title: Facilitation across stress gradients: the importance of local adaptation.
abstract: While there is some information on genetic variation in response to competition in plants, we know nothing about intraspecific variation in facilitation. Previous studies suggest that facilitation should increase fitness in stressful environments. However, whether a plant experiences an environment as stressful may depend on prior adaptive responses to stressors at a site. Local adaptation to stress at a site may reduce the likelihood of facilitation. Seeds of Plantago erecta from stressful (serpentine soil) and non-stressful (non-serpentine soil) edaphic environments were reciprocally planted into these two soil types. Although competition did not differ significantly among seed sources, there was evidence for a local adaptation effect on facilitation. Non-serpentine seeds planted into serpentine soil exhibited greater individual plant biomass at higher densities. The interaction between population source and growth environment indicates a role for evolutionary processes such as local adaptation in the expression of facilitation in plants.
authors.affiliation: Ecology Graduate Group, Department of Plant Sciences, Mail Stop 1, University of California, Davis, California 95616, USA. ekespeland@ucdavis.edu
authors.forename: E K
authors.initials: EK
authors.lastname: Espeland
authors.forename: K J
authors.initials: KJ
authors.lastname: Rice
mesh_terms: D000222:Adaptation, Physiological; D018533:Biomass; D004777:Environment; D017343:Genes, Plant; D014644:Genetic Variation; D016013:Likelihood Functions; D018521:Plant Physiological Phenomena; D010943:Plantago / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D011156:Population Density; D011158:Population Growth; D046948:Secologanin Tryptamine Alkaloids / Q000494:pharmacology*; D012987:Soil / Q000032:analysis; D013045:Species Specificity
chemical_list: D046948:Secologanin Tryptamine Alkaloids; D012987:Soil; C009244:serpentine (alkaloid)