Biological control of Aflatoxins
Peter J. Cotty,
Agricultural Research Service, USDA
University of Arizona, Tucson, Arizona
International Institute of Tropical Agriculture
Breakout Session 4 on Food Security
Science Forum 2013
Nutrition and health outcomes: targets for agricultural research,
Bonn, Germany, 23‒25 September 2013
Aflatoxins are highly toxic cancer causing fungal metabolites that
contaminate crops and impact human health, development, and income
throughout the warm production regions.
With a single biological control technology aflatoxins can be reduced and
eventually eliminated on treated crops, rotation crops, and throughout
the environment. $50 million over the next decade will be used to adapt
and disseminate this technology across sub-Saharan Africa.
Aflatoxin prevention will have health and economic impacts throughout
the warm regions such as sub-Saharan Africa, Southeast Asia, and South
One Technology Many Benefits
This technology will reduce aflatoxins in all susceptible crops
(Groundnut, Maize, Chilies, etc.) both prior to and after harvest.
Protection remains with the crop until it is actually consumed.
The technology is adaptable to any target location.
Does not assert selective pressure on aflatoxin producers.
The technology works every time and is Less Expensive than sampling a small
holders field and analyzing it for aflatoxins.
Removes the need to increase and maintain host resistance to aflatoxins during
the process of selecting high yielding cultivars.
Resistance to aflatoxin contamination has been sought for over 3 decades in
both groundnut and maize without development of commercially acceptable
During Crop Development
Irrigation, Weed Control, Fertilize
Best cultivars, Insect Control
Rapid, Dry, No Damage
Sort, Cull, Discard, Add binders.
Dry, prevent moisture, cool
Prevent damage: insects, rodents
Prevent Formation of Dangerous Aflatoxin Levels
Protect Crops Until Use
A single application at 10 kg/hectare is
enough to consistently reduce aflatoxins
in maize, groundnut, and other crops.
Biological Control: One Action by the Farmer Reduces Aflatoxins under all Conditions
Either Sorghum, Wheat,
or Barley are used.
The grain is killed by
cooking before use.
Sorghum is used in
Isolates (%) in Applied Atoxigenic Strain
0 20 40 60 80 100
Dots Represent Values
for Replicate Plots
Aflatoxin in Crop versus Atoxigenic Incidence
Cotty, 1994. Phytopathology:1270-1277.
MAIZE: Aflatoxin reduction (%)
Stage 2009 2010 2011 2012
Harvest 82 94 83 93
Storage 92 93 x x
PEANUT: Aflatoxin reduction (%)
Stage 2009 2010 2011
Harvest - 95 82
Storage 100 80 x
Results from 482
71% and 52% carry-over of
inoculum 1 & 2 years after
Crops are Protected in the Field and During Storage
Aflatoxin reduction after 4 months poor storage (Field Treated Crops – Nigeria)
Birnin Gwari Lere Maigana Pampaida
85% 82% 99% 95%
% reduction in aflatoxin content in treated fields over control
Farmers threshing groundnut
Farmers treating groundnut fields with AflaSafe
2010 : 87% at harvest; 89% after Storage
2011: 82% at harvest; 93% after Storage
2012: 86% at harvest; 83% after Storage
38 Farms Treated in 2010
40 Farms Treated in 2011
196 Farms Treated in 2012
Hola Irrigation Scheme, Coast Province, Kenya: 2012 Tests
First Season Farmer Field Tests
Treatment = 10 kg/ha Aflasafe KN01
Percent of Fields
Deadly (3,700 ppb & 2,270 ppb)
• Ministries of Health, Trade, & Agriculture
• African Union and it’s Regional Economic Commissions
• Technical Organizations (IR-4,
• Regulatory Organizations
• Farmers & Farmer Organizations
• Universities & Cooperative Extension
• Processors, Food & Feed Producers
• Producers of Poultry, Fish, Pork, etc.
• Middlemen, Marketers, Exporters
• Implementers, Public & Private
Engage, Adapt, Disseminate, Develop, Optimize, repeat…..
Pesticide Registrations, Agronomic Practices, Fungal Germplasm,
Business Models, Manufacturing…..
1st Generation Large-Scale Manufacture
Arizona Cotton Research & Protection Council
2nd Generation Large-Scale Manufacture
International Institute of Tropical Agriculture
3rd Generation Large-Scale Manufacture
4th Generation Large-Scale Manufacture
5th Generation Large-Scale Manufacture
Return on Investment
• More Health
– Improved Immune Systems
– Reduced Stunting
– Slower spread of HIV
– Better Utilization of Nutrients
– Less Cancer
– Healthier Lives
The very reasons aflatoxins are regulated stringently in the developed world.
• More Money
– Export Value of Crops and Crop Products will be Increased.
• The biological control works. It can be the principal tool for
eliminating aflatoxins from the food supply and the environment.
• Elimination of aflatoxins will have broad benefit.
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