title: Different forms of osmotic stress evoke qualitatively different responses in rice.
abstract: Drought, salinity and alkalinity are distinct forms of osmotic stress with serious impacts on rice productivity. We investigated, for a salt-sensitive rice cultivar, the response to osmotically equivalent doses of these stresses. Drought, experimentally mimicked by mannitol (single factor: osmotic stress), salinity (two factors: osmotic stress and ion toxicity), and alkalinity (three factors: osmotic stress, ion toxicity, and depletion of nutrients and protons) produced different profiles of adaptive and damage responses, both locally (in the root) as well as systemically (in the shoot). The combination of several stress factors was not necessarily additive, and we even observed cases of mitigation, when two (salinity), or three stressors (alkalinity) were compared to the single stressor (drought). The response to combinations of individual stress factors is therefore not a mere addition of the partial stress responses, but rather represents a new quality of response. We interpret this finding in a model, where the output to signaling molecules is not determined by their abundance per se, but qualitatively depends on their adequate integration into an adaptive signaling network. This output generates a systemic signal that will determine the quality of the shoot response to local concentrations of ions.
authors.affiliation: Botanical Institute, Molecular Cell Biology, Karlsruhe Institute of Technology, Kaiserstr. 2, 76131 Karlsruhe, Germany; Agricultural Genetic Engineering Research Institute (AGERI), Agricultural Research Center (ARC), 9, Gamma st, Giza, 12619, Egypt. Electronic address: yousof_3@hotmail.com.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Hazman
authors.affiliation: Cell and Metabolic Biology, Leibniz Institute of Plant Biochemistry (IPB), Weinberg 3, 06120 Halle (Saale), Germany.
authors.forename: Bettina
authors.initials: B
authors.lastname: Hause
authors.affiliation: Institute of Applied Geosciences, Karlsruhe Institute of Technology (KIT), Adenauerring 20b, 76131 Karlsruhe, Germany.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Eiche
authors.affiliation: Botanical Institute, Molecular Cell Biology, Karlsruhe Institute of Technology, Kaiserstr. 2, 76131 Karlsruhe, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Riemann
authors.affiliation: Botanical Institute, Molecular Cell Biology, Karlsruhe Institute of Technology, Kaiserstr. 2, 76131 Karlsruhe, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Nick
mesh_terms: D000040:Abscisic Acid / Q000378:metabolism; D000468:Alkalies / Q000494:pharmacology; D001692:Biological Transport / Q000187:drug effects; D002247:Carbon Isotopes; D003517:Cyclopentanes / Q000378:metabolism; D055864:Droughts; D005740:Gases / Q000378:metabolism; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D006861:Hydrogen Peroxide / Q000378:metabolism; D015227:Lipid Peroxidation / Q000187:drug effects; D008353:Mannitol / Q000494:pharmacology; D012275:Oryza / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D009997:Osmotic Pressure; D054883:Oxylipins / Q000378:metabolism; D018517:Plant Roots / Q000187:drug effects / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D018520:Plant Shoots / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D054046:Plant Stomata / Q000187:drug effects / Q000502:physiology; D011188:Potassium / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D054712:Salinity; D036226:Seedlings / Q000502:physiology; D012964:Sodium / Q000378:metabolism; D012965:Sodium Chloride / Q000494:pharmacology; D013312:Stress, Physiological / Q000187:drug effects
chemical_list: D000468:Alkalies; D002247:Carbon Isotopes; D003517:Cyclopentanes; D005740:Gases; D054883:Oxylipins; D012333:RNA, Messenger; D008353:Mannitol; D012965:Sodium Chloride; C011006:jasmonic acid; D000040:Abscisic Acid; D012964:Sodium; D006861:Hydrogen Peroxide; D011188:Potassium
keywords: Alkalinity; Jasmonates; Osmotic stress; Rice (Oryza sativa L.); Sodium