By STEVE BINDER
Illinois Correspondent

MT. VERNON, Ill. — While wetter than usual conditions are keeping full-scale corn planting at bay in most of the Midwest, scientists say the excess rain may pose a significant risk to wheat crops in parts of Illinois.

Plant pathologist Carl Bradley, with the University of Illinois extension, said almost all of southern Illinois has been categorized as being at medium to high risk of the scab disease Fusarium head blight (FHB).

“FHB can cause both yield and quality losses. Quality losses can be due to lower test weights and contamination of grain by toxins produced by the fungus that causes FHB,” Bradley explained. “Because the fungal pathogen that causes Fusarium head blight, Fusarium graminearum, also causes Gibberella stalk and ear rot of corn, the pathogen is almost always present throughout Illinois surviving on corn debris.”

Wheat fields at risk are those that have headed out and are flowering, and a large portion of fields in Illinois will be in that state starting this week. Federal officials listed most of the region in the medium to high risk category April 27, using the FHB risk assessment tool available at www.wheatscab.psu.edu
UoI officials say farmers should act quickly. “For fields that will be flowering, a foliar fungicide for suppression of FHB and the associated mycotoxin deoxynivalenol (DON) is recommended for fields in the medium-to-high risk areas,” Bradley said.

“The only fungicides that are effective in providing respectable levels of FHB and DON suppression are Caramba, Prosaro and Folicur (and other tebuconazole products).”

Bradley explained foliar fungicides are the only “in-season” control option for FHB and DON; however, one of the best management practices for FHB and DON is choosing to plant a variety with a moderate level of FHB resistance. Planting a moderately resistant variety and spraying a foliar fungicide, if needed, will provide the highest level of FHB and DON suppression.
The best medicine right now, though, would be a good dose of sunshine and drier conditions.

“For fields that will be flowering next week, it is important to monitor the FHB risk assessment tool,” he said. “If the rain stops and sunny and dry conditions occur next week, then the risk of FHB will decrease.”
To sign up for “FHB Alerts” that can be emailed or sent as a text message to a mobile phone, go to http://scabusa.org/fhb_alert.php