| Abstract [eng] |
Microorganisms living in the soil affect soil quality and plant productivity. Microorganisms in the soil perform many important functions: break down organic compounds, fix nitrogen, nitrify, denitrify, dissolve phosphate, help plants get the necessary minerals and stimulate their growth. Although soil microorganisms are able to reproduce rapidly, adapt to the environment and remain viable in adverse conditions, it is important to monitor the abundance, diversity and activity of microorganisms in order to maintain soil quality and fertility. Various fertilizers are often used to stimulate fertility and replenish the soil with missing elements, but in most cases, chemical fertilizers are chosen. In order to reduce the use of inorganic fertilizers, an alternative solution can be fertilization by natural means - manure, peat, compost, intercrops or soil supplementation with microorganisms. However, an excessive amount of fertilizers can negatively affect both the soil itself and the populations of microorganisms. By performing various microbiological tests, it is possible to detect pathogenic microorganisms in time, monitor changes in the communities of microorganisms, their physiological activity or vitality. This study investigated the effect of different fertilizations (fertilization with chemical fertilizers, compost, peat, manure and, as a control sample, soil not fertilized at all) on soil microorganisms and pea growth with and without the addition of growth-promoting bacteria of the genus Rhizobium. Higher amounts of microorganisms, higher abundance, number of species in the community and physiological diversity of the community were found in initial samples 1, 2, 3, 4, 5. After harvesting peas, these parameters decreased in most cases in the studied soil samples. The highest total number of bacteria, spore-forming and nitrogen-fixing bacteria was found in soil sample 2 fertilized with compost. This sample also recorded the highest number of microbial species and the highest physiological diversity of the microbial community. The highest number of actinomycetes was found in soil sample 3, which was fertilized with peat. The highest amount of microscopic fungi and yeasts was found in soil 1 fertilized with chemical fertilizers. After evaluating the influence of Rhizobium bacteria on peas, it was found that the greatest effect was on seed germination and initial growth rate. In the post-harvest samples, the highest total bacterial count was found in the unfertilized 5A sample and the highest count of microscopic fungi in the manured 4A soil. The highest abundance of microorganisms, the number of species of microorganisms in the community and the physiological diversity were determined in sample 3A - in the soil fertilized with peat. |
