Master of Science (MS), Ohio University, 2003, Environmental Studies (Arts and Sciences)

The purpose of this thesis was to investigate pollen-mediated gene flow and genetic variation within populations of Manfreda virginica that occur in prairie openings in Adams County, Ohio. M. virginica was chosen because of its historic co-dominance in the xeric prairies and its role as a dominant plant in globally rare limestone seep habitats. A pollen surrogate was used to estimate pollen dispersal and inferred pollen movement is frequent within populations, but not among populations. A single species of Halictid bee appears to be the primary and perhaps sole pollinator. Genetic analysis was performed using Inter-Simple Sequence Repeat (ISSR) markers. No significant relationship was found between geographic distance and genetic distance and substantial genetic variation is found between all populations regardless of size or geographic position. Heterozygosity and polymorphism was low within all populations. Analysis indicates substantial fixation of alleles within populations, perhaps driven by drift due to genetic isolation.

Committee: Harvey Ballard (Advisor) Subjects: Biology, Botany