Investigation of symbiotic-like interactions between Pseudomonas chlororaphis and non-pathogenic Fusarium sp. for enhanced biopreparation potential

The rhizosphere layer of the soil is a complex environment where various organisms interact with each other. Understanding this complex structure and utilising its interactions in industry can provide significant benefits in many areas, particularly in sustainable agriculture. In this study, the symbiotic effects between plant growth-promoting (PGP) Pseudomonas chlororaphis and non-pathogenic Fusarium sp. were examined, and symbiotic-like culture experiments were conducted for potential biopreparation production. Initially, the PGP properties of the interacting species were qualitatively screened, and their non-pathogenicity was confirmed in vitro. Then, symbiotic-like culture trials were performed with the selected species. Subsequently, the quantitative PGP properties of these species, both individually and in symbiotic-like culture, were determined. The symbiotic-like culture significantly enhanced phosphate solubilization and IAA production efficiency by approximately 70%. Moreover, the antifungal effects of all symbiotic-like cultures increased and remained effective for 15 days. This study demonstrates the potential of harnessing microbial interactions in the rhizosphere to develop biopreparations with enhanced plant growth-promoting and antifungal properties. Based on the results, important steps have been taken by clarifying the naturally occurring symbiosis in the rhizosphere of soil and paving the way to develop biopreparations with higher efficiency by leveraging interactions between microorganisms.