Aminopyrifen, a novel 2-aminonicotinate fungicide with a unique effect and broad-spectrum activity against plant pathogenic fungi

Aminopyrifen is a novel 2-aminonicotinate fungicide with unique chemistry and a novel mode of action. The fungicide showed high antifungal activity mainly against Ascomycetes and its related anamorphic fungi under <i>in vitro</i> and pot conditions (EC₅₀ values: 0.0039-0.23 mg/L and 1.2-12 mg/L, respectively). The active ingredient strongly inhibited germ-tube elongation of <i>Botrytis cinerea</i> below 0.1 mg/L and invasion into a plant. The compound exhibited no cross-resistance to commercial fungicides in <i>B. cinerea</i>. The antifungal agent showed high preventive efficacy and translaminar action. In the field, aminopyrifen controlled gray mold and powdery mildew at 150 mg/L. Our findings suggest that aminopyrifen is useful for protecting crops from various plant pathogens.