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Genetic Relationships, Morphological Divergence and Ecological Correlates in Three Species of the Viola canadensis Complex in Western North America
McCreary, Cheryl S.

2005, Doctor of Philosophy (PhD), Ohio University, Biological Sciences (Arts and Sciences).
Viola flettii, Viola cuneata and Viola ocellata are sister species within the Viola canadensis complex (Violaceae). All are endemics of western North America, growing in widely divergent ecological environments. During the summers of 1998, 1999, 2001 and 2002, leaf material for DNA extraction was collected from 26 populations of the three species, including much of their range. Analysis of V. flettii DNA using intersimple sequence repeat (ISSR) markers showed a great deal of diversity with percent polymorphic loci (P) of 65% and a disjunction between northern and southern populations. Statistical analysis of collected ecological data from V. flettii indicated a microhabitat effect of greater elevation and more southernly aspect leading to lowered genetic diversity and population size, respectively. Preserving the genetic diversity in V. flettii by protecting populations in both regions with emphasis on those at more optimal microhabitats will aid in maintaining the current fitness ability of this endemic species. Nested Clade Analysis (NCA) of Polymerase chain reaction - restriction fragment length polymorphisms (PCR-RFLP) data from chloroplast regions of all three species showed no distinct groupings based on taxon assignment, potentially indicating past hybridization and chloroplast capture during the early stages of speciation or subsequently and repeatedly within Pleistocene refugia harboring all three species. Contrary to the evidence suggesting hybridization and interspecific gene flow, ecological, environmental, leaf morphology and leaf angle data all show the three Viola species to be strongly distinct, supporting the idea that the three species are morphologically and ecologically well differentiated.
Harvey Ballard (Advisor)
209 p.

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McCreary, C. (2005). Genetic Relationships, Morphological Divergence and Ecological Correlates in Three Species of the Viola canadensis Complex in Western North America. (Electronic Thesis or Dissertation). Retrieved from https://etd.ohiolink.edu/

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McCreary, Cheryl. "Genetic Relationships, Morphological Divergence and Ecological Correlates in Three Species of the Viola canadensis Complex in Western North America." Electronic Thesis or Dissertation. Ohio University, 2005. OhioLINK Electronic Theses and Dissertations Center. 23 Oct 2018.

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McCreary, Cheryl "Genetic Relationships, Morphological Divergence and Ecological Correlates in Three Species of the Viola canadensis Complex in Western North America." Electronic Thesis or Dissertation. Ohio University, 2005. https://etd.ohiolink.edu/

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