Abstract Detail

Systematics Section/ASPT

Eserman, Lauren [1], Tiley, George [2], Jarret, Robert L. [3], Leebens-Mack, Jim [1], Miller, Rick [4].

Phylogenetics and diversification of morning glories (Ipomoeeae, Convolvulaceae) based on whole plastome sequence data.

Morning glories (Convolvulaceae) are a diverse angiosperm group within which higher-level relationships are not well understood. Phylogenetic studies have demonstrated the largest morning glory genus, Ipomoea, is not monophyletic. Rather, nine other genera are nested within Ipomoea. Therefore, systematic research is focused on the monophyletic tribe Ipomoeeae (c. 900 species). The present study uses whole chloroplast genome sequence data to resolve deeper relationships across a broad sample of Ipomoeeae species. Whole plastomes were sequenced, assembled and annotated for twenty-eight morning glory species, representing the major Ipomoeeae lineages. Phylogenies were estimated for the twenty-eight species sequenced here and one published plastome using eighty-two protein-coding and rRNA chloroplast genes and a whole plastome alignment. In addition, divergence times were estimated for major clades across the Ipomoeeae. Fossil pollen data for two nodes were used to calibrate the molecular dating analyses. Phylogenies estimated from whole plastome and concatenated gene alignments had identical topologies, which were generally consistent with prior phylogenetic analyses of morning glories. Two major clades, previously named the Astripomoeinae and Argyreiinae, were well-supported. There also was significant support for the monophyly of Ipomoea subgenus Quamoclit. Higher-level relationships with weak support in previous phylogenies were recovered in this analysis with strong support. Results from the molecular dating analysis suggest a middle Eocene divergence time for the Ipomoeeae. Furthermore, the Argyreiinae clade was found to have diversified before the Astripomoeinae clade; however, error bars overlap between divergence time estimates for these two clades. Phylogenetic results presented here provide greater confidence in the relationships among major lineages of the Ipomoeeae, and divergence time estimation results provide an approximate temporal context for the diversification of this fascinating group of angiosperms.

Broader Impacts:

1 - University of Georgia, Plant Biology Department, Athens, GA, 30602, USA
2 - University of Florida, Department of Biology, Gainesville, FL, 32611, USA
3 - US Department of Agriculture, Plant Genetics Resources Conservation Unit, Griffin, GA, 30223, USA
4 - Southeastern Louisiana University, Department of Biological Sciences, Hammond, LA, 70402, USA

Keywords:
morning glories
Ipomoeeae
Convolvulaceae
Phylogenetics
plastid sequences.

Presentation Type: Oral Paper:Papers for Sections
Session: 13
Location: Rosedown/Riverside Hilton
Date: Monday, July 29th, 2013
Time: 2:00 PM
Number: 13003
Abstract ID:576
Candidate for Awards:George R. Cooley Award