Priming for JA-dependent defenses using hexanoic acid is an effective mechanism to protect Arabidopsis against B. cinerea.
Soil drench treatments with hexanoic acid can effectively protect Arabidopsis plants against Botrytis cinerea through a mechanism based on a stronger and faster accumulation of JA-dependent defenses. Plants impaired in ethylene, salicylic acid, abscisic acid or glutathion pathways showed intact protection by hexanoic acid upon B. cinerea infection. Accordingly, no significant changes in the SA marker gene PR-1 in either the SA or ABA hormone balance were observed in the infected and treated plants. In contrast, the JA signaling pathway showed dramatic changes after hexanoic acid treatment, mainly when the pathogen was present. The impaired JA mutants, jin1-2 and jar1, were unable to display hexanoic acid priming against the necrotroph. In addition, hexanoic acid-treated plants infected with B. cinerea showed priming in the expression of the PDF1.2, PR-4 and VSP1 genes implicated in the JA pathways. Moreover, JA and OPDA levels were primed at early stages by hexanoic acid. Treatments also stimulated increased callose accumulation in response to the pathogen. Although callose accumulation has proved an effective IR mechanism against B. cinerea, it is apparently not essential to express hexanoic acid-induced resistance (HxAc-IR) because the mutant pmr4.1 (callose synthesis defective mutant) is protected by treatment. We recently described how hexanoic acid treatments can protect tomato plants against B. cinerea by stimulating ABA-dependent callose deposition and by priming OPDA and JA-Ile production. We clearly demonstrate here that Hx-IR is a dependent plant species, since this acid protects Arabidopsis plants against the same necrotroph by priming JA-dependent defenses without enhancing callose accumulation.
Laboratorio de Bioquímica y Biotecnología, Área de Fisiología Vegetal, Departamento de Ciencias Agrarias y del Medio Natural, ESTCE, Universitat Jaume I, Campus de Riu Sec., Castellón, Spain.
Zhana
Z
Kravchuk
Begonya
B
Vicedo
Víctor
V
Flors
Gemma
G
Camañes
Carmen
C
González-Bosch
Pilar
P
García-Agustín
D000040:Abscisic Acid / Q000378:metabolism / Q000494:pharmacology; D000528:Alternaria / Q000472:pathogenicity; D000890:Anti-Infective Agents; D017360:Arabidopsis / Q000187:drug effects* / Q000235:genetics* / Q000382:microbiology / Q000502:physiology; D029681:Arabidopsis Proteins / Q000235:genetics; D020171:Botrytis / Q000472:pathogenicity*; D002208:Caproates / Q000494:pharmacology*; D003517:Cyclopentanes / Q000378:metabolism* / Q000494:pharmacology; D023082:Defensins / Q000235:genetics; D010450:Endopeptidases / Q000235:genetics; D005030:Ethylenes / Q000378:metabolism / Q000494:pharmacology; D018506:Gene Expression Regulation, Plant; D005936:Glucans / Q000378:metabolism; D005978:Glutathione / Q000378:metabolism; D009154:Mutation; D054883:Oxylipins / Q000378:metabolism* / Q000494:pharmacology; D010935:Plant Diseases / Q000235:genetics / Q000382:microbiology; D010937:Plant Growth Regulators / Q000378:metabolism / Q000494:pharmacology; D057865:Plant Immunity / Q000187:drug effects / Q000235:genetics; D018515:Plant Leaves / Q000382:microbiology; D010940:Plant Proteins / Q000235:genetics; D030821:Plants, Genetically Modified; D020156:Salicylic Acid / Q000378:metabolism / Q000494:pharmacology; D015398:Signal Transduction
D000040:Abscisic Acid; D000890:Anti-Infective Agents; D029681:Arabidopsis Proteins; D002208:Caproates; D003517:Cyclopentanes; D023082:Defensins; D010450:Endopeptidases; D005030:Ethylenes; D005936:Glucans; D005978:Glutathione; D054883:Oxylipins; D010937:Plant Growth Regulators; D010940:Plant Proteins; D020156:Salicylic Acid; C487542:At5g44420 protein, Arabidopsis; C053376:pathogenesis-related proteins, plant; C037652:hexanoic acid; C011006:jasmonic acid; C048306:callose; C036216:ethylene; C441479:VSP1 protein, Arabidopsis