Effectiveness of increasing doses of mineral fertilizers in the cultivation of spring barley of the Novichok variety

The results of the research were obtained in 2019-2020 on sod-podzolic middle-loam soil in the conditions of EuroNorth-East of the Russian Federation. There were studied 18 variants of increasing doses of mineral fertilizers in the range from 30 to 150 kg of active ingredient per hectare. Under the conditions of 2019 growing season, nitrogen fertilizers influenced the value of yield of Novichok barley variety to a greater extent (Y = 0.67 - 0. 11x 2 + 1.33x, R 2 = 0.92), in 2020 - phosphorus fertilizers (Y = 1.48 - 0.02x 2 + 0.48x, R 2 = 0.99). On average, over 2 years of research, the yield in the control variant without the use of fertilizers was 0.87 t/ha. Yield increase of barley grains because of enlarged fertilizer doses ranged from 1.38 to 3.90 t/ha. The payback of 1 kg of active ingredient of fertilizers with increase of barley yield decreased due to enlarged doses: from 15.3 (N 30 P 30 K 30 ) to 8.3 kg (N 150 P 150 K 150 ). On average for two years of the research the increasing doses and ratios of mineral fertilizers had no significant effect on technological properties of spring barley seeds. The content of crude protein in grain grew with increase in fertilizer doses (r = 0.55). To obtain grain of the 2nd class of quality it is necessary to apply not less than 90 kg of active ingredient/hectare of ammonium nitrate. According to the content of crude cellulose, the 1st class of grain quality has been obtained, and this indicator did not depend on the application of fertilizers. High profitability of cultivation of the Novichok spring barley variety (from 54.2 to 59.1 %) has been recorded by application of mineral fertilizers in doses N 60 P 60 N 120 , N 60 P 60 K 60 and N 120 P 120 K 120 .