The effect of ozone on the yellowing process of magnesium-deficient clonal Norway spruce grown under defined conditions

• Published in: Journal of plant physiology Vol. 162; no. 2; pp. 195 - 206
• Main Authors: Siefermann-Harms, Dorothea, Payer, Hans Dieter, Schramel, Peter, Lütz, Cornelius
• Format: Journal Article
• Language: English
• Published: Jena Elsevier GmbH 01.02.2005; Elsevier; Elsevier Science Ltd
• Subjects: Air Pollutants; air pollution; Biological and medical sciences; chlorophyll; Environmental chambers; forest trees; Fundamental and applied biological sciences. Psychology; Light; light harvesting complex; Light-harvesting chlorophyll- a/ b protein complex; magnesium; Magnesium - pharmacology; Mg deficiency; Non agrochemicals pollutants; Oxidative Stress; Ozone; Ozone - pharmacology; photoinhibition; phytochemical efficiency of photosystem II; Phytopathology. Animal pests. Plant and forest protection; Picea - drug effects; Picea - growth & development; Picea - metabolism; Picea abies; Picea abies (L.) Karst; pollutants; Pollution effects and side effects of agrochemicals on crop plants and forest trees. Other anthropogenic factors; Pollution effects. Side effects of agrochemicals; Seasons; tree physiology; Yellowing process; Fv; Environmental chambers; Picea abies (L.) Karst; Chl; Fm; Ozone; DM; Mg deficiency; Yellowing process; PPFD; LHC II; Light-harvesting chlorophyll- a/ b protein complex; Picea abies (L. ) Karst; Forests; Light-harvesting chlorophyll-a/b protein complex; Chlorophyll b; Chlorophyll a; Gymnospermae; Vegetation; Coniferales; Spermatophyta; Picea abies
• ISSN: 0176-1617; 1618-1328
• DOI: 10.1016/j.jplph.2004.06.009

During two vegetation periods, young clonal spruce trees ( Picea abies (L.) Karst.) with sufficient and poor magnesium (Mg) supply were exposed in the environmental chambers of the GSF phytotron to three levels of ozone (daily means: 18–22, 88–130, and 135–190 μg m −3; 10% reduction at night). Previous year's needles were examined at 4-week intervals with respect to their contents of Mg, Ca, K, Mn, N, P, and chlorophyll (Chl), various parameters of Chl fluorescence, and the stability of the isolated light-harvesting Chl- a/ b-protein complex LHC II. The needles of the two nutrition variants contained more than 0.53 or less than 0.27 mg Mg g −1 needle dry matter, respectively. The ratio of variable to maximal Chl- a fluorescence of the dark-adapted needles, Fv/Fm, and the photoinhibitory quenching of Fv after light treatment, SVi.v, were affected by the Mg content of the needles rather than the ozone levels. Changes of the Chl content and the behavior of the LHC II allowed differentiating between a slow process of needle yellowing occurring under Mg deficiency only, and a rapid process of needle yellowing occurring under the combined action of Mg deficiency and ozone pollution. Only the rapid yellowing process was accompanied by destabilization of the LHC II, and the degree of destabilization was correlated with the ozone concentration present in the days before sampling. The results are consistent with observations obtained at a research site in the Central Black Forest (J Plant Physiol 161 (2004) 423).