title: Priming of wheat with the green leaf volatile Z-3-hexenyl acetate enhances defense against Fusarium graminearum but boosts deoxynivalenol production.
abstract: Priming refers to a mechanism whereby plants are sensitized to respond faster and/or more strongly to future pathogen attack. Here, we demonstrate that preexposure to the green leaf volatile Z-3-hexenyl acetate (Z-3-HAC) primed wheat (Triticum aestivum) for enhanced defense against subsequent infection with the hemibiotrophic fungus Fusarium graminearum. Bioassays showed that, after priming with Z-3-HAC, wheat ears accumulated up to 40% fewer necrotic spikelets. Furthermore, leaves of seedlings showed significantly smaller necrotic lesions compared with nonprimed plants, coinciding with strongly reduced fungal growth in planta. Additionally, we found that F. graminearum produced more deoxynivalenol, a mycotoxin, in the primed treatment. Expression analysis of salicylic acid (SA) and jasmonic acid (JA) biosynthesis genes and exogenous methyl salicylate and methyl jasmonate applications showed that plant defense against F. graminearum is sequentially regulated by SA and JA during the early and later stages of infection, respectively. Interestingly, analysis of the effect of Z-3-HAC pretreatment on SA- and JA-responsive gene expression in hormone-treated and pathogen-inoculated seedlings revealed that Z-3-HAC boosts JA-dependent defenses during the necrotrophic infection stage of F. graminearum but suppresses SA-regulated defense during its biotrophic phase. Together, these findings highlight the importance of temporally separated hormone changes in molding plant health and disease and support a scenario whereby the green leaf volatile Z-3-HAC protects wheat against Fusarium head blight by priming for enhanced JA-dependent defenses during the necrotrophic stages of infection.
authors.affiliation: Laboratory of Agrozoology, Department of Crop Protection (M.A., N.D.Z., G.S.), Department of Applied Biosciences (M.A., K.A., N.D.Z., G.H.), Laboratory of Plant Ecology (K.S.), and Laboratory of Phytopathology, Department of Crop Protection (D.D.V.), Faculty of Bioscience Engineering, Ghent University, B-9000 Ghent, Belgium; andLaboratory of Chemical Analysis, Department of Veterinary Public Health and Food Safety, Faculty of Veterinary Medicine, Ghent University, B-9820 Merelbeke, Belgium (L.V.M., L.V.) maarten.ameye@ugent.be guy.smagghe@ugent.be.
authors.forename: Maarten
authors.initials: M
authors.lastname: Ameye
authors.affiliation: Laboratory of Agrozoology, Department of Crop Protection (M.A., N.D.Z., G.S.), Department of Applied Biosciences (M.A., K.A., N.D.Z., G.H.), Laboratory of Plant Ecology (K.S.), and Laboratory of Phytopathology, Department of Crop Protection (D.D.V.), Faculty of Bioscience Engineering, Ghent University, B-9000 Ghent, Belgium; andLaboratory of Chemical Analysis, Department of Veterinary Public Health and Food Safety, Faculty of Veterinary Medicine, Ghent University, B-9820 Merelbeke, Belgium (L.V.M., L.V.).
authors.forename: Kris
authors.initials: K
authors.lastname: Audenaert
authors.affiliation: Laboratory of Agrozoology, Department of Crop Protection (M.A., N.D.Z., G.S.), Department of Applied Biosciences (M.A., K.A., N.D.Z., G.H.), Laboratory of Plant Ecology (K.S.), and Laboratory of Phytopathology, Department of Crop Protection (D.D.V.), Faculty of Bioscience Engineering, Ghent University, B-9000 Ghent, Belgium; andLaboratory of Chemical Analysis, Department of Veterinary Public Health and Food Safety, Faculty of Veterinary Medicine, Ghent University, B-9820 Merelbeke, Belgium (L.V.M., L.V.).
authors.forename: Nathalie
authors.initials: N
authors.lastname: De Zutter
authors.affiliation: Laboratory of Agrozoology, Department of Crop Protection (M.A., N.D.Z., G.S.), Department of Applied Biosciences (M.A., K.A., N.D.Z., G.H.), Laboratory of Plant Ecology (K.S.), and Laboratory of Phytopathology, Department of Crop Protection (D.D.V.), Faculty of Bioscience Engineering, Ghent University, B-9000 Ghent, Belgium; andLaboratory of Chemical Analysis, Department of Veterinary Public Health and Food Safety, Faculty of Veterinary Medicine, Ghent University, B-9820 Merelbeke, Belgium (L.V.M., L.V.).
