THE INFLUENCE OF PRE-SOWING TREATMENT OF SEED AND EXTRA-ROOT NUTRITION ON THE DYNAMICS OF FORMATION OF THE LEAF SURFACE AREA OF SOYBEAN PLANTS

In modern agricultural conditions, the fertilization system is one of the most expensive technological methods of growing agricultural crops, including soybeans. In today's difficult conditions, there is an acute shortage and rising prices for various types of energy resources, including mineral fertilizers. The variability of climatic and weather conditions and the high cost of mineral fertilizers lead to the search for alternative approaches to the optimization of existing and the development of new technological methods of cultivation. This article presents the results of studies on the impact of biological preparations, namely the inoculants Bioinoculant BTU, Rizoline + Rizosev, Anderiz and biological fertilizers for foliar feeding Biocomplex BTU, Gumifrend and Helprost soybean on the formation of the leaf surface area and productivity of soybeans. Conducting field research involved studying the impact of pre-sowing seed treatment, foliar fertilization and their combination in order to determine the most effective model of their use. On the basis of the conducted observations and records, it was established that in the conditions of the right-bank forest-steppe on gray forest soils, the investigated preparations of biological origin had a direct effect on both the dynamics of the leaf surface area and the formation of productivity. In the experiment, the maximum leaf surface area of 42.1±6.8 thousand m2/ha was formed on the variant of the experiment where pre-sowing treatment of seeds with the BTU Biocomplex preparation and foliar feeding in the phase of the 3rd trifoliate leaf and budding with organo-mineral fertilizer Helprost soybean (2.5 l/ha), which is 11.0 thousand m2/ha or 35.3% more compared to the control. In addition, this variant recorded the highest grain yield of 3.31 t ha-1, which is 0.84 t ha-1 (34.0%) more compared to the control without seed inoculation and foliar foliar feeding.