EFFECTIVENESS OF SOYBEAN INOCULATION WITH NODULE BACTERIA AND MYCORRHIZAL FUNGI IN THE CONDITIONS OF THE RIGHT BANK FOREST STEPPE OF UKRAINE

The relevance of this study is determined by a complex of factors that shape soybean grain productivity – the effectiveness of symbiotic systems formed with nodule bacteria and mycorrhizal fungi, the activity of growth processes and the formation of vegetative organs by soybean plants, as well as their adaptive plasticity under the influence of various external factors. The purpose of this study was to investigate the morphobiometric characteristics of soybean plants, the productivity of the crop after pre-sowing treatment with biological preparations Rhizoline, Mycofriend, and Rhizosave. This paper presents the results of research on the use of soybean seed treatment with biological preparations to improve the growth and development of soybean plants and increase crop productivity. Field, laboratory, mathematical-statistical, and calculation methods were employed for this study. It was found that seed inoculation positively affects the leaf surface area in the budding phase, it increased from 5,313 cm2 in the control to 6,426 cm2 with the Rhizoline + Rhizosave + Mycofriend option, and in the phase of pod formation, respectively, from 8,704 cm2 to 1,113 cm2 . The joint use of Rhizoline + Mycofriend + Rhizosave preparations most contributed to the increase in the mass of the root with nodules (+0.95 g), the number of nodules on the plant (+32 pcs), and the mass of nodules from the plant (+0.3 g). It was found that a comparable situation occurred during the phase of bean formation. The regularity of yield growth during the years under study showed that the average increase in yield varied from 0.41 t/ha with Rhizoline + Rhizosave inoculation to 0.6 t/ha with the combined use of Rhizoline + Rhizosave and the mycorrhizal preparation Mycofriend. It was substantiated that under appropriate conditions, the intensity of symbiotic nitrogen fixation increases thanks to nodule bacteria, as well as the absorption of water and nutrients by the root system of plants due to the activity of mycorrhizal fungi, the entry of amino acids, phytohormones, and vitamins into the plant, which positively affects the growth and development of soybean plants. The materials of this paper are of practical value for farmers in the development of new plant nutrition strategies involving biological preparations in the cultivation technology