FHB risk has been high in southern Illinois since Monday. Early-planted and early-maturing wheat varieties in this region are at or near flowering. If susceptible varieties are flowering, a fungicide application may be needed to suppress FHB development. Growers should monitor fields closely and consult the FHB Risk Tool for ongoing updates.

--Boris X Camiletti, Assistant Professor, University of Illinois Urbana-Champaign

The risk of Fusarium head blight (FHB) has increased due to rains that have occurred over the last few days. Large differences in risk can be observed when choosing "Very Susceptible" to "Moderately Resistant" varieties in the FHB Risk Model. For susceptible varieties, a high risk of FHB can be observed across Kentucky, but for moderately-resistant varieties, the FHB risk is mostly low to medium, with a few spots under high risk. Wheat is generally now beyond the time where a fungicide application can be made (several days past early anthesis at this point in time), except for maybe a few exceptions with later-maturing wheat varieties. It will be important to start monitoring for symptoms of FHB in wheat fields over the next few weeks to determine if adjustments to combine fan speeds should be made, which can help blow out the lightweight "tombstone" kernels, which may have the highest levels of deoxynivalenol (DON; "vomitoxin").

--Dr. Carl A. Bradley, Professor and Extension Specialist, University of Kentucky

Wheat in southern Indian is starting to head out (Feekes 10.1), therefore it is time to monitor FHB risk to make an informed decision if a fungicide application is necessary.

The current and 2 day risk map is showing a medium to high risk (orange/red) for southern Indiana, but as we dry out the 6 day risk goes drops back to low (yellow) for the whole state.

A reminder that if you chose to apply a fungicide the triazole-containing fungicides are best for FHB– see the wheat fungicide efficacy tables for more information at http://doi.org/10.31274/cpn-20190620-031

--Dr. Darcy Telenko, Assistant Professor Extension Specialist, Purdue University

Wheat fields in Kentucky are currently at or fast approaching anthesis (Feekes growth stage 10.51). The risk of Fusarium head blight (FHB) across the state is currently low, but that could change with the forecast of possible rains this week. If the decision to apply a fungicide is made, it is important to use an effective fungicide. Research from the University of Kentucky has shown that several products provide good efficacy against FHB and contamination of grain by associated mycotoxins, such as deoxynivalenol (DON). For specific information about product efficacy, review the publication, "Fungicide Efficacy for Control" of Wheat Diseases available on the Crop Protection Network website (https://cropprotectionnetwork.org/).

--Dr. Carl A. Bradley, Professor and Extension Specialist, University of Kentucky

Wheat fields in Kentucky are now at anthesis (Feekes 10.51) or fast approaching it. Currently, most of the state is under “low risk” for FHB for susceptible to moderately resistant varieties; however, for very susceptible varieties, some areas are in a medium to high risk, with predictions of risk to increase over the next two days. For in-season management of FHB, it is important to apply a fungicide with efficacy against FHB. The most recent edition of the “Fungicide Efficacy for Control of Wheat Diseases” publication is available on the Crop Protection Network (https://cropprotectionnetwork.org/publications/fungicide-efficacy-for-c…), which provides information on efficacy of fungicides for control of FHB and other diseases. For FHB management with fungicides, it is important to apply at Feekes growth stage 10.51 up to about 6 days after for the greatest protection against FHB.

--Dr. Carl A. Bradley, Professor and Extension Specialist, University of Kentucky

Wheat was in the boot stage in southern Indiana last week, whereas in central Indian we are around Feekes 8 as the flag leaves are beginning to emerge. As wheat heads reach complete emergence it will be important to start watch for beginning flowering. Currently Fusarium head blight (FHB) risk is low for Indiana (4/22/24). It will be important to keep an eye on this map to make an informed decision to determine if fungicides for scab are needed once wheat starts to flower.

--Dr. Darcy Telenko, Assistant Professor Extension Specialist, Purdue University

Most wheat in Tennessee is in the flowering period, the highest period for susceptibility to scab/FHB infection. While risk is estimated to be low for 'susceptible varieties', those using very old varieties should change the model to 'very susceptible' and consider the higher risk. Similarly, the scattered showers within the 10-day window recently will increase risk and might not be captured in the model. Consider protecting wheat from scab/FHB and use the fungicide efficacy table to chose the right product for your situation -https://cropprotectionnetwork.s3.amazonaws.com/cpn3002_fungicideefficac…

--Heather Marie Kelly, Extension Plant Pathologist, University of Tennessee-Entomology & Plant Pathology

Flowering continues in wheat this week across the northern half of the state of Ohio. This is the growth stage as which the crop is most susceptible to infection by Fusarium graminearum, the fungus that cases Fusarium head blight (FHB), also known as head scab. Consequently, questions are being asked about applying a fungicide to control FHB and minimize grain contamination with mycotoxins. However, according to the FHB forecasting system, the risk for head scab development has been low across the state over the past week. This is likely due, at least in part, to the cool, relatively dry conditions we have experienced in most area. The extended forecast suggests that dry (rain-free) conditions will persist over the next week or so. Remember, warm and consistently wet or humid conditions are required for FHB to develop. So, do continue to monitor the weather and use the scab forecasting system to determine if the risk for scab is increasing at the crop flowers in northern, late-plante d fields.

--Pierce Anderson Paul, Extension Plant Pathologist, The Ohio State University

Wheat in southern Indiana has started to head out and will probably start flowering (Feekes 10.5.1) in the next week. Currently the six day forecast for FHB is low for most of the state, but rain is predicted again next week. In central Indiana our wheat is at flag leaf (Feekes 9).

Wheat will be susceptible to FHB infection as it moves into early anthesis through full flower. A fungicide application may provide protection during this critical time. The updated wheat fungicide efficacy guide is a resource that can provide guidance on fungicide choice for efficacy against FHB and other diseases. It is available on the Crop Protection Network at https://cropprotectionnetwork.org/publications/fungicide-efficacy-for-c…. Continue to monitor the risk as weather changes over the next few weeks to see what happens as the rest of the state moves into that critical time period.

--Dr. Darcy Telenko, Assistant Professor Extension Specialist, Purdue University

Many wheat fields will begin going through early anthesis (flowering; Feekes growth stage 10.51) this week in Kentucky. Although rain occurred in some areas of Kentucky over the last few days, the chances for precipitation over the next few days are relatively low. Wheat continues to be susceptible to infection by the FHB pathogen beyond early anthesis, so it is important to consider making a fungicide application at Feekes 10.51 to provide protection during this critical time. The wheat fungicide efficacy guide on the Crop Protection Network (www.cropprotectionnetwork.com) provides information about which fungicide products provide the greatest efficacy against FHB and other important diseases.

--Dr. Carl A. Bradley, Professor and Extension Specialist, University of Kentucky