Open AccessChanges in P-700 Oxidation during the Early Stages of the Induction of Photosynthesis
Author(s) -
Jeremy Harbinson,
C. L. Hedley
Publication year - 1993
Publication title -
plant physiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.554
H-Index - 312
eISSN - 1532-2548
pISSN - 0032-0889
DOI - 10.1104/pp.103.2.649
Subject(s) - photosystem , photosynthesis , photosystem ii , sativum , chlorophyll fluorescence , photosystem i , electron flow , pisum , absorbance , p700 , electron transport chain , photochemistry , chemistry , photosynthetic reaction centre , carbon fixation , chlorophyll , biology , botany , chromatography
Following dark adaptation, the response to irradiance of chlorophyll (Chl) fluorescence, the light-induced absorbance change around 820 nm (to measure reaction center Chl of photosystem I [PSI] P-700 oxidation), and CO2 fixation were examined in pea (Pisum sativum L.) leaves under a range of conditions. Initially, P-700 oxidation is restricted by a lack of regeneration of PSI electron acceptors, and the increase of oxidized P-700 (P-700+) that occurs during approximately the first 60 s of irradiation is largely independent of the resistance to electron flow between the two photosystems. Under these conditions, the quantum efficiency for linear electron flow is directly positively related to P-700+ accumulation, which is in contrast to the direct negative correlation that is the most frequently reported relationship between P-700+ accumulation and the quantum efficiency for linear electron flow.