Effect of Linear Polarized Light on the O2 Uptake in Leaves

Summary 1. Extra O 2 uptake following illumination with linear polarized blue light was studied in DCMU treated leaves of Climatium dendroides, Brachythecium selebrosum (mosses), Elodea canadensis and Lemna trisulca . 2. For both mosses much greater activity of polarized light was found when its E-vector was directed parallel to the leaf axis than when perpendicular to it. Elodea showed only a tendency to such a behaviour. No effect of the direction of polarization plane was found in Lemna . 3. The obtained results can be explained by differences in geometry of cells in the investigated species. They are in good agreement with the assumption that the photoreceptor controlling the extra oxygen uptake blue light dependent is dichroic and oriented parallel to the cell surface.