Background: Protocorm-like bodies (PLBs) represent a major morphogenic pathway in orchids and are characterized by cellular reprogramming, tissue differentiation, and developmental reorganization. Although PLB formation is widely explored for orchid micropropagation, endopolyploidy dynamics during PLB morphogenesis remain poorly understood. Aims: This study aimed to characterize endopolyploidy patterns and evaluate nuclear DNA content maintenance during PLB morphogenesis and plant regeneration in Cattleya tigrina. Methods: Basal leaf explants were cultured under PLB-inducing conditions in vitro. Morphological and histological analyses were performed throughout PLB development, while nuclear DNA content was estimated by flow cytometry in leaf regions, PLBs at successive developmental stages, and regenerated plants. Results: The leaf base was the most responsive region for PLB induction, showing intense cell proliferation and meristematic activity. Flow cytometric profiles consistently revealed 2C, 4C, and 8C nuclear DNA peaks, indicating endopolyploidy in somatic tissues. PLBs exhibited transient shifts in ploidy distribution during active proliferation phases, particularly at intermediate developmental stages, when 4C nuclei became predominant. Regenerated plants maintained nuclear DNA contents comparable to the original explants. Conclusions: Endopolyploidy is an intrinsic and developmentally regulated feature of PLB morphogenesis in Cattleya tigrina. PLB-mediated regeneration maintained overall nuclear DNA content under the evaluated in vitro conditions.

Background: RAB Guanine Nucleotide Dissociation Inhibitors (RAB GDIs) are important vesicle transport regulators in eukaryotes, participating in the functional cycle of RAB GTPases by stabilizing their non-active GDP-conformation. Aims: We address the importance of the three Arabidopsis thaliana RAB GDI paralogs by genetic and developmental analyses and put these results into the seed plants evolution context. Methods: We use methods of genetics, microscopy, and phylogenetics. Results: Our genetic analyses of Arabidopsis T-DNA insertional mutants confirm recent CRISPR alleles data indicating lethality of double gdi1 gdi2 mutants, and our microscopic data point to embryo development arrest in double mutant seeds. We also confirm the involvement of GDI2 and GDI3 in pollen tube growth. Moreover, our data show that GDI1 also contributes to proper pollen function. Our phylogenetic analysis reveals independent diversification of RAB GDIs in Gymnosperms and Angiosperms, with early specialization of an Angiosperm reproduction- and gametophyte-related clade. Conclusions: In Arabidopsis, RAB GDI1 and 2 are important for the vegetative growth while RAB GDI2 and 3 are vital for reproduction. Evolution of the RAB GDI family reflects the evolution of seed plants.

Background: The tomato brown rugose fruit virus (Tobamovirus fructirugosum, ToBRFV) is an emerging tobamovirus that has quickly become a significant obstacle to the production of tomatoes and peppers worldwide. It is now classified as a regulated quarantine pathogen. Effective containment requires rapid, reliable, inexpensive, and safe diagnostic protocols for routine screening in laboratories and production systems.
Aims: We aimed to thoroughly evaluate integrated molecular and serological diagnostic methods for ToBRFV and develop biosafe positive controls suitable for high-throughput and decentralized applications.
Methods: We evaluated the following methods: conventional RT-PCR, one-enzyme RTX-PCR, immunocapture RT-PCR, recombinase polymerase amplification, loop-mediated isothermal amplification with colorimetric detection, Western blotting, dot blot, and tissue blot immunoassay. The non-infectious positive control was prepared using the GoldenBraid 3.0 cloning system. We developed a single-seed assay that enables direct testing of tomato seed stocks.
Results: Among the evaluated molecular methods, RTX-PCR was particularly advantageous due to its minimal sample handling, reduced cost, and ability to bypass RNA extraction. The tissue blot immunoassay enabled high-throughput, low-cost screening of hundreds of samples per day using only basic equipment. Although ToBRFV was frequently detected in seeds harvested from infected plants, no systemic infection was observed in progeny seedlings, confirming the low rate of true vertical transmission. A non-infectious positive control was prepared and successfully employed in molecular methods.
Conclusions: Our findings provide an integrated diagnostic framework combining molecular, serological, and biosafety tools to effectively monitor and contain ToBRFV in commercial production and phytosanitary settings.

