Project Number: 1935-12000-010-00
Project Type: Appropriated

Start Date: Apr 06, 2006
End Date: Apr 05, 2011

Objective:
Determine key cellular events and morphological changes that allow for the completion of the life cycle of arbuscular mycorrhizal fungi in the absence of a host plant. Develop a practical and inexpensive arbuscular mycorrhizal fungus inoculum production system for utilization by the small conventional farm, organic farm, and nursery. Determine the contribution of arbuscular mycorrhizal fungi to carbon sequestration in agricultural soils will be enhanced through contributions to the carbon sequestration database in the GRACEnet project.

Approach:
Determine key cellular events and morphological changes that allow for the completion of the life cycle of Arbuscular mycorrhizal (AM) fungi in the absence of a host plant. Expose spores of AM fungi to root exudate and extract fractions to stimulate metabolic pathways normally expressed only in intraradical hyphae. The in vitro culture system, coupled with bioassays we have developed, enable observation of changes in hyphal morphology. Monitor the metabolic response of AM fungi to experimental treatments with metabolic markers such as glucose uptake and triacylglyceride synthesis. Develop a practical and inexpensive inoculum production system for utilization in agriculture. Test the efficacy of fungi propagated in this system, develop greenhouse culture regimes to ensure colonization of vegetable seedlings, modify inoculum production media to produce an inoculum formulation conducive to field application via farm machinery, and demonstrate the efficacy of the inoculum in the field. Determine the contribution of AM fungi to carbon sequestration in agricultural soils. Measure glomalin concentrations in soil cores from organic and conventionally farmed plots of The Rodale Institute's Farming System Trial.