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titleboxMICHELE R. DUDASH titlebox

professor pictureAssociate Professor, Director of BEES Program

email:mdudash@umd.edu
phone:
301.405.1642 (office)
fax:301.314.9358
office:3202 Bio-Psych
graduate programs: Biology, BEES
bullet visit lab page   bullet most recent publications


RESEARCH INTERESTS

My research interests are motivated by my curiosity of what factors contribute to plant population's persistence or demise over time. The research in my lab encompasses the evolution and maintenance of breeding systems, plant-pollinator interactions, and the demography of populations. In this framework, the basic research conducted in my lab has direct implications for conservation and restoration strategies of threatened and endangered species. I am interested in sponsoring graduate students in all aspects of plant population biology. The questions addressed in my research program often require field experiments, complimented by greenhouse and laboratory studies.

I am particularly interested in quantifying the selective forces responsible for the evolution and/or maintenance of a specific breeding system by a taxon. Many plants, unlike most animals, reproduce by both self-fertilization and outcrossing to other individuals in the local population. Plants have evolved numerous mechanisms to promote matings between individuals and inhibit self-fertilization. This is because many plants experience inbreeding depression following self-fertilization at one or more stages in their life cycle, that reduces overall fitness compared to an individual that results from a mating between two unrelated individuals.

I have documented the magnitude and the genetic basis of inbreeding depression in two rapid cycling, closely related Mimulus species. One species is primarily an outcrosser and the other is primarily a selfing species. Inbreeding depression may be due to partially deleterious recessive alleles and/or overdominance where heterozygotes are superior to either homozygote. A priori, theory predicts that the magnitude of inbreeding depression will be less in a selfing species compared to an outcrossing species because partially deleterious recessive alleles are more readily purged from a selfing population. We examined the genetic basis of inbreeding depression via two approaches; (1) a quantitative genetics breeding design for both taxa and (2) sequential generations of selfing and outcrossing in the outcrossing taxon to examine the extent of purging in the populations. Future research stemming from this project is to understand the genetic basis of the great variation among maternal lines in their expression of inbreeding depression and how they respond to different inbreeding regimes across varying environments.

I am also involved in a long-term collaborative project to investigate the role of the ruby-throated hummingbird in the evolution of floral morphology and flowering time in the wide-spread, North American endemic, red flowered Silene virginica. We are using a multi-faceted approach that incorporates yearly demographic monitoring, floral and whole plant manipulations, and reproductive enhancement treatments in this study. This research takes me each year to University of Virginia's field station, Mountain Lake Biological Station in Pembroke, VA.

Recent Publications


Fenster, C. B., G. Cheely, M. R. Dudash and R. J. Reynolds. 2006. Nectar Reward and Advertisement in Hummingbird-Pollinated Silene virginica, (Caryophyllaceae). American Journal of Botany 93: 1800-1807.

Murren, C. J., L. Douglass, A. Gibson, and M. R. Dudash. 2006. Individual and combined effects of serpentine and drought on trait expression in Mimulus guttatus. Ecology 87: 2591-2602.

Kephart, S. R. J. Reynolds, M. Rutter, C. B. Fenster, and M. R. Dudash. 2006. Pollination and seed predation by moths on Silene and allied Caryophyllaceae: Evaluating a model system to study the evolution of mutualisms. New Phytologist 169: 667-680.

Dudash. M. R., C. J. Murren, and D. E. Carr. 2005. Using Mimulus as a model system tounderstand the role of inbreeding in conservation and ecological approaches. Annals of the Missouri Botanic Garden. 92(1): 36-51.

Knight, T. Tiffany M. Knight, J. A. Steets, J. C. Vamosi, S. J. Mazer, M. Burd, D. R. Campbell, M. R. Dudash, M. O. Johnston, R. J. Mitchell, and T-L. Ashman. 2005. Pollen Limitation of Plant Reproduction: Pattern and Process. Annual Review of Ecology, Evolution, and Systematics 36: 467-497.