Lahoma Field Day brings wheat growers together for crop update 

On May 16, wheat growers and industry professionals gathered for the annual Lahoma Wheat Field Day, held at the Oklahoma State University North Central Research Station in Lahoma, Oklahoma. Attendees visited the wheat plots, heard from several speakers on topics such as disease, research on late planted wheat, wheat breeding improvements, herbicide injury symptomology, and wheat herbicide trait stewardship. 

Wheat disease update

Meriem Aoun, OSU small grains pathologist, gave an update on the diseases identified in the 2025 wheat crop. She said in March, soil-borne wheat mosaic virus was found, but it has not been a significant problem as most of the varieties planted in the state are resistant to the virus. Later in April, a severe infection of wheat streak mosaic virus was detected.  

“It’s unusual to see wheat streak mosaic virus widespread in so many locations,” Aoun said. “We usually see it in the Panhandle, but this year, it was in more than 17 Oklahoma counties.” 

Aoun said the best management technique to control WSMV is to control volunteer wheat and grassy weeds in fields at least 15 days prior to planting. Stripe and leaf rust have also been reported in the wheat crop, but Aoun said the cases are minimal and should not have much of an effect on yield. 

Fusarium head blight or head scab, is not a common disease found in Oklahoma, but the weather conditions this year made it one of the most prominent diseases found in this wheat crop. The end of April and the first two weeks of May produced record levels of rainfall and humidity—prime conditions for the development of fungal diseases. The risks for the disease were elevated during that time span because the moisture came during the time of flowering.  

“Fusarium head blight or head scab is not usually a problem for us in Oklahoma, except for growers that are in the eastern part of the state,” Aoun said. “This is because they rotate with corn, and corn is a host for fusarium, so that’s why they can see it more often.” 

The increased moisture, not normally found in the western part of the state, plus the lack of head blight resistant varieties planted, left the rest of the state open to increased disease susceptibility. Aoun said indications of fusarium head blight include pink or salmon-colored wheat heads. She said there are sporadic areas of infection in the crop but hopes it will not be a significant drag on yield. 

Leaf spotting diseases—including tan spot, septoria nodorum blotch, septoria tritici blotch, and spot blotch—are also a concern. Aoun said tan spot and septoria tritici blotch are usually found on the lower canopy. Indications of septoria tritici blotch are small, black structures on the lesions. Septoria nodorum blotch presents itself as small, dark brown to chocolate-colored lesions on the lower leaves. Eventually the lesions will develop a yellow halo around them and expand. 

Wheat breeding advancements

Brett Carver, OSU wheat breeding specialist, discussed the priorities for the university’s wheat breeding program and traits he is planning to breed for in the next varieties to be released. One trait he is looking to improve is resistance to wheat streak mosaic, which has been notably present across Kansas’ wheat crop and in parts of Oklahoma. 

“We were blessed with, so to speak, wheat streak mosaic.” Carver explained. “We were blessed in the way that we had it all over the state, and I had many opportunities as a plant breeder to go out and evaluate our material. I had never had this opportunity before.”  

Carver compared this disease presence and evaluation opportunity to the stripe rust epidemic of 2002. He said after studying the disease outbreak and past wheat breeding and genetics, he realized the tolerance bred into OSU’s wheat varieties goes back to Jagger, which is a Kansas State University hard red winter wheat variety released in 1994. 

Although the original Jagger variety may not be suitable for all Oklahoma environments—the Panhandle, in particular—Carver said the resistance that can be obtained using the Jagger line can help improve future wheat breeding to protect again the disease and develop varieties suitable for Oklahoma. 

“We’re using that information to groom the program in that direction for more wheat streak tolerance,” he explained. “We’re trying to make sure this doesn’t happen again down the road. Because, you know, if given this opportunity to shift our program in a certain direction, we need to take it.” 

Another bullet point of Carver’s presentation was the need for improvements in the CoAXium genetic lines. Carver expressed some urgency on the need to make some decisions for CoAXium breeding in OSU varieties.  

“In the CoAXium genetics, we lack a little bit of that disease resistance,” he said. “Thanks to the donor we used, we have some wheat streak resistance, and thanks to some of the genetics we have ourselves, we have some pretty good wheat streak tolerance in that germplasm. What I think we’re lacking is some leaf rust resistance. Stripe rust was good. We took care of that last year. Right now, it’s leaf rust.” 

Carver said although there are several CoAXium varieties that could be released, he plans to be vigilant in which ones and how many he releases, saying he does not plan to commercialize any more than one or two of those varieties.  

Carver also discussed the progression of OSU’s soft wheat varieties and their demand within the baking industry. 

“This is all about making wheat marketable,” Carver said. “With soft wheat, I’ve always felt like maybe we should be servicing that part of our clientele in the state, and they need to be serviced by Oklahoma State, so we’re going to do that through the commodity system.” 

Carver used the example of Double Stop and Strad varieties with soft endosperms as possible starting points for developing improved soft wheat varieties for Oklahoma.  

“We can breed a soft wheat with strong gluten,” he explained. “That is not a problem with us, because we have strong gluten in our hard wheats, so we change a couple of genes, and we’re there. We just need to find something that’s adapted, and we have it. So, we are going to make those changes and see where we can go with this.” 

Lacey Vilhauer can be reached at 620-227-1871 or [email protected].

Photo: Brett Carver, OSU wheat breeding specialist. (Journal photo by Lacey Vilhauer.)