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The aim of the research was to evaluate the effect of three types of silver nanoparticles (AgNPs) with different physicochemical properties and silver ions delivered in the form of silver nitrate (AgNO3) at the concentration of 50 mg L−1 on germination and initial growth of monocots (common wheat, sorghum) and dicots (garden cress, white mustard). The AgNPs were prepared using trisodium citrate (TCSB-AgNPs), tannic acid (TA-AgNPs), and cysteamine hydrochloride (CHSB-AgNPs). They exhibited comparable shape, size distribution, and an average size equal to 15 ± 3 nm which was confirmed with the use of transmission electron microscopy. The electrokinetic characteristics revealed that CHSB-AgNPs have positive, whereas TCSB-AgNPs and TA-AgNPs negative surface charge. First, toxicity of the silver compounds was assessed using the Phytotestkit test. Next, after transferring seedlings to pots, shoot length, leaf surface, shoot dry mass, electrolyte leakage measurement, and photosystem II (PSII) efficiency were determined. AgNPs and silver ions delivered in the form of AgNO3 reduced root and shoots length of common wheat, sorghum, and garden cress; leaves surface of garden cress and white mustard; and shoots dry mass of white mustard. The positively charged CHSB-AgNPs and silver ions delivered in the form of AgNO3 showed the greatest inhibition effect. Moreover, silver ions and positively charged CHSB-AgNPs were more toxic to PSII of model plants than negatively charged TCSB-AgNPs and TA-AgNPs. AgNPs impact differed in the case of monocots and dicots, but the size of the changes was not significant, so it concerned individual parameters. The results revealed the interaction strength, which was generally similar in all tested plants, i.e., increasing negative effect in sequence TCSB-AgNPs < TA-AgNPs < silver ions delivered in the form of AgNO3 < CHSB-AgNPs.

The aim of this study was to assess the changes in chemical and microbial properties and enzymatic activity of soil enriched with vermicompost derived from household waste. The vermicompost was tested in the rhizosphere of Larix decidua seedlings cultivated in 10-L pots in: (i) nursery soil (as the control), (ii) soil with 10% v/v vermicompost, and (iii) with 20% v/v vermicompost. The impact of vermicompost was assessed in terms of soil C/N ratio; bacterial, fungal, and nematode counts; and enzymatic activity. It was found that vermicompost increased the C/N ratio from 21 to 32, as well as the content of nitrate from 78 to 134 mg kg−1, of ammonium from 14 to 139 mg kg−1, of phosphorus from 92 to 521 mg kg−1, and of potassium from 142 to 1912 mg kg−1, compared with the control soil. The abundance of beneficial bacteria was increased (from 8.61 × 107 to 37.9 × 107), along with decreases in microbiological ratios of fungi and bacteria (e.g. fungi/Bacillus from 0.18818 to 0.00425). A significant 2- to 4-fold increase was observed compared with the control in the number of beneficial nematodes belonging to bacterivorous, fungivorous, and predatory groups with no change in the abundance of plant-parasitic nematodes. Addition of vermicompost brought about a change in soil enzyme activity. Vermicompost reduced the activity of alkaline phosphatase only. Both doses of vermicompost led to an increase in the activity of acid phosphatase, inorganic pyrophosphatase, dehydrogenases, β-glucosidase, and urease. Only the higher dose had an effect on increasing the activity of o-diphenol oxidase and proteases. No significant change was observed for nitrate reductase. Also, the presence of antibiotics produced by bacteria was detected depending on the dose of vermicompost, e.g. iturin (ituC) and bacillomycin (bmyB) were found in soil with a dose of 20% v/v vermicompost. Overall, vermicompost produced from household waste can be an excellent organic fertilizer for larch forest nurseries.

Environmental Biotechnology deals with preservation and restoration of fauna, flora, and their environment. The utilisation of environmental biotechnology has significantly affected the world and will be one of the most valuable tools for improving the quality of life for future generations b y providing cost effective mechanisms for preserving and restoring natural resources. Biotechnology will also revolutionise many industrial processes by providing the ability to produce energy and chemicals through green processes that will minimise the impact of industrial activities on the environment and reduce the world's dependence on non-renewable energy resources. It will also enable the use of biological systems for the remediation of contaminated water and soils that result from many anthropogenic activities. The journal is devoted to biotechnological processes that preserve, protect and restore nature, mainly: • cytogenetic and molecular diagnostics of living andancient organisms,

