Formation of yield and seed quality of linseed varieties (Linum humile Mill.) in the conditions of the Western Forest Steppe of Ukraine

Purpose. To determine the peculiarities of yield and seed quality formation of varieties of linseed (Linum humile Mill.) in the conditions of the Western Forest Steppe of Ukraine. Methods. The research was conducted in 2020–2021 at the experimental field of the Khmelnytskyi branch of the Ukrainian Institute for Plant Varieties Examination (Trebukhivtsi village, Letychivskyi district, Khmelnytskyi region). Sowing was carried out in the second decade of April, the sowing rate was 8.0 million seeds per hectare. Subjects of the research were oil flax varieties ‘Orfei’, ‘Svitlozir’ and ‘Vodohrai’. The experimental design, evaluation of material, phenological observations and biometric measurements of plants, harvesting were carried out in accordance with the “Methodology for the qualification examination of plant varieties of the technical and fodder group for suitability for distribution in Ukraine”. The quality indicators of linseed were determined according to the “Methodology of qualification examination of plant varieties for suitability for distribution in Ukraine”. Results. The optimal conditions of the Western Forest Steppe of Ukraine contributed to the timely onset of the phenological phases of growth and development, as well as to the insignificant variation in the duration of the vegetation period (from 96 to 99 days) of the flax plants. Productivity was assessed using indicators such as the number of pods and the weight of seeds per plant. Under the condition of sowing on 25 April and the sowing rate of 8.0 million seeds per hectare, the highest yield was characterised by the variety “Svitlozir” (1.45 t/ha), the lo­west – ‘Orfei’ (0.8 t/ha). The varieties ‘Orfei’, ‘Svitlozir’ and ‘Vodohrai’ were evaluated by biochemical indicators and the content of crude protein, oil and fatty acids (palmitic, stearic, oleic, linoleic, linolenic, gondoic, eicosapentaenoic and erucic) was determined. Thus, ‘Orfei’ was characterised by the highest amount of protein in the seeds – 24.15%; ‘Svitlozir’ had an indicator of 22.74%; ‘Vodohrai’ – 22.26%. A high percentage of oil in the total dry matter was found in ‘Vodohrai’ – 45.6%, which is 2.19% more than in ‘Orfei’. The content of linolenic acid varied from 45.703 (‘Orfei’) to 48.261% (‘Svitlozir’) and erucic acid was not detected in any of the varieties during the study. Conclusions. The varieties ‘Orfei’, ‘Svitlozir’ and ‘Vodohrai’ were characterised by more than 35% oil content in seeds, which meets the requirements of State Standard 7577:2014 and ensures the quality of marketable oil flax products.