Effect of rate and timing of Nitrogen Fertilizer on Sorghum Grain Yield and Yield Related Components

Abstract

The effect of timing and rate of nitrogen (N) fertiliser on the yield and yield components of sorghum was studied at Gumara-Maksegnit watershed, Gondar Zuria woreda, Amhara Region, Ethiopia, with a budget support of ICARDA. In the study area the amount of annual rainfall ranges from 995 to 1175 mm, however; more than 70% of the rain falls within three months (from June to August). In the study area sorghum is growing from long time and it gains much attention by the local people since it has different advantages like for food, for drink and the stovers for animal feed. However, the farmers have failed to give appropriate management for sorghum including input supply. As a result farmers obtained low yield of sorghum not more than 1 tone/ha. Therefore, the experiment was done to improve yield of sorghum by determining rate and application time of N fertilizer. The experiment was evaluated by the local people and experts during different farmers’ field days prepared by GARC, and farmers were encouraged and promised to give appropriate agronomic practices for their sorghum field. The experiment was laid out in randomized block design (RCBD) and investigated in the main cropping season of the year 2013 and 2014 at farmer’s field. There were three rates and three application time of N fertilizer and a control (without N fertilizer application), N rates are 41, 64 and 87 kg/ha and with application time of full application at, half at planting, have at knee height, and full application at knee height. The 46 kg/ha P2O5 fertilizer was applied to each plot at planting. All the necessary agronomic practices such as weeding, pest control, row plating, tinning were applied equally for each plot. Data were analysed for variance and LSD at 5% level of significance. The result revealed that N fertilizer application and timing had significant improved sorghum yield from 1t to 3.7 t per ha. This maximum yield was obtained at application of 87 kg/ha N in two splits. Therefore, it is concluded that split application of N fertilizer is necessary to improve sorghum yield in the Gummar-Maksgnit watershed. Further research should be done on the dissemination of the technologies to farmers.