INSTYTUT DENDROLOGII

Abstract: The studies were carried out on seed explants (mature zygotic embryos) of four spruce species: Picea omorika (Pancić) Purk., P. pungens ‘Glauca' Beisnn., P. breweriana S. Watson and P. abies (L.) Karst. The explants required darkness during the induction of embryogenic tissue. Temporary exposure of explants to light did not increase their embryogenic capacity. It was observed that the temperature of 25°C was the optimal for embryogenic tissue induction from mature zygotic embryos of Picea omorika. Cold treatment at 4°C during one week improved embryogenic tissue initiation in the explants of P. pungens ‘Glauca'. Seed explants of Picea omorika produced embryogenic tissue on medium lacking glutamine. Only explants of Picea abies and P. omorika showed embryogenic tissue formation. For effective proliferation of embryogenic tissue in Picea abies and P. omorika it was necessary to supply the medium with 2,4-D (4.5-9 μM) and BA (2.25 μM). Two of three analized lines showed that ABA promote somatic embryo maturation, at the ABA concentration 20 μM in the medium.

Additional key words: maturation, somatic embryos, Norway spruce, Serbian spruce, blue spruce