EFFECT OF PUTRESCINE-SYNTHESIS INHIBITORS ON SOMATIC EMBRYOGENESIS INHAZELNUT

We examined the involvement of polyamines in somatic embryogenesis in hazelnut Corylus avellana L. var. Casina. The formation of somatic emb ryos and the levels of various polyamines were determined after cultur e of cotyledonary leaves in the presence or absence of various inhibit ors of putrescine synthesis, viz., difluoromethyl-ornithine (DFMO), D- arginine (D-Arg) and canavanine(Can). D-Arg and Can decreased embryoge nic induction percentages. To examine whether this was a specific effe ct or a general inhibitory effect, we also determined the effect of th e inhibitors on the outgrowth of axillary buds from nodal shoot segmen ts. In this assay, only Can had an inhibitory effect. The measurements of endogenous polyamine levels showed that in hazelnut, somatic embry ogenesis decreased when putrescine and spermidine were simultaneously reduced, but was not affected by lower level of only putrescine.