Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: 10/31/2007
Publication Date: 6/30/2008
Citation: Brown, R.L., Chen, Z., Menkir, A., Cleveland, T.E., Bhatnagar, D. 2008. Strategies for the prevention of preharvest aflatoxin contamination of maize. In: Stevens, C. and Khan, V.A. (eds) Recent Advancement in Agriculture, Research Signpost, Kerala, India. p.131-150.
Technical Abstract: Aflatoxin contamination of maize by the fungi Aspergillus flavus and A. parasiticus poses serious health hazards to humans and animals worldwide. This alarming fact, along with the institution of regulations in many countries to control the occurrence of aflatoxins in foods and feed, have stimulated research aimed at eliminating its presence in maize. When possible, cultural management practices that limit conditions favoring aflatoxin formation should be practiced, however, these are not always cost effective to growers. Host resistance, always a potentially valuable approach for combating crop disease, due to more recent innovations in germplasm screening techniques and the identification of resistant maize lines, now may be closer to realization. Breeding strategies, including the use of a laboratory-based kernel screening assay, are developing germplasm not only with resistance to aflatoxin formation but also with good agronomic characteristics. The identification of traits in resistant germplasm may provide clarity as to the mechanisms of aflatoxin-resistance, as well as lead to markers for use in breeding programs. Proteomics has accelerated the identification of proteins that may be involved in resistance. Other naturally-occurring compounds are also being investigated for use against aflatoxigenic fungi. A. flavus genomics should speed up our understanding of host-pathogen interactions and possibly contribute to the development of resistance against aflatoxin biosynthesis. The biological control strategy using A. flavus atoxigenic strains to hinder toxin-producing strains, now widely employed to protect cottonseed in Arizona, may soon be used to protect maize.