Corn yield in the application of doses and forms of nitrogen fertilizers in the Shaulder irrigation massif of Turkestan region

Abstract

Nowadays, to obtain high and stable yields of agricultural crops, in addition to the creation and introduction of new high-yielding varieties, the use of various plant protection products, growth stimulants and biopreparations, the effective use of mineral fertilizers is a necessary agricultural technique. The purpose of this work was to study the influence of various doses and forms of nitrogen fertilizers on the dynamics of the accumulation of raw mass of corn plants, crop structure, yield, as well as the removal and normative consumption of nutrients on different salinization backgrounds in the Shaulder irrigation massif of Turkestan region. The obtained results showed that the best indicators were established in a slightly saline background than in an average saline one. On average, on a slightly saline background, the yield of corn grain, depending on the forms of nitrogen fertilizers at a dose of 80 kg / ha, varied in the range of 13.2-14.9 t/ha. At the same time, the yield gain from the use of various forms of fertilizers at the same doses of nitrogen amounted to 21.6-37.4 %. Against a medium-saline background, the option with the use of ammonium nitrate (variant 5) with an addition of 47.7 % nitrogen fertilizer to the phosphorus-potassium background. Regression models were obtained that accurately reflect the dependences of the grain yield and the elements of the corn crop structure on the total effect of nitrogen fertilizer (x1) and the degree of soil salinity (x2): Y = 18.429 + 0.2656x10.5 - 37.0995x2 with a high coefficient of determination - R2 = 0.954. On a slightly saline background, nitrogen removal by the corn grain harvest with the corresponding amount of by-products according to the experimental options varied from 282.9 kg/ha in the P80K80 option, to 370.1 kg/ha in the P80K80 + N120 option (ammonium sulfate), phosphorus – from 121.4 kg/ha in the P80K80 + N80 option (urea) to 160.7 kg/ha in the P80K80 + N80 option (ammonium nitrate), potassium – from 325.2 kg/ha in the P80K80 + N80 option (urea) to 413.7 kg/ha in the P80K80 + N80 option (ammonium sulfate). On a medium-saline background, nitrogen removal was in the range of 175.3–223.8 kg/ha, phosphorus - 67.4-89.6 kg/ha, potassium – 178.5-217.3 kg/ha. The utilization rate of nitrogen from fertilizers varied significantly depending on the doses and forms of nitrogen fertilizers and the degree of soil salinity.