Influence of Agrotechnical Practices and Sowing Time in Various Weather on Soybean Yield

Abstract For seed germination and the formation of a good soybean crop, significant reserves of soil moisture are required, which depends on the autumn-winter soil preparation, weather conditions and planting dates. The purpose of this study is to identify the impact of the main tillage technology on its agrophysical properties and conditions for the growth and development of soybean plants. Experimental crop rotation: soybean – winter wheat was carried out under favourable (hydrothermal coefficient 1.46) and dry (hydrothermal coefficient 0.66–0.87) weather conditions. The main tillage was carried out with a stratifier PRSM-5 to a depth of 15–17 cm or a chisel plough PCh-2.5 to a depth of 25–27 cm, with additional pre-sowing or post-sowing rolling with a ring-spur roller KKSH. Sowing was carried out at a depth of 10 cm with stable heating of the soil in three periods: the first at 8–10 °С, the second at 10–12 °С, and the third at 12–14 °С. As a result of evaluating the influence of various factors, it was found that under favourable conditions, the highest seed productivity of soybean plants (1.91–1.96 t·ha−1) was formed after treatment with the stratifier PRSM-5 at the first sowing period and at the second sowing period after chisel ploughing with additional soil compaction. In dry weather conditions, pre-sowing treatment with a stratifier PRSM-5 had an advantage in seed productivity by 7–12% compared to ploughing with a chisel plough PCH-2.5.