| As a result of urbanization and agricultural development, the tallgrass prairie is one of the most endangered ecosystems in North America. In Ohio, prairies are small, isolated, and susceptible to environmental and genetic stresses. The research conducted for this dissertation focuses on two main aspects of the Ohio tallgrass prairie ecosystem: (1) the genetic diversity and relatedness of the prairie remnants located to Ohio and how they compare with prairie remnants in more western states; (2) the association with arbuscular mycorrhizal (AM) fungi. Because of its widespread occurrence in the tallgrass prairies, big bluestem (Andropogon gerardii ) was used as a model plant.; Results from RAPD (Randomly Amplified Polymorphic DNA) analysis revealed that individuals of big bluestem have maintained high levels of genetic diversity in all populations. Statistical analysis showed a general clustering of the more eastern populations, while populations in KS and MO were more distinctly separated. Within Ohio, populations were generally more genetically similar to each than to prairie regions sampled further west. There is a possibility that populations on the geographic edge of the Prairie Peninsula are specifically adapted to their local environment. Management and revegetation efforts should therefore take caution with the introduction of propagules from geographically distant regions.; A total of five arbuscular mycorrhizal (AM) species associated with big bluestem were identified from nine prairie remnants in Ohio. AM inoculum studies revealed a significant degree of variability in big bluestem growth relative to plant origin, mycorrhizal treatment, as well as soil type. Although mycorrhizal infection did not always benefit plant growth, big bluestem generally showed a positive growth response to mycorrhizal colonization. While the incorporation of an AM inoculum to prairie reintroduction projects may be appropriate and may greatly enhance its success, plant genotype, inoculum type, and the soil environment should first be considered. |
