title: Linking ethylene to nitrogen-dependent leaf longevity of grass species in a temperate steppe.
abstract: OBJECTIVE
  Leaf longevity is an important plant functional trait that often varies with soil nitrogen supply. Ethylene is a classical plant hormone involved in the control of senescence and abscission, but its role in nitrogen-dependent leaf longevity is largely unknown.
  
  
  METHODS
  Pot and field experiments were performed to examine the effects of nitrogen addition on leaf longevity and ethylene production in two dominant plant species, Agropyron cristatum and Stipa krylovii, in a temperate steppe in northern China.
  
  
  RESULTS
  Nitrogen addition increased leaf ethylene production and nitrogen concentration but shortened leaf longevity; the addition of cobalt chloride, an ethylene biosynthesis inhibitor, reduced leaf nitrogen concentration and increased leaf longevity. Path analysis indicated that nitrogen addition reduced leaf longevity mainly through altering leaf ethylene production.
  
  
  CONCLUSIONS
  These findings provide the first experimental evidence in support of the involvement of ethylene in nitrogen-induced decrease in leaf longevity.
authors.affiliation: State Key Laboratory of Forest and Soil Ecology, Institute of Applied Ecology, The Chinese Academy of Sciences, Shenyang, 110164, China.
authors.forename: Haiyan
authors.initials: H
authors.lastname: Ren
authors.forename: Zhuwen
authors.initials: Z
authors.lastname: Xu
authors.forename: Wenhao
authors.initials: W
authors.lastname: Zhang
authors.forename: Lin
authors.initials: L
authors.lastname: Jiang
authors.forename: Jianhui
authors.initials: J
authors.lastname: Huang
authors.forename: Shiping
authors.initials: S
authors.lastname: Chen
authors.forename: Lixin
authors.initials: L
authors.lastname: Wang
authors.forename: Xingguo
authors.initials: X
authors.lastname: Han
mesh_terms: D031702:Agropyron / Q000502:physiology*; D002681:China; D003035:Cobalt; D017753:Ecosystem; D005030:Ethylenes / Q000378:metabolism*; D009584:Nitrogen / Q000378:metabolism*; D018515:Plant Leaves / Q000502:physiology*
chemical_list: D005030:Ethylenes; D003035:Cobalt; C036216:ethylene; C018021:cobaltous chloride; D009584:Nitrogen
keywords: Agropyron cristatum; Inner Mongolia; Stipa krylovii; ethylene production; grassland; leaf life span; leaf nitrogen; nitrogen addition