title: Chemical root to shoot signaling under drought.
abstract: Chemical signals are important for plant adaptation to water stress. As soils become dry, root-sourced signals are transported via the xylem to leaves and result in reduced water loss and decreased leaf growth. The presence of chemical signals in xylem sap is accepted, but the identity of these signals is controversial. Abscisic acid (ABA), pH, cytokinins, a precursor of ethylene, malate and other unidentified factors have all been implicated in root to shoot signaling under drought. This review describes current knowledge of, and advances in, research on chemical signals that are sent from roots under drought. The contribution of these different potential signals is discussed within the context of their role in stress signaling.
authors.affiliation: Donald Danforth Plant Science Center, 975N. Warson Rd, St. Louis, MO 63132, USA. dschachtman@danforthcenter.org
authors.forename: Daniel P
authors.initials: DP
authors.lastname: Schachtman
authors.forename: Jason Q D
authors.initials: JQ
authors.lastname: Goodger
mesh_terms: D000040:Abscisic Acid / Q000378:metabolism*; D000383:Agriculture / Q000379:methods; D003583:Cytokinins / Q000378:metabolism*; D055864:Droughts; D006863:Hydrogen-Ion Concentration; D018517:Plant Roots / Q000378:metabolism*; D018520:Plant Shoots / Q000378:metabolism*; D054046:Plant Stomata / Q000502:physiology; D015398:Signal Transduction; D013312:Stress, Physiological; D014867:Water / Q000378:metabolism; D052584:Xylem / Q000378:metabolism
chemical_list: D003583:Cytokinins; D014867:Water; D000040:Abscisic Acid