Background: The Viola plants have important value for theoretical and applied research. Agrobacterium-mediated transient expression enables rapid target protein production in plants, yet this system remains poorly established in Viola. Aims: To establish an efficient Agrobacterium-mediated transient expression system in Viola. Methods: By employing two types of A. tumefaciens strains (EHA105 and LBA4404) and green fluorescent protein (GFP) as a reporter, we demonstrated the transient expression in the leaves of four Viola species, including Viola philippica, V. prionantha, V. tricolor, and V. dissecta. Results: GFP transient expression peaked at 4 dpi in all four Viola species. Agrobacterium at OD₆₀₀ = 0.3 yielded optimal expression, and strain EHA105 was superior to LBA4404; V. philippica showed the highest GFP accumulation. In the optimal system, exogenous indole-3-acetic acid (IAA) improves GFP transient expression with maximum promotion at 50 ng/mL, while methyl jasmonate (MeJA) has no facilitating effect. This system enables transient expression of FMDV VP1, whose expression is also markedly increased by 50 ng/mL IAA. Conclusions: This study successfully established a transient expression system for Viola and identified factors affecting Agrobacterium-mediated transient expression efficiency in this genus.

Background: Stem base rot disease poses a serious threat to the Cyclocodon lancifolius industry, yet its causal agent remains unidentified. Aims: In this study, we aimed to identify the pathogenic fungi responsible for this disease and to screen for effective biocontrol strains against the causal agent. Methods: We isolated and identified the fungal pathogen from the stem base of diseased plants and confirmed its pathogenicity by fulfilling Koch's postulates. Multilocus sequence analysis identified the pathogen as Stemphylium lycopersici. Results: An antagonistic strain, Bacillus subtilis YHYS1, exhibited significant inhibition (51.8%) of S. lycopersici growth in a plate confrontation assay. Volatile compound analysis further confirmed the fungistatic potential of YHYS1. These findings highlight the promise of YHYS1 as an eco-friendly alternative to chemical fungicides for controlling stem base rot disease in C. lancifolius caused by S. lycopersici. Conclusions: Our characterization of this novel disease in C. lancifolius has elucidated the pathogenic features of Stemphylium species, an essential yet understudied group of plant pathogens. These findings provide valuable references for the diagnosis and control of diseases affecting C. lancifolius.

Background: Cymbidium faberi Rolfe is an ornamental orchid of high economic value, however, an efficient genetic transformation system has not yet been reported for this species. Aims: This study aimed to establish an Agrobacterium tumefaciens-mediated genetic transformation system for C. faberi and to optimize the key factors affecting transformation performance. Methods: Rhizomes, calli, and inflorescences were used as explants. The pCAMBIA3301-EGFP vector was introduced using Agrobacterium strain GV3101. Explant type, pre-culture duration, bacterial density (OD₆₀₀), infection time, co-cultivation period, and antibiotic selection were systematically optimized. Putative transformants were screened by green fluorescence and verified by polymerase chain reaction (PCR). Results: Calli pre-cultured for 3 d were the most suitable recipient material. The optimal transformation conditions were an Agrobacterium suspension of OD₆₀₀ = 0.2, infection for 5 min, and co-cultivation for 2 d; under these conditions, explant survival reached 72.22%. Two independent transgenic plantlets with stable integration of the enhanced green fluorescent protein gene were obtained and confirmed by PCR. Conclusions: This study provides an Agrobacterium-mediated transformation protocol for C. faberi and offers a technical basis for molecular breeding and gene function studies in this orchid.

