TRACING HIGHLY ADAPTED STABLE YIELDING BREAD WHEAT (TRITICUM AESTIVUM L.) GENOTYPES FOR GREATLY VARIABLE SOUTH-EASTERN TURKEY

Abstract

Wheat (Triticum aestivum L.) is the most widely adapted and cultivated cereal grain in the world. In 2013 cropping season, wheat was harvested on 1.3, 7.8, and 214 million ha in south-eastern Turkey, Turkey and World, respectively. Breeding programs in the Turkey have achieved tremendous gains in grain yield over past two decades. However, yield fluctuated over the years due to change in environmental conditions and genotype by environment interactions. Therefore, this study was conducted with overall objectives to identify high yielding and stable candidate genotypes for release in southeastern Turkey. A total of 25 genotypes with 20 advanced experimental lines and five check cultivars were planted at 10 locations in south-eastern Turkey in 2010-11 cropping season. Grain yield stability was determined using Eberhart and Russel, AMMI and GGE-biplot methods. Based on these results G1, G12, G13 and G19 were identified as the potential candidate genotypes for release. GGE-biplot classified south-eastern Turkey into two mega-environments. AMMI and GGE biplot explained 86.49% and 86.43% of the total variation for grain yield, respectively. These result suggested that all three methods were equally efficient in determining the stability of the genotype. However, the GGE biplot methodology is more preferred than AMMI and Eberhart and Russel because it facilitates clearly visualize which-won-where pattern and the discriminating ability of environments.