Abstract Detail

Revolutionizing systematics: Herbaria in the Genomics Age

McAllister, Chrissy [1], McKain, Michael [2], Li, Mao [3], Kellogg, Elizabeth [4].

Harnessing the power of the herbarium: a specimen-based analysis of morphology and environment in ecologically dominant grasses.

Herbaria contain a cumulative sample of the world’s flora, assembled by thousands of people over several hundred years. In recent decades, advances in computation, DNA sequencing, and image manipulation have allowed us to more fully capitalize on this resource. Using herbarium material from the Missouri Botanical Garden and the Royal Botanic Garden at Kew, we conducted a species-level analysis of a major clade in the grass tribe Andropogoneae, which includes dominant species of the grasslands of Africa, south Asia, Australia, and the Americas, from the genera Andropogon, Schizachyrium, Hyparrhenia, and several other groups. We imaged 188 of the 250 available species, representing approximately 75% of the clade. Specimens were georeferenced and climatic variables were extracted for each. Using a combination of semi- and fully automated image analysis methods, we extracted morphological characters of the spikelets and correlated these with environmental variables. We are currently generating chloroplast genome sequences to correct for phylogenetic covariance and here present an analysis of a subset of 81 species, representing the power of this approach. In addition to taxonomic/phylogenetic observations, we find all morphological and ecological characters homoplasious but variable among clades. For example, sessile spikelet length is positively correlated with awn length when all accessions are considered, but when separated by clade, the relationship is positive for five sub-clades and negative for three others. We found that macrohair density and pedicel length were negatively correlated with precipitation.

1 - 1 Maybeck Place, Principia College, Elsah, IL, 62028, United States
2 - The University of Alabama, Biological Sciences, 300 Hackberry Lane, Tuscaloosa, Alabama, 35487, United States
3 - Donald Danforth Plant Science Center, 975 North Warson Rd, St. Louis, MO, 63132, USA
4 - Donald Danforth Plant Science Center, 975 North Warson Road, St. Louis, MO, 63132, United States

Keywords:
Andropogoneae
Herbaria
morphology
environment
Andropogon
Schizachyrium
Hyparrhenia.

Presentation Type: Colloquium Presentations
Session: C10, Revolutionizing Systematics: Herbaria in the Genomics Age
Location: 103/Mayo Civic Center
Date: Wednesday, July 25th, 2018
Time: 10:30 AM
Number: C10010
Abstract ID:387
Candidate for Awards:None