THE INFLUENCE OF RED LIGHT ON THE PHOTOTROPISM OF AVENA COLEOPTILES

The shift of phototropic dosage-response curves by red light appears to be dependent on the time interval between red light treatment and phototropic induction. Red light enhances the maximum of the first positive curvature when administered before phototropic induction. Its effect, when given after induction, is only evident with plants exposed in addition to red light the day before the experiment.