Salinity tolerances of three succulent halophytes (Tecticornia spp.) differentially distributed along a salinity gradient

L. Moir-Barnetson, Erik Veneklaas, Tim Colmer

    Research output: Contribution to journalArticle

    2 Citations (Scopus)

    Abstract

    We evaluated tolerances to salinity (10-2000mM NaCl) in three halophytic succulent Tecticornia species that are differentially distributed along a salinity gradient at an ephemeral salt lake. The three species showed similar relative shoot and root growth rates at 10-1200mM NaCl; at 2000mM NaCl, T. indica subsp. bidens (Nees) K.A.Sheph and P.G.Wilson died, but T. medusa (K.A.Sheph and S.J.van Leeuwen) and T. auriculata (P.G.Wilson) K.A.Sheph and P.G.Wilson survived but showed highly diminished growth rates and were at incipient water stress. The mechanisms of salinity tolerance did not differ among the three species and involved the osmotic adjustment of succulent shoot tissues by the accumulation of Na+, Cl- and the compatible solute glycinebetaine, and the maintenance of high net K+ to Na+ selectivity to the shoot. Growth at extreme salinity was presumably limited by the capacity for vacuolar Na+ and Cl- uptake to provide sufficiently low tissue osmotic potentials for turgor-driven growth. Tissue sugar concentrations were not reduced at high salinity, suggesting that declines in growth would not have been caused by inadequate photosynthesis and substrate limitation compared with plants at low salinity. Equable salt tolerance among the three species up to 1200mM NaCl means that other factors are likely to contribute to species composition at sites with salinities below this level. The lower NaCl tolerance threshold for survival in T. indica suggests that this species would be competitively inferior to T. medusa and T. auriculata in extremely saline soils.
    Original languageEnglish
    Pages (from-to)739-750
    JournalFunctional Plant Biology
    Volume43
    Issue number8
    DOIs
    Publication statusPublished - 7 Jun 2016

    Fingerprint

    halophytes
    salinity
    shoots
    Bidens
    saline soils
    betaine
    turgor
    osmotic pressure
    salt tolerance
    solutes
    root growth
    water stress
    photosynthesis
    salts
    sugars
    uptake mechanisms
    species diversity
    lakes

    Cite this

    @article{afb6694ef324497fbe9668a91e0675e9,
    title = "Salinity tolerances of three succulent halophytes (Tecticornia spp.) differentially distributed along a salinity gradient",
    abstract = "We evaluated tolerances to salinity (10-2000mM NaCl) in three halophytic succulent Tecticornia species that are differentially distributed along a salinity gradient at an ephemeral salt lake. The three species showed similar relative shoot and root growth rates at 10-1200mM NaCl; at 2000mM NaCl, T. indica subsp. bidens (Nees) K.A.Sheph and P.G.Wilson died, but T. medusa (K.A.Sheph and S.J.van Leeuwen) and T. auriculata (P.G.Wilson) K.A.Sheph and P.G.Wilson survived but showed highly diminished growth rates and were at incipient water stress. The mechanisms of salinity tolerance did not differ among the three species and involved the osmotic adjustment of succulent shoot tissues by the accumulation of Na+, Cl- and the compatible solute glycinebetaine, and the maintenance of high net K+ to Na+ selectivity to the shoot. Growth at extreme salinity was presumably limited by the capacity for vacuolar Na+ and Cl- uptake to provide sufficiently low tissue osmotic potentials for turgor-driven growth. Tissue sugar concentrations were not reduced at high salinity, suggesting that declines in growth would not have been caused by inadequate photosynthesis and substrate limitation compared with plants at low salinity. Equable salt tolerance among the three species up to 1200mM NaCl means that other factors are likely to contribute to species composition at sites with salinities below this level. The lower NaCl tolerance threshold for survival in T. indica suggests that this species would be competitively inferior to T. medusa and T. auriculata in extremely saline soils.",
    author = "L. Moir-Barnetson and Erik Veneklaas and Tim Colmer",
    year = "2016",
    month = "6",
    day = "7",
    doi = "10.1071/FP16025",
    language = "English",
    volume = "43",
    pages = "739--750",
    journal = "Functional Plant Biology",
    issn = "1445-4408",
    publisher = "CSIRO Publishing",
    number = "8",

    }

    Salinity tolerances of three succulent halophytes (Tecticornia spp.) differentially distributed along a salinity gradient. / Moir-Barnetson, L.; Veneklaas, Erik; Colmer, Tim.

