My research focuses on population genetics of fungal plant pathogens, population biology, forest health, forest pathology, and diversity and conservation efforts of native plants. Increases in both native and introduced pathogens as a result ofclimate 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.

Research Focus

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, Geosmithiamorbida, vectored by the walnut twig beetle, Pityophthorusjuglandis, has been associated with disease outbreaks in walnut trees, Juglans spp., known as TCD. 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.

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. Currently, our lab is involved in a number of conservation genetics projects focused on endangered and endemic plants in the U.S. and Ghana, Africa. In that capacity, we are involved with conservation efforts of Pityopsisruthii, 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, Cryptolepissanguinolenta.

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/pathogeninteractions, 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).


Extension and outreach focus

Benjamin Franklin once said, “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.

In that capacity, I am involved in number of projects that involve presentation to high school/college students related to forest pathology and conservation research, workshops, seminars and other outreach opportunities:

  1. USAID-BHEARD(Borlaug Higher Education for Agricultural Research and DevelopmentProgram)/University of Tennessee/University of GhanaGrant Writing Workshop, University of Ghana/West Africa Centre for Crop Improvement, Accra, Ghana(Spring 2018)I organized and helped teach a two-day long workshop that involves interactive training for graduate students, staff and faculty that focuses on teaching how to write a successful grant application. Topics included funding resources, standard components of grant proposal, common mistakes, and how to avoid them.
  2. USAID-BHEARDMolecular Workshop and Professional Development. University of Ghana/West Africa Centre for Crop Improvement, Accra, Ghana (Summer 2017)I helped teach a weeklongworkshop designed for technical staff and students from Ghana to improve laboratory and molecular skills, as well as to develop/improve new professional skills (research ethics, laboratory organization, scientific writing).
  3. Big Orange STEM Saturday. University of Tennessee, Knoxville, TN (Spring 2017)An annual event hosted by UTK libraries for high school and new undergraduate students interested in pursuing STEM disciplines. I presented work to students related to forest pathology research and conservation efforts.
  4. Third Annual Women inSTEM Research Symposium. University of Tennessee, Knoxville, TN (Spring 2017) Volunteer judge – oral presentations.Students, postdoctoral fellows, faculty, and staff presenttheir research findings from each of the 50+ science, technology, engineering, and math (STEM) fields. I was a faculty member judge for the oral presentations.
  5. USDA-NIFA-Women and Minorities in Science, Technology, Engineering and Mathematics Outreach at the University of Tennessee, Knoxville (Summer 2016)This was a two-day camp titled – Fostering aGIRLculture: a girls STEM camp solving the Grand Challenges of the 21st Century. I presented a lecture related to epidemiology and worldwide distribution of vector-borne diseases; co-organized and participated in two different modules – soil diversity and epidemiology with a focus on Zika.
  6. Thirteenth Annual Tennessee Louis Stokes Alliance for Minority Participation (LSAMP) Research Conference – Undergraduate Research/Graduate School (URGS) Fair. University of Tennessee, Knoxville (Spring 2016)Two-day program organized and aimed to increase the enrollment and graduation rate of underrepresented students in STEM disciplines. The program is focused on recruiting underrepresented students to pursue science or engineering as a career, improve the quality of the learning environment for underrepresented science and engineering students at all schools and ensure that a larger number of undergraduate students are prepared to enter graduate programs. As a faculty member, I represented the EPP department, interacted with students, provided information regarding our current research projects and recruited students to apply to our graduate program.
  7. Pre-College Upward Bound (PCUB) Project, University of Tennessee, Knoxville (Summer 2014-current)This was a six weeks long teaching and research program designed to help low-income, potential first-generation college students to graduate from high school and to enroll in a postsecondary institution of their choice that aligns well with their educational and professional goals. Since 2014, I have supervised and mentored 6 high school students from east Tennessee and I plan on continuing that in the future.
  8. GadgetGirlsAdventuresinSTEM, University of Tennessee, Knoxville (Summer 2012)I provideda day of hands-on science to middle school aged girls. Co-taught a module entitled “Cracking the Code” that teaches the central dogma of molecul arbiology (DNA to RNA to protein) with pencil, paper and beads to make a “protein” bracelet.

Teaching focus


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

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, 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.

