Light-induced biophotonic emission from plant tissues

The emission of biophotons in the visible range, following a delay time of 2-200 seconds after exposure to light, has been measured in germinating seeds, roots, flowers, leaves, and cells. It was found that the biophotonic signals are reproducible and light-induced. The observed signals from germinating seeds of Phaseolus aures and decaying leaves of Eucalyptus are presented to show that the signals have characteristic kinetics and intensity. The kinetics of the signal was found to be independent of the stage of growth or decay, though its intensity varied with biological factors. The kinetics in the first minute is characterized by a single exponential decay term while that in the region t less than or equal to 200 s is characterized by two exponentials. The variation in the intensity of the signal with mass, state of hydration, and growth, and the effect of inhibitors in various systems (e.g. leaves, lichen, Chlorella) are reported.