Ken Keefover-Ring Ph.D.
Post-doctoral Research Associate

Laboratory of Chemical Ecology
Dr. Richard Lindroth

Department of Entomology
University of Wisconsin
Madison, WI 53706
keefover@entomology.wisc.edu

Curriculum Vitae

Research:

I study chemical ecology. Chemical ecologists examine plant secondary compounds and how these chemicals mediate interactions with other community members coexisting with plants. Secondary compounds include such chemicals as essential oils (monoterpenes) and alkaloids (caffeine and nicotine). These chemicals were originally thought of as “secondary” because they are not necessary for plant primary metabolism, like proteins, DNA, or sugars. However, later we realized that plants use secondary chemicals for a variety of important functions, including deterring herbivores, attracting pollinators, and even inhibiting competition by other plants (allelopathy).

For may masters I studied terpenoid chemistry and herbivores in the seed cones of ponderosa pine. This specialized group of insects lays eggs in or on green second-year cones and the larvae mine the cone's interior, destroying seeds and effecting plant fitness.

My PhD focued on essential oil polymorphisms of plant species in the Lamiaceae (Mint) family. Due to these polymorphisms, different individuals within a species produce distinct essential oils, also called monoterpenes. The monoterpenes from various chemical phenotypes (chemotypes) have differential effects on organisms such as pollinators, herbivores, and other plants. I use two primary study organisms, a Mediterranean native Thymus vulgaris or common thyme, and Monarda fistulosa, a North American species also known as bee balm or wild bergamot.

Currently I am studying the effects of artificial browsing, similar to that of a large herbivore, and different nutrient levels on young aspen (Populus tremuloides). This works involves growing replicates of several different aspen genotypes, all originally collected form southern Wisconsin, in large pots in a common garden setting on the University of Wisconsin campus under a low and high nutrient treatment and removing 50-75% of the above ground biomass on half of the trees. The different genotypes are then monitored for any changes in secondary chemistry (phenolic glycosides and condensed tannins), ability to regrow after browsing, which includes leaf area and mass and branching patterns.

Pine cones and insects  |  Wild Bergamot

Thyme  |  Aspen

Peer Reviewed Publications:

K. Keefover-Ring and Y. B. Linhart. In press. Variable chemistry and herbivory in ponderosa pine cones. International Journal of Plant Sciences

K. Keefover-Ring, Thompson, J. D., and Y. B. Linhart. 2009. Beyond six scents: defining a seventh Thymus vulgaris chemotype new to southern France by ethanol extraction. Flavour and Fragrance Journal 24: 117-122

Groendahl, E., B. K. Ehlers, and K. Keefover-Ring. 2008. New cis-sabinene hydrate chemotype detected in large thyme (Thymus pulegioides L.) growing wild in Denmark. Journal of Essential Oil Research 20: 40-41

Thompson, J. D., P. Gauthier, J. Amiot, B. K. Ehlers, C. Collin, J. Fossat, V. Barrios, F. Arnaud-Miramont, K. Keefover-Ring, and Y. B. Linhart. 2007. Ongoing adaptation to Mediterranean climate extremes in a chemically polymorphic plant. Ecological Monographs 77(3): 421-439

Linhart, Y. B., K. Keefover-Ring, K. A. Mooney, B. Breland, and J. D. Thompson. 2005. A chemical polymorphism in a multi-trophic setting: thyme monoterpene composition and food web structure. American Naturalist 166(4): 517-529

Dissertation:

K. Keefover-Ring. 2008. One Chemistry, Two Continents: Function and Maintenance of Chemical Polymorphism in the Mint Family (Lamiaceae).

Non-peer Reviewed Publications:

K. Keefover-Ring. 2007. Prairies make good scents: Bee balm, a prairie native. The Shortgrass Prairie Review 3(3): 8-9  

K. Keefover-Ring. 2006. Monarda fistulosa: Making good scents in Colorado. Aquilegia 30(2): 3-4