Effects of Nitrogen Fertilizer Rate and Inter-row Spacing on Yield and Yield Components of Teff [Eragrostis teff (Zucc.) Trotter] in Limo District, Southern Ethiopia

Teff [Eragrostis tef (Zucc.) Trotter] is the main staple food of Ethiopia. It ranks the first among cereals in the country in area coverage and second in the production volume; however, its productivity is almost stagnant. The Quncho (Dz-Cr-387) teff variety was sown during the main cropping season of 2017 at the Limo District, Southern Ethiopia. The objective of this research was to study the effect of four nitrogen fertilizer rates (0, 32.5, 65 and 97.5 kg N/ha) and three inter-row spacings (15, 20 and 25 cm), to evaluate the effects on yield and yield components of teff and to identify the economically appropriate nitrogen rates and inter-row spacing that maximize the yield of teff. A factorial experiment was laid out in Randomized Complete Block Design (RCBD) with 12 treatment combinations and three replications. Phenological and yield-related parameters were measured. The main effects of N rate and inter-row spacing showed significant differences (P≤0.05) for all yield and yield components. The effects of N rate by inter-row spacing interaction were not significant for some traits except for the lodging index, biomass yield, grain yield, and straw yield and harvest index. Application of N rate at 97.5 kg/ha and inter-row spacing with 25 cm significantly (P≤0.01) increased grain yield of teff. Moreover, both N fertilizer rates and wider inter-row spacing increased the magnitudes of the important yield attributes including plant height, panicle length, number of effective tillers per plant, thousand seed weight, biomass yield and straw yield significantly (P≤0.01) and also inter-row spacing increased the magnitudes of important yield attributes significance (P≤0.05). From the results of the study, it is possible to conclude that increased application of nitrogen fertilizer rate and row spacing improves yield and yield components of teff. Therefore, the application of 97.5 kg N/ha and inter-row spacing of 25 cm gave maximum yield which can be recommended for the study area.