[The effect of low-intensity light from the red and far red regions of the spectrum on Escherichia coli].

The effect of red and far red light having a low intensity on Escherichia coli growth was studied. The growth accelerated when the culture was irradiated with the light at a dose of 1--4 X 10(3) J/m2. When the light of the two spectral regions was used together, the effect depended on the dose and order of the irradiation. It is possible that receptors for red light and for far red light interact in E. coli cells.