Building an Economically Sustainable Seed System for Cassava (BEST Cassava)

2017 - 2021 (Closed December 2021)

MEDA, the International Institute of Tropical Agriculture (IITA), the Tanzanian Agriculture Research Institute (TARI), and the Tanzania Official Seed Certification Institute (TOSCI) collaborated to establish a commercial cassava seed system in Tanzania for smallholder farmers. The aim of this project was to support smallholder farmers with timely access to affordable, quality-assured, disease-resistant, and higher-yielding cassava seed varieties.



BEST Cassava stands for Building an Economically Sustainable Seed System for Cassava in Tanzania. The BEST Cassava project was implemented in 11 regions across three zones (Lake, Eastern, and Southern Zone) to benefit smallholder farmers and their households.


The overall goal of the BEST Cassava project was to increase the agricultural productivity and incomes of smallholder cassava farmers through access to improved cassava seed. The use of superior cassava seed varieties by cassava farmers supported the production of high-yielding cassava despite the continued presence of crop diseases.


BEST Cassava supported the creation of over 430 Cassava Seed Entrepreneur businesses that sold quality-assured, disease-resistant and higher-yielding cassava seed varieties to over 29,000 smallholder farmers over the life of the project.


Cassava is a vital crop for millions of smallholder farmers in Tanzania. Cassava has been transitioning from a staple crop to a commercial crop, generating economically sustainable livelihoods for farmers and is therefore increasingly crucial for agricultural sector transformation. The Lake, Southern, and Eastern Zones are major cassava growing regions in Tanzania whose farmers have experienced low yielding varieties, viral crop disease outbreaks and the use of less efficient agricultural practices.


The presence of pests and crop diseases provides great challenges for farmers and entrepreneurs. Yet, these challenges create opportunities to build a commercial supply of improved, higher-yielding, virus-free seeds so farmers can invest in more profitable and reliable cassava farms.


The BEST Cassava project worked to create an affordable and accessible commercialized cassava seed system for growing quality-assured planting material of improved, disease-resistant varieties while boosting the incomes of smallholder farmers. This was achieved by:

  • An increased use of cost-effective, disease-resistant cassava varieties preferred by smallholder farmers and other commercial seed supply chain stakeholders
  • Strengthening government institutions that collaborated with the private sector. Through this collaboration, it provided an environment for growing seed delivery from research to farmers and established guidelines for quality certification
  • An increased private sector capacity to develop a vibrant cassava seed supply chain


MEDA’s Senior Director, Global Program Operations, David Eagle, and MEDA’s Tanzania Country Project Manager, Stephen Magige have contributed to a chapter in the Agricultural Science book, “Root, Tuber and Banana Food System Innovations – Value Creation for Inclusive Outcomes.” Together with other industry experts and partners, they co-wrote Chapter 15, “Commercially Sustainable Cassava Seed Systems in Africa” which outlined how building strong Cassava seed systems creates value for Cassava seed entrepreneurs and their value chains.

Our Cumulative Impact by FY2021 (Project Closing Year)


Direct Individuals


Direct Businesses


Direct Women Clients


% Direct Youth Clients


Indirect Individuals


Indirect Businesses


Decent Work


Total Budget


This project was undertaken with the financial support of the Bill & Melinda Gates Foundation.