Long‐term exposure to elevated CO₂ and O₃ alters aspen foliar chemistry across developmental stages

• Published in: Plant, cell and environment Vol. 37; no. 3; pp. 758 - 765
• Main Authors: COUTURE, J. J, HOLESKI, L. M, LINDROTH, R. L
• Format: Journal Article
• Language: English
• Published: Oxford Blackwell 01-03-2014; Wiley Subscription Services, Inc
• Subjects: anthropogenic activities; Aspen FACE; Biological and medical sciences; carbon dioxide; Carbon Dioxide - pharmacology; CO2; developmental stages; ecosystems; forest health; forests; Fundamental and applied biological sciences. Psychology; gases; genotype; Glycosides - metabolism; greenhouse gases; Nitrogen - metabolism; ontogeny; ozone; Ozone - pharmacology; phytochemistry; plant biochemistry; Plant Leaves - drug effects; Plant Leaves - growth & development; Populus - drug effects; Populus - growth & development; Populus tremuloides; Proanthocyanidins - metabolism; secondary metabolism; Time Factors; trees; tropospheric ozone; Aspen FACE; Carbon dioxide; Troposphere; Plant ecology; Ozone; Increase; Biochemistry; Exposure; Plant leaf; CO; ontogeny; Salicaceae; tropospheric ozone; Dicotyledones; Angiospermae; Development; Tree; Spermatophyta; Developmental stage; Populus; Secondary metabolism; phytochemistry; secondary metabolism; CO2
• ISSN: 0140-7791; 1365-3040
• DOI: 10.1111/pce.12195

Anthropogenic activities are altering levels of greenhouse gases to the extent that multiple and diverse ecosystem processes are being affected. Two gases that substantially influence forest health are atmospheric carbon dioxide (CO₂) and tropospheric ozone (O₃). Plant chemistry will play an important role in regulating ecosystem processes in future environments, but little information exists about the longitudinal effects of elevated CO₂ and O₃ on phytochemistry, especially for long‐lived species such as trees. To address this need, we analysed foliar chemical data from two genotypes of trembling aspen, Populus tremuloides, collected over 10 years of exposure to levels of CO₂ and O₃ predicted for the year 2050. Elevated CO₂ and O₃ altered both primary and secondary chemistry, and the magnitude and direction of the responses varied across developmental stages and between aspen genotypes. Our findings suggest that the effects of CO₂ and O₃ on phytochemical traits that influence forest processes will vary over tree developmental stages, highlighting the need to continue long‐term, experimental atmospheric change research.