The effect of increasing doses of mineral fertilizers on productivity and structural indicators of Raphael spring barley new variety

Abstract

Study of the effectiveness of the use of increasing doses of mineral fertilizers (N16P16K16...N120P120K120) was carried out in 2020-2022 in the conditions of the Ryazan region on dark gray forest heavy loamy soil of average fertility. The object of the research was a new variety of spring barley Raphael, included into the State Register of the Russian Federation for the Central (3) and Volga–Vyatka (4) Regions in 2022 (patent No. 12254). As the result of the research, there was revealed a positive trend for raising the yield of the Raphael variety resulted from the use of increasing doses of NPK (y = 0.1829x + 6.36, R2 = 0.8866). On average, over the years of the research, the minimum yield productivity (6.50 t/ha) was shown by the control variant (N16P16K16), the variant with application of high doses (N120P120K120) had the maximum productivity (7.40 t/ha). The yield increase by 0.6...0.9 t/ha was provided by mineral fertilizers in doses of N45P45K45...N120P120K120. The yield of barley per year with sufficient moisture supply during the growing season (HTC = 1.39) was 4.6-5.1 % higher than in dry years (HTC = 0.63-0.53). Structural analysis of yield indicates that during the experiment, the yield of this variety has been influenced by the length of the ear (r = 0.689), the number of grains in the ear (r = 0.467), the weight of grain per the ear (r = 0.715). Increasing doses of applied fertilizers led to an increase in the leaf surface area of plants and the height of the productive stems. The highest protein content in barley grain was observed in the variant with the use of N120P120K120 (on average 14.1 %), the minimum – with the application of N16P16K16 (on average 13.2 %). The calculation of economic efficiency showed that the highest conditional net income (69413 rubles/ha) and the level of profitability (187.1 %) with the yield of the new Raphael variety of 7.1 t/ha can be achieved by applying medium doses of fertilizers N45P45K45.