Date of Award


Document Type

Open Access Master's Thesis

Degree Name

Master of Science in Biological Sciences (MS)

Administrative Home Department

Department of Biological Sciences

Advisor 1

Erika Hersch-Green

Committee Member 1

Molly Cavaleri

Committee Member 2

Casey Huckins


In Sub-Saharan African countries, soil fertility is low due to unsustainable agricultural practices and little to no access to chemical fertilizer. Poor yields have resulted in many of these countries struggling to produce enough food to feed their growing populations. Human urine has been used as an effective, low-cost alternative to chemical fertilizers in greenhouse and plot trials on a variety of vegetables, but its effects on elemental grain composition in cereal crops are largely unknown. Here we tested whether diluted human urine applied as a fertilizer can increase maize crop growth, yield and nutritional content on small family-owned plots. In Hagafilo village, in the Southern Highlands of Tanzania, participating farmers maintained family plots (n=8) within which half of the plot received urine fertilizer and water, while the other half received water only. The experiment ran for one growing season. We found that urine fertilizer significantly increased growth (above and below ground dry biomass, stem length) and yield (cob length, number of total and developed cobs) metrics. We also found that shoot/root ratio was greater in the control treatment, suggesting that the fertilized plants invested a greater proportion of resources into roots relative to shoots; this could have implications for soil health as extended root systems can minimize soil erosion and have longer term benefits on soil fertility. In contrast, urine fertilizer did not significantly alter maize kernel nutrients. An increase in grain nitrogen is usually observed with increases in fertilizer supplied. This study supports the use of human urine fertilizer as a way to increase food security.