title: Fitness consequences of short- and long-distance pollinations in Phlox hirsuta, an endangered species.
abstract: OBJECTIVE
  The persistence of rare and endangered plant species may depend on the distance pollinators travel when dispersing pollen. Pollinations between adjacent plants, which are often genetically similar, can decrease seed set, germination, and/or progeny vigor due to shared S-alleles or inbreeding depression. Interpopulation pollen dispersal is often suggested as a management tool to increase genetic diversity; however, long-distance pollinations also have the potential to decrease fitness.
  
  
  METHODS
  We performed experimental hand pollinations in the field and germination experiments in a growth chamber to determine the effect of intrapopulation pollination distance (1 m, 10 m, and 100 m) on seed set, seed germination, progeny growth, and progeny reproduction in Phlox hirsuta. In addition, we included interpopulation pollinations (6740 m) to determine whether artificial gene flow is a viable management option for this endangered species.
  
  
  RESULTS
  Although pollination distance did not affect the number of healthy seeds produced or the likelihood of radicle emergence, it did significantly affect the ability of germinating seeds to successfully produce cotyledons. Outbreeding depression was observed during seed germination and early seedling development. Seedlings resulting from interpopulation pollinations developed more slowly and were less likely to survive to produce cotyledons than seedlings resulting from all three intrapopulation pollination distances.
  
  
  CONCLUSIONS
  Our results suggest that the success of P. hirsuta does not depend on the distance pollinators travel within populations and that conservation strategies that involve transporting genes between populations can be counterproductive.
authors.affiliation: Department of Organismal and Environmental Biology, Christopher Newport University, 1 Avenue of the Arts, Newport News, Virginia 23606 USA Lauren.Ruane@cnu.edu.
authors.forename: Lauren G
authors.initials: LG
authors.lastname: Ruane
authors.affiliation: Department of Organismal and Environmental Biology, Christopher Newport University, 1 Avenue of the Arts, Newport News, Virginia 23606 USA.
authors.forename: Morgan E
authors.initials: ME
authors.lastname: Dickens
authors.affiliation: Department of Organismal and Environmental Biology, Christopher Newport University, 1 Avenue of the Arts, Newport News, Virginia 23606 USA.
authors.forename: Morgan E
authors.initials: ME
authors.lastname: Wall
mesh_terms: D002140:California; D003247:Conservation of Natural Resources; D056727:Endangered Species; D051456:Gene Flow; D056084:Genetic Fitness; D019684:Magnoliopsida / Q000235:genetics / Q000502:physiology*; D054817:Pollination
keywords: Polemoniaceae; biparental inbreeding; conservation; germination; inbreeding depression; interpopulation gene flow; outbreeding depression