Influence of nitrogen fertilization on the elements of crop structure and productivity of spring barley

Abstract

The purpose of the research: to evaluate the productivity of different varieties of spring barley in farm conditions and to establish the optimal doses of nitrogen fertilizers for fertilizing. Research methods: laboratory, field, laboratory and field mathematical and statistical. Climate change, the shortage of organic fertilizers and the high cost of mineral fertilizers once again confirms the importance of the issue of optimal nutrition of spring barley plants. The research on the effectiveness of nitrogen fertilization for the formation of high productivity of spring barley was conducted during 2021–2022 under the conditions of Organic-D LLC on gray forest, medium loamy soils with a slightly acidic reaction of the soil solution. Mid-season spring barley varieties of domestic selection Lofant, Hetman, Vakula and Helios were used in the research. Research results. We have found that the application of nitrogen fertilizers significantly affects the formation of elements of the yield structure and productivity of the studied spring barley varieties. Characterization of the elements of the yield structure, such as the number of grains in the ear and the weight of 1000 grains depends on the biological characteristics of the varieties, growing conditions and the use of nitrogen fertilizers. The highest value of the weight of 1000 grains was observed in the variant with the application of nitrogen fertilizers at a rate of 60 kg. d.p. in the tillering phase of spring barley – Lofant – 42.1 g, Hetman – 41.8 g, Vakula – 41.0 g and Helios – 42.5 g. The number of grains in the ear of the studied spring barley varieties averaged 20.9 pcs. for two years in Lofant, 21.0 pcs. in Hetman, 22.0 pcs. in Vakula and 23.4 pcs. in Helios. The use of nitrogen fertilizers at the rate of N35 provided an increase in the number of grains in the ear by 1.0, 1.1, 1.1 and 2.3, at the rate of N45 by 1.6, 2.9, 2.5 and 4.4, and at the rate of N60 by 2.5, 3.8, 4.2 and 5.8, compared to the control variant (without fertilization). Conclusions. Thus, the use of nitrogen fertilization on spring barley crops can improve the complex of economically valuable traits and significantly increase the yield. The greatest increase in grain yield (1.96 t/ha) of the studied spring barley varieties compared to the control (without fertilization) was obtained in the variant with the use of nitrogen fertilization at a rate of 60 kg of d.p. per 1 ha. The yield level of the studied varieties on this fertilization variant, on average for two years of research, was Lofant – 3.85 t/ha, Hetman – 4.78 t/ha, Vakula – 4.62 t/ha and Helios – 4.84 t/ha.