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Öğe Genetic gains in wheat in Turkey: Winter wheat for dryland conditions(ELSEVIER SCIENCE BV, 2017) Keser, Mesut; Gummadov, Nurberdy; Akin, Beyhan; Belen, Savas; Mert, Zafer; Taner, Seyfi; Topal, AliWheat breeders in Turkey have been developing newvarieties since the 1920s, but fewstudies have evaluated the rates of genetic improvement. This study determined wheat genetic gains by evaluating 22 winter/facultative varieties released for rainfed conditions between 1931 and 2006. The studywas conducted at three locations in Turkey during 2008-2012, with a total of 21 test sites. The experimental design was a randomized complete block with four replicates in 2008 and 2009 and three replicates in 2010-2012. Regression analysis was conducted to determine genetic progress over time. Mean yield across all 21 locations was 3.34 t ha(-1), but varied from 1.11 t ha(-1) to 6.02 t ha(-1) and was highly affected by moisture stress. Annual genetic gain was 0.50% compared to Ak-702, or 0.30% compared to the firstmodern landmark varieties. The genetic gains in drought-affected sites were 0.75% compared to Ak-702 and 0.66% compared to the landmark varieties. Modern varieties had both improved yield potential and tolerance to moisture stress. Rht genes and rye translocations were largely absent in the varieties studied. The number of spikes per unit area decreased by 10% over the study period, but grains spike(-1) and 1000-kernel weight increased by 10%. There were no significant increases in harvest index, grain size, or spike fertility, and no significant decrease in quality over time. Future use of Rht genes and rye translocations in breeding programs may increase yield under rainfed conditions. (C) 2017 Crop Science Society of China and Institute of Crop Science, CAAS. Production and hosting by Elsevier B.V. This is an open access article under the CC BY-NC-ND license.Öğe Genetic gains in wheat in Turkey: Winter wheat for irrigated conditions(ELSEVIER SCIENCE BV, 2015) Gummadov, Nurberdy; Keser, Mesut; Akin, Beyhan; Cakmak, Mustafa; Mert, Zafer; Taner, Seyfi; Ozturk, IrfanThe study estimated genetic gain for yield and other traits in winter wheat released for irrigated environments in Turkey from 1963 to 2004. Yield trials including 14 varieties were grown in 16 environments from 2008 to 2012 in provinces of Konya, Eskisehir, Ankara, and Edirne. The highest yields were achieved by recent varieties Kinaci-97 (5.48 t ha(-1)), Cetinel-2000 (5.39 t ha(-1)), Alpu-2001 (5.44 t ha(-1)), Ahmetaga (5.35 t ha(-1)), and Ekiz-2004 (5.42 t ha(-1)) compared to older varieties Yektay-406 (4.17 t ha(-1)) and Bezostaya-1 (4.27 t ha(-1)) released in the 1960s. The progress reached in grain yield in 20 years was 1.16 t ha(-1) or 58 kg ha(-1) (1.37%) per year. This gain was mainly achieved through shorter plant height and increased harvest index. There was no clear tendency of changes in specific yield components demonstrating that new high-yielding varieties may have different ways to reach their yield potentials. The yield gains were accompanied by improved stripe rust and leaf rust resistances primarily based on adult plant resistance genes. The grain quality of the new varieties did not deteriorate over time although most of them were inferior to the bread-making quality check Bezostaya-1, a feature that may require attention in future breeding. (C) 2015 Crop Science Society of China and Institute of Crop Science, CAAS. Production and hosting by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).Öğe Global Incidence of Wheat Rusts and Powdery Mildew During 1969-2010 and Durability of Resistance of Winter Wheat Variety Bezostaya 1(SPRINGER, 2012) Morgounov, Alexey; Tufan, Hale Ann; Sharma, Ram; Akın, Beyhan; Bağcı, Ahmet; Braun, Hans-Joachim; Kaya, Yüksel; Keser, Mesut; Payne, Thomas S.; Sonder, Kai; McIntosh, RobertDisease incidence and severity was studied for winter wheat variety Bezostaya 1 and susceptible checks based on data from international nurseries from 1969 to 2010 and from 51 countries across major winter wheat production regions totalling 1,047 reports. The frequency of leaf rust and stripe rust occurrence was stable over time with marked increases in severity in 2001-2010 especially in Europe and Central and West Asia. Substantial global reductions in stem rust occurrence were recorded and attributed primarily to use of resistance genes although the recent emergence of race Ug99 makes wheat more vulnerable. The occurrence of powdery mildew remained globally stable over time. It was the most important foliar disease in Western and Southern Europe, where the frequency was very high for all time periods coupled with slight increases