Influence of growing conditions on the qualitative and quantitative composition of oil from different flax varieties

The article presents the results of studies of the qualitative and quantitative oil composition of varieties of oil flax in the Carpathian and Steppe conditions. Field studies were carried out during 2018–2020 at of the educational and research site of the Drohobych State Pedagogical University (DSPU) named after Ivan Franko (Lviv region, Carpathian zone) and the research site of the Institute of Oilseed Crops (IOC) of the National Academy of Agrarian Sciences of Ukraine (Zaporizhzhia region, Steppe zone). The researches were carried out according to the generally accepted methodology and recommendations. The varieties of IOC NAAS breeding (Vodogray, Vogni Dniprogesu, Zhivinka, Zaporizhzhia Bogatyr, Svitlozir, Pivdenna nich) were sown on two–meter plots using the standard row–by–row method with row spacing of 15 cm in 3 replications with a seeding rate of 100 seeds per 1 linear meter. During 2018–2020, weather conditions for research in Carpathian and Steppe zones differed in the amount of precipitation and temperature regime both from each other and the average annual indicators, which affected the oil content and its fatty acid composition. The research findings showed that the average oil content in oil flax seeds under the conditions of the Carpathian region was 44.91%, and under the conditions of Steppe – 46.84%. The differences between individual genotypes for these indicators given the Carpathian region ranged from 40.14% in the Pivdenna nich variety (2019) to 48.85% in the Svitlozir variety (2018), given the Steppe region– from 41.86% in the variety Pivdenna nich (2018) up to 49.81% in Vodogray (2019). Depending on growing conditions, fluctuations in oil content within one variety reached 2–4%. It has been established that all genotypes (except for the variety Svitlozir, the oil content has not changed) are able to accumulate more oil in seeds when grown in the Steppe zone compared to the Carpathian zone. The fatty acid composition of flax seeds did not differ significantly both over the years and from the soil–climatic area of growth. The maximum amount of linolenic acid was found in the varieties Vodogray and Svitlozir, the minimum – in the variety Zhivynka. In the Carpathian zone, there was a change in the distribution between oleic and linolenic acids towards an increase in linolenic and a decrease in oleic acids compared to the samples grown in the Steppe zone. It has been established that the most influential factors of the qualitative and quantitative oil content are the variety genotypee and the soil and climatic conditions of cultivation.