Predicted Risk for Head Scab Continues to be Low Across Ohio. Although it has rained over the last few days, temperatures have dropped into the upper 50s and lower 60s, with nighttime temperatures in the mid-to-upper 40s in some places. Cold temperatures between anthesis and early grain fill usually reduce the risk for scab, as the disease develops best under warm, wet, or humid conditions. However, do keep your eyes on the weather and the forecasting system as the crop continues to go through the anthesis growth stage over the next few days, particularly in the northern third of the state. The forecast is for warmer temperatures and isolated showers over the Memorial Day weekend and into next week (the week of May 31). Late-developing fields may still be at risk for head scab as temperatures increase, particularly if it stays wet and humid. You may need to consider applying Prosaro, Caramba, or Miravis Ace, but remember, these fungicides are most effective against head scab when th ey are applied at or a few days after anthesis.

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

Several wheat fields in Kentucky currently are at the early anthesis stage (Feekes growth stage 10.51) or beyond that stage. Currently, the FHB risk map is showing a medium risk for FHB in some areas of Kentucky. With rainfall in the forecast in the upcoming days, this risk may increase and encompass a larger geography. Because of rainfall, soil is saturated in several fields, making it difficult for ground sprayers to apply fungicides. It is important to note that multi-state research trials have shown that effective fungicides registered for FHB control in wheat have been effective in reducing FHB and the associated mycotoxin DON when applied up to 7 days after the early anthesis stage. Please read all fungicide labels before making any applications to ensure that your crop is still at a stage where fungicides can be applied.

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

Wheat in the Northern part of the state has started to flower this week, whereas wheat in the central part of the state has just finished flowering. Warm, wet weather will continue to elevate FHB risk in flowering wheat, and a fungicide application of Caramba, Prosaro, Proline, or Miravis Ace are suggested at this time. Applications are most efficacious when made following label directions between the start of flowering and 5 days after this point in time. Flowering is defined as the point in time when 50% of main tillers have started to push anthers. Do not apply products containing strobilurins for FHB management.

Wheat in the southern part of the state should now be showing symptoms and signs of FHB if severe infection occurred (bleached heads/portions or heads/spikelets with salmon colored growth). Recent surveys indicate that overall FHB levels are likely low in this part of the state. The central part of Illinois however, was under high risk across wheat resistance levels during the critical flowering period and should be monitored closely over the coming days. Symptoms of FHB will be most observable 18-24 days after flowering. If severe FHB is detected, you should be prepared to take measures to remove contaminated grain. These include increasing combine fan speeds and openings to blow out lightweight, FHB-infested grain, harvesting infected fields as early as possible (and preferably first) and if possible, storing grain from infested fields separately from quality grain. Ensure that grain is dried (15% optimal) to minimize continued growth of pathogen and DON accumulation in storage.

-- Nathan Kleczewski Ph.D., University of Illinois, Research Assistant Professor and Extension Specialist

For more details, go to the FHB Risk assessment tool at http://www.wheatscab.psu.edu

For the latest news and updates from the U.S. Wheat & Barley Scab Initiative, go to https://www.scabusa.org

 

According to the head scab forecasting system (http://www.wheatscab.psu.edu/), the risk for head scab, and consequently , vomitoxin contamination of grain is current high across the state for wheat flowering today. I fact, the risk for scab has been high throughout the week due to the fact that it has been wet and warm. Most of the wheat in northern OH it either at or will soon be at the critical anthesis or flowering growth stage when infection by the scab fungus typically occurs. There is more rain and warm weather in the forecast, meaning that the risk will likely continue to be high as more fields in the northern third of the state reach anthesis. Plan to apply either Prosaro, Caramba, or Miravis Ace at or within the first 4-5 days after anthesis. This will reduce scab and vomitoxin by 50% of more.

Click on the link below to learn how to interpret the foresting system and identify the anthesis growth stage. https://agcrops.osu.edu/newsletter/corn-newsletter/2020-15/using-forecas...
--Pierce Paul, Extension Plant Pathologist, Ohio State University
For more details, go to the FHB Risk assessment tool at http://www.wheatscab.psu.edu
For the latest news and updates from the U.S. Wheat & Barley Scab Initiative, go to http://www.scabusa.org

High scab risk is predicted for all wheat of all resistance levels across much of the state according to the current risk model. Additionally, many varieties are moving into flowering or are currently flowering in much of the state with high risk. Now is the time to consider a fungicide application for fields that are flowering or are soon to be. With rains predicted in the coming days, it is important to remember that the optimal time for a fungicide application is at or within 5 days of flowering, so find the window to apply an effective triazole or triazole + SDHI fungicide when possible. Be sure to keep in mind the rainfast period when applying during these windows. DO NOT apply a strobilurin-containing fungicide as these fungicides can increase mycotoxin levels in the grain. Always read and follow label instructions when applying fungicides.

