%0 Journal Article
%T Genetic Variation of Ecophysiological Responses to CO2 in Picea glauca Seedlings
%A Qing-Lai Dang
%A Jodi M. Maepea and William H. ParkerPicea glaucaA
%J The Open Forest Science Journal
%D 2008
%I Bentham Open
%R 10.2174/1874398600801010068]
%X To investigate genetic variation in the response of white spruce (Picea glauca (Moench) Voss) to CO2 elevations, one-year-old seedlings of 11 provenances from Ontario were grown at 360, 530 and 700 ¦̀mol mol-1 CO2 concentrations. After 60 days of treatment, CO2 assimilation rate (A) at growth [CO2] was 32% and 74% higher in the 530 and 700 ¦̀mol mol-1 CO2 treatment, respectively, than in 360 ¦̀mol mol-1 [CO2]. After 90 days, A under 530 and 700¦̀mol mol-1 [CO2] was 141% and 223% greater, respectively, than under 360 ¦̀mol mol-1 [CO2]. When measured at a common [CO2] (360 ¦̀mol mol-1), however, A under 530 and 700 ¦̀mol mol-1 [CO2] treatment was 39% and 53% lower than in the 360 ¦̀mol mol-1 [CO2] treatment, respectively, after 60 days of treatment, and 22 and 35% less, respectively, after 90 days. The CO2 elevations also significantly suppressed Vcamx, Jmax and TPU after 60 days and 90 days of treatment. The [CO2] elevations significantly reduced Stomatal conductance and transpiration after 60 days of treatment, but not after 90 days. gs was 28% and 35% lower under 530 and 700 ¦̀mol mol-1 [CO2], respectively, than under 360 ¦̀mol mol-1 [CO2] after 60 days of treatment. E was 23 and 33% lower under 530 and 700 ¦̀mol mol-1, respectively, than under 360 ¦̀mol mol-1 [CO2]. Photosynthetic water use efficiency (WUE) was 80% and 157% higher after 60 days of treatment and 145% and 196% higher after 90 days, respectively, under 530 and 700 ¦̀mol mol-1 [CO2] than under 360 ¦̀mol mol-1 [CO2]. There were no significant between-provenance differences in any of the above responses; nevertheless, the ecophysiological performance of seedlings was closely correlated with the temperature and precipitation regimes of the seed origin. In addition, provenance significantly affected seedling total biomass, shoot mass, shoot/root ratio and height growth.
%U http://www.benthamscience.com/open/tofscij/articles/V001/68TOFSCIJ.htm