Merrill, Keith , Meyer, Susan E. , Coleman, Craig .
Genetic Diversity and Population Structure Among Bromus Tectorum Populations in Intermountain Western North America as Determined by Microsatellite Analysis.
Bromus tectorum L. (cheatgrass or downy brome) is an inbreeding annual weed introduced into the United States in the mid-to-late nineteenth century. Invasion throughout the Intermountain West has been characterized by multiple introductions followed by rapid expansion. We seek to better understand the connections between B.tectorum genotypes and the habitats in which they are found, as well as to discover why this species is such a successful invader. We report on genetic diversity and population structure for 98 populations of B. tectorum from throughout the Intermountain West, as determined through microsatellite (SSR) analysis. Preliminary analyses indicate a high level of structure among populations and much greater genetic variation than was previously revealed for this species in studies using allozyme analysis. Populations in harsh, xeric valley habitats tend to be dominated by single microsatellite genotypes that are rare or absent at upland sites, whereas populations from more mesic upland environments are often more genetically diverse. We discuss the implications of these data, the limitations underlying our current microsatellite markers, and the potential for developing a more robust marker system for use in more detailed genetic analysis.
Log in to add this item to your schedule
1 - Brigham Young University, Plant and Wildlife Sciences, 287 Widtsoe Building, Provo, Utah, 84602 , United States
2 - USDA Forest Service, Rocky Mountain Research Station, Shrub Sciences Laboratory, 735 N 500 E, Provo, Utah, 84606, USA
Presentation Type: Oral Paper:Papers for BSA Sections
Location: Cottonwood C/Snowbird Center
Date: Monday, July 27th, 2009
Time: 10:30 AM