Title: | Role of the GacS Sensor Kinase in the Regulation of Volatile Production by Plant Growth-Promoting Pseudomonas fluorescens SBW25 |
Author(s): | Cheng X; Cordovez V; Etalo DW; van der Voort M; Raaijmakers JM; |
Address: | "Laboratory of Phytopathology, Wageningen University Wageningen, Netherlands. Department of Microbial Ecology, Netherlands Institute of Ecology Wageningen, Netherlands. Department of Microbial Ecology, Netherlands Institute of EcologyWageningen, Netherlands; Institute of Biology Leiden, Leiden UniversityLeiden, Netherlands" |
ISSN/ISBN: | 1664-462X (Print) 1664-462X (Electronic) 1664-462X (Linking) |
Abstract: | "In plant-associated Pseudomonas species, the production of several secondary metabolites and exoenzymes is regulated by the GacS/GacA two-component regulatory system (the Gac-system). Here, we investigated if a mutation in the GacS sensor kinase affects the production of volatile organic compounds (VOCs) in P. fluorescens SBW25 (Pf.SBW25) and how this impacts on VOCs-mediated growth promotion and induced systemic resistance of Arabidopsis and tobacco. A total of 205 VOCs were detected by Gas Chromatography Mass Spectrometry for Pf. SBW25 and the gacS-mutant grown on two different media for 3 and 6 days. Discriminant function analysis followed by hierarchical clustering revealed 24 VOCs that were significantly different in their abundance between Pf.SBW25 and the gacS-mutant, which included three acyclic alkenes (3-nonene, 4-undecyne, 1-undecene). These alkenes were significantly reduced by the gacS mutation independently of the growth media and of the incubation time. For Arabidopsis, both Pf.SBW25 and the gacS-mutant enhanced, via VOCs, root and shoot biomass, induced systemic resistance against leaf infections by P. syringae and rhizosphere acidification to the same extent. For tobacco, however, VOCs-mediated effects on shoot and root growth were significantly different between Pf.SBW25 and the gacS-mutant. While Pf.SBW25 inhibited tobacco root growth, the gacS-mutant enhanced root biomass and lateral root formation relative to the non-treated control plants. Collectively these results indicate that the sensor kinase GacS is involved in the regulation of VOCs production in Pf.SBW25, affecting plant growth in a plant species-dependent manner" |
Keywords: | Gc-ms Isr Pseudomonas plant growth promotion two-component regulation volatile organic compounds; |
Notes: | "PubMed-not-MEDLINECheng, Xu Cordovez, Viviane Etalo, Desalegn W van der Voort, Menno Raaijmakers, Jos M eng Switzerland 2016/12/06 Front Plant Sci. 2016 Nov 18; 7:1706. doi: 10.3389/fpls.2016.01706. eCollection 2016" |