title: Differences in pollen viability in relation to different deceptive pollination strategies in Mediterranean orchids.
abstract: OBJECTIVE
  To date, current research involving pollen viability has been evaluated in a relatively low number of orchid species. In the present study, we focused on five related Mediterranean orchid genera (Anacamptis, Orchis, Dactylorhiza, Ophrys and Serapias) that are characterized by different types of deceptive pollination.
  
  
  METHODS
  The in vitro germination ability of increasingly aged pollinaria of eight food-, seven sexually and two shelter-deceptive species was evaluated. Pollination experiments on two food-, one sexually and one shelter-deceptive species were also performed and the percentage of embryonate seeds derived from the increasingly aged pollinaria was checked.
  
  
  RESULTS
  All of the examined species showed long-term viabilities (=50 % pollen tube growth) that ranged from 8 to 35 d. Species with the same deceptive pollination strategies exhibited the same pollen viability trends. Interestingly, pollen viabilities of species groups with different deception types have shown significant differences, with sexually and shelter- deceptive species exhibiting a shorter life span than food-deceptive species.
  
  
  CONCLUSIONS
  This study confirms the prolonged germination and fertilization capacities of orchid pollinaria, and to our knowledge is the first report demonstrating a clear relationship between pollen viability and pollination system. It is proposed that this relationship is attributed to the different types of reproductive barriers, pre- or post-zygotic, that characterize Ophrys and Serapias and the food-deceptive species, respectively.
authors: Dipartimento di Ecologia, Università della Calabria, I-87036 Rende, Italy.
authors: Francesca
authors: F
authors: Bellusci
authors: Aldo
authors: A
authors: Musacchio
authors: Rossella
authors: R
authors: Stabile
authors: Giuseppe
authors: G
authors: Pellegrino
mesh_terms: D005638:Fruit / Q000502:physiology; D029595:Orchidaceae / Q000502:physiology*; D011058:Pollen / Q000502:physiology*; D053205:Pollen Tube / Q000502:physiology; D054817:Pollination / Q000502:physiology*; D012639:Seeds / Q000502:physiology