Document: MAT-3-58-40

Production of the arbuscular mycorrhizal fungal protein glomalin: The role of host plant species.

RILLIG, M.C.* ¹, S.F.WRIGHT ² and V.EVINER ³

University of Montana, Missoula, MT 59812 USA ¹
USDA-ARS, Beltsville, MD 20705 USA ²
University of California, Berkeley, CA 94720 USA ³

Abstract:
Arbuscular mycorrhizal fungi (AMF) are known to produce a glycoprotein, glomalin, which is deposited into soil. The protein has been shown to be involved in soil aggregate stabilization and is typically found in soils in amounts of several milligrams per gram of soil. Factors controlling the production of this crucial protein are almost completely unknown, but are hypothesized to include the AMF species, the host plant species and its carbon supply, and the soil environment. To test if host plant species can influence glomalin concentrations in soil, we grew eight plant species (including four grasses, two forbs, and two legumes) in monocultures in the field at the University of California Hopland Research and Extension Center, located in northern California. The soil concentrations of glomalin (immunoreactive fraction and total protein fraction) differed significantly among the eight host species, indicating that plant species may exert an important control on glomalin production. Since glomalin is tightly correlated with soil aggregate water stability in these grasslands, our results also suggest that plants can influence soil structure (and hence soil biota and processes) via their arbuscular mycorrhizal symbionts.

Keywords: arbuscular mycorrhiza, soil structure, glomalin

This abstract is being presented at: 3:30 PM in session:
MYCORRHIZAL FUNGI