Food Security

, Volume 6, Issue 3, pp 359–368 | Cite as

Application of the TOA-MD model to assess adoption potential of improved sweet potato technologies by rural poor farm households under climate change: the case of Kabale district in Uganda

  • John Ilukor
  • Fredrick Bagamba
  • Bernard Bashaasha
Original Paper


Sweet potato technologies that increase productivity, such as drought resistant varieties and virus free planting material are being promoted in order to reduce the vulnerability of poor farm households to climate change. In this paper, the Trade-off Analysis, Minimum Data Model Approach (TOA-MD) was used to assess the adoption potential of these technologies by resource poor farmers under climate change in Uganda. The model was calibrated and validated using household survey data collected in 2009 from Kabale district. To simulate adoption potential, the base system data was generated from household data and adjusted to reflect impact of climate change on crop yields and prices by 2050. The percentage increase in yields resulting from the use of climate resilient sweet potato technologies were used to estimate yields for alternative systems based on the results from sweet potato trials by the National Agricultural Research Organization (NARO), Uganda. Adoption potential of sweet potato technologies varied across altitudes. Compared with the high and lower altitudes, adoption potential is lowest at moderate altitude despite higher yields and lower costs of production. Paying farmers to adopt new sweet potato technologies is economically rational at the higher and moderate altitudes but not at the lower altitudes. The provision of free planting material (subsidy) for the evaluated technologies resulted in a modest increase of 2 % in adoption potential. Therefore, providing this as a way of increasing adoption of sweet potato technologies to reduce vulnerability of poor farm households to climate change will have a very small impact. Instead, climate change adaptation policy should focus on creating enabling environments for farmers to market their produce so as to raise returns and reduce the opportunity costs of climate change adaptation strategies.


Drought resistant varieties and Virus free planting material TOA-MD 



This work was part of a research project on participatory development and testing of strategies to reduce climate vulnerability of poor farm households in East Africa through innovations in potato and sweet potato technologies and enabling policies. It was implemented by Makerere University in collaboration with the International Potato Center (CIP) with funding from GIZ. We acknowledge Professor John Antle and Jetse Stoorvogel for training in the application of the TOA-MD model. We would also like to thank the two anonymous reviewers for their useful comments and for taking time to read our work.


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Copyright information

© Springer Science+Business Media Dordrecht and International Society for Plant Pathology 2014

Authors and Affiliations

  • John Ilukor
    • 1
    • 3
  • Fredrick Bagamba
    • 2
  • Bernard Bashaasha
    • 2
  1. 1.Makerere University Business SchoolKampalaUganda
  2. 2.Department of Agribusiness and Natural Resource EconomicsMakerere University, College of Agricultural SciencesKampalaUganda
  3. 3.Institute of Agricultural Economics and Social Sciences in the Tropics and SubtropicsUniversity of HohenheimStuttgartGermany

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