Denita Hadziabdic Guerry

Assistant Professor
main office (865) 974-7135
fax (865) 974-4744

370 Plant Biotechnology Building
2505 EJ Chapman Drive
Knoxville, TN 37996-4560

Graduate program concentrations (pick 1-3 of these)
Bioinformatics, Genomics, and Molecular Interactions
Organismal Biology, Ecology, and Systematics

Areas of expertise
Forest health and forest pathology, population genetics of fungal pathogens, population biology, genetic diversity and conservation of native plants

B.S., Biology, Fairmont State University (1979)
M.S. Plant Pathology, West Virginia University (1982)
Ph.D., Plant Pathology, North Carolina State University (1987)

Creative Art Microscope image

Research questions in our laboratory

  • How and why do disease outbreaks occur?
  • How do fungal pathogen disperse across wider geographical ranges, and how dothose processes influence species genetic architecture?
  • How can we utilize novel genomic approaches to develop molecular diagnostic tools for invasive pathogens?
  • What genomic changes occur in a host during fungal invasion?
  • How dobiotic and abiotic factors serve as a predictor of disease outbreaks?
  • What integrative approaches can be utilized for development of conservation and best management practices of native species in the U.S. and globally?

Current lab members

  • MeherOny (M.S. student)

Selected Publications

Students and postdocs from Hadziabdic lab are underlined.


  1. Edwards TP, Trigiano RN, Wadl PA, Ownley BH, Windham AS, Hadziabdic D (2017) First report of Alternaria alternata causing leaf spoton Ruth’s Golden Aster (Pityopsisruthii) in Tennessee. Plant Disease:101(2): 383
  2. Edwards TP, Trigiano RN, Wadl PA, Ownley BH, Windham AS, Hadziabdic D (2017) First report of Alternaria alternata causing leaf spoton whorled sunflower (Helianthus verticillatus) in the southeast United States. Plant Disease 101(4): 632 Co-author and major advisor; contributed to manuscript preparation.
  3. Mantooth K*, Hadziabdic D*, BoggessS, WindhamM, Miller S, CaiG, Spatafora J, ZhangN, Staton1 M, Ownley, Trigiano R (2017) Confirmation of independent introductions of an exotic plant pathogen ofCornusspecies, Disculadestructiva, on the east and west coasts of North America and subsequent population bottlenecks. PlosOne 12(7) : e0180345
  4. Oren E, Klingeman W, Gazis R, Moulton J, Lambdin P, Coggeshall M, Hulcr J, Seybold S, Hadziabdic D (2017) A novel molecular toolkit for rapid detection of the pathogen and primary vector of Thousand Cankers Disease. PlosOne(In Press).
  5. Blood B, Klingeman W, Paschen M, Hadziabdic D, Couture J, Ginzel M (2017) Behavioral responses of Pityophthorusjuglandis(Coleoptera: Curculionidae: Scolytinae) to volatiles of black walnut and Geosmithiamorbida, the causal agent of Thousand Cankers Disease. Environmental Entomology (In Press).


  1. Daniels DA, NixKA, Wadl PA, Vito LM, Wiggins GJ, WindhamMT, Ownley BH, Lambdin PL, Grant JF, Merten P, KlingemanWE, Hadziabdic D (2016) Thousand Cankers Disease Complex: A forest health issue that threatens Juglans species across the U.S. Forests 7(11):260. DOI: 10.3390/f7110260.
  2. Amissah JN, Wadl PA, Hadziabdic D, Boggess SL, Trigiano RN (2016) Characterization of thirteen microsatellite loci from the West African antimalarial plant Cryptolepissanguinolenta. J. Med. Plants Res. 10:183-187. DOI: 10.5897/JMPR2016.6047.
  3. Trigiano RN, Bernard EC, Hadziabdic D, Dattilo AJ, Wadl PA (2016) First report of powdery mildew on whorled sunflower (Helianthus verticillatus) caused by Plant Dis. 100 (5): 1017.
  4. RinehartTA, Hadziabdic D, Wadl PA, Trigiano RN (2016) Molecular tools for studying genetic diversity in plant pathogens. In: Ownley, B.H. and R.N. Trigiano, eds. Plant Pathology, Concepts and Laboratory Exercises, 3rd CRC Press, Boca Raton, FL. pp 517-539.


