Soybean productivity under different methods and systems of primary soil treatment in the second rotation of the crop rotation

The aim of the research is to increase the seed yield and protein and oil yield of soybean by optimizing the methods and systems of primary soil tillage in the second rotation of the crop rotation (with the rotation of crops soybean, winter wheat, spring rapeseed and spring barley) in the conditions of the forest-steppe of the Central Federal Region of Russia. The research was conducted in 2019–2022 at the Lipetsk Rapeseed Research Institute – a branch of V.S. Pustovoit All-Russian Research Institute of Oil Crops. In the field experiment on leached medium-deep heavy loamy chernozem four systems of primary soil treatment, which had the conventional names: moldboard-surface, moldboard-surface with deep loosening, moldboard-surface with shallow loosening and minimal plowing (non-moldboard) were studied. Studies were conducted according to generally accepted methods and State Standards. It was found that the quality of soybean seeds by the content of crude fat and protein in the variants of the experi-ment changed insignificantly. On the average for the years of the second rotation of the crop rotation, higher and relatively equal yield of seeds, protein and oil of this crop was provided by moldboard-surface (plowing for soybean and spring rapeseed, surface tillage for winter wheat and spring barley) and moldboard-surface with deep loosening (deep subsurface loosening for soybean, surface tillage for winter wheat, spring barley and plowing for spring rapeseed) systems of the primary soil treatment. In other vari-ants of the experiment, where shallow or surface tillage was carried out directly under soybean at its cor-responding systems, all the analyzed indicators of productivity decreased significantly and almost equally.