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The SP-A9 strain of Bacillus sp., which is most closely related to Bacillus subtilis, demonstrated excellent antifungal properties in laboratory analyses. The percentage of inhibition in the dual culture test was similar for all investigated phytopathogens (Fusarium culmorum, F. oxysporum and Monographella nivalis) at approximately 46%. The analyzed strain was found to be cellulolytic and strongly chitinolytic, and its biochemical properties indicate that it easily adapted to various environmental conditions. The strain's sporulation ability and high proliferation rate in acidic, alkaline, and highly saline environments (9% NaCl) further confirmed its adaptability to adverse conditions. In a pot experiment, the basic biometric parameters of spring wheat grain inoculated with Bacillus sp. SP-A9 were not modified, but a significant increase in grain yield was observed (by 18% in soil contaminated with F. culmorum and by 19% in soil contaminated with F. oxysporum). The increase in yield was correlated with the number of wheat plants, which suggests that the analyzed strain minimized the pathogen-induced inhibition of plant growth. Bacillus sp. SP-A9 can reduce economic losses resulting from diseases caused by fungi of the genus Fusarium and contribute to reduced use of crop protection chemicals, thus minimizing environmental pollution. [ABSTRACT FROM AUTHOR]

Studies on determination of the effect of herbicides on survivability of Plant Growth Promoting Bacteria have a strategic usefulness in determination of plant health and the fate of applied agrochemicals in agroecosystem. Antimicrobial potential was assessed using estimation of a minimum inhibitory concentration of the Roundup 360 SL against Pseudomonas sp. A quantitative analysis of bacteria was performed, and the tendency of physicochemical changes in the mineral medium was evaluated during long-term exposure to the herbicide. Furthermore, the antagonism of the SP0113 strain against F. culmorum and F. oxysporum under stress conditions caused by Roundup® 360 SL was verified. It was demonstrated that use of the undiluted and 2.6-fold diluted product resulted in the inhibition of growth of the investigated strain. Pseudomonas sp. SP0113 showed survivability and resistance to near recommended dose concentration of Roundup® 360 SL. The possibility of bacterial development on the Tryptic Soy Agar (TSA) medium at contact concentrations of 14.4 and 5.4 mg mL-1, as per the diluents quantity declared by the producer, indicates the role of cofactors such as: adiuvant or pH, redox potential (mV) or salinity. They comprise pH change, oxidation and salinity that may be due to the reaction of the active substance of the herbicide with mineral nutrient ingredients. The high salinity of environment, as a result of the reactions with the ingredients contained in the medium, is characteristic for concentrations higher than those recommended in practice. Furthermore, it was found that glyphosate limits the growth of fungi of the Fusarium genus, which support plant protection using strain SP0113. [ABSTRACT FROM AUTHOR]

The pathogenic fungus Heterobasidion annosum was identified in the rhizome of a couch grass ( Elymus repens) using genetic markers. The couch grass grew in the proximity of a Scots pine stand that was visibly affected by the pathogen. The rDNA analysis showed 100% sequence similarity between two H. annosum sequences of ITS1 and ITS2 obtained from fruiting bodies found on the couch grass rhizome and on the stem of the Scots pine. These results indicate a close relationship between the two isolates of H. annosum and that they are derived from a common ancestor. The results show that H. annosum mycelia can infect couch grass rhizomes and subsequently produce fruiting bodies. It also suggests that the known modes of infection of tree roots by this pathogen in coniferous stands should take into account couch grass rhizomes in the dispersal of the disease in afforested post-agricultural soils. [ABSTRACT FROM AUTHOR]

This study investigated the effects of various titanium nanoparticles (TiO 2 NPs) on the structure, function, and trophic levels of the wheat rhizobiome. In contrast to the typically toxic effects of small nanoparticles (~10 nm), this research focused on molecular TiO 2 and larger nanoparticles, as follows: medium-sized (68 nm, NPs1) and large (>100 nm, NPs2). The results demonstrated significant yet diverse impacts of different TiO 2 forms on the rhizosphere microbiota. Large TiO 2 NPs2 and molecular TiO 2 adversely affected the bacteriobiome and mycobiome, leading to an increase in autotrophic microbial groups. In contrast, medium-sized TiO 2 NPs1 shifted the microbiome toward chemoheterotrophy, promoting plant growth-associated bacteria, fungal saprotrophs, and potential phytopathogens, suggesting a beneficial r-strategy within the rhizosphere. Other treatments induced oligotrophic conditions, resulting in a less flexible rhizobiome with diminished root associations but an increased abundance of Trichoderma spp. Structural modelling revealed that even minor changes in operational taxonomic units (OTUs) could significantly alter the microbiota's metabolic potential. These findings highlight the importance of further research to optimize nanoparticle applications for sustainable agriculture.

