2025/07/08 by Jonathan Thomas Puglisi, Achour Amiri · 1 voice
Agricultural and Biological Sciences · Biochemistry, Genetics and Molecular Biology · #Mycotoxins in Agriculture and Food #Plant Pathogens and Fungal Diseases
paper · doi:10.1094/pdis-04-25-0882-re
openalex publication_date 2025/07/08 · openalex created_date 2025/07/09 · openalex updated_date 2026/06/11
Blue mold caused by Penicillium expansum leads to significant fruit loss to pome fruit packers and raises food safety concerns for fruit processors owing to patulin (PAT) contamination in processed products. The disease is primarily managed through postharvest applications of thiabendazole (TBZ), pyrimethanil (PYR), and fludioxonil (FDL). However, P. expansum has developed resistance to these commonly used fungicides. In 2021 and 2022, high levels of PAT were detected in several processed apple lots in Washington State, raising concerns about a potential link between fungicide resistance and increased PAT production. This study evaluated the mycotoxigenic potential of 15 P. expansum isolates, either sensitive to all three fungicides or having developed single, dual, and triple resistance to TBZ, PYR, and FDL, in vitro and on apples in long-term storage. There were no significant differences in PAT production between isolates or sensitivity resistance phenotypes, and they ranged between 7.8 and 13.42 mg/kg in malt extract broth at 1.5°C after 15 days. On ‘Fuji’ apples, PAT production increased slightly between 60 and 180 days of storage at 1.5°C. Although resistance phenotype had no significant effect (P = 0.581) on PAT production on apples, individual isolates exhibited significant differences (P < 0.001). A significant negative correlation and several nonsignificant correlations were observed between the isolate virulence and PAT production, but no significant correlation was found at the resistance phenotype level. These findings suggest that PAT production is an inherent trait of P. expansum isolates and that acquiring resistance to fungicides does not necessarily influence their mycotoxigenic potential.