Genotypes x Environment Interaction and Stability of Bread Wheat (Triticum Aestivum L.) Cultivar Under Rainfed Conditions

The significant genotype (G) and environment (E) interaction and genetic diversity in the breeding programs are essential issues for the breeder to develop new cultivars. The experiment was conducted in the experimental area of Trakia Agriculture Research Institute Edirne, Turkey at eight environments from 2006-2007 to 2013-2014 growing cycles. In the study, nine released cultivars were used in randomized complete block design with four replications. Grain yield data were subjected to analysis of variance (ANOVA), the additive main effect, and multiplicative interaction (AMMI) and genotype and genotype-by-environment (GGE) biplot analyses. Stable genotypes were identified with GGE biplot and AMMI models. ANOVA and AMMI analysis revealed highly significant (p < 0.01) differences among test environments (E), genotypes (G), and their interaction (G×E). The graphical result from PCI showed that the first principal component PC1 explained 49.43% of the interaction while the second principal component, PC2 explained 29.08% of some of the square interaction. The result of PCA revealed that the 2 principal components (PC1, PC2) contributed 78.51% of the total variability. The environmental effect was responsible for the greatest part of the variation, followed by genotype and genotype by location interaction effects. Genotypes, when tested across eight environmental conditions, showed significant variation in grain yield. The highest grain yield was performed by cultivar Bereket (G8) and followed by Selimiye (G7) and Gelibolu (G4). Environment E4 and E1was found near the ideal test environment of the average environment coordination. It was determined that cultivars G7 (Selimiye) and G8 (Bereket) were well adaptable to all environmental conditions. Cultivar G4 (Gelibolu) was well adaptable to well fertile environmental conditions.