Facilitation across stress gradients: the importance of local adaptation

• Published in: Ecology (Durham) Vol. 88; no. 9; pp. 2404 - 2409
• Main Authors: Espeland, E.K, Rice, K.J
• Format: Journal Article
• Language: English
• Published: United States 01.09.2007
• Subjects: abiotic stress; adaptation; Adaptation, Physiological; annuals; Biomass; Environment; Genes, Plant; Genetic Variation; grassland soils; intraspecific competition; Likelihood Functions; mortality; nutrient availability; plant competition; plant density; Plant Physiological Phenomena; Plantago; Plantago - drug effects; Plantago - genetics; Plantago - physiology; Plantago erecta; Population Density; Population Growth; Secologanin Tryptamine Alkaloids - pharmacology; serpentine soils; Soil - analysis; soil fertility; Species Specificity; stress tolerance; California
• ISSN: 0012-9658; 1939-9170
• DOI: 10.1890/06-1217.1

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.