Genetic Structure And Demography Of Chloropyron palmatum, An Endangered Annual Plant

Abstract Chloropyron palmatum (Ferris) Tank & J.M Egger (formerly Cordylanthus palmatus [Ferris] J. F. Macbr.) is an annual plant that inhabits seasonally flooded wetlands with saline and alkaline soils in California. In 1986, the plant was listed as endangered under the U.S. Endangered Species Act. We aimed to inform conservation strategies for the species’ five remaining populations by examining the genetic diversity and structure of the populations (on the basis of nuclear DNA markers) and their potential response to demographic and environmental stochasticity. We also assessed fluctuations in population size and whether there was evidence of hybridization between C. palmatum and Chloropyron molle (A. Gray) A. Heller subsp. hispidum (Pennell) Tank & J.M. Egger (formerly Cordylanthus mollis A. Gray subsp. hispidus [Pennell] T.I. Chuang & Heckard). Populations of C. palmatum were genetically distinct with a FST of 0.23, indicating substantial genetic structure among populations. Within populations, there...