Comparative transcriptome analysis reveals the biocontrol mechanism of Bacillus velezensis E68 against Fusarium graminearum DAOMC 180378, the causal agent of Fusarium head blight

Abstract

Fusarium graminearumis the causal agent of Fusarium Head Blight, a serious disease affecting grain crops worldwide. Biological control involves the use of microorganisms to combat plant pathogens such asF.graminearum. Strains ofBacillus velezensisare common biological control candidates for use againstF.graminearumand other plant pathogens, as they can secrete antifungal secondary metabolites. Here we study the interaction betweenB.velezensisE68 andF.graminearumDAOMC 180378 by employing a dual RNA-seq approach to assess the transcriptional changes in both organisms. In dual culture,B.velezensisup-regulated genes related to sporulation and phosphate stress and down-regulated genes related to secondary metabolism, biofilm formation and the tricarboxylic acid cycle.F.graminearumup-regulated genes encoding for killer protein 4-like proteins and genes relating to heavy metal tolerance, and down-regulated genes relating to trichothecene biosynthesis and phenol metabolism. This study provides insight into the molecular mechanisms involved in the interaction between a biocontrol bacterium and a phytopathogenic fungus.