    In: Functional Plant Biology, Vol. 43, No. 8, 07.06.2016, p. 739-750.

    Research output: Contribution to journalArticle

    TY - JOUR

    T1 - Salinity tolerances of three succulent halophytes (Tecticornia spp.) differentially distributed along a salinity gradient

    AU - Moir-Barnetson, L.

    AU - Veneklaas, Erik

    AU - Colmer, Tim

    PY - 2016/6/7

    Y1 - 2016/6/7

    N2 - We evaluated tolerances to salinity (10-2000mM NaCl) in three halophytic succulent Tecticornia species that are differentially distributed along a salinity gradient at an ephemeral salt lake. The three species showed similar relative shoot and root growth rates at 10-1200mM NaCl; at 2000mM NaCl, T. indica subsp. bidens (Nees) K.A.Sheph and P.G.Wilson died, but T. medusa (K.A.Sheph and S.J.van Leeuwen) and T. auriculata (P.G.Wilson) K.A.Sheph and P.G.Wilson survived but showed highly diminished growth rates and were at incipient water stress. The mechanisms of salinity tolerance did not differ among the three species and involved the osmotic adjustment of succulent shoot tissues by the accumulation of Na+, Cl- and the compatible solute glycinebetaine, and the maintenance of high net K+ to Na+ selectivity to the shoot. Growth at extreme salinity was presumably limited by the capacity for vacuolar Na+ and Cl- uptake to provide sufficiently low tissue osmotic potentials for turgor-driven growth. Tissue sugar concentrations were not reduced at high salinity, suggesting that declines in growth would not have been caused by inadequate photosynthesis and substrate limitation compared with plants at low salinity. Equable salt tolerance among the three species up to 1200mM NaCl means that other factors are likely to contribute to species composition at sites with salinities below this level. The lower NaCl tolerance threshold for survival in T. indica suggests that this species would be competitively inferior to T. medusa and T. auriculata in extremely saline soils.

    AB - We evaluated tolerances to salinity (10-2000mM NaCl) in three halophytic succulent Tecticornia species that are differentially distributed along a salinity gradient at an ephemeral salt lake. The three species showed similar relative shoot and root growth rates at 10-1200mM NaCl; at 2000mM NaCl, T. indica subsp. bidens (Nees) K.A.Sheph and P.G.Wilson died, but T. medusa (K.A.Sheph and S.J.van Leeuwen) and T. auriculata (P.G.Wilson) K.A.Sheph and P.G.Wilson survived but showed highly diminished growth rates and were at incipient water stress. The mechanisms of salinity tolerance did not differ among the three species and involved the osmotic adjustment of succulent shoot tissues by the accumulation of Na+, Cl- and the compatible solute glycinebetaine, and the maintenance of high net K+ to Na+ selectivity to the shoot. Growth at extreme salinity was presumably limited by the capacity for vacuolar Na+ and Cl- uptake to provide sufficiently low tissue osmotic potentials for turgor-driven growth. Tissue sugar concentrations were not reduced at high salinity, suggesting that declines in growth would not have been caused by inadequate photosynthesis and substrate limitation compared with plants at low salinity. Equable salt tolerance among the three species up to 1200mM NaCl means that other factors are likely to contribute to species composition at sites with salinities below this level. The lower NaCl tolerance threshold for survival in T. indica suggests that this species would be competitively inferior to T. medusa and T. auriculata in extremely saline soils.

    U2 - 10.1071/FP16025

    DO - 10.1071/FP16025

    M3 - Article

    VL - 43

    SP - 739

    EP - 750

    JO - Functional Plant Biology

    JF - Functional Plant Biology

    SN - 1445-4408

    IS - 8

    ER -