Research Grants Awarded in 2008
The Research Committee recommended that the Research Foundation of the American Rhododendron Society provide
funding for the following four proposals in 2008:
#08-1. Nonanoic Acid and Trichoderma Isolates for Management of Botrytus Petal Blight and
Phytophthora Dieback. Thomas J. Gianfagna, Department of Plant Biology and Pathology, Rutgers University,
New Brunswick, NJ - $5,000.
Summary of Proposal
It has been discovered that some microorganisms have antibiotic control of fungal pathogens. The
research involves isolation of specific compounds from specific kinds of bacteria and testing
their effect on two kinds of fungal disease under controlled greenhouse conditions. The anticipated
benefits to rhododendron growers are a potential biofungicide that will be cheaper than currently registered
conventional fungicides and which is environmentally friendly.
#08-2. Identification and Classification of Rhododendron Powdery Mildew in the Pacific Northwest,
Dean A. Glawe, College of Forest Resources, University of Washington, Seattle, WA - $5,000.
Summary of Proposal
Powdery mildew is a serious disease of susceptible rhododendron cultivars and species causing leaf spotting,
defoliation, and reduced growth. This is more of a problem in different regions of the country, but particularly
in the Pacific Northwest. The taxonomy of powdery mildew is very complex involving many different species. This
project will characterize the morphology of powdery mildew fungi on Rhododendron species using light and
scanning electron microscopy and will assess relationships among these fungi using nucleic acid sequences.
The objective is to use this classification information to determine the correc names of the North American powdery
mildews on Rhododendron species. This research will enable plant pathologists and rhododendron breeders to target
more effectively their efforts in controlling powdery mildew.
#08-3. Genome Sizes in Rhododendron ssp., Leen Leus, Institute of Agricultural and Fisheries Research,
Melle, Belgium - $3,114.
Summary of Proposal
The numbers of chromosomes, also known as ploidy levels, are of interest for plant breeders as polyploidy (extra
sets of chromosomes) can influence characteristics of growth vigor or in the case of ornamentals, the ornamental value.
The analysis of the DNA content can give more information than just the ploidy level. Although a lot of information is
available about the number of chromosomes among certain genotypes of rhododendrons, little information is available
about the genome size. Genome size is important from a phylogenetic point of view and also important for plant
breeding.
#08-4. Are There Toxins in Rhododendron Nectar? Geraldine A. Wright, Newcastle University, Newcastle upon
Tyre, United Kingdom - $4,300.
Summary of Proposal
The plant tissues of rhododendrons are know to contain toxins that affect nerve and muscle cells when ingested by animals.
There are also accounts of "mad honey" consumed by humans reported back to ancient history. The question arises as to
why rhododendrons have toxin in the nectar they offer to pollinators. The research will try to determine how widespread toxins
are throughout a large number of different Rhododendron species. This proposal describes nectar as the "currency" between
pollinators and plants and it is the nectar that attracts many insects. The objective of this research is to determine whether
the presence of rhododendron-specific toxins (grayanotoxins) in nectar correlates with pollinator type predicted on the basis
of rhododendron floral traits.