Tracie M. Jenkins
Associate Professor of Applied Insect Genetics
Address: Department of Entomology
Phone: (770) 412-4093
GENE 3000, Evolution, 4 credits, Spring Semester, (syllabus)
GENE 3200, Genetics, 4 credits, Fall Semester, (syllabus)
HORT 4800, Biotechnology, 3 credits, Fall Semester, (syllabus)
PGEN 3580, Plant Genetics, 3 credits
AESC 4950, Undergraduate Research in Agricultural and Environmental Science,
2–3 credits, Fall and/or Spring, TBA with each student
AESC 4960, Special Problems in Agricultural and Environmental Science,
2–3 credits, Fall and/or Spring, TBA with each student (syllabus)
|Tyler Eaton, Technician|
Overview: The genetics of insect pests.
The overall purpose of the research in my lab is to understand the natural history of urban, horticultural and invasive insect pests through the use of DNA marker technology and the application of population and evolutionary genetic theory. This genetic characterization of insect pest populations can then be used to develop effective insect pest management strategies as well as provide the basis for understanding insect pest efficacy test results.
Photo by Dan Suiter, UGA
Megacopta cribraria (F.) (Hemiptera: Heteroptera: Plataspidae) is a true bug known previously only in the Old World from India and Pakistan to China, Korea, Japan and Malaysia to Australia where it is often a pest on soybeans and other legumes. It made its first appearance on the North American continent in mid-October 2009 when it was recovered from several northeastern counties in Georgia. The bug was confirmed to be Megacopta cribraria from morphological and molecular characterization (Jenkins et al. 2010). DNA data also indicated that it was carrying a gamma-Proteobacterium, an endosymbiont which has been linked to the bug’s normal growth and development as well as increased fecundity and pest status (Jenkins et al. 2010).
Studies in this lab are ongoing to determine its country of origin, genetic diversity and dispersal pattern in Georgia as well as to develop a population genetic baseline for M. cribraria against which future studies can be compared.
Black Carpenter Ant, Camponotus pennsylvanicus (Hymenoptera: Formicidae)
Camponotus species are serious pests that cause billions of dollars in wood damage annually in the United States. They, unlike termites, do not eat wood but excavate and nest in it. The black carpenter ant, Camponotus pennsylvanicus (DeGeer), is a prevalent structural pest of the eastern and central United States; and, may even be the most common carpenter ant pest east of the Mississippi River. These ants will establish primary or satellite colonies in dry, sound wood throughout a structure such as in support timbers, roofs, shingles, garages, window frames and sills. Thus, in the southeastern United States the growing urbanization, which includes building near forested areas, and ecological changes due to warming trends are likely exacerbating the problem of C. pennsylvanicus infestations. In collaboration with Dr. Dan Suiter, UGA Entomology, and using an integrative protocol, which includes field work, behavioral studies and DNA marker technology, my lab has begun a longitudinal study the purpose of which is to understand the intra- and intercolony structure of 20 C. pennsylvanicus colonies. We expect to illuminate intra- and intercolony spatial and temporal gene flow that will help interpret efficacy test results.
Flea beetles (Coleoptera: Chrysomelidae)
Flea beetles are serious pests of horticultural and agricultural plants. Our overall purpose is to understand the insect host-plant interactions of flea beetles that attack plants in the Onagraceae and Lythraceae families in order to develop effective control strategies. My lab in collaboration with Dr. Kris Braman, UGA Entomology, is conducting a longitudinal study, the objectives of which are to determine the molecular taxonomy, gene flow, and phylogeny and insect-host plant co-evolution of beetles in the genus Altica. Our initial results show host plant specificity, a relationship between morphology and DNA character states, unrestricted gene flow across states and ecoregions, and possible positive assortative mating.
Termites (Isoptera: Rhinotermitidae)
Accurate species identification underlies all termite field studies and population genetic research. With more than 170 species of termites in Peninsular Malaysia, it has been challenging to elucidate proper taxonomic records among the species, particularly within the family Termitidae. This lack of taxonomic clarity hampers many studies on termites in this area of the world. My lab in collaboration with Dr. Chow-Yang Lee, School of biological Sciences, Universiti Sains Malaysia, Penang, Malaysia, is presently studying the taxonomy of species within the family Termitidae. Individual termites are first identified to species and or genus by morphometric characters. Taxonomic fidelity from morphometric characters is then determined by distance matrix and character-state phylogenetic analyses of sequence data.
Termite mounds in Northern Australia
Gene flow, natural history
Coptotermes gestroi, the Asian subterranean termite (AST), C. formosanus, the Formosan subterranean termite (FST), and R. flavipes, the eastern subterranean termite (EST), are economically important exotic and indigenous structural and agricultural pests that have become established in many areas of the world including the United States. Current collaborative research with Brian Forschler, UGA Entomology, Dan Suiter, UGA Entomology, and Susan Jones, OSU Entomology, concerns using DNA data to determine the phylogenetic relationships of AST and FST collected in indigenous locations within Asia and Southeast Asia as well as from areas of introduction in South America and the United States and its territories. The overall purpose of this research is to use optimality criteria encompassing phenetic and cladistic assumptions coupled with phylogeographic theory and historical data to identify where exotic termites originate and their mechanism of dispersal. This is a crucial step for developing possible interdiction policies to curtail future introductions of these destructive insect species.
