Abstract

Field experiments were conducted in 2017/18 cropping season at Kulumsa Research Center Farm (OnS) and on farmer’s (OnF) field to assess the effect of N fertilizer rates on grain quality and NUE of bread wheat (Lemu and Wane) varieties. Factorial combinations of Lemu and Wane varieties and five N rates (0, 46, 92,138 and 184 kg N ha-1) were laid out in a randomized complete block design with three replications. The results showed that Lemu variety had higher values of hectoliter weight and grain protein content (GPC) at both sites, while Wane variety exhibited greater values for dry and wet gluten content. Average GPC was 11% at OnF, while it was 14% at OnS. Grain and straw N uptake increased with increasing N rates, although increments were inconsistent. The NHI was highest when N was applied at 46 and 92 kg N ha-1at OnF and OnS, respectively. The GPC was improved by 12 and 15.1% when 138 and 184 kg N ha-1 applied at OnF and OnS, respectively. The highest wheat agronomic and physiological efficiencies were recorded when 46 kg N ha-1was applied in both sites. In nutshell, we recommend 46-92 kg N ha-1 for bread wheat production based on better grain quality, NUE and NHI in the highlands of Arsi, southeastern Ethiopia.

Key words: Bread wheat varieties, grain quality, nitrogen use efficiency, nitrogen uptake.