Plant tissue culture is an important tool for accelerated vegetative reproduction of woody plants. To increase the efficiency of this method, it is necessary to search for new growth stimulators and protectors of microshoots. Two-dimensional (2D) nanomaterials are highly promising for applications in medicine and biotechnologies. We have studied the effects of TiS₃ nanoribbons with the following mean dimensions: thickness less than 100 nm, length 1–10 μm and width 0.4–1 μm upon poplar × aspen hybrid and downy birch microclones in plant tissue culture. We have found the effectiveness of this particular nanomaterial as a sterilizing and stimulating agent in the initial growth stage and as a rhizogenesis-activating agent in the rooting stage. We analyzed a wide range of TiS₃ concentrations in the nutrient media and identified 1.5 and 3 μg/L as optimal. However, concentration-dependent toxic effects manifesting themselves through microclones viability suppression have been discovered in the groups exposed to 6 and 15 μg/L TiS₃. We have established that plant reaction to TiS₃ treatment is specific for different plant species, i.e., downy birch is generally more tolerant than poplar × aspen hybrid. Here, we propose that the protective and stimulating effects of titanium trisulfide as well as its toxicity in high concentrations can be explained by the release of hydrogen sulfide as a result of aqueous hydrolysis of nanoribbons and its effect on plants. Additional studies are required in order to assess all biological effects produced by TiS₃ nanoribbons at further stages of ontogenetic development and to identify the mechanisms of their action.

The study is the first to examine the combined use of blast-furnace sludge as a source of microelements and converter slag as a soil-deoxidizing agent in oat (Avena sativa L.) cultivation in sod-podzolic soils. It has been established that blast-furnace sludge is a highly dispersed waste, which contains about 50% iron, 7% zinc, and a small amount of calcium, silicon, magnesium, aluminum, and sulfur. Hazardous components such as lead, arsenic, etc., are not detected. Converter slag comprises porous granules up to 3 mm in size, consisting mainly of calcium compounds (CaO, Ca(CO)₃, CaSiO₃, CaFe₂O₄) and a small amount of Mn, Al, and Mg trace elements. In a laboratory experiment, blast-furnace sludge increased the germination of oats by 5–10%, regardless of the addition of a deoxidizer (slag), but at the same time suppressed the growth of stem length by a maximum of 18% at 1 g∙kg⁻¹. The addition of slag raised substrate pH and increased the index by 8% at a sludge concentration of 0.1 g∙kg⁻¹. Root length in deoxidizer-free variants increased by 50–60% and with the addition of slag by 27–47%. Root dry mass also increased under the addition of sludge by 85–98%; however, the addition of slag reduced the indicator to the control level. In a field experiment with the combined application of waste, an increase in yield by more than 30% was shown. When soil was treated with slag and sludge, the height of plants increased by an average of 18%. It should be noted that the introduction of waste did not affect the quality of the grain. The use of slag increased the lead content in the soil, which is probably due to the sorption properties of calcium compounds in the slag, since lead was not found in the analyzed waste. Presumably, lead is sorbed by slag from the lower soil horizons, concentrating and immobilizing it in the upper layer. This version is supported by the absence of lead accumulation in straw and oat grain. The zinc-containing sludge increased the content of this element by 33% in the soil, as well as by 6% in straw and by 14% in grain. Thus, we found that the studied metallurgical wastes can be used as nutrients for agriculture, both individually and jointly. Overall, the proposed approach will contribute both to reducing the amount of accumulated waste and to improving the efficiency and sustainability of agricultural production and CO₂ sequestration. However, the features of the accumulation of heavy metals in soil and plants under the influence of the analyzed types of waste require more in-depth study, including within the framework of long-term field experiments.

