The Distribution of Genetic Variation Among Relictual Populations of Missouri Tallgrass Prairie Plants
Date of Graduation
Fall 1994
Degree
Master of Science in Biology
Department
Biology
Committee Chair
John Heywood
Abstract
The amount of genetic variability that is lost from a species when an ecosystem is fragmented will be proportional to the magnitude of genetic differentiation among its individual populations. To assess the genetic effect of habitat destruction on tallgrass prairie plant species, Wright's F-statistics were used to describe the distribution of allozyme variation among five prairie preserves in Missouri for three plant species: Schizachyrium scoparius (little bluestem), which presumably reproduces in the prairie ecosystem predominantly via vegetative propagation, Ruellia humilis, which has a mixed mating system, and Liatris pycnostachya, which is an obligate outcrosser. The Fst estimates were 0.0318 for S. scoparius (two polymorphic loci), 0.0385 for R. humilis (six polymorphic loci), and 0.0242 for L. pycnostachya (seven polymorphic loci). thus, over 96% of the allozyme variation present within each of these species in Missouri is found with individual populations. The very low level of differentiation indicates that gene flow among prairie plant populations has been sufficient to counteract genetic drift in these populations, so that the present day system of prairie preserves should contain the majority of allozyme variability which was present in the unfragmented prairie ecosystem. This homogeneous pattern may not be present for genetic loci which are affected by selection.
Subject Categories
Biology
Copyright
© Cay Anne Carter
Recommended Citation
Carter, Cay Anne, "The Distribution of Genetic Variation Among Relictual Populations of Missouri Tallgrass Prairie Plants" (1994). MSU Graduate Theses. 100.
https://bearworks.missouristate.edu/theses/100
Dissertation/Thesis
