Field efficacy of two atoxigenic biocontrol products for mitigation of aflatoxin contamination in maize and groundnut in Ghana

Authors: AGBETIAMEH, DANIEL - International Institute For Tropical Agriculture; ORTEGA-BELTRAN, ALEJANDRO - International Institute For Tropical Agriculture; AWUAH, RICHARD - International Institute Of Tropical Agriculture (IITA); ATEHNKENG, JOSEPH - International Institute Of Tropical Agriculture (IITA); ELZEIN, ABUELGASIM - International Institute Of Tropical Agriculture (IITA); Cotty, Peter; BANDYOPADHYAY, RANAJIT - International Institute Of Tropical Agriculture (IITA)

Submitted to: Biological Control
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/15/2020
Publication Date: N/A
Citation: N/A

Interpretive Summary: Aflatoxins are highly toxic, cancer causing chemicals produced by some fungi and contaminating crops grown in warm regions of the world. Currently, the one of the most effective means of eliminating aflatoxins from foods is through biological control using non-aflatoxin producing fungi. Two biological control products Aflasafe GH01 and Aflasafe GH02 were tested in corn and peanut fields in Ghana. The frequency of the fungi comprising the biocontrol products was measured in soils prior to treatment, soils at harvest, and the crop at harvest for treated fields and paired control fields where no application occurred. The biocontrol fungi were significantly higher on treated crops than on control crops, and aflatoxins were significantly reduced in the treated crops to the extent that the crops could be sold in the high value international markets. These two biocontrol products present an inexpensive and highly effective means of reducing aflatoxins in Ghanaian crops.

Technical Abstract: Biological control is one of the recommended methods for aflatoxin mitigation. Biocontrol products must be developed, and their efficacy demonstrated before widespread use. Efficacy of two aflatoxin biocontrol products, Aflasafe GH01 and Aflasafe GH02, were evaluated in 800 maize and groundnut farmers’ fields during 2015 and 2016 in the Ashanti, Brong Ahafo, Northern, Upper East, and Upper West regions of Ghana. Both products were developed after an extensive examination of fungi associated with maize and groundnut in Ghana. Each product contains as active ingredient fungi four Aspergillus flavus isolates belonging to atoxigenic African Aspergillus Vegetative Compatibility Groups (AAVs) widely distributed across Ghana. An untreated control field was maintained for each treated field to determine product efficacy. Proportions of atoxigenic AAVs composing each product were assessed in soils before product application, and soils and grains at harvest. Significant (P < 0.05) displacement of toxigenic fungi occurred in both crops during both years, in all five regions. Biocontrol-treated crops consistently had significantly (P < 0.05) less aflatoxins (range = 76% to 100% less; average = 99% less) than untreated crops. Results indicate that both biocontrol products are highly efficient, cost-effective, environmentally safe tools for aflatoxin mitigation. Most crops from treated fields could have been sold in both local and international food and feed premium markets. Adoption and use of biocontrol products have the potential to improve the health of Ghanaians, and both income and trade opportunities of farmers, aggregators, distributors, and traders.