Effectiveness of sulfur-containing fertilizers in the cultivation of peas in the conditions of chernozem soils of the Kursk Region

In an experiment on typical deep, heavy loamy chernozem conducted in 2018–2020 in the Kursk FASC, the effect of various doses of sulfur-containing fertilizer NPKS(10–20–20–6) on the yield and quality of pea grain of the Pharaoh variety was studied in the following variants: 1 – control without fertilization, 2 – NPKS(10–20–20–6) at a dose of N20P40K40S12 from autumn for basic tillage + N20 (ammonium nitrate) in spring for pre-sowing cultivation, 3 – NPKS(10–20–20–6) at a dose of N30P60K60S18 from autumn for basic tillage + N30 (ammonium nitrate) in spring for pre-sowing cultivation, 4 – NPK(16–16–16) at a dose of N40P40K40 (250 kg/ha) from autumn for basic tillage, 5 – NPK(16–16–16) at a dose of N60P60K60 (375 kg/ha) from autumn for basic tillage. It was shown that in conditions of chernozem soils with a low level of sulfur availability (4.5 mg S/kg), its introduction into the soil as part of the complex mineral fertilizer NPKS(10–20–20–6) increased the yield of peas by 1.9–1.6 c/ha, the protein content in the grain – by 0.4–0.5% compared to the application of a complex mineral fertilizer without sulfur (NPK16–16–16). The use of sulfur-containing fertilizer NPKS(10–20–20–6) in pea crops was economically profitable: the net income from its application was 3 901–6 612 rubles/ha, the profitability level was 68.0–85.4%, with the values of these indicators in the control variant equal to 15 312 rubles/ha and 65.9%, respectively. Increasing the dose of sulfur-containing fertilizer NPKS(10–20–20–6) to N60P60K60S18 was not economically feasible.