Map of Africa with the 13 participating Sub-Saharan countries in brown.
Optimizing Fertilizer Recommendations in Africa
Optimized Fertilizer Recommendations in Africa (OFRA) enables farmers of Sub-Saharan Africa to maximize profit on fertilizer investments while increasing yield, maintaining or improving soil fertility, and protecting the environment. The OFRA project formed a network of research and extension teams from 13 countries with financial support from the University of Nebraska–Lincoln and the Alliance for a Green Revolution in Africa, managed by CABI-Nairobi, and with funding from the Bill and Melinda Gates Foundation.
Crop-nutrient response functions were determined for all important annual food crops of 67 agroecological zones (AEZs) using results of field research standardized and compiled in the OFRA Crop Nutrient Dataset consisting of >6000 crop-nutrient response functions with citations. Each AEZ’s fertilizer recommendations are developed using research results from similar crop growing conditions as in the AEZ (i.e. the AEZ’s inference space).* Crop-nutrient response functions were entered into the AEZ’s Excel fertilizer optimization tool (FOT). The FOT then uses linear optimization to re-iteratively work across the numerous crop-nutrient response functions to give fertilizer use recommendations in consideration of the farmer’s choice of crops and land allocation, fertilizer costs, grain values, and the farmer’s budget constraint to fertilizer use. Paper FOTs were also developed for each AEZ for use when computers are not available to advise the fertilizer product and rate, the time and method of application, and the farmer calibration of application to achieve a uniform application at the correct rate.
Resources developed by OFRA are freely available through the International Fertilizer Development Center http:ifdc.org/resources/ofra:
- the AEZ’s Excel fertilizer optimization tools
- the AEZ Paper fertilizer optimization tools
- Extension audio-visual training materials
- Fertilizer use calibration tools
- The 17 chapters of the OFRA book “Fertilizer Use Optimization
- in Sub-Saharan Africa” edited by Charles Wortmann and Keith Sones, 2017 CAB International publication. ISBN (hardcopy): 978 1 78639 204 6 and ISBN (e-book): 978 1 78639 205 3.
- OFRA Response Function Data Set
- Agricultural Ecozone Maps
- Publications
