Influence of Technological Factors on the Formation of Quality Indicators of Black Cumin (Nigella sativa L.) Seeds under the Conditions of the Western Forest-Steppe

Abstract

Purpose. The purpose of our research was to assess the influence of methods of applying plant growth regulators on the chemical composition of black cumin seeds under the conditions of the Western Forest-Steppe of Ukraine. Methods. The study combined general scientific methods – hypothesis, observation, and analysis – with specialized ones, including analytical research methods and data from field experiments. Experimental data were processed using methods of mathematical statistics according to V. O. Yeshchenko. Results. The article presents the results of field and laboratory studies on the influence of different methods of applying plant growth regulators on a key technological indicator – the weight of 1000 seeds – and on the chemical composition of black cumin seeds (oil, essential oil, and protein content) when cultivated under the conditions of the Western Forest-Steppe. Based on three years of research, more effective plant growth regulators and methods of their application were identified in relation to the quality indicators of black cumin seeds. The significant and statistically substantiated influence of growth regulators on the weight of 1000 seeds, as well as on the fat and essential oil content of the seeds, was established. Conclusions. The optimal weight of 1000 seeds – 2.39 g – was obtained in the variant where the seeds were pretreated before sowing with the growth regulator Regoplant, which exceeded the control by 0.16 g. A slightly lower value (by 0.06 g) was obtained in the variant with foliar spraying using Vermistim D. The highest fat content in black cumin seeds – 36.9 % (2.9 % above the control) – was observed in the Regoplant treatment, while Vermistim D resulted in 36.5 % (2.3 % above control). Laboratory analysis showed that all tested preparations positively influenced the accumulation of essential oil in the seeds, ranging from 1.2 % to 1.5 %, while the control recorded 1.2 %. The Vitazym seed treatment variant showed a similar result to the control. The optimal essential oil content – 1.5 % – was recorded for pre-sowing seed treatment with Regoplant, exceeding the control by 0.3 %. Plant growth regulators led to a reduction in protein content in black cumin seeds by 0.6–1.7 %.