title: Improved cryopreservation of oil palm (Elaeis guineensis Jacq.) polyembryoids using droplet vitrification approach and assessment of genetic fidelity.
abstract: In the present study, polyembryoids of oil palm (Elaeis guineensis Jacq.) were cryopreserved with successful revival of 68 % for the first time using the droplet vitrification technique. Excised polyembryoids (3-5-mm diameter) from 3-month-old in vitro cultures were pre-cultured for 12 h in liquid Murashige and Skoog medium supplemented with 0.5 M sucrose. The polyembryoids were osmoprotected in loading solution [10% (w/v) dimethyl sulphoxide (DMSO) plus 0.7 M sucrose] for 30 min at room temperature and then placed on aluminium strips where they were individually drenched in chilled droplets of vitrification solution (PVS2) [30% (w/v) glycerol plus 15% (w/v) ethylene glycol (EG) plus 15% (w/v) DMSO plus 0.4 M sucrose] for 10 min. The aluminium strips were enclosed in cryovials which were then plunged quickly into liquid nitrogen and kept there for 1 h. The polyembryoids were then thawed and unloaded (using 1.2 M sucrose solution) with subsequent transfer to regeneration medium and stored in zero irradiance. Following for 10 days of storage, polyembryoids were cultured under 16 h photoperiod of 50 μmol m(-2) s(-1) photosynthetic photon flux density, at 23 ± 1 °C. Post-thaw growth recovery of 68% was recorded within 2 weeks of culture, and new shoot development was observed at 4 weeks of growth. Scanning electron microscopy revealed that successful regeneration of cryopreserved polyembryoids was related to maintenance of cellular integrity, presumably through PVS2 exposure for 10 min. The present study demonstrated that cryopreservation by droplet vitrification enhanced the regeneration percentages of oil palm in comparison with the conventional vitrification method previously reported.
authors.affiliation: Department of Crop Science, Faculty of Agriculture, Universiti Putra Malaysia, 43400, Serdang, Selangor, Malaysia.
authors.forename: Saikat
authors.initials: S
authors.lastname: Gantait
authors.forename: Uma Rani
authors.initials: UR
authors.lastname: Sinniah
authors.forename: Periasamy
authors.initials: P
authors.lastname: Suranthran
authors.forename: Sharrmila Rengeswari
authors.initials: SR
authors.lastname: Palanyandy
authors.forename: Sreeramanan
authors.initials: S
authors.lastname: Subramaniam
mesh_terms: D015925:Cryopreservation / Q000379:methods*; D008855:Microscopy, Electron, Scanning / Q000379:methods*; D000073878:Palm Oil; D010938:Plant Oils / Q000737:chemistry*; D058439:Plant Somatic Embryogenesis Techniques / Q000379:methods*; D058989:Vitrification
chemical_list: D010938:Plant Oils; D000073878:Palm Oil