Aim of the investigations was to reveal changers in soil fertility and yield of main crops in a grain-arable crop rotation with fertilizer effect in 1st rotation (short -term application) and 10th rotation (long-term application) under conditions of the Central Black-Earth Region. The work was performed in a long-term field experiment using low-humic leached chernozem under conditions of Voronezh region. The data of 1936–1945 (1st crop rotation) and 2018–2022 (10th rotation) years were analyzed. The experiment scheme including saturation of 1 ha of arable land with fertilizers: without fertilizers, N10P10K10 + 2.8 t/ha of manure, N20P20K20 + 2.8 t/ha of manure, N30P30K30 + 2.8 т t/ha of manure, and N10P10K10 + 5.6 t/ha of manure. Change of soil fertility in the layer of 0–20 cm from 1 to 10 rotation under influence of fertilizers appeared as increase of hydrolytic acidity (by 5.26… 83.3 %), exchange K2O content (by 18.9…74.4 %), cation exchange capacity (by 27.8…35.7 %) and mobile P2O5 (by 7.81…9.00 %) (when using N20P20K20 + 2,8 t/ha of manure and N30P30K30 + 2,8 t/ha of manure); also, decrease of humus content by 0.41…0.73 %, N-NO3 by 25.3…47.7 % and P2O5 by 13.3–31.6 % in the control and in the variants with N10P10K10 + 2.8 or 5.6 t/ha of manure was noted. Long-term application of fertilizers in a crop rotation improved grain yield of barley by 11.3…50.1 %, oats by 4.0…51.2 %, winter wheat by13.4…30.6 % and sugar beet roots by 15.0…36.7 %, and reduced green mass of a clover 6.1…23.0 %. But, in addition, it increased by-products’ yield of each crop by 6.1…23.0 %. Productivity of the fertilized arable land per 1 ha increased by 3.30…18.3 % from 1st to 10th rotation (minus yield improvement by 0.96 thousand grain units/ha due to cultivation of more productive modern varieties). Long-term application of N30P30K30 + 2.8 т t/ha of manure ensured the greatest level of crop rotation soil fertility and productivity. This was achieved by twice-repeated application of N135P135K135 for sugar beet and one application of 25 t/ha of manure in fallow during 9-field crop rotation.
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