Background: In the last decades, vacuum infiltration had been applied for the Agrobacterium-mediated transient expression of foreign gene in plants. However, the relevant influencing factors have not been fully studied yet. Aims: This study aimed to evaluate the effects of vacuum infiltration pressure, time of vacuum infiltration, concentration of Agrobacterium tumefaciens (A. tumefaciens), and incubation time post infiltration on the transient expression of foreign gene in leaves of Nicotiana benthamiana (N. benthamiana). Methods: Two A. tumefaciens strains, LBA4404 and EHA105, carrying a reporter gene of green fluorescent protein (GFP), were used to infiltrate leaves of N. benthamiana via vacuum infiltration. The changes of GFP expression with changes of vacuum infiltration pressure, time of vacuum infiltration, concentration of A. tumefaciens, and incubation time post infiltration were measured. Results: Increase of vacuum pressure from 0.03 to 0.07 MPa increased the GFP expression in the leaves infiltrated with either LBA4404 or EHA105, and the vacuum pressure at 0.07 MPa made almost all of area of the infiltrated leaf express GFP. The increase of the time of vacuum infiltration from 10 to 20 min significantly enhanced the GFP expression in either the LBA4404 or EHA105-infected leaves. Among the different concentrations of Agrobacterium (from OD600 0.1 to 0.9), the concentrations of LBA4404 strain suspension at OD600 0.5 and EHA105 strain suspension at OD600 0.3, respectively, were most effective concentrations for enhancing the GFP expression in the infected leaves. The increase of incubation time post infiltration from 2 to 4 days largely enhanced the intensity of GFP expression in the either LBA4404 or EHA105-infected leaves. However, further increase of incubation time post infiltration from 4 to 6 days decreased the GFP expression in the infected leaves. Conclusions: Vacuum infiltration pressure/time, concentration of A. tumefaciens, and the incubation time post infiltration were important factors affecting the level of transient expression by vacuum infiltration. Optimizing these factors is essential for improving the level of transient expression of foreign gene by vacuum infiltration.

Background and aims: Tire wear microplastics (TWMs) are emerging environmental contaminants, but their ecological risks to agricultural systems remain poorly understood. Methods: Rice seedlings were exposed to 0, 10, 100, and 1 000 mg L^-1 TWMs for 10 days. Growth parameters, chlorophyll fluorescence, and antioxidant enzyme activities were measured. Results: TWMs promoted growth; exposure to 1 000 mg L^-1 TWMs increased plant height and root length by 8.06% and 57.38%, respectively. Chlorophyll fluorescence analysis revealed that TWMs significantly suppressed rETR_max by 32.53 - 43.62% and altered qP and NPQ. TWMs inhibited Y(NPQ) while enhancing Y(NO) loss, indicating impaired photoprotective dissipation and aggravated photodamage. TWMs also inhibited SOD, POD, CAT, and APX activities in both leaves and roots, with root CAT and APX decreasing by up to 37.35% and 40.34%, reflecting a direct impairment of the antioxidant defense system. Conclusions: Rice seedlings achieve TWM-induced short-term growth at the expense of compromised photosynthetic efficiency and antioxidant defense, leading to an unsustainable compensatory state. This study provides physiological evidence for assessing TWMs phytotoxicity in agricultural systems.

Background: Idesia polycarpa var. vestita Diels is an oil-bearing woody plant of significant economic value. Aims: To accelerate the propagation of its elite germplasm, this study aimed to establish an efficient and stable in vitro rapid propagation system using one-year-old stem segments from elite plants. Methods: Young stem explants were disinfected with 75% ethanol for 40 s, followed by 0.1% HgCl₂ for 6 min. MS or 1/2 MS served as basal media, and various combinations of plant growth regulators were tested for axillary bud induction, proliferation, and rooting. Results: The optimal disinfection protocol yielded a 38.10% survival rate. The best axillary bud induction medium was MS + 1.5 mg/L 6-BA + 0.05 mg/L NAA + 0.08 mg/L TDZ, achieving 100% induction. For proliferation, MS + 1.5 mg/L 6-BA + 0.06 mg/L NAA + 0.01 mg/L TDZ (proliferation coefficient 5.81) was optimal. Rooting was best with 1/2 MS + 0.3 mg/L IAA + 0.1 mg/L NAA (100% rooting, 14 roots/plant). Conclusions: This study established a reliable micropropagation system for Idesia polycarpa var. vestita, providing technical support for the efficient production of high-quality seedlings.

