This article studied the influence of sowing dates of various biological forms of sugar beet on the productivity of root crops in specific soil and climatic conditions. The role of sowing dates on seed germination, the dynamics of the formation and drying of sugar beet leaves, the number of functioning leaves during the growing season, as well as the dynamics of the growth of the leaf surface area of sugar beets depending on varietal characteristics and sowing dates are shown. Both the lack and the excess of any factor negatively affect the productivity of plants. Therefore, when developing agricultural techniques for crop cultivation, it is important to take into account the timing of sowing, the specifics of the action of mineral fertilizers, the genetic properties of hybrids, climatic and weather conditions, soils, states of organogenesis, phases and interphase periods of plant growth and development. Operational management of the process of crop formation, taking into account varietal characteristics, during the growing season by selecting the appropriate agrotechnical measures and the terms of their implementation should be carried out taking into account the state of crops and meteorological conditions. The scientific basis for agrotechnical measures is the theory of the dynamics of crop formation. It was established that during the early sowing period, the reserves of productive moisture and nutrient reserves in the soil in the first half of the growing season are greater than in the later ones, which ensures the rapid development of the root system, the growth of the leaf surface, the increase in the mass of root crops and the accumulation of sugar in them. The highest yield of root crops and sugar yield per hectare was obtained when sowing triploid hybrid Okhtyrskyi and diploid hybrid ICB 0902 during the first sowing periods. Sowing beets five days later reduced yield by 3.8 t/ha and sugar content by 0.1 %. Late sowing dates sharply reduced the yield and sugar content of root crops. Key words: sugar beet, germination, yield, oneseeded, sugar content, sugar collection.

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Modern sugar beet hybrids have a potential root crop capacity of above 50.0 t/ha and sugar content of 16.1–18.5 %. Seeds with a germination rate of not less than 90 % are being used in this case, highly efficient energy-saving technologies based on the use of agricultural techniques (crop rotation, fertilization system, soil tillage system, sowing at the final density), protection against pests and diseases, the method of harvesting root crops are used. The performance of the sugar beet hybrid is mainly determined by the genetic information contained in the seeds and the conditions in which the plants grow. The purpose of the research was to investigate the varietal features of growth, development and productivity of sugar beet in the conditions of the central part of the Right-bank forest-steppe of Ukraine. The following sugar beet hybrids were used for sowing: Olzhych, Etude, Zluka, Constanta and Anichka with the fraction of 3.5–4.5 mm and laboratory germination of 85–90 %. The growth and development of sugar beet plants of different hybrids differed. There was a tendency for more positive germination of seeds and a more complete density of seedlings in the hybrid Constanta. The productivity of the sugar beet root crops is determined by the yield, sugar content and sugar harvest. Crop capacity of the male sterile hybrids studied averaged from 46.4 to 55.6 t/ha over the three years of studies, sugar content – 15.6–17.0 % and sugar yield – 7.4–9.5 t/ha. Hybrids Zluka and Constanta appeared to be the most adapted to the conditions of the central part of the right-bank forest-steppe of Ukraine. Thus, over three years, the Zluka hybrid had an average crop capacity of 55.6 t/ha, the sugar content of the roots was 16.1 %, the sugar harvest was 9.0 t/ha, and the hybrid Constant had a yield of 55.1 t/ha, the sugar content of the roots – 16.2 %, sugar yield – 8.1 t/ha. Key words: sugar beets, hybrids, field germination of seeds, sugar content, sugar yield.