Maize Stored Pests Control by PICS-Bags: Technological and Economic - - PDF document

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Maize Stored Pests Control by PICS-Bags: Technological and Economic Evaluation

Kerstin Hell, Kukom Edoh Ognakossan, Agbeko Kodjo Tonou, Yendouban Lamboni, Kokou Edoh Adabe and Ousmane Coulibaly

5th World Cowpea Conference in Saly, Senegal

27 September - 1 October 2010

Outline

• 1. Introduction
• 2. Traditional storage system
• 3. PICS bag trial
• 4. Key Results
• 5. Conclusion
• 6. Acknowledgements

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• Environmental conditions, traditional farming methods and

improper grain drying and storage practices facilitate quality reduction and insect infestation

• Grain losses due to Insects

– >30% in maize stores infested with Prostephanus truncatus – 10-12 % in maize infested with Sitophilus zeamais

Traditional storage system

• Several African staple commodities are

affected by high losses due to insects – maize, millet, groundnut, cassava, sorghum and processed yam and cassava products

• Post-harvest Loss Network determined

losses for cereals to range between 17.4% to 14.3% (2003 till 2008)

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PICS bag trial

• Storage of 25 kg of maize variety QPM

in PICS bags and woven polypropylene bags as control

• HALF the bags artificially infested with

25 adults of P. truncatus

• Destructive sampling after 3 and 6

months

• Moisture content, insect species, grain

losses, holes on bags determined

• Cost/benefit analysis to determine

financial profitability PICS bag

Moisture content in PICS bags (PsB) and Polypropylene Bags (PPB)

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Means numbers of holes on PICS Bag (PsB) and PPB

Treatment 3 months 6 months PsB (natural) 0.75 ± 0.75 0.50 ± 0.50 PsB (artificial) 0.00 ± 0.00 1.25 ± 0.75 PPB (natural) 308.50 ± 36.39 322.25 ± 19.74 PPB (artificial) 344.25 ± 40.53 350.75 ± 25.38 PsB PPB

Effect of PICS Bag (PsB) on maize post-harvest pest after 3- and 6-month

Treatments Average density of insects /Kg

• P. truncatus
• S. zeamais
• C. quadricolis

Tribolium sp. 3 months of storage 6 months of storage 3 months of storage 6 months of storage 3 months of storage 6 months of storage 3 months of storage 6 months of storage PsB PPB (Control) 0.75 ± 0.38 Aa 0.62 ±0.27 Aa 0.30 ± 0.11 Aa 0.96 ± 0.12 Ba 2.47 ± 0.69 Aa 234.37 ± 33.28 Ba 1.35 ± 0.41 Aa 238.75 ± 2.38 Ba 0.00 ± 0.00 Aa 147.05 ± 7.82 Ba 0.00 ± 0.00 Aa 355.05 ± 14.26 Bb 0.00 ± 0.00 Aa 44.77 ± 5.18 Ba 0.00 ± 0.00 Aa 191.65 ± 6.83 Bb

• Both bags significantly reduced maize post-harvest insect

densities when compared to the control polypropylene Bags (PPB) (P = 0.018), except for P. truncatus after 3 months of storage (P > 0.05).

• While the pest densities remained statistically identical in PsB

and ISB, densities of C. quadricolis and Tribolium sp. increased significantly with sampling date (P <0.0001).

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Effect of PICS Bag (PsB) on maize post-harvest pest after 3- and 6-month

• Pest densities was significantly reduced in PsB compared to

PPB in 3- and 6-month storage period for S. zeamais, C. quadricollis and Tribolium spp. and 6-month storage period for

• P. truncatus (P = 0.018).
• Storage time did not affect insect densities in PsB (P = 0.111)

however, in control bag except for P. truncates and S. zeamais,

• C. quadricollis and Tribolium spp. densities increased

significantly with storage time (P < 0.0001).

• In PsB, P. truncatus was recorded during storage when maize

was artificially infested with this species whereas in PPB, it was recorded in all bags with no difference between artificial and natural infestation.

Effect of PICS Bag (PsB) on insect mortality.

Mortality rate (%) /Kg

• P. truncatus
• S. zeamais
• C. quadricolis

Tribolium sp. Treatments 3 months of storage 6 months of storage 3 months of storage 6 months of storage 3 months of storage 6 months

• f storage

3 months

• f storage

6 months

• f storage

PsB PPB (Control) 100 Aa 100 Aa 100 Aa 96.43 ± 2.33 Aa 95.83 ± 4.16 Aa 11.35 ± 1.71 Bb 100 Aa 34.05 ± 2.69 Ba

• 7.38

± 0.51 a

• 10.50

± 0.73 b

• 4.87

± 0.56 a

• 7.60

± 0.29 b

• In PsB 100 % mortality of P. truncatus was obtained during the

6 months of storage

• S. zeamais mortality was significantly lower in PPB than in PsB

at each sampling with 100% mortality in PsB after 6 months of storage.

• Mortality rate of C. quadricollis and Tribolium spp in PPB also

increased with storage time.

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Effects of PICS Bag (PsB) on maize grain losses after 3- and 6-months

• Losses were significantly lower in PsB .
• No increase of losses in PsB.
• In control bag losses increased significantly

with storage time reaching nearly 18%.

Treatments Months after storage 3 months 6 months PsB PPB 0.28±0.01 Aa 9.56± 0.34 Ba 0.31 ± 0.01 Aa 17.95± 0.51 Bb

Financial benefits of PICS

If bags would be reused for a second storage season the benefit/cost ratio would increase to 3.7, 5.0 and 6.3

Maize prices in three local markets Benefit Cost Ratio of the use of PICS bags

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What R&D is missing

• High moisture content of grains in PICS bags could reduce

germinability and lead to quality loss

• Need for low-cost energy efficient dryers to improve grain

drying

• Potentially increase effectiveness of PICS bags by including

another technology to reduce insect attack

• Test PICS bags for other

commodities and include further quality parameters

• All stakeholders need to

address the persistent high post-harvest losses

Acknowledgements

• PICS TEAM
• IITA
• NARS Partners
• Farmers Associations
• Women Associations
• Enumerators

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THANK YOU