I serve as a mentor for the Young Scholars Program in the College of Agricultural and Environmental Sciences. The Young Scholars Program is committed to providing the brightest of our High School Students the opportunity to develop scientific skills by doing research in one of the working research labs on campus. I also serve as a resource for science fair participants and/or as a judge for science fair projects at the school, regional and state level.
Ruberson J. R., Takasu K, G. D. Buntin, J. E. Eger, Jr., W. A. Gardner, J. K. Greene, T. M. Jenkins et al. 2012. From Asian curiosity to eruptive American pest: Megacopta cribraria (Hemiptera: Plataspidae) and prospects for its biological control. Appl. Entomol. Zool. DOI: 10.1007/s13355-012-0146-2. PDF
Jenkins, T. M. and T. D. Eaton. 2011. Population genetic baseline of the first plataspid stink bug symbiosis (Hemiptera: Heteroptera: Plataspidae) reported in North America. Insects 2: 264-272. PDF
Jenkins, T.M., M. L. Wang, and N. A. Barkley. 2011. Microsatellite markers in plants and insects Part II: Databases and in Silico tools for microsatellite mining and analyzing population genetic stratification. Genes, Genomes, Genomics 5: 1-11. PDF
Eger, J. E., Jr., L.M. Ames, D. R. Suiter, T. M. Jenkins, D. A. Rider, and S. E. Halbert. 2010. Occurrence of the Old World bug Megacopta cribraria (Fabricicus) (Heteroptera: Plataspidae) in Georgia: a serious home invader and potential legume pest. Insecta Mundi 0121: 1-11. PDF
Jenkins, T.M., T. D. Eaton, D. R. Suiter, J. E. Eger, Jr., L. M. Ames, and G. D. Buntin. 2010. Preliminary Genetic Analysis of a Recently-Discovered Invasive True Bug (Hemiptera: Heteroptera: Plataspidae) and Its Bacterial Endosymbiont in Georgia, USA. J. Entomol. Sci. 45(1): 1-2. PDF
Jenkins, T. M., S. K. Braman, Z. Chen, T. D. Eaton, G. V. Pettis, and D. W. Boyd. 2009. Insights into flea beetle (Coleoptera: Chrysomelidae: Galerucinae) host specificity from concordant mitochondrial and nuclear DNA phylogenies. Ann. Entomol. Soc. Am. 102: 386-395. PDF
Ruhl, M. W., M. Wolf, and T. M. Jenkins. 2009. Compensatory base changes illuminate morphologically difficult taxonomy. Mol. Phylogenet. Evol. doi:10.1016/j=ympev.2009.07.036 PDF
Jenkins, T. M., T. D. Eaton, and Z. Chen. 2009. Altica litigata (Coleoptera: Chrysomelidae: Galerucinae) morphology: A backdrop for molecular phylogenetic comparisons. Res. Chrysomelidae. 2, 197-206. PDF
Wang, J. L., N. A. Barkley, and T. M. Jenkins. 2009. Microsatellite markers in plants and insects Part I: Applications of biotechnology. Genes, Genomes, Genomics 3, x-y. Invited Review PDF
Jenkins, T. M., S. C. Jones, C.-Y. Lee, B. T. Forschler, Z. Chen, G. Lopez-Martinez, N. T. Gallagher, G. Brown, M. Neal, B. Thistleton, and S. Kleinschmidt. 2007. Phylogeography illuminates maternal origins of exotic Coptotermes gestroi (Isoptera: Rhinotermitidae). Mol. Phylogenet. Evol. 42: 612-621. PDF
Lee, C.-Y., B. T. Forschler, and T. M. Jenkins. 2005. Taxonomic questions on Malaysian termites (Isoptera: Termitidae) answered with morphology and DNA biotechnology. Proceedings of the 5th International Conference on Urban Pests, Singapore.
Jenkins, T. M., R. E. Dean, and B. T. Forschler. 2002. DNA technology, interstate commerce, and the likely origin of Formosan subterranean termite (Isoptera: Rhinotermitidae) infestation in Atlanta, Georgia. J. Econ. Entomol 95: 381-389. PDF
Jenkins, T. M., R. Dean, R. Verkerk, and B. T. Forschler. 2001. Phylogenetic analyses of two mitochondrial genes and one nuclear intron region illuminate European subterranean termite (Isoptera: Rhinotermitidae) gene flow, taxonomy, and introduction dynamics. Mol. Phylogenet. Evol. 20: 286-293. PDF
Brickman, M .A., T.M. Jenkins, S. A. Clay, and N. H. Granholm. 2001. Genetic variation in Aphthona nigriscutis Foudras (Coleoptera: Chrysomelidae) populations introduced into the United States to biologically control leafy spurge. J. Entom. Sci. 36: 391-401.