Comparative assessment of tank mixtures of the modern herbicides in cultivation of oil flax on leached black soil of the Western Ciscaucasia

Potential yield of the modern oil flax varieties is up to 2.5–3.0 t/ha, but in fact, in 2020, its average yield was equal to 0.81 t/ha in the Russian Federation and 0.86 t/ha тin the Southern federal district. One of the reasons of such low productivity of the crop is non-effective protection of sowings against weeds. We studied impact of tank mixtures of herbicides Tifi, WDG (0.025 kg/ha) + Miura, CE (1.2 l/hа); Magnum, WDG (0.01 kg/hа) + Miura, CE (1.2 l/hа); Sekator Turbo, OD (0.1 l/hа) + Miura, CE (1.2 l/hа) and Sekator Turbo, OD (0.1 l/hа) + Quickstep, OCE (0.8 l/hа) on oil flax productivity (the variety FLIZ bred at the V.S. Pustovoit All-Russian Research Institute of Oil Crops). The researches were conducted in a zone of unstable moistening on leach black soil of the Western Ciscaucasia in 2017–2020. Recommended doses of tank mixtures of the herbicides were applied in a phase of 5-6 pairs of leaves development of oil flax plants. In spite of the good water availability in years of the research, high air temperatures during flowering – seeds formation negatively influenced the crop productivity. Due to our results, on average for four years, treatment of oil flax plants with a tank mixture of the herbicides Sekator Turbo, OD (0.1 l/hа) + Quickstep, OCE (0.8 l/hа) allowed obtaining the highest yield – 1.17 t/hа, oil content in seeds – 45.5% and oil yield – 0.47 t/hа; there was fixed the high clear profit – 13,861 RUR/hа at profitability of 51%.