Embryogenic cultures of plants are exposed to various stress factors both in vitro and during cryostorage. In order to safely include the plant material obtained by somatic embryogenesis in combination with cryopreservation for breeding programs, it is necessary to monitor its genetic stability. The aim of the present study was the assessment of somaclonal variation in plant material obtained from embryogenic cultures of Picea abies (L.) Karst. and P. omorika (Pancic) Purk. maintained in vitro or stored in liquid nitrogen by the pregrowth-dehydration method. The analysis of genetic confoimity with using microsatellite markers was performed on cotyledonary somatic embryos (CSE), germinating somatic embryos (GSE) and somatic seedlings (SS), obtained from tissues maintained in vitro or from recovered embryogenic tissues (ETc) and CSE obtained after cryopreservation. The analysis revealed changes in the DNA of somatic embryogenesis-derived plant material of both Picea spp. They were found in plant material from 8 out of 10 tested embryogenic lines of P abies and in 10 out of 19 embryogenic lines of P. omorika after in vitro culture. Changes were also detected in plant material obtained after cryopreservation. Somaclonal variation was observed in ETc and CSE of P omorika and at ETv stage of P abies. However, most of the changes were induced at the stage of somatic embryogenesis initiation. These results confirm the need for monitoring the genetic stability of plants obtained by somatic embryogenesis and after cryopreservation for both spruce species.

Centaurium erythraea plants obtained by indirect organogenesis are described in the paper. The plants were initiated from a single adventitious shoot regenerated from callus derived from the cotyledon of a 30-day-old seedling. The shoot was multiplied on MS medium supplemented with IAA (0.1 mg·L-1) and BAP (1.0 mg·L-1). The multiplication rate (28 shoots per culture within 4 weeks) was highest at the first subculture and decreased in further subcultures. The shoots were rooted on MS medium. The effect of IBA (0.1 mg·L-1) on the number of shoots forming roots differed depending on the composition of the basal medium (MS). The rooted shoots were transplanted to soil and grown in a greenhouse with 90% effectiveness. RAPD analysis was done with adventitious shoots of C. erythraea from in vitro culture. In shoots and whole plants regenerated from the callus tissue, secoiridoid content was determined by the HPLC method. We showed significant differences in morphology (leaf size, fresh and dry weight and height of plants) and changes in the DNA profiles as compared to earlier reports for shoot tip-derived shoots and plants of C. erythraea, but the two groups of plants biosynthesized the same qualitative pattern and similar levels of secoiridoids, up to 150 mg·g-1 dry weight; the increased biomass of plants regenerated from callus tissue makes them a better source of secondary metabolites.