HIGH POINT, N.C., Sept. 25, 2014 – High Point University faculty and student researchers are one step closer to resolving a botanical mystery. Their research on why some shade-loving plants have red or purple pigments on the underside of their leaves was highlighted recently in Planta, a prominent botany journal.
Nicole Hughes, assistant professor of biology, along with HPU alumni Kaylyn Carpenter ’11, Scotty Keidel ’13 and Charlene Miller ’13, sought to find out if the pigment on the underside of leaves offers a specific benefit to plants like African violets and begonias.
“We know from previous studies that the red or purple pigment in plants, called anthocyanin, acts like a sunscreen in leaves, protecting them from high light stress,” says Hughes. “The idea that we proposed was that the red coloration acts as a sunscreen, but by being on the lower surface rather than the upper surface, the sunscreen does not interfere with light capture during the shady times of the day.”
They conducted their experiment over the course of a couple summers using Colocasia esculenta (‘mojito’) – what a backyard gardener may recognize as an elephant ear. In their research, they looked at the pigment patches on the upper and lower surfaces of the leaves to compare the photosynthesis and light stress between the tissues. Their results showed that the sunscreen effect was present on the undersides of the leaves, but there was no evidence of the pigments on the top interfering with photosynthesis.
The mixed results mean HPU students will continue their work while studying the Colocasia esculenta (‘mojito’) planted specifically for this research in the Welcome Garden on HPU’s campus. HPU biology majors Harris Coley and Sean Ireland will take advantage of the educational benefits provided by the Mariana H. Qubein Arboretum and Botanical Gardens while testing an alternative hypothesis using the same plant.
“This research sheds light on a nearly completely unstudied phenomenon in plants,” Hughes says. “It is really fun and exciting to be able to ask questions that nobody has ever asked before about the natural world. Curiosity about the natural world is at the heart of the study of biology.”