in severity during 2001-2010. The durable resistance of variety Bezostaya 1 to all four diseases was demonstrated in the study using comparisons of disease severities of Bezostaya 1 and the most susceptible entries. The Lr34/Yr18/Pm38 pleiotrophic set possessed by Bezostaya 1 is currently an important target for selection because it is now amenable to molecular selection. Increased use of genes like Lr34 combined with strategies to minimize cultivation of extremely susceptible varieties will contribute to long term maintenance of low and non-damaging disease levels. The durable disease resistance of Bezostaya 1, combined with its adaptability and good end-use quality, was a significant reason for its huge impact in agriculture over the last 50 years.Öğe Identifying High Yielding Stable Winter Wheat Genotypes for Irrigated Environments in Central and West Asia(Springer, 2010) Sharma, Ram C.; Morgounov, Alexei I.; Braun, Hans J.; Akın, Beyhan; Keser, Mesut; Bedoshvili, David; Bağcı, Ahmet; Martius, Christopher; Ginkel, Maarten vanImproved winter wheat (Triticum aestivum L.) cultivars are needed for the diverse environments in Central and West Asia to improve rural livelihoods. This study was conducted to determine the performance of elite winter wheat breeding lines developed by the International Winter Wheat Improvement Program (IWWIP), to analyze their stability across diverse environments, and to identify superior genotypes that could be valuable for winter wheat improvement or varietal release. One hundred and one advanced winter wheat breeding lines and four check cultivars were tested over a 5-year period (2004-2008). Grain yield and agronomic traits were analyzed. Stability and genotypic superiority for grain yield were determined using genotype and genotype x environment (GGE) biplot analysis. The experimental genotypes showed high levels of grain yield in each year, with mean values ranging from 3.9 to 6.7 t ha(-1). A set of 25 experimental genotypes was identified. These were either equal or superior to the best check based on their high mean yield and stability across environments as assessed by the GGE biplot analysis. The more stable high yielding genotypes were ID800994.W/Falke, Agri/Nac//Attila, ID800994W/Vee//F900K/3/Pony/Opata, AU//YT542/N10B/3/II8260/4/JI/Hys/5/Yunnat Esskiy/6/KS82W409/Spn and F130-L-1-12/MV12. The superior genotypes also had acceptable maturity, plant height and 1,000-kernel weight. Among the superior lines, Agri/Nac//Attila and Shark/F4105W2.1 have already been proposed for release in Kyrgyzstan and Georgia, respectively. The findings provide information on wide adaptation of the internationally important winter wheat genotypes, and demonstrate that the IWWIP program is enriching the germplasm base in the region with superior winter wheat genotypes to the benefit of national and international winter wheat improvement programs.Öğe MEASURING THE IMPACT OF AGRICULTURAL RESEARCH: THE CASE OF NEW WHEAT VARIETIES IN TURKEY(CAMBRIDGE UNIV PRESS, 2015) Mazid, Ahmed; Keser, Mesut; Amegbeto, Koffi N.; Morgounov, Alexey; Bagci, Ahmet; Peker, Kenan; Akin, MustafaThis paper summarizes a study initiated by the Turkish General Directorate of Agricultural Research and ICARDA/CIMMYT Wheat Improvement Program on the adoption of five new winter and spring wheat varieties developed and released by the Turkish national breeding program and through international collaboration in the past 10 years. The study results are based on a survey of 781 households selected randomly in the Adana, Ankara, Diyarbakir, Edirne, and Konya provinces of Turkey. The five new wheat varieties are compared to old improved varieties released prior to 1995 that are also still grown by farmers. Technical and biological indicators of impacts including crop productivity are measured to determine the impact of these varieties. Yield stability is assessed by comparing average yields in normal, good and dry years and by comparing the coefficients of variation of yields by variety. Profitability is measured by the gross margin generated per unit of land. Household income from wheat and for all economic activities are estimated and compared between adopters and non-adopters. Adopters of the new varieties have higher per-capita income than non-adopters as compared to the same group using old varieties. However, the overall impact of the improved varieties is generally low, mainly due to their low adoption levels. Farmers' knowledge and perception of certain variety characteristics and unavailability of adequate and timely seed are the main reasons. Increasing adoption has the potential to improve household income and this requires revising wheat impact pathway to achieve the expected impact.