Abstract Detail

Molecular Ecology

Dlugosch, Katrina [1].

Genomic Signatures of Adaptation Reveal a Role for a Growth-Defense Trade-Off in Invasion.

With the aid of humans, plant species are now routinely making successful biogeographic transitions to new regions across the globe. Understanding when and where introductions will lead to establishment and spread has become a major goal of both basic and applied research. A growing body of evidence indicates that the genetic makeup of introduced populations and their adaptation to novel environments can shape the fate of introductions. However, non-native populations often have complex introduction histories and experience dramatic allele frequency shifts that need not be adaptive, posing challenges to inferring the contributions of genetic changes to introduction success. We are are addressing these challenges by leveraging population genomic approaches to infer the phylogeographic history of invasions, to identify loci under selection in different biogeographic regions, and to map genetic variants to traits and environments. Our focal study system is the highly invasive grassland plant yellow starthistle (Centaurea solstitialis). Our genomic work is revealing that invading populations in North America might have experienced selection for growth and reproduction at the expense of investment in defense, particularly defense against microbial pathogens. We are now investigating the genetic basis for evolution in growth and in immune function of invading genotypes relative to their native source populations, and we are quantifying biogeographic differences in plant-associated microbial communities that might have selected for shifts along a growth-defense tradeoff. Our work is some of the first to investigate potential links between regional variation in microbiomes, selection for rapid trait evolution, and the success of biogeographic transitions.

1 - University Of Arizona, ECOL AND EVOL BIOLOGY, P.O. Box 210088, Tucson, AZ, 85721, United States

Keywords:
Invase plant species
Population genomics
trait evolution
trade-offs
bioegeographic transitions.

Presentation Type: Oral Paper
Session: MOL1, Molecular Ecology
Location: San Pedro 2/Starr Pass
Date: Wednesday, July 31st, 2019
Time: 1:45 PM
Number: MOL1002
Abstract ID:883
Candidate for Awards:None