title: Laminarin elicits defense responses in grapevine and induces protection against Botrytis cinerea and Plasmopara viticola.
abstract: Grapevine (Vitis vinifera L.) is susceptible to many pathogens, such as Botrytis cinerea, Plasmopara viticola, Uncinula necator, and Eutypa lata. Phytochemicals are used intensively in vineyards to limit pathogen infections, but the appearance of pesticide-resistant pathogen strains and a desire to protect the environment require that alternative strategies be found. In the present study, the beta-1,3-glucan laminarin derived from the brown algae Laminaria digitata was shown both to be an efficient elicitor of defense responses in grapevine cells and plants and to effectively reduce B. cinerea and P. viticola development on infected grapevine plants. Defense reactions elicited by laminarin in grapevine cells include calcium influx, alkalinization of the extracellular medium, an oxidative burst, activation of two mitogen-activated protein kinases, expression of 10 defense-related genes with different kinetics and intensities, increases in chitinase and beta-1,3-glucanase activities, and the production of two phytoalexins (resveratrol and epsilon-viniferin). Several of these effects were checked and confirmed in whole plants. Laminarin did not induce cell death. When applied to grapevine plants, laminarin reduced infection by B. cinerea and P. viticola by approximately 55 and 75%, respectively. Our data describing a large set of defense reactions in grapevine indicate that the activation of defense responses using elicitors could be a valuable strategy to protect plants against pathogens.
authors.affiliation: Unité de Recherche Vignes et Vins de Champagne, URVVC-UPRES EA 2069, UFR Sciences, Moulin de la Housse, Université de Reims Champagne-Ardenne, BP 1039, F-51687 Reims cedex 2 France.
authors.forename: Aziz
authors.initials: A
authors.lastname: Aziz
authors.forename: Benoît
authors.initials: B
authors.lastname: Poinssot
authors.forename: Xavier
authors.initials: X
authors.lastname: Daire
authors.forename: Marielle
authors.initials: M
authors.lastname: Adrian
authors.forename: Annie
authors.initials: A
authors.lastname: Bézier
authors.forename: B
authors.initials: B
authors.lastname: Lambert
authors.forename: Jean-Marie
authors.initials: JM
authors.lastname: Joubert
authors.forename: Alain
authors.initials: A
authors.lastname: Pugin
mesh_terms: D001483:Base Sequence; D020171:Botrytis / Q000472:pathogenicity*; D016923:Cell Death / Q000502:physiology; D002688:Chitinases / Q000378:metabolism; D017931:DNA Primers; D018506:Gene Expression Regulation, Plant; D005936:Glucans; D006026:Glycoside Hydrolases / Q000378:metabolism; D009868:Oomycetes / Q000472:pathogenicity*; D010936:Plant Extracts / Q000096:biosynthesis; D011134:Polysaccharides / Q000502:physiology*; D012717:Sesquiterpenes; D015398:Signal Transduction; D013729:Terpenes; D027843:Vitis / Q000235:genetics / Q000382:microbiology* / Q000502:physiology; D000094162:Phytoalexins
chemical_list: D017931:DNA Primers; D005936:Glucans; D010936:Plant Extracts; D011134:Polysaccharides; D012717:Sesquiterpenes; D013729:Terpenes; C008247:laminaran; D006026:Glycoside Hydrolases; D002688:Chitinases; D000094162:Phytoalexins