Regional Conference on Aflatoxin Challenges in West African States, Accra, 18-20 Nov 2013 Aflatoxins, Agriculture and Technology Solutions Available for Abating the Aflatoxin Challenge Ranajit Bandyopadhyay IITA, Ibadan, Nigeria
With Safe Food
Aflatoxin Facts Highly toxic metabolite produced by the ubiquitous Aspergillus flavus fungus The fungus resides in soil and crop debris, infects crops and produces the toxin in the field and in stores Fungus carried from field to store Contamination possible without visible signs of the fungus
Disease Development & Weather Unlike most fungi, Aspergillus flavus is favoured by hot dry conditions. The optimum temperature for growth is 37 C, but the fungus readily grows between the temperatures of 25-42 C, and will grow at temperatures from 12-48C. Toxin contamination more when night temperatures are high Drought stress predisposes plants to aflatoxin Source: www.aspergillusflavus.org
Aflatoxin Contamination Occurs in Two Phases Phase I: Before Crop Maturity Developing crops become infected. Associated with crop damage (insect, bird, stress). Favored by high temperature (night) and dry conditions. Phase II: After Crop Maturity Aflatoxin increases in mature crop. Seed is vulnerable until consumed. Rain on the mature crop increases contamination. Associated with high humidity in the field & store, insect damage, and improper crop storage or transportation.
Aflatoxin (ppb)ppb) Peanut(n = 188) Maize (n = 241) Distribution (% samples) > 4 54 70 > 10 41 52 > 20 29 24 Descriptive statistics (ppb) Minimum < LOD < LOD Maximum 3487 838 Mean 111 33 Pre-Harvest Problem Aflatoxin in Groundnut and Maize at Harvest, 2012, Nigeria Increases in store LOD = Limit of Detection; States sampled: Nassarawa, Katsina, Kaduna, Kano, Bauchi, Jigawa & Niger
Aflatoxin Contamination: A Perennial Concern in Warm Climates Contamination is most severe at low elevations and during dry periods. During drought the zone with contamination expands. 35 N 35 S Zone with Perennial Contamination Risk
Prevalence of Aflatoxin Several African staple commodities affected High human exposure in Africa mother to baby Levels and frequency of occurrence high Concern for food and feed processors, government and emergency food reserve agencies, schoolfeeding Aflatoxins disproportionately impact the poor Highly toxic strains, conducive environmental conditions, traditional farming methods and improper grain drying and storage practices, unregulated markets
International Institute of Tropical Agriculture Institut international d agriculture tropicale
Aflatoxin Contamination in West Africa Primary products MTL = 10-20 ng/g Food products Maize: 4,000 Benin Peanut: 925 Burkina Sorghum: 80 Ghana Rice: 372 Nigeria Millet: 200 Nigeria Tiger nuts: 120 Nigeria Peanut paste: 3,278 Ghana Peanut sauce: 943 Ghana Leaf sauce: 775 Gambia Maize dough: 313 Ghana Kenkey: 524 Ghana Cashew paste: 366 Ghana Peanut oil: 500 Nigeria Yam flour: 7,600 Nigeria Local beer: 135 Nigeria Infant food: 19* Burkina International Institute of Tropical Agriculture Institut international d agriculture tropicale
Agriculture & Medical Prevention of Aflatoxinrelated Food Security and Health Effects Medical Early diagnosis Surveillance Provision of safe food Aflatoxin Intervention Awareness Regulation Enterosorption e.g. Novasil clay Pre-harvest Agriculture Post-harvest Food processing (Adapted from Wild and Hall, Mutation Res., 2000)
Pre- and post-harvest Interventions for Aflatoxins Pre-harvest Resistant cultivars, if available Biological control, e.g., aflasafe Irrigation and water conservation practices Post-harvest Sorting Insect control Improved drying and storage Aflatoxin testing Food / feed processing / detoxification methods / binders Alternative uses including blending Market development
Integrated Management The elements are: Awareness entire range of value chain participants Advocacy continental (PACA), regional, national, investors Technology Training farmers, transporters, traders, regulators, consumers Policies standards, harmonization, trade Institutions regulators, markets, testing, private sector Trade / Markets food/feed processors, poultry/fish industry Public good home consumption; urban and rural markets; WFP, HGSF
Resistant, High-Yielding Hybrids Kernel Screening Assay Aflatoxin (ppb) Grain yield (kg/ha) 8,000 7,000 6,000 5,000 4,000 3,000 2,000 1,000 0 Aflatoxin (ppb) Grain yield (kg/ha) 5474 5671 6438 334 396 400 488 6087 5685 Less toxin high yield 7115 800 809 816 956 6040 5891 5743 5662 Hybrids
Biocontrol Product: Aflasafe (Mixture of 4 native atoxigenic strains) Products ready for registration Nigeria, Senegal, Burkina Faso and Kenya Products under field testing Zambia Products under development Ghana, Tanzania and Mozambique Products development to start Mali, The Gambia, Uganda, Ethiopia, Rwanda, Burundi and South Sudan
Farmers treating maize and groundnut fields with Aflasafe in Nigeria MAIZE: Aflatoxin reduction (%) Stage 2009 2010 2011 2012 Harvest 82 94 83 93 Storage 92 93 x x 71% and 52% carry-over of inoculum 1 & 2 years after application PEANUT: Aflatoxin reduction (%) Stage Harvest Storage 2009 100 2010 95 80 2011 82 x Results from 482 on-farm trials
Aflasafe Plan & Plant Capacity: 5 tons/hour
