Professor wins grant for faculty-student tree research

Botany professor Rachel Spicer poses with plants inside Connecticut College's newly renovated greenhouse.
Botany professor Rachel Spicer poses with plants inside Connecticut College's newly renovated greenhouse.

The National Science Foundation has awarded Rachel Spicer, assistant professor of botany, a three-year, $395,064 grant for research that addresses fundamental questions about how trees grow. The work has practical applications for biofuel development and forest generation.

The project will provide advanced summer research opportunities for nine Connecticut College undergraduates and for an additional five to 10 students during the academic year. The grant, which begins in the fall of 2013, also includes funds for equipment and for travel to research conferences by Spicer and students.

Spicer is researching how the fast-growing poplar tree (Populus tremula x alba) lays down the intricate system of microscopic pipes that move water and sugar through the wood to the leaves and roots. The hormone auxin guides the process. But scientists don’t know what determines where the pipes are located.

 “Very little is known about how woody stems develop, and how connections are formed between the older portions of a stem and the young leaves,” Spicer said. Her research will shed light on how the vasculature – the piping network – is established.

The pipe structure determines how permeable the wood is. And the permeability affects a number of characteristics that are important for determining the best uses for a given wood. It’s a key property, for example, for wood used as biofuel. The piping system is also important for tree growth because it affects how fast a tree can get water to its leaves, which could influence the rate of growth.

Students will do advanced work on gene expression – measuring where and how much a gene is turned on or off – and will use mass spectroscopy to quantify auxin from different parts of a tree. They will help Spicer track the movement of auxin from the young leaves to the woody stem below, in order to trace the connections between new growth in the spring and the woody tissue from previous years.

Few undergraduates have the opportunity to do that level of research, Spicer said. “The chemistry involved is quite challenging,” she said. Two students are already helping with independent research and doing excellent work. Both are doing senior theses on the project – one on gene expression and the other on chemistry. Spicer hopes the project encourages more students to pursue careers in plant biology.

Spicer, whose grandfather was a tree biologist, has always loved trees. She decided to become a forestry major after seeing tree vasculature under a microscope as a freshman at the University of Massachusetts. “It was the most beautiful stuff I’d ever seen,” she said. Spicer went on to earn a master’s degree from Oregon State University and a Ph.D. from Harvard. She joined Connecticut College in 2010. This is her first project as a principal investigator on a federally funded award as a professor.

The grant runs for three years and is 100 percent federally funded.

About the National Science Foundation

The National Science Foundation is an independent federal agency. With an annual budget of $6.9 billion, the NSF is the funding source for approximately 20 percent of all federally supported basic research conducted by U.S. colleges and universities.

March 4, 2013