Abstract Detail

Symbioses: Plant, Animal, and Microbe Interactions

Carpenter, Elizabeth Marjorie [1], Dlugosch, Katrina [2].

Growth-defense trade-off in invasive Centaurea solstitialis.

Yellow star-thistle (Centaurea solstitialis) is an invasive annual plant that has caused considerable environmental damage since its establishment in North and South America. Invading populations in California (United States) have evolved increased growth, and show evidence of adaptive evolution in genes associated with defense. We hypothesize that invasive C. solstitialis has evolved larger plant growth while trading off lower investment in defense functions. We tested this hypothesis by comparing immune responses (the oxidative burst) of native and invaded range plant genotypes in response to wounding and exposure to both native range and invaded range bacteria. were. We found that invasive C. solstitialis showed a lowered immune response to wounding and to both invaded and native range bacteria. Immune response was negatively related to plant size, consistent with evolution along a growth-defense trade-off. These results suggest that invasive yellow star-thistle might be benefiting from selection for investment away from defense functions. We are currently investigating the genetic nature of this trade-off by QTL mapping the genetic basis of divergence in both size and immune activity. Future studies will investigate whether C. solstitialis invader evolution could be driven by the release from native range bacteria.

1 - University of Arizona, Ecology and Evolutionary Biology, 1041 E. Lowell St, Tuscon, AZ, 85721, USA
2 - University Of Arizona, ECOL AND EVOL BIOLOGY, P.O. Box 210088, Tucson, AZ, 85721, United States

Keywords:
Microbiome
biotic interactions
invader
yellow starthistle
adaptation
plant defense
tradeoff
growth
Invasive 
invasive plants
microbe
Defense.

Presentation Type: Poster
Session: P, Symbioses: Plant, Animal, and Microbe Interactions Posters
Location: Arizona Ballroom/Starr Pass
Date: Monday, July 29th, 2019
Time: 5:30 PM This poster will be presented at 6:15 pm. The Poster Session runs from 5:30 pm to 7:00 pm. Posters with odd poster numbers are presented at 5:30 pm, and posters with even poster numbers are presented at 6:15 pm.
Number: PSM010
Abstract ID:1004
Candidate for Awards:None