|Field, Taylor - ORGAN&EVOLUTION HARVARD|
Submitted to: Plant Physiology Supplement
Publication Type: Abstract Only
Publication Acceptance Date: July 1, 1998
Publication Date: N/A
Technical Abstract: Upon a light-to-dark transition, the PQ pool of Amaranth leaves goes reduced rather than oxidized as measured with leaf chlorophy II fluorescence near the Fo level (apparent Fo). Based on the CO and far-red sensitivity of apparent Fo, the activity reducing the PQ pool in darkness is ascribed to a chlororespiratory electron cycle coupled to NADPH which is the stromal donor reducing PQ. We also measure the diurnal behavior of the apparent Fo rise and CO-sensitivity. Apparent Fo did not rise in leaves early in the morning, while after several hours in the light, the CO-sensibility of apparent Fo was expressed. The possible interactions chlororespiration and starch synthesis and degradation are discussed.