title: Enhancement of chilling resistance of inoculated grapevine plantlets with a plant growth-promoting rhizobacterium, Burkholderia phytofirmans strain PsJN.
abstract: In vitro inoculation of Vitis vinifera L. cv. Chardonnay explants with a plant growth-promoting rhizobacterium, Burkholderia phytofirmans strain PsJN, increased grapevine growth and physiological activity at a low temperature. There was a relationship between endophytic bacterial colonization of the grapevine plantlets and their growth at both ambient (26 degrees C) and low (4 degrees C) temperatures and their sensitivities to chilling. The major benefits of bacterization were observed on root growth (11.8- and 10.7-fold increases at 26 degrees C and 4 degrees C, respectively) and plantlet biomass (6- and 2.2-fold increases at 26 degrees C and 4 degrees C, respectively). The inoculation with PsJN also significantly improved plantlet cold tolerance compared to that of the nonbacterized control. In nonchilled plantlets, bacterization enhanced CO(2) fixation and O(2) evolution 1.3 and 2.2 times, respectively. The nonbacterized controls were more sensitive to exposure to low temperatures than were the bacterized plantlets, as indicated by several measured parameters. Moreover, relative to the noninoculated controls, bacterized plantlets had significantly increased levels of starch, proline, and phenolics. These increases correlated with the enhancement of cold tolerance of the grapevine plantlets. In summary, B. phytofirmans strain PsJN inoculation stimulates grapevine growth and improves its ability to withstand cold stress.
authors.affiliation: Laboratoire de Stress, Défenses et Reproduction des Plantes, Unité de Recherche Vignes et Vins de Champagne, UPRES EA 2069, UFR Sciences, Université de Reims Champagne-Ardenne, 51687 Reims Cédex 2, France. ea.barka@univ-reims.fr
authors.forename: Essaid
authors.initials: E
authors.lastname: Ait Barka
authors.forename: Jerzy
authors.initials: J
authors.lastname: Nowak
authors.forename: Christophe
authors.initials: C
authors.lastname: Clément
mesh_terms: D000064:Acclimatization; D019117:Burkholderia / Q000254:growth & development*; D003080:Cold Temperature; D062385:Hydroxybenzoates / Q000378:metabolism; D010788:Photosynthesis; D018515:Plant Leaves / Q000502:physiology; D011392:Proline / Q000378:metabolism; D013213:Starch / Q000378:metabolism; D013696:Temperature; D027843:Vitis / Q000254:growth & development* / Q000382:microbiology* / Q000502:physiology
chemical_list: D062385:Hydroxybenzoates; D013213:Starch; D011392:Proline; C017616:phenolic acid