Imported from Scholar: Original Article

Thioredoxins (Trx) are small multifunctional redox proteins that contain thioredoxin conserved domain and active site WCXXC. The Trx family has an important role in multiple processes, including electron transport, seed germination, redox regulation, biotic and abiotic stresses resistance, etc. Although Trx genes have been extensively characterized in some plants, they have not been reported in peanut until now. The identification of AhTrx genes provides potential candidate genes for studying their effects and regulatory mechanisms in peanut (Arachis hypogaea L.) growth and development, especially under aluminium (Al) stress. It is also helpful to further analyze the Al resistance pathway in plants. Seventy AhTrx genes were identified using a genome-wide search method and conservative domain analysis. Then the basic physicochemical properties, phylogenetic relationship, gene structure, chromosomal localization, and promoter prediction were studied by the bioinformatic methods. Furthermore, the expressions of AhTrx genes under different Al treatment times in two peanut cultivars were tested using a real-time quantitative polymerase chain reaction. Seventy AhTrx genes were identified and characterized. Phylogenetic tree analysis showed that all AhTrx members could be classified into 9 groups with different conserved domains. Motif 1 was found to exist in every sequence, with an active site. Furthermore, the gene structures showed that the AhTrx family was complicated and changeable during evolution. The chromosomal localization indicated that the distribution and density of the Trx family on 20 peanut chromosomes were uneven. Predictive promoter analysis indicated that AhTrx proteins might play a role in phytohormones synthesis and stress response. Finally, the expression patterns of the AhTrx genes showed that every gene was differently expressed under Al treatment in different peanut cultivars, some were obvious, others had no significant difference, some were at a high level, while others were at a low level. This study systematically identifies the Trx gene family in peanut, providing some candidates for further study on its effects and regulatory mechanism under Al stress in peanut.

In plant breeding, polyploidization is an established technique to obtain superior phenotypic characteristics. In seed propagated agricultural crops, seed treatments with antimitotic agents are often used to obtain chromosome doubling. Here, we developed a method to induce polyploidization in clonally propagated fodder grasses Lolium, Festuca, and the intergeneric hybrid Festulolium. The aim was to obtain specific genotypes at both the diploid and tetraploid levels. We evaluated different types of plant explants, and the effects of the type, concentration, and application mode of three antimitotic agents (oryzalin, colchicine, and trifluralin) on the survival rate and the polyploidization efficiency. The treatment of greenhouse-grown tillers with antimitotics only resulted in mixoploids, while tissue culture propagated plants were successfully polyploidized. A shock pretreatment, using a high concentration of an antimitotic agent during a short period, successfully induced tetraploids in all three genera. Additionally, supplementing the tissue culture medium with a lower dosage of an antimitotic agent during minimal four weeks after the shock pretreatment further promoted polyploidization. By our methods, we were able to generate diploid and tetraploid plants with an identical genomic constitution but different ploidy allowing investigation of the effects of polyploidization on plant physiology and gene regulatory networks.

