Propagation of Ornamental Plants
23(1): 3-12, 2023
ASSESSMENT OF THE THREATENED SPECIES DIANTHUS NARDIFORMIS JANKA AFTER SLOW-GROWTH CULTURE AND CRYOPRESERVATION AS EX SITU CONSERVATION APPROACH
Irina Holobiuc, Monica Mitoi*, Rodica Catană, Florența Helepciuc, and Maximilian Carmen
Institute of Biology Bucharest of Romanian Academy, 296 Splaiul Independentei str.,
P. O. Box 56-53, 060031 Bucharest, Romania,
Ex situ plants` long-term conservation can be accomplished through cryopreservation procedures applied on meristems or somatic embryos. To achieve long-term preservation in the rare endangered species Dianthus nardiformis Janka, embryogenic aggregates, maintained for five years in slow growth culture were used for cryopreservation applying an encapsulation-dehydration protocol. Further, regenerants derived from slow growth culture and those recovered after cryopreservation were evaluated using allozymes and ISSR markers. A successful protocol for cryopreservation of synthetic seeds was obtained, being validated by a high recovery rate (79.1%) after cryopreservation. The rate of polymorphism detected in the clones regenerated from cryopreserved synthetic seeds was lower (20.2%) compared with clones derived from slow growth cultures (30.8%). The isoenzyme and ISSR patterns showed changes which did not appear to be associated with the cryopreservation, but rather being related to the slow growth culture maintenance during long period.
Key words: dehydration-encapsulation protocol, genetic variability, ISSR markers, long term preservation, somatic embryogenesis, synthetic seeds