Two professors and a rising junior at Lynchburg College have teamed up to determine what a local native orchid does to attract pollinators. Their research may have implications for orchids and other flowers that are endangered around the world.
Dr. Nancy Cowden, a biologist, and Dr. Priscilla Gannicott, a chemist, are working with chemistry major Jennifer Thurman '10 to capture fragrances from yellow Lady's Slippers. "The question is, 'Are there certain flowers that do better at attracting pollinators, thus producing more seeds?' It's like the dating game," she said. "Who's wearing the right perfume?"
Yellow lady's slippers don't smell particularly good to humans. In fact, Dr. Gannicott says they have a sort of wet mouse odor. "It's very strong and very unappealing," she said. She and Jennifer can smell the scent, while Dr. Cowden shies away from sticking her nose in one. For her, lady's slippers produce a similar reaction to poison ivy.
Using plastic bags and a small pump, the traditional method in this kind of research, and, separately, a solid phase microextraction (SPME) sampler, a novel method in orchid fragrance work, the trio spent every day between mid-April and mid-May visiting two patches of Lady Slipper's near the Blue Ridge Parkway. They collected about 100 samples of fragrances, using both sampling methods so they can compare results. Using a SPME portable field sampler, volatile fragrance compounds adhere to a tiny fiber on what looks like a large hypodermic needle.
They have also captured some solitary bees that may be the pollinators, but it will likely require an entomologist who specializes in solitary bees to identify them and their mission. The unlucky bees have been frozen for future research.
Back in the lab, Jennifer carefully inserts the "SPME needle" into a Gas Chromatograph - Mass Spectrometer (GC/MS), a $60,000 instrument that separates volatile compounds and identifies them. "I liked doing the outdoor work and being able to bring it inside to analyze," she said.
"It's a real good marriage of biology and chemistry," Dr. Cowden said.
So far, they have detected three major benzenoids in the orchid fragrance. It will take the rest of the summer to go through all 100 samples. Dr. Gannicott said the research would not be possible without funding from Rob Perkin of the Perkin Fund for the GCMS and a research endowment for chemistry students given in honor of the late Dr. Harold Garretson, a former LC chemistry professor.
Dr. Cowden also secured grants for this $12,000 project from the American Orchid Society, the Virginia Foundation for Independent Colleges, an LC Faculty Development Summer Research grant, and the Percy Wootton Research Fund.