Background and aims: There appears to be a strong correlation between the rapid proliferation of shrubs in the alpine grassland of the Qinghai-Tibet Plateau and the root exudates of these plants. The dynamics of root exudates during shrub development, however, have been the subject of few investigations. Methods: This work examined Lonicera thibetica, a plant found on the eastern edge of the Qinghai-Tibet Plateau. It focused on the root systems of 5-, 10-, 15-, and 20-year-old L. thibetica plants and how their primary organic acid components changed with the seasons and other circumstances. Results: The findings revealed that the primary components of acid secretion in the roots of L. thibetica were oxalic acid, lactic acid, and tartaric acid; of these, oxalic acid made up over 50% of the total organic acid content. The levels of these organic acids often dropped as shrubs got older, and their seasonal dynamics exhibited a parabolic shift pattern, typically peaking during the robust development stage. According to regression analysis, soil moisture was the primary determinant of the concentration of organic acids produced by alpine shrub roots, suggesting that soil moisture played a crucial role in the secretion process. Conclusions: The physiological dynamics of roots and the mechanisms that regulate them throughout the expansion of alpine shrubs can be better understood thanks to this work.

Background: Many concerns have been raised about the extensive use of agrochemicals and their impacts on environment and soil. Some serious issues include increased soil salinization, toxicity and decrease in soil microbial biodiversity. Biostimulants have emerged as a promising ecofriendly alternative to agrochemicals. Humic substances (HSs) are biostimulants with many beneficial effects in plants physiology and productivity. Aims: This review aims to synthesize current evidence on the role of HSs in supporting sustainable agriculture that improves crop productivity while maintaining good soil health in changing environmental conditions. Methods: Relevant studies related to HSs and their effects on soil fertility, plant growth, stress tolerance and hormonal regulation were collected from major scientific databases including Scopus, Web of Science, and Google Scholar. The main outcomes of these studies were extracted and analyzed to provide an overview of the available evidence. Results: The literature shows that the integration of HSs into agricultural practices improves soil structure, increases water retention, maintains healthy microbial diversity and enhances plant productivity. Conclusions: This review highlights the importance of using HSs in enhancing soil health and plant physiology. However, further studies are required to integrating new technologies and diversify HSs sources, plants species, and different environments.

Excess water is an abiotic stress in plants, but the level at which excess water becomes varies widely between plant species. We conducted a two growing season replicated excess flooding experiment that was planted with 24 accessions of perennial ryegrass which had been vegetatively propagated to ensure equal representation of genotypes within an accession, both cultivars and ecotypes, from various geographical origins. The excess water treatment applied over the winter periods was achieved with irrigation. Yields increased in the winter-flooded treatment in contrast to the non-artificial watered control treatment significantly in 2017. In 2018 the same trend could be seen, but was not significant. Differences in composition of macro- and micronutrient profiles were observed. Sulphur was the only element with highly significantly increased concentration (0.25%) in flooded samples compared to control. Phosphorus, copper, iron, manganese, and molybdenum decreased statistically significantly under flooded conditions. In conclusion, perennial ryegrass is coping extremely well with excess water supplied over the winter period and can utilise it effectively in spring.

Background: Platycladus orientalis L. is a drought-tolerant conifer valued for its ornamental and medicinal properties. However, efficient regeneration systems for this species remain limited, hindering its propagation and conservation. Aims: The aim of this study was to develop a reliable protocol for indirect organogenesis of Platycladus orientalis under in vitro conditions, evaluating the influence of explant type, culture medium, light exposure, and pretreatment on regeneration efficiency. Methods: Cotyledon, hypocotyl, and radicle explants were cultured on different media formulations. The effects of light and darkness during callus induction and shoot elongation were compared. Seeds underwent or avoided vernalization and scarification treatments to assess their influence on germination and callus formation. Results: Cotyledon explants achieved the highest callus induction rate, reaching 74.06%, particularly under dark conditions. Exposure to light during elongation significantly enhanced callus proliferation and shoots differentiation. Quoirin and LePoivre medium promoted the greatest number of adventitious shoots, with an average of 7.9 shoots per explant, while other media tested showed lower effectiveness. Germination was higher in non-vernalized and non-scarified seeds cultured in Quoirin and LePoivre medium. Conclusions: The established protocol enables efficient indirect organogenesis and shoot regeneration of Platycladus orientalis using cotyledon explants and Quoirin and LePoivre medium. The finding provides a valuable tool for clonal propagation and conservation of this species, supporting both ornamental cultivation and the preservation of its genetic resources.

