objective: Assess the impacts of fertility and plant population on white mold management
In this study we are examining varying rates of nitrogen fertility and plant populations for the effect on white mold development. The trials are designed around questions that farmers as us regarding the impacts of these agronomic variables on disease.

Variety screening of BASF/DFSeeds/Bayer/GDM varieties for white mold resistance
Objective: Screen commercial soybean lines for white mold resistance
Although no soybean varieties are completely resistant to white mold, a disease management plan should include the selection of varieties with good levels of partial resistance (field tolerance). In these trials we are screening pre-commercial or recently released varieties for white mold resistance.

Germplasm screening for white mold resistance
Objective: Work with the MSU soybean breeding program to screen germplasm for white mold resistance
We have planted and maintained plots at the Montcalm research center for the screening of Dechun Wang’s breeding material for white mold resistance

The impact of atrazine and Contans in the development of white mold
Objective: Assess the impact of atrazine and Contans on white mold development in soybeans
In this field trial at Montcalm we are working with Erin Burns to assess the possible role of atrazine in reducing the ability of the white mold fungus to produce viable spores. Within this same trial we are also assessing the efficacy of Contans for the reduction of white mold in soybeans through the management of the sclerotia resting body.

Research results will be distributed through field days, and extension meetings. A multi-state extension bulletin will be produced and made available through the Crop Protection Network (www.cropprotectionnetwork.org) and articles will be created for Michigan Soybean News and MSUE News for Ag. YouTube videos will also be created to report results, and social media such as Twitter and Facebook will be used to relay take-home messages to the Michigan agricultural community. Fungicide efficacy data is translated into national fungicide efficacy charts.