
Stem rust caused by Puccinia graminis f.sp. tritici is one of the major biotic constraints of wheat production. For controlling this pathogen fungicide application mandatory in Ethiopia but appropriate spray schedules is not well known and farmers were applying at least three times to control the stem rust disease. Hence the current research was designed with the objectives to evaluate the effect of fungicide spray schedule on stem rust development and grain physical quality of durum wheat. For this purpose, a factorial field experiment involving six durum wheat varieties (Denbi, Hitosa, Tob.66, Mukiye, Ude and Mengudo) with different level of resistance to stem rust, and three Tilt spray schedules of Tilt®250 E.C at 7, 14 and 21 days interval was conducted at Debre Zeit Agricultural Research Centre during the main and off seasons of 2016/17. The experiment was laid out in randomized complete block design with three replications and untreated checks were included for comparison purpose. Results revealed significant variations in disease parameters and crop performance among spray schedules, wheat varieties and their interactions. Stem rust severity was significantly reduced by the application of Tilt across all wheat varieties, and the highest decrease in disease level (8.9 and 15.2%) was achieved by Tilt sprays at seventh day interval during off and main seasons, respectively. By reducing the stem rust severity, it was possible to improve yield and grain physical quality of the produce. Current results demonstrate the need for effective and sustainable stem rust management to improve the grain physical quality of durum wheat in Ethiopia.