Changes in the Stoichiometry of Photosystem II Components as an Adaptive Response to High-Light and Low-Light Conditions during Growth

• Published in: Zeitschrift für Naturforschung C. A journal of biosciences Vol. 41; no. 5; pp. 597 - 603
• Main Authors: Wild, Aloysius, Höpfner, Matthias, Rühle, Wolfgang, Richter, Michael
• Format: Journal Article
• Language: English
• Published: Verlag der Zeitschrift für Naturforschung 01.06.1986
• Subjects: Atrazine; Cytochrome f; Light Adaptation; Photosynthetic Unit; Photosystem Stoichiometry
• ISSN: 0939-5075; 1865-7125
• DOI: 10.1515/znc-1986-5-618

The effect of different growth light intensities (60 W·m , 6 W·m ) on the performance of the photosynthetic apparatus of mustard plants (Sinapis alba L.) was studied. A distinct decrease in photosystem II content per chlorophyll under low-light conditions compared to high-light conditions was found. For P-680 as well as for O and O protein the molar ratio between high-light and low-light plants was 1.4 whereas the respective concentrations per chlorophyll showed some variations for P-680 and O on the one and O protein on the other hand. In addition to the study of photosystem II components, the concentrations of PQ, Cyt f, and P-700 were measured. The light regime during growth had no effect on the amount of P-700 per chlorophyll but there were large differences with respect to PQ and Cyt f. The molar ratio for Cyt f and PQ between high- and low-light leaves was 2.2 and 1.9, respectively. Two models are proposed, showing the functional organization of the pigment system and the electron transport chain in thylakoids of high-light and low-light leaves of mustard plants.