Abstract
Maize productivity has been increasing through the years due to increased use of inorganic fertilizers. However, the price and environmental impact has brought lack of interest among the farmers. Thus, this study was aimed at evaluating the growth, yield and nitrogen use efficiency (NUE) of maize varieties under cattle urine application. The field experiment was conducted in randomized complete block design with three replications. The experiment consisted of four treatments viz. Control, 100 and 50 % cattle urine and recommended dose of inorganic fertilizer. The results demonstrated a comparable growth and grain yield increment due to 100 % cattle urine and recommended dose of inorganic fertilizer. The difference between the two varieties in growth, yield and related traits, and NUE indices due to fertilizer applications was non-significant. The leaf area of maize nourished with 100, 50 % cattle urine and recommended dose of inorganic fertilizer increased by 11.15, 9.73 and 9.78 folds, respectively, in two months period relative to the controls. Fertilized plants had significantly (p < 0.05) higher grain yield (GY). The use of 100, 50 % cattle urine and inorganic fertilizers resulted in 526.76, 326.12, 542.91 % and 47.83, 36.03, 49.78 % increment in average GY and aboveground biomass, respectively, compared to controls. Similarly, plants fertilized with 50 % cattle urine showed an average GY reduction of 39.87 and 38.10 % compared to the recommended dose of inorganic fertilizer and 100 % cattle urine, respectively. The use of 50 % cattle urine produced significantly higher NUE, N agronomic efficiency (NAE), N recovery efficiency (NRE) and internal efficiency (IE). Higher GY kg(-1) of N applied was obtained from cattle urine applications. In a nutshell, the results confirmed the potential of cattle urine as an alternative to inorganic fertilizers in maize production. However, further studies on optimization of the cattle urine rate and scale up works are recommended.