Our Team

The Whitehill Lab Christmas Tree Genetics team has many members, each of whom bring their own unique expertise and creativity to help reach the program's research goals.

Justin Whitehill, Ph.D.

Christmas Tree Genetics Program Lead
Dr. Whitehill received his PhD in Plant Pathology from The Ohio State University with a dissertation on ‘Mechanisms of resistance in ash against the emerald ash borer’. After completing his PhD, Dr. Whitehill joined the lab of Dr. Jörg Bohlmann – a pioneer in the field of forest genomics – at the University of British Columbia, Canada, where he developed and identified genomic resources and tools to advance efforts to rapidly detect insect resistance traits in the provincial spruce breeding programs. The Christmas Tree Genetics Program and the Whitehill lab at NC State University employs a range of genetic, breeding, genomic, molecular, biochemical, microscopic, ecological, entomological, and pathological techniques, designed to tackle the challenges facing Christmas tree production in North Carolina.

Angela Chiang

Research Associate / Laboratory Manager
Angela is the lab manager of the Christmas Tree Genetics Program and also works with the Forest Biotechnology Group. She helps with managing day-to-day activities in the lab, such as lab organization, ordering, and coordinating operations within the lab. She has a Bachelor of Science majoring in Biochemistry from the University of Victoria in Victoria, BC, Canada. She has over 10 years of lab experience working on the bench at the University of British Columbia. She is well-versed in molecular biology techniques and is experienced in cloning, transformation (bacteria, yeast, plant), protein expression and purification, DNA and RNA extraction, qPCR, terpene extraction, and GC-MS.

Shyam Kumar Barampuram, Ph.D.

Research Associate
Shyam has been a Research Associate with Christmas Tree Genetics group since August 2024.
He completed his Ph.D. in 2006 on an important medicinal tree Terminalia chebula, where he studied In vitro regeneration system and genetic transformation studies for first time. For the past twenty years, he has been actively working
in the research area of plant biotechnology with special focus on plant tissue culture, genetic
transformation and molecular biology research. He has worked as both a postdoctoral associate and a scientist in academia (NCSU and University of Missouri) and industry (BASF, Soils agro sciences), working on different plants species (turfgrass, medicinal plants) and row crops (corn, Soybean, Cotton, Canola, Sunflower and Rice). Now his mission is to develop an efficient somatic embryogenesis protocol in Pinus lambertiana (sugar pine) for a reforestation program and genetic transformation studies in sugar pine.

Robert Thomas

Research Associate
Robert’s work in the lab focuses on plant tissue culture and transformation. He earned his MS in Botany at NCSU in 1993. His career has revolved around row crops and commercial trees such as maize, sage, tobacco, Aspen, cottonwood, eucalyptus, pine, sweetgum and, currently, fir trees. The projects often aim to establish tissue cultures of elite genotypes. Once in culture, the tissue may be cloned for mass deployment, preserved in cryogenic storage, or genetically engineered for greenhouse & field trials to identify increased yields or pest resistance.

Amanda Saville

Research Associate
Amanda is the Christmas Tree Genetics Program’s disease diagnostician. She received her MS in Plant Biology from NCSU in 2010 and joined the CTG program in October 2025. Her research focuses on the population genetics of Phytophthora species, specifically those that cause Phytophthora root rot on Christmas trees, with aims to better understand their movement across space and time. She is also working on developing new molecular methods for identifying infection that will help deliver information to growers sooner.

Estefania (Stef) Elorriaga, Ph.D.

Postdoctoral Research Scholar
Stef has been a postdoctoral research scholar in the CTG program since January 2025. She is currently working on two omics-specific projects. First, she is assembling the first nuclear genome of the elongate hemlock scale (EHS), a challenging pest of true firs. This genome will serve as a critical resource for uncovering the genes governing pest-host interactions between EHS and its true fir hosts. Second, Stef is analyzing the transcriptomes of nearly fully dehiscent purple and yellow male catkins in Fraser fir, with the goal of identifying differentially expressed genes involved in anthocyanin biosynthesis. Genes discovered through this work will inform efforts to develop Fraser firs with purple or red needles. These catkin transcriptomes are also contributing to the structural and functional annotation of the Fraser fir genome. Looking ahead, Stef’s next project will investigate the genetic regulators controlling cone development in Fraser fir — a fundamental question with broad implications for Abies biology and the Christmas tree industry in western North Carolina.

James Duduit, Ph.D.

Postdoctoral Research Scholar
James is currently a Postdoctoral research scholar working with the Christmas Tree Genetics Program. His research is primarily focused on the identification and characterization of native transcriptional elements, namely promoters and terminators, for use in molecular breeding of Momi and Fraser fir. He is also developing a high-efficiency plant transformation protocol for Abies which will incorporate the native genetic elements with pathogen resistance and ornamental trait genes. This will allow for rapid breeding by introducing beneficial genetic sequences, overall increasing the speed of response to critical industry needs.

John Bagwell, Ph.D.

Postdoctoral Research Scholar
John is a Postdoctoral Research Scholar working as a breeding program manager for the Christmas Tree Genetics Program. His research involves contributing to the Fraser fir pedigree reconstruction project, field and lab tasks to help advance the next generation of Fraser fir breeding, and data analysis to help with these and other projects.

