Increasing value of African mango and cashew production


Start date: 1 January, 2011 End date: 31 December, 2015 Project type: Larger strategic projects (prior to 2013) Project code: 10-025AU Countries: Benin Tanzania Thematic areas: Agricultural production, Lead institution: Aarhus University (AU), Denmark Partner institutions: Charles Darwin University (CDU), Australia CIRAD, France/Germany Sokoine University of Agriculture (SUA), Tanzania University of Abomey-Calavi (UAC), Benin Policy Brief: Policy Brief Project coordinator: Jørgen Axelsen Total grant: 10,077,534 DKK Project files:

Project summary

Cashew and mango are high value crops ideal for export and important commodities in Sub-Saharan Africa (SSA). Yet production is severely affected by pests reducing yields and quality. Benin, for example, lost 42% of its mango value to fruit flies in 2006, hampering export earnings severely. Weaver ants protect several crops. This is applied in Integrated Pest Management (IPM) which has been successfully implemented in Australia and Asia. Here weaver ant IPM efficiency equals pesticide use in cashew and mango, is cheaper, locally available, sustainable and compatible with organic certification - without reduced yields. Preliminary studies show that weaver ant protection may increase African cashew production 4-5 fold and almost eliminate fruit fly problems in mango. The estimated economic value of this is $US 300 million per year in Benin and Tanzania. The project is expected to result in higher revenue to farmers, increased export earning via linkage to valuable export markets by adding organic certification to the value chain and protein availability via harvest of ant larvae. To obtain this, the price premiums that can be expected for organic cashew and mango in selected European markets will be investigated. Knowledge transfer to Africa will be integrated in building up research capacity on sustainable IPM in Benin and Tanzanian cashew/mango production at both the university and extension level to ensure sustainability and dissemination. Furthermore, the results may be used in other crops and countries.


Project Completion Report:
The results will be presented in relation to project objectives as required by DFC in mail from Bente Ilsøe on behalf of Research á 10. April 2014. Objectives are numbered.

1. Sixteen scientific papers have been produced to address this objective, and the results have clearly paved the road for introducing and optimizing weaver ant control as an IPM component in mango and cashew in Tanzania and Benin. Although these results are from two countries only it is very likely that the results also applies in other countries, meaning that Tanzania can be at stepping stone in East Africa and Benin in West Africa.

2. Ten scientific papers address this objective and they were mainly dealing with how to improve the performance of the weaver ants in biocontrol in mango and cashew. It was demonstrated that transplantations of larvae and pupae from other colonies, and feedingwith sugar and meat can boost weaver ant colony performance and thereby increase both fruit/nut yield and quality. This is done without the use of pesticides thereby allowing organic production.

3. One scientific paper, a PhD-thesis chapter, and yet unpublished work address this objective. The export barriers facing would-be exporters in both Benin and Tanzania have been identified and described.

Exports of mangos from Benin or Tanzania to Europe are very limited and there is hardly any local processing of fruits. Local processing faces logistical challenges due to poor infrastructure (lack of cold storage facilities, lack of refrigerated trucks and poor roads) and high transport costs due to lack of competition in container shipping from Africa to Europe. There is very little local processing of cashew, as most nuts are shipped to India for processing. This seems to be very difficult to break, as the Indian buyers have a firm grip of the entire marked.

Overall, European importers require production to meet European food safety standards – both regulatory requirements and private standards like BRC or GlobalG.A.P. However, African countries lack institutions that can support certification and monitoring of compliance. This makes it difficult for African firms to export to Europe.

4. The idea of harvesting weaver ant queens as a food source unfortunately had to be abandoned as the African weaver ants do not have a profound peak production of queens as they produce queens almost all around the year. Using the South-East Asian ant queen harvesting technique therefore did not give a sufficient yield of queens and queen larvae to be worth the effort.

5. The methods developed in the project have been thoroughly describer in the photobook´“Cashew and Mango Integrated Pest Management Using Weaver Ants as a Key Element. For organic cashew and mango growers in Africa” produced by Rengkang Peng, University of Darwin. The photobook is a very important output from the project and the African Partners have got electronic versions to distribute.

A course for farmers and extension workers were held in Tanzania, and a documentary on weaver ants technology was aired by the Tanzania Broadcasting

6. This objective was completed by the successful graduations of all seven PhD-students of the projects.

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