title: Growth biostimulation of quorum-quenching bacteria by gammagamma-heptalactone treatment in the hydroponic rhizosphere of Solanum tuberosum.
abstract: Several bacterial plant pathogens, including Pectobacterium, use a cell-to-cell communication system called quorum sensing (QS) to synchronize and regulate expression of the virulence factors. In this study, the biomolecule gamma-heptalactone (GHL) was introduced in hydroponic culture of Solanum tuberosum to stimulate growth of the native rhizospheric bacteria which are able to degrade the QS signal, hence potentially quench the QS-regulated virulence of Pectobacterium. During two annual campaigns, GHL-treatment efficiently stimulated the growth of QS-degrading bacterial population of Rhodococcus erythropolis in the rhizosphere of potato plants. Analytical chemistry showed that GHL rapidly disappeared because it could be assimilated as a carbon source by R. erythropolis. Moreover, pyrosequencing of the rrs-amplicons revealed a strong modification of the structure and diversity of bacterial populations, when GHL-treated and untreated conditions were compared. This work highlighted a potential innovative strategy for stimulating the growth and root colonization of QS-degrading bacteria, which would act as biocontrol agents against plant QS-pathogens.
authors.affiliation: Centre National de la Recherche Scientifique, Institut des Sciences du Végétal, UPR 2355, FR-91198 Gif-sur-Yvette, France.
authors.forename: M
authors.initials: M
authors.lastname: Tannieres
authors.forename: A
authors.initials: A
authors.lastname: Beury-Cirou
authors.forename: D
authors.initials: D
authors.lastname: Faure
mesh_terms: D001419:Bacteria / Q000145:classification / Q000187:drug effects*; D018527:Hydroponics; D007783:Lactones / Q000737:chemistry / Q000494:pharmacology*; D015394:Molecular Structure; D018517:Plant Roots / Q000382:microbiology*; D053038:Quorum Sensing; D011198:Solanum tuberosum / Q000382:microbiology*; D013997:Time Factors
chemical_list: D007783:Lactones