Volatile organic compounds of Bacillus velezensis 6W1 inhibit the growth and toxin production of Fusarium graminearum

Abstract:

[Background] Wheat scab and Fusarium toxin pollution caused by Fusarium graminearum complex seriously affect the yield and quality of wheat. Volatile organic compounds (VOC) produced by biocontrol strains can be used for the biocontrol of plant diseases. [Objective] To provide a theoretical basis for the full application of biocontrol strains. [Methods] We collected VOC from Bacillus velezensis 6W1, an antagonistic strain isolated in the previous study. The two-tier culture dish was employed to study the effects of VOC on the mycelial growth of F. graminearum. The plate confrontation-fumigation assay was employed to examine the effects of VOC on the spore germination and deoxynivalenol (DON) production of F. graminearum. The components of VOC were qualitatively analyzed by gas chromatography-ion mobility spectrometry (GC-IMS). [Results] The VOC produced by B. velezensis 6W1 inhibited the growth and DON production but had no effect on the spore germination of F. graminearum. The results of GC-IMS showed that the VOC produced by the strain mainly included esters, alcohols, aldehydes, alkenes, and ketones. The inhibitory effect of the standard substance of each component was tested. The results showed that these substances inhibited the growth and DON production of F. graminearum. [Conclusion] In summary, B. velezensis 6W1 can produce VOC capable of inhibiting the growth and toxin production of F. graminearum. This strain demonstrates great potential in the development of biocontrol products, and its VOC also have high research and application values in the prevention and control of plant diseases.