Changes in flax yield and quality in response to various mineral nutrition.

The researchers of Russian State Agrarian University, Moscow Timiryazev Agricultural Academy in 2013-2016 conducted a long-term stationary experiment to study chemical and toxicological properties of fiber flax, Voskhod variety, growing on sod-podzolic soil in the soil and climate of the Moscow region. Test plots were selected with following crop rotation options: without fertilizers, without liming; without fertilizers, with liming; N100P150K120 (kg a.i./ha), without liming; N100P150K120, with liming; N100P150K120 + manure 20 t/ha, without liming; N100P150K120 + manure 20 t/ha, with liming. The agro-climatic conditions of the growing seasons during the research years did not have a negative impact on the growth and development of fiber flax, the hydro-thermal index was 1.1 in 2013, -1.05 in 2014, 1.5 in 2015, and 1.5 in 2016. The maintained crop rotation and the introduction of a full range of mineral and organic fertilizers has been found to contribute to high yields of flax in terms of fiber (18.5-18.9 hwt/ha) and seeds (7.9-8.3 hwt/ha). The seeds contain 16.9-19.5% protein and 33.5-39.4% lipids. The yield of flaxseed oil from seeds ranged from 19.5-35.7% on average for different variants of the experiment. The peroxide number index was 2.5-1.5 mg-eq O2/kg, the acid number index was 1.1-1.9 mg KOH/g, which corresponds to obtaining high-quality linseed oil in compliance with quality standards for all variants of the experiment.