authors.forename: Kathy
authors.initials: K
authors.lastname: Steppe
authors.affiliation: Laboratory of Agrozoology, Department of Crop Protection (M.A., N.D.Z., G.S.), Department of Applied Biosciences (M.A., K.A., N.D.Z., G.H.), Laboratory of Plant Ecology (K.S.), and Laboratory of Phytopathology, Department of Crop Protection (D.D.V.), Faculty of Bioscience Engineering, Ghent University, B-9000 Ghent, Belgium; andLaboratory of Chemical Analysis, Department of Veterinary Public Health and Food Safety, Faculty of Veterinary Medicine, Ghent University, B-9820 Merelbeke, Belgium (L.V.M., L.V.).
authors.forename: Lieven
authors.initials: L
authors.lastname: Van Meulebroek
authors.affiliation: Laboratory of Agrozoology, Department of Crop Protection (M.A., N.D.Z., G.S.), Department of Applied Biosciences (M.A., K.A., N.D.Z., G.H.), Laboratory of Plant Ecology (K.S.), and Laboratory of Phytopathology, Department of Crop Protection (D.D.V.), Faculty of Bioscience Engineering, Ghent University, B-9000 Ghent, Belgium; andLaboratory of Chemical Analysis, Department of Veterinary Public Health and Food Safety, Faculty of Veterinary Medicine, Ghent University, B-9820 Merelbeke, Belgium (L.V.M., L.V.).
authors.forename: Lynn
authors.initials: L
authors.lastname: Vanhaecke
authors.affiliation: Laboratory of Agrozoology, Department of Crop Protection (M.A., N.D.Z., G.S.), Department of Applied Biosciences (M.A., K.A., N.D.Z., G.H.), Laboratory of Plant Ecology (K.S.), and Laboratory of Phytopathology, Department of Crop Protection (D.D.V.), Faculty of Bioscience Engineering, Ghent University, B-9000 Ghent, Belgium; andLaboratory of Chemical Analysis, Department of Veterinary Public Health and Food Safety, Faculty of Veterinary Medicine, Ghent University, B-9820 Merelbeke, Belgium (L.V.M., L.V.).
authors.forename: David
authors.initials: D
authors.lastname: De Vleesschauwer
authors.affiliation: Laboratory of Agrozoology, Department of Crop Protection (M.A., N.D.Z., G.S.), Department of Applied Biosciences (M.A., K.A., N.D.Z., G.H.), Laboratory of Plant Ecology (K.S.), and Laboratory of Phytopathology, Department of Crop Protection (D.D.V.), Faculty of Bioscience Engineering, Ghent University, B-9000 Ghent, Belgium; andLaboratory of Chemical Analysis, Department of Veterinary Public Health and Food Safety, Faculty of Veterinary Medicine, Ghent University, B-9820 Merelbeke, Belgium (L.V.M., L.V.).
authors.forename: Geert
authors.initials: G
authors.lastname: Haesaert
authors.affiliation: Laboratory of Agrozoology, Department of Crop Protection (M.A., N.D.Z., G.S.), Department of Applied Biosciences (M.A., K.A., N.D.Z., G.H.), Laboratory of Plant Ecology (K.S.), and Laboratory of Phytopathology, Department of Crop Protection (D.D.V.), Faculty of Bioscience Engineering, Ghent University, B-9000 Ghent, Belgium; andLaboratory of Chemical Analysis, Department of Veterinary Public Health and Food Safety, Faculty of Veterinary Medicine, Ghent University, B-9820 Merelbeke, Belgium (L.V.M., L.V.) maarten.ameye@ugent.be guy.smagghe@ugent.be.
authors.forename: Guy
authors.initials: G
authors.lastname: Smagghe
mesh_terms: D000085:Acetates / Q000378:metabolism / Q000494:pharmacology*; D003517:Cyclopentanes / Q000378:metabolism; D005670:Fusarium / Q000378:metabolism* / Q000472:pathogenicity; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D054883:Oxylipins / Q000378:metabolism; D010935:Plant Diseases / Q000276:immunology* / Q000382:microbiology; D010937:Plant Growth Regulators / Q000378:metabolism; D057865:Plant Immunity / Q000187:drug effects*; D018515:Plant Leaves / Q000187:drug effects / Q000235:genetics / Q000276:immunology; D010940:Plant Proteins / Q000235:genetics; D020156:Salicylic Acid / Q000378:metabolism; D036226:Seedlings / Q000187:drug effects / Q000235:genetics / Q000276:immunology; D014255:Trichothecenes / Q000032:analysis / Q000378:metabolism*; D014908:Triticum / Q000187:drug effects* / Q000235:genetics / Q000276:immunology
chemical_list: D000085:Acetates; D003517:Cyclopentanes; D054883:Oxylipins; D010937:Plant Growth Regulators; D010940:Plant Proteins; D014255:Trichothecenes; C425828:3-hexenylacetate; C072239:methyl jasmonate; C007262:deoxynivalenol; D020156:Salicylic Acid