Evaluation of measures for biologization of nitrogen nutrition of oilseed flax in the conditions of the Southern Steppe of Ukraine

Abstract

The introduction of modern biological elements into the technology of growing oil flax, which includes the use of biological preparations with plant nutritional effects to improve growth and development conditions, is a direction for providing consumers with cleaner and healthier products. Purpose. Summarize the results of field research on the use of biological preparations of associative nitrogen fixation in modern oil flax production and to assess the prospects for introducing biological elements of technology when growing it in arid conditions of Southern Ukraine. Methods. During the collection and analysis of available scientific information, general scientific methods such as analysis, synthesis, abstraction, generalization, comparison were used. Field research was conducted in 2023–2025 on the basis of the Odessa State Agricultural Research Station Institute of Climate–Oriented Agriculture of the NAAS of Ukraine in a six–field crop rotation (peas – soft winter wheat – chickpeas – hard winter wheat – flax – millet) according to generally accepted methods and instructions. Research results. On average, over the years of research, it was found that the biological preparations Azotofit – r and Ecoriz have a positive effect on the formation of crop structure elements and yield, which ensures an increase in the number of pods per plant by 8.55 %, the number of seeds in one pod by 4.45–5.56 %; an increase in yield by 8.85 %–10.53 %. Applying nitrogen N15 increased the number of pods by 7.35 %; seeds – 1.90 %; increased yield by 6.50 %. Increasing the nitrogen rate to N30 and N45 provides an increase in the number of pods by 11.53–17.49 %; seeds by 5.39–6.03 %; increased yield by 17.26–27.35 %. Conclusions. The use of microbiological preparations of associative nitrogen fixation Azotofit–R (1 l/t) produced by “BTU–Center” and Ecoriz (1 l/t) of the Institute of Microbiology and Virology named after D. K. Zabolotny of the NAS of Ukraine when growing oil flax of the Vodograi variety contributes to an increase in yield by 0,94 and 0,79 c/ha. A positive effect of biological preparations on the elements of the crop structure has been established. Treatment of flax seeds with biological preparations Azotofit–r and Ecoriz is comparable to the application of mineral fertilizers at the rate of N20.6 and N18.2, respectively. The effectiveness of biological preparations depends on the weather and climatic conditions of the year.