Effects of Blended NPSB and N Fertilizer Rates on Maize (<i>Zea mays</i> L.) Grain Yield and Yield Components in Chora District, Buno Bedele Zone, South Western Ethiopia

Abstract

Maize is a significant cereal crop in Ethiopia. However, the yield of this crop is declined from time to time due to continuous use of DAP and urea for a long season, which resulted in deficiency of other important nutrients and due to absence of the right fertilizer with the right rate at the right time. Therefore, a field experiment was conducted at chora district during the 2021 main cropping season to assess the effect of blended NPSB fertilizer rates supplemented with inorganic N fertilizer on maize grain yield and yield components and to determine the economically optimum levels of blended NPSB and N required to give higher yield of maize. The treatment consisted of factorial combination of five levels of blended NPSB (0, 50, 100, 150 and 200kg/ha) and four levels of N (0, 23, 46 and 69kg/ha) fertilizer rates. The experiment was laid out in randomized complete block design (RCBD) with three replications. Analysis of the results revealed that, plant height (PH), above ground dry biomass (AGDB kg/ha), grain yield (GY kg/ha) and stalk yield (SY kg/ha) were highly significantly affected by main effect of blended NPSB and N rates, as well as by their interaction, while number of cob per plot (NCPP), cob length (CL), number of grains per cob (NGPC), thousand kernel weight (TKW gm) and harvest index (HI%) were significantly affected by main effect of blended NPSB and N rates, as well as by their interaction. Only number of rows per cob (NRPC) was not significantly affected by both main effects of blended NPSB and N rates, as well as their interaction. The result showed that, the highest grain yield (7026.4kg/ha) and net benefit (89020 ETB/ha) with an acceptable marginal rate of return (1010.9%) was obtained from the plot treated with 200kg/ha of NPSB and 69kg/ha of N fertilizer rates. Therefore, based on the result obtained from this study, application of 200kg/ha of blended fertilizer supplemented with 69 kg/ha of N fertilizer can be suggested as profitable for production of maize at the study area and their similar soil conditions and agro-ecologies.