Life Sciences Commons^™

Patterns Of Genetic Divergence Across Geographically Variable Populations Of Xanthisma Gracile (Asteraceae), Lavanya Challagundla, Lisa E. Wallace

Biological Sciences Faculty Publications

Premise of research. Numerous biotic and abiotic factors can contribute to local selection and lead to geographic structure and genetic divergence between populations. The southwestern United States contains many distinctive plant communities, ranging from woodlands to desert scrub, that are shaped by species adapting to local variation in elevation, precipitation, seasonality, and soils. Given this variation, species occurring across diverse habitats are expected to harbor high genetic diversity and exhibit significant genetic differences associated with environmental variation.

Methodology. Here, we studied the genetic divergence of populations of Xanthisma gracile (Asteraceae) across Arizona using amplified fragment length polymorphisms and evaluated associations …

Patterns Of Genetic Diversity In Highly Invasive Species: Cogongrass (Imperata Cylindrica) Expansion In The Invaded Range Of The Southern United States (Us), Rima D. Lucardi, Lisa E. Wallace, Gary N. Ervin

Biological Sciences Faculty Publications

The spatial expansions of invasive organisms in the novel range are generally expected to follow an isolation-by-distance relationship (IBD) if the invasion is biologically driven; however, many invasions are facilitated anthropogenically. This research focused on the extant expansion patterns of cogongrass (Imperata cylindrica). Cogongrass is a widespread invasive species throughout the southern United States (US). Patterns of infestation vary among US states. Cogongrass is pyrogenic, and its invasion threatens softwood (Pinus spp.) plantations, a substantial economic market for this US region. Over 600 individuals were sampled from seven invaded US states, using amplified fragment length polymorphisms (AFLPs) …