The 2011 wheat harvest is but a distant memory for many farmers, who are well on their way to planning the 2012 wheat crop. It is variety selection time, and Jim Shroyer, Extension agronomist for Kansas State University, says choosing the best wheat varieties requires due diligence, but there are four traits to keep in mind: adaptability, genetic variability, pest resistance and yield.
Farmers who plant several different varieties would be wise to choose varieties with different genetic background, in order to increase resistance to pests, and spread out maturity levels. The prevalence of stripe rust two years ago is a grim reminder at how important genetic diversity can be.
"The 2010 crop really got hurt by stripe rust, especially if varieties had Jagger in the background, and most of our varieties then did have Jagger in the background," Shroyer says. "That really sifted the susceptibility out. From that point on, we're seeing varieties that don't have as much Jagger in the background, or have no Jagger in the background."
Shroyer adds that studying the K-State Disease and Insect Resistance Ratings is critical, too. In 2011, barley yellow dwarf was the most prevalent wheat disease in Kansas, but each year is different. In 2010, it was stripe rust; in past years, speckled leaf blotch, leaf rust and wheat streak mosaic were challenges.
Finally, producers need to look at yield.
"You want something that yields well and consistently under diversity," Shroyer says. "Also, keep in mind that what's good for wheat, is also good for diseases. Be prepared to use a fungicide if necessary."
The agronomist says wheat farmers may want to use blends of multiple varieties of wheat in order to add disease resistance and complementation diversity. For example, a farmer may want to plant a variety with high yield potential, but is susceptible to stripe rust. To protect against stripe rust, blend that variety with another variety that contains stripe rust resistance. That way, if an outbreak of stripe rust were to occur, some of the yield potential of that field is protected.
"You try and mix and match because we don't have a perfect variety," he explains. "You try and match what the other one doesn't have."
Farmers can look at the 2011 Winter Wheat Performance Tests to learn which wheat varieties yielded the best in several K-State-sanctioned test plots throughout the state. The complete results are online at www.agronomy.ksu.edu/kscpt, or farmers may pick up a free copy of the 2011 Kansas Wheat Book from a local certified seed dealer or Extension office.
Another source of variety information is the "Know Your Wheat" book, published by the Kansas Wheat Commission and available at grain elevators or certified seed dealers throughout the state. The pocket-sized guide is free of charge.