Interpretation of Genotype by Environment Interaction for Barley Genotypes Via Simultaneous Selection for Yield and Stability
Shadi Faramoushi, Hamid Hatami Maleki, Behrouz Vaezi, and Naser Sabagnia
Genotype × environment (GE) interaction was investigated for grain yield of barley (Hordeum vulgare L.). Data included were 18 genotypes and 15 environments (five locations and three years). Interaction effect was modeled by four types of stability parameters and studied parameters were plotted against mean yield performance for graphic analysis of stability and simultaneous selection for yield and stability. About 60% of the total variance was explained by environment differences, about 24% by GE differences and 15% by genotype differences. G8, G10 and G18 according to Si2 and G2, G6 and G10 considering CVi were stable while G2, G6 and G10 were identified as the most stable genotypes based on θi, θ(i), Wi2 and σi2 parameters. Genotypes with bi and βi (coefficients of linear regression) values greater than 1 (such as G3, G7, G15 and G17) indicated higher yield in more favorable environments. Overall based on Type IV stability, G8, G10, G11 and G18 were identified as the most stable genotypes for each of the five locations. According to graphic analysis of Si2 and CVi parameters, G2, G5, G6, G10 and G12 were the most stable genotypes while based on θi, θ(i), Wi2 and σi2 parameters, G1, G2, G4, G5, G6, G10, G12 and G15 were identified as the most favorable genotypes. Based on graphic analysis, G1, G4, G6, G10 and G15 were common with the high-yielding genotypes. Finally, G1 (2 325.2 kg ha-1) and G15 (2348.6 kg ha-1) were the most favorable genotypes for barley grain yield and are therefore recommended for commercial release.