Systematics and Geographic Relations of Phlox L. (Polemoniaceae)

Kansas State University, Manhattan KS

Investigators

Abstract

0089656 Ferguson and Patterson The North American genus Phlox (family Polemoniaceae), with about 64 species, has been the object of numerous ecological and evolutionary studies for many decades, but the taxonomy of the group has relied upon a now-50 year old monograph written before methods were available for clear, explicit analyses of phylogenetic relationships. Dr. Carolyn Ferguson at Kansas State University, with her colleague Dr. Robert Patterson at San Francisco State University, is studying molecular (DNA) and morphological patterns of variability in all the species of the genus, in order to construct a phylogenetic tree for the group, and thereby examine questions about evolution of pollination relationships, life history, geographic migration and ranges, and polyploidy and hybridization. Phlox is the largest genus in the family, and like all temperate genera in the family has its center of diversity in western North America. Efforts are underway to sample all of the species for molecular analyses of nuclear and chloroplast DNA sequences and for restriction-enzyme mapping of the chloroplast genome, as sources of mutational characters for phylogenetic analysis. Field and herbarium studies will also add new data from morphology, and for re-examination of published descriptions. Hybridization has been reported in a number of species complexes in Phlox, and has been confirmed in the pilosa and glaberrima groups, and will be the focus of combined nuclear and chloroplast analyses. The combined molecular and morphological studies of the genus will facilitate writing of major taxonomic treatments for the species for the ongoing Flora of North America project, as an additional contribution.