Joe Bouton, Ph.D., senior professor, examines switchgrass plants in a test plot with Brian Motes, senior research associate. Switchgrass, which holds potential as both a bioenergy crop and livestock forage, is a target species of the forage breeding laboratory.
"We've taken the end products of natural selection and imposed additional, more specific selection for traits that we want."
Joe Bouton, Ph.D.,
Research Scientist Hem Bhandari, Ph.D., examines switchgrass plants in the Noble Research Institute greenhouse. The forage breeding laboratory is working to develop hardier varieties of the native prairie grass as a forage for livestock as well as a potential bioenergy crop.
- Forage Breeding Laboratory Staff
- Joe Bouton, Ph.D., principal investigator
- Hem Bhandari, Ph.D., research scientist
- Brian Motes, senior research associate
- Dusty Pittman, research associate
- Wes Scruggs, research associate
- Kelly Harris, research assistant
- Willy Inselman, research assistant
- Lynne Jacobs, research assistant
- Curtis Larson, research assistant
- David Kirkpatrick, research technician
- Cameron Williams, research technician
When it comes to making better forage for food and fuel, Joe Bouton, Ph.D., has a lot of tools at his disposal. And he uses every one of them.
Bouton, who served as Forage Improvement Division director from 2004 until summer 2010, has returned full time to the laboratory and leads the forage breeding lab, one of seven research units within the division devoted to developing new cultivars for grasses, legumes and small grains for grazing and hay production.
At its core, the forage breeding lab translates basic plant science research into tangible plant varieties for use by farmers and ranchers in Oklahoma and Texas, as well as similar climatic regions around the world.
"What we do is build on Darwinian outcomes. We've taken the end products of natural selection and imposed additional, more specific selection for traits that we want," said Bouton, a plant breeder, geneticist and agronomist. "We're doing the same thing nature does, but we're going in a more specific direction to develop a group of true breeding plants more suited to a highly managed ecosystem like a farm or ranch."
Wheat is a good example of how this works. In nature's unmanaged ecosystem, primitive wheat seed was light and chaffy, a far cry from today's plump kernels. It perpetuated itself by scattering its seed directly on the ground or clinging to animal fur to be deposited later. It also matured its seed at different times. "So wheat was selected and bred away from that natural ability," Bouton explained. "Now it has much larger kernels that all mature at a specific time, and therefore it became a crucial food crop."
The process of effecting change is completed through plant breeding, where the team uses the diversity of all the plants and tries to manipulate genes to select for specific and value-added traits. "We could just look at plants and select those that have the traits we want like specific flower color. But our approach is to narrow down the broad populations to specific ones that have all the main traits agricultural producers need and want," Bouton said. "By knowing something about the genes that underlie these traits, it is easier for us to make progress."
Bouton uses two analogies to explain the trait selection process. "Think of a funnel. At the broad end is all the germplasm of that species. What makes it through the narrow end and out the funnel are plants with the desired trait," he said. "It's also a lot like the way some baseball players make it to the major leagues. Millions of kids play the game at any given time, but gradually that population is selected way down so that only the very best play professionally."
The methodologies used by Bouton's 10-member team range from conventional breeding techniques to biotechnology-based tools. When they are assessing plants for a unique trait, the team often looks to another Forage Improvement Division research unit, the molecular markers lab, to identify genetic markers to speed up the breeding process.
"Our approach is collaborative and fluid, so we also draw from the research of other units. We all have the same goal of producing plants that have certain traits. We just do different things to achieve this," Bouton said. "Biotechnologies are tools that can make everything more efficient."
Noble Research Institute Associate Professor Malay Saha, Ph.D., who oversees the molecular markers lab, noted that in conventional breeding, plants are selected by how they appear, but molecular markers enable selection based on the genes responsible for expressing specific traits. "This method results in greater confidence in trait selection," he said. "And because the marker identification process requires only DNA from the plant, it also saves a lot of time. A conventional breeding trial can take from a year to a year and a half, whereas a molecular marker method takes as little as two to three months."
