1. A commodity system analysis to reduce post harvest losses of vegetable
Realized by:
KODJOGBE Guy, Chantal Pali, Nana Fredua AGYEMAN, Marian ASAMOAH,Christophe Kouame, Benoit Gnonlonfin, Kerstin HELL, Ousmane COULIBALY

2. Background
Fresh vegetables production provides employment for nearly 60,000 people in Benin (PADAPA, 2003)
It was estimated that between 30 and 40% are produced for own consumption (Hounkpodote and Tossou, 2001)
In Kumasi (Ghana), 37 percent of the population reported farming as their main occupation, and this is particularly so for women (Brook and Davila, in Gundel, 2006)

3. Background
Fresh fruit and vegetables production is confronted with a lot of difficulties: 
- the ownership problem
- lack of technical training for producers
- poor access to credit and inputs
- distribution and marketing difficulties
- the high competition between local products and imported products (Deguenon, ).
High losses have been reported for African countries ranging between 15%–30% of the harvested product (Buys and Nortje, 1997)

4. Objectives of study
Post harvest losses (physical and economic) assessment on tomato, fresh pepper, dried pepper, lettuce and okra
Identification of post harvest losses causes and destinations.
Identification of mycoflora which accelerate the fresh vegetables losses

5. Methodology
4 methods are applied in order to assess post harvest losses on these vegetables value chains.
Benin
Ghana
Product
Tomato, Lettuce, fresh pepper
Tomato, Lettuce, fresh pepper, dried pepper and Okra
Study zone
Grand-Popo, Cotonou, Porto-Novo
Accra
Focus group
Inventory problems occur by producers: (1group/zone) and traders (3groups/zone)
Survey
Losses (physical and economic), causes and destinations according producers (60) and traders (180) perceptions
Losses (phisical and economic), causes and destinations according producers (60) and traders (180) perceptions
Laboratory analysis
Dilution method (speck, 1976): 30 samples/product/zone
Tracking samples
Recording (morning, noon and afternoon)temperature under shed and temperature inside the baskets daily weighting and counting the samples

6. Methodology Tracking samples:
- Assess post harvest losses both quantitatively and qualitatively according to exposition temperature at market
- 6 baskets per product (1.5 kg) are chosen per trader (6)
- We have recorded the temperature under the shed and and the temperature inside the baskets at regular intervals time during morning, noon and afternoon.
- Daily, we have weighted the baskets and have counted the number of spoiled products;
- This method is applied during 5 days for tomato, 7 days for chilli pepper and 3 days for lettuce according to their traders purchase frequencies.

7. Methodology
Quantitative losses = Quantity of harvested or bought products – Sold quantity of products
Qualitative losses depend on product grade, the storage time and price.

8. Results and discussion
Focus group
Actors
Problems (in order of importance
Desirable solutions
Producers
1- Lack of irrigation
infrastructures
2- Poor access to markets/high competition of imported products
3- Lack/insufficient access to credit
4- Poor access to treatment chemicals and seeds
5- Insects and nematodes
6- Lack of skilled workers (training)
7- Transport and storage
1- Implementation of performed infrastructures for irrigation
2- Credit
3- Proximity and availability of treatment chemicals and seeds
4- Well trained workers
Traders
1- Poor access to credit
2- Poor access to markets
3- Lack of traders association
4- Transport and storage
5- Insects and fungi
1- Access to credit
2- Training for producers on use of inputs (fertilizers and pesticides)

9. Results and discussion
Table 1: Producers education level, training and association membership in Benin
Crops
Effectif
total
Education
Education level
Training
Association
Yes no
primary
secondary
High school
yes
Tomato 20
80%
20%
35%
30%
10%
55%
45%
40%
60%
Chilli pepper
75%
25% 5%
70%
65%
Lettuce
90%
50% 0%

10. Results and discussion
Table 2: Distribution of producers by education level, training and
association membership in Ghana
Effectif total
Education
Education level
Training
Association
Yes No
Primary
Secondary
High school 45
95.6%
4.4%
27.4%
60%
1.1%
37.8%
62.2%
100%

11. Results and discussion
Causes of post-harvest losses of fresh vegetables in those countries:
- use of local or auto-propagated seeds
- excessive use of fertilizer,
- poor irrigation system
- poor harvesting practices,
- supply exceeding demand
- Handling: poor transport and storage
- Insects and fungi

13. Results and discussion
Grade 1
firm and fresh; infestation rate<=5%; red-green (tomato and chilli), green (lettuce), Too expensive according to the seasons.
Grade 2
Less firm and less fresh; infestation rate between 15% and 20%; red (tomato and chilli), green with infestation (lettuce is throw away); the selling price fall gradually.

