JXB Advance Access published online on September 4, 2007
Journal of Experimental Botany, doi:10.1093/jxb/erm177
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
© 2007 The Author(s).
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/2.0/uk/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.This paper is available online free of all access charges (see http://jxb.oxfordjournals.org/open_access.html for further details)
RESEARCH PAPER |
The influence of temperature on within-canopy acclimation and variation in leaf photosynthesis: spatial acclimation to microclimate gradients among climatically divergent Acer rubrum L. genotypes
1Department of Horticulture and Landscape Architecture, Shepardson Building, Colorado State University, Fort Collins, CO 80523–1173, USA
2Department of Horticulture, Clemson University, Clemson, SC 29634-0319, USA
3Department of Forestry and Natural Resources, Clemson University, Clemson, SC, USA 29634-0317, USA
* To whom correspondence should be addressed. E-mail: bauerle{at}clemson.edu
Leaf gas exchange and temperature response were measured to assess temperature acclimation within a tree canopy in climatically contrasting genotypes of Acer rubrum L. Over the course of two 50 d continuous periods, growth temperature was controlled within tree crowns and the steady-state rate of leaf gas exchange was measured. Data were then modelled to calculate the influence of genotype variation and vertical distribution of physiological activity on carbon uptake. The maximal rate of Rubisco carboxylation (Vcmax), the maximum rate of electron transport (Jmax), leaf dark respiration rate (Rd), maximum photosynthesis (Amax), and the CO2 compensation point (
) increased with temperature during both (i) a constant long-term (50 d) daytime temperature or (ii) ambient daytime temperature with short-term temperature control (25–38 °C). In addition, within-crown variation in the temperature response of photosynthesis and Rd was influenced by acclimation to local microclimate temperature gradients. Results indicated that carbon uptake estimates could be overestimated by 22–25% if the vertical distribution of temperature gradients is disregarded. Temperature is a major factor driving photosynthetic acclimation and within-crown gas exchange variation. Thus, this study established the importance of including spatial acclimation to temperature- and provenance-, ecotype-, and/or genotype-specific parameter sets into carbon uptake models.
Key words: Global change, photosynthetic capacity, temperature acclimation, temperature response
Received 11 June 2007; Revised 21 June 2007 Accepted 9 July 2007
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  M. A. Shahba and W. L. Bauerle Growth temperature modulates the spatial variability of leaf morphology and chemical elements within crowns of climatically divergent Acer rubrum genotypes Tree Physiol, July 1, 2009; 29(7): 869 - 877. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. F. Reynolds, W. L. Bauerle, and Y. Wang Simulating carbon dioxide exchange rates of deciduous tree species: evidence for a general pattern in biochemical changes and water stress response Ann. Bot., June 30, 2009; (2009) mcp156v1. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 W. L. Bauerle, J. D. Bowden, G. G. Wang, and M. A. Shahba Exploring the importance of within-canopy spatial temperature variation on transpiration predictions J. Exp. Bot., June 26, 2009; (2009) erp206v1. [Abstract] [Full Text] [PDF]
|
|