TITLE

Genetic variation of Populus tremuloides in ecophysiological responses to CO2 elevation

AUTHOR(S)
Ning Liu; Qing-Lai Dang; Parker, William H.
PUB. DATE
February 2006
SOURCE
Canadian Journal of Botany;Feb2006, Vol. 84 Issue 2, p294
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
To investigate the genetic variation of trembling aspen (Populus tremuloides Michx.) in ecophysiological responses to [CO2] elevation, 1-year-old seedlings of four provenances (three families per provenance) from northwestern Ontario were exposed to three [CO2] levels in the greenhouse: ambient (360 ppm), 1.5 × ambient (540 ppm), and 2 × ambient (720 ppm). Biomass and foliage gas exchange were examined after 60 d of treatment. [CO2] elevation significantly increased the rate of net CO2 assimilation and photosynthetic water use efficiency. The stimulation was generally greater in the 540 ppm [CO2] than in 720 ppm [CO2]. The 720 ppm [CO2] resulted in a 10% photosynthetic down-regulation, but no down-regulation was detected in the 540 ppm CO2 treatment. The 540 ppm [CO2] (but not the 720 ppm) treatment significantly decreased stomatal conductance and transpiration rate in the provenances from the Great Lakes – St. Lawrence Region but not in those from the Boreal Region. The intercellular to ambient CO2 concentration ratio (Ci/Ca) was significantly higher under 720 ppm [CO2] than under the other two [CO2]. The CO2 elevations generally increased the total and root biomass, and the stimulation was greater in the 540 ppm [CO2] than in the 720 ppm [CO2] treatment. The two provenances from the Great Lakes – St. Lawrence region generally had greater biomasses than those from the boreal region, while there were no significant differences between them in the physiological variables. However, we did not find any significant differences between provenances in the responses of biomass to [CO2] treatments.
ACCESSION #
21197302

 

Related Articles

Share

Read the Article

Courtesy of THE LIBRARY OF VIRGINIA

Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics