FORMATION OF SUGAR BEET ROOT YIELD AND SUGAR CONTENT IN RELATION TO GENETIC TYPE OF VARIETY AND AGROECOLOGICAL CONDITIONS OF YEAR

Field trials carried out in 2016-2018 at the PD Devio Nove Sady plots studied the influence of the climatic conditions of the year on the root yield and sugar content of 11 varieties of sugar beet (Leopold, Francessa, Vandana, Alabaster, Kosmas, Marenka, Sioux, Varios, Antek, Brian, Plinius). The production-experimental area is located at the border of maize and beet production areas. Analysis of the experimental data found a highly significant effect of the year, variety, and also the interaction of climatic factors and variety on the root yield and sugar content. The genetic potential of the varieties was strongly influenced by environmental factors. In 2017, the highest average sugar content of the tested varieties was 18.29%; it was also the year that saw the biggest differences in sugar content among the varieties with a range of 1.78%, and the lowest variability of the root yield with a range of 9.78 t ha(-1). In 2016, the average root yield of the tested varieties was 91.44 t ha(-1) and in 2018 it was 70.59 t ha(-1). The range of the highest and lowest root yields among varieties was equal to 22.3 t ha(-1) in 2016 and 22.5 t ha(-1) in 2018. The minimum average sugar content (15.45%) of 2016 was accompanied by the lowest variability in the sugar content of the tested varieties. The results showed that in 2017, when the highest average sugar content was recorded, there were also the biggest differences in sugar content between varieties together with high stability in root yields and on the contrary, in the years more suitable for production of the roots, greater differences between root yields of the tested varieties were observed with lower differences in sugar content.