A national consortium of wheat breeders and scientists, led by Jorge Dubcovsky at UC Davis, was awarded a $5 million grant Feb. 16 by the U.S. Department of Agriculture to implement modern technologies that will equip breeders to produce higher quality, disease-resistant wheat, one of the world's oldest and most widely used food crops.

The technology, known as marker-assisted selection, allows the researchers to use the genetic information found in the plant's DNA to select those plants that carry desirable traits, such as disease resistance and improved quality.

"This grant will enable us to expand our research effort, provide training for graduate and undergraduate students, and share practical information about the technology with growers across the country," said Dubcovsky, project leader for the Marker Assisted Selection program for wheat. The program includes breeders and researchers at universities in 17 states and at four U.S. Department of Agriculture laboratories.

Developing new varieties

Wheat is unique among the major crop plants, Dubcovsky noted, in that researchers from public universities and government laboratories, rather than private companies, are largely responsible for providing new varieties to U.S. wheat farmers. For example, from 2001 to 2003, public wheat varieties accounted for 78 percent of U.S. wheat production, which amounted to an annual average of 38 million metric tons valued at more than $5 billion.

"The main objective of the Marker Assisted Selection project is to incorporate modern selection technologies to increase the competitiveness of these public wheat breeding programs," Dubcovsky said.

Molecular markers are landmarks in the chromosome maps of plants or animals, which can be used to monitor the transfer of specific chromosome segments known to carry useful traits. Breeders use these markers to more precisely select for the best combinations of traits.

In addition to using existing markers, the project also will "map" new markers associated with important agronomic traits. This is done by identifying the relative positions of marker genes on a chromosome and then measuring the association between the markers and the targeted traits. Researchers involved with the project will map, validate and implement these molecular markers for quantitative traits prioritized by the wheat industry.

U.S. wheat researchers already have developed protocols for more than 50 molecular markers for genes that confer disease resistance and certain quality traits. They have used these markers in a previous project, also led by UC Davis, to incorporate valuable genes into the best breeding lines for 10 different market classes of wheat.

"These wheat lines will be used in the new project to deploy the targeted genes into thousands of lines across the breeding programs, with the help of high-throughput genotyping laboratories established by the USDA," Dubcovsky said. "Those laboratories will use modern equipment to provide breeders with the thousands of molecular markers required for this approach."

More information about the Marker Assisted Selection program is available online at http://maswheat.ucdavis.edu/.

The project is funded through USDA's Cooperative State Research, Education and Extension Service and administered through its National Research Initiative. The initiative supports research, education and extension grants that address key problems of national, regional and multistate importance in sustaining all components of agriculture.