The study was conducted to determine the effects of genotype (G), environment (E), their interaction (GEI) and genetic gain on yield and grain quality traits in Turkish spring wheat cultivars released between 1964 and 2010. We conducted a multi-environment trial at three testing locations: Adana, Adapazarı, and Izmir, during the 2009, 2011 and 2013 cropping seasons and tested 35 cultivars released by the respective breeding programs. Allelic variations of high and low molecular weight glutenin subunits (HMW-GS and LMW-GS) and 1B/1R translocation was also determined and evaluated in all cultivars. Comparing yield across three locations, Adana (6416 kg ha -1 ) yield was relatively higher than in Izmir (5887 kg ha -1 ) and Adapazarı (5205 kg ha -1 ) (P<0.001). Overall, GY was influenced by the varieties, testing location and breeding programs (P<0.001). Cultivars from Izmir breeding program performed relatively better (6174 kg ha -1 ) than those from Adana (5996 kg ha -1 ) and Adapazarı (5351 kg ha -1 ) (<0.001). We recommend Ziyabey-98, Menemen, and Basribey-95, for stable grain yield in spring wheat production across the studied regions because of their wide adaptability, and Pamukova-97 for future breeding to improve grain quality parameters. We found three breeding programs have successfully increased the grain yield and quality traits for 46 years. As a group, cultivars released after 2000 had the highest yield indicating breeding progress. Genetic gain for GY was 30.9 kg ha −1 per year from 1964 with annual increase compared to the yield of older cultivar Akova B-2 (4102 kg ha -1 ) which constitutes a 0.75% rate of genetic gain. Improvement in grain quality was related to change in protein composition rather than an increase in protein content whereas yield improvement seems to mainly be related to increases in test weight and 1000 kernel weight. High molecular weight glutenin subunit (HMW-GS) 5+10 showed an increase in frequency whereas 2+12 showed a decrease over the breeding period.

Genetic gain for grain yield was evaluated in 35 Turkish spring wheat varieties released between 1964 and 2010. The germplasm comprised varieties developed by the East Mediterranean Agricultural Research Institute (ARI) in Adana, the Maize Research Station in Adapazarı, and Aegean ARI in İzmir. Out of 34 varieties studied, 24 were selected from CIMMYT germplasm. The trials were conducted during 2009-2013 at the same three sites. Average yearly genetic gain for all varieties was 30.9 kg/ha or 0.62%. The top five highest yielding varieties were all released after 1998: Ziyabey, Menemen, and Meta (İzmir), and Karatopak and Ceyhan (Adana). Plant height had a clear tendency to decrease over time. Genetic gain in yield was associated with genetic gains in harvest index (0.51%), the number of spikes/m2 (0.29%), and the number of grains/spike (0.26%). Kernel size and biomass did not change over time and represent traits to be explored in the future. The newest varieties combined higher yield with yield stability. Resistance to leaf rust contributed greatly to yield genetic gain. Turkish breeders made a substantial impact on national grain supply and food security. Future breeding strategies shall combine the utilization of CIMMYT germplasm, a diverse modern gene pool, and genetic resources in an integrated national breeding program.

Abstract

Öz: Bu araştırma, bazı ekmeklik buğday çeşit ve hatları ile yerel çeşitlerin kalite parametrelerinin belirlenmesi amacıyla yürütülmüştür. Çalışmada 17 ileri kademe ekmeklik buğday hattı, 8 adet yazlık karakterli tescilli çeşit ve 5 adet yerel çeşit materyal olarak kullanılmıştır. Çalışmada yer alan genotiplere ait Protein Oranı (%), Zeleny SDS (ml) ve Farinograf değerleri incelenmiştir. Yapılan çalışma ile genotiplerin ayrıntılı kalite potansiyelleri ortaya konularak karşılaştırılması amaçlanmıştır. Elde edilen sonuçlar özetlendiğinde, protein oranları %9.1-14.6, Zeleny sedimantasyon değerleri 14-50 ml, arasında değişim göstermiştir. Ayrıca genotiplerin farinograf analizi ile hamur yoğurma özellikleri belirlenmiştir. Farinograf cihazı ile yapılan ölçümlerin bir sonucu olan Farinograf Kalite Numarası (FQN) 22 mm ile > 200 mm arasında değer göstermiştir.