Sai Karthik

Ph.D. Student
Sai is a Doctoral student in the Department of Forestry and Environmental resources. He is from Warangal, India. He has a major in Entomology from UAS-Dharwad. His major research focus is studying insect-plant interactions through chemical ecology and molecular biology approaches. Sai joined the Christmas Tree Genetics lab in August, 2021. His prospective research at NC State includes unraveling the interactions of Fraser fir with elongate hemlock scale and balsam wooly adelgid.

Adarsha Devihalli

Ph.D. Student
Adarsha is a Research Assistant in the CTG program. His doctoral research focuses on studying the Phytophthora root rot disease in Fir Christmas trees. He completed his master’s in plant biotechnology from UAS, Bangalore. He was a Khorana scholar in 2018 and did his summer research internship at BTI, Cornell University. He is interested in understanding the plant-pathogen/pest interaction at molecular level. He loves questioning the ways of pathogenesis in plants and address these issues by adopting modern genomics/genetic tools.

Kaley Patton

Ph.D. Student
Kaley is a Ph.D. student in the CTG program. She double majored in Biology (Molecular, Cellular, and Developmental Biology) and Environmental Sciences during her undergraduate studies at NCSU. Her doctoral research focuses on terpenes in fir trees, specifically their potential role in deterring white-tailed deer browsing and shaping consumer perceptions of Christmas tree fragrance. She is investigating the biosynthesis of terpenes and their ecological and commercial importance using techniques such as RNA-seq, GC-MS, microscopy, and laser microdissection.

Jesse Hickman

Ph.D. Student
Jesse is a Ph.D. student in the CTG program. He graduated from Iowa State University
in 2023 with a degree in Agricultural Biochemistry. Initially trained in maize genetics, his
current research investigates drought tolerance traits in Fraser fir. Using several
physiological measurements in addition to monitoring environmental parameters, he
hopes to identify elite genotypes of Fraser fir that exhibit enhanced resilience to
abnormal growing conditions.

Ingrid Tuyuc Amezquita

Ph.D. Student
Ingrid is a Ph.D. student in the CTG Lab. She completed her M.S. at NC State as a Fulbright Scholar, and she is originally from Guatemala. Her doctoral research focuses on evaluating the genetic potential of exotic fir species (Abies spp.) used in the Christmas tree industry through the Collaborative Fir Germplasm Experiment (CoFirGE). She will collect data on traits that are important for Christmas tree production, including height growth, market quality, and resistance to Phytophthora root rot. She will also develop genomic tools, such as SNP-based genotyping panels, to reconstruct pedigrees and improve the accuracy of genetic selection for future Christmas tree breeding programs.

Haley Melton

Master’s Student
Haley is a Master’s student in the CTG program. She graduated with a Bachelor’s of Science in Botany from Miami University May of 2024. During undergrad she built upon an interest in plant-pest interactions while working in the university’s greenhouse and conservatory, where she gained experience managing greenhouse pests. She also worked for the City of Hamilton’s Urban Forestry Department, opening me to the world of pests in urban environments. Haley is excited to learn more with my research in Phytophthora root rot in Fraser fir in the CTG program. She is currently researching Phytophthora root rot in Fraser fir, specifically on the pathogenicity of different species of Phytophthora on Fraser fir and how environment stressors like drought may influence disease severity. She will also be assisting with phylogenetic studies of Phytophthora cinnamomi to better understand the relationships among isolates from across the U.S.

James Bulluck

Master’s Student
James is a master’s student in the Christmas Tree Genetics program. He graduated from NCSU in 2023 with a Bachelor’s of Science in Forest Management and joined the Christmas Tree Genetics lab Spring 2026. His master’s research is focused on the physiological response of poplar clones to Phytophthora infections, and screening American chestnut seedlings for Phytophthora resistance in collaboration with the American Chestnut Foundation.

Samantha Becerra Valdivieso

Undergraduate Research Assistant
Sam is a Senior majoring in Genetics at NC State University.

Anna Garner

Undergraduate Research Assistant
Anna is a Junior majoring in Biological Sciences and minoring in Biotechnology and Microbiology at NC State University. She joined the CTG lab in August of 2025. Since joining the lab, Anna has assisted with plant tissue culture, learned and performed molecular cloning protocols for terminator identification and exploration in Fraser fir, and has worked on design and updates for the A GIFT SEED and CTG Lab websites, respectively.

Ross Whetten

Professor Emeritus
Applications of molecular biology methods to solve practical problems in management of natural or planted populations of forest trees, with an emphasis on conifer species native to the southeastern USA. Massively-parallel or “next-generation” DNA sequencing technologies provide new opportunities to detect and analyze genetic variation in forest tree populations, and my research is focused on development and application of both new laboratory methods to generate data and new analytical methods to understand how genetic variation is related to variation in traits of ecological or economic importance.

John Frampton

Professor Emeritus
Christmas Tree Genetics and Breeding expert.
Christmas tree genetics, genetic conservation of Fraser fir; propagation and use of clones in forest tree species, host-pathogen interactions in forest diseases.