A novel Burkholderia pyrrocinia strain effectively inhibits Fusarium graminearum growth and deoxynivalenol (DON) production.

Background: Fusarium graminearum is a devastating fungal pathogen that poses a significant threat to global wheat production and quality. Control of this toxin-producing pathogen remains a major challenge. This study aimed to isolate strains with antagonistic activity against F. graminearum and at the same time to analyze the synthesis of deoxynivalenol (DON), in order to provide a new basis for the biological control of FHB.

Results: Total of 69 microorganisms were isolated from the soil of a wheat-corn crop rotation field, and an antagonistic bacterial strain F12 was identified as Burkholderia pyrrocinia by molecular biology and carbon source utilization. F. graminearum control by strain F12 showed excellent biological activities under laboratory conditions (95.8%) and field testing (63.09%). Meanwhile, the DON content of field-treated wheat grains was detected the results showed that F12 have significantly inhibited of DON, which was further verified by qPCR that F12 produces secondary metabolites that inhibit the expression of DON and pigment-related genes. In addition, the sterile fermentation broth of F12 not only inhibited mycelial growth and spore germination, but also prevented mycelia from producing spores.

Conclusion: In this study B. pyrrocinia was reported to have good control of FHB and inhibition of DON synthesis. This novel B. pyrrocinia F12 is a promising biological inoculant, providing possibilities for controlling FHB, and a theoretical basis for the development of potential biocontrol agents and biofertilizers for agricultural use. © 2024 Society of Chemical Industry.