Effectiveness of Foliar Top Dressing of Flax with the Drug Controlit-Si on Different Backgrounds of Mineral Nutrition in the Conditions of the Central Non-Chernozem

Abstract

The responsiveness of flax to mineral fertilizers and foliar top dressing with an aqueous solution of the drug Controlfit-Si on sod-podzolic medium loamy soil was studied. It is shown that the reaction of flax to mineral fertilizers depended on the hydrothermal environmental conditions, doses and the ratio of nutrients. Excessive humidity and arid conditions negatively affected the productivity of crops. Foliar top dressing of plants with the drug Controlfit-Si leveled the negative impact of adverse weather conditions, increased the responsiveness of plants to mineral fertilizers, contributed to a more complete use of nutrients from fertilizers. On average, for 3 years on the backgrounds of full mineral fertilizer, top dressing increased the yield of flax straw by 25–30% with the best effect against the background of N48P48K48 (4.03 t/ha). Top dressing did not have a positive effect on the yield of flax seeds. It took 13.8 kg N, 5.9 kg P2O5 and 10.7 kg K2O to form 1 ton of flax crop with the appropriate amount of seeds, regardless of plant nutrition conditions.