Aminopyrifen, a novel 2-aminonicotinate fungicide, inhibits growth and deoxynivalenol biosynthesis in Fusarium graminearum

Fusarium graminearum , the major causal agent of Fusarium head blight (FHB) in cereals, threatens global wheat production and food safety through yield losses and contamination with the mycotoxin deoxynivalenol (DON). Here, we evaluated aminopyrifen, a novel 2-aminonicotinate fungicide, for its efficacy and mechanism of action against F. graminearum . Sensitivity assays of 103 field isolates revealed potent inhibition of mycelial growth (mean EC₅₀ = 0.0547 μg/mL) with no resistant strains detected. Aminopyrifen disrupted hyphal and conidial morphology, suppressed toxisome formation, and markedly reduced DON biosynthesis by downregulating TRI gene expression. Functional analyses showed that the acyltransferase FgGWT1 is essential for fungal growth, conidiation, virulence, and toxisome formation, and its inhibition by aminopyrifen phenocopied gene deletion. These findings establish aminopyrifen as a promising candidate fungicide with a novel target, offering potential for effective FHB management and reduced DON contamination in wheat. • Aminopyrifen showed strong antifungal activity against 103 F. graminearum isolates. • Aminopyrifen disrupted toxisome formation and inhibited DON production and TRI genes. • FgGWT1 is essential for growth, conidiation, virulence, and aminopyrifen response. • FgGWT1 interacts with Tri1, playing a critical role in toxisome formation.