Development and Evaluation of Locally-Made Fertilizers in Ethiopia.

Few Ethiopian farmers purchase urea and di-ammonium phosphate fertilizers available through agricultural cooperatives.  Fertilizer usage rates are negatively correlated with distance from a paved road due to very high transportation costs.  Therefore, the goal of our work is to make fertilizers from locally-available materials, thus reducing the costs due to importation and transportation and leading to improved soil fertility and enhanced crop yields.  Ethiopia is the country with the highest livestock population in Africa.  Livestock are slaughtered in villages and cities, and bone piles are left behind unused.  We collected bones, ground them to two different fineness levels, and acidified them using coffee wastewater.  Then we compared this bone-based P fertilizer to commercially-available P fertilizer in a greenhouse experiment using maize and common bean.  Secondly, we cultured cyanobacteria from Ethiopian soils and grew them in shallow raceways.  Cyanobacteria use the Sun’s energy through photosynthesis to drive the N fixation process.  Then the cyanobacteria were harvested in either liquid form (~0.003 % N) or in solid form (~6% N) and compared to urea in greenhouse trials growing maize, kale, pepper, lettuce, and tomato.  Results from these studies are promising and provide alternatives to imported, expensive, fertilizers that depend on limited resources such as rock phosphate and fossil fuels.