FORMATION OF SPRING CAMELINA YIELD DEPENDING ON YEAR CONDITIONS, VARIETAL CHARACTERISTICS AND NUTRITION OPTIMIZATION IN THE SOUTHERN STEPPE OF UKRAINE

Abstract

The article presents research results on the impact of varietal characteristics, weather conditions, and nutrition optimization on the yield level of spring camelina (Camelina sativa L.) seeds under the Southern Steppe of Ukraine conditions. The experiments were conducted in 2023–2025 on southern chernozem at the Mykolaiv NAU Educational, Scientific and Practical Center. The 0–30 cm soil layer contained 2.9–3.1% humus, 20–25 mg/kg available nitrogen, 40–45 mg/kg P2O5, and 370–520 mg/kg K2O. The experiment design included three factors: variety (factor A) (Stepovyi-1, Mirazh), seed pre-sowing treatment (factor B) (treatment with water and the biopreparation Azotofit), and nutrition optimization (factor C) (no fertilizers; N30P30K30; N30P30K30 + foliar feeding with Mikro- Mineralis Oilseed and Boroplus; N15P15K15; N15P15K15 + foliar feeding). The experiment was four-replicated; the accounting plot area was 50 m², the total plot area was 80 m². The results showed a significant impact of all factors and their interactions on crop productivity. On average over three years, the lowest seed yield was obtained in the control: 1.09–1.25 t/ha for Stepovyi-1 and 1.16–1.36 t/ha for Mirazh. Applying the full rate of mineral fertilizer (N30P30K30) increased yields to 1.33–1.52 and 1.48–1.64 t/ha, respectively. The maximum yields were achieved under optimized nutrition (N30P30K30 + foliar feeding): 1.51–1.72 t/ha for Stepovyi-1 and 1.60–1.81 t/ha for Mirazh. Reducing the fertilizer rate by half (N15P15K15) provided yields of 1.27–1.46 t/ha; combining this with foliar feeding increased the yield to 1.40–1.63 t/ha. Seed pre-sowing treatment with Azotofit also increased yield, ensuring an additional 0.15–0.20 t/ha in all variants, and up to 0.21 t/ha combined with complete fertilization and foliar feeding. These results were achieved due to the activation of nitrogen-fixing bacteria, improved nitrogen nutrition, and enhanced plant resistance to stress conditions. It was also found that the seed yield of spring camelina significantly depended on the variety, pre-sowing seed treatment, and nutrition optimization. The highest productivity was obtained in both Stepovyi-1 and Mirazh varieties when combining mineral fertilizers with foliar feeding using Mikro-Mineralis Oilseed and Boroplus, which ensured the maximum yield of 1.51–1.81 t/ha.