Biological products as factors for increasing soybean productivity

Abstract. In 2021–2023, in the forest-steppe zone of North Ossetia – Alania, research was carried out on the use of biological products (growth regulator “Giberelon” and microfertilizer “Ul’tramag Kombi”) on soybean crops of Vilana, Irbis, Vita varieties. The purpose of the work is to improve the technology of soybean cultivation, aimed at improving productivity and grain quality through the use of biological products. Scientific novelty. For the first time in the foothill zone of the republic, the influence of biologics (growth regulator and micronutrients) on photosynthetic activity, the size and quality of soybean crops of various ripeness was studied. Methods. The object of research was three high-yielding soybean varieties - Vilana, Irbis, Vita (breeding of the Federal Research Center of the V. S. Pustovoit Research Institute of Oilseeds). Among the biological products used were "Giberelon" (70 g/ha), a plant growth stimulator based on gibberellic acids; "Ultramag Combi" (2 l/ha) – a concentrated complex micronutrient for leafy top dressing of cereals. Observations and records were carried out according to generally accepted methods of field experience. Results. It has been established that the use of biological products “Giberelon” and “Ul’tramag Kombi” increases the symbiotic activity of soybeans and the amount of fixed nitrogen in the air. During the growing season, the largest number of active nodules were formed in plots where plants were treated with “Ul’tramag Kombi” microfertilizer. With the use of “Ul’tramag Kombi” microfertilizer, the mass of nodules also increased by 18.7–19.9 g compared to the control. The biological products used stimulated plant growth, where the highest plant height was noted for varieties ranging from 79.1–115.1 cm. The yield of soybean crops using the growth regulator “Giberelon” (with an application rate of 70 g/ha) increased by 0.13–0.25 t/ha, with the use of “Ul’tramag Kombi” microfertilizer (with an application rate of 2 l/ha) – by 0.28–0.47 t/ha. The average level of profitability for all studied varieties of experimental variants was 65.25 %, which is 28.75 % higher than the control variants.