With the rapid progress of nanotechnology, nanoparticles and microparticles are extensively studied for their diverse applications, alongside growing concerns regarding their environmental impact and potential effects on living organisms. Nanoparticles, due to their size, can penetrate cell membranes, accumulate intracellularly, and influence molecular mechanisms, while microparticles tend to adhere to cell surfaces, affecting cellular transport pathways. This study investigates the short-term impact of four types of nano- and microparticles (SiO 2 (0.2–0.3 μm), Al 2 O 3 (2.5 μm), Ag (0.5–1 μm), and succinite (5 nm – 3 μm)), specifically those explored for developing novel biotextile materials with specialised protective capabilities against harsh environments. As a model we used Hordeum vulgare immature pollen cells (microspores). Microspores were incubated in vitro for 1.5 hours in media containing these particles. Relative cell autofluorescence was measured, and DNA changes were assessed using the inter-primer binding site (iPBS) fingerprinting method. Our results indicate that Al 2 O 3 and SiO 2 microparticles had a suppressing effect on microspore autofluorescence, whereas succinite (amber) particles had an increasing effect. Ag particles showed no significant effect on microspore fluorescence under the studied conditions. Crucially, the iPBS method revealed visible changes in the amplified barley microspore DNA spectrum in samples exposed to SiO 2 , Al 2 O 3 , or succinite nano- and microparticles, suggesting potential genotoxic effects. These findings underscore the importance of evaluating the diverse physiological and genetic responses of plant reproductive cells to various types of engineered nanoparticles and microparticles.

Molecular markers have become indispensable tools in contemporary ecological research, off ering insights into genetic diversity and structure. These parameters are pivotal for addressing fundamental questions in landscape ecology and planning eff ective species conservation. Grasshoppers have one of the largest genomes known. A signifi cant portion of the grasshopper genome is composed of mobile genetic elements, with a particular abundance of retrotransposons. In this study, we utilised the iPBS (inter-primer binding sequence) PCR based fi ngerprinting marker system, as a novel approach based on retrotransposons for the study of Orthoptera. We evaluate the efficacy of the iPBS primers system in characterizing the genetic diversity of two large-genome grasshopper species, Stethophyma grossum and Chrysochraon dispar. Our fi ndings demonstrate the potential of iPBS markers as a valuable tool for assessing the genetic diversity of orthopterans. This approach offers a promising avenue for future research in population genetics and conservation biology.

Abstract Silica or silicon dioxide nanoparticles (SiNPs) are one of the most widely spread nanoparticles in the environment, particularly, in urban areas in the form of dust. Influence of SiNPs on plant cells is unclear. This research was conducted to test a hypothesis that plant cell relative fluorescence and SiNP toxicity differ depending on the genetic properties and environmental conditions. Young pollen cells of lime trees in the mid to late one-nucleate developmental stage were found to be more sensitive to detect the influence of SiNPs and UV irradiation. Alteration of cell relative fluorescence depending on tree growth conditions was observed. Cells from trees grown in the urban area of Rīga had much lower reaction to SiNPs in comparison with cells from trees grown in the greenhouse. Lime trees growing for a long time in urban areas have complex adaptive features to a variable environment and can used as source-material to propagate lime trees for growing in such conditions. Flow cytometry can be applied for evaluation of plant reaction to factors that affect plants in the urban environment.

The impact of extremely low frequency electromagnetic field (ELF-EMF) on living organisms and the identification of their threshold levels remain uncertain. Amber nanoparticles and microparticles are being explored as potential raw materials used for production of innovative biotextiles. This study aimed to develop methods for assessing the protective properties of biotextiles against LF-EMF including testing the influence of a novel biotextile with incorporated amber particles on growth parameters of model bacteria and fungi species. The assessment of biotextile properties is based on comparison of mycelial growth in Petri dishes of fungi Chaetomium globosum Kunze: Fries (ATCC® 6205TM), and the growth rates of bacteria Enterococcus faecalis (Andrewes and Horder 1906) Schleifer and Kilpper-Bälz 1984 (NCTC 12697) and Escherichia coli (Migula 1895) Castellani and Chalmers 1919 (AL) (NCTC 12241), grown in flasks wrapped and unwrapped in fabrics with incorporated amber particles under LF-EMF exposure. While no significant differences were observed in the growth rate of E. faecalis under LF-EMF exposure, regardless of fabric wrapping, the biotextile with amber particles demonstrated a statistically significant protective effect (P < 0.01) inducing growth rate changes in E. coli.