Biocontrol x Resistance Aflatoxin (ppb) in Low-Aflatoxin Maize Lines With and Without Aflasafe Treatment Experimental variety Control At harvest Aflasafe After poor storage Control Aflasafe RSYN2-Y 19.6 1.7 RSYN3-W 6.9 1.8 SYN3-Y 18.4 1.7 TZB-SR (susc.) 57.5 4.7 462 44 627 38 387 19 1152 163 Combining management tactics increases extent of aflatoxin reduction
Training & Use by Farmers
Advocacy and Policies National and regionally harmonized standards in foods and feeds Intra-regional trade of safe food Enhanced capacity of regulators Alternative uses Disposal of contaminated material Regionally harmonized protocols for biopesticides registration Inclusion of aflatoxin in nutrition and health policies Aflatoxin alert system in Africa Critical role of PACA and RECs
Markets 60% maize consumed by farmers 40% sold in the market market demand for Aflasafe Poultry industry Export-oriented aggregators Food processors Large commercial farmers Smallholder farmers Market based Poultry feed Premium food market Export AgResults (Incentivecum-market based) Doreo Partner analysis
Challenges But Aflatoxin is a hidden problem Chemical analysis required Awareness is low Long incubation for expression of health impacts Regulations either non-existent or poorly enforced Market does not usually discriminate Demonstration of product value Lack of biopesticide manufacturers The value of a technology on the shelf is as much as the cost of the space it occupies on the shelf. Must translate knowledge into usable products and practices to benefit people
Pilot Implementation Value chain-centric:farmers and other value chain participants interest as the foundation of the action Action-oriented: Using practical methods to actively solve problems, not just talking about ideas, plans, or theories Innovation platform: problem solving by participants working regularly together to address common issues and challenges.
Innovation Platform Platform meetings with leadership and members of Poultry Association of Nigeria, feed manufacturers, maize aggregators, aflasafe farmers, vet professionals and regulators Poultry farmers to buy all aflasafe maize at a negotiated premium Agriculture ministry to fund NAFDAC to set up aflatoxin testing facilities in each state
Babban Gona Pilot Farmers cooperative with professional management Credit, inputs and technical services Yield enhancing practices Aflatoxin awareness Aflasafe use Aflatoxin testing 100% met standard Incentive for meeting aflatoxin standard Warehousing Output marketing linking to market Return profit after sale Farmers keep part of the harvest for family use
G-20 AgResults Aflasafe Pull mechanism Aflasafe is one of the first three pilots Provides incentives after demonstrating adoption Private sector driven, but focused on smallholder groups Implementers provide credit, inputs and technical services to increase yield Aflasafe purchased at cost to improve quality Maize tested for aflasafe strains; if present in large frequency, the implementers incentivized with $18.75/ton maize Implementers negotiate maize sale at premium Project provides aflatoxin awareness, training of implementers, and identifies potential market linkages Target: 200,000 ha in 4 years
Award-winning Research Charity Mutegi received the Norman Borlaug Award for Field Research and Application from the World Food Prize Foundation. Charity received this award in recognition for her work in various facets of aflatoxin management in Kenya, which included awareness raising, capacity building, establishing risk assessment data, and extending and potential deployment of a biological control product called aflasafe, for managing aflatoxin.
Summary Impact of aflatoxins have several development dimensions: post-harvest losses, nutrition, health, crops, livestock, fish, trade, markets, policies, institutions and politics Reduction of aflatoxin will improve human health, increase farm income, improve profitability of animal industries, increase regional and international trade, and reputation of African products in global markets
Ibadan IITA Nigeria Tucson USDA/ARS IITA, USDA, AATF & Doreo have Teamed up to Bring Aflatoxin Prevention to Africa Made Possible by Many National Partners in Ministries, Industry, and on the Farm For more information about aflatoxin biocontrol for Africa, check out: www.aflasafe.com
Experimental varieties Synergistic Effect of Resistance and Biocontrol in Reducing Aflatoxins at Harvest and after poor storage Resistance alone Aflatoxin reduction (%) Biocontrol alone Resistance + Biocontrol RSYN2-Y 66 (60) 91 (90) 97 (96) RSYN3-W 88 (46) 74 (94) 97 (97) SYN3-Y 68 (66) 91 (95) 97 (98) TZB-SR (Susc.) 58(1152) ppb 92 (86) % Reduction in experimental varieties compared to susceptible variety (TZB-SR) under natural conditions % Reduction in biocontrol treated plots compared to control untreated plots of of the the same experimental variety variety % Reduction in varieties with biocontrol compared to susceptible variety (TZB-SR) under natural conditions
Biocontrol x Resistance Aflatoxin (ppb) in Low-Aflatoxin Maize Lines With and Without Aflasafe Treatment Experimental variety Control At harvest Aflasafe After poor storage Control Aflasafe RSYN2-Y 19.6 1.7 RSYN3-W 6.9 1.8 SYN3-Y 18.4 1.7 TZB-SR (susc.) 57.5 4.7 462 44 627 38 387 19 1152 163 Combining management tactics increases extent of aflatoxin reduction Mycored Europe, 28 May, 2013