title: Mating system variation and assortative mating of sympatric bromeliads (Pitcairnia spp.) endemic to neotropical inselbergs.
abstract: OBJECTIVE
  The mating system is an important component of the complex set of reproductive isolation barriers causing plant speciation. However, empirical evidence showing that the mating system may promote reproductive isolation in co-occurring species is limited. The mechanisms by which the mating system can act as a reproductive isolation barrier are also largely unknown.
  
  
  METHODS
  Here we studied progeny arrays genotyped with microsatellites and patterns of stigma-anther separation (herkogamy) to understand the role of mating system shifts in promoting reproductive isolation between two hybridizing taxa with porous genomes, Pitcairnia albiflos and P. staminea (Bromeliaceae).
  
  
  RESULTS
  In P. staminea, we detected increased selfing and reduced herkogamy in one sympatric relative to two allopatric populations, consistent with mating system shifts in sympatry acting to maintain the species integrity of P. staminea when in contact with P. albiflos.
  
  
  CONCLUSIONS
  Mating system variation is a result of several factors acting simultaneously in these populations. We report mating system shifts as one possible reproductive barrier between these species, acting in addition to numerous other prezygotic (i.e., flower phenology and pollination syndromes) and postzygotic barriers (Bateson-Dobzhansky-Muller genetic incompatibilities).
authors.affiliation: Departamento de Ecologia, IB/UNESP, Rio Claro, SP, 13506-900 Brazil Instituto de Botânica, São Paulo, SP, 04301-012 Brazil.
authors.forename: Clarisse
authors.initials: C
authors.lastname: Palma-Silva
authors.affiliation: Dipartimento di Biologia, Università degli Studi di Napoli Federico II, Naples, 80126 Italy CNR Istituto per la Protezione Sostenibile delle Piante, Firenze, I-50019 Italy.
authors.forename: Salvatore
authors.initials: S
authors.lastname: Cozzolino
authors.affiliation: Ciências Biológicas, CPAN/UFMS, Corumbá-MS, 79304-902 Brazil.
authors.forename: Gecele Matos
authors.initials: GM
authors.lastname: Paggi
authors.affiliation: Department of Biology, University of Fribourg, Fribourg, Switzerland Department of Botany and Biodiversity Research, University of Vienna, Vienna, A-1030 Austria.
authors.forename: Christian
authors.initials: C
authors.lastname: Lexer
authors.affiliation: Departamento de Botânica, CCS/IB/UFRJ, Rio de Janeiro, RJ, 21941-590 Brazil.
authors.forename: Tânia
authors.initials: T
authors.lastname: Wendt
mesh_terms: D001938:Brazil; D031229:Bromeliaceae / Q000033:anatomy & histology* / Q000235:genetics / Q000502:physiology*; D035264:Flowers / Q000033:anatomy & histology; D049810:Genetic Speciation; D005838:Genotype; D018895:Microsatellite Repeats; D012098:Reproduction; D060047:Reproductive Isolation; D061350:Sympatry
keywords: Bromeliaceae; asymmetric introgression; breeding system; evolution of selfing; herkogamy; hybridization; progeny array; reinforcement; reproductive biology; reproductive isolation; speciation