Aflatoxin contamination of maize and groundnut by Aspergillus section Flavi fungi is perennial in Ghana. Consumption of foods with high aflatoxin content can cause acute liver cirrhosis and death, while sub-lethal chronic exposure may cause cancer, stunting in children, immune system suppression, and impaired food conversion. Animal productivity likewise becomes affected when feeds contain high aflatoxin levels. This results in substantial health and economic burdens.
With support from the Africa RISING project, a management strategy using biocontrol products containing native atoxigenic A. flavus fungi to reduce crop aflatoxin content has been developed for use in Ghana by the International Institute of Tropical Agriculture (IITA) and partners. When products are applied at the right crop development stage, the atoxigenic fungi competitively displace aflatoxin-producers residing in treated fields and, in so doing, crop aflatoxin content is reduced.
Two biocontrol products, Aflasafe GH01 and Aflasafe GH02, each containing four atoxigenic A. flavus strains native to Ghana, were tested in maize and groundnut farmer fields in efficacy trials during 2015 and 2016. Competitive exclusion of aflatoxin producers by the atoxigenic strains and crop aflatoxin content were determined.
Key results from this work so far
- Significant (P <0.05) displacement of toxigenic fungi occurred in all years, regions, and crops. In addition, maize and groundnut from aflasafe-treated fields contained significantly (P <0.05) less aflatoxins (range = 98–100% less) than crops from untreated fields.
- The large majority of crops from treated fields could have been commercialized in both local and international food and feed premium markets.
These results demonstrate that aflasafe GH01 and aflasafe GH02 are efficient, cost-effective, environmentally friendly tools for aflatoxin mitigation across Ghana.
Results from the efficacy trials will be submitted to Ghana’s Environmental Protection Agency for registration of both products by December 2017. Once registered, both products will be available to maize and groundnut farmers across the country. IITA is in the process of identifying key partners for production, commercialization, and use of both Aflasafe products throughout Ghana at scale as part of the Aflasafe Technology Transfer and Commercialization Project, which is funded by the United States Agency for International Development (USAID) and the Bill & Melinda Gates Foundation.