Elizabeth Porter
The response of twelve prairie plant species to AMF isolated from a remnant prairie and an old field community
BSES Senior Research 2004

The soil community plays an important role in the maintenance of diversity in a plant community (Bever et al 1997). One component of the soil community is arbuscular mycorrhizal fungi (AMF). AMF transfer soil nutrients to associated host plant roots in exchange for carbon.

The relationship between AMF species isolated from prairie and old-field communities and their ability to promote the growth of prairie plants was explored. Specifically, we chose to evaluate the response of twelve prairie plant species that represent four families (Grass, Legume, Lily, and Composite) and a range of successional stages (early and late) to AMF collected in old-field and prairie environments in a greenhouse study. We expected that early successional plants would grow best in sterile soil or in soil inoculated with S. fulgida or G. claroideum, which were collected from old-field sites at the Kankakee Sands. We further expected that late successional plants would have greater biomass in live soil than sterile soil but grow best in the soil inoculated with S. pellucida or G. claroideum, which were collected from prairie sites.

We found that the Legume, Lily, and Composite families were not sensitive to the soil treatments and therefore saw no growth differences between the infected plants and non-infected plants. This result is surprising and counter to preliminary results on these species. The growth of these plants may have been limited by the high level of P found in the Kankakee Sands soils and by root crowding. The Grass family demonstrated a growth difference within soil treatments and by successional stage. The grasses generally grew better with AM fungi. The late successional grasses responded best to S. fulgida collected from the old field, while the early successional grasses responded best to G. claroideum collected from the prairie site. The results of this study indicate that different grasses from different successional stages have a variety of responses to AMF.