title: Cryopreservation of seeds and in vitro-cultured protocorms of Oncidium bifolium sims. (Orchidaceae) by encapsulation-dehydration.
abstract: Encapsulation-dehydration was employed for cryopreserving seeds and in vitro-cultured protocorms of Oncidium bifolium. Freshly harvested seeds, 120 days after pollination, were encapsulated in beads containing 1/2 MS medium with 3% sucrose and 3% calcium alginate and subsequently pretreated in agitated (80 rpm) liquid medium supplemented with 0.15 M sucrose (24 h) followed by 0.25 M sucrose (48 h), 0.5 M sucrose (24 h) and 0.75 M sucrose (24 h). The beads with seeds were dehydrated with silica gel for 5 h to 19.2% moisture content and immersed in liquid nitrogen for 1 h, thawed at 30 degrees C for 2 min, post-treated using the same series of liquid media [0.5 M sucrose (24 h), 0.25 M sucrose (48 h), 0.15 M sucrose (24 h)], and recultured on 1/2 MS medium with 0.1M sucrose and 0.7% percent agar. As much as 4.8% of the cryopreserved seeds produced complete plants. In-vitro cultured protocorms were successfully cryopreserved following the same procedure, allowing 11.3% of them to produce plants.
authors.affiliation: Facultad de Ciencias Agrarias UNNE, IBONE Instituto de Botanica del Nordeste, CC 209, Corrientes 3400, Argentina.
authors.forename: E
authors.initials: E
authors.lastname: Flachsland
authors.forename: G
authors.initials: G
authors.lastname: Terada
authors.forename: A
authors.initials: A
authors.lastname: Scocchi
authors.forename: H
authors.initials: H
authors.lastname: Rey
authors.forename: L
authors.initials: L
authors.lastname: Mroginski
authors.forename: F
authors.initials: F
authors.lastname: Engelmann
mesh_terms: D015925:Cryopreservation / Q000379:methods*; D003451:Cryoprotective Agents / Q000494:pharmacology; D003681:Dehydration; D004305:Dose-Response Relationship, Drug; D029595:Orchidaceae / Q000187:drug effects / Q000502:physiology*; D012639:Seeds / Q000187:drug effects / Q000502:physiology*; D058428:Silica Gel; D012822:Silicon Dioxide; D013395:Sucrose / Q000494:pharmacology
chemical_list: D003451:Cryoprotective Agents; D013395:Sucrose; D058428:Silica Gel; D012822:Silicon Dioxide