Stability Analysis of Genotype × Environment Interaction Effect on Sugar Yield in Sugar Beet Hybrids

Testing plant varieties under different regions is necessary to assess their stability. In this study, 17 sugar beet genotypes were evaluated in a randomized complete block design with six replications in five regions including Karaj, Hamedan, Miandoab, Mashhad, and Shiraz. After checking the homogeneity of mean squares in five experiments by Bartlett’s test, analysis of the combined was performed for sugar yield. In this analysis, location, genotype and genotype × location interaction effects were significant. Based on regression coefficient and deviation from regression parameters, genotypes G2, G6, G9 and G13 were the most stable genotypes. Genotypes G2, G3, G5 and G6 had the highest stability based on Shukla’s stability variance and Wrick’s ecovalence. Based on superiority measure, genotypes G6 and G9 and based on coefficient of variation genotypes G2 and G5 were identified as the most stable genotypes. Using coefficient of determination, genotypes G3, G5 and G6 were selected and by Tai’s regression method, genotypes G2, G6 and G12 genotypes were selected as the most stable genotypes having sugar yield higher than average. Based on the above mentioned methods, genotype G2 was recognized as the most suitable genotype for sugar yield stability.