title: Cryopreservation of in vitro-grown shoot tips of cassava by encapsulation-vitrification method.
abstract: Shoot tips of cassava (Manihot esculenta Crantz) in vitro plantlets were successfully cryopreserved using the encapsulation-vitrification technique. Nodal cuttings of 5 mm length with one leaf were cultured on modified MS medium in Petri dishes (90 mm x 20 mm) for about 28 days. Excised shoot tips were precultured on sucrose enriched (0.3 M) medium for 16 h, encapsulated and osmoprotected with a mixture of 2 M glycerol and 0.6 M sucrose for 90 min at 25 degree c before dehydration with PVS2 at 0 degree C for 4 h, then plunged in liquid nitrogen. Successfully vitrified shoot tips resumed growth within 3 days, without intermediary callus formation, and developed shoots. Shoot tips sampled from 21 day-old plantlets produced the highest survival of 80 %. The percentage survival of vitrified shoot tips differed from 38 to 80 % depending on the day of excision. The protocol was successfully applied to four cultivars of cassava with about 80 % average percentage of survival.
authors.affiliation: Scientific Equipment Center, Kasetsart University Research and Development Institute, Bangkok 10900, Thailand. rdirmc@ku.ac.th
authors.forename: Rommanee
authors.initials: R
authors.lastname: Charoensub
authors.forename: Dai
authors.initials: D
authors.lastname: Hirai
authors.forename: Akira
authors.initials: A
authors.lastname: Sakai
mesh_terms: D002470:Cell Survival / Q000187:drug effects / Q000502:physiology; D015925:Cryopreservation / Q000379:methods*; D003451:Cryoprotective Agents / Q000494:pharmacology; D002365:Manihot / Q000187:drug effects / Q000502:physiology*; D018520:Plant Shoots / Q000187:drug effects / Q000502:physiology*
chemical_list: D003451:Cryoprotective Agents