title: Extensive contemporary pollen-mediated gene flow in two herb species, Ranunculus bulbosus and Trifolium montanum, along an altitudinal gradient in a meadow landscape.
abstract: OBJECTIVE
  Genetic connectivity between plant populations allows for exchange and dispersal of adaptive genes, which can facilitate plant population persistence particularly in rapidly changing environments.
  
  
  METHODS
  Patterns of historic gene flow, flowering phenology and contemporary pollen flow were investigated in two common herbs, Ranunculus bulbosus and Trifolium montanum, along an altitudinal gradient of 1200-1800 m a.s.l. over a distance of 1 km among five alpine meadows in Switzerland.
  
  
  RESULTS
  Historic gene flow was extensive, as revealed by Fst values of 0·01 and 0·007 in R. bulbosus and T. montanum, respectively, by similar levels of allelic richness among meadows and by the grouping of all individuals into one genetic cluster. Our data suggest contemporary pollen flow is not limited across altitudes in either species but is more pronounced in T. montanum, as indicated by the differential decay of among-sibships correlated paternity with increasing spatial distance. Flowering phenology among meadows was not a barrier to pollen flow in T. montanum, as the large overlap between meadow pairs was consistent with the extensive pollen flow. The smaller flowering overlap among R. bulbosus meadows might explain the slightly more limited pollen flow detected.
  
  
  CONCLUSIONS
  High levels of pollen flow among altitudes in both R. bulbosus and T. montanum should facilitate exchange of genes which may enhance adaptive responses to rapid climate change.
authors: Ecosystem Management, Department of Environmental Systems Science, Swiss Federal Institute of Technology Zurich (ETH Zurich), Universitaetstrasse 16, Zürich, Switzerland. philippe.matter@env.ethz.ch
authors: Philippe
authors: P
authors: Matter
authors: Chris J
authors: CJ
authors: Kettle
authors: Jaboury
authors: J
authors: Ghazoul
authors: Andrea R
authors: AR
authors: Pluess
mesh_terms: D000222:Adaptation, Physiological / Q000235:genetics; D000531:Altitude; D057231:Climate Change; D017753:Ecosystem; D035264:Flowers / Q000235:genetics; D051456:Gene Flow; D014644:Genetic Variation; D005828:Genetics, Population; D007178:Inbreeding; D011058:Pollen / Q000235:genetics*; D011156:Population Density; D031947:Ranunculus / Q000235:genetics*; D013557:Switzerland; D029921:Trifolium / Q000235:genetics*