Salt stress responses in salt-sensitive Arabidopsis thaliana (2-150mM NaCl) and the closely related salt-tolerant Thellungiella salsuginea (Eutrema halophila, 150-350mM NaCl) were compared to identify hormonal and transcriptomic changes associated with enhanced stress tolerance. Phytohormone levels, expression of selected genes, membrane stability, and Na+ and K+ concentrations were measured in shoot apices, leaves, and roots. Thellungiella exhibited higher salt stress tolerance associated with elevated basal levels of abscisic acid and jasmonic acid, and lower levels of active cytokinins (excluding cis-zeatin) in shoot apices. Analysis of the dynamics of the early salt stress response (15min to 24h) revealed that the halophyte response was faster and stronger. Very mild stress, in our hydropony arrangement 2-25mM NaCl, affected the transcription of genes involved in cytokinin metabolism (AtIPTs, AtCKXs). Mild stress induced in Arabidopsis (50mM) stress responses only in shoot apices, while in Thellungiella (150mM) across the whole plant. Arabidopsis exhibited in hydropony evidence of severe stress above 75mM NaCl and died in 150mM, whereas the halophyte only became severely stressed above 225mM. The responses of individual phytohormones (cytokinins, auxin, abscisic acid, jasmonic acid, salicylic acid and their metabolites) to salinity are discussed.

Laboratory of Hormonal Regulations in Plants Institute of Experimental Botany AS CR Rozvojova 263 165 02 Prague 6 Czech Republic

Laboratory of Hormonal Regulations in Plants Institute of Experimental Botany AS CR Rozvojova 263 165 02 Prague 6 Czech Republic; Department of Experimental Plant Biology Faculty of Science Charles University Vinicna 5 128 44 Prague 2 Czech Republic

Laboratory of Plant Biotechnologies Institute of Experimental Botany AS CR Rozvojova 263 165 02 Prague 6 Czech Republic

Citace poskytuje Crossref.org

Salt-Specific Gene Expression Reveals Elevated Auxin Levels in Arabidopsis thaliana Plants Grown Under Saline Conditions

Phytohormone profiles in non-transformed and AtCKX transgenic centaury (Centaurium erythraea Rafn) shoots and roots in response to salinity stress in vitro

Heat Stress Targeting Individual Organs Reveals the Central Role of Roots and Crowns in Rice Stress Responses

Heat Acclimation and Inhibition of Cytokinin Degradation Positively Affect Heat Stress Tolerance of Arabidopsis

Fast Regulation of Hormone Metabolism Contributes to Salt Tolerance in Rice (Oryzasativa spp. Japonica, L.) by Inducing Specific Morpho-Physiological Responses

Salt and oxidative stresses uniquely regulate tomato cytokinin levels and transcriptomic response