Choosing the right variety for specific uses and conditions may be the most important decision a wheat farmer makes, and it’s a chore that requires yearly analyses of new offerings, changes in resistance packages and intended crop use.
“Yield stability is a key factor,” said Robert Duncan, Texas AgriLife Extension small grains specialist at the recent Big Country Wheat Conference in Abilene.
“Consider multiple years of yield data and evaluate varieties at multiple locations,” Duncan said. “Weigh limiting factors for each variety at each location.”
He said wheat producers should always consider the pest resistance package of any variety they consider. “That includes both disease and insect pests.”
He said final use also merits attention. Growers may select a different variety if they are producing for grain only than they would if they intend to graze the wheat. Another variety might be better suited for dual-purpose wheat, grazing for several months and then finishing the crop for grain.
Duncan said growers should look at older varieties in relation to recently released ones to see how they compare.
In 2010 Rolling Plains variety trials, top three yields came from Duster, 54.4 bushels per acre; Billings, 53.7 bushels per acre; and Greer, 53.1 bushels per acre.
“But look at the three year average yields,” he said. “Some varieties that did not make the top tier in 2010 have excellent three-year yield averages.”
He said several varieties remained in the top tier in most trials. Duster, for instance, was in the top group in seven of eight trials. CJ was in the top six out of eight times and Greer, Tam 203, and Doans were in that top group in five out of eight trials, while Fannin and Billings also performed well.
Duncan said growers also must be aware of changes in pest populations when selecting a variety.
“We had a new race of stripe rust in 2010,” he said, “that affected varieties that had been previously resistant.”
In addition to cultural management practices, he said growers have two options to control diseases—selecting resistant varieties or applying fungicides.
In years with no significant disease pressure, applying fungicides to susceptible varieties had no measurable effect on yield.
“But with high disease pressure, along with a susceptible variety, we saw a significant yield increase from a fungicide application. With a resistant variety, such as Fannin, we saw no significant advantage by applying a fungicide. Even with three applications on Fannin, we see no significant advantage.”
Treating susceptible varieties during periods of high disease pressure may increase yield as much as 20 bushels per acre or more.
Duncan said a fungicide such as tebuconazole, which has been highly effective, may cost as little as $5 per acre, plus the application cost.
He said in some locations, wheat farmers also may consider varieties tolerant to Hessian fly and other insect pests.