Although field history is a good indication of the types of disease problems that may be found in a field, weather plays a critical part in whether certain diseases will be expressed in any given year. As with management of other pests, many areas of crop production need to be incorporated for the best opportunity to reduce disease pressure.
Crop rotation away from legumes, such as soybeans, can help to reduce disease potential. Select varieties with resistance to diseases that would most likely be encountered. From there, make sure a seed treatment is used, which will help protect yields.
For soilborne disease problems, try a pre-dawn spray, especially at the 75 days after planting mark. Research has shown that early morning sprays improve coverage and therefore, improve white mold control.
For leaf spot management, allow the fungicide product to stay on the leaf for 48 hours, if possible. Compensate for wet weather by shortening the spray interval. Weigh the cost of the fungicide with the efficacy provided, and initiate the spray program based on planting date and efficacy of the fungicide.