title: Growth and protection against oxidative stress in young clones and mature spruce trees (Picea abies L.) at high altitudes.
abstract: Clones of Norway spruce (Picea abies L.) were grown for several years on an altitudinal gradient (1750 m, 1150 m and 800 m above sea level) to study the effects of environmental × genetic interactions on growth and foliar metabolites (protein, pigments, antioxidants). Clones at the tree line showed 4.3-fold lower growth rates and contained 60% less chlorophyll (per gram of dry matter) than those at valley level. The extent of growth reduction was clone-dependent. The mortality of the clones was low and not altitude-dependent. At valley level, but not at high altitude, needles of mature spruce trees showed lower pigment and protein concentrations than clones. In general, antioxidative systems in needles of the mature trees and young clones did not increase with increasing altitude. Needles of all trees at high altitude showed higher concentrations of dehydroascorbate than at lower altitudes, indicating higher oxidative stress. In one clone, previously identified as sensitive to acute ozone doses, this increase was significantly higher and the growth reduction was stronger than in the other genotypes. This clone also displayed a significant reduction in glutathione reductase activity at high altitude. These results suggest that induction of antioxidative systems is apparently not a general prerequisite to cope with altitude in clones whose mother plants originated from higher altitudes (about 650-1100 m above sea level, Hercycnic-Carpathian distribution area), but that the genetic constitution for maintenance of high antioxidative protection is important for stress compensation at the tree line.
authors.affiliation: Forstbotanisches Institut, Georg-August Universität Göttingen, Büsgenweg 2, D-37077 Göttingen, Germany e-mail: apolle@gwdg.de, Fax: +49-551-392705, , , , , , DE.
authors.forename: Andrea
authors.initials: A
authors.lastname: Polle
authors.affiliation: Institut für Forstbotanik und Baumphysiologie, Albert-Ludwigs Universität Freiburg, Am Flughafen 17, D-79085 Freiburg, Germany, , , , , , DE.
authors.forename: Lars O
authors.initials: LO
authors.lastname: Baumbusch
authors.affiliation: Fraunhofer Institut für Atmosphärische Umweltforschung, Kreuzeckbahnstrasse 19, D-82467 Garmisch-Partenkirchen, Germany, , , , , , DE.
authors.forename: Christa
authors.initials: C
authors.lastname: Oschinski
authors.affiliation: Institut für Forstbotanik und Baumphysiologie, Albert-Ludwigs Universität Freiburg, Am Flughafen 17, D-79085 Freiburg, Germany, , , , , , DE.
authors.forename: Monika
authors.initials: M
authors.lastname: Eiblmeier
authors.affiliation: Bundesforschungsanstalt für Forst- und Holzwirtschaft, Sieker Landstrasse 2, D-22927 Großhansdorf, Germany, , , , , , DE.
authors.forename: Vivian
authors.initials: V
authors.lastname: Kuhlenkamp
authors.affiliation: Bundesforschungsanstalt für Forst- und Holzwirtschaft, Sieker Landstrasse 2, D-22927 Großhansdorf, Germany, , , , , , DE.
authors.forename: Birgit
authors.initials: B
authors.lastname: Vollrath
authors.affiliation: Bundesforschungsanstalt für Forst- und Holzwirtschaft, Sieker Landstrasse 2, D-22927 Großhansdorf, Germany, , , , , , DE.
authors.forename: Florian
authors.initials: F
authors.lastname: Scholz
authors.affiliation: Institut für Forstbotanik und Baumphysiologie, Albert-Ludwigs Universität Freiburg, Am Flughafen 17, D-79085 Freiburg, Germany, , , , , , DE.
authors.forename: Heinz
authors.initials: H
authors.lastname: Rennenberg
keywords: Genetic variation; Glutathione reductase; Key words Ascorbate; Superoxide dismutase; Tree line growth