Spring barley productivity depending on agronomic factors in the Left-Bank ForestSteppe

Purpose. To determine the effect of fertilizers on spring barley productivity depending on the forecrop and soil tillage in the Left-Bank Forest-Steppe of Ukraine. Methods. Field research was conducted during 2022-2024 at the Cherkasy Experimental Station as part of two stationary experiments to study the effect of forecrops, tillage methods and fertilizer doses. Field, laboratory and statistical analysis methods were used. Results. Spring barley in wheat – soybean – barley and soybean – wheat – barley crop rotations provides a yield of 4.7-4.9 t/ha, profit – of 11.8-13.0 thousand UAH/ha, profitability – of 72-79%, a grain self-cost – of 3.3-3.5 thousand UAH/t, and a feed unit – of 2.2-2.3 thousand UAH/t. Plowing with application of a N30P20K30 dose of fertilizer increases the grain and feed units yield by 72-73%, protein yield – by 9% compared to the control (grain yield – 2.01 t/ha, feed units – 3.17 t/ha, protein yield – 0.23 t/ha). N60P40K60 compared to N30P20K30 increases the forage grain yield by 33%, feed units – by 59%, protein by – 33%, profit – by 50% and reduces the cost. The highest profit (13 thousand UAH/ha) and profitability (79%) are in a three-crop rotation with soybeans, the grain self-cost is 3.3 thousand UAH/t. Conclusions. After the best forecrops, spring barley provides a 4.1-4.6 t/ha yield, a 11.8-13.0 thousand UAH/ha profit, a profitability of 77-79% rate of return, and a 3489 UAH/t self-cost. The optimal doses of fertilizers for barley after corn are N30P20K30 and N60P40K60, which provide a 4.35-4.61 t/ha forage grain yield, 5.45-8.6 t/ha feed units, 0.30-0.40 t/ha of digestible protein, a 8.1-13.1 thousand UAH/ha profit, a 3.557-4.478 thousand UAH/t grain self-cost, 2.462- 2.657 thousand UAH/t of feed unit.