A. flavus is the primary causal agent of aflatoxin contamination
of cottonseed. The concern of aflatoxin contamination of cottonseed
in the United States is due to the feed-mediated transfer of
contaminated seeds to milk of dairy cows [5]. Aflatoxin contamination
of cottonseed is frequent in pre-mature seeds associated
with insect damage to the boll, particularly by pink boll worm [6].
The contamination also occurs after seed maturity and boll
opening, and involves direct infection of seed by A. flavus [6,7].
Biotic and abiotic factors, either nutritional or environmental
including temperature, pH, and drought stress, are also known to
trigger aflatoxin production in toxigenic Aspergillus species,
although the molecular mechanisms for these effects are still
unclear [8e11].