Different Strokes: USU Ecologists Say Plants Produce 'Astonishing' Array of Metabolic Substances

Plants of many species harbor a vast number of specialized metabolites — chemical substances that play a variety of roles in sustaining a plant and its offspring. Primary metabolites are essential for the plant’s basic survival and growth. The function of secondary metabolites is less understood, but they appear to play a critical role in a plant’s interactions with its surrounding environment.

“Secondary metabolites were once thought to be byproducts, with no function,” says Utah State University ecologist Noelle Beckman. “But we’re learning these compounds actually provide important and varied functions that influence ecological and evolutionary interactions across many levels of biological organization — from individual plants to ecosystems.”

Beckman, associate professor in USU’s Department of Biology and the USU Ecology Center, along with Gerald “Jerry” Schneider, USU postdoctoral researcher, reported findings about secondary metabolites, stemming from research the scientists conducted with plants from Panama’s Barro Colorado Island, site of the Smithsonian Tropical Research Institute, in the March 22 online issue of Plant Biology. The research was supported by the National Science Foundation.

Beckman says plants, though rooted in the ground, are hardly excluded wallflowers — especially if they bear tasty fruit.

“Plants are subjected to many plant-biotic interactions,” she says. “Creatures great and small interact with plants, ranging from large, ravenous herbivores to also-hungry insects to microscopic pathogens.”

These interactions can be antagonistic or mutualistic, with secondary metabolites heightening a plant’s defense against harm or facilitating beneficial interactions that promote survival and reproduction, including seed dispersal by animals.

Beckman and Schneider’s study compared patterns of metabolic variation and distribution in closely related species of Psychotria (wild coffee) and Palicourea (hot lips or girlfriend’s kiss) shrubs with bird-dispersed fruit.

“We’re just scratching the surface on understanding these compounds, which we hypothesize are a defining factor of evolutionary dynamics,” she says.