Yield and water consumption of sunflower in the conditions of Western Polissia depending on soil liming and fertilization

Abstract

Goal. To determine the influence of the fertilizer system in combination with liming on the yield and water consumption of sunflower on the low-fertile sod-podzolic cohesive sandy soil in the conditions of Western Polissia. Methods. The study was conducted in 2022–2024 in a stationary field experiment of the Institute of Agriculture of Western Polissia of NAAS using the following methods: field (studying the effect of liming and mineral fertilizers on sunflower yield), laboratory (determining the actual soil moisture), calculation (calculating the reserves of productive moisture and water consumption), statistical (conducting dispersion analysis). Experimental data were processed using Microsoft Excel 2016 and Statistica 10.0 computer programs. Results. The highest yield of sunflower seeds (2.94 t/ha) was obtained against the background of applying 1.0 Ng dose of dolomite flour (CaMg(CO3)2) with mineral fertilizers in a dose of N110P65K105, and two foliar feedings with micronutrients. In the case of using N60P60K90 against the background of applying a 1.5 Ng dose of CaMg(CO3)2, the seed yield increased by 7.9% compared to a 1.0 Ng dose of meliorant. The use of the same dose of limestone flour (CaCO3) resulted in a 6.0% reduction in seed yield. Due to the complex use of ameliorants and fertilizers, the total water consumption of sunflower crops increased by only 2–3% compared to the control; however, the water consumption ratio decreased by 1.5–2.3 times, which indicated the extremely important role of optimizing the fertilizer system on low-fertile sod-podzolic cohesive soils in improving water consumption efficiency. Conclusions. The use of liming in combination with mineral fertilization provided 1.13–1.68 tons/ha higher yield of sunflower compared to the non-fertilized background. It was proved that balanced nutrition was a necessary condition for high efficiency of the technology, since nitrogen fertilizer provided only 0.70 t/ha of yield increase. The use of fertilizer N110P65K105 in a dose established according to the standards for the removal of nutrients for the formation of 3.0 t/ha of the main and the corresponding amount of by-products, against the background of 1.0 Ng dose of CaMg(CO3)2, provided that micronutrients were applied twice, contributed to rational water consumption: with a slight increase in total water consumption (by 3%), the water consumption for the formation of the crop unit decreased to 1480 m3/t compared to 3341 m3/t in the control. This indicated a significant increase in the efficiency of moisture consumption and the possibility of its more economical use when optimizing the fertilizer system of the culture.