Analysis of Functional Traits on Fitness of Three Species of Helianthus (Sunflowers)

Abstract

It is well established that climate change causes yearly shifts in environmental conditions, but the effects of this variability on plant life are not yet widely understood. It is important to investigate these impacts for the future, as temperatures are expected to continue yielding higher averages than the last 150 years. Identifying morphological features of local flora that can be used to gauge their reproductive health will help to evaluate future impacts of climate change. This project builds upon previous research, assessing the predictive power of two functional traits on the fitness of three species of sunflowers (Helianthus grosseserratus, H. maximiliani, and H. giganteus). Data were collected during the summers of 2020 through 2023 at two different common gardens in Eau Claire. We used linear regression models to assess the influence of leaf water and chlorophyll content on annual fitness (estimated using seed and flowering head counts). Preliminary results indicate leaf water and chlorophyll content are positively related to annual fitness, though they explain only a small proportion of variation, demonstrating the importance of continued research into how traits and fluctuating climatic factors interact to affect plant reproduction.