By Scout Nelson
Warm and humid weather continues to increase disease pressure in Minnesota’s small grain crops, creating favorable conditions for several important diseases. Current disease models show that the risk of Fusarium head blight (FHB) has increased from low and moderate levels to moderate and high levels, depending on the variety’s resistance to the disease.
High dew points are expected to remain across much of the state for several days. These conditions create hot, muggy days and warm nights, allowing diseases to develop more easily. As a result, growers are encouraged to closely monitor crop development and make timely management decisions.
Disease risk information comes from both the national FHB forecasting model and the NDSU FHB risk model. While both indicate increased disease pressure, the national model often shows a higher risk because it uses weather forecasts and data from National Weather Service stations. The NDSU model uses weather information collected directly from nearby NDAWN and MAWN stations, providing more detailed local conditions. Since rainfall has been uneven across the state, local weather stations may provide a more accurate estimate of disease risk for nearby fields.
Farmers growing oats should apply a fungicide at the fully headed growth stage if a fungicide was not previously used to manage crown rust at the flag leaf stage. Fields that follow corn harvested for grain may benefit from a premium fungicide to help reduce FHB risk.
Spring barley growers are advised to apply a fungicide at the fully headed stage to suppress Fusarium head blight and manage net blotch, especially in susceptible varieties. Prosaro or a comparable product is recommended as a minimum treatment.
Spring wheat should receive a fungicide application at the beginning of anthesis to reduce the risk of Fusarium head blight. Premium fungicides may provide added protection in fields planted after corn or in varieties that are more susceptible to the disease.
Field scouts are also reporting an increase in Bacterial Leaf Streak (BLS). The appearance of this disease is expected because of current weather conditions and crop growth stages.
Photo Credit: gettyimages-sveta
Categories: Minnesota, Crops, Wheat, Weather