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Depletion of soil fertility due to decrease in soil organic matter content represents a considerable problem in both developed and undeveloped countries. This paper deals with the comparison of compost (Cp) and mineral nitrogen fertilizer (NF) application on selected soil parameters which indicate state of soil environment, its health and quality. The main objectives of this study were (a) to investigate influence of Cp and NF application on total nitrogen (TN) and carbon (TC) content in soil (b), to determine positive/negative effects of Cp and NF application on microbial community (arbuscular mycorrhizal infection and basal respiration) in soil and production of winter wheat biomass (c), to provide recommendations on optimal dose of Cp in wheat cropping system. To demonstrate the above effect, the lysimetric experiment with seven variants was established in 2012 and then carried out for next three years. Each variant was prepared in triplicate with (Cp: 50 and 100 Mg/ha; NF: 140 kg/ha; Cp + NF: 50 Mg + 35 kg/ha; 50 Mg + 70 kg/ha and 50 Mg + 140 kg/ha) or without (control) addition of fertilizers. The positive effect ANOVA; Tukey's HSD) of Cp application on restoration of soil quality (increasing the TC and NT content in soil) and health (higher level of microbial activity) was found in all variants with application of Cp, in comparison with control variant. Moreover, variants where combination of Cp and NF was applied showed significant increase in biomass production and in content of CT and NT, compared to the variants without application of fertilizer or those with application of only NF. Based on these results, we conclude that the combined application of Cp and NF have a prerequisite for reducing negative effects of separate applications of mineral fertilizers. Above all, the potential negative effect of higher dose (100 Mg/ha) of Cp on soil health and quality was not found. [ABSTRACT FROM AUTHOR]

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Progress in the medical field is often shadowed by variability in microbial genetics, the capacity to adapt quickly and the resistance that microorganisms acquire to latest creations of the chemistry synthesis. In this context, the researchers` attention is drawn to obtaining the compounds that may have utility for medical, food or other fields of human interest, and which are obtained from medicinal and aromatic plants. The area of interest of the present study was the effects of alcoholic extracts obtained from the aerial parts and roots of some species of mint. Alcohol was used as control sample. The effect of the extract was reported at antibiotics microbial reaction. The antibiotics used were: ampicillin and cefotaxime for assessing antibacterial activity and nystatin for yeast activity. The microbial species tested were as follows: Staphylococcus aureusATCC 25923, Enterococcus faecalisATCC 29212and Candida albicans. Based on the results, it can be stated that the antimicrobial activity of the aerial parts of two species of mint is more pronounced. Thus, in the case of species M. smithiana, the extracts obtained from leaves and flowers exhibited a higher bacteriostatic effect. On the other hand, extracts from the leaves of M. spicata var. viridis had a stronger inhibition effect on the microbial cultures tested. [ABSTRACT FROM AUTHOR]

The aim of this work was to describe an impact of erosion and deposition processes on soil properties and consequently on a microbial activity and CO2 emission. Study was performed on morphologically diverse study site in loess region of Southern Moravia, Czech Republic. The original soil type was Haplic Chernozem, which was due to erosion changed into Regosol (steep parts) and Colluvial soil (base slope and the tributary valley). The grab soil samples were taken from topsoil at 5 locations of the selected elevation transect and also from the parent material (loess). The basic soil properties were measured in the laboratory: pHKCl, pHH2O particle size distribution, oxidable organic carbon content, carbonates content and electric conductivity. Bulk density, porosity and soil particle density were also determined. Colony-forming units per gram of dry soil (CFU) were analyzed. Wet and also dry soil samples were measured 24 hours in the laboratory using the LCi-SD portable photosynthesis system with soil respiration chamber. The maximal net CO2 exchange rate (NCER), average NCER between 11:00 to 16:00 o'clock and NCER at 19:00 o'clock were evaluated. The net H2O exchange rates were also assessed. In general, the microbial activity and soil respiration increased with increasing organic matter content, salinity and particle density. The largest values of CFU were measured on topsoil at the upper part of the transect, which was only slightly impacted by erosion. The lowest values of the microbial activity and soil respiration characteristics were obtained on topsoil at the steepest and heavily eroded parts of the transect and on the parent material. Results showed close correlation between the CFU and following soil properties: salinity (R=0.90), pHKCl (R=-0.97), pHH2O (R=-0.95), oxidable organic carbon content (R=0.96), carbonates (R=-0,89), clay content (R=-0,91) soil particle density (R=-0.90), bulk density (R=-0.94) and porosity (R=0.94). Similar correlations were found between soil respiration's characteristics on wet soil samples and soil characteristics. Close correlations were found also between CFU and maximal NCER (R=0,84) or average NCER (R=0,94) measured on wet soil samples. Results show that microbial potential expressed using colony forming units (CFU) and soil respiration characteristics could be used as an indicators of soil degradation due to erosion. [ABSTRACT FROM AUTHOR]