Gibberellin‐stimulated Nucleic Acid Metabolism in the Cotyledons and Embryonic Axes of Corylus Avellana (L.) Seeds

Summary Gibberellin treatment of intact hazel seeds stimulated 14C incorporation from [8‐14C] adenine into RNA and DNA of both cotyledons and embryonic axes compared with the corresponding water controls. This stimulation was apparent in the embryonic axes after only 12 hours treatment, but was not detected in the cotyledons until after 48 hours gibberellin treatment. The 14C incorporation into nucleic acids of cotyledons isolated from air‐dry seeds was also shown to be stimulated by gibbereliin treatment. It is concluded that the first effect of gibberellin on the intact hazel seed is on the embryonic axis, but that a second response occurs in the cotyledons, which is to some extent independent of the embryonic axis. It is suggested that the results for the cotyledons represent gibberellin‐stimulated nucleic acid synthesis, including the formation of specific mRNA required for the production of enzymes concerned with reserve lipid mobilization.