title: A comparative study of vitrification and encapsulation-vitrification for cryopreservation of protocorms of Cymbidium eburneum L., a threatened and vulnerable orchid of India.
abstract: Cryopreservation of the threatened orchid Cymbidium eburneum L. was successfully achieved using encapsulation-vitrification and vitrification. Comparing the two methods tested, it was observed that regeneration of protocorms cryopreserved using encapsulation-vitrification was higher than with vitrification. To achieve optimal regrowth after cryopreservation, protocorms were precultured for 24 h with 0.2 M sucrose for vitrification and with 0.7 M sucrose for encapsulation-vitrification, reaching 60 percent and 70 percent regeneration, respectively. With both techniques employed, a 20 min exposure duration to Plant Vitrification Solution 2 (PVS2) led to optimal regeneration after cryopreservation. A maximum of 66 percent regeneration was achieved after cryopreservation using encapsulation-vitrification, whereas it was only 50 percent  after cryopreservation using vitrification. The same regeneration pattern was observed with protocorms cryopreserved using both techniques employed. This is the first report of long-term conservation by cryopreservation of C. eburneum protocorms.
authors.affiliation: Plant Biotechnology Laboratory, Department of Botany, North-Eastern Hill University, Shillong, India.
authors.forename: K
authors.initials: K
authors.lastname: Gogoi
authors.forename: S
authors.initials: S
authors.lastname: Kumaria
authors.forename: P
authors.initials: P
authors.lastname: Tandon
mesh_terms: D015925:Cryopreservation / Q000379:methods*; D003451:Cryoprotective Agents / Q000378:metabolism; D006801:Humans; D007194:India; D029595:Orchidaceae / Q000502:physiology*; D013395:Sucrose / Q000378:metabolism; D058989:Vitrification
chemical_list: D003451:Cryoprotective Agents; D013395:Sucrose