The effect of elevated CO[sub 2] on high temperature photoinhibition of two eucalypts

Conference · Wed Jun 01 04:00:00 EDT 1994 · Bulletin of the Ecological Society of America; (United States)

OSTI ID:7264802

Roden, J S; Ball, M C ^[1]

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1. Australian National Univ., Canberra (Australia)

A shift in species distribution associated with global climate change may be dependent on the response of seedlings to extreme stress events. Seedlings of Eucalyptus macrorhyncha and E. rossii were grown for 8 weeks in either ambient (350 ppm) or elevated (700 ppm) CO[sub 2] concentrations and subjected to a daily, 3 h, high light (1600 [mu]mol m[sup [minus]2]s[sup [minus]1]) and high temperature (45[degrees]C) photoinhibitory stress period. Seedlings of E. macrorhyncha grown in elevated CO[sub 2] had reduced photosynthetic efficiencies as measured by chlorophyll fluorescence (Fv/Fm) than seedlings grown in ambient CO[sub 2]. However, no significant differences in Fv/Fm were observed between CO[sub 2] treatments for E. rossii. The growth enhancement in elevated CO[sub 2] was less for E. macrorhyncha (41%) than for E. rossi (103%). A decrease in specific leaf area was the principle morphological change associated with growing in an elevated CO[sub 2] environment. There was no discernible differences in photosynthetic acclimation to the high temperature environment for plants grown in either elevated or ambient CO[sub 2] concentrations. In conclusion, elevated CO[sub 2] may exacerbate high temperature photoinhibition, but the response is species specific.

• OSTI ID: 7264802
• Report Number(s): CONF-940894--
• Conference Information: Journal Name: Bulletin of the Ecological Society of America; (United States) Journal Volume: 75:2
• Country of Publication: United States
• Language: English

Related Subjects

560300* -- Chemicals Metabolism & Toxicology
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
BIOLOGICAL EFFECTS
CARBON COMPOUNDS
CARBON DIOXIDE
CARBON OXIDES
CHALCOGENIDES
CHEMICAL REACTIONS
ECOLOGICAL CONCENTRATION
EUCALYPTUSES
MAGNOLIOPHYTA
MAGNOLIOPSIDA
OXIDES
OXYGEN COMPOUNDS
PHOTOCHEMICAL REACTIONS
PHOTOSYNTHESIS
PLANTS
SYNTHESIS
TREES