[The effect of pre-illumination on the development of plastids in primary leaves of γ-irradiated etiolated bean seedlings].

It has been shown that a short pre-illumination (1-30 min) of etiolated bean seedlings considerably reduces the delay of grana development in the plastids caused by gamma radiation. As in non-irradiated etiolated material the grana formation is stimulated by an equal pre-illumination, it may be concluded that the observed phenomenon is not a consequence of protection or restoration processes but of a photomorphogenic effect which is independent even of gamma radiation.