Current Research Interests 

Amanita phalloides, or the ‘death cap’, is a deadly toxic and invasive ectomycorrhizal fungus introduced from Europe to the United States. In California, A. phalloides has spread to the endemic coastal oak woodlands, where death caps appear in high densities, associated with native Quercus agrifolia. The death cap belongs to the clade of “lethal amanitas”, widely known for producing toxic specialized metabolites (SMs), including amatoxins and phallotoxins capable of inhibiting eukaryotic RNA polymerase II and microfilament dynamics. The death cap’s infamous toxins, and many undescribed peptides, experience strong natural selection in both ranges, but their ecological function are still shrouded in mystery. In my PhD, I am investigating how A. phalloides’ SMs mediate interactions with potentially antagonistic organisms to ultimately uncover the ecological dynamics of its invasion in California. The death cap system offers a unique opportunity to explore the purpose of mushroom chemistry in nature and describe the mechanisms of successful and persistent invasive non-pathogenic fungi. [Left photo by: Mark Unger]. 

The global export of commercial trees has introduced the genus Pinus and its fungal symbiont, Amanita muscaria, throughout the southern hemisphere. The invasion of Pinus into native habitats is partially facilitated by its fungal partners but A. muscaria can also spread independently in association with native trees. In the fall of 2022, I attended a three-week NSF IRES sponsored graduate workshop hosted by the Forestry and Agricultural Biotechnology Institute (FABI) of South Africa focused on the ecological and evolutionary consequences of plant-fungal co-invasions. Since this workshop, as large collaborative group of workshop organizers and attendees from USA and FABI, we have used natural history and genomic data to investigate the biogeographic and phylogenetic origin of invasive A. muscaria in South Africa and the consequences of its invasion on genetic diversity and evolution of SMs.  

Past Research

As we continue to employ the widespread use of fungicides, fungal and oomycete pathogens are becoming increasingly resistant and, in turn, are threatening national and global food security. After completing my undergraduate degree, I joined a North Carolina State University plant pathology extension lab located in Waynesville, NC. Our main research objectives focused on testing the efficacy of conventional and biological fungicides against pervasive fungal and oomycete pathogens of tomatoes, cucurbits, and peppers.  While in this position, I assisted with large-scale fungicide field and greenhouse trials, as well as molecular analyses to understand the spread and distribution of Phytophthora  outbreaks in regional ornamental plant nurseries. 

The Roan Highlands, located between Tennessee and North Carolina along the Appalachian trail, contains a series of endemic and threatened grassy bald ecosystems. These largely treeless landscapes are home to native grasses, sedges, and rare herbaceous plants. Due to heavy recreational use and climate change, the plant communities are threatened by invasive species and forest encroachment. To combat this issue, a long-term management program, mainly consisting of mowing Rubus spp., has been maintained since the late 1980s. Inspired by a survey conducted before active management began, I designed my undergraduate research to compare plant communities between sites subjected to different management regimes (frequency and type) to better understand how active management shapes plant community composition through time. Our results suggest an increase in graminoid coverage within frequently managed sites and highlight the importance of continued preventative strategies and restoration efforts to conserve the threatened habitat. [Pictures: Travis Boardley]