Extreme environments are known to exert strong selection on organisms, leading to population-level differentiation at local scales. This research will examine local adaptation in symbiotic fungi to serpentine soil, an extreme environment with high heavy metal content that is known to have caused evolutionary changes in plants. Symbiotic fungi collected from serpentine and non-serpentine oak forests in northeastern Portugal will be grown in both soil types in a controlled reciprocal experiment that will elucidate the ability of fungi to tolerate serpentine environments. Results from this study will provide critical new insights into the ecology and evolution of symbiotic fungi and plants in extreme environments, and they will add to our understanding of serpentine ecosystems. Broader impacts of this study include graduate training and relevance to biological conservation, bioremediation, and restoration. Serpentine soils host multiple plant endemics, many listed as threatened. Providing information on the symbiotic fungi occurring in these habitats will be critical for informing and guiding biodiversity conservation and management measures. This study will also provide valuable information on how fungi cope with heavy metal hotspots. This is extremely useful for the field of bioremediation, since the ability of heavy metal tolerant symbiotic fungi to withstand polluted areas (such as mine waste deposits) has major implications for the establishment and maintenance of plant communities, which then affects recovery of entire terrestrial ecosystems. Also, fungi living in serpentine soils are excellent candidates for model systems for investigating mechanisms of heavy metal tolerance.
