Cryopreservation of Abies alba embryogenic tissues by slow-freezing method

Embryogenic tissues of Abies alba Mill. were cryopreserved using the slow-freezing approach. Four cell lines incubated for 24 h on a medium with 0.5 M sorbitol and pre-treated 5% DMSO. Subsequently, frozen at cooling rate 1 °C min-1 to -40 transferred liquid nitrogen 72 hours. After thawing in water bath 40 °C, cultivated proliferation medium. All tested recovered, but variations regrowth frequencies across noticed (91.66 100%). The recovered showed similar features control 2 (non-pre-treated non-cryopreserved tissues). In accumulation fresh dry mass, no statistically significant differences observed between cultures 2. produced cotyledonary somatic embryos capable germination. Microscopic observations revealed considerable structural changes as consequence cryopreservation procedure. long vacuolated suspensor cells disrupted, mostly meristematic embryonal region survived. typical bipolar structure early has been regained during post-thaw period. Differences cryotolerance also observed.