Effectiveness of urea-ammonia liquor KAS-32 and compound NPK fertilizer in linseed flax growing with minimal tillage in the Salair zone

Abstract

Of the major nutrients, linseed flax consumes and removes more nitrogen than other nutrients. Pre-sowing application of urea-ammonia liquor KAS-32 in rates of 100 and 150 L ha together with seedbed application of compound NPK fertilizer (diammophoska) (100 kg ha) contributed to greater nitrogen consumption. In seeds, on two-year average, it was 3.38-3.74% compared to 3.19% in the control; the potassium content at 0.65% in the control for the variants with KAS-32 was in the range of 0.54-0.77%, at 0.73% for the combination of N₇₄P₂₆K₂₆, amounting to 0.54% for N₅₃P₂₆K₂₆. The phosphorus level was in the range of 0.50-0.53% compared to 0.48% in the control. At the same time, the content levels of nitrogen and phosphorus in straw were lower, and potassium content was higher than in linseeds, respectively 0.53-0.79%, 0.065-0.9% and 0.88-1.08% compared to 3.19-3.74, 0.48-0.65 and 0.54-0.77%. The experiments showed the positive effect of fertilizers applied on such basic elements of the yield formula. In the variants with urea-ammonia liquor KAS-32, the two-year average plant density was 331-341 pcs m² compared to 272 in the control; the number of capsules was 13.8-13.9 pcs per plant compared to 9 pcs, or it was 1.4-1.42 times higher. Linseed yields increased from 1.28 t ha to 1.76-1.85 t ha, or by 37.5 and 44.5%. The protein content increased from 18.5 to 20.3-21.9%, and the oil content increased from 46.7 to 46.2-47.8%. One seedbed application of compound NPK fertilizer (diammophoska) provided high oil accumulation of 50.6 and 44.6% on both years and on two-year average - 47.6%. The cost recovery of 1 kg of primary nutrient ranged from 2.09 kg in the variant with of compound NPK fertilizer (diammophoska) and 4.52–4.57 kg in combinations with urea-ammonia liquor KAS-32.