My research focuses on population genetics of fungal plant pathogens, population biology, forest health, forest pathology, and diversity and conservation efforts of native plants. Our lab is interested in understanding complexity of host-pathogen-vector interactions and its associated microbial communities within the phytobiome across both introduced and native ranges. Increases in both native and introduced pathogens as a result of climate change have provided numerous opportunities in basic and applied research. My program’s main goal is to utilize novel genetic and genomic tools to integrate molecular data into pragmatic management decisions and provide solutions for preservation of biodiversity, conservation of native species and overall tree improvement programs. In addition, my research goal is to contribute to hunger eradication efforts on the African continent by preserving biodiversity of indigenous and nutritional plants adapted to climate change. This will not only provide regional food security, but will promote science literacy, and recruit and educate the next generation of science ambassadors in sub-Saharan African countries.

Host-Pathogen-Vector Interactions
My primary research centers on understanding host-pathogen-vector interactions with a focus on Thousand Cankers Disease (TCD) complex. The fungus, Geosmithia morbida, vectored by the walnut twig beetle, Pityophthorus juglandis, has been associated with disease outbreaks in walnut trees, Juglans spp., known as TCD. Read More The unique relationship of the host-pathogen-vector complex can result in significant evolutionary pressure for the pathogen, thus shaping the genome of G. morbida in unique ways that have not yet been documented in fungi. We are investigating a genome-enabled approach focused on G. morbida that will provide a better understanding of the biology of the pathogen involved in TCD and identify candidate genes and functions required for pathogenesis. Most evolutionary studies have focused on pathogens of crops that are not insect vectored, making this research a unique contribution in determining co-evolutionary history, and shedding light on emergence of new pathogenic fungi that continue to be a threat to fruit, nut, and forest trees worldwide.

Phytobiomes of Trees
The complexity of host genetics and its associated microbial communities within the phytobiome (plant itself + environment + micro- and macro-organisms living in, on, or around the host plant) can vary across a plant’s introduced and native ranges, resulting in higher ecosystem multifunctionality and functional redundancy. Host phytobiome plays an important role in host plant defenses, nutrient acquisition, and stress tolerance, serving critical functions in the interaction between plants and the environment. Using walnut trees as a non-model system, we are evaluating the impact of the complex disease system, Thousand Cankers Disease (TCD), on host genetic diversity and examining the correlation between phytobiome and disease severity in both introduced and native ranges.

Conservation Genetics and Biodiversity
An additional component of my research program focuses on conservation efforts of native trees, preservation of biodiversity in North American forests, and overall forest and tree health and protection on a global scale. We intend to devote research and teaching efforts to limit the impact of forest diseases and provide an understanding of the evolutionary dynamics, diversity and disease ecology of environmentally, socially and economically, significant trees. Read More Currently, our lab is involved in a number of conservation genetics projects focused on endangered and endemic plants in the U.S.A. and Ghana, Africa, including food security crops. In that capacity, we are involved with conservation efforts of Pityopsis ruthii, Ruth’s Golden Aster, an endangered species from the Hiwassee and Ocoee Rivers in Tennessee; Helianthus verticillatus (whorled sunflower), federally endangered plants species in Tennessee, Alabama and Georgia; and the biodiversity and preservation of an antimalarial plant endemic to Ghana, Cryptolepis sanguinolenta.

Population Genetics
In my lab, we have a number of projects related to population biology/genetics of native and/or economically important plants, as well their pathogens. We are interested in a number of different factors including, but not limited to, understanding the basic biology of the host-pathogen interactions, host-pathogen coevolution, how spatial distribution influences genetic diversity, their population structure and patterns of gene flow. Using these tools can expand our understanding of the ecological and evolutionary dynamics and elucidate historical processes that are a result of the past or current disease outbreak(s).

“Tell me and I forget. Teach me and I remember. Involve me and I learn.” The best way to share your passion is to teach and educate others. That is why I am involved in STEM outreach for both high school and college students. An undergraduate research opportunity I was given as a student was the sole reason I continued my scientific exploration through further education. As a result, I became the person I am today – someone who loves science and loves sharing that passion, enthusiasm and inspiration with students, through both research and teaching. I am a firm believer that the best way to learn is to teach and that one’s education is never ending.

I strongly believe that a teacher is a role model, advisor, guide, inspiration, and someone who is fundamentally involved and entirely dedicated to their student’s success. A teacher leads by example, motivates and encourages students to be the best they can be, and to go beyond their limits and even their own expectations. I feel fortunate and humble that I am able to do a job where I can share my passion and enthusiasm while fostering the educational growth of students. Teaching is an incredible gift, but also an enormous responsibility. As a teacher and researcher, I would like to have the same impact on students that my teachers and role models have had on me. I would like to be the change and inspiration to improve the world we live in by supporting future generations of environmental stewards and scientists.

EPP 411 – Forest Insects and Diseases (3 credits)

EPP 531 – Special Problems in Entomology, Nematology, and Plant Pathology – Population Genetics (3 credits)

EPP 604 – Genomics of Forest Pest and Pathogens (3 credits; Co-teaching special topics class with Dr. Meg Staton)

EPP 604 – PopGen Journal Club (1 credit; Co-teaching special topics class with Dr. DeWayne Shoemaker)