By Chris Hubbuch
In the King Hall greenhouse on the UW–Madison campus, Rebecca Smith stands amid a potted jungle of sorghum, clipping stalk segments into a plastic bin to be weighed and cataloged. Seeds, bagged and labeled, are stacked to the side. Tissue samples have been flash-frozen in liquid nitrogen for chemical and genetic analysis.
The plants have an extra piece of DNA that increases their production of a chemical that weakens bonds in the cell walls. The walls are like bank vaults full of carbohydrates; the goal is to make it a little easier to break in and turn those sugars into energy.
With more than 50 plants, it’s tedious but necessary work to figure out which specimens perform best depending on where the extra gene landed and how active it is. “Best” in this case means the plant cell walls are easiest to break down after harvest, but the plants otherwise grow like native sorghum, a hardy crop that withstands arid conditions and produces a lot of organic material, Smith says.
An assistant professor in the Department of Plant and Agroecosystem Sciences at CALS, Smith investigates how forage and bioenergy crops develop at the cellular level. She uses her unique combination of skills to engineer new varieties to help solve some of humanity’s biggest challenges.
As a scientist with the Great Lakes Bioenergy Research Center (GLBRC), Smith spent the past decade researching ways to grow non-food plants as feedstocks for fuels and chemicals traditionally derived from petroleum. Now, as a new member of the Dairy Innovation Hub, she is working to grow crops that are easier for cows to eat. Both projects aim to make farming more sustainable, bolster rural economies, and ultimately reduce greenhouse gas emissions.
“The goal is to improve digestibility,” Smith says. “There are synergies in what makes a good plant for biofuel and for feed.”
Source : wisc.edu