title: How does a little stress stimulate a plant?
abstract: In contrast to the damaging effect of high-concentration chemical stressors, the same agents in very low (submicromolar) concentrations have a positive effect on the treated plants, which is non-specific (independent of the chemical nature of the agent). The direct responses depend on the treated organ. When leaves are treated, the effects include an increase in chlorophyll content, CO(2) fixation and delaying senescence of chloroplasts. When roots are treated, the direct effect is an increased cytokinin synthesis. This hormone, after being transported to the shoot, exerts secondary effects, which are similar to the primary ones in leaves. The signalization routes involved in the primary effects proved to be the phosphoinositide and MAPK pathways in any stimulated organ. In this mini-review we summarize our current knowledge about the effects of low-concentration stressors and their mechanism of action with the help of the four used model systems: detached non-rooting and rooting leaves, hydroponically treated and sprayed seedlings.
authors.affiliation: Department of Plant Physiology and Molecular Plant Biology, Eötvös Loránd University, Budapest, Hungary. k-erika@elte.hu
authors.forename: Erika
authors.initials: E
authors.lastname: Kovács-Bogdán
authors.forename: Péter
authors.initials: P
authors.lastname: Nyitrai
authors.forename: Aron
authors.initials: A
authors.lastname: Keresztes
mesh_terms: D002734:Chlorophyll / Q000032:analysis; D003583:Cytokinins / Q000096:biosynthesis; D020935:MAP Kinase Signaling System; D010716:Phosphatidylinositols / Q000378:metabolism; D063245:Plant Development; D018515:Plant Leaves / Q000187:drug effects; D018517:Plant Roots / Q000187:drug effects; D010944:Plants / Q000187:drug effects* / Q000378:metabolism*; D015398:Signal Transduction; D013312:Stress, Physiological
chemical_list: D003583:Cytokinins; D010716:Phosphatidylinositols; D002734:Chlorophyll