One of the markers identified by Saha's group is for digestibility in tall fescue, which is grown primarily for cattle grazing. "The ultimate goal is for the animals to gain the most weight in the shortest period of time. If the forage isn't palatable and digestible, that won't happen," he explained. "By identifying the digestibility marker, we can help develop a more easily digestible fescue."
Once a specific trait like digestibility has been identified and introduced into plant material, Bouton's team employs a series of steps, some in collaboration with the Noble Research Institute Agricultural Division, to determine whether the experimental material can successfully transition into an improved cultivar. Many of those functions are coordinated by Senior Research Associate Brian Motes, whom Bouton depends on to run the laboratory's day-to-day operations."We take teamwork seriously," Bouton said. "Brian is the straw that stirs the drink."
That "drink" has many ingredients and covers significant territory, extending well beyond the Ardmore laboratory. Motes regularly travels to research stations from Haskell in northeastern Oklahoma to Overton, Texas, about 30 miles east of Tyler, to ensure the proper handling of trials for both conventional and regulated transgenetic plants (those genetically engineered to include a trait transferred from a different species of plant). The trial material is sent even further away to several universities, including the University of Georgia, Texas A&M University and Mississippi State University, which generate additional research data.
"We like testing our material in different geographic locations, so the university collaborations are vital," said Motes.
Motes also coordinates the unit's plant variety protection trials (PVP) for cultivars close to commercial release. PVPs are particularly labor-intensive and lengthy. The data collected from PVP trials are part of a packet submitted to the USDA's Plant Variety Protection Office for a Certificate of Protection. This certificate grants legal intellectual property rights to the breeder. "We collect data over several years, focusing on the cultivars' phenotypic (physical) traits. We then compare these traits to the traits of several common varieties that have been around for years," Motes said. "This information allows us to distinguish our cultivar from other commercially available varieties."
A major focus of the forage breeding lab's work is domestication of switchgrass for both forage and bioenergy applications. Their efforts already have resulted in three varieties that have been adapted for use in the Southern Great Plains, upper Great Plains and Gulf Coast.
"As a bioenergy crop, switchgrass would be grown as a feedstock for conversion to fuel and for biopower, where it could be compressed and burned with coal to reduce emissions. The third avenue for domesticated switchgrass would be direct feeding to cattle," Bouton said. "The beauty of switchgrass is that it can go any of those routes. That's a decision that will be made by the farmer. All we can do is try to make our varieties as flexible as possible as quickly and thoroughly as possible."
At the same time, Saha's team is applying molecular breeding techniques by combining two methods: developing new populations of cultivars through cross-breeding evolution and molecular markers that identify desired traits.
Among the many reasons switchgrass is an appealing option for both forage and bioenergy are that it is a perennial, grows quickly and can be grown with minimum inputs of nutrients and water.
"If you plant switchgrass one time, it can give you a good yield for 10 to 20 years," Saha said. "When senescence starts with the first frost, the plant mobilizes nutrients from the shoot to the root, where they are stored as start-up food for the next growing cycle in spring. It's a smart plant."
Saha's group hopes to produce switchgrass plants that are ready to be made into biofuel. "The greater the plant yield, the more energy and forage that can be produced," he added.
Additionally, Bouton's team assists Principal Investigator Maria Monteros' laboratory, that, like Saha, uses advanced technologies to breed new forage crops. Monteros, however, is focused on forage legumes, such as alfalfa and white clover.
The forage breeding lab helps integrate discoveries from Monteros' program into tangible products by providing germplasm platforms that have been specifically selected and improved for grazing tolerance.
"We could not accomplish our goals without their invaluable support and expertise," Monteros said. "I'm confident that the process we've developed for alfalfa and white clover can be applied to other species that are relevant to the Southern Great Plains."
With the increase in world population and the decrease in usable land, plant breeding will play a paramount role in the success of the agriculture industry's ability to feed the planet. "Using all the tools we have to create managed ecosystems is the only way we can produce enough food and energy for future generations," Bouton said. "We must continue to seek ways to improve plants through all possible avenues and explore new possibilities so that we can meet the ever-growing demands on agriculture."