Human urine as a low cost and effective nitrogen fertilizer for bean production

Abstract

The overuse and misuse of chemical fertilizers attributed to critical environmental and health problems such as Chronic Kidney Disease (CKD) in Sri Lanka. Therefore, there is a growing trend among present researches to explore low cost, effective fertilizer substitutes for inorgnaic fertilizers in cropproduction. Human urine is a liquid waste rich in essential plant nutrients such as nitrogen, phosphorous and potassium. This study was conducted to explorethe possibility of utilizing human urine in edible crop production as a low cost and effective nitrogen fertilizer.The study was conducted in a greenhouse using bushita bean (Phaseolus vulgaris L.) as crop species. Five treatments: T1 (Albert solution), T2 (Agriculture department recommendation for nitrogen (N), phosphorous (P), potassium (K) fertilizers; Urea, TSP and MOP), T3 (Human urine; nitrogen concentration adjusted to 20% less than the nitrogen concentration in T2), T4 (Human urine; nitrogen concentration adjusted similar to T2), and T5 (human urine; nitrogen concentration adjusted to 20% more than the concentration in T2) were applied three weeks after planting. Results revealed that T5 showed the highest increase in plant height, leaf area, root dry weight and total nitrogen content of leaves. Bean yield was significantly higher (p<0.05) in plants received T1 and T2 compared to urine-fertilized treatments. Even though, bean yields of urine-fertilized treatments (T1, T2 and T3) not directly comparable to that in the industrial-fertilized treatments (T1 and T2) were at a satisfactory level. The urine treatments were more cost effective than T1 and T2. Based on the results, we suggest that urine can effectively be used as a nitrogen fertilizer substitute in agricultural production.