Sikes Microbial Lab
Rates of Pathogen Accumulation in Introduced Host Plants
Enemy release is a hypotheses for both the prolific spread of alien species and increased productivity of economically important species when grown in new locations. This research uses the unique and extensive record of New Zealand plants and pathogens to determine if the rate of pathogen accumulation in introduced plants is determined by factors such as host species range and abundance, extent of human use, relatedness of native species and the global pool of known pathogens.
Utilizing Natural Soil Biotic Communities to Enhance Ecosystem Resilience and Recovery
Plant interactions with belowground organisms have emerged as major factors determining the structure and long-term stability of plant communities. Yet the vast diversity of this soil biota remains a largely untapped resource in ecosystem conservation and restoration. I'm using 454 pyrosquencing and culturing to determine differences in multiple soil fungal groups among native FL scrub sites, disturbed sites and those converted to pastures. I have established field experiments where I add back in specific fungal groups from native sites or sites to be restored ("target"). Addition of specific fungi alters the germination rates of native plants we seeded into degraded sites, but benefits depend on the plant species, the origin of fungi added and the site type. This research will establish a conceptual framework and prototype for the use of native soil biota to help preserve and restore ecosystems.
Interactive Assembly of Fungal and Plant Communities
This project utilizes soils, plants and fungi from native Florida scrub, disturbed scrub and converted pastures at the Archbold Biological Station in Florida. The plant species are all grasses, two native and one non-native. Fungal endophytes were isolated from roots at the sites. In each pot we vary the initial fungal community (native, disturbed or pasture) and added one plant species. 2 weeks later we add the other fungal communities and plant species. The goal is to determine if the timing and identity of plant and fungal arrival affects the ultimate community that establishes. Early data indicates that the invasive plant thrives when native or disturbed fungi are introduced first, but does poorly when pasture fungi are first. As a further sign of this negative feedback, it does very poorly when it is the first plant. This data will be used in restoration of native scrub in disturbed and converted pasture sites in the field.
The Role of Mycorrhizal Fungi in Primary Succession
I am studying how mycorrhizal fungal communities and function change during primary sand dune succession as well as the potential these changes have to effect broader patterns of ecosystem development such as plant succession. I have explored these patterns in lacustrine dunes of the Great Lakes including two sites in the US (Indiana Dunes National Lakeshore and Wilderness State Park, MI) and one site in Canada (Pinery Provincial Park). I am using molecular techniques to characterize mycorrhizal fungal communities in the field as well as several other parameters. I also conducted manipulative experiments in the greenhouse to determine what the relative importance of arbuscular mycorrhizal fungal succession is to plant species compared to other abiotic changes in soils.