Rice seedlings germinating in the light in anaerobic environments show the same growth manifestations associated with etiolation of rice seedlings germinating in the dark under stagnant water, namely the failure to synthesize chlorophyll and the failure to manifest normal root and leaf development. This shows that etiolation in this organism can be induced in the light by anaerobiosis. Exposure of the etiolated light-germinated seedlings to normal environmental oxygen concentrations brings about normal greening of the plants as well as normal root and shoot development, thus showing that this phenomenon is reversible.