title: Burkholderia phytofirmans PsJN acclimates grapevine to cold by modulating carbohydrate metabolism.
abstract: Low temperatures damage many temperate crops, including grapevine, which, when exposed to chilling, can be affected by symptoms ranging from reduced yield up to complete infertility. We have previously demonstrated that Burkholderia phytofirmans PsJN, a plant growth-promoting rhizobacteria (PGPR) that colonizes grapevine, is able to reduce chilling-induced damage. We hypothesized that the induced tolerance may be explained at least partly by the impact of bacteria on grapevine photosynthesis or carbohydrate metabolism during cold acclimation. To investigate this hypothesis, we monitored herein the fluctuations of photosynthesis parameters (net photosynthesis [P(n)], intercellular CO(2) concentration, stomatal conductances, ΦPSII, and total chlorophyll concentration), starch, soluble sugars (glucose, fructose, saccharose, mannose, raffinose, and maltose), and their precursors during 5 days of chilling exposure (4°C) on grapevine plantlets. Bacterization affects photosynthesis in a non-stomatal dependent pattern and reduced long-term impact of chilling on P(n). Furthermore, all studied carbohydrates known to be involved in cold stress tolerance accumulate in non-chilled bacterized plantlets, although some of them remained more concentrated in the latter after chilling exposure. Overall, our results suggest that modification of carbohydrate metabolism in bacterized grapevine plantlets may be one of the major effects by which this PGPR reduces chilling-induced damage.
authors.affiliation: Université de Reims Champagne Ardenne, Unité de Recherche Vignes et Vins de Champagne–Stress et Environnement (EA 2069), UFR Sciences Exactes et Naturelles, BP 1039, 51687 Reims Cedex 2, France.
authors.forename: Olivier
authors.initials: O
authors.lastname: Fernandez
authors.forename: Andreas
authors.initials: A
authors.lastname: Theocharis
authors.forename: Sophie
authors.initials: S
authors.lastname: Bordiec
authors.forename: Regina
authors.initials: R
authors.lastname: Feil
authors.forename: Lucile
authors.initials: L
authors.lastname: Jacquens
authors.forename: Christophe
authors.initials: C
authors.lastname: Clément
authors.forename: Florence
authors.initials: F
authors.lastname: Fontaine
authors.forename: Essaid Ait
authors.initials: EA
authors.lastname: Barka
mesh_terms: D000222:Adaptation, Physiological / Q000502:physiology*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D019117:Burkholderia / Q000235:genetics / Q000378:metabolism*; D002241:Carbohydrates / Q000502:physiology; D003080:Cold Temperature; D015964:Gene Expression Regulation, Bacterial / Q000502:physiology; D006019:Glycolysis / Q000502:physiology; D010788:Photosynthesis / Q000502:physiology; D010860:Pigments, Biological / Q000378:metabolism; D013213:Starch / Q000378:metabolism; D020950:Vitex / Q000382:microbiology* / Q000502:physiology*
chemical_list: D001426:Bacterial Proteins; D002241:Carbohydrates; D010860:Pigments, Biological; D013213:Starch