Assessment of Root and White Sugar Yield Stability of Sugar Beet Genotypes

To assess root and white sugar yield stability of 11 spring sugar beet genotypes together with three check cultivars, a field experiment was carried out using randomized complete block design with four replications in six agricultural research stations; Toroq (Mashhad), Zarghan, Khoy, Kermanshah Miandoab, and Karaj, Iran, in 2020 and 2021. Combined analysis of variance showed that genotype × environment interaction was significant (P < 0.01), and genotypes had different performance in different environmental conditions. Based on regression coefficient, deviation from regression, Shukla’s stability variance, Wrick's ecovalence, and coefficient of determination, GB-6 and GB-10 genotypes were identified with high root and white sugar yield and yield stability. Although the number of genotypes with yield stability increased by using superiority measure and coefficient of variation, three genotypes including; GB-11, GB-10, and GB-2 showed the highest yield stability for root and white sugar yield, respectively. Using GGE biplot method, GB-11, GB-10, GB-2 and GB-6 were identified with higher root and white sugar yield, than average of all genotypes, and higher yield stability, respectively. Considering the results of this research, GB-6, GB-11, GB-2, and GB-10 were identified as high-yielding genotypes with high yield stability.