Current technologies have become a source of electromagnetic pollution resulting from artificially generated electromagnetic radiation (EMR). To understand the influence of the EMR on living organisms, we investigated the long-term effects of EMR of 50 Hz frequency on duckweed (Lemna minor) clones. Experimental groups of duckweed were treated directly and indirectly by changing EMR generating magnetic flux (MF) starting from 2 µT (0–11 weeks from the beginning of the experiment) and switching to 300 µT (12–48 weeks) MF density during the second part of the experiment. The growth parameters (plant growth, frond area, and frond number) and the point mutations appearing at the antioxidant genes DNA sequences [ascorbate peroxidase (APx), glutathione peroxidase (GPx), and catalase (Cat)] were analyzed. The significantly enhanced number of nucleotide substitutions in DNA sequences of L. minor clones directly affected by LF EMR in comparison to indirectly affected clones was revealed at the introns of APx, GPx, and Cat genes starting from the 10th week of the experiment. The results indicate that even low-dose chronic electromagnetic radiation may contribute to the changes in growth parameters and generation of point mutations in antioxidant gene sequences, especially in the intron regions.

Abstract An established biotesting system designed to discover specific features of innovative multifunctional biotextile, encompassing integrated silica dioxide and succinite (Baltic amber) particles, is founded on reproducible, reliable, and relatively fast methods. The main idea starting this study was to create a system of test methods devoted to identification of specific features of biotextile materials designed to preserve living organisms from adverse environmental factors like enhanced electromagnetic radiation of different frequencies, without use of vivarium animals. Cultures of the freshwater macrophyte duckweed (Lemna minor) line Sta2 and fruit flies (Drosophila melanogaster) were chosen as model systems suitable for the study of the influence of electromagnetic field (EMF) radiation. The experiments showed changes of phenotypic features and growth parameters of test objects, as well as induction of point mutations of DNA (for example, insertions or deletions in chloroplast DNA and nucleotide substitutions in nuclear genes). The responses of test organisms induced by EMF were studied using microscopy, flow cytometry, and DNA sequencing methods. On the cell level, a new fast flow cytometry method for biotextile testing was developed: immature gametic (pollen) cell cultures were used as a highly sensitive model system (plant gametic cell response is comparable to human neutrophil response) to study the influence of EMF radiation. The method was based on the measurement of differences of fluorescence intensity between group of cells experimentally affected by EMF radiation and non-affected cells.

Amphibian populations are increasingly threatened by global change and the study of their genetic diversity is a major conservation priority. Western palearctic tree frog species of the Hyla arborea group are commonly distributed across Europe and the Middle East and many have declining populations. We performed a PRISMA systematic review to gain insight into the genetic diversity of H. arborea group. Sixteen published studies were included in the final qualitative analysis. While the genetic diversity of H. arborea group species was widely variable, it could often be explained by phylogeographic history. Populations in Western and Northern Europe had lower genetic diversity, with some populations also affected by habitat fragmentation. However, important regions of high genetic diversity were found in the Balkan peninsula for H. arborea sensu stricto and around the Black Sea for H. orientalis. Genetic diversity of H. molleri, H. savignyi, H. meridionalis, H. felixarabica, H. intermedia, H. sarda has been investigated only across extensive phylogeographical studies, while data regarding their genetic diversity at the local level are missing. Through our review, we identify knowledge gaps about the genetic diversity of the H. arborea group that require further investigation, of and illustrate how filling these gaps might translate into future conservation efforts.

Development of new technologies distributing electric power from power stations to our homes through a network of cables and wires, including numerous electric devices at working places and home environment become a source of electromagnetic radiation (EMR) much stronger than EMR of natural origin. To provide a better understanding of the impact of the EMR of anthropogenic origin on living organisms, we investigated the long-term effects of EMR on Lemna minor. In this study, plants of the L. minor laboratory clone were exposed to low frequency (50 Hz) electromagnetic radiation (LF EMR) growing clones in Petri dishes placed on the coils initially generating magnetic flux (MF) of 1 µT for first three weeks, 2 µT until 12th week and after 12th week of the experiment MF was enhanced up to 300 µT. We exam-ined the response of the plants by sequencing DNA fragments that included promoter, intron, and exon regions of ascorbate peroxidase (APx), glutathione peroxidase (GPx), and catalase (Cat) genes) as well measured growth parameters growth intensity, frond area, and number of fronds. Comparison of growth parameters of L. minor clones exposed to 2 µT and 300 µT magnetic flux revealed positive effect stimulating growth of experimentally affected plants at 2 µT After the first 14 weeks of treatment, the growth parameters were lower in the directly exposed by LF EMR group than in the group grown distantly from the source of EMR. However, after 18 weeks from the beginning of the experiment no significant difference was observed between two groups of L. minor including directly and indirectly affected by LF EMR plants. Moreover, the signals of the impact of LF EMR on the plants as rising of new point mutations were detected. The significantly enhanced number of variations in DNA sequences of L. minor clones directly affected by LF EMR in comparison to indirectly affected clones were revealed at the introns of APx (P = 0.011), GPx (P = 0.009), and Cat (P = 0.044) genes starting from the 10th week of the experiment In conclusion, the comparison of DNA sequencing data together with measurements of growth parameters revealed differences in response at molecular and physiological levels of directly and indirectly affected L. minor clones providing evidence that response to the impact of LF EMR depended on the prolongation of the impact and the magnetic flux density.

