Formation of seed productivity of Melilotus albus crops under the influence of agrotechnical and biological factors in the conditions of climate change

Abstract

Goal. To determine effective agrotechnical and biological factors to ensure the formation of the maximum level of seed productivity of Melilotus Albus Medik under climatic changes in the conditions of the Southern Steppe of Ukraine. Methods. Field — to establish regularities of growth and development of plants in natural conditions; visual-phenological — to fix dates of occurrence and duration of interfacial periods; measuring-weight — to carry out morphophysiological analysis and determine biometric indicators and seed productivity; mathematical-statistical — to verify the received data by means of dispersion analysis and estimate the reliability of results. The object of research was the Melilotus albus of the Pivdennyi variety. Results. The study was conducted in 2023–2025 on the experimental field of the Institute of Climate Smart Agriculture of the NAAS (vil. Khlibodarske, Odesa oblast). The soil of the experimental field was southern heavy-clay chornozem. A 3-factor field experiment was laid down (factor A — the method of basic tillage: plowing to a depth of 27–30cm, deep loosening to 22–24 cm, disking to a depth of 12–14 cm; factor B — treatment with biologic preparations, without treatment, treatment with preparations Kvantum SiAmin, Nertus Miks 400, PMK-U “Universalnyi”; factor C — the phase of plant development: the beginning of branching, the beginning of branching + budding). Due to feeding with biological preparations using various schemes and methods of soil cultivation during 2023–2025, on average, 0.71 t/ha of seeds were obtained. According to factor A (soil cultivation method), the highest yield of seeds (0.78 t/ha) was achieved during plowing to a depth of 27–30 cm. The use of loosening to a depth of 22–24 cm made it possible to obtain an average of 0.73 t/ha of seeds; disking to a depth of 12–14 cm contributed to the production of 0.63 t/ha. According to factor B (treatment with biological preparations), the highest yield of seeds (0.74 t / ha) was achieved by feeding with PMK-U “Universalnyi”. With the use of Nertus Miks 400, the yield of seeds averaged 0.73 t / ha, Kvuantum SiAmin — 0.72 t / ha. According to factor C (phase of plant development), the highest yield of seeds (0.72 t/ha) was obtained by conducting 2 foliar feedings in the phases of the beginning of branching and budding. With foliar feeding in the phase of branching onset, this indicator was at the level of 0.71 t/ha. Conclusions. The highest productivity indicators in the experiment (0.82 t/ha) were obtained for plowing to a depth of 27–30 cm and 2 feedings with PMK-U “Universal” in the phases of beginning branching and budding.