LSU AgCenter wheat breeder Steve Harrison says this year’s weather provided ample opportunities to evaluate wheat disease resistance in wheat breeding lines and commercial varieties. (Photo by Rick Bogren, LSU AgCenter)

News Release Distributed 06/02/15

BATON ROUGE, La. – 2015 has been a difficult year for the LSU AgCenter wheat and oat breeding program.

“This is my 30th season,” said AgCenter wheat breeder Steve Harrison. “And this is probably the worst set of conditions I’ve seen.”

Growers had a difficult season, too, he said.

Calling it a season “full of challenges,” Harrison said the weather created a good environment to evaluate and select breeding lines as well as commercial varieties, particularly to find those with good resistance to diseases and environmental stresses.

Harrison cited three factors that created particular challenges.

First, he said, spring rains created significant levels of leaf diseases – both bacterial and fungal.

A late freeze caused stem damage, which caused plants to fall over, or lodge. The earliest-maturing varieties were hardest hit, he said.

The major problem for growers was a week of rain during wheat flowering, Harrison said. This led to very high incidences of Fusarium head blight or scab.

“The average grower probably lost 30 percent of yield and crop value to Fusarium,” he said. “Some fields yielded virtually nothing.”

Fusarium head blight is a difficult disease to manage because no variety has complete resistance, Harrison said. Fungicides need to be applied within a window of a week to 10 days from the start of flowering. “But fungicides cannot be applied during rain, so there’s a Catch-22,” he said.

The AgCenter Baton Rouge wheat breeding nursery was particularly hard hit. A late-April storm leveled the nursery plots, and Harrison’s crew had to resort to hand-harvesting to collect enough seed for trials next year.

Other cooperators in the Sungrains consortium of Southern university wheat breeders also had weather problems. But the University of Arkansas and Georgia plots had less bad weather, so the AgCenter program will be able to harvest enough seed from those sites to plant for next year’s yield trials and increases.

Sungrains breeders participate in a cooperative effort by sharing breeding materials and planting experimental lines from the breeding programs at the University of Florida, Texas A&M, the University of Georgia, the University of Arkansas and North Carolina State University in addition to the LSU AgCenter.

“This collaborative research group shares research projects and works together to train graduate students and develop new varieties,” Harrison said.

Sungrains cooperators screen at eight locations across the South and provide evaluations in several environments and serve as backup sources for seed. “It’s an insurance policy for a year like this,” Harrison said.

Despite the demanding growing season, Harrison said two new lines show promise for release this summer.

The breeding line LA 06146 is outstanding, he said. It has very good resistance to rust along with high yield potential.

“It’s a big benefit to our growers because it’s locally adapted and resistant to Fusarium,” Harrison said. “Fusarium resistance is not absolute but can cut losses from 40 percent to 15 percent in a bad year like this.”

A second line is LA 3200. It also has high yield potential, is broadly adapted and has good disease resistance, he said. Unfortunately, it has little Fusarium resistance.

Both varieties were grown in large increase blocks at Georgia Foundation Seed in Plains, Georgia, under the Sungrains agreement.

A new oat variety was co-released this spring with the University of Florida, Harrison said. FL 0720 is a very good forage and silage oat with both high forage production and high grain production. It’s resistant to crown rust.

License is pending and will likely include a Louisiana-based seed company, he said.

A number of Sungrains wheat breeding lines with good scab resistance are in the pipeline but not yet at the release stage, Harrison said.

Harrison works with plant pathologists Don Groth at the Rice Research Station in Crowley, Trey Price at the Macon Ridge Research Station in Winnsboro, Boyd Padgett at the Dean Lee Research Station in Alexandria and Jong Ham in the Department of Plant Pathology and Crop Physiology on campus in Baton Rouge.

“Collaborators are very important in a breeding program,” Harrison said. In addition to the plant pathologists, he depends on two researchers in the School of Plant, Environmental and Soil Sciences – Kun-Jun Han for evaluating forage quality and Niranjan Baisakh for work in developing molecular markers used as part of the breeding program.

Wheat was harvested on 149,838 acres in Louisiana in 2014 with a gross farm value of $63.4 million and value added $11.1 million for a total value of production of $74.6 million.

Rick Bogren