Our Scientists

Dr. Lisa Alexander

Research Geneticist
{McMinnville, TN}
Lisa.Alexander@usda.gov

Conducts research to develop, evaluate, and release improved germplasm of selected nursery crop species, including, but not limited to, Hydrangea, Osmanthus, and Callicarpa, and utilize genetic markers to accelerate the breeding process. Click here for more details

Mr. Kevin Conrad

Botanist
{Beltsville, MD}
Kevin.Conrad@usda.gov

Responsible for the conservation of 182 genera (over 5000 taxa) of woody landscape plants of diverse wild-origin; to establish a viable repository (Woody Landscape Plant Germplasm Repository - WLPGR) for the long term preservation of this germplasm in the form of seeds and clonal material; to transfer technology and associated information for use in research and crop improvement; and, to establish, manage, and make available collections information by electronic links between U.S. National Arboretum, National Plant Germplasm System, and the public sector. Click here for more details

Dr. Fred Gouker

Research Geneticist
{Beltsville, MD}
Fred.Gouker@usda.gov

Conducts research on breeding and genetic improvement of woody ornamental landscape trees and shrubs including boxwood, catalpa, hemlocks, and additional underutilized germplasm for developing new selections or cultivars with improved tolerances to stress, diseases, and pests for the nursery and landscape industries and for the public. Methodologies used for carrying out research include traditional breeding, molecular markers, and advanced genetic and genomic technologies.

Dr. John Hammond

Research Plant Pathologist
{Beltsville, MD}
John.Hammond@usda.gov

Conducts research on virus diseases of ornamental crops, including identification and characterization of newly occurring viruses, resistance to virus infection and replication in transgenic plants, and virus detection and strain differentiation by serology and nucleic acid hybridization. Development of a Universal Plant Virus Microarray for detection and identification of plant viruses. Click here for more details

Dr. Qi Huang

Research Plant Pathologist
{Beltsville, MD}
Qi.Huang@usda.gov

Identifies, detects, and gains a better understanding of genetic relationships and molecular basis of pathogenicity of selected bacterial pathogens to facilitate effective control of bacterial diseases of major significance to ornamental and agronomic crops. Current research interests include: conducting research on Xylella fastidiosa including genome characterization and specific detection and identification of ornamental strains, as well as genetic relationships among ornamental and non-ornamental strains of X. fastidiosa; and improving current detection and identification methods for the select agent pathogen Ralstonia solanacearum race 3 biovar 2. Click here for more details

Dr. Ramon Jordan

Research Plant Pathologist
{Beltsville, MD}
Ramon.Jordan@usda.gov

Conducts research on the biochemical and biological nature of plant viruses, their genomes, and their gene products. Develops and utilizes serological and nucleic acid-based reagents and technologies for improved detection, differentiation and identification of new and emerging viruses; determines the genome organization of selected important ornamental viruses; and, develops methods and new strategies to confer virus resistance in plants through expression of antibody proteins or replicase-binding peptides in transgenic plants. Click here for more details

Dr. Margaret Pooler

Research Leader
{Beltsville, MD}
Margaret.Pooler@usda.gov

Conducts basic and applied research on breeding and genetics of ornamental shrubs and small trees, including flowering cherries, redbuds, and crapemyrtles, in order to develop new cultivars that are disease and pest resistant, tolerant of environmental stresses, and have superior ornamental qualities. Breeding methodologies include traditional crosses, ploidy manipulation, in-vitro techniques, as well as using molecular markers to identify hybrids or assess genetic diversity. Click here for more details

Dr. Todd Rousaville

Horticulturist
{Beltsville, MD}
Todd.Rounsaville@usda.gov

Leads the U.S. National Arboretum Germplasm Program to improve the genetic and taxonomic resource base of woody plants in cultivation. Conducts research on genetic diversity, seed biology, and germplasm management via regeneration, storage, and gap analysis. Leads and collaborates on expeditions for domestic and international plant collection, germplasm evaluation trials, and plant conservation efforts both in situ and ex situ.

Dr. Scott Warnke

Research Geneticist
{Beltsville, MD}
Scott.Warnke@usda.gov

Conducts research on the genetics of plants used as turfgrasses. Identifies and develops enhanced germplasm from wild species that express improved biotic and abiotic stress resistance. Develops improved turfgrasses through the use of new technologies such as molecular markers and genomics. Click here for more details

Dr. Alan Whittemore

Research Botanist
{Washington, DC}
Alan.Whittemore@usda.gov

Responsible for original molecular, biosystematic, taxonomic, and nomenclatural research on cultivated woody plants and their wild-occurring allies of potential scientific, economic, and landscape utility. Leads and joins domestic and foreign plant explorations. Responsible for, provides oversight of, and contributes actively to the growth and proper curation of the U.S. National Arboretum Herbarium. Click here for more details