Fungal Vapors Reveal Complex Powers and Pitfalls in Aflatoxin Crop Defense – Bioengineer.org

Fungal Vapors Reveal Complex Powers and Pitfalls in Aflatoxin Crop Defense  Bioengineer.org

Agricultural commodities worldwide face persistent jeopardy from fungal pathogens in the genus Aspergillus, whose aggressive colonization yields toxic secondary metabolites known as aflatoxins that threaten international food security and human health. Aflatoxins represent substantial agricultural and economic threats resulting in financial losses measured in billions of dollars, alongside severe medical conditions such as acute aflatoxicosis and chronic hepatocarcinogenicity. Among the various chemical iterations identified to date, aflatoxin B1 stands out as the most potent naturally occurring carcinogen, synthesized predominantly by Aspergillus flavus and related taxa within section Flavi. While pre-harvest biocontrol strategies utilizing non-aflatoxigenic strains of Aspergillus flavus have been deployed for decades across staple crops like corn, peanuts, and tree nuts to displace toxigenic isolates through competitive exclusion, these protective field interventions often experience waning efficacy once harvested commodities transition into storage bins and transport networks.

Addressing this post-harvest vulnerability, researchers at the United States Department of Agriculture Agricultural Research Service Southern Regional Research Center in New Orleans, Louisiana, investigated whether volatilized extrolites secreted by non-aflatoxigenic biocontrol fungi could serve as natural biofumigants during storage and shipping. Previous discoveries from this research group established that specific non-aflatoxigenic strains do not rely solely on vegetative competitive displacement or physical space competition, but also emit bioactive soluble and airborne chemical blends capable of hindering fungal proliferation and toxic biosynthesis. In earlier