title: An ethoxylated surfactant enhances the penetration of the sulfated laminarin through leaf cuticle and stomata, leading to increased induced resistance against grapevine downy mildew.
abstract: Some β-1,3-glucans and particularly sulfated laminarin (PS3) are known as resistance inducers (RIs) in grapevine against the downy mildew. However, their efficacy in vineyard is still often too low, which might be caused by a limited penetration through the leaf cuticle following spray application. We used (14) C-sucrose uptake experiments with grapevine leaves in order to select a surfactant as saccharide penetration enhancer. Our results showed that although sucrose foliar uptake was low, it was strongly enhanced by Dehscofix CO125 (DE), a highly ethoxylated surfactant. Fluorescent saccharides were then produced and laser scanning microscopy was used to analyze their foliar diffusion pattern in Arabidopsis thaliana and grapevine. Interestingly, sucrose and PS3 were seemingly able to penetrate the leaf cuticle only when formulated with DE. Diffusion could preferentially occur via stomata, anticlinal cell walls and trichomes. In grapevine, PS3 penetration rate was much higher on the stomateous abaxial surface of the leaf than on the adaxial surface. Finally, using DE allowed a higher level of downy mildew control by PS3, which corroborated diffusion observations. Our results have practical consequences for the improvement of treatments with saccharidic inducers on grape. That is, formulation of such RIs plays a critical role for their cuticular diffusion and consequently their efficacy. Also, spray application should preferentially target the abaxial surface of the leaves in order to maximize their penetration.
authors.affiliation: Ecole Nationale Supérieure de Chimie de Rennes, CNRS, UMR 6226, Rennes, France.|Université européenne de Bretagne, Rennes, France.|INRA, UMR 1347 Agroécologie, ERL CNRS 6300, Dijon, France.
authors.forename: Franck
authors.initials: F
authors.lastname: Paris
authors.affiliation: INRA, UMR 1347 Agroécologie, ERL CNRS 6300, Dijon, France.
authors.forename: Yuko
authors.initials: Y
authors.lastname: Krzyżaniak
authors.affiliation: INRA, UMR 1347 Agroécologie, ERL CNRS 6300, Dijon, France.
authors.forename: Christian
authors.initials: C
authors.lastname: Gauvrit
authors.affiliation: Laboratoires Goëmar, S.A.S.-Parc technopolitain Atalante, Saint-Malo, France.
authors.forename: Frank
authors.initials: F
authors.lastname: Jamois
authors.affiliation: Université de Bordeaux, Laboratoire de Biogenèse Membranaire, UMR 5200, Bordeaux, France.|CNRS, UMR 5200, Laboratoire de Biogenèse Membranaire, Bordeaux, France.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Domergue
authors.affiliation: Université de Bordeaux, Laboratoire de Biogenèse Membranaire, UMR 5200, Bordeaux, France.|CNRS, UMR 5200, Laboratoire de Biogenèse Membranaire, Bordeaux, France.
authors.forename: Jérôme
authors.initials: J
authors.lastname: Joubès
authors.affiliation: Ecole Nationale Supérieure de Chimie de Rennes, CNRS, UMR 6226, Rennes, France.|Université européenne de Bretagne, Rennes, France.
authors.forename: Vincent
authors.initials: V
authors.lastname: Ferrières
authors.affiliation: Université de Bourgogne, UMR 1347 Agroécologie, ERL CNRS 6300, Dijon, France.
authors.forename: Marielle
authors.initials: M
authors.lastname: Adrian
authors.affiliation: Ecole Nationale Supérieure de Chimie de Rennes, CNRS, UMR 6226, Rennes, France.|Université européenne de Bretagne, Rennes, France.
authors.forename: Laurent
authors.initials: L
authors.lastname: Legentil
authors.affiliation: INRA, UMR 1347 Agroécologie, ERL CNRS 6300, Dijon, France.
authors.forename: Xavier
authors.initials: X
authors.lastname: Daire
authors.affiliation: Université de Bourgogne, UMR 1347 Agroécologie, ERL CNRS 6300, Dijon, France.
authors.forename: Sophie
authors.initials: S
authors.lastname: Trouvelot
mesh_terms: D002250:Carbon Radioisotopes; D002784:Cholesterol / Q000378:metabolism; D004058:Diffusion; D004187:Disaccharides / Q000494:pharmacology; D060467:Disease Resistance / Q000187:drug effects*; D005027:Ethylene Oxide / Q000737:chemistry*; D005453:Fluorescence; D007700:Kinetics; D009868:Oomycetes / Q000187:drug effects*; D010935:Plant Diseases / Q000382:microbiology*; D054046:Plant Stomata / Q000033:anatomy & histology / Q000187:drug effects / Q000502:physiology* / Q000648:ultrastructure; D011134:Polysaccharides / Q000737:chemistry / Q000494:pharmacology*; D013395:Sucrose / Q000378:metabolism; D013501:Surface-Active Agents / Q000494:pharmacology*; D027843:Vitis / Q000187:drug effects / Q000382:microbiology*; D014885:Waxes / Q000378:metabolism
chemical_list: D002250:Carbon Radioisotopes; D004187:Disaccharides; D011134:Polysaccharides; D013501:Surface-Active Agents; D014885:Waxes; D013395:Sucrose; C029454:turanose; C053460:laminarin sulfate; D002784:Cholesterol; D005027:Ethylene Oxide