This image is of a Perennial Ryegrass (Lolium perenne L.) fine-root (0.15 mm diameter) excavated from field soil. It shows the endomycorrhizal hyphae of the associated symbiotic root fungus. These fungi live in the cortical cells of the roots and send their hyphae out into the soil to acquire nutrients, while the plant provides it with carbohydrates. This association between roots and fungi provides the plant with greater tolerance to stress and increased access to essential nutrients like phosphorus. AFSRC scientists have the objective to determine the response of root morphology and function to phosphorus and nitrogen uptake/availability in the root zone, and the biological and geochemical mechanisms for increasing phosphorus availability to plants within a project titled Managing Biogeochemical Cycles and Rhizosphere Ecology for Sustainable Production of Appalachian Pasture and Amenity Grasses.