Growth and Aflatoxin Production by Aspergillus parasiticus in a Medium Containing Plant Hormones, Herbicides or Insecticides

The effect of some widely used plant hormones (indol-3-acetic acid and gibberellic acid), herbicides (gramoxone, stomp and treflan) and insecticides (malathion, actellic and guthion) on Aspergillus parasiticus growth and aflatoxin production in a synthetic medium was studied. Addition of indol acetic acid to the medium increased aflatoxin production more than gibberellic acid. Treflan at 5, 10 and 20 ppm levels caused a highly significant stimulatory effect on A. parasiticus growth and aflatoxin production. In contrast, stomp at 10 and 20 ppm produced the reverse effect. Guthion, an insecticide, caused a marked decrease in fungal growth and aflatoxin production. The inhibitory effect of insecticides under study on both fungal growth and aflatoxin production in effectiveness followed the sequence: guthion>actellic>malathion. At the recommended application rate (10 ppm), with the exception of indol acetic acid and treflan, all compounds suppressed mold growth and aflatoxin production.