-- Kaitlyn Bissonnette, University of Missouri, State Field Crop Plant Pathologist

For more details, go to the FHB Risk assessment tool at http://www.wheatscab.psu.edu

For the latest news and updates from the U.S. Wheat & Barley Scab Initiative, go to https://www.scabusa.org

Wheat in the southern part of Illinois is currently flowering to past flowering. Wheat in the central part of the state is approaching heading in many fields. With warmer temperatures forecast I expect many fields in the central part of the state to flower next week. Rains are forecast during this time as well, which may elevate risk for FHB in wheat flowering during this period. Replicated research indicates all suggested fungicides for suppressing FHB are most efficacious in suppressing vomitoxin when applied between FGS 10.5.1 through 5 days after 10.5.1. FGS 10.5.1 is defined as the point where 50% of the main tillers have started to flower in a field. Symptoms of FHB are typically most pronounced 18-24 days after flowering.

Suggested fungicide products for suppressing FHB and vomitoxin include Prosaro, Caramba, Miravis Ace, and Proline (if following with vegetables). Ensure that all label directions are being followed to ensure proper application and to ensure optimal performance. Do not apply fungicides that contain a strobilurin (FRAC group 11) as these have been associated with enhanced DON in replicated research trials. Continue to monitor your fields and the FHB prediction center as you approach the most critical times for applying in season fungicides for FHB.

-- Nathan Kleczewski Ph.D., University of Illinois, Research Assistant Professor and Extension Specialist

For more details, go to the FHB Risk assessment tool at http://www.wheatscab.psu.edu

For the latest news and updates from the U.S. Wheat & Barley Scab Initiative, go to https://www.scabusa.org

Early planted wheat has started to flower in the southern part of Illinois. Although conditions have been cool, persistent rains continue to elevate levels of FHB risk in flowering, highly susceptible wheat varieties. Suggested fungicide products for suppressing FHB and vomitoxin include Prosaro, Caramba, Miravis Ace, and Proline (if following with vegetables). Replicated research indicates all of the suggested products are most efficacious in suppressing vomitoxin when applied between FGS 10.5.1 through 5 days after 10.5.1. FGS 10.5.1 is defined as the point where 50% of the main tillers have started to flower in a field. Ensure that all label directions are being followed to ensure proper application and to ensure performance. Do not apply fungicides that contain a strobilurin (FRAC group 11) as these have been associated with enhanced DON in replicated research trials. Continue to monitor your fields and the FHB prediction center as you approach the most critical times for applying in season fungicides for FHB.

-- Nathan Kleczewski Ph.D., University of Illinois, Research Assistant Professor and Extension Specialist

For more details, go to the FHB Risk assessment tool at http://www.wheatscab.psu.edu

For the latest news and updates from the U.S. Wheat & Barley Scab Initiative, go to https://www.scabusa.org

Wheat has begun flowering in the southeast region of the state and is moving full on into heading in the rest of the southern part of the state. Overall risk for FHB development remains low for most varieties that fall in the Moderately Susceptible and Moderately Resistant categories. As wheat starts to head out and flower in the rest of the state in the coming weeks, there are a few things to consider when determining whether a fungicide application will be warranted in your field. Consider the resistance level of the variety, the weather conditions present, and if wheat is flowering or approaching the flowering stage. If considering a fungicide application, the optimal time to apply a fungicide at or within 5 days of flowering. It is not recommended to apply a strobilurin containing fungicide as these fungicides can result in increases in mycotoxins in the grain. Always read and follow label instructions when applying fungicides.

-- Kaitlyn Bissonnette, University of Missouri, State Field Crop Plant Pathologist

For more details, go to the FHB Risk assessment tool at http://www.wheatscab.psu.edu

For the latest news and updates from the U.S. Wheat & Barley Scab Initiative, go to https://www.scabusa.org

Illinois FHB update. Nathan Kleczewski Field Crop Plant Pathologist, UIUC

Some of the earlier planted wheat in the southern portions of the state may be heading by the end of this week. After heads have cleared the ligule, you generally have 3-5 days before the start of flowering (Feekes growth stage (FGS) 10.5.1.). Forecasts are not calling for significant rain over the next 10 days as of today (4/28), and the current risk for moderately susceptible wheat heading into flowering within the next 3-5 days should remain low. Continue to scout fields and monitor this site for updates as your wheat in these areas enter the critical period for FHB. If considering a fungicide, suggested products include Prosaro, Caramba, Miravis Ace, and Proline (if following with vegetables). Replicated research indicates all of the suggested products are most efficacious in suppressing DON when applied between FGS 10.5.1 through 5 days after 10.5.1. FGS 10.5.1 is defined as the point where 50% of the main tillers have started to flower.

--Nathan Kleczewski Ph.D., Research Assistant Professor and Extension Specialist

For more details, go to the FHB Risk assessment tool at http://www.wheatscab.psu.edu

For the latest news and updates from the U.S. Wheat & Barley Scab Initiative, go to https://www.scabusa.org