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1993 (1)
1991 (1)
1Author    Hartwig Hohlfeld1 ', Cornelius Lützb, Dieter StrackaRequires cookie*
 Title    Phosphoenolpyruvate Carboxylase Activity in Norway Spruce Needles: Effects of Air Pollutants under Controlled Conditions  
 Abstract    The effect of mixtures of air pollutants (S 02, N 0 2, O,) on phosphoenolpyruvate carboxylase (PEPCase; EC 4.1.1.31) activities from needles of four-year-old Norway spruce (Picea abies [L.] Karst.) in closed fumi­ gation chambers were analyzed. Three months exposure to high concentrations of 0 3 (1030 |ig/m3) together with S 0 2 (1030 |ig/m3) or N 0 2 (615 |ig/m?) resulted in a dra­ matic increase in PEPCase activities. 
  Reference    Z. Naturforsch. 46c, 502—505 (1991); received January 25/March 51991 
  Published    1991 
  Keywords    Picea abies, Phosphoenolpyruvate Carboxylase (PEPCase), Forest Decline, Air Pollutants, Phytotron 
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 TEI-XML for    default:Reihe_C/46/ZNC-1991-46c-0502_n.pdf 
 Identifier    ZNC-1991-46c-0502_n 
 Volume    46 
2Author    Aloysius Wild, Petra Strobel, Ute FlammersfeldRequires cookie*
 Title    Studies of Components of the Thylakoid Membrane of Undamaged and Damaged Spruce Trees at Different Mountain Sites  
 Abstract    During a five-year period, com ponents o f the thylakoid membrane in needles o f the second generation o f undamaged and damaged trees o f Norway spruce were studied at three different mountain sites in W est Germany. Visible signs o f damage at these sites are a yellowing o f the light-exposed sides o f the needles as well as the loss o f needles. The goal o f this study was to determine damage-induced alterations in com position and physiological reactions o f the thy­ lakoid membranes in spruce needles. In order to meet this purpose, contents o f chlorophyll a and b, electron transport rate o f photosystem II, contents o f the D 1 protein, cytoch rom e/, as well as P-700 were measured. The chlorophyll content in the needles o f the damaged spruce trees was significantly lower than in the needles o f the undamaged trees. In addition to this, the typical annual course o f chlorophyll content was exclusively observed in the needles o f the undamaged spruce trees. If related to dry weight, a drastic reduction o f the electron transport rate and o f the redox com ­ ponents o f the thylakoid membrane was observed due to damage, indicating a degeneration o f the photosynthetic membranes. The contents o f D 1 protein and the photosynthetic electron transport rates were also markedly reduced in the needles o f the damaged trees, when related to chlorophyll content o f thylakoids, suggesting an early and particular impairment o f photo­ system II. The comparison o f spruce trees showing different signs o f damage demonstrates that certain biochemical parameters concerning the photosynthetic membranes (chlorophyll, cytochrom e/ , ratio photosystem II/I) reflect the extent o f damage and are suitable for an early indication o f a beginning, but still invisible damage o f spruce trees. 
  Reference    Z. Naturforsch. 48c, 911 (1993); received June 5/August 27 1993 
  Published    1993 
  Keywords    Chlorophyll, Cytochrome /, D 1 Protein, Forest Decline, P-700, Photosynthetic Electron Transport 
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 TEI-XML for    default:Reihe_C/48/ZNC-1993-48c-0911.pdf 
 Identifier    ZNC-1993-48c-0911 
 Volume    48