Observations on the Relationship Between Above- and Below-Ground Anthocyanin Production in Galax urceolata (Poir.) Brummitt Growing in Sun-Exposed and Shaded Locations


Howard S. Neufeld

Additional Authors:

Derick B. Poindexter, Paula F. Murakami Paul G. Schaberg


March 2011


galax, anthocyanin

ABSTRACT Galax urceolata (Diapensiaceae) is a common evergreen herb of southern Appalachian forests. During the fall and winter, leaves of plants in high light produce substantial amounts of anthocyanins. Oddly, rhizomes in these plants also accumulate anthocyanins. The purpose of this observational study was to identify seasonal trends in anthocyanin production in above- and below-ground tissues of Galax. We measured anthocyanins and chlorophyll in Galax using standard extraction and spectrophotometric procedures from plants in sun-exposed and shaded locations; one population at Mount Jefferson State Natural Area in fall 2007 and two at Grandfather Mountain in fall/winter 2008– 09. Rhizome carbohydrates (soluble sugars and starch) were measured from the Grandfather populations using high performance liquid chromatography. We found significantly more anthocyanins in leaves and rhizomes of plants from sun-exposed locations compared to plants from shaded locations, but no differences in carbohydrate concentrations. Starch levels declined significantly through the fall/winter of 2008–09, while soluble sugars, such as sucrose, raffinose, and fructose, increased. Rhizomal anthocyanins were distributed throughout the entire cross-section except for the vascular tissues, whereas in petioles and leaves, they were restricted to the epidermal or subepidermal layers. Rhizomal anthocyanins often concentrated around lateral roots as they penetrated the cortex. These results contradict the paradigm that light is always required for anthocyanin production, and suggest the possibility of some form of communication between leaves and rhizomes with respect to anthocyanin content, although the nature of that signal is unknown. At this time, the adaptive significance of below-ground anthocyanins in Galax remains unresolved.