title: Salt effects on functional traits in model and in economically important Lotus species.
abstract: A common stress on plants is NaCl-derived soil salinity. Genus Lotus comprises model and economically important species, which have been studied regarding physiological responses to salinity. Leaf area ratio (LAR), root length ratio (RLR) and their components, specific leaf area (SLA) and leaf mass fraction (LMF) and specific root length (SRL) and root mass fraction (RMF) might be affected by high soil salinity. We characterised L. tenuis, L. corniculatus, L. filicaulis, L. creticus, L. burtii and L. japonicus grown under different salt concentrations (0, 50, 100 and 150 mm NaCl) on the basis of SLA, LMF, SRL and RMF using PCA. We also assessed effects of different salt concentrations on LAR and RLR in each species, and explored whether changes in these traits provide fitness benefit. Salinity (150 mm NaCl) increased LAR in L. burtii and L. corniculatus, but not in the remaining species. The highest salt concentration caused a decrease of RLR in L. japonicus Gifu, but not in the remaining species. Changes in LAR and RLR would not be adaptive, according to adaptiveness analysis, with the exception of SLA changes in L. corniculatus. PCA revealed that under favourable conditions plants optimise surfaces for light and nutrient acquisition (SLA and SRL), whereas at higher salt concentrations they favour carbon allocation to leaves and roots (LMF and RMF) in detriment to their surfaces. PCA also showed that L. creticus subjected to saline treatment was distinguished from the remaining Lotus species. We suggest that augmented carbon partitioning to leaves and roots could constitute a salt-alleviating mechanism through toxic ion dilution.
authors.affiliation: Instituto de Investigaciones Biotecnológicas-Instituto Tecnológico de Chascomús (IIB-INTECH/UNSAM-CONICET), Buenos Aires, Argentina.
authors.forename: P
authors.initials: P
authors.lastname: Uchiya
authors.affiliation: Instituto de Investigaciones Biotecnológicas-Instituto Tecnológico de Chascomús (IIB-INTECH/UNSAM-CONICET), Buenos Aires, Argentina.
authors.forename: F J
authors.initials: FJ
authors.lastname: Escaray
authors.affiliation: IEGEBA, UBA-CONICET - Departamento de Biodiversidad y Biología Experimental, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina.
authors.forename: D
authors.initials: D
authors.lastname: Bilenca
authors.affiliation: Instituto de Investigaciones Biotecnológicas-Instituto Tecnológico de Chascomús (IIB-INTECH/UNSAM-CONICET), Buenos Aires, Argentina.
authors.forename: F
authors.initials: F
authors.lastname: Pieckenstain
authors.affiliation: Instituto de Investigaciones Biotecnológicas-Instituto Tecnológico de Chascomús (IIB-INTECH/UNSAM-CONICET), Buenos Aires, Argentina.
authors.forename: O A
authors.initials: OA
authors.lastname: Ruiz
authors.affiliation: Departamento de Biodiversidad y Biología Experimental, Facultad de Ciencias Exactas y Naturales, PROPLAME-PRHIDEB (CONICET), Universidad de Buenos Aires, Buenos Aires, Argentina.
authors.forename: A B
authors.initials: AB
authors.lastname: Menéndez
mesh_terms: D018533:Biomass; D002244:Carbon / Q000378:metabolism; D008027:Light; D000070116:Lotus / Q000187:drug effects* / Q000502:physiology / Q000528:radiation effects; D010641:Phenotype; D018515:Plant Leaves / Q000187:drug effects / Q000502:physiology / Q000528:radiation effects; D018517:Plant Roots / Q000187:drug effects / Q000502:physiology / Q000528:radiation effects; D018547:Plant Stems / Q000187:drug effects / Q000502:physiology / Q000528:radiation effects; D054712:Salinity; D055049:Salt Tolerance; D012965:Sodium Chloride / Q000494:pharmacology*; D012987:Soil / Q000737:chemistry; D013312:Stress, Physiological
chemical_list: D012987:Soil; D012965:Sodium Chloride; D002244:Carbon
keywords: Leaf area; Lotus spp.; leaf area ratio; leaf mass fraction; root length ratio; root mass fraction; salinity; specific root length