Kenney, Amanda, M. , Juenger, Thomas, E. .
Selection on water-use efficiency (WUE) in Ipomopsis aggregata - an analysis of the functional relationships among WUE, other ecological traits, and fitness.
Water-use efficiency (WUE), the ratio of photosynthesis to water loss through transpiration, is a critical physiological trait affecting plant growth and performance. WUE is an interesting trait from an evolutionary and ecological perspective because selection on WUE and other physiological traits is environment-dependent. Additionally, their functional relationships and underlying genetics are not straight forward or well understood. Ipomopsis aggregata (Polemoniaceae) is an ideal species for studying the evolution of physiological variation because it grows across a large elevation gradient throughout multiple habitats. Using an experimental F2 hybrid population of I. aggregata, we addressed whether there is quantitative genetic variation in WUE, and how selection acts on WUE and other functionally-related ecological traits. WUE was measured using leaf carbon isotope composition (δ13C). Other traits measured include leaf nitrogen concentration, specific leaf area, stem diameter, inflorescence height, flower production and fitness. Results show substantial genetic variation in WUE and other ecological traits, and significant effects of WUE on fitness. We analyze the functional relationships among WUE, other ecological traits, and fitness, and discuss implications for patterns of selection on WUE.
Log in to add this item to your schedule
1 - Unversity of Texas at Austin, Section of Integrative Biology, 1 Unversity Station #C0930, Austin, TX, 78712, USA
Presentation Type: Oral Paper:Papers for Topics
Location: Cottonwood A/Snowbird Center
Date: Monday, July 27th, 2009
Time: 8:45 AM