Soil microbiological activity in winter rye crops under different fertilisation systems and biopreparations

The aim of the study was to determine the effect of different fertilisation systems in combination with biological preparations on soil microbiological activity under winter rye crops in the Polissia region of Ukraine. The methodology was based on a field experiment conducted during 2019-2021 at the research plots of Polissia National University. Two fertilisation systems were used – biological and organo-mineral with different ratios of components (50:50 and 75:25) – as well as a mineral system for comparison. Soil microbiological activity was evaluated using the linen decomposition method at a depth of 0-20 cm, and the results were processed by analysis of variance. The study established that the highest levels of biological activity were observed under the organo-mineral system with an equal proportion of organic and mineral components, where microbial activity exceeded the control by 8-10%. It was demonstrated that the biopreparations Trichodermin, Organik D2M, and Mochevyn K No. 2 positively affected soil microflora development, enhanced enzymatic processes, and contributed to the stability of microbial communities. It was also found that, even without the application of mineral fertilisers, the use of biological preparations significantly increased microbial activity, whereas the mineral system maintained a lower but stable level of response. The generalisation of results confirmed the synergistic effect of combining organic and mineral nutrient sources, which ensured a balanced microbiological environment and sustained soil fertility. The practical value of the study lies in the potential use of the findings to optimise fertilisation systems and integrate biopreparations into cereal crop production technologies in the Polissia zone of Ukraine to enhance the ecological efficiency of agriculture