In this study, we investigated the influence of soil cultivation method on the productivity and quality of pasture grass fodder. We found that increasing the depth of cultivation from 8–10 cm to 20–22 cm (using surface tillage with disk implements) improved the productivity of all the grass species studied – <em>Phleum pratense</em>, <em>Lolium perenne</em>, <em>Festuca </em><em>orientalis</em>, <em>Dactylis glomerata</em>, <em>Bromus </em><em>inermis</em>, <em>Phalaris arundinacea</em>, <em>Festuca</em><em> </em><em>rubra </em>– by an average of 2%–3% at an LSD₀₅ of 0.30 t ha⁻¹, over a period of 3 years. On average, the most important factor influencing the production of 1 ha of dry mass appeared to be the species of grass, accounting for 57% of the variation. The depth of soil tillage was also important, accounting for 43% of the variation. Of all the species studied, the highest productivity was exhibited by <em>Lolium perenne </em>(0.35 t ha⁻¹ of dry weight). Increasing the soil cultivation depth led to an increase in the content of crude protein and albumen (0.9%–1.1%). According to the analysis of organic matter content and digestibility of the fodder, across the different depths of soil cultivation, the early ripening species <em>Dactylis glomerata</em>, and the average ripening species <em>Festuca </em><em>orientalis</em>, <em>Lolium perenne</em>, and <em>Bromus </em><em>inermis</em>, performed best. Considering the different depths of soil cultivation, <em>Lolium perenne </em>[154 g; surface tillage (disking) 8–10 cm] and <em>Festuca</em><em> </em><em>orientalis </em>(152 g; ploughing 20–22 cm) provided the most fodder units with digestible protein.

The problem of post-harvest winter rapeseed crops usage influencing siderate and green fodder, oil radish impacting siderate and forage, root and post-harvest remains of winter wheat, and also cattle manure (40 t/ha) influencing the weed littering of maize and grain under conditions of grain-cultivated crop rotation has been revealed by PS of NUBiP of Ukraine - Agronomic research station. It has been proved that the cleanest crops of maize on the typical low-humus and light-loamy black soils remained in the variants where its predecessors were oil radish and winter rape on green fertilizer. Compared to control (root and post-harvest remains of winter wheat), weed amount decreased by 54 and 37% accordingly. Oil radish had a sufficient toxic effect on weeds as it was evidenced by their weight which in this variant decreased under shelf cultivation by 72% and under chisel cultivation - by 61%. Higher yield of maize for both chisel and shelf cultivation was forming in variants with oil radish for siderate and green fodder. The yield increase was 0.3-1.0 under shelf cultivation and 0.7-1.2 t/ha under chisel cultivation.

Analysis of changes in hydrothermal conditions of growing crops in the forest steppe zone of Ukraine over a period of 2004–2016 showed that by the average monthly air temperature more than a half of the years under study and by rainfall nearly a third of the researched period differed significantly from the average long-term value and were close to extreme weather. Statistical analysis of long-term indicators of the air temperature regime is evidence of a steady trend towards an increase in average annual air temperature with significant fluctuations in indices in separate periods from 7.9 ± 2.9 to 10.0 ± 2.5oС and a decrease in the amount and instability of natural moisture entry. The influence of weather conditions on the formation of productivity of spiked cereals (winter and spring wheat, spring barley) and maize was assessed at the current agrometeorological risks in the forest steppe of Ukraine. Based on the correlation-regression analysis, mathematical models were created that reproduce the dependence of grain yields upon the complex weather conditions of the growing season, the impact of which reached 60–70%. The conditions of eight years (2006–2008, 2011–2014 and 2016), when the hydrothermal index for the vegetation period was 1.13–1.76, turned out to be optimal by hydrothermal indicators to harvest maize yield at 5.83–9.47 t/ha. However, the years of 2005, 2009–2010 and 2015 were unfavorable as they received precipitation by 120 mm lower than a norm or 36% of the norm. The rainfall by 37–61% lower than a norm in June–July and grain yield 3.12–6.51 t/ha were also characteristic of the years mentioned above.

The research shows, that an increase of phytocoenoses provided an increase of phytomass volume in the biological cycle from 63.5 to 114.3 t/ha. The yield of phytomass in a crop rotation, different in structure and set of crops, was as follows: for four-field and five-field crop rotation - 63.5-86.7 t/ha, six field - 89.4, seven-field - 96.9, and eight-field - 114.3 t/ha. The optimization of the ratio of grain, technical and fodder crops allowed us to regulate quantitative parameters of crops’ phytomass, which was alienated from agrocoenosis. The yield of the main products, alienated from the field was, as follows: in four-field crop rotation -20.7 t/ha, five-field - 26.6, six-field -37.8, seven field -28.4 and eight field - 41.3 t/ha, which was 32.6%, 30.7%, 42.3%, 29.3% and 36.1%,respectively. The rest returned to the soil with by-products and crop remains. The total amount of nutrients (NPK) in the phytomass, involved in the circulation, was within the range for four-field crop rotation (100% of grain crops) – 1.814 kg/ha, five-field (80% grain and 20% technical) – 2.368 kg/hectare, six-field (66.8% of cereals, 33.2% of technical ones) - 2,599 kg/ha, seven-field (57.2% of cereals and 42.8% of technical) - 2.956 kg/ha, eight-field (62.5% of cereals, 25.0 % of technical, 12.5% of fodder) –3.491 kg/ha.

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