Evaluation of Yield Gap of Durum Wheat Genotypes Under Research and Farmer's Fields Conditions

Study of rainfed wheat production in Kermanshah province, Iran, during 1984-2013 indicates no clear trend in yield increasing, while rainfed wheat yield varied between 600 to 1400 kg/ha in this period. Assessment of attainable and actual yields, identify the yield gaps, limiting factors involved in achieving attainable yield and develop suitable strategies can help to improve yield productivity under rainfed conditions. In this study 12 wheat genotypes consisting of 9 durum wheat lines, one new durum wheat cultivar (cv. Saji) and two durum (Zardak) and bread (Sardari) local varieties were evaluated in a randomized complete blocks design with three replications in Sararood rainfed research station and three farmer's fields (i.e. Dalahoo, Sarfirouz abad and Homail) in Kermanshah province, Iran, during 2009-10 cropping season. Evaluation of genotypes based on mean yield indicated that the Saji cultivar produced higher yield than two local checks across four experimental sites, and out yielded the checks by 42 to 198%, depending on experimental sites. Some genotypes performed better than Saji cultivar across experimental sites (except Dalaho site), in which breeding line G8 performed better than Saji in two sites (Homail and Sararood) and others performed well in one site. Comparison of mean yield production in research station with farmer's fields indicated a decreasing yield equal to 35 to 80%, depending on experimental site, in farmer's fileds compared to research station. In regard to the results, development of cultivation of Saji durum wheat cultivar can be considered as one of the approaches to further enhance of yield productivity and to decrease of yield gap of rainfed wheat in Kermanshah province.