The study was carried out to assess the effect of the larch wooly adelgid Adelges laricis Vallot (Hemiptera: Adelgidae) infestation on its secondary host, the European larch Larix decidua Mill. Morphology and anatomy of adelgid-infested needles, and content of defense phenolic compounds including individual flavonoids isorhamnetin, kaempferol, quercetin, rutin, catechin, epicatechin, apigenin, ampelopsin and taxifolin, were analyzed. The amount of total phenols in needles from adelgid-infested twigs of L. decidua increased following the development of the A. laricis population, from the end of April until the end of June. The most abundant among flavonoids were the flavanols, mainly catechin and epicatechin, which predominated in the larch needles during the whole period of adelgid infestation. The content of catechin and epicatechin increased following the increase in the adelgid population number. An increase in content occurred also in flavanonols ampelopsin and taxifolin, while the content of the flavonol kaempferol decreased as the population number of A. laricis increased. The analysis of the anatomical structure of needles showed changes in the shape of the needles, the presence of a thicker layer of epicuticular waxes, and a higher number of mesophyll layers as a result of adelgid feeding.

Three varieties of rapeseed (Castilla, California, and Nelson F1) were cultivated using medium-intensive (control), intensive, and economical (spare) technologies with different nitrogen and sulfur fertilization techniques. The antioxidant potential of rapeseeds was investigated using ABTS, FRAP, and DPPH assays. The content of total phenolic compounds was determined using the Folin-Ciocalteu phenol reagent. The profile of phenolic compounds was determined using high-performance liquid chromatography (HPLC). Diversifying fertilization in various ways influenced the content of phenolic compounds in extracts of rapeseed. In extracts from the Nelson F1 rapeseeds, intensive cultivation resulted in a lower content of phenolic compounds compared to the control group. Economic fertilization reduced the content of phenolic compounds in seeds from the California variety. HPLC chromatograms of the extracts were characterized by the presence of five (California and Castilla) and six (Nelson F1) main phenolic compounds. Two compounds were identified as sinapine and sinapic acid; others were classified as derivatives of sinapic acid. The effect of fertilization on the antioxidant activity of the seeds and their extracts varied depending on the plant variety and antioxidant assay. For the Castilla and California varieties, no differences were found in the results of the ABTS assay. The antiradical activity against ABTS •+ of extracts from the Nelson F1 intensive and spare cultivated seeds was higher than that of extracts from control seeds. The FRAP values of extracts/seeds from the Castilla variety cultivated using different methods did not differ significantly. The results of the DPPH assay were not affected by fertilization in the case of extracts from the California and Castilla varieties. However, the extracts from spare cultivated seeds of Nelson F1 exhibited stronger antiradical activity against DPPH • . These findings highlight the complex relationship between fertilization practices, phenolic compound accumulation, and antioxidant activity in rapeseed. Integrating varietal traits and cultivation practices is crucial for optimizing the nutritional benefits of rapeseed., Competing Interests: The authors declare no conflicts of interest.

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 × 10 7 to 37.9 × 10 7 ), 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.

Observations on population density of plant parasitic nematodes occurring in rhizosphere of broad bean cultivated in the crop rotation and long-term monoculture were performed during 2013-2014. 13 species were observed: Trichodorus primitivus, T. viruliferus, Paratrichodorus pachydermus, Criconema annuliferum, Paratylenchus projectus, Bitylenchus dubius, Merlinius brevidens, Pratylenchus fallax, P. flakkensis, P. neglectus, Heterodera triffolii, H. goettingiana, and Ditylenchus dipsaci. In monoculture plots 70-80% of eggs inside Heterodera cysts were colonized by pathogenic fungi (v.s. 50-62% of cysts from crop rotation). 12-18% of specimens of Pratylenchus species were colonized by the nematode-pathogenic bacteria: Bacillus penetrans.