Trials reveal best organic wheat varieties

It takes years for a wheat variety to make it from testing to availability for planting. For organic wheat, the process is tougher because of additional criteria, says Richard Little, University of Nebraska organic wheat breeding specialist and coordinator.

Little led tours this summer of four UNL organic research plots, including those located at Haskell Ag Lab near Concord. As part of the tours, growers and researchers observed varieties growing in plots, with some that would exhibit desirable traits like high yield and bread-making quality.

“Organic farmers are sensitive to the market, which varies from any protein content for breakfast cereals or feed to moderate to high protein content for the bread market,” Little says. “The UNL wheat breeding program builds disease resistance to leaf rust and stem rust into all new releases.”

When selecting wheat varieties to plant, Stephen Baenziger, UNL small grains breeder, says farmers should consider “disease and insect resistance, weed suppression, end-use quality, standability and adaptation to organic systems.”

Researchers are concerned about these qualities, too, as they decide which lines to increase for production. But the process takes “12 to 14 years from the cross and three years from the decision to increase,” Baenziger says. So wheat breeders have to make an educated guess as to the qualities producers will need nearly 20 years down the road.

“Organic farmers need a cool-season crop like wheat in their rotation to break the cycle of warm-season weed seed production,” Little says. Because of wetter conditions in the east, he says farmers should consider varieties with resistance to preharvest sprouting and fusarium head blight, because both problems can cause rejected shipments of grain. Competitiveness with weeds is another trait of interest.

To test bread quality, Little says, “We have a wheat quality lab where our samples are milled and baked using a standard lab protocol for white flour pup loaves. In addition to evaluating mixing tolerance and water absorption, which is important to the industrial bread maker, we evaluate loaf volume and bread cell structure.

“Karl 92 continues to reign supreme among released varieties for bread quality,” Little says. But it has much lower yields in western or eastern parts of the state compared to other varieties. Wesley matches Karl 92 for bread quality, but has serious susceptibility issues to fusarium head blight.

Experimental lines

Two experimental lines tested over the past two years are expected to match or exceed Karl 92 and Wesley for bread quality, Little says. NE07444 is adapted for planting in the east, and NW7505, a hard white line, is adapted to the west. More testing is required before these lines might be released. NE05425 has strong gluten, with potential for high-quality 100% whole wheat bread. NW03681 is a hard white line that has good milling and bread making quality, with high yields in western Nebraska.

Having certified organic cropland at UNL testing stations has been a key aspect of the wheat trials. “It is important for the researchers and technicians to know first-hand what farmers must do to maintain their organic certification,” Little says. “The commitment to infrastructure, equipment and personnel that goes along with operating an organic research farm enables researchers to make long-term plans.”

“Organic farmers need research programs that focus on breeding new cultivars specifically for organic systems with an emphasis on disease and pest resistance, response to green manures and end-use quality,” says Elizabeth Sarno, UNL Extension educator and organic project coordinator. “I feel as our nation looks toward developing more resilient sustainable cropping systems, research on long-term organic systems will have beneficial results for all farmers.”

For a summary of 2011 recommended wheat varieties for organic production, go online to agronomy.unl.edu/breedingorgsys or email Little at rlittle2@
unl.edu
.

Breeding wheat is long process

It takes 12 to 14 years for select wheat varieties to be selected, increased and released. Wheat is self-pollinated, so that each successive generation will be more genetically uniform than the preceding generation. From the 800 crosses made each year, breeders get 40,000 head rows, with each being a potential variety.

That’s narrowed down to 800 lines in the next generation, and by the F10 generation, it is down to 30 entries. With each subsequent generation, the seed planted back is more genetically pure within each plant. Some plants are “off types,” and they are weeded out to improve purity of the line.

“Testing in organic environments begins at UNL at F6,” says Richard Little, University of Nebraska organic wheat breeding specialist, “after the breeding program has weeded out potential varieties that are too early or late in heading, have poor bread quality, lack stem rust resistance or are susceptible to winterkill.”

At F11 generation, 1,000 heads that are uniform in appearance are selected and sent to Arizona to increase. They are then grown as the increased “breeder” seed at Mead and set for release as Foundation seed to certified seed growers in the following year.


10111447a.tif

IN THE FIELD: At a wheat tour at Haskell Ag Lab earlier this summer, Richard Little, University of Nebraska organic wheat breeding specialist, described the process plant breeders use when selecting varieties in trials.

This article published in the October, 2011 edition of NEBRASKA FARMER.

All rights reserved. Copyright Farm Progress Cos. 2011.