The purpose of the research, carried out in 2012-2020, was to determine the impact of maturity of different groups of cultivars and weather conditions during the growing season on the vitamin C and nitrate content in potato tubers, as well as to study the relationship between these components. The research was carried out in light soil, on 39 edible cultivars divided into 3 maturity groups: very early (6), early (12) and medium-early (21). Each cultivar was grown in a 3-year cycle. Straw and white mustard catch crop were used as organic fertilizers. Mineral fertilization was applied, with a dose of 100 kg N ha-1, 26.2 kg P ha-1, 99.6 kg K ha-1. The content of vitamin C was determined using the Tillman’s method. Nitrates were determined according to the colorimetric method based on the Griess test. The assessment of weather conditions during the research period was done according to the Selyaninov´s hydrothermal coefficient. Significant differences were observed in the vitamin C and nitrate content in tubers, and the relationship between these components and the maturity groups of cultivars as well as weather conditions during the research period. The highest levels of vitamin C and nitrates were found in tubers from the very early maturity group, and the lowest - from the medium-early maturity group. The weather conditions during the research period had a greater influence on the vitamin C and nitrate content in tubers than the maturity group of cultivars. During wet years, the ratio of vitamin C to nitrates was significantly higher. A more favourable ratio of vitamin C to nitrates was observed in cultivars from the early and mid-early maturity groups than from the very early group.

26.4.2021