Identifies the potential insect vectors of the bacterium that causes
bacterial leaf scorch and decline of landscape trees such as red oak and American elm. Tests the genetic resistance among maple clonal
selections against the potato leafhopper by identification of readily screenable genetic traits that will enable selection of more insect-resistant
red maples. Tests the effect of shading on the nutritional suitability and moisture content of azalea as a host to the azalea lace bug as a possible
strategy for controlling this insect and improving efficacy of natural enemies.
Click here for more details e-mail: BentzJ@ba.ars.usda.gov
Dr. Donna Fare
Research Horticulturist
{McMinnville,TN}
Conducts a research
program associated with nursery crop production with emphasis on: developing
improved propagation methods and production protocols for hard-to-propagate
nursery plants, as well as addressing problems associated with field and
container production quality nursery plants, including development of environmentally
sound cultural practice guidelines. Click here for more details e-mail: dfare@blomand.net
Dr. Robert J. Griesbach
Research Geneticist
{Beltsville, MD}
Conducts a broad based
research program in the genetics of floral plants. Enhanced germplasm is created
from wild species that is disease, insect and stress tolerant. New technologies
(i.e., embryo rescue, genetic engineering, molecular markers, etc.) are developed
to aid in creating of novel germplasm. Recent research focuses on determining the
inheritance of horticulturally valuable traits, such as flower color. The genetics
of anthocyanin gene regulation is being studied. Click
here for more details e-mail: GriesbaR@ba.ars.usda.gov
Dr. John Hammond
Supervisory Research Plant
Pathologist, Research Leader {Beltsville,
MD}
Conducts research
on virus diseases of ornamental crops, including resistance to virus infection
and replication in transgenic plants, and virus detection and strain differentiation
by serology and nucleic acid hybridization.
Click
here for more details
Develops methods
of eliciting specific immune response for production of polyclonal antisera
and monoclonal antibodies and develops sensitive techniques for rapid and
reliable identification of plant pathogens. Conducts research on virus-vector-host
plant interaction. Investigates vector cell culture system for studies
of plant viruses. Click here for more details e-mail: HsuH@ba.ars.usda.gov
Dr. Qi Huang
Plant Pathologist
{Beltsville, MD}
Conducts research on important bacterial diseases of floral and woody
crops. Current research interests include: developing knowledge and tools for the detection, genetic characterization and control
of bacterial leaf scorch disease of woody ornamental crops caused by Xylella fastidiosa; conducting research on epidemiology and
control of bacterial wilt disease of geranium caused by Ralstonia solanacaerum; and identifying alternative plant expression
promoter and developing transgenic floral crops for bacterial resistance.
e-mail: HuangQ@ba.ars.usda.gov
Dr. Ramon L. Jordan
Research Plant Pathologist
{Beltsville, MD}
Conducts research on the biochemical, biological,
and immunological nature of plant viruses, their genomes and gene products.
Develops monoclonal and single-chain antibodies to study antigenic structures and, in addition
to nucleic acid-related techniques, for improved viral detection and identification.
Develops methods to confer virus resistance through expression of antibody
proteins or replicase-binding peptides in transgenic plants. Click here for more details
Identifies biochemical
events associated with cell division and differentiation. Studies cell,
tissue and organ development and correlates biochemical changes with morphological
changes leading to formation of the whole plant. Applies information to
creating transgenic plants. Click
here for more details e-mail: KamoK@ba.ars.usda.gov
Dr. Margaret Pooler
Research Geneticist
{Washington, DC}
Conducts research
on breeding and genetics of ornamental shrubs, small trees and woody perennials.
Breeding methodologies include traditional crosses and plant transformation
to introduce novel genes for disease resistance, environmental adaptation,
and esthetic qualities, as well as using molecular markers to facilitate
selection. Click
here for more details
Conducts research
on breeding and genetics of nursery crop species (for example, dogwoods, and
hydrangea) to develop improved cultivars, with particular emphasis
on resistance to diseases and insects and tolerance to environmental stress.
Uses both traditional breeding methodology and in vitro techniques. Leads
inter-disciplinary evaluation of woody ornamental cultivars and breeding lines.
Click
here for more details e-mail: SReed@blomand.net
Dr. Mark S. Roh
Research Horticulturist
{Beltsville, MD}
Conducts research on germplasm as part
of the woody landscape plants repository project (WLPGR).
Specific research objectives include, for example: evaluating seed germination of Styrax
as investigated by nuclear magnetic resonance imaging, determining overwinter loss of vegetatively
propagated propagules of Styrax, evaluating germplasm for heat tolerance in Abies, Pinus,
Deutzia, Halesia as well as other ornamental plants with horticultural merit, and
characterization of germplasm such as Ilex, Corylopsis, and Camellia using,
for example, molecular markers.
Click here for more details e-mail: RohM@ba.ars.usda.gov
Dr. Alden M. Townsend
Research Geneticist
{Glenn Dale, MD}
Responsible for research
on genetic improvement of elms, maples, hemlocks, hackberries, alders, and tupelos.
The emphasis is on increasing disease- and insect-resistance in these groups of urban
trees. Released the first two American elm cultivars ('Valley Forge' and 'New Harmony')
tolerant to Dutch elm disease (DED) to nurserymen and the American public. We are
working on identifying a greater diversity of clones of American elms for disease
tolerance, in order to prevent the planting of monocultures, which might prove
susceptible in a new DED epidemic. Have also released new insect-tolerant red
maple cultivars, 'Brandywine', 'Somerset', 'Sun Valley', 'New World', and 'Red Rocket'.
The first three of these are available commercially. New hybrids between different
species of hemlocks have been created and verified by DNA fingerprinting; these hybrids
will be outplanted for long term evaluation of resistance to the hemlock woolly adelgid.
Click here for more details e-mail:
nadt@sun.ars-grin.gov
Dr. Scott Warnke
Research Plant Geneticist/Physiologist
{Washington, DC}
Conducts research on
germplasm evaluation, plant genetics, plant physiology and germplasm enhancement
of turfgrasses. Research is focused on an improved understanding of genetic
processes underlying stress responses of turfgrasses, which will also
lead to improved techniques for plant selection and breeding through the use of molecular
marker techniques in germplasm enhancement.
e-mail: WarnkeS@ars.usda.gov
Dr. Alan Whittemore
Research Plant
Molecular Taxonomist
{Washington, DC}
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 National
Arboretum Herbarium.
e-mail: WhittemA@ars.usda.gov
Dr. Jo-Ann Bentz
e-mail: BentzJ@ba.ars.usda.gov
Dr. Donna Fare
Dr. Robert J. Griesbach
Dr. Hei-Ti Hsu
Dr. Qi Huang
Dr. Ramon L. Jordan
Dr. Kathryn K. Kamo
Dr. Sandra Reed
Dr. Mark S. Roh
Dr. Alden M. Townsend
Dr. Scott Warnke
Dr. Alan Whittemore
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