title: Diversity of leaf traits related to productivity in 31 Populus deltoides x Populus nigra clones.
abstract: To test if some leaf parameters are predictors of productivity in a range of Populus deltoides (Bartr.) Marsh. x P. nigra L. clones, we assessed leaf traits and productivity in 2-month-old rooted cuttings from 31 clones growing in 4-l pots in a greenhouse, under conditions of controlled temperature and optimal irrigation. We evaluated four groups of variables describing (1) productivity (total biomass), (2) leaf growth (total leaf number increment and total leaf area increment rate), (3) leaf structure (specific leaf area and nitrogen and carbon contents) and (4) carbon isotope discrimination (delta), which is negatively correlated with time-integrated water-use efficiency. High-yielding clones did not necessarily display high leaf growth rates, but they displayed a larger total leaf area, lower specific leaf area and lower leaf nitrogen concentration than clones with low productivity. Total leaf area was mainly controlled by maximal individual leaf area and total leaf area increment rate (r = 0.51 and 0.56, respectively). Carbon isotope discrimination did not correlate with total biomass, but it was associated with total number of leaves and total leaf area increment rate (r = 0.39 and 0.45, respectively). Therefore, leaf area and specific leaf area were better indicators of productivity than leaf growth traits. The observed independence of delta from biomass production provides opportunities for selecting poplar clones combining high productivity and high water-use efficiency.
authors.affiliation: Laboratoire de Biologie des Ligneux et des Grandes Cultures, UPRES EA 1207, UFR-Faculté des Sciences, Université d'Orléans, rue de Chartres, BP 6759, 45067 Orléans Cedex 02, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Marron
authors.forename: Marc
authors.initials: M
authors.lastname: Villar
authors.forename: Erwin
authors.initials: E
authors.lastname: Dreyer
authors.forename: Didier
authors.initials: D
authors.lastname: Delay
authors.forename: Eric
authors.initials: E
authors.lastname: Boudouresque
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Petit
authors.forename: Francis M
authors.initials: FM
authors.lastname: Delmotte
authors.forename: Jean-Marc
authors.initials: JM
authors.lastname: Guehl
authors.forename: Franck
authors.initials: F
authors.lastname: Brignolas
mesh_terms: D018533:Biomass; D001699:Biometry; D002244:Carbon / Q000378:metabolism; D002247:Carbon Isotopes; D014644:Genetic Variation; D009584:Nitrogen / Q000378:metabolism; D018515:Plant Leaves / Q000254:growth & development*; D018517:Plant Roots / Q000254:growth & development; D018547:Plant Stems / Q000254:growth & development; D032107:Populus / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D014867:Water / Q000378:metabolism*
chemical_list: D002247:Carbon Isotopes; D014867:Water; D002244:Carbon; D009584:Nitrogen