Study of white sugar yield stability of sugar beet (Beta vulgaris L.) cultivars in winter sowing

Water is the most significant limiting factor for sugar beet cultivation in Iran. Autumn sowing of sugar beet in dry climates like Iran consumes less water compared to spring sowing and can be a more suitable option for taking advantage of autumn and winter rains and dealing with the water shortage crisis. It seems that the transfer of sugar beet cultivation from spring to autumn will cause that in addition to consuming much less water in this type of cultivation and increasing the efficiency of water consumption, it will have a significant economic benefit for farmers and will spread quickly. But autumn sowing is facing problems in many areas. Therefore, the current research was conducted to investigate the effect of winter sowing on the quantitative and qualitative characteristics of sugar beet. The experiment was conducted in the form of a randomized complete block design with four replications on 11 early maturity sugar beet cultivars at Jovein, Torbat-Jam, and Moghan agricultural research stations for one, two, and three crop years, respectively. In order to study the effect of genotype-environment interaction and to identify genotypes with general and specific stability, AMMI and MTSI stability analysis methods were used. The combined analysis of variance results based on the AMMI model confirmed the significant effect of the main effects of environment and cultivar at the one percent probability level. The interaction between them also showed a statistically significant difference at the one percent probability level. The analysis of the multiplicative effects of the AMMI model confirmed that the first two components are significant at the one percent probability level and together explain 75.20% of the interaction variation. The bi-plot obtained from the mean white sugar yield and the first principal component of the interaction confirmed the superiority of FDIR19B4028 and Modex cultivars due to their high white sugar yield and stability. According to the bi-plot results obtained from the first two components, there was no appreciable specific adaptability between cultivars with Moghan environment in 2021 and 2020, but on the other hand, a very high specific adaptability was observed between Moghan environment in 2019 with Modex cultivar, Torbat-Jam in 2021 and 2020 respectively with Asia and SVZD2019 cultivars, and Jovein with SVZC2019 cultivar. Cadmus cultivar has general adaptability because it is somewhat close to the origin of the coordinates. Based on the results of the MTSI index, SVZD2019 was ranked first, and FDIR19B4028, Dravus, and FDIR19B3021 were placed in the next ranks of the most ideal sustainable cultivars in terms of all studied traits. In general, four cultivars of SVZD2019, FDIR19B4028, Dravus and FDIR19B3021 are recommended for winter cultivation. The obtained results show that the development of winter sugar beet sowing is certainly one of the important strategies for using seasonal rains and saving water consumption; In this regard, in the winter sowing of sugar beet, choosing the suitable cultivar plays a very vital role, so that it affects most of the quantitative and qualitative characteristics.