Author
Abbas, Hamed | |
ACCINELLI, CESARE - University Of Bologna | |
SHIER, W. THOMAS - University Of Minnesota |
Submitted to: Journal of Agricultural and Food Chemistry
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 4/19/2017 Publication Date: 4/19/2017 Publication URL: http://handle.nal.usda.gov/10113/5795772 Citation: Abbas, H.K., Accinelli, C., Shier, W. 2017. Biological control of aflatoxin contamination in U.S. crops and the use of bioplastic formulations of Aspergillus flavus biocontrol strains to optimize application strategies. Journal of Agricultural and Food Chemistry. 65(33):7081-7087. https://doi:10.1021/acs.jafc.7b01452. DOI: https://doi.org/10.1021/acs.jafc.7b01452 Interpretive Summary: While most efforts to reduce aflatoxins in harvested crops have had limited success at best, biocontrol has proven to be a successful strategy, particularly for peanuts in Georgia, corn across the southern US, cottonseed in Texas and Arizona and tree nuts in California. Commercial biocontrol products use a non-aflatoxigenic strain of Aspergillus flavus applied to the soil in association with some type of grain, which serves as a nutrient source to help the A. flavus take over the niche to which it was applied. A recent focus of research has been on use of corn starch-based bioplastic as a vehicle for the delivery of biocontrol A. flavus strains, particularly in the development of sprayable formulations. Spraying a biocontrol agent on corn leaves makes it possible to apply less A. flavus later in the growing season and still achieve effective lowering of aflatoxin contamination in harvested corn. The ultimate goal of this line of research is to develop a formulation and application technique that will allow the grower to use biocontrol only when long-range weather forecasts indicate it will be needed. Technical Abstract: Aflatoxin contamination has a major economic impact on crop production in southern USA. Reduction of aflatoxin contamination in harvested crops has been achieved by applying non-aflatoxigenic biocontrol Aspergillus flavus strains that can out-compete wild aflatoxigenic A. flavus, reducing their numbers at the site of application. Currently, the standard method for applying biocontrol A. flavus strains to soil is using a nutrient-supplying carrier (e.g., pearled barley for Afla-Guard®). Granules of bioplastic (partially acetylated corn starch) have been investigated as an alternative nutritive carrier for biocontrol agents. Bioplastic granules have also been used to prepare a sprayable biocontrol formulation that gives effective reduction of aflatoxin contamination in harvested corn kernels with application of much smaller amounts to leaves later in the growing season. The ultimate goal of biocontrol research is to produce biocontrol systems that can be applied to crops only when long-range weather forecasting indicates they will be needed. |