Productivity formation and processability of sugar beet in the conditions of continental climate

Purpose. To reveal the peculiarities of yield formation and processability of sugar beet roots in the conditions of the Steppe of Ukraine through optimizing the cultivation technology. 
Methods. The field experiment was conducted in the years 2020–2021 in the conditions of Chkalov Agrocompany LLC (Kirovohrad region). A drought-resistant diploid sugar beet hybrid ‘Magister’ (SESVanderHave) was grown against the background of the application of a moisture retainer (without hydrogel and hydrogel Aquasorb, 300 kg/ha) and different fertilization systems [without fertilizers – control; manure, 20 t/ha; N170P180K350; Leonardyt, 400 kg/ha; Parostok-20, 400 kg/ha]. Organic and mineral fertilizers (PK) were applied in autumn under plowing, while nitrogen component was applied under early spring cultivation. The adsorbent was applied to the soil two weeks before sowing the crop locally in the zone of the row to be, based on the data of the GPS tracker. The rest of the agricultural activities carried out were generally accepted components of cultivation technology in the research area. 
Results. As a result of rather difficult weather conditions in 2020, the yield of root crops was only 30.3 t/ha on average in the experiment. The lowest level yield (26.0 t/ha) was obtained in the plots of both controls without fertilizer, while the application of 20 t/ha of manure yielded 29.0–30.0 t/ha. The mineral system (N170P180K350), despite its significantly lower efficiency in the treatment without Aquasorb hydrogel (31.0 t/ha), when it was applied to the soil before sowing the crop, ensured the maximum productivity of sugar beets – 34.0 t/ha. In addition, against the background of the hydrogel, the effectiveness of Leonardyt and Parostok-20 increased significantly – yield increases by 7.0 and 6.0 t/ha, respectively. The maximum content of sugars in roots was noted under the mineral fertilization system against the background of Aquasorb hydrogel – 16.3 against 15.0% in the control. However, in the same treatment, the highest content of α-amine nitrogen was also obtained, which significantly reduces the yield of sugar at the factory. In 2021, due to favorable weather conditions during the crop vegetation, the yield of root crops was 55.6 t/ha on average in the experiment, which is almost twice as high as the previous year. As predicted, the lowest yield was obtained in the treatments without fertilizers – 49.7–50.2 t/ha, with manure application – 50.7–53.3 t/ha. Significantly higher, however, unlike in 2020, the indicators for the mineral fertilizer system were 56.9–58.1 t/ha. The most effective from the point of view of the formation of sugar beet productivity were Leonardyt and Parostok-20 yielding 58.1–58.6 and 59.2–61.6 t/ha, respectively. The maximum sugar content of roots was ensured by the use of Parostok-20 fertilizer, both on the background of Aquasorb hydrogel and without it (17.8% compared to control 15.8%). 
Conclusions. Weather conditions during the vegetation of sugar beets are the most significant factor that determines the level of their productivity, as well as the effectiveness of applied agricultural measures. In all treatments with fertilizers, a significant increase in crop yield was observed, and the amount of the obtained increments largely depended on both their type and the use of hydrogel, especially under unfavorable growing conditions. On average, during the research period, the highest indicators of sugar yield were obtained in the treatment with the use of organic fertilizers of the new formulation Leonardyt and Parostok-20 on the background of Aquasorb hydrogel, which indicates the feasibility of their further implementation in the cultivation technology for sugar beet.