ARS | Publication request: Aflatoxin control through transgenic approaches

Submitted to: Toxin Reviews
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: November 28, 2008
Publication Date: May 19, 2009
Citation: Rajasekaran, K., De Lucca II, A.J., Cary, J.W. 2009. Aflatoxin control through transgenic approaches. Toxin Reviews. 28(2):89-101.

Technical Abstract: Control of preharvest aflatoxin contamination of susceptible crops such as corn, cotton, peanut, and tree nuts is possible through time consuming and expensive agronomic practices. Breeding for disease-resistant crops is also very time consuming and does not lend itself readily to combat the evolution of new virulent fungal races. Moreover, availability of known genotypes with natural resistance to mycotoxin-producing fungi is a prerequisite for the successful breeding program. While it is possible to identify a few genotypes of corn or peanuts that are naturally resistant to Aspergillus, we do not know whether these antifungal factors are specific to A. flavus. In crops like cotton, there are no known naturally resistant varieties to Aspergillus. So far, the best options available to us are through biocontrol and/or genetic engineering. Availability of transgenic varieties with antifungal traits is extremely valuable as a breeding tool. Use of fungicides or chemicals is costly and can add to the cost of production. Moreover, the growing concerns regarding environmental safety and ground water quality demand less dependence on agrochemicals. Disease-resistant transgenic crops would not only control mycotoxin-producing organisms such as A. flavus, A. parasiticus, and Fusarium spp., but also several microbial (fungal, bacterial, and viral) diseases which cause significant economic losses in crop production. This review explores recent advances regarding genetic engineering approaches towards the control of aflatoxin contamination using native and heterologous genes.