title: Comparative seed germination and seedling development of the ghost orchid, Dendrophylax lindenii (Orchidaceae), and molecular identification of its mycorrhizal fungus from South Florida.
abstract: The endangered leafless ghost orchid, Dendrophylax lindenii, one of the most renowned orchids in the world, is difficult to grow under artificial conditions. Published information on asymbiotic and symbiotic (co-culture with a mycobiont) seed germination, seedling anatomy and developmental morphology of this leafless orchid is completely lacking. This information is critical for the development of efficient procedures for ghost orchid production for successful reintroduction.
  
  
  
  Ghost orchid seedling early development stages were morphologically and anatomically defined to compare germination, embryo and protocorm maturation and seedling development during asymbiotic and symbiotic culture with one of two mycorrhizal strains (Dlin-379 and Dlin-394) isolated from ghost orchid roots in situ KEY RESULTS: Seeds symbiotically germinated at higher rates when cultured with fungal strain Dlin-394 than with strain Dlin-379 or asymbiotically on P723 medium during a 10-week culture period. Fungal pelotons were observed in protocorm cells co-cultured with strain Dlin-394 but not Dlin-379. Some 2-year-old seedlings produced multinode inflorescences in vitro Production of keikis from inflorescence nodes indicated the capacity for clonal production in the ghost orchid.
  
  
  
  Ghost orchid embryo and seedling development were characterized into seven stages. Fungal strain Dlin-394 was confirmed as a possible ghost orchid germination mycobiont, which significantly promoted seed germination and seedling development. Internal transcribed spacer sequencing data confirmed that Dlin-394 belongs within the genus Ceratobasidium These results offer the opportunity to examine the benefits of using a mycobiont to enhance in vitro germination and possibly ex vitro acclimatization and sustainability following outplanting.
authors.affiliation: Environmental Horticulture Department, University of Florida, PO Box 110675, Gainesville, FL 32611, USA.|Department of Plant Biotechnology, University of Sciences, 227 Nguyen Van Cu, Ho Chi Minh City, Vietnam.
authors.forename: Nguyen H
authors.initials: NH
authors.lastname: Hoang
authors.affiliation: Environmental Horticulture Department, University of Florida, PO Box 110675, Gainesville, FL 32611, USA micropro@ufl.edu.
authors.forename: Michael E
authors.initials: ME
authors.lastname: Kane
authors.affiliation: Orchid Recovery Program, Biology Department, Illinois College, 1101 West College Avenue, Jacksonville, IL 62650, USA and.
authors.forename: Ellen N
authors.initials: EN
authors.lastname: Radcliffe
authors.affiliation: Orchid Recovery Program, Biology Department, Illinois College, 1101 West College Avenue, Jacksonville, IL 62650, USA and.
authors.forename: Lawrence W
authors.initials: LW
authors.lastname: Zettler
authors.affiliation: Florida Panther National Wildlife Refuge, U.S. Fish and Wildlife Service, 12085 SR 29 South Immokalee, FL 34142, USA.
authors.forename: Larry W
authors.initials: LW
authors.lastname: Richardson
mesh_terms: D004271:DNA, Fungal / Q000235:genetics; D021903:DNA, Ribosomal Spacer / Q000235:genetics; D056727:Endangered Species; D005431:Florida; D018525:Germination / Q000502:physiology*; D038821:Mycorrhizae / Q000235:genetics* / Q000502:physiology; D029595:Orchidaceae / Q000254:growth & development / Q000382:microbiology / Q000502:physiology*; D036226:Seedlings / Q000033:anatomy & histology / Q000254:growth & development; D012639:Seeds / Q000502:physiology; D017422:Sequence Analysis, DNA
chemical_list: D004271:DNA, Fungal; D021903:DNA, Ribosomal Spacer
keywords: Conservation; Polyrrhiza lindenii; flowering; leafless; mycobiont; orchid; reintroduction; restoration