ECONOMIC EFFICIENCY OF DEBUT SOYBEAN VARIETY CULTIVATION WITH AND WITHOUT SOIL TILLAGE (DIRECT SEEDING) AT DIFFERENT SEEDING RATES IN THE AMUR REGION

The objective of the study is to compare the efficiency of soybean sowing options (direct and with soil tillage) at different seeding rates. The studies were conducted under the conditions of a production field trial laid out at the Serdyukov A.N. peasant farm in the forest-steppe zone of the Amur Region in 2022–2024. The object of the study was the Debut soybean variety, developed in the Far Eastern State Agrarian University and included in the State Register of the Russian Federation in 2022. The experiment design included 2 factors: 1 – sowing on tilled soil (double spring disking to a depth of 16–18 and 6–8 cm without autumn tillage) and direct sowing (without soil tillage); 2 – seeding rate: 400,000, 500,000, 600,000 and 700,000 viable grains/ha. The predecessor crop was grain corn. The trial was replicated four times, with a plot area of 900 m2. The soil in the experimental plot was meadow chernozem with a humus content of 4.15 %. Direct seeding of soybeans was found to yield higher revenue (94,306 rubles/ha), significantly reducing soybean production costs, and significantly increasing profits. A comparison with tilled soil seeding highlights its advantages: revenue is higher by 3,148 rubles/ha with a cost reduction of 5,587 rubles/ha. Direct seeding of soybeans reduces production costs to 14,442 rubles per tonne and is more cost-effective, especially when using reduced seeding rates (400,000 and 500,000 viable seeds/ha). The additional seed costs when increasing seeding rates to 600,000 and 700,000 viable seeds/ha are not offset by the yield gains.