Effect of Different Nitrogen Fertilizer Rates on Yield and Yield Related Traits for Seven Durum Wheat (Triticum turgidum L. var Durum) Cultivars Grown at Sinana, South Eastern Ethiopia

An experiment was conducted at Sinana district on farmers field to study the effects of different nitrogen fertilizer rates (0 = control, 23, 46 and 69 kg ha-1) on crop phenology, yield and yield related traits, nitrogen uptake parameters and grain protein content of seven durum wheat cultivars (Ude, CDSS93Y107, Ejersa, Bekelcha, CD94523, Cocorit71 and Inglize). The experimental site soil samples were analyzed and texture was clay, with organic matter of 4.5%, available P of 8.8 ppm, CEC of 27 cmol kg-1 and pH of 7.1 and total nitrogen content of 0.24%. The experiment was conducted in a Randomized Complete Block Design (RCBD) with three replications. The result showed that nitrogen rates and cultivars had significant effect on yield, yield related traits, nitrogen uptake parameters and protein content. The cultivars CD94523 (4989 kg ha-1), CDSS93Y107 (4923 kg ha-1) and Bekelcha (4605 kg ha-1) showed better grain yield performance at the highest rate of nitrogen (69 kg ha-1) application probably due to highest response of the cultivars and use efficiency to N fertilizer. At 46 kg ha-1 N rate application, cultivars (Ude, Ejersa, Cocorit 71 and Inglize) showed also high grain yield similar to grain yield of 69 kg ha-1 N application. The TKW and HLW of the cultivars were ranged 42.5-49.5 g and 78.5-81.6 kg hL-1, respectively. Among cultivars, Ude and Bekelcha were superior for TKW. The HLW of Ude, CDSS93Y107, Ejersa and Bekelcha were significantly superior. Increased N rates up to 69 kg ha-1 had increased straw N uptake, grain N uptake and total N uptake and the lowest N uptake was for the control treatment. The grain protein content (12.5%, mb) had ranged from 10.2% (Inglize) to 13.4% (Ude, Ejersa and Bekelcha) (P > 0.05). The highest N rates resulted in 15% more grain protein content than the control treatment which is essential for pasta processing and better nutritional value.