Professor Gary Tallman
Fighting the Effects of Global Warming, One Cell at a Time
Biology Professor Gary Tallman has been toiling away in labs for almost 20 years to understand how plants adapt and survive under consistently warm temperatures — a question that could be crucial to the future availability of food. But it's taken the famous face of a recent vice president to finally bring widespread public attention to the work of Tallman and other scientists like him.
Thanks to Al Gore's book and documentary "An Inconvenient Truth," more and more people are concerned about the effects of global climate change. It's been a long-standing issue for Tallman, who worries about what warming temperatures could do to farmers' crop yields.
"The population is expected to double by 2050, and we are going to need more food production to support our world," he says. "We may have to start breeding plants to withstand increased carbon dioxide levels and higher temperatures. Right now, we're trying to slow emissions, which I think is the best option. But if that doesn't work, we need a plan B."
Tallman, who holds the Taul Watanabe Endowed Chair and is director of the Office for Faculty Research and Resources, studies thermotolerance — the way plants adapt to survive in high temperatures. He became interested in the topic while doing his post-doctoral work, when he heard a plant biologist speak at a seminar about how he had cloned a potato from a single cell. "I could see the future of that idea would allow you to manipulate the cells before regenerating them, so you could create characteristics such as disease resistance," Tallman says.
So he started studying plant cells, or specifically one type: the guard cell. It's a kidney-shaped cell on leaves that enables plants to take in carbon dioxide and keeps them from losing too much water. It can be easily isolated from leaves so scientists can grow it in test tubes. Tallman has focused on the guard cell of Nicotiana glauca, a weedy tree tobacco native to Argentina that has an easy-to-peel skin, allowing him to quickly remove cells for study.
Over time, Tallman discovered these guard cells can withstand temperatures of up to 100 degrees Fahrenheit and still survive. At lower temperatures, they need two hormones — auxin and cytokinin — to continue growing and dividing. Once the cells heat up, they no longer require the hormones to survive — but they also stop dividing.
"As the cells become thermotolerant, they also become thermoinhibited, meaning they're not growing," Tallman says. "Now we're trying to figure out which steps in the process are preventing them from dividing."
If he can isolate the answer, then he can move to the next step: providing the cells with new characteristics so they can continue growing even as the air around them heats up.
Tallman has engaged numerous students in his research, many of whom have added their own discoveries. He regularly mentors students through the Science Collaborative Research Program, which allows Willamette undergraduates to research alongside professors.
He has written more than 30 peer-reviewed scientific articles and book chapters on plant physiology and cell biology, and his work has garnered him multiple national research grants — including $252,000 from the National Science Foundation and a $39,000 grant from the M.J. Murdock Charitable Trust.
Tallman hopes his continued work and discoveries will engage future biologists in crucial research to address climate change. Gore is helping a bit with that, too. "More students are becoming interested in this type of research because they see its relevance," Tallman says.
Willamette's Department of Biology celebrates its 100th anniversary in September. You are invited to the festivities. For information, go to Centennial Celebration Web site.