title: Cryopreservation of immature seeds of Ponerorchis graminifolia var. suzukiana by vitrification.
abstract: Ponerorchis graminifolia var. suzukiana is a terrestrial orchid that is an endangered species native to Japan, and it germinates more readily in immature seeds than in mature seeds. To preserve this orchid, an efficient protocol was established for the cryopreservation of immature seeds of P. graminifolia var. suzukiana. When immature seeds of 6 weeks after pollination, which showed higher germination and protocorm formation than mature seeds, were precultured on New Dogashima (ND) medium with 0.3M sucrose for 3 days and cryopreserved by vitrification method (treated with PVS2 for 60 min), the viability after preservation as assessed with 2,3,5-triphenyltetrazolium chloride staining test was about 86%. Immature seeds thus treated showed equal rates of germination and protocorm formation to the untreated control immature seeds, and they developed into normal plantlets on ND medium.
authors.affiliation: Laboratory of Plant Cell Technology, Faculty of Horticulture, Chiba University, 648 Matsudo, Matsudo-City, Chiba, 271-8510, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Hirano
authors.forename: K
authors.initials: K
authors.lastname: Ishikawa
authors.forename: M
authors.initials: M
authors.lastname: Mii
mesh_terms: D018929:Cell Culture Techniques / Q000379:methods; D015925:Cryopreservation / Q000379:methods*; D018525:Germination; D006801:Humans; D029595:Orchidaceae; D012639:Seeds