Performance and Secondary Chemistry of Two Hybrid Aspen (Populus tremula L. x Populus tremuloides Michx.) Clones in Long-Term Elevated Ozone Exposure |
| |
Authors: | E. Häikiö M. Makkonen R. Julkunen-Tiitto J. Sitte V. Freiwald T. Silfver V. Pandey E. Beuker T. Holopainen E. Oksanen |
| |
Affiliation: | (1) Department of Environmental Science, University of Kuopio, P.O. Box 1627, 70211 Kuopio, Finland;(2) Department of Systems Ecology, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands;(3) Institute of Ecology, Friedrich Schiller University Jena, Dornburger Strasse 159, 07743 Jena, Germany;(4) Faculty of Biosciences, University of Joensuu, P.O. Box 111, 80101 Joensuu, Finland;(5) Plant Physiology, National Botanical Research Institute, Rana Pratap Marg, Lucknow, 226001, India;(6) Finnish Forest Research Institute Punkaharju Research Unit, Finlandiantie 18, 58450 Punkaharju, Finland |
| |
Abstract: | The effects of moderately elevated ozone (ca. 35 ppb) on the growth and secondary chemistry of the leaves of two soil-grown Finnish hybrid aspen (Populus tremula L. x Populus tremuloides Michx.) clones with different ozone sensitivities were studied at an open-air exposure field in Kuopio, Finland. Stomatal conductance, photosynthetic rate, and chlorophyll fluorescence were measured during the third growing season. Foliar phenolic concentrations, ergosterol concentration of fine roots, and final dry mass of the trees were determined at the end of the third growing season. Elevated ozone increased the ectomycorrhizal status of the fine roots but had no effect on gas exchange or on the final biomass of either of the clones, indicating equal sensitivity to ozone and no effect of elevated ozone on the intraspecific competitive ability of the clones after three growing seasons. However, in agreement with the data from potted plants of the same clones after two growing seasons, significant differences between the clones were found in all parameters measured. A negative correlation between growth and high concentrations of foliar phenolics indicated that allocation to secondary chemistry also was costly in terms of growth under high resource availability. |
| |
Keywords: | Hybrid aspen Clones Ozone Sensitivity Photosynthesis Stomatal conductance Phenolics Flavonol glycosides Salicylates Condensed tannins Competition Ectomycorrhiza |
本文献已被 SpringerLink 等数据库收录! |
|