Uranium Phytoremediation Project – Sunflowers and Arbuscular Mycorrhizal Fungi (AMF)

Purpose: Abandoned uranium mines are important sources of uranium soil contamination in the southwestern United States, with Native American lands being particularly exposed and of great concern. Phytoremediation, the use of plants to remove or stabilize heavy metal soil contaminants, has been studied as a viable method for the remediation of such contaminated sites.

Phytoremediation has been shown to be even more effective upon the addition of arbuscular mycorrhizal fungi (AMF) to the roots of plants. Many mechanisms have been proposed to explain this relationship; however, less research has been done with the aim of characterizing these mechanisms. We posit that one proposed mechanism, the desorption of uranium from clay minerals in the soil via AMF organic acid exudation, is likely the main driver of this relationship between AMF inoculation and increased uptake of uranium. To investigate this hypothesis, we will grow sunflowers under the following parameters: the presence of clay or not; low, mid-range, and high concentrations of uranium; and the presence of AMF or not. We aim to add to the body of knowledge concerning AMF-assisted phytoremediation, which could also increase the efficacy of phytoremediation strategies in the field.

Plant species: Helianthus spp.

Participants: 
Laura Wasylenki, Ph.D
Nancy Johnson, Ph.D
Katherine Dunlap, undergraduate