Create your own conference schedule! Click here for full instructions

The Virtual Conference is located at

Abstract Detail


Moore, Erika [1], Mandel, Jennifer [2].

Reconstructing evolutionary relationships in the genus Packera (Asteraceae: Senecioneae).

The largest tribe in Asteraceae, Senecioneae, is comprised of about 150 genera and 3,500 species. Within Senecioneae, the genus Packera (subtribe Senecioninae), has roughly 88 species and varieties that are endemic to North America. Packera was previously included in the genus Senecio as the informal group known as “aureoid senecios” by Asa Gray. They were then distinguished as the new genus Packera in 1976 by Á. Löve & D. Löve based on having different base chromosome numbers (x=22,23), various morphological differences, and molecular phylogenetic data. Species boundaries in Packera are imprecise and taxonomy within Packera remains complex due to the species’ ability to easily hybridize, and because polyploidy is common throughout the genus, with roughly 40% of taxa being polyploids. The goal of this study is to reconstruct evolutionary relationships in Packera by generating a robust nuclear and plastid phylogeny, as well as estimating its age. By doing so, I hope to address 1) is Packera, as currently circumscribed, monophyletic, 2) how are Packera species related, and which species are the earliest diverging lineages in the phylogeny, and 3) how do the species relationships reconstructed via the plastid and nuclear data compare? To address these questions, I plan to employ targeted sequence enrichment methods combined with next generation sequencing (NGS) on a nearly complete sampling of the genus. Thus far, 78 out of the 88 species of Packera, as well as 17 outgroup species, have been sequenced and used to generate preliminary phylogenies. I used two phylogenomic workflows, HybPiper and PHYLUCE , that each apply different approaches for orthology assignment. Preliminary results have shown that PHYLUCE, which applies a conservative approach to assigning orthology, removes many potentially paralogous sequences resulting in large amounts of missing data. The HybPiper pipeline retains one sequence among potentially paralogous sequences, based upon criteria set by the user, and results in substantially lower levels of missing data. Gaining a better understanding of Packera’s evolutionary history and relationships can aid in our understanding of how traits such as hybridization or polyploidy play a role in speciation events within complicated taxa.

Log in to add this item to your schedule

1 - University Of Memphis, Biological Sciences, 3744 Walker Ave, 239 Ellington Hall, Memphis, TN, 38152, United States
2 - University Of Memphis, Biological Sciences, 3744 Walker Ave, 339 Ellington Hall, Memphis, TN, 38152, United States


Presentation Type: Poster
Session: P3, Phylogenomics Posters
Location: Virtual/Virtual
Date: Wednesday, July 21st, 2021
Time: 5:00 PM(EDT)
Number: P3PL004
Abstract ID:281
Candidate for Awards:None

Copyright © 2000-2021, Botanical Society of America. All rights reserved