You are here:
MONOTERPENE LEVELS IN NEEDLES OF DOUGLAS-FIR EXPOSED TO ELEVATED CO2 AND TEMPERATURE
Snow, M. D., R. R. Bard, D M. Olszyk, L. M. Minster, A. N. Hager, AND D T. Tingey. MONOTERPENE LEVELS IN NEEDLES OF DOUGLAS-FIR EXPOSED TO ELEVATED CO2 AND TEMPERATURE. PHYSIOLOGIA PLANTARUM. Blackwell Publishing, Denmark, 117:352-358, (2003).
Levels of monoterpenes in current year needles of douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedlings were measured at the conclusion of four years of exposure to ambient or elevated CO2 (+ 179 mmol.mol-1), and ambient or elevated temperature (+ 3.5 C). Eleven monoterpenes were identified and quantified using gas chromatography/flame ionization detector/mass spectroscopy, with eight of these compounds regularly occurring in all trees examined. Elevated CO2 exposure reduced the levels of all eight of the regularly detected compounds. Total monoterpene production was reduced by 52% (p<0.05). Elevated temperature also significantly reduced monoterpene levels (p<0.05). The combination of elevated temperatures and elevated CO2 resulted in a 64% reduction in total monoterpenes (p<0.05). Two-way ANOVA showed no significant temperature X CO2 interaction. It is hypothesized that seasonal reductions in needle monoterpene pools under elevated CO2 conditions may be due to a combination of competing carbon sinks, including increased carbon flux through the roots.