ALBIN, Wyoming — Producers in Eastern Wyoming got the skinny on crop trial results, Wheat Streak Mosaic Virus, and got information on varieties of wheat that are performing during a Wheat Planning Decision Meeting at the Albin Community Center on Monday, Aug. 14.
Presentations about the 2017 Wyoming On-Farm Variety Trials were given by Keith Kennedy, executive director of the Wyoming Wheat Marketing Commission, and Carrie Eberle, assistant professor of Agronomy and Cropping Systems at University of Wyoming’s SAREC in Lingle,
“The Wheat Streak Mosaic was bad enough in Kansas this year that there were a bunch of growers talking about making volunteer wheat a noxious weed,” Kennedy said. “That’s how bad it was.”
Kennedy said that one location in Wyoming was sampled and tested by Montana State University, and returned positive for Wheat Streak Mosaic, Triticum Mosaic, and the High Plains Virus.
“There are some varieties out there that have some tolerance to Wheat Streak Mosaic virus, but the bad news is there are none that have a resistance to High Plains,” he said. “There is only one that has resistance to both Wheat Streak and Tirticum. The only wheat that we know of anywhere on the market that has that is Mace, which Nebraska introduced 15 or 16 years ago, and if you don’t mind something that yields 50 percent less than anything else, it’s a fine wheat.”
Kennedy said that most of the viruses are vectored by the wheat curl mite, which will infest vulnerable plants from volunteer wheat, to stands where there has been hail damage.
“Ideally you will have dry dead around the field you plant for at least two weeks before you plant,” he said. “Second, the later you plant, the less problem there’s going to be.”
A warm fall last year made it possible for the mites to breed and reproduce in order to spread the virus.
A Kansas State bulletin contained a chart that showed that a number of high-risk plants need to be controlled to avoid Wheat Streak.
“Some producers on the I-70 corridor in Colorado I’ve spoke to have fought Wheat Streak for years, especially as they plant dryland corn adjacent to their wheat,” Kennedy said. “They have an advantage because they start planting two to three weeks later than we are, but they actually go in and desiccate 50- to 60-foot strips adjacent to where they’re going to plant wheat. Even though corn is relatively low risk, if there are mites there, they will move over to fresh wheat.”
Kennedy said that two varieties, Avery and Langin from PlainsGold, have shown some potential resistance to curl mites in individual test strips, but it remains to be seen if it will hold up when planted on a whole field.
“Long term, that’s our best chance to find some solution in the wheat is some tolerance or avoidance by the mite, rather than going after all three of those viruses,” he said. “The chances that they will come up with something in the next 10 to 15 years for all three of those viruses are slim and none.”
Spur, a hard red winter wheat variety developed by the Montana Agricultural Experiment Station and released under license to CRFW in Wyoming, and Sygenta in the remainder of the U.S. has proved resistant to strip rust so far. It’s solid stem attribute has also proven to have some sawfly tolerance, and while tests in Montana have shown Spur is still susceptible to rust, Kennedy said that the sources are different. Montana’s rust comes in from the Pacific coast in Washington, while the rust common in this area is a race which comes up from the gulf of Mexico. However, the likelihood of the rust evolving is always a possibility.
For example, another variety, SY Monument from AgriPro Sygenta, has genetic resistance to stripe rust similar to what was found in a previous Sygenta variety, Jagalene.
“If you remember, when Jagalene first came out it had really good strip rust tolerance, but within about four years that fell flat on its face,” Kennedy said. “The rust evolved again and now that particular genetic trait is tolerant of stripe rust again. Those will continue to change all the time.”
Eberle, who helps run the wheat variety trials, spoke about irrigated trials, which were impacted by hail. She analyzed head damage to some of the bushel-per-acre results, which were then adjusted for the yield loss.
“Some of the varieties held up a lot better to the hail than others,” she said. “But picking a variety based on heading date is not going to do you any good to avoid hail.”
Eberle also said she plans to redo the University of Wyoming’s variety trial website to be a more user-friendly website, so that producers can search for varieties and look back at yearly data for yields and search individually for what varieties have higher protein content.
Another consideration for producers that might impact their marketability, according to Kennedy, is a new test called Solvent Retention Capacity (SRC), which he said is gaining popularity with millers to evaluate the quality of the wheat for its baking properties.
“The glory of (SRC) is that it’s done in a test-tube, but it’s almost real time — it takes about five minutes,” he said. “The correlation between SRC and the farinograph and mixograph is about an r of 9.9, where protein is about an r of .5.”
Kennedy said that while protein is better than nothing, it’s not the best proxy for quality. Also added to concerns are discounts elevators place on low protein yields, and the backlog of lab protein tests in some states.
“I think within five years you will start seeing elevators use the SRC test,” he said. “It’s a much more accurate measure of end-user quality. Some of the exporters are actually putting that in their contracts over the mixograph and farinograph.” Producers interested in obtaining the variety results should contact Kennedy at email@example.com, or Eberle at firstname.lastname@example.org.