Abstract
Aspergillus flavus and Aspergillus parasiticus produced ethylene during early growth. However, the onset of toxin biosynthesis was marked by the absence of ethylene evolution. 2-Chloroethyl phosphonic acid, an ethylene-generating compound, inhibited aflatoxin biosynthesis in vivo. The reciprocal relationship between the production of aflatoxin and ethylene by the organism may indicate the involvement of the latter in the regulation of aflatoxin biogenesis.