14. Results and discussion
Grade 3
poor quality; infestation rate >= 50%; red (tomato and chilli); discount and sold to street food traders
Grade 4
very poor quality; infestation rate = 100%; red (only the tomato); very discount and sold to street food traders

15. Results and discussion
Destinations of the post harvest losses:
- Spoiled products are left on the field and sold to street food vendors (more common)
- Seeds from spoiled products can be used for the next season
- Spoiled lettuce are given to pigs or sold to breeders

16. Results and discussion
Table 3 : Quantitative losses assessment in value chain (%)
Countries
Products
Collectors
Wholesalers
Retailers
/wholesalers
/retailers
Benin
Tomato 12 8 10 20 13
fresh pepper - 4
Lettuce 22 9 16
Ghana 2
45,62
39,75
Fresh pepper
1.07
1.51
0.92
Dried pepper
32.07
37.22
31.75
31.63
31.94
Okra
5.28
17.86
22.3

17. Results and discussion
Table 7: Mycoflora occurrence on vegetables (CFU/g) in Benin
Fungi
Products
Grand-Popo&Come
Porto-Novo&Cotonou
Aspergillus niger
Chilli pepper
Lettuce
Tomato
98.33 ± -
2.22± 16.61 ±
26.67 ±
Aspergillus flavus
91.95 ±
1.67 ± 15.81
56.06 ±
Rhizopus. stolonifer
2.27 ± 10.47
21.11 ±
Fusarium. verticilloides ± ± ±
Fusarium. prolifératum
68.33 ±
34.44 ±
96.11±
Fusarium. oxysporum
2.25 ± 21.20
Penicillium. citrinum
48.31 ± ±
45.00 ± 99.45
Penicillium. commune
2.22 ±

18. Results and discussion
Table 8: Mycoflora occurrence on vegetables (CFU/g) in Accra (Ghana)
Products
Aspergillus flavus
Aspergillus niger
Aspergillus ochraceus
Aspergillus penicilloides
Fusarium verticilloides
Fusarium proliferatum
Penicillium citrinum
Penicillium spp
Fresh pepper
108.56±30.023
91.44±16.048
17.47±7.119
11.3±5.766
0.34±0.342
Dried pepper
30.56±13.255
27.78±8.320
23.61±14.704
80.56±24.257
1.39±1.389
Tomato
8.33±7.448
3.7±2.594
27.78±15.787
8.33±8.333
2.78±2.055
Lettuce
2.00±2.000
87.33±22.079
86.67±20.910
13.51±8.458
21.33±6.790
1.33±0.936
Okra
0.41±0.407
84.15±14.956
42.28±15.185
72.36±15.437
54.88±14.203
0.81±0.573

19. Results and discussion
Tracking samples : tomato case
Tomato baskets weight and percent of spoiled tomatoes depend on display temperature

20. Conclusions
Post harvest losses are highest for tomato and lettuce, it can reach up to 20% after 5 days
Chilli pepper and okra are the fresh vegetable which are most infected by fungi in both countries: risk of mycotoxicosis
The main perceived causes of post harvest losses have their root at producer level:
- use of local seeds/ auto-propagated seeds
- excessive use of fertilizers and pesticides: pesticide residues
- poor harvesting practices
Poor handling (practices, packaging, etc.) cause losses during transport and storage

21. Suggestions
Improved access to high quality seeds (variety shelf life) and other inputs
Training of producers on appropriate use of fertilizers and pesticides, the appropriate marketing and production planning methods
Improved transport practices, packaging technologies (eg: using folding plastic boxes), improved storage infrastructures
Improved access to credit and improved providing policy makers subsidies to producers
Training traders on effective and efficient transport or storage practices
Monitoring of mycotoxins and pesticides residues