an identification of the environmental factors regulating the biosynthesis of antibiotics by fluorescent pseudomonads is an essential step toward improving the ability of these bacteria to control plant pathogens. investigation of nine fluorescent pseudomonads, utilized in growth suppression of rhizoctonia solani, the causal agent of root rot and damping-off of bean plants, by the method of hpl...

fluorescent pseudomonads producing 2,4-diacetylphloroglucinol (dapg) antibiotic have been well studied for use as biocontrol agents around the world. pseudomonas fluorescens pgu0 strain was isolated from the rhizosphere of sunflower in bushehr province. dual culture test showed that the strain had antagonistic activity against rhizoctonia solani fungus on different media cultures; moreover, und...

Metabolic co-regulation between biosynthetic pathways for secondary metabolites is common in microbes and can play an important role in microbial interactions. Here, we describe a novel mechanism of metabolic co-regulation in which an intermediate in one pathway is converted into signals that activate a second pathway. Our study focused on the co-regulation of 2,4-diacetylphloroglucinol (DAPG) ...

The effects of Cl(-) on the antibiotics productivity of Pseudomonas sp. YGJ3 were investigated. YGJ3 produced pyoluteorin and 2,4-diacetylphloroglucinol, depending on the concentration of Cl(-) in the culture medium. Cl(-) stimulated the biosynthesis of pyoluteorin, thereby repressing 2,4-diacetylphloroglucinol biosynthesis. The cell-free extract from the bacteria grown without Cl(-) showed hig...

Background: Black pod rot disease of cocoa caused by (Phytophthora palmivora Butl.) is one the major diseases on plantations worldwide. Many attempts have been made to prevent or reduce infection pathogens, but they not provided optimum results. This study aims detect antibiotic genes in endophytic bacteria that can suppress black disease. Methods: Eight were isolated from healthy pods and twig...

fluorescent pseudomonads are important biocontrol agents showing capability to restrict or suppress phytopathogens, especially the fungal pathogens via production of some inhibitory metabolites and siderophores directly, and promote the plant growth through some different phytohormones. the objective of this research is to screen and introduce pseudomonas fluorescens utpf68 as a new biocontrol ...

Root inoculation of Arabidopsis thaliana ecotype Columbia with Pseudomonas fluorescens CHA0r partially protected leaves from the oomycete Peronospora parasitica. The molecular determinants of Pseudomonas fluorescens CHA0r for this induced systemic resistance (ISR) were investigated, using mutants derived from strain CHA0: CHA400 (pyoverdine deficient), CHA805 (exoprotease deficient), CHA77 (HCN...

The rhizobacterium Pseudomonas fluorescens CHA0 promotes the growth of various crop plants and protects them against root diseases caused by pathogenic fungi. The main mechanism of disease suppression by this strain is the production of the antifungal compounds 2,4-diacetylphloroglucinol (DAPG) and pyoluteorin (PLT). Direct plant growth promotion can be achieved through solubilization of inorga...

Pseudomonas fluorescens CHA0 produces several secondary metabolites, e.g., the antibiotics pyoluteorin (Plt) and 2,4-diacetylphloroglucinol (Phl), which are important for the suppression of root diseases caused by soil-borne fungal pathogens. A Tn5 insertion mutant of strain CHA0, CHA625, does not produce Phl, shows enhanced Plt production on malt agar, and has lost part of the ability to suppr...

ABSTRACT Fluorescent Pseudomonas spp. that produce 2,4-diacetylphloroglucinol (2,4-DAPG) have biocontrol activity against damping-off, root rot, and wilt diseases caused by soilborne fungal pathogens, and play a key role in the natural suppression of Gaeumannomyces graminis var. tritici, known as take-all decline. Diversity within phlD, an essential gene in the biosynthesis of 2,4-DAPG, was stu...