Evaluation of White Sugar Yield Stability of Some Commercially Released Sugar Beet Cultivars in Iran from 2011-2020

High yield and yield stability across a range of environmental conditions is one of the main objectives of crop breeding programs. In this study, white sugar yield stability of nine sugar beet cultivars commercially released in Iran from 2011 to 2020 with an introduced foreign cultivar as check was evaluated using randomized complete block design with four replications in six research field stations; Karaj, Ardabil, Kermanshah, Mashhad, Moghan, Miandoab, in four cropping seasons 2017-2021. The combined analysis of variance revealed that effects of genotype, year, location, and year × location, genotype × year, genotype × location and genotype × year × location were significant (p ≤ 0.01) on white sugar yield. Analysis of genotype × environment interaction showed that the first seven components were significant (p ≤ 0.01). Based on AMMI1 analysis, cv. Asia, cv. Shokoufa and cv. Arta had white sugar yield stability. Linear mixed model analysis showed that the effects of genotype and genotype × environment interaction were significant (p ≤ 0.01) on white sugare yield. Based on the BLUP method, cv. Perfecta, cv. Asia and cv. Shokoufa had the highest predicted mean value of white sugar yield. Biplot of white sugar yield with the WAASB index showed that cv. Asia, cv. Arta and cv. Shokoufa had higher sugar yield as well as higher white sugar yield stability. Ranking of sugar beet cultivars based on WAASB/white sugar yield ratio identified cv. Arta, cv. Asia and cv. Shokoufa as high yielding with white sugar yield stability. Simultaneous ranking and selection of cultivars based on 50:50 WAASB/white sugar yield ratio resulted the same. Therefore, cv. Asia followed by cv. Shokoufa and cv. Arta had relatively higher WAASBY indices. Considering the results of this study, cv. Asia, cv. Shokoufa and cv. Arta were identified as high yielding with higher white sugar yield stability.