The researchers looked at Dominion, one of the more disease resistant varieties available to growers, compared to USG 3209, which is more susceptible to diseases like powdery mildew and fusarium head blight. Fungicides used were Quilt and Twinline, applied at three different growth stages of wheat, applied at growth stage 30 only, at GS 30 and flag-leaf, and at flag-leaf only.

“Any treatment that didn’t include flag-leaf application in the tests here at Rowland had more disease. Particularly in the more susceptible variety, you can see more rust and other diseases. Whether that translates into a yield difference, we won’t know until we harvest the crop,” Love says.

Fusarium head blight or head scab produces a toxin, vomitoxin, in the head of wheat. It has become an increasingly severe problem throughout the eastern U.S., says USDA-ARS Plant Pathologist Christina Cowger.

It is becoming increasingly clear, she says, that the primary reason for the increase in incidence of fusarium head blight (FHB) is the increasing popularity of no-till wheat production.

Specifically, no-till wheat often follows corn. That leaves more corn debris in the growth environment, which provides an ideal growth site for the spores that cause FHB, she explains.

Wheat is most susceptible to FHB at the flowering stage. When wheat flowers, spores come up from corn, wheat, barley or other debris on the ground and infect the wheat head. Infected wheat typically has two fairly distinct colors — part of the grain will be bleach white and light green.

“Once a kernel is infected, it shrinks, reducing test weight and subsequently, the value of wheat. If you see a wheat head with the whiter, bleached look, that is the vomitoxin that has formed from the infections,” she explains.

Cowger stresses the time to protect wheat from FHB is during flowering. Once the vomitoxin symptoms show up, it’s too late.

North Carolina State University Professor and Small Grains Breeder Paul Murphy showed attendees to the meeting results of small grain variety tests at the Shooter Farm. He gave an overview of each variety and how it performed in these tests in Southeastern North Carolina.

The field day was co-sponsored by the North Carolina State University College of Agriculture and Life Sciences and the North Carolina Small Grain Growers Association.

rroberson@farmpress.com