This article, by Elizabeth Lane, is part of a series highlighting members of the Office of Sustainability’s Experts Database. In a collaboration with instructor Hannah Monroe’s course, LSC 561: Writing Science for the Public, students interviewed campus sustainability experts and produced short feature stories.
If you’ve ever driven through Wisconsin, you’ve likely seen cows grazing in the fields. Many people don’t stop to think about what happens to the plants they eat or what comes out of the other end. Dr. Rebecca Smith has dedicated her research to that very topic.
Smith’s research focuses on engineering plant traits in forage crops, such as corn, to improve digestion by cows. Improving plant digestibility also increases the quality of manure, allowing for the creation of better quality plant-based biofuels and bioproducts, which increases sustainability and decreases the rate of greenhouse gas emissions. Smith conducts this research to address challenges growers face in growing forage crops in a more sustainable way.
“Sustainability in my research program really comes down to… how are we growing the plants and how are the plants we’re growing impacting the entire ecological system,” Smith said.
Smith was born and raised in Canada, where she obtained her bachelor’s and PhD in Botany. She was inspired to pursue a career in science by seeing other women in science, especially Rachel Carson, a marine biologist whose writings influenced marine conservation.
According to Smith, Carson was uniquely inspiring in that she “saw what was happening to the environment and said this isn’t right, we need to make a change.”
Motivated by that same desire to make a difference, Smith began exploring how plant science could address current environmental issues. With a background in molecular biology, she sought to expand her knowledge by joining a lab focused on plant cell wall chemistry. Her passions and interest in plants and their interactions with a larger system led Smith to do her postdoctoral research in Dr. John Ralphs’ lab. Her research focused on lignin biosynthesis, the creation of lignin in plants.
Building on her postdoctoral research, Smith is now an Assistant Professor in the Department of Plant and Agroecosystem Sciences. Her research tackles the various challenges accompanying dairy sustainability and the development of plant-based biofuels and bioproducts. Smith’s lab uses genetic engineering to improve traits like digestibility in forage crops, making them more efficient sources of plant-based biofuels and reducing the environmental footprint of livestock production.
Cow stomachs contain special microorganisms that break down tough plant fiber, like lignin, through fermentation, a process that creates methane, a greenhouse gas. Altering the lignin’s structure to make it easier to break down makes the digestion process faster and more efficient, reducing gas buildup in the cow’s rumen. The lignin alteration also increases the nutrients in manure, increasing the quality of biofuels and bioenergy made from manure.
Smith says the biggest challenge she faces is the “complexity of the biological system and trying to make our best predictions of what is the best change to make in the cell wall… to get the outcomes we’re looking for.” Another challenge Smith faces is to “alter the lignin in the plant without negatively impacting the plant growth or development” as lignin “forms the basis of [plant] structure…. [transporting] water over long distances through their plant body,” Smith said.
Because plant cells are vastly different from one species to another, it’s difficult to apply the same methods across different crops in a short timeframe. Altering the composition of lignin make up in diverse biological systems is complex and challenging, but can be rewarding when the results benefit the scientific community. This research is important for future generations because it allows us to better understand plant cell wall composition and how we, as a society, can produce more sustainable plant-based biofuels and decrease greenhouse gas emissions.
In the future, Smith hopes to expand her research through the lens of plant-microbe interactions to understand how these lignin alterations affect the larger ecosystem, including microorganisms and plants’ abilities to transport water and capture and store carbon.
Ultimately, Smith’s research shows how innovations in plant science can shape a cleaner, more sustainable future. By working at the molecular level, she’s helping build more sustainable systems one cell at a time.