This document discusses comprehensive strategies for managing aflatoxin in groundnuts. It begins by explaining that aflatoxin is produced by fungi and can contaminate various crops like groundnuts, maize, and sorghum. It then lists factors that can favor aflatoxin contamination at different stages from pre-harvest to post-harvest. The document advocates for an integrated management approach using cultural practices, host plant resistance, and post-harvest processing. Large-scale demonstrations in India and Gujarat showed that integrated management can successfully reduce average aflatoxin levels to below 10 ppb.

1. Comprehensive Strategies for Aflatoxin
Management in Groundnut
Dr. M S Basu
Formerly, Director
National Research Centre for Groundnut (ICAR)
Visiting Scientist, ICRISAT (CGIAR)
UNIDO International Consultant on Aflatoxin
Malawi, Africa
muktisadhan@gmail.com

2. Aflatoxin
A secondary metabolite produced by
Aspergillus flavus and A. parasiticus
having carcinogenic effect
[Aspergillus flavus + toxin]

3. Aflatoxin: Maize, Groundnut,
Sorghum, Peal millet,
Cotton seeds, Chilli, etc.
Fumonisin: Maize, Groundnut, Beans,
etc.
Ochratoxin: Maize, Chilli, Sorghum,
Pearl millet, etc.
Toxins affecting important crops

4. Permissible Limits of Aflatoxin (ppb)
EU
Groundnut (unsorted) 5 B1
10 B1+B2+G1+G2
Groundnut sorted 2 B1
4 B1+B2+G1+G2
USA (all foods) 20
Australia (peanut) 15
Canada (nuts) 15
France (all foods) 10
India (all foods) 30
China (cereals) 50

5. To decide comprehensive
management strategies - - -
Essential to understand
Conditions favoring Aflatoxin
contamination

6. Soil population of A. flavus varies depending on
soil types and crop rotations
Soil-water-nutrient balance during the crop
growth period
Mechanical injury to pods during intercultural
operations
Damage to pods due to soil insect-pests
Prolonged moisture stress associated with high
temp. at pod maturity
Delayed harvest (over maturity)
Pre-Harvest Stages

7. Stem Rot
Pod Rot
Diseases also triggers Aflatoxin contamination

8.  Harvesting immediately after irrigation with
high initial pod moisture followed by quick
drying under hot sun
 Gleaning of pods from soil after harvest
 Mechanical damage to the pods/ kernels
during processing
 Storing produce above 8-9 % moisture level
 Hot and humid storage condition
 Adding moisture during decortication
 Packing of kernels at added moisture level
Post-Harvest Stages

9. Dimension of Aflatoxin Contamination Problem in
Major Groundnut Growing States of India
District Pod
samples
Infection
%
AF Population
(cfu x 103/g soil)
Anantpur 928 83 420
Chittoor 178 95 530
Cuddapah 30 85 092
Kurnool 181 88 740
Kolar 24 70 069
Tumkur 175 89 420
Contd…
Andhra Pradesh & Karnataka

10. District Pod
samples
Infection
%
AF Population
(cfu x 103/g of soil)
Junagadh 428 70 386
Amreli 192 70 216
Porbandar 133 81 160
Rajkot 239 58 220
Gujarat

11. Distribution of A. flavus in Different Districts of
Gujarat during Rainy & Post-rainy Season
Population changes with seasonal variation and
more in Rainy season
District Aspergillus flavus
Post Rainy Rainy
Junagadh 39.30 51.40
Amreli 37.80 48.30
Bhuj 22.90 41.40
Bhavnagar 13.80 69.00

12. The Fact Remains:
 It’s a complex problem
 No single solution
 No dependable genetic resistance
 No transgenic for commercial
cultivation

13. Integrated Management of Aflatoxin in
Groundnut
(a): Host Plant Resistance
(b): Cultural – Good Agronomic Practices
Approaches:
(c): Biocontrol – Use of Non-toxigenic
Strains
(d): Mechanical – Efficient Post-harvest
Processing, Decortication

14. Available Technological Options
• Cultural management considered as best
option that includes:
 Application of bio-control agents
 Use of tolerant varieties (testa, drought,
foliar diseases)
 Practice in situ moisture conservation
 Harvest at optimum physiological maturity
 Subject to wind-row drying (plant along
with pods, in small heaps)
 Mechanical threshing and segregation
 Storage of fully dried pods (8% moisture)
in well ventilated, leak-proof godown

17. At Soil Level:
• Native populations of Aspergillus
• Activation of the fungus due to changes
in soil-water-nutrition balance
• Soil pests
Factors:
• Deep Ploughing; exposing soil to hot sun
• Crop rotation
• Soil solarization
Prevention:

18. At Plant Level
• Acute and prolonged moisture stress
• High temperatures
• Over maturity
• Varietal selection
• Soil moisture management
• Harvesting at optimum maturity
Factors:
Prevention:

19. At Harvesting and Processing Level
• Mechanical damage
• High initial pod moisture
• Insufficient drying
• Warm & humid storage conditions
• Removal of damaged & immature pods
• Mechanical separation of well-filled pods
• Quick natural drying in small heaps
• Storage of pods at 8-9% moisture in well
ventilated godown free from humidity
Factors:
Prevention:

20. Village/Farmer
(7) / (53)
Harvest
(Sum/Kh)
Sample
drawn
Aflatoxin
(µg/Kg)
K. Reddy Palli (8) Apr. 97 Sep. 97 0 - 5.8
Oddupalli (9) Apr. 97 -do- 0 - 6.4
Rekulakunta (10) Apr. 96 -do- 0 - 25.2
Cherlapalli (5) Nov. 97 Dec. 97 0 - 28.4
B. Samudram (5) Nov. 97 Feb.98 0 - 17.7
Akuthotapalli (7) Nov. 97 Feb. 98 5.1 - 25.9
Venkatapuram (9)
Corresponding
Nov. 97
Control
Apr. 98
In 3-5 months
4.7 - 24.0
110 - 383
Reducing Groundnut Aflatoxin Risk (AP-UNDP)

21. Large Scale Demonstrations in Gujarat
• The A.P experience was utilized in Kutch-Bhuj
(on the direction of Agril. Advisor to PM, GoI)
• 220 Demos (1 acre each) conducted at
Nakhatrana Netra, Kotada, involving 226
farmers (2001-02)
• 440 samples (2 from each Demo) were analyzed
for Aflatoxin using HPLC
• Majority of samples were within 0.3 to 8.8 ppb
• The highest load recorded: 184 ppb

22. Significant Outcome
• Integrated Management successfully
reduced aflatoxin load on an average :
< 10 ppb - as against 110 - 383 ppb
as found in corresponding traditional
produce in two different seasons