title: Plasticity to salinity and transgenerational effects in the nonnative shrub Baccharis halimifolia: Insights into an estuarine invasion.
abstract: Abiotic constraints act as selection filters for plant invasion in stressful habitats. Adaptive phenotypic plasticity and transgenerational effects play a major role in colonization of heterogeneous habitats when the scale of environmental variation is smaller than that of gene flow. We investigated how plasticity and parental salinity conditions influence the performance of the invasive dioecious shrub Baccharis halimifolia, which replaces heterogeneous estuarine communities in Europe with monospecific and continuous stands.
  
  
  
  In two greenhouse experiments, we grew plants derived from seeds and cuttings collected through interspersed patches differing in edaphic salinity from an invasive population. We estimated parental environmental salinity from leaf Na(+) content in parental plants, and we measured fitness and ion homeostasis of the offspring grown in contrasting salinity conditions.
  
  
  
  Baccharis halimifolia tolerates high salinity but experiences drastic biomass reduction at moderate salinity. At moderate salinity, responses to salinity are affected by the parental salinity: flowering initiation in seedlings and male cuttings is positively correlated with parental leaf Na(+) content, and biomass is positively correlated with maternal leaf Na(+) in female cuttings and seedlings. Plant height, leaf production, specific leaf area, and ionic homeostasis at the low part of the gradient are also affected by parental salinity, suggesting enhanced shoot growth as parental salinity increases.
  
  
  
  Our results support plasticity to salinity and transgenerational effects as factors with great potential to contribute to the invasive ability of B. halimifolia through estuarine communities of high conservation value.
authors.affiliation: Department of Plant Biology and Ecology, University of the Basque Country, UPV/EHU 48080 Bizkaia, Spain Ikerbasque, Basque Foundation for Science 48160 Bilbao, Spain lidia.cano@ehu.eus.
authors.forename: Lidia
authors.initials: L
authors.lastname: Caño
authors.affiliation: Department of Plant Biology and Ecology, University of the Basque Country, UPV/EHU 48080 Bizkaia, Spain.
authors.forename: Teresa
authors.initials: T
authors.lastname: Fuertes-Mendizabal
authors.affiliation: Department of Plant Biology and Ecology, University of the Basque Country, UPV/EHU 48080 Bizkaia, Spain.
authors.forename: Gonzalo
authors.initials: G
authors.lastname: García-Baquero
authors.affiliation: Department of Plant Biology and Ecology, University of the Basque Country, UPV/EHU 48080 Bizkaia, Spain.
authors.forename: Mercedes
authors.initials: M
authors.lastname: Herrera
authors.affiliation: Department of Plant Biology and Ecology, University of the Basque Country, UPV/EHU 48080 Bizkaia, Spain.
authors.forename: M Begoña
authors.initials: MB
authors.lastname: González-Moro
mesh_terms: D031175:Baccharis / Q000254:growth & development / Q000502:physiology*; D018533:Biomass; D063366:Estuaries; D058865:Introduced Species; D016014:Linear Models; D018515:Plant Leaves / Q000033:anatomy & histology / Q000737:chemistry; D054712:Salinity; D012639:Seeds / Q000502:physiology; D012964:Sodium / Q000032:analysis
chemical_list: D012964:Sodium
keywords: Asteraceae; alien; cuttings; parental effects; plastic response; salt stress; seedlings; woody plant