Collaborative Research: Population differentiation in an herbaceous plant: genetic divergence and outbreeding depression

George Washington University, Washington DC

Investigators

Abstract

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). ABSTRACT In plants, the distinction between species is often not complete, allowing for the production of hybrids that frequently perform poorly. Conversely, within a single species, genetic differentiation may develop between isolated populations resulting in poor performance of crosses, termed outbreeding depression. The long-term goal of this research is to evaluate patterns of outbreeding depression and genetic divergence for an herbaceous plant where preliminary data reveal up to a 90% reduction in performance of between-population crosses relative to their parents. Addressing this goal requires molecular genetic markers suitable for assessing population differentiation. The proposed research will develop molecular markers and use those markers to evaluate divergence among four isolated populations. Studies of genetic divergence and outbreeding depression are important as they provide a glimpse into the earliest stages of speciation. In addition, conservation and restoration programs often involve combining individuals from different populations. A greater understanding of the source of outbreeding depression is necessary to make management decisions about mixing gene pools from different populations.