  1. Dean D*,Wadl PA*, Hadziabdic D*, Klingeman WE, Ownley BH, Rinehart TA, Dattilo AJ, Scheffler B, Trigiano RN (2015) Analysis of genetic diversity and population structure for the US native shrub Viburnum rufidulum in Tennessee and Kentucky. J. Amer. Soc. Hort. Sci. 140 (6): 523–531. 2015.
  2. Hadziabdic D*, Wadl PA*, Staton ME, Klingeman WE, Moulton JK, Pscheidt JW, Wiggins GJ, Grant JF, Lambdin PL, Windham MT, Faccoli M, Merten PR, Trigiano RN (2015) Development of microsatellite loci in Pityophthorusjuglandis, a vector of thousand cankers disease in Juglans Conserv. Genet. Resour. 7 (2): 431-433. DOI: 10.1007/s12686-014-0388-0. * Equal author contributors.


  1. Boggess SL, Wadl PA, Hadziabdic D, Scheffler B, Windham AS, Klingeman WE, Trigiano RN (2014) Characterization of 12 polymorphic microsatellite loci of Pityopsisgraminifolialatifolia. Conserv. Genet. Resour. 6 (4): 1043-1045. DOI: 10.1007/s12686-014-0282-9.
  2. Wiggins GJ, Grant JF, LambdinPF, Merten P, Nix KA, Hadziabdic D, WindhamMT (2014) Discovery of walnut twig beetle, Pityophthorusjuglandis, associated with forested black walnut, Juglans nigra, in the eastern U.S.Forests5: 1185-1193. Communication DOI:10.3390/f5061185.
  3. Hadziabdic D, Vito L, Windham M, Pscheidt J, Trigiano R, Kolarik M (2014) Genetic differentiation and spatial structure of Geosmithiamorbida, the causal agent of thousand cankers disease in black walnut (Juglans nigra). Current Genetics. 60: 75-87. DOI: 10.1007/s00294-013-0414-x. (Published online in 2013).
  4. Hadziabdic D, Windham M, Baird E, Vito L, Cheng Q, Grant J, Lambdin P, Wiggins G, Windham A, Merten P, Taylor G (2014) First report of Geosmithiamorbida in North Carolina: the pathogen involved in thousand cankers disease of black walnut. Plant Dis. 98: 992.


  1. Trigiano RN, Wadl PA, Dean D, Hadziabdic D, Scheffler BE, Runge F, Telle S, Thines M, Ristaino J, Spring O (2012) Ten polymorphic microsatellite loci identified from a small insert genomic library for Peronosporatabacina. Mycologia 104 (3): 633-640. DOI: 10.3852/11-288.
  2. Hadziabdic D, Wang X, Wadl PA, Rinehart TA, Ownley BH, Trigiano RN (2012) Genetic diversity of flowering dogwood in the Great Smoky Mountains National Park. Tree Genet. Genomes 8: 855-871. DOI: 10.1007/s11295-012-0471-1.
  3. Hadziabdic D, Wadl PA, Vito LM, Boggess SL, Scheffler BE, Windham MT, Trigiano RN (2012) Development and characterization of sixteen microsatellite loci for Geosmithiamorbida, the causal agent of thousand canker disease in black walnut (Juglans nigra). Conserv. Genet. Resources 4: 287-289. DOI: 10.1007/s12686-011-9526-0.


  1. Wadl PA, Dean D, Li Y, Vito LM, Scheffler BE, Hadziabdic D, Windham MT, Trigiano RN (2011) Development and characterization of microsatellites for switchgrass rust fungus (Pucciniaemaculata). Conserv. Genet. Resources 3: 185-188.
  2. Wadl PA, Reed SM, Hadziabdic D (2011) Production of haploid tobacco and potato plants using anther culture. In: Trigiano, R.N. and D.J. Gray, eds. Plant Tissue Culture, Development and Biotechnology, CRC Press, Boca Raton, FL.
  3. Hadziabdic D, Reed SM, Wadl PA (2011) Haploid cultures. In: Trigiano, R.N. and D.J. Gray, eds. Plant Tissue Culture, Development and Biotechnology, CRC Press, Boca Raton, FL.
  4. Trigiano RN, Vito LM, Windham MT, Boggess SL, Hadziabdic D (2011) Direct shoot organogenesis from leaf explants of chrysanthemum and African violets. In: Trigiano, R.N. and D.J. Gray, eds. Plant Tissue Culture, Development and Biotechnology, CRC Press, Boca Raton, FL.

For complete list of publications please visit my

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