Lancaster EPrints

Root-to-shoot signalling when soil moisture is heterogeneous: increasing the proportion of root biomass in drying soil inhibits leaf growth and increases leaf abscisic acid concentration

Martin-Vertedor, Ana Isabel and Dodd, Ian C. (2011) Root-to-shoot signalling when soil moisture is heterogeneous: increasing the proportion of root biomass in drying soil inhibits leaf growth and increases leaf abscisic acid concentration. Plant, Cell and Environment, 34 (7). pp. 1164-1175. ISSN 0140-7791

[img] Microsoft Word - Draft Version
Download (119Kb)

    Abstract

    To determine whether root-to-shoot signalling of soil moisture heterogeneity depended on root distribution, wild-type (WT) and abscisic acid (ABA)-deficient (Az34) barley (Hordeum vulgare) plants were grown in split pots into which different numbers of seminal roots were inserted. After establishment, all plants received the same irrigation volumes, with one pot watered (w) and the other allowed to dry the soil (d), imposing three treatments (1 d : 3 w, 2 d : 2 w, 3 d : 1 w) that differed in the number of seminal roots exposed to drying soil. Root distribution did not affect leaf water relations and had no sustained effect on plant evapotranspiration (ET). In both genotypes, leaf elongation was less and leaf ABA concentrations were higher in plants with more roots in drying soil, with leaf ABA concentrations and water potentials 30% and 0.2 MPa higher, respectively, in WT plants. Whole-pot soil drying increased xylem ABA concentrations, but maximum values obtained when leaf growth had virtually ceased (100 nM in Az34, 330 nM in WT) had minimal effects (<40% leaf growth inhibition) when xylem supplied to detached shoots. Although ABA may not regulate leaf growth in vivo, genetic variation in foliar ABA concentration in the field may indicate different root distributions between upper (drier) and lower (wetter) soil layers.

    Item Type: Article
    Journal or Publication Title: Plant, Cell and Environment
    Uncontrolled Keywords: Hordeum vulgare ; ABA ; chemical signals ; leaf elongation ; mutant ; partial root zone drying ; root distribution ; soil moisture heterogeneity ; split pot
    Subjects: G Geography. Anthropology. Recreation > GE Environmental Sciences
    Departments: Faculty of Science and Technology > Lancaster Environment Centre
    ID Code: 49438
    Deposited By: ep_importer_pure
    Deposited On: 05 Aug 2011 16:59
    Refereed?: Yes
    Published?: Published
    Last Modified: 17 Sep 2013 08:26
    Identification Number:
    URI: http://eprints.lancs.ac.uk/id/eprint/49438

    Actions (login required)

    View Item