title: Hexanoic acid-induced resistance against Botrytis cinerea in tomato plants.
abstract: We have demonstrated that root treatment with hexanoic acid protects tomato plants against Botrytis cinerea. Hexanoic acid-induced resistance (Hx-IR) was blocked in the jasmonic acid (JA)-insensitive mutant jai1 (a coi1 homolog) and in the abscisic acid (ABA)-deficient mutant flacca (flc). Upon infection, the LoxD gene as well as the oxylipin 12-oxo-phytodienoic acid and the bioactive molecule JA-Ile were clearly induced in treated plants. However, the basal ABA levels were not altered. Hexanoic acid primed callose deposition against B. cinerea in a cultivar-dependent manner. Treated plants from Ailsa Craig, Moneymaker, and Rheinlands Ruhm showed increased callose deposition but not from Castlemart. Hexanoic acid did not prime callose accumulation in flc plants upon B. cinerea infection; therefore, ABA could act as a positive regulator of Hx-IR by enhancing callose deposition. Furthermore, although hexanoic acid protected the JA-deficient mutant defensless1 (def1), the priming for callose was higher than in the wild type. This suggests a link between JA and callose deposition in tomato. Hence, the obtained results support the idea that callose, oxylipins, and the JA-signaling pathway are involved in Hx-IR against B. cinerea. Moreover our data support the relevance of JA-signaling for basal defense against this necrotroph in tomato. Hexanoic acid also protected against Pseudomonas syringae, indicating a broad-spectrum effect for this new inducer.
authors.affiliation: Laboratorio de Bioquímica y Biotecnología, Area de Fisiología Vegetal, Departamento de Ciencias Agrarias y del Medio Natural, ESTCE, Universitat Jaume I, 12071, Castellón, Spain.
authors.forename: Begonya
authors.initials: B
authors.lastname: Vicedo
authors.forename: Víctor
authors.initials: V
authors.lastname: Flors
authors.forename: María
authors.initials: M
authors.lastname: de la O Leyva
authors.forename: Ivan
authors.initials: I
authors.lastname: Finiti
authors.forename: Zhana
authors.initials: Z
authors.lastname: Kravchuk
authors.forename: María Dolores
authors.initials: MD
authors.lastname: Real
authors.forename: Pilar
authors.initials: P
authors.lastname: García-Agustín
authors.forename: Carmen
authors.initials: C
authors.lastname: González-Bosch
mesh_terms: D000040:Abscisic Acid; D020171:Botrytis / Q000502:physiology*; D002208:Caproates / Q000494:pharmacology*; D018551:Solanum lycopersicum / Q000382:microbiology*; D009154:Mutation; D010935:Plant Diseases / Q000382:microbiology*; D044224:Pseudomonas syringae; D015398:Signal Transduction
chemical_list: D002208:Caproates; C037652:hexanoic acid; D000040:Abscisic Acid