Yield and quality of seed of sunflower hybrids (Helianthus annuus L.) depending on the fertilizer system

Abstract

The results of the research conducted at the Poltava State Agricultural Research Station named after M. Vavylov in 2022–2023 showed a positive effect of the fertilizer system on the yield and seed quality of sunflower hybrids of different maturity groups. The combination of foliar application with urea at the rate of 10 kg ha-1 and mineral fertilization with N32P32K32 increased the yield of hybrids Kadet, Yarylo, Vyrii at the level of 3.11, 2.75, 3.18 t ha-1, which more than in the control (without any fertilizers) by 0.41 t ha-1, 0.38 t ha-1 and 0.47 t ha-1, respectively. A significant increase in yield (0.32–0.42 t ha-1) compared to the control was also observed in the variant where foliar application with Potassium humate (0.4 l ha-1) was carried out at a similar dose of mineral fertilizers. In this variant of fertilization it was obtained the average yield of the hybrids Kadet – 3.06 t ha-1, Yarylo – 2.69 t ha-1, Vyrii – 3.13 t ha-1 or 0.02–0.10 t ha-1 less than the previous variant of fertilizers use. In the variant of combination of mineral fertilization (N12P52), and foliar plant application with urea (10 kg ha-1) or Potassium humate (0.4 l ha-1), the yield of hybrids was in the range of 2.55–3.01 t ha-1, which exceeds the control (without fertilizers) by 0.14–0.30 t ha-1. In the experiment, the oil content in the kernel of sunflower seeds varied depending on the dose of mineral fertilizers and the type of foliar plant application. It was found that the greatest amount of oil in the seeds (51.4 %) of the early-maturing hybrid Kadet and the mid-early maturing hybrid Yarilo was obtained by foliar application of Potassium humate stimulant at a dose of mineral fertilizers N32P32K32. The maximum oil content in seeds of the mid-maturing hybrid Vyrii (51.0 %) was observed in the variant of combination of foliar application with urea (10 kg/ha) and mineral fertilization with N12P52. The combination in the sunflower plant nutrition system the main application of mineral fertilizers and foliar application of sunflower plants in the phase of 5–6 pairs of leaves led to the highest oil yield per unit area (1229–1422 kg ha-1).