Major adviser: Louise Egerton-Warburton, PhD
Research Interests: Mycorrhizal fungal community dynamics, fungus-mediated ecological processes, the role of symbiosis in early land plant evolution, tropical ecology, fungal genomic organization
My doctoral research focuses on the use of molecular genetic tools to investigate the composition of plant and fungal communities in the seasonally dry tropical forests of the Yucatan Peninsula in Mexico, and their interaction with the pervasive karst cave system underlying the forests.
One group of fungi of particular interest to me are the arbuscular mycorrhizal fungi (AMF). Belonging to the monophyletic Glomeromycota, all the fungi in this group form intimate relationships with plant roots, where they are given sugars by the plant in exchange for nutrients and water. This association is thought to have originated more than 400 million years ago, and to have been integral to the colonization of land by plants. AMF remain vital ecological components to this day, as around 75% of all plant species on earth depend on these relationships for healthy growth and development. These fungi are likely to play an especially important role in the seasonally dry tropical forests, where their ability to forage for water and nutrients may enable certain canopy tree species to remain evergreen throughout dry seasons. AMF communities are in turn likely to be impacted by the ability of some plant species to access water reserves in the caves. To begin to understand these complex biological and geohydrological relationships, I am employing DNA barcoding and both Sanger and high throughput Illumina sequencing to identify the species of plants accessing below ground water and the species of AMF associated with plants in the forests of the Yucatan, and to examine the effects of host plant species, annual precipitation, and seasonality on AMF communities.
I am also investigating communities of wood decaying fungi in these forests. The degradation of recalcitrant compounds in wood, like lignin and other polyphenolics, is an essential process in the global carbon cycle, and is also relevant in industrial processes including maximizing output in biofuels generation. I am using a DNA barcoding approach to identify the fungal species accessing lignin substrates placed in situ in Mexican seasonally dry tropical forests, and metagenome sequencing to identify candidate genes encoding ecologically or industrially significant lignolytic enzymes.