title: Effects of seed cryopreservation, stratification and scarification on germination for five rare species of pitcher plants.
abstract: BACKGROUND
  Habitat loss and over collection have caused North American pitcher plants to become rare, including U.S. federally endangered Sarracenia alabamensis and S. oreophila, and S. leucophylla, S. psittacina and S. purpurea spp. venosa, endangered in several states.
  
  
  OBJECTIVE
  To develop reliable seed cryopreservation protocols for endangered Sarracenia species enabling similar germination percentages before and after storage in liquid nitrogen (LN) either in vivo or using in vitro tools.
  
  
  METHODS
  Seed germination pre- and post-cryopreservation were compared following seed drying with germination in soil, aseptic environment with wet filter paper or enriched medium, and using scarification or stratification for dormancy removal.
  
  
  RESULTS
  After cryostorage, germination in vitro (1/6- or 1/3-strength MS medium) increased compared to germination on peat moss. Germination pre- and post-cryopreservation was similar for S. alabamensis and S. oreophila when seeds were stratified and grown in vitro. S. leucophylla and S. psittacina also showed high germination after cryopreservation when germinated on medium following stratification.
  
  
  CONCLUSIONS
  Rapid liquid nitrogen exposure and rewarming induced seed coat cracking that damaged seeds, likely allowing internal damage during acid scarification and microbial entry during germination in non-sterile environments.
authors.forename: Sruti
authors.initials: S
authors.lastname: Khanna
authors.forename: Heather
authors.initials: H
authors.lastname: Jenkins
authors.forename: Kylie
authors.initials: K
authors.lastname: Bucalo
authors.forename: Ron O
authors.initials: RO
authors.lastname: Determann
authors.forename: Jennifer M
authors.initials: JM
authors.lastname: Cruse-Sanders
authors.forename: Gerald S
authors.initials: GS
authors.lastname: Pullman
mesh_terms: D000222:Adaptation, Physiological; D003080:Cold Temperature; D003247:Conservation of Natural Resources; D015925:Cryopreservation; D056727:Endangered Species; D018525:Germination / Q000187:drug effects / Q000502:physiology*; D009584:Nitrogen; D009656:North America; D052583:Sarraceniaceae / Q000187:drug effects / Q000502:physiology*; D012639:Seeds / Q000187:drug effects / Q000502:physiology*; D013464:Sulfuric Acids / Q000494:pharmacology
chemical_list: D013464:Sulfuric Acids; D009584:Nitrogen; C033158:sulfuric acid