PARENT SESSION
Poster Session 23: Soil Ecology
Wednesday, August 10, 5:00 PM - 6:30 PM, Exhibit Hall 220 A-E, Level 2, Palais des congrès de Montréal
Identities of plant species and functional groups determine spore communities of mycorrhizal fungi in grassland and agriculture.
Picone, Christopher*,1, 1 Fitchburg State College, Fitchburg, MA, USA
ABSTRACT- Sustainable agriculture requires mixtures of different plant species or functional groups. By understanding how different plants affect beneficial soil microbes, we might choose crop combinations that promote healthier soil communities. In this study, communities of arbuscular mycorrhizal (AM) fungi were compared among 22 plant species in four functional groups: warm-season (C4) grasses, cool-season (C3) grasses, legumes, and composites. These plant groups dominate native grasslands and the agricultural systems found on them. Within each functional group, both annuals and perennials were compared, and plant species varied widely in their dependence on mycorrhizae. All species were inoculated with a homogenized soil containing a diverse community of AM fungi from native Kansas grasslands and farms. After plants senesced in their second year, I identified and quantified AM fungus spores produced with each plant species. The functional group of host plants determined the abundance of spores of some fungus species. Several Glomus species were most common with warm-season (C4) grasses, while members of the Gigasporaceae were most common with other functional groups. One species on Gigaspora was especially prolific with only one host species, the legume Illinois bundleflower (Desmanthus illinoensis). Other plant categories had no predictive value. In undisturbed pots of soil, annual plants fostered the same types of fungi as perennial plants, despite the fact that soil from annuals had much more available nitrogen. The dependence of a plant species on mycorrhizae had no relation to the abundance or identities of spores in its soil community. In sum, a host plant's functional group, or in some cases species identity, may be used to manage a community of mycorrhizal fungi.
Key words: arbuscular mycorrhizal fungi, functional group, sustainable agriculture, grasslands