The balance of organic matter and soil nutrients, depending on fertilization level of soybean varieties

Belgorod State Agricultural University named after V. Gorin, 308503 Belgorod, Russian Federation

^* Corresponding author: kotlyarovaeg@mail.ru

Abstract

The purpose of the research is to study the effect and interaction of straw-litter compost (20 t/ha), ammonium nitrate (30 kg/ha N) and microfertilizer Azosol 36 Extra (2 times 2 l/ha) on the fertility indicators of typical chernozem for soybean cultivation in the southern forest-steppe of the Central Chernozem region. It was found that the increase in fertilization level based on the use of compost contributed to the positive dynamics of organic matter and macronutrients, the formation of higher yields, protein content and collection. The largest increase in organic matter in the soil was in the variants of joint use of compost and ammonium nitrate – 0.52-0.68%. The combination of compost and ammonium nitrate, as well as the complex application of mineral fertilizers, maintained a positive balance of easily hydrolyzed nitrogen in the soil from 3.3 to 8.2 mg/kg. Perhaps, the early-ripening soybean variety Lantsetnaya mainly used nitrogen of mineral fertilizers for crop formation, while the mid-ripening variety Belgorodskaya 48 is more responsive to the use of compost. The introduction of compost also caused an increase in mobile phosphorus content in the soil by 36-47 mg/kg and the exchangeable potassium by 5.4-43 mg/kg. This contributed to the transfer by grouping to a higher gradation - to a high class of supply in terms of the content of both mobile phosphorus (163-196 mg/kg) and exchangeable potassium (125-168 mg/kg).