ABSTRACT Anthracnose caused by Colletotrichum spp. is among the most economically significant diseases affecting strawberry ( Fragaria × ananassa ) production worldwide. Despite its importance, information on the Colletotrichum species affecting strawberry in Argentinean production regions remains scarce. This study aimed to identify and characterise the Colletotrichum species associated with strawberry anthracnose in the Argentine Littoral, a key production area. Between 2018 and 2024, sampling of symptomatic fruits across multiple fields and cultivars led to the isolation of 40 monoconidial strains. Morphological characterisation was complemented by multilocus phylogenetic analyses targeting tub2 , gapdh and his3 gene regions. Colonies were white to cream with salmon‐coloured acervuli, and produced cylindrical to clavate conidia with one acute end, averaging 14.55 × 3.96 μm. BLAST analyses of tub2 sequences showed 100% identity with Colletotrichum nymphaeae , and multilocus phylogenetic analyses consistently placed all isolates within a well‐supported C. nymphaeae clade, confirming this species as the dominant causal agent of strawberry anthracnose in the region. Pathogenicity tests were conducted on both wounded and unwounded fruits to confirm virulence. Disease symptoms developed rapidly, with necrotic lesions appearing within 3–4 days post‐inoculation and progressing to extensive fruit rot under controlled conditions, highlighting the pathogen's aggressiveness. The high frequency and broad geographic distribution of C. nymphaeae across cultivars and production seasons indicate a stable presence in the regional agroecosystem, likely contributing to persistent disease outbreaks. These results provide a critical foundation for future epidemiological studies and fungicide sensitivity assessments, supporting the development of targeted and effective integrated disease management strategies tailored to the local pathogen population.
Fernandez et al. (Thu,) studied this question.