Genetic gains in wheat in Turkey: Winter wheat for irrigated conditions uri icon

abstract

  • The 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/).
  • Wheat 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.

publication date

  • 2017
  • 2015
  • 2015