SOYBEAN CULTIVATION IN CROP ROTATIONS OF THE TRANS-URALS REGION

Abstract

Data on the influence of weather conditions, varieties, predecessors, soil cultivation, and mineral nutrition on soybean yield compared with spring wheat are presented. The research was conducted in short-term (two years) and stationary field experiments (eight years) on leached chernozem soils in the central natural zone of the Kurgan region. In the ecological trial, Siberian (SibNIISK-315, Sibiryachka) and European (Bilyavka) selection soybean varieties were tested in favourable hydrotechnical conditions in 2019, with good soil moisture (predecessor fallow), providing productivity potential at the level of 2.00 – 2.23 t/ ha. With a similar cultivation technology and unfavourable natural factors in 2020, a slight yield advantage was observed for the SibNIISK-315 variety (1.77 t/ha compared to 1.60 t/ha for Sibiryachka and 1.72 t/ha for Bilyavka). The Sibiryachka soybean variety stood out for its grain protein content (35.4%). The yield and grain quality data of these varieties can be considered promising for the conditions of the Trans-Urals region. Cultivating the SibNIISK-315 soybean variety as a second crop after fallow in arid years (ETC 0.3 – 0.6) allowed for successful drought resistance, with soybeans yielding at 1 t/ha. Spring wheat in these years yielded no more than 0.68 t/ha. Under sufficient moisture conditions (ETC 1.0–1.2), soybean yield for ploughing was 1.42–1.78 t/ha, and surface treatment was 1.33–1.66 t/ha. A positive effect on outcome was noted with small doses of nitrogen fertilisers – 10 and 20 kg of active substance per hectare of crop rotation area. With relatively equal yields, surface treatment is a less costly option. Traditional crop rotation (fallow – three years – wheat) and crop rotation with soybeans (fallow – wheat – soybeans – wheat) during the years of research (2015 – 2022) showed similar productivity. Still, higher grain production profitability was achieved in the crop rotation with soybeans: 58.1% compared to 35.8%.