Grain yield of cereals such as maize in the highlands of northern Ethiopia is low mainly due to the low content of essential nutrients. Fertilizer application has commonly done by blanket recommendation of fertilizer rates without soil test and tissue analysis for a specific site. Use of fertilizers in Ethiopia is dominantly based on nitrogen (N) and phosphorus (P). The attention given to other essential nutrients such as sulfur (S) is practically none. The objective of this study was to evaluate the yield response of maize to different rates of N and S and recommend N and S fertilizers to maize production on Vertisols of Chilga District. The experiment was conducted during the 2008 growing season. The experimental design was laid out as two-factor experiment of three levels of S and four levels of N in Randomized Complete Block Design (RCBD) with three replications. The S rates were (0, 15 and 30 kg S ha-1 ) and four rates of N (0, 30, 60 and 90 kg N ha-1 ) and the test crop was hybrid maize of BH-540. The experimental site is low in its soil fertility status: slightly acidic (pH 6.5 ); clay in texture ( 23.3 % sand, 21.9 % silt and 54.8 % clay); high in CEC 65.3 cmol+/kg; soil organic carbon content of 1.4%; total N 0.09%; and available S 1.5 ppm. Nitrogen concentration of maize leaves was increased with increasing N rates. The results of the experiment showed that the maximum grain yield for the main effect N fertilizer was recorded in plots treated with 90 kg N ha-1 while for S fertilizer in plots treated with 15 kg S ha-1 . For fertilizers N and S interactions, the maximum grain yield and dry biomass were recorded on plots treated with the combination of 90 kg N with 15 kg S ha-1 rates which were significantly higher (p ≤ 0.05) than the control by 391.7 and 479.9%, respectively. This work showed that the yield response and nitrogen use efficiency (NUE) of maize crop were improved with N and S fertilizer applications that benefit the maize-producing farmers in soils deficient in these nutrients.
