Water Productivity of Teff under Semi-Arid Climates

Abstract

In the arid and semi-arid regions where the availability of irrigation water is a limiting factor for crop production, the knowledge of the water productivity of crops is imperative. Teff is a crop specific to Ethiopia where much of its properties are not duly studied. The purpose of this study was to systematically investigate teff’s response to moisture stress and to estimate its water productivity. This field experiment was conducted to investigate the effects of irrigation level on the performance and water productivity of teff. The experiment was laid out in randomized complete block design with three replications. The treatments considered were seven levels of water application (0.5 ETc, 0.6 ETc, 0.7 ETc, 0.8 ETc, 0.9 ETc, ETc and 1.25 ETc). Effects of irrigation levels on teff grain yield was highly significant (p < 0.01) whereas significant (p < 0.05) on biomass. The maximum teff grain yield (1053 kg/ha) and biomass (4267 kg/ha) were recorded from the 1.25 ETc experimental plots. But, a minimum yield (329 kg/ha) and biomass (2747 kg/ha) were recorded from the 0.5 Etc experimental plots. It was also observed that 50% reduction in the amount of irrigation water decreased the teff production in terms of grain yield and biomass by 69% and 36% respectively, while a 100% ETc water application decreased total teff grain and biomass by only 18% and 14%, respectively. A yield response factor (Ky) of 1.07 was determined. The water productivity for teff biomass ranged from 1.2 kg/m³ (for the 1.25 ETc) to 2.0 kg/m³ (for the 0.5 ETc).The water productivity for teff yield was the highest (0.34 kg/m³) at 0.7 Etc irrigation water application. The average height of the crop for the maximum (1.25 ETc) and minimum (0.5 ETc) irrigation water application were 54.6 and 85.9 cm, respectively. The harvest indices of teff for 1.25ETc and 0.5 ETc were found to be 12% and 25%, respectively. It is, therefore, concluded that the advantage of deficit irrigation is unlikely in teff grain yield production but advantageous in teff biomass.

Keywords: water productivity, teff, semiarid, deficit irrigation