Abstract Common duckweed (Lemna minor L.) is a widely used plant for phytoremediation and environment monitoring of wastewater in vivo, as this plant can be efficiently grown in Petri dishes and quickly multiplied in laboratory conditions. It is also a valuable test object to study the impact of various environmental factors by measuring growth and biochemical parameters. Our goal was to establish an axenic diploid line of L. minor free from symbionts, for use as a model plant to obtain reproducible results in experiments. In this work, we used 29 L. minor clones collected in natural conditions in Lithuania and Latvia, which were naturally inhabited with bacteria and algae. The L. minor clone entitled Sta2 was found to be best to fit requirements to establish a laboratory line suitable for testing of the genetic and physiological influence of environmental factors. Application of flow cytometry, confocal laser scanning microscopy, and sequencing of catalase, glutathione peroxidase, and ascorbate peroxidase genes proved that the selected and specifically sterilised line Sta2 was diploid and free from symbiotic bacteria or algae. Media for storage and for rapid propagation of L. minor biomass were also developed. The axenic line Sta2 can be maintained in sterile laboratory conditions and can be used as a model organism in a wide spectrum of biological and environmental investigations.

n the study we subjected for biological testing succinate (5–3000 nm), silica (200–300 nm), aluminium (2500 nm), and silver (500–1000 nm) particles potentially applicable in the production of novel 3D biotextile. The effects of selected particles were evaluated in drosophila model by measuring the parameters potentially to be affected during the development. At the concentrations tested (0.01% and 0.1%), no clear adverse effects on egg to imago viability and locomotor activity, size, and phenotype of enclosed flies were found.

Cloudberry (Rubus chamaemorus L.) is an economically important plant that is already cultivated. The aim of the study is to create and analyze a collection of cloudberry sam-ples representing Latvian population.

The intraspecific genetic diversity of freshwater fish inhabiting hydro-systems of the macrogeographic area spreading from the Black to Baltic Seas requires comprehensive investigation from fundamental and practical perspectives. The current study focused on the involvement of the mtDNA ATP6 region in the adaptability and microevolution of Perca fluviatilis within phylogeographic and anthropogenic contexts. We sequenced a 627 bp fragment encompassing the ATP6 region and used it for genetic analysis of 193 perch caught in Latvia, Lithuania, Belarus, and Ukraine, representing natural and anthropogenically impacted populations. We evaluated patterns of intraspecific genetic diversity in the ATP6 region and phylogeographic trends within the studied area compared with previously established D-loop trends. Evaluation of ATP6 coding sequence variability revealed that among 13 newly detected haplotypes, only two were caused by non-synonymous substitutions of amino acids of the protein. PCoA revealed three genetic groups (I-III) based on the ATP6 region that encompassed four previously described genetic groups established based on the mtDNA D-loop. The two mtDNA regions (D-loop and ATP6) have microevolved at least partially independently. Prolonged anthropogenic impacts may generate new point mutations at the ATP6 locus, but this phenomenon could be mainly concealed by natural selection and reparation processes.

Abstract Inter-primer binding site (iPBS) molecular retrotransposon-based markers are a universal and simple tool to estimate genetic diversity. The goal of this study was to select highly informative iPBS primers to be used in studies of intraspecific genetic diversity of cloudberry (Rubus chamaemorus L.), a common plant species of the boreal zone, associated with raised bog habitats and transitional bogs. Initially, 75 iPBS primers were screened and three of the most informative primers (indicated by numbers 2298, 2277, and 2229) were selected based on the highest number of polymorphic bands and PIC (polymorphic information content) values. Electrophoretic analysis revealed 34 bands amplified with primer 2229, 25 bands with primer 2298, and 22 bands with primer 2277. The percentage of polymorphic loci ranged from 90.9 to 97.1% and PIC values ranged from 0.4885 to 0.4965, indicating potential of the selected primers to be applied in population genetic studies of R. chamaemorus.

