Dependence of the leaf surface area, crop structure, and quality of sowing millet grain on nitrogen nutrition

Abstract

Goal. To analyze the dynamics of the formation of the assimilation surface of the leaf apparatus, high yield and quality of millet grain, depending on nitrogen nutrition. Methods. Field — to study the impact of doses of nitrogen fertilizers on the growth and development and yield of sowing millet; measuring-weight — to determine the area of leaves, yield, and structure of the crop; infrared spectroscopy — to determine the protein content in the grain; mathematical-statistical — for processing experimental data using Statistica 2013 software. Results. The study was conducted in 2024–2025 in a temporary field experiment at Uman National University. The soil of the experimental field was podzolized heavy-clay black soil. Research data on the intensity of fertilization of millet with nitrogen fertilizers, the influence of nitrogen fertilizers on the formation of the leaf surface, the structure and level of yield, and grain quality were provided. The positive influence of intensive nitrogen nutrition on the growth and development of the leaf apparatus, the yield, and quality of millet grain was fixed. Conclusions. The most effective dose of nitrogen fertilizers in millet crops was 80 kg/ha with the introduction of nitroamofoska N30P30K30 for plowing, 30 kg/ha of ammonium nitrate for pre-sowing cultivation, and 20 kg/ha of urea at the end of the shrubbery phase. The area of the leaf apparatus in the BBCH 60 phase was 36.6 thousand m2/ha, which was 15.4 thousand m2/ha more than at the control without fertilizers. With this dose of nitrogen fertilizers, the optimal structure of millet harvest was formed: the length of the panicle was 36.8 cm, the number of grains in the panicle was 488 pcs., the weight of 1000 grains was 8.1 g, and the weight of grains in the panicle was 4.0 g. By applying N80P30K30, the highest yield of millet grain was achieved — 4.40 tons / ha, which was 1.29 tons/ha more than the value in the control without fertilizers. In wet 2025, its grain yield was 1.05 tons/ha higher than in dry 2024. Intensive repeated fertilization with nitrogen fertilizers at a dose of 80 kg/ha provided the highest protein content in millet grain — 13.4%, which was 1.3% more than in the control without fertilizers. In dry 2024, the protein content in the grain was 2.4% higher than in wet 2025.