The regulation and ecological relevance of 2,4-diacetylphloroglucinol-producing fluorescent Pseudomonas spp.

Abstract

2,4-diacetylphloroglucinol (2,4-DAPG)-producing fluorescent Pseudomonas species is a group of ubiquitous root colonizing gram-negative bacteria, which are well known for their biological control activity against many soilborne pathogens. Soilborne pathogens are responsible for a large loss of crop yield worldwide and they are difficult to control and application of pesticides are insufficient to control root diseases of important crop plants. Using 2,4-producing fluorescent Pseudomonas species as a biological control agent might contribute to the control of root diseases of important crop plants and increase crop production in a sustainable manner. However, the precise regulation and the mode of action of the antibiotic 2,4-DAPG is not fully known. Furthermore, the soil surrounding the plant’s roots sustains a large microbial community with members that can negatively or positively affect 2,4-producing fluorescent Pseudomonas species. These largely unknown biotic interactions makes it difficult to use 2,4-producing fluorescent Pseudomonas species as a biocontrol agent. Elucidating the mechanism by which 2,4-DAPG produced by fluorescent Pseudomonas species can effectively suppress plant diseases and how the root microbiome affects 2,4-DAPG production will open new doors for the biocontrol of pathogens and increasing the crop quality and productivity.