FfCOX17 is Involved in Fumonisins Production, Growth, Asexual Reproduction, and Fungicide Sensitivity in Fusarium fujikuroi

Abstract

Fusarium fujikuroi, a causal agent of Rice Bakanae Disease, produces secondary metabolites such as gibberellin, pigments bikaverin, and mycotoxins fumonisins. Fumonisins produced by F. fujikuroi pose a severe threat to human and animal health. The copper chaperone protein plays a critical role in different growth stages of plants, fungi, and yeasts, but their functions and regulation in fumonisin biosynthesis are still unclear. Here, a copper chaperone protein, FfCOX17, was identified in F. fujikuroi. The FfCOX17 deletion mutant (∆FfCOX17) exhibited decreased vegetative growth and asexual reproduction. The transcriptional level of the FfFUM2 gene was significantly induced in ∆FfCOX17, and the fumonisin production in ∆FfCOX17 mutants was significantly increased compared to wild-type F. fujikuroi, but the pathogenicity of ∆FfCOX17 mutants was unaffected, which may be caused by the no significantly changed gibberellin content. ∆FfCOX17 showed decreased sensitivity to oxidative stress, osmotic stress, and increased sensitivity to cell wall stress, heat shock stress, and high concentration glucose. In addition, ∆FfCOX17 also showed increased sensitivity to fungicide fluazinam and fludioxonil, and decreased sensitivity to phenamacril and prochloraz. Taken together, this study suggested that FfCOX17 is critical for fumonisin production, vegetative growth, asexual reproduction, and fungicide sensitivity, but is not required for the virulence function of F. fujikuroi on rice.

Effect of powdery mildew on interleaf microbial communities and leaf antioxidant enzyme systems

“…Plant pathogenic fungi would reduce their sensitivity due to their adaptation to fungicides, so the use of mechanisms such as antagonism and competition among microorganisms would become the main means of long-term effective biological control research (Kim et al 2017;Claassen et al 2021;Martínez-Diz et al 2021;Mao et al 2022). Therefore, we analyzed the microbial diversity of peony leaves at different disease levels in order to contribute to the biological control of powdery mildew.…”

The ATP Synthase Subunits FfATPh, FfATP5, and FfATPb Regulate the Development, Pathogenicity, and Fungicide Sensitivity of Fusarium fujikuroi

“…The F. fujikuroi wild-type strain A was preserved in the laboratory, and the deletion mutants were obtained from strain A. The culture media involved in this study included potato dextrose agar (PDA), minimal medium (MM), complete medium (CM), V8 juice medium (V8), CMC liquid medium, and YEPD medium [40].…”

“…Pathogenicity assays on rice were conducted as previously described [40]. The mycelial plugs were inoculated in test tubes, and each sample was repeated 10 times.…”