ARS, Cornell University Team Up to Improve Forage Crops

High-Tech Program Provides Modern Insights into Plant Breeding

Modern agriculture is a lot more than just digging in the dirt; today a breeder's toolbox might include genomics and informatics (data management and software) along with their shovel and spade.

Deborah Samac, research geneticist and research leader with the ARS Plant Science Research Unit in St. Paul, MN, is working with a group of scientists at ARS and Cornell University to develop new tools that improve the processes used in plant breeding. The group, which is known as Breeding Insight specializes in developing inexpensive DNA markers that make it easy for plant breeders to identify regions in chromosomes that are associated with important traits. Breeding Insight is also developing integrated methods for recording plant traits in the field and managing data and providing software tools that help breeders rapidly increase the rate of genetic gain in their breeding processes.

"ARS forage breeders are tasked with breeding solutions for 'grasslands' – rangeland, pasture, bio-energy, and harvested forage systems," said Heathcliffe Riday, research geneticist with the ARS U.S. Dairy Forage Research Center in Madison, WI. "The resources and support that Breeding Insight provides allow traditional breeding programs to engage in more intensive and advanced breeding methodology, which might otherwise not be available due to resource limitations."

Alfalfa, which is the subject of one of the five Breeding Insight pilot projects (along with blueberry, sweet potato, table grape, and trout/salmon), is a perennial crop of tremendous agricultural importance. According to Samac, the legume has very high levels of DNA diversity, so developing DNA markers that are "universal" to nearly all alfalfa cultivars will make it easier to find desirable traits.

The third most widely grown crop in the United States, alfalfa produces more protein per acre than any other crop and serves as the foundation of feed for dairy and beef cattle, horses, and other livestock. It is also a key export.

Researchers grow alfalfa at a breeding nursery. (Photo courtesy of Heathcliffe Riday, ARS)

"We will use the Breeding Insight markers to speed up the breeding of alfalfa plants with improved fiber digestibility for ruminant animals, so they get more energy out of every mouthful," said Samac. Ruminants are animals, like cows, that employ fermentation in their digestive systems.

According to Samac, Breeding Insight research can also improve farmers' economic bottom line.

"Alfalfa breeders have been 'stuck' for decades without much change in forage yields," she said. "This is due, in part, to the complex genetics of alfalfa. U.S. farmers want to get more bales from every acre of ground, so increasing yields is very important. Having markers and computer programs to associate DNA with yield data will give breeders the tools they need to do that."

In addition to finding DNA markers that improve alfalfa's nutrition and yield, Breeding Insight also tries to develop a healthier plant. For instance, one of Samac's roles in the project is to locate DNA markers that identify genes that help plants resist a disease called Aphanomyces root rot, which plagues alfalfa growers throughout the Midwest. Primarily associated with wet or poorly drained soils, the disease can cause crop loss of up to 70%. By using advanced techniques like genomics, Breeding Insight is helping growers fight age-old problems like root rot with new, more effective solutions. – By Scott Elliott, ARS Office of Communications

Note: Animal and aquaculture breeders, growers, and processors can also benefit from Breeding Insight processes.