title: Plant resource-use strategies: the importance of phenotypic plasticity in response to a productivity gradient for two subalpine species.
abstract: OBJECTIVE
  Functional traits are indicators of plant interactions with their environment and the resource-use strategies of species can be defined through some key functional traits. The importance of genetic variability and phenotypic plasticity in trait variations in response to a common environmental change was investigated in two subalpine species.
  
  
  METHODS
  Two species with contrasted resource-use strategies, Dactylis glomerata and Festuca paniculata, were grown along a productivity gradient in a greenhouse experiment. Functional traits of different genotypes were measured to estimate the relative roles of phenotypic plasticity and genetic variability, and to compare their levels of phenotypic plasticity.
  
  
  RESULTS
  Trait variability in the field for the two species is more likely to be the result of phenotypic plasticity rather than of genetic differentiation between populations. The exploitative species D. glomerata expressed an overall higher level of phenotypic plasticity compared with the conservative species F. paniculata. In addition to different amplitudes of phenotypic plasticity, the two species differed in their pattern of response for three functional traits relevant to resource use (specific leaf area, leaf dry matter content and leaf nitrogen content).
  
  
  CONCLUSIONS
  Functional trait variability was mainly the result of phenotypic plasticity, with the exploitative species showing greater variability. In addition to average trait values, two species with different resource-use strategies differed in their plastic responses to productivity.
authors.affiliation: Laboratoire d'écologie alpine, CNRS UMR 5553, Université Joseph Fourier, Grenoble Cedex 9, France.
authors.forename: Fabrice
authors.initials: F
authors.lastname: Grassein
authors.forename: Irène
authors.initials: I
authors.lastname: Till-Bottraud
authors.forename: Sandra
authors.initials: S
authors.lastname: Lavorel
mesh_terms: D000704:Analysis of Variance; D031745:Dactylis / Q000033:anatomy & histology / Q000235:genetics*; D031751:Festuca / Q000033:anatomy & histology / Q000235:genetics*; D014644:Genetic Variation / Q000235:genetics; D005838:Genotype; D010641:Phenotype