Aim. To study the impact of an alternative organic-mineral fertilization on the photosynthetic and biological productivity of sugar beet under modernizing it with the latest agrochemical means. Меthods. Short-term field and analytical. Results. The results of research on the impact of an alternative organic-mineral fertilization with different saturation with the latest agrochemicals on the photosynthetic and biological productivity of sugar beets are presented. It was established that the development of the leaf surface, the content of chlorophyll in the leaves, the photosynthetic and biological productivity of sugar beet increased significantly when foliar fertilizing with agrochemicals was carried out against the background of the organic-mineral fertilization. Conclusions. Application of N30 + «Folcrop Combi» + «Folcrop Amin» for foliar fertilization against the background of 5 t/ha of straw + P90K90 under plowing + N90 under pre-sowing cultivation formed the maximum development of the leaf surface: in July – 1920 cm2/plant, in August – 2566, in September – 1790 cm2/plant. The specified fertilization ensured the maximum content of chlorophyll in leaves in July – 2.01%, August – 1.94%, September – 1.80%. The net productivity of photosynthesis in sugar beet plants in August with the application of straw and mineral fertilizers increased compared to the control without fertilizers – in 1.60 times, with additional foliar fertilization – in 1.77-1.93 times. The most intensive processes of photosynthesis occurred with the combined application of 5 t/ha of straw + P90K90 under plowing + N90 under pre-sowing cultivation + «Folcrop Combi» + «Folcrop Amin» − the net productivity of photosynthesis was 11.08 g/m2 per day. The use of a modernized organic-mineral fertilization (5 t/ha of straw + P90K90 under plowing + N90 undern pre-sowing cultivation + N30 + «Folcrop Combi» + «Folcrop Amin») ensured the highest biological productivity of sugar beet: yield of roots – 60.3 t/ha, sugar harvest – 10.37 with exceeding the control without fertilizers – by 19.1 and 3.20 t/ha.

Purpose. Investigate the effect of doses and methods of applying nitrogen fertilizers on the productivity of sugar beets after plowing in for fertilizer of winter wheat straw. Methods. Short-term field and analytical. Results. The results of research on the effect of doses of nitrogen fertilizers applied in spring under pre-sowing cultivation over the background of straw and mineral fertilizers applied under plowing on the productivity of sugar beet are given. The yield of sugar beet, sugar content in roots and biological productivity of crop under the use of alternative organic-mineral fertilizations were determined. Conclusions. It was established that alternative organic-mineral fertilizations significantly increased the biological productivity of sugar beet. Application of mineral fertilizers in autumn under deep plowing in a dose of N90Р90К90 against a background of 5 t/ha of straw was determined to be less biologically productive: the yield of roots – 49.9 t/ha, sugar harvest – 8.73 t/ha, exceeding the control without fertilizers by 8.7 and 1.56 t/ha, respectively. The application of N90 in pre-sowing cultivation against the background of 5 t/ha of straw + P90K90 under plowing was determined to be the most optimal for sugar beet: root yield – 55.8 t/ha, sugar harvest – 9.71 t/ha, exceeding the control without fertilizers by 14.6 and 2.54 t/ha, respectively. Increasing the nitrogen dose in the spring by more than 90 kg/ha was not accompanied by a significant increase in yield, reduced the sugar content in roots, and therefore was ineffective.

It has been established that sugar beet, when grown in conditions of unstable moisture on podzoliс chernozem, form a high energy productivity of biomass under the use of alternative organic-mineral fertilization systems and require the application of increased doses of nitrogen and potassium fertilizers to form their balanced balance in the soil. The maximum energy productivity of the ‘Bulava’ hybrid was achieved with the application of nitrogen fertilizers in the spring in the pre-sowing cultivation at a dose of 90 kg/ha on the background of 5 t/ha of straw + Filazonite, 10 l/ha + P90K90 under deep ploughing in autumn: bioethanol energy output — 118 GJ/ha, biogas — 54 GJ/ha, total energy output — 172 GJ/ha, exceeding control without fertilizers — by 37, 16 and 53 GJ/ha, respectively.