DURATION OF INTERPHASE AND VEGETATIVE PERIODS OF CORN HYBRIDS DEPENDING ON THE LEVEL OF MINERAL NUTRITION, 2021

The study investigated the influence of macro- and micronutrient applications on the growth and development phases of corn hybrids in 2021. Full emergence was observed on the 7th–8th day after sowing, regardless of macrofertilizer dosage. In some treatments, seed priming with YaraVita Teprosyn NP+Zn (5 L/t) and YaraTera Tenso Cocktail (0.15 kg/t) shortened the “sowing–emergence” period by one day compared to the control. The duration of the “emergence–flowering” stage depended on hybrid maturity group and fertilizer use, with differences of 3–5 days between medium-early and medium-maturing hybrids.

Combined micronutrient treatments did not reduce this period, while macrofertilizers extended it by 1–2 days. A similar trend was noted for the “emergence–milk maturity” stage: in the control, Amaros reached milk maturity in 76 days, Bohatyr in 77, KWS 381 in 84, and Carifols in 87 days. Application of N₉₀Р₆₀К₆₀ extended this phase by 1 day, and N₁₂₀Р₉₀К₉₀ by 1–2 days.

On average, milk maturity occurred 25 days after flowering. Micronutrient treatments did not alter this interval. In medium-early hybrids, the “milk–milk-wax maturity” and “milk-wax–wax maturity” stages lasted 10–11 and 11–12 days, respectively, while in medium-maturing hybrids they lasted 10–12 and 11–13 days.

Shorter grain maturity periods were observed in Amaros and Bohatyr, while longer ones were recorded in KWS 381 and Carifols. The total vegetation period was 98 days for Amaros, 101 for Bohatyr, 106 for KWS 381, and 109 for Carifols. Macrofertilizers extended vegetation by 1–2 days, whereas micronutrients had no effect.