Biological control of Aflatoxins

Peter J. Cotty,

Agricultural Research Service, USDA

University of Arizona, Tucson, Arizona

Ranajit Bandyopadhyay,

International Institute of Tropical Agriculture

Ibadan, Nigeria

Breakout Session 4 on Food Security

Science Forum 2013

Nutrition and health outcomes: targets for agricultural research, Bonn, Germany, 23‒25 September 2013

Opportunity 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 America.

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 cultivars.

During Crop Development

Irrigation, Weed Control, Fertilize

Best cultivars, Insect Control

During transport

Rapid, Dry, No Damage

During Processing

Sort, Cull, Discard, Add binders.

During Storage

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.

Nigeria

Biological Control: One Action by the Farmer Reduces Aflatoxins under all Conditions

As Applied

After

Fungal Growth

Either Sorghum, Wheat,

or Barley are used.

The grain is killed by

cooking before use.

Sorghum is used in

Africa.

Afl

ato

xin

B1 (

ng

/g X

10,0

00

)

Isolates (%) in Applied Atoxigenic Strain

0

1

2

3

4

5

6

7

8

9

0 20 40 60 80 100

Dots Represent Values

for Replicate Plots

Aflatoxin in Crop versus Atoxigenic Incidence

Cotty, 1994. Phytopathology:1270-1277.

www.iita.org

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

on-farm trials

71% and 52% carry-over of

inoculum 1 & 2 years after

application

Crops are Protected in the Field and During Storage Aflatoxin reduction after 4 months poor storage (Field Treated Crops – Nigeria)

0

200

400

600

800

Birnin Gwari Lere Maigana Pampaida

Afl

ato

xin

(p

pb

) Control

Treated

96

14

271

49

646

17

171

9

85% 82% 99% 95%

% reduction in aflatoxin content in treated fields over control

www.iita.org

Farmers threshing groundnut

Farmers treating groundnut fields with AflaSafe

Aflatoxin Reduction:

2010 : 87% at harvest; 89% after Storage

2011: 82% at harvest; 93% after Storage

2012: 86% at harvest; 83% after Storage

Senegal

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

Tota

l Aflato

xin

s Deadly (3,700 ppb & 2,270 ppb)

Safe Food

Partners • 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

• Manufacturers

Plan

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

Phoenix, Arizona

2nd Generation Large-Scale Manufacture International Institute of Tropical Agriculture

Ibadan, Nigeria

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.

Punch Line

• 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.