A full-diallel cross of five durum wheat genotypes[Simeto (1), Ofanto (2), Acsad 65 (3), Miman-9 (4) and CRAK-10 (5)] was made in the growing season 2010-2011 at the Research Field of the College of Agriculture, Salahaddin University in Erbil, Iraq. Grains of 20 F1s and their five parents were planted on 15 November 2011 in two separate experiments, rainfall (stress) and irrigated (nonstress) using a randomized complete block design with three replications in order to study the genetic properties of days to flowering, plant height, flag leaf area, spike length, no. of spikes/plant, no. of grains/spike, 1000-grain weight, biomass yield/plant, grain yield/plant and harvest index by using Griffing, Hayman and Jinks-Hayman approaches. The results revealed that some parents exhibited positive and high general combining ability, while some hybrids showed specific combining ability for the majority of these traits. Important role of additive genetic component (D) was found for days to flowering, flag leaf area spike length, no. of spikes/plant, no. of grains/spike and biomass yield/plant under stress conditions and days to flowering, spike length, no. of spikes/plant, 1000-grain weight, biomass yield/plant, grain yield/plant and harvest index under non-stress conditions.The non-additive component (H1) was found to be important for the genetic control of all the traits under stress and non-stress conditions excluding grain yield/plant under stress conditions. The average degree of dominance (H1/D) ½ was>1 for all traits in both cases. The narrow sense heritability H n.s . was low for flag leaf area, moderate for no. of grains/spike and 1000-grain weight, high for remaining traits under stress conditions. While low for no. of grains/spike, moderate for days to flowering, flag leaf area and grain yield/plant, high for remaining traits under non-stress conditions.Under stress conditions high heterosis was exhibited by cross [1×4] for most traitswhile by cross [5×3]under non-stress conditions.It could be concluded that generated of these genotypes will serve for the breeders to develop high yielding of durum wheat under water stress und non-stress conditions by employing individual or mass selection breeding.

Two field experiments were carried out during the 2009-2010 growing season at the station of Directorate of Agricultural Researches/Erbil under dry farming conditions. The first experiment included 25 strains of durum wheat, and the second included 20 strains of bread wheat. Growth trait, yield and its components were studied, and then data are entered in the statistical genetic analysis, as well as the path coefficient analysis. The results showed high genetic variation, heritability and genetic advance for plant height, number of spikes, 1000 grain weight, biological yield and grain yield in durum wheat. While it was high in all traits in bread wheat. The grain yield was correlated genetically positive and significantly with 1000 grain weight, biological yield and harvest index in durum wheat, while showed genetically positive and significant correlation with all traits in bread wheat. The path coefficient analysis revealed that harvest index and biological yield had the maximum positive direct effects on grain yield in durum wheat reached 0.966 and 0.242, respectively. While the harvest index had the maximum positive direct effect (1.417) on grain yield in bread wheat, which was used as a criterion for the selection of superior genotypes in each group.

This study was conducted during the spring season of 2008 at the Farm of the College of Agriculture -Duhok University, Iraq by using five maize inbred lines locally developed. Half diallel cross design was applied for these inbred lines to produce ten F 1 single crosses. A yield trial for the 10 hybrids and their parents was carried out in the Research Farm of the College of Agriculture Salahaddin University, Iraq using a randomized complete block design with three replications in order to study the gene action for yield and yield components beside estimating heterosis, combining ability and variance components (additive, dominance and environmental variance) in addition to estimate some other genetic parameters. The results showed the presence of significant differences among genotypes for all characters. For mean grain yield the best parent was (ZP -197), while the best hybrid was (ZP -707 × DK). The parent (ZP -595) appeared to be the best general combiner for most studied characters, while the hybrid (ZP -607) × (ZP -707) appeared to be the best for specific combining ability. Ratio of general to specific combining ability variances was more than one for all characters, indicating that the characters were under the effect of over dominance. Broad sense heritability value was found to be high in all the studied characters, while the narrow sense heritability was moderate for silking and tasselling date, grain yield / plant, number of kernels / row , 100-kernel weight and low for plant height , ear height , leaf area , number of rows / ear, ear length and number of kernels / ear. The expected genetic advance from selection was high for grain yield / plant and 100-kernel weight. The hybrids (DK × ZP-197) and (ZP -707 × ZP -197) gave the highest heterosis value in silking and tasselling date, while the heterosis value was high for the flag leaf area, ear height and grain yield / plant and was low for kernels / row , rows / ear, ear length and 100-kernel weight with different hybrids.

In a factorial experiment using RCDB design with three replications carried out at the College of Agriculture at the University of Dohuk in Semail during the two seasons (1994-93, 1996-95) it included a study of the effect of two methods of cultivation (scattering and in lines) and four rates of seeding (30, 60, 90, 120 kg/ha) depends on the growth and yield of locally grown lentils. The results showed that the local lentil responded to an increase in the seeding rate to 120 kg/ha, and this had a positive effect on the yield. Seeds and the two methods of cultivation and in the two seasons.

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/m 2 , which had the greatest effect in the prediction of grain yield according to the results of multiple regression analysis.