Вплив доз і способів унесення азотних добрив на врожайність та якість зерна пшениці озимої

Abstract

Goal. To establish the optimal ratio of sulfur and nitrogen in the composition of mineral fertilizers for fertilizing Sudan grass in conditions of unstable moisture during the growing season. Methods. The field experiment was carried out on typical heavy loam chornozem of the State Enterprise “SI “Hrakivske” of the NSC “ISS named after O.N. Sokolovskyi” (Kharkivskyi district, Kharkiv oblast), where the change in the NPK:S ratio in the composition of mineral fertilizers in crops of Sudan grass was studied; laboratory-analytical studies were performed under current state standards; statistical and mathematical analysis of the obtained data was carried out with the help of the STATISTICA 13 program. The indicators of the efficiency of use (NUtE) and absorption (NUpE) of nitrogen by plants were calculated. Results. With the pre-sowing application of sulfur with fertilizers at the rate of S20–S40 during tillering, the content of its mobile forms in the soil layer of 0–20 cm increased from 9 to 15–44 mg/ kg, which narrowed the ratio of available N:S forms from 3.3:1 to 2.5–0.8:1. This had a positive effect on the accumulation of moisture in plant tissues and the yield of green mass of Sudan grass. When applying N100P60K60S20, the maximum obtained yield of green mass was 52.2 t/ha compared to 39.4 t/ha without the sulfur component. The highest content of nutrients (N — 1.7%, P — 0.55%, K — 1.5%) in mowed green mass was observed when N100P60K60S20–40 was applied, which together with the increase in productivity increased the removal of nutrients by the crop by 1,1–1.5 times. Nitrogen efficiency indicators confirmed the expediency of adding sulfur to the composition of fertilizers, and its optimal dose on the background of N100P60K60 was 20 kg/ha. Conclusions. The addition of sulfur in the sulfate form to the composition of mineral fertilizers for pre-sowing application of Sudan grass on typical heavy loam chornozem optimized the nitrogen-phosphorus-sulfur nutrition of plants, contributed to the increase of irrigation of tissues, increased the efficiency of nitrogen use by plants and the profitability of fertilizers by yield. On the background of N100P60K60, the optimal rate of sulfur addition was S20; increasing it to S60 weakens the positive effect.