Host Plant Specific Control of 2,4-Diacetylphloroglucinol Production in the Rhizosphere

Agronomy

Feth el Zahar Haichar¹  Sylvain Fochesato² 

[1] Université Lyon1, CNRS, UMR5557, INRA, USC1364, Ecologie Microbienne, Groupes Fonctionnels Microbiens et Cycle de l’Azote, Villeurbanne F-69622, France; E-Mail:;CEA, DSV, IBEB, SBVME, Lab Ecol Microb Rhizosphere & Environ Extrem (LEMiRE), Saint-Paul-lez-Durance, France; E-Mail:

关键词: Pseudomonas brassicacearum;    phlD;    2;    4-diacetylphloroglucinol;    biocontrol;    rhizosphere;    root exudates;    mRNA-SIP;    DNA-SIP.;   

DOI  :  10.3390/agronomy3040621

来源: mdpi

【 摘 要 】

To shed light on phytobeneficial bacterial gene expression in situ, we investigated the expression of phlD gene involved in 2,4-diacetylphloroglucinol production. For that purpose, stable isotope probing (SIP) of DNA and mRNA approaches were used. Arabidopsis thaliana seedlings were grown under ¹³CO₂ for 27 days, and the presence and expression of phlD gene was determined in the rhizosphere soil and on the roots of A. thaliana. Results showed that phlD was present and expressed by bacteria inhabiting rhizosphere soil and deriving nutrients from the breakdown of organic matter and from root exudates, whereas phlD gene expression seemed to be repressed on roots. These data were validated in vitro by inoculating four plant species by the phytobeneficial bacterium Pseudomonas brassicacearum. phlD gene expression was highly activated by root exudates of wheat and that of Medicago truncatula and to a lesser extent by that of Brassica napus while it was completely suppressed by root exudates of A. thaliana. Overall, these results lead us to the conclusion that the signals to down regulate phl gene expression may derive from A. thaliana root exudates.

【 授权许可】

CC BY   
© 2013 by the authors; licensee MDPI, Basel, Switzerland.