Copper (II) oxide nanoparticles (CuO NPs) attract much attention as a promising antimicrobial agent. We studied the antibacterial properties of three types of CuO NPs against Escherichia coli bacteria: flake-shaped particles with a diameter of 50–200 nm and a thickness of 10–20 nm (CuO-CD synthesized by chemical deposition), spherical particles with a size of 20–90 nm (CuO-EE obtained by electrical explosion), and rod-shaped particles with a length of 100–200 nm and a diameter of 30 × 70 nm (CuO-CS commercial sample). We tested how the shape, size, and concentration of the NPs, and composition of the dispersion medium affected the properties of the CuO NPs. We prepared dispersions based on distilled water, a 0.9% NaCl solution, and the LB broth by Lennox and used Triton X-100 and sodium dodecyl sulfate (SDS) as stabilizers. The concentration of NPs was 1–100 mg L⁻¹. We showed that the dispersion medium composition and stabilizer type had the greatest influence on the antibacterial effects of CuO NPs. We observed the maximum antibacterial effect for all CuO NP types dispersed in water without a stabilizer, as well as in LB broth with the SDS stabilizer. The maximum inhibition of culture growth was observed under the influence of CuO-EE (by 30%) and in the LB broth with the SDS stabilizer (by 1.3–1.8 times depending on the type of particles). In the saline solution, the antibacterial effects were minimal; in some cases, the CuO NPs even promoted bacterial culture growth. SDS increased the antibacterial effects of NPs in broth and saline but decreased them in water. Finally, among the particle types, CuO-CS turned out to be the most bactericidal, which is probably due to their rod-shaped morphology and small diameter. At the same time, the concentration and aggregation effects of CuO NPs in the colloidal systems we studied did not have a linear action on their antibacterial properties. These results can be used in the development of antibacterial coatings and preparations based on CuO NPs to achieve their maximum efficiency, taking into account the expected conditions of their use.

The effect of copper(II) oxide nanoparticles (CuO NPs) of various morphologies at concentrations of 10–200 mg L^–1 on the microshoots of the hybrid white poplar × aspen and downy birch was studied. Low NP concentrations increased sterility and stimulated growth, whereas high concentrations inhibited development. Nanospheres and nanoflakes reduced contamination more effectively than nanorods. For the white poplar × aspen hybrid, the use of nanoflakes at a concentration of 10 mg L^–1 was optimal for sterilization and stimulation of multiplication, while for birch, nanospheres at concentrations of 10–100 mg L^–1 were optimal for reducing contamination. White poplar × aspen exhibited higher resistance to the effects of CuO NPs, whereas birch was more sensitive to NP exposure. Overall, CuO NPs appear to be promising agents for micropropagation; however, further studies are required to minimize phytotoxic effects.

Blast furnace sludge is a micro- and nano-dispersed metallurgical waste rich in iron and zinc, yet its accumulation poses a serious environmental challenge. Here we demonstrate its potential as a source of iron and zinc for sugar beet (Beta vulgaris L.), a crop with high micronutrient demand and economic importance. At application rates of 0.5–2 t ha⁻¹ in alluvial-meadow soils with neutral pH, the sludge increased root yield by up to 1.5-fold and sugar content by up to 1.4-fold compared to untreated controls. The optimal dose (0.1 g kg⁻¹ in greenhouse) significantly reduced the activity of oxidative stress markers—polyphenol oxidase (PPO) by 7.5-fold and peroxidase (POD) by 8-fold—indicating alleviation of cellular stress. The sludge also exhibited phytoprotective properties, reducing leaf necrosis under field conditions. A single application at these rates posed no food safety risks: lead and cadmium levels in beetroots and soil remained below international regulatory limits, and zinc accumulation in beetroots (≤10 mg kg⁻¹) was an order of magnitude below the FAO/WHO guideline. However, repeated annual applications would gradually increase soil zinc; preliminary screening suggests that applying 2 t ha⁻¹ annually could approach the soil MPC within 4–5 years under a linear accumulation scenario, necessitating long-term monitoring.

Due to the increasing use of nanomaterials in agriculture, the effects of copper(II) oxide nanoparticles (CuO NPs) on plants are of considerable interest. This study analyzes the effect of CuO NPs synthesized by chemical precipitation and electrical explosion of a wire, as well as a commercial CuO NP sample, all stabilized with the antimicrobial polymer polyhexamethylene biguanide hydrochloride (PHMB), on spring wheat (Triticum aestivum L.) seedlings. X-ray diffraction analysis and scanning electron microscopy have revealed significant differences among the samples in phase purity, particle size, and morphology (rod-shaped, spherical, and flake-like particles). Rod-shaped nanoparticles from the commercial sample exhibited the highest colloidal stability in aqueous dispersions. Bioassays have shown that all CuO NP dispersions enhanced seed germination and biomass accumulation, particularly in roots, while seedling length was reduced. The strongest stimulatory effect, including increased chlorophyll content and catalase activity, has been recorded for the commercial CuO NP sample at a concentration of 100 mg/kg. Copper accumulated predominantly in the above-ground parts of the plants. Overall, the results indicate that nanostructured CuO–PHMB complexes may represent an effective approach for improving the growth of spring wheat. However, long-term studies are needed to assess their ecological safety.