Microbial inoculants as a means of improving soil and crop yields

Abstract

The article presented the results of studies of the influence of microbial inoculants Rhizobium japonicum and Azospirillum brasilense on the growth and development of soybean (Glycine max) at the initial stages of its development. The study was conducted on three experimental plots: a control plot without treatment, a plot with Rhizobium japonicum inoculum and a plot with Azospirillum brasilense inoculum. The main indicators were evaluated: plant height, number of leaves, root system development and total biomass at different stages of plant growth, as well as laboratory analysis of nitrogen content in plant tissues. The results of the study showed that the inoculants had a significant impact on all measured parameters compared to the control plot. In particular, the plants in the plot with Rhizobium japonicum showed 50% higher growth and development of the root system, which was confirmed by the formation of root nodules responsible for nitrogen fixation. Azospirillum brasilense also improved plant growth and root system development, but its effect was less pronounced compared to Rhizobium japonicum. Nitrogen content analysis showed that plants in the Rhizobium japonicum plot had 45% higher tissue nitrogen content compared to the control plot, indicating effective nitrogen fixation. In plants treated with Azospirillum brasilense, the nitrogen content was also 25% higher, but without nodule formation, the effect was less pronounced. The aim of the study was to evaluate the effectiveness of microbial inoculants in improving plant growth and development in the early stages of vegetation, to investigate their effect on root system productivity, nitrogen uptake and total plant biomass, and to determine the optimal conditions for maximising the impact of inoculants in agricultural conditions. The results emphasised the importance of using microbial inoculants to increase soybean productivity and resistance in the early stages of its development. The application of Rhizobium japonicum provided a greater increase in biomass, root system and nitrogen assimilation, which makes this inoculant more effective than Azospirillum brasilense