"Wheat's" your plan for FHB?

Fusarium Head Blight (FHB) or Head Scab is a disease that can have a great impact on your wheat. Headscab is caused by the fungus Fusarium spp. The fungus overwinters in corn and small grain residue. The infection route is primarily through the flowers with outbreaks being most frequent in humid or rainy weather during early blooming stage (Feekes 10.5.1) through early dough stage (Feekes 11.2). What makes this disease so important is because when prevalent, a mycotoxin called deoxynivalenol (DON) is produced causing poor seed quality and reduced grain value. Livestock, especially swine, are sensitive to DON-contaminated grain. The USDA limits DON levels to 5 ppm for livestock consumption and 1 ppm for wheat used for human consumption. Below you can see the effects in feeding pigs grain with higher DON (Pig B) compared to low-no DON. Because of this, protecting the flowers is key to head scab suppression and DON reduction. Right now, the wheat crop is ranging between Feekes 6 (jointing) and 8 (flag leaf emergence), across the state and we are swiftly reaching optimal Headscab application of early flowering (Feekes 10.5.1). Another tool to help determine risk oh Headscab can e found at http://www.wheatscab.psu.edu/ . Using local data weather data, researchers have developed a FHB predictive model for disease outbreak, which you can follow to see the latest news and predictions. Below is a snapshot from http://www.wheatscab.psu.edu/ taken today on May 7th. The model was set to very susceptible winter wheat and given the current weather conditions and parameters used, most of Ohio is at a moderate to high risk for FHB infection. You can change the parameters to fit your wheat crop better and gain an insight into risk you might be facing and to help you make management decisions. If you’re wanting to protect your wheat crop this season, applying Caramba® fungicide at Feekes 10.5.1 or early flowering is the most effective way to reduce DON levels and achieve suppression of FHB. To get a better idea of when this might be; Once wheat reaches Feekes 9 (flag leaf fully emerged) it will typically flower 9-16 days later. When 75% of the heads have fully emerged, call this day 0 and plan your Caramba applications between Day 2 and Day 8. Remember, when making your Caramba application that timing is critical when it comes to effectively managing FHB and the infections set in when anthers are exposed during flowering. Also, to maximize your application coverage will be crucial, forward/backward nozzles or bi-directional nozzles that produce
fine to medium droplets are excellent. The high yield potential and risk of disease in this years’ wheat crop make it worth protecting. If you haven’t already, plan your Caramba application today!