Biological control of aflatoxins in Africa: current status and potential challenges in the face of climate change

Authors: BANDYOPADHYAY, R - International Institute Of Tropical Agriculture (IITA); ORTEGA-BELTRAN, ALEJANDRO - University Of California Agriculture And Natural Resources (UCANR); AKANDE, A - International Institute Of Tropical Agriculture (IITA); MUTEGI, C - International Institute Of Tropical Agriculture (IITA); ATECHNKENG, J - International Institute For Tropical Agriculture; KAPTOGE, L - International Institute Of Tropical Agriculture (IITA); SENGHOR, A - La Direction De La Protection Des Vegetaux (DPV); Adhikari, Bishwo; Cotty, Peter

Submitted to: World Mycotoxin Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/21/2016
Publication Date: 11/10/2016
Citation: Bandyopadhyay, R., Ortega-Beltran, A., Akande, A., Mutegi, C., Atechnkeng, J., Kaptoge, L., Senghor, A.L., Adhikari, B.N., Cotty, P.J. 2016. Biological control of aflatoxins in Africa: current status and potential challenges in the face of climate change. World Mycotoxin Journal. 9(5):771-789.

Interpretive Summary: Aflatoxins are toxic fungal metabolites that frequently contaminate crops. These toxins can inhibit human development, cause cancer, suppress the immune system and cause death from liver failure. Occurrence of aflatoxins in crops greatly reduces marketability and strongly reduces the human condition across sub-Saharan Africa. The only successful tool for preventing aflatoxin contamination pre-harvest is a type of biological control that utilizes atoxigenic strains of A. flavus as active ingredients. Over the past 10 years, USDA/ARS has partnered with the International Institute of Tropical Agriculture to adapt biological control with atoxigenic strains of A. flavus for practical implementation in Africa. Funding from many donors has supported selection of atoxigenic genotypes and development of biological control formulations, based on the initial work in the US, that are effective in Africa on corn and peanut. The result is a safe and environmentally friendly technology that is being adapted over an increasing area in order to relieve detremental influences on these deadly toxins across the African continent.

Technical Abstract: Aflatoxin contamination of crops is frequent in warm regions across the globe, including large areas in sub-Saharan Africa. Crop contamination with these dangerous toxins transcends health, food security, and trade sectors. It cuts across the value chain, affecting farmers, traders, markets, and finally consumers. Diverse fungi within Aspergillus section Flavi contaminate crops with aflatoxins. Within these Aspergillus communities, several genotypes are not capable of producing aflatoxins (atoxigenic). Carefully selected atoxigenic genotypes in biological control (biocontrol) formulations efficiently reduce aflatoxin contamination of crops when applied prior to flowering in the field. This safe and environmentally friendly, effective technology was pioneered in the US, where almost a million acres of susceptible crops are treated annually. The technology has been improved for use in sub-Saharan Africa, where efforts are under way to develop biocontrol products, under the trade name Aflasafe, for 11 African nations and more are expected to be developed. In parallel, state of the art technology has been developed for large-scale manufacturing of Aflasafe products. Here, the benefits of aflatoxin biocontrol technologies are discussed along with potential challenges, including climate change, likely to be faced during the scaling-up of Aflasafe products. Lastly, we respond to several apprehensions expressed in the literature about the use of atoxigenic genotypes in biocontrol formulations.