Karol Osborne | 4/23/2018 4:53:05 PM
(04/23/2018) WINNSBORO, La. — LSU AgCenter experts, speaking at the annual wheat and oat field day held April 18 at the LSU AgCenter Tom H. Scott Research, Extension and Education Center in Winnsboro, reported impressive wheat production this year, which could offset depressed prices.
AgCenter plant pathologist Boyd Padgett said disease issues are the lightest he has seen in more than 30 years working with wheat.
Wheat acreage in Louisiana continues to decline. Growers planted 15,000 acres this year, which is lower than last year’s then-record low of 20,000 acres. Padgett said this is primarily because of scab disease, low market prices and several years of inclement weather.
AgCenter plant pathologist Trey Price said Fusarium head blight, or scab disease, has devastated the wheat industry over the past three years, resulting in yield losses from 15 to 20 percent.
To optimize disease control, Price said timing fungicide applications during flowering is critical. “You have only about a five-day window, and even with the best fungicide, only 50 percent control can be expected,” he said.
“I’m confident wheat will rebound over time,” Padgett said, adding that genetic resistance will be a key factor for combating scab disease.
AgCenter wheat and oat breeder Steve Harrison said there are no silver bullets at this time, but about a dozen genes can provide some level of resistance.
“We’re getting there in terms of resistance,” Harrison said, noting there will likely never be complete resistance, but moderate resistance will be available.
AgCenter researchers showcased more than 50 wheat varieties and 33 oat varieties at the field day, including late- and early-maturing varieties.
Harrison said the condition of the station’s wheat and oat nursery is the best he has seen, predicting as much as 100-bushel yields from some entries in the wheat variety trials.
Oats have had a near-perfect growing season, and like wheat, oats at the station exhibit a very high yield potential, very little lodging and no crown rust disease, he said.
Oat varieties produced in Louisiana are grown for deer food plots, winter pasture, cover crops and grain for horses and other livestock and are not used for human consumption.
Researchers are working to develop the nutritional and milling characteristics needed to attract oat processing facilities to the South and provide a value-added market, Harrison said.
Harrison said oat acreage could increase if producers planted oats instead of wheat as a winter cover crop.
“Oats have the advantage of providing more and earlier biomass and do not serve as hosts of Hessian fly and most wheat diseases,” he said.
To manage Hessian fly, one of most destructive pests in wheat production, AgCenter entomologist Sebe Brown recommends an integrated approach using tillage, crop rotation, planting date, variety selection and insecticide application strategies.
“Burning wheat to control Hessian fly infestation is not enough; the stubble must be buried,” he said.
Brown made the following recommendations:
— Try to plant a resistant wheat variety.
— Avoid planting a susceptible variety into an infested field.
— Follow LSU AgCenter recommended optimal agronomical planting dates for best yields.
— Use current variety trial charts for variety selection.
— Select seed treatments based on what is most appropriate according to variety selection.
“If planting a resistant variety to Hessian fly, you will still need a seed treatment to control aphids in the fall,” Brown said.
Transmission of barley yellow dwarf virus is the main concern with aphid populations, which must be controlled in the fall to reduce the virus spread in the spring, Brown said.
Aphid infestation is worsened by dense stands and high rates of nitrogen fertilization, he said, and can be controlled by avoiding overfertilization.
Most insects in wheat, including stink bugs, aphids, Hessian fly and army worms, are easy to control with a lower label rate application of a pyrethroid, he added.
AgCenter agronomist and weed scientist Josh Copes said wheat yield reductions from weed competition occurs early in the growing season and recommends herbicide application be made in the fall.
Italian ryegrass is one of the most yield-limiting weeds infesting wheat, Copes said, adding that herbicide options in wheat are numerous and should be selected based on weed spectrum.
For wheat and other cereals grown as winter cover crops, growth stage is an important factor in glyphosate burndown performance, Copes said. Hard water and temperature fluctuations can also hamper glyphosate’s ability to perform optimally.
AgCenter research found the best and most consistent control of wheat was observed when glyphosate was applied after jointing and before boot stage or after wheat heading, he said.
Copes said adding ammonium sulfate will mitigate effects of hard water and recommends watching daily air temperatures to ensure highs are above 55 degrees and lows are above 40 degrees at least three days before and after making any applications.
AgCenter associate vice president Rogers Leonard provided updates on reorganization efforts and announced the upcoming crop production and pest management field day set for June 19 at the Scott Center in Winnsboro.
Leonard said AgCenter research stations exist to serve stakeholders.
“This is your station, not ours,” he said. “You allow us the opportunity to manage it for you.”
LSU AgCenter plant pathologist Trey Price provides treatment recommendations based on wheat fungicide trials at the AgCenter wheat and oat field day held April 18 in Winnsboro. Photo by Karol Osborne/LSU AgCenter
LSU AgCenter wheat and oat breeder Steve Harrison shares results from oat variety trials at the wheat and oat field day held at the AgCenter Tom H. Scott Research, Extension and Education Center. Harrison said the oat and wheat nurseries at the station were the best he has seen. Photo by Karol Osborne/LSU AgCenter