Oecologia

, Volume 139, Issue 4, pp 487–494

Natural selection on light response curve parameters in the herbaceous annual, Impatiens capensis

Authors

    • Department of Ecology and Evolutionary BiologyUniversity of Connecticut
    • Harvard University Herbaria
    • Harvard University Herbaria
  • John R. Stinchcombe
    • Department of Ecology and Evolutionary BiologyBrown University
  • Kent E. Holsinger
    • Department of Ecology and Evolutionary BiologyUniversity of Connecticut
  • Johanna Schmitt
    • Department of Ecology and Evolutionary BiologyBrown University
Ecophysiology

DOI: 10.1007/s00442-004-1553-z

Cite this article as:
Heschel, M.S., Stinchcombe, J.R., Holsinger, K.E. et al. Oecologia (2004) 139: 487. doi:10.1007/s00442-004-1553-z

Abstract

We tested for genetic variation in light response curves and their acclimation to sun versus shade in recombinant inbred lines (RILs) of the annual species Impatiens capensis derived from a cross between sun and shade populations. We exposed replicates of 49 RILs to experimentally manipulated light levels (open versus shade) in a greenhouse and measured photosynthetic light response curves, height, biomass, and reproduction. Plants were taller in the shade treatment, but we were unable to detect differences between light treatments (i.e., acclimation) in the maximal rate of photosynthesis, the light compensation point, or the quantum efficiency of photosynthesis. Genotypic selection analyses indicated that higher maximal rates of carbon assimilation and higher light compensation points (typical of sun-acclimated light curves) were favored by natural selection in both light treatments. Thus, it appears that the pattern of selection on photosynthetic parameters may not depend on light environment in this species.

Keywords

Photosynthetic acclimation responsesSun–shade ecotypesImpatiens capensisNatural selection

Copyright information

© Springer-Verlag 2004