The white clover (Trifolium repens L.) has a wide distribution range of habitat – from the Arctic to the subtropics, as well as up to 6000 m high alpine regions. It is found in various areas – in the wild, in agricultural areas, and the urban environment. Retrotransposons are mobile genetic elements that can move through the genome using the “copy-paste” principle are activated when a plant is affected by a stressor. The ability to respond to environmental changes makes retrotransposons very successful functional markers for a stress study. A universal retrotransposon-based method iPBS (inter primer binding sites) which was developed by Kalendar et al. (2010) was used for the study of UV irradiation influence. It can be observed that after the treatment with UV-B radiation, the movement of retrotransposons is activated, which suggests that in this way protection against UV-B radiation is provided. It can be observed that the insertion of retrotransposons after irradiation with UV-B radiation within the same genotype takes place in the approximately same location in all the examined groups – after UV-B irradiation 15, 30, and 45 minutes.

In this research, we focused on testing the physical and mechanical properties of the developed polyacrylonitrile (PAN) composite nanofibers with succinite (Baltic amber) and SiO2 particles using standard methods of nanofiber testing (physical and mechanical properties). Polyacrylonitrile composite nanofibers (based on the electrospinning method) were coated on an aluminum substrate for structural investigation. SEM was used to determine the average fiber diameter and standard deviation. The mechanical properties of the fibers were determined using a universal testing machine (NANO, MTS). We observed that constant or decreased levels of crystallinity in the ultrafine composite nanofibers led to the preservation of high levels of strain at failure and that the strength of nanofibers increased substantially as their diameter reduced. Improvements in PAN composite nanofibers with succinite and SiO2 nanopowder are feasible with continuous decreases in diameter. The drastically decreased strain at failure demonstrated a substantial reduction in viscosity (toughness) of the annealed nanofibers. Large stresses at failure in the as-spun nanofibers were a result of their low crystallinity. As a result, decreasing the diameter of PAN nanofibers from approximately 2 micrometers to 139 nanometers (the smallest nanofiber tested) resulted in instantaneous increases in the elastic modulus from 1 to 26 GPa, true strength from 100 to 1750 MPa, and toughness from 20 to 604 MPa.

The testing of an innovative amber-containing biotextile developed within the EUREKA project IFSITEX revealed the ability of biotextile material to protect test objects from UV-B radiation and extremely low-frequency electromagnetic fields (ELF-EMFs). One of two different testing methods is based on flow cytometry indicating changes in the relative fluorescence of immature plant gametes based on the determination of the sum of changes in approximately 20 various parameters of gametic cells affected in one nuclear stage by irradiation of cell suspension covered with biotextile fabrics containing amber particles or similar fabrics lacking amber particles with UV-B for 75 minutes. The second test called Drosophila melanogaster survivability test, specifically modified for biotextile testing, revealed differences in the percentage of successful development of D. melanogaster from larvae to imago stage after growing fruit flies in tubes covered with biotextile material containing amber particles as well as material free of amber particles. Tubes with D. melanogaster larvae were placed in a Helmholtz coil were continuously exposed to a sinusoidal 50 Hz magnetic field (MF) at a flux of 450 μT. Survivability results were compared to the success of the development of the control which was not affected by experimentally generated ELF-EMFs D. melanogaster. Samples of biotextile containing amber particles were found to retain UV-B and LF-EMF radiation better than fabric samples without amber particles.

One of the criteria for bio-textiles is the potential for biodegradation. Our goal was to adapt methods for the determination of biodegradation of bio-textiles containing amber particles. We adapted methods EN ISO 11721-1: 2001 and ISO 11721-2: 2003 developed for the study of interaction of cellulose – containing textiles and microorganisms. To determine the changes of fabrics, the mechanical properties and level of biodegradation were examined. Experiments revealing level of biodegradation of bio-textile were carried out at the Institute of Biology, University of Latvia while mechanical properties were tested at the Scientific Laboratory of Mechanics and Bio-textiles of the Institute of Mechanics and Mechanical Engineering, Riga Technical University. The study was financially supported by the EUREKA project E!11170 “Innovative multifunctional bio-textile, integrated with silica dioxide and succinate development, and its impact on biosystems” (IFSITEX).

Abstract Sprouts of diploid red clover ‘Stendes Agrais’ were treated with 0.2% colchicine solution. The ploidy level of plants was detected by flow cytometry. Most of the treated plants were mixoploids and sterile. From progenies of fertile plants, mixoploids were selected that had a proportion of tetraploid cells higher than 60%. In the next generation, stable tetraploid plants were selected, and 49 lines were included in the breeding process.