Annotation

The research presents results of the studies on the influence of basic tillage methods and fertilizer levels on photosynthetic productivity, yield and sugar content of sugar beet. Field experiments were hold under conditions of the Western Forest-Steppe of Ukraine on dark gray podzolic light loamy soils.

It is determined that indicators of photosynthetic activity of sugar beet plants maximum depend on fertilization levels. Comparing to the control variant with no mineral fertilization, application of fertilizers in the norms of N₁₈₀P₁₃₅K₂₁₀, N₂₄₀P₁₈₀K₂₈₀andN₃₀₀P₂₂₅K₃₅₀ has improved photosynthetic potential by 59 %, 103 % and 236 % respectively, regardless of the way of principal soil treatment. Net productivity of photosynthesis got its maximum value under application of fertilizers in the norms N₁₈₀P₁₃₅K₂₁₀ – in case of shallow plowless soil treatment – 5,64 g of dry matter per m² of a leaf surface daily, and under deep under-winter plowing at the depth of 28–30 cm – 5.62 g of dry matter per m² of a leaf surface daily. The further increase of fertilization level up to N₂₄₀P₁₈₀K₂₈₀andN₃₀₀P₂₂₅K₃₅₀ has caused some fall of the indicator of net productivity of photosynthesis, relating to such norms of fertilizers as N₁₈₀P₁₃₅K₂₁₀, that can be explained by a considerable increase of the area of a leaf surface of plants at higher backgrounds.

The optimization of the system of sugar beets fertilization allows ensuring the growth of the yield capacity of root crops. It is determined that the highest yield capacity of sugar beets is formed under fertilization in the norm N₃₀₀P₂₂₅K₃₅₀, particularly 89.2 and 90.7 t/ha, depending on the way of principal soil treatment, that is three times more as compared to the control (26.5 and 25.9 t/ha). Fertilizer levels affected the sugar content of the roots in both main tillage methods equally. The highest rates of 17.4–17.5 % were obtained on the control variants without fertilizer. Sugar harvesting depended on yield. The highest rates were obtained according to N₃₀₀P₂₂₅K₃₅₀ – 14.79–14..95 t/ha, depending on the method of basic tillage.