Abstract
This study was carried out in the field of College of Agriculture - University of Salahaddin in Erbil during the season 2009 - 2010 including the evaluation of four hybrids derived from diallel crosses among seven varieties of durum wheat, previously assessed on the basis of combining ability and heterosis of them. The breeding program continued until these hybrids reached the sixth generation, and were compared with three other varieties, two of them cultivated on a large scale. Fifteen traits were studied, including different growth, physiological characters and grain yield and its components. The hybrid (Acsad- 65 × Kosem- N) has been selected to continue its breeding in order to adopt a new variety based on its performance superior in most of the studied traits, especially in the productivity score and grain yield and in traits that are showed positive correlation with the grain yield like leaf area index, net assimilation rate, spike length, 1000-grain weight and spikes/m2, which had the greatest effect in the prediction of grain yield according to the results of multiple regression analysis.