Maize farmers broadcasting aflasafe in their field. Photo by Ranajit Bandyopadhyay.

Aflatoxins are chemical poisons produced mainly by the fungus Aspergillus flavus in maize, groundnuts, cassava, and yam chips. They undermine human health, are potent causes of cancer, suppress the immune system of humans and animals, and stunt children’s growth.

In trade, about US$1.2 billion in global commerce is lost annually due to aflatoxin contamination, with African economies suffering some US$450 million in yearly trade losses. Aflatoxins are also non-tariff barriers to international trade since agricultural products that have more than the permissible levels of contamination are rejected.

To address this, we worked with partners to develop a safe and natural biocontrol method that drastically cuts aflatoxin contamination in African food crops. The resulting product is called aflasafe™.

Collaborating with the United States Department for Agriculture – Agriculture Research Service, we demonstrated the ability of a natural fungus found in Nigeria to significantly reduce concentrations of aflatoxins in maize. On-station trials of aflasafe™ in Zaria, Ikenne, Mokwa and Ibadan showed a drop in aflatoxin contamination in maize by 50 to 99 percent.

With aflasafe™, native strains of A. flavus that do not produce aflatoxins (called atoxigenic strains) are applied to alter the fungal community on crops and throughout an area so that crops become less contaminated with aflatoxins. When properly done, these native atoxigenic strains competitively exclude aflatoxin producers.

This competitive exclusion principle of biological control will be used as a new type of intervention strategy to mitigate the negative effect of aflatoxins on human health and trade initially in Nigeria.

Competitive exclusion works by applying selected native atoxigenic strains to out-compete and exclude aflatoxin-producers during colonization of grains, thereby reducing levels of aflatoxin contamination.

We identified several atoxigenic strains native to Nigeria and Kenya that are useful for reducing aflatoxins. We are also identifying native atoxigenic strains for Burkina Faso and Senegal for similar aflatoxin biocontrol.

In 2009, Nigeria’s National Agency for Food and Drug Administration and Control provisionally registered aflasafe™ and permitted treatment of up to 100 ha of farmers’ fields.

Farmers participating in the field trials of aflasafe™ attest that the quality of their maize grains has significantly improved after the product’s application in their fields. On average, the farmers who treated their maize field with aflasafe™ achieved nearly 80 percent aflatoxin reduction in grains at harvest. The trials were coordinated by the Kaduna State Agriculture Development Program, and funded by the African Agricultural Technology Foundation and European Union’s MycoRed Project.

aflasafe™ is a trademark of IITA.