Zoning in on the genetics of the world’s largest flower

Photo of Dr. Todd BarkmanDr. Todd Barkman, a WMU professor of biological sciences, grew up in Pinckney, Mich., a rural area that inspired his interest in plants.  While majoring in botany as an undergraduate at Michigan State University, he had the opportunity to grow orchids for the botany department. "I fell in love with orchids," Barkman said.  "I decided I wanted to work with and study orchids for the rest of my life."

Barkman has been teaching at WMU for nine years. He grew up in Pinckney, Mich. and admits growing up in a rural area is what first inspired his interest in plants. Barkman attended Michigan State University as an undergraduate majoring in botany. At MSU, he had the opportunity to grow orchids for the botany department. "I fell in love with orchids," Barkman said. "I decided I wanted to work with and study orchids for the rest of my life." 

The desire to continue research in botany became even more important to Barkman after he took a class about global ecology as an undergraduate. "The class was about how acid rains, global warming, desertification, and tropical deforestation are depleting great natural areas," said Barkman. "I realized I needed to do something to help alleviate this problem we are dealing with."

Orchids were the main focus of Barkman’s research while working on his master’s degree at MSU and into his doctorate program at the University of Texas in Austin, when he conducted research in northern Borneo, where orchids grow in the wild. While in Borneo, he learned about the Rafflesia plant, which is a native of the area. 

Photo of Dr. Trond Schumacher

Dr. Trond Schumacher, University of Oslo, Norway, collaborates with Barkman to study this incredible plant.

"We realized we know virtually nothing about Rafflesia," Barkman said. "It was too fascinating to ignore, so my international collaborators and I decided to use modern DNA technology to learn more about the biology of these plants."

Barkman has spent a lot of time abroad in the pursuit of advancing understanding of Rafflesia. He collected DNA samples of about 15 species of the plant in Malaysia, Indonesia and the Philippines. 

"Two plants had remarkably similar DNA; one small, one large, so they could be related," Barkman said. "We used the DNA samples to determine how long it took for these changes to occur. Some species appeared around one or two million years ago. Some reached a large size in a very small amount of time. We suspect the growth rate isn’t slowing down, so who knows how big they will become."

Barkman continues to research what causes Raffelesia to give off an offensive odor that is similar to rotting flesh. He said some people believe that Rafflesia's odor may attract flies for pollination. "The smell isn't a painful smell like a skunk," Barkman said. "It's more like a week-old dead possum. It’s not that strong from a short distance, but when you put your face down in it, it smells really bad. However, it doesn't make you want to throw up and it doesn't dissuade people from going to see it." Rafflesia is endangered in part because local people, who need to plant gardens to survive, chop down forests for their gardens, which causes habitat loss. "The worst scenario is tropical logging," Barkman said. "Loggers clear huge areas of forest whereas local people only clear small portions. Plantation planting is also a problem for Rafflesia. Half a state can be cut down in order to grow things like coffee."

Photo of RafflesiaNot only does Rafflesia face habitat loss, but the plant is challenged by it complex growing habits. "Unlike other plants, Rafflesia is parasitic," Barkman said. "Rafflesia needs a habitat patch, a host plant, and to be able to land on the host in order to grow and develop inside of it. The good news is that locals have realized the tourist attraction these plants have become. Locals have started making a good living out of farming Rafflesia and bringing in tourists."

The biweekly "Current Biology" published Barkman's research, "Accelerated Rates of Floral Evolution at the Upper-Size Limit for Flowers," in its October 14 issue. Barkman authored the report with Seok-Hong Lim, a 2006 Western graduate; Domingo Madulid, Philippine National Museum botany division, whom Barkman met during his travels; Kamarudin Mat Salleh, University Kebangsaan Malaysia, School of Environmental and Natural Resources; Jamili Nais, Sabah Parks, Malaysia, both Malaysian collaborators with Barkman; and Mika Bendiksby and Trond Schumacher of the University of Oslo, Norway. 

Though Barkman has a special interest in Rafflesia, he admits all plants are fair game to study. "I also study plant evolution, specifically how plant enzymes evolve new functions over time," Barkman said. "Enzymes do various things in our bodies and in plant bodies as well. In plants enzymes produce a rich array of chemicals. Many of these chemicals we enjoy because they produce flavors and scents that we are familiar with. Oil of wintergreen used in chewing gum is from plants, which is another thing I study. I look at how plants produce that chemical and how that process has evolved over time."

The research environment that WMU fosters was important in Barkman’s decision to teach here; he said WMU’s large international student population was another plus. "The twinning program WMU has with Sunway College in Malaysia was one feature that attracted me to this university," Barkman said. "As a result of that program, we have hosted hundreds of Malaysian students on campus at any given time. My wife is from Malaysia and because much of my research is in Malaysia, it’s nice to be in a community with people who can relate."

Barkman teaches several classes at WMU, including, general botany, systematic botany, plant physiology and introductory biology. When not teaching or researching, he enjoys spending time outdoors with his wife and three children. 

Portions of this story appeared in a Western Herald story by Josh Holderbaum on November 13, 2008.

Story by Julia Valentine