Investigating Phenotypic Plasticity Along Two Axes of Plant Variation in Helianthus

Aleksander Leonardson, Lydia McNabb, Dr. Nora Mitchell, Department of Biology University of Wisconsin-Eau Claire Phillips Science Hall 330 101 Roosevelt Ave Eau Claire, WI 54701

Climate factors, such as temperature and rainfall, affect both leaf investment (measured by specific leaf area, SLA) and plant height, two axes of phenotypic variation. Previous research has found evidence of trait-environment relationships, where taller plants with higher SLA values are associated with hotter and more intensely lit environments. With the onset of temperature increases in many regions, plants found in any specific, whether wild or cultivated, must cope with increased heat and water loss. Here we ask whether plants exhibit phenotypic plasticity regarding SLA and overall height, with weedy perennial sunflowers (Helianthus) as our model study system. Plasticity is how organisms rapidly adjust trait values in response to growing conditions in the environment, as opposed to genetic (evolutionary) change occurring over generations. We established two replicate common gardens separated by approximately 3km in Eau Claire, Wisconsin, each composed of 75 randomly distributed individuals from three perennial sunflower species, H grosseserratus, H giganteus, and H maximiliani. During the growing season we collected leaves and measured SLA, and recorded final plant height. We found substantial phenotypic plasticity in both traits, with higher SLA values and taller plants at one garden compared to the other. Evidence of plasticity in these two important traits, even between two closely related locations, sheds light on the potential for plasticity to act as a mechanism for responding to novel climatic conditions under upcoming climate.

Additional Abstract Information

Presenters: Aleksander Leonardson, Lydia McNabb

Institution: University of Wisconsin - Eau Claire

Type: Poster

Subject: Ecology

Status: Approved

Time and Location

Session: Poster 5
Date/Time: Tue 12:30pm-1:30pm
Session Number: 4116