BACKGROUND: Appropriate combinations of lactic acid bacteria (LAB) strains should be selected to optimize the ensiling process, and the additives should be adjusted to the ensiled forage crops. The aim of this study was to determine the effect of inoculation with three Lactobacillus species on the chemical parameters and microbiological quality (beneficial and harmful microbiota) of grass silage. RESULTS: Three species: L. paracasei (LPa), L. brevis (LB) and L. plantarum (LPl), isolated from sugar beet silage and characterized based on 16S rDNA sequences and biochemical parameters, were analyzed in the study. Single strains and their combinations were used as silage inoculants. The basic chemical and microbiological (qPCR) parameters of silages were determined. Based on the results of agglomerative hierarchical clustering (AHC) and principal component analysis (PCA) it was determined that silages inoculated with single LAB strains and LPa + LB and commercial additive (0+) were the best quality ones, particularly with regard to microbiological parameters and they effectively lowered the pH value. A consortium of three Lactobacillus species had no influence on silage quality, whereas LPa + LB and LPl + LB combinations as well as a commercial additive exerted positive effects. Inoculation inhibited the growth of toxin-producing fungi.CONCLUSION: Only the appropriate LAB composition can improve the quality of the ensiled material (antagonistic relationship). Only the LPa + LB combination was able to improve the value of low dry silage; nevertheless, almost all combinations were able to reduced concentrations of toxin-producing fungi. DISCUSSIONIn this experiment, grass herbage was obtained from the fourth cut due to higher expected fungal loads (in particular Fusarium spp.). A short regrowth period resulted in high crude protein content.

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Silver and titanium dioxide nanoparticles (AgNPs and TiO2NPs) are highly useful, but they are also a significant reason for concern as they exert toxicity. The goal of research was to assess the role of three kinds of NPs in concentrations of 100 mg L−1 on early growth plants (wheat, flax) and bacterial community in rhizoplane. Titanium (IV) oxide anatase (TiO2NPs1) and titanium (IV) oxide nanopowder (TiO2NPs2) are commercial products. A suspension of AgNPs was prepared via a procedure of reduction with tannic acid. The response of Monocot and Dicot growth form plants to the tested NPs was different. Germination and seedling growth of wheat treated with TiO2NPs1 was better. The response of flax to NPs was noted as an increase of chlorophyll content. The bacterial community in wheat rhizoplane was not significantly modified, but there was a declining trend. In turn, a difference in the surface charge of NPs had an influence on the total bacterial community in Dicot rhizoplane. Positively charged TiO2NPs2 significantly decreased the quantity of total bacteria in contrast to negatively charged AgNPs and TiO2NPs1 which increased it. A qualitative analysis did not confirm the influence of the surface charge of NPs on an increase/decrease in the quantity of Pseudomonas and Bacillus bacteria, but did show that there was no toxicity of the tested NPs to the plant growth-promoting bacteria community. The rhizoplane microbiome was dependent on the species of plant, and the bacteria found in the communities are sensitive to NPs to a varying degree.

Non‐systemic endophytes coexist with grasses and produce positive or negative effects for the host. In agricultural grasses, endophytes such as Epichloë spp. (formerly: Neotyphodium spp.) enhance the biometric parameters and agricultural value of grass biomass and seeds. Some endophytic fungi produce active substances that exert a negative influence on grass‐fed livestock. There is a general scarcity of studies investigating other endophytic fungi, the species composition of fungal communities, fungal species capable of colonizing different grasses and endophyte transfer between grass taxa. This study aims to fill in the existing knowledge gap by describing the relationships between fungal species and grass species. Timothy grass (Phleum pratense L.) is more readily colonized by endophytic fungi than perennial ryegrass (Lolium perenne L.), and the ratio of fungi isolated from the above species was determined at 3:1. Ecological indicators, especially diversity, were also higher in the fungal community colonizing timothy grass. The vast majority of the isolated fungi were ascomycetes. In addition, two Basidiomycota isolates and three Oomycota isolates (Phythium acanthicum) were also obtained from timothy grass. The most prevalent fungal species were Alternaria alternata, Microdochium bolleyi and Epicoccum nigrum. An analysis of minisatellite DNA regions revealed high levels of genetic polymorphism in A. alternata, whereas the remaining isolates were characterized by low levels of genetic variation or genetic homogeneity. The transfer of endophytic fungi between grass species was determined, which was one of the most important observations made in the study. The Sørensen–Dice coefficient reached 50%, which indicates that all fungal species isolated from perennial ryegrass are capable of colonizing timothy grass.