In Arabidopsis, there are 14 TFIIB-like proteins that have been phylogenetically categorized into the TFIIB, BRF, and Rrn7/TAF1B/MEE12 subfamilies. The TFIIB transcription factor (TF) subfamily plays a key role in the regulation of gene expression in eukaryotes. To identify the expression patterns of some members of the TFIIB and BRF subfamilies in A. thaliana, different approaches were carried out to determine the possible functions of some of these transcription factors. Through an in silico analysis, we identified possible cis-acting regulatory elements in the promoter regions that drive the expression of transcription factors, as well as we evaluated their expression by means of real-time qPCR, at different growth stages and under various stress conditions. Cis-acting elements analysis showed that general transcription factors possess stress-responsive elements such as W-Box (TTGACC/T type binding WRKY TFs), ARF1 (auxin response), MYB binding site promoter (auxin response and elicitors), RAV1-A (response to dehydration and salinity), and DRE elements (dehydration response) among others. The experimental results showed differential expression of TFIIB1 and TFIIB. In addition, we demonstrate that in stress conditions a transcript of the TFIIB1 factor is generated as an alternative splicing product by retention of the third intron, where a premature termination codon is found. This is the first report of an alternative splicing event in a general transcription factor related to RNA pol II, which is synthesized when the plant is under abiotic stresses such as heat, dehydration, and salinity.

Interspecific and intergeneric hybridization within the Festuca-Lolium complex is frequently used in forage plant breeding. However, little is known about the natural occurrence and competitiveness of such hybrids. We collected naturally formed hybrids between Festuca apennina, Festuca pratensis, and Lolium perenne in different habitats of Switzerland and the British Isles and studied their origin, the ease of their spontaneous formation, and their competitiveness with parental species. A special attention was paid to the largely sterile triploid forms and their rare sexual progeny. The triploid hybrid F. apennina × F. pratensis proved to be widespread and often highly competitive in Swiss permanent pastures. The majority of these hybrids originated from F. apennina as the seed parent although little or no F. apennina grew nearby. In an experimental setting with ample F. pratensis pollen provided by neighbouring plants, up to 20 % of seeds from open pollinated F. apennina plants were interspecific hybrids; among seeds collected in natural habitats, only 0.35 % were hybrids. At an experimental site at 1 000 m altitude, these triploid hybrids grew much more vigorously than corresponding tetraploid pure F. apennina, confirming their great competitiveness at such altitudes in permanent grasslands. The triploid hybrids were only marginally fertile suggesting that vegetative propagation by rhizomes is the cause of their competitive success in grassland. Moreover, triploid progeny retained the chromosome constitution of their mother plants indicating the possibility of apomixis. Natural triploid F. pratensis × L. perenne hybrids were partially female fertile (a seed set of 0.1 % or less) whereas diploid hybrids did not produce any viable seeds. Progenies of these triploids showed considerable chromosome alterations, such as loss of a genome or recombination due to homoeologous pairing, and only rarely the chromosome constitution of the triploid mother plant was retained. It was concluded that natural triploid interspecific hybrids could expand the range of their progenitor species and might function as bridges transferring genes between them.

With the drastic changes in global climate and the increasing frequency of extreme weather events, abiotic stress poses a significant threat to future food crop production and is a major contributor to crop yield reduction (Ahmad et al., 2010). Wheat, one of the world's primary food crops, is susceptible to both abiotic and biotic stresses at all stages of its growth and development. Numerous studies have indicated that drought stress severely limits the growth and productivity of wheat (Xue et al., 2014; Faran et al., 2019). Therefore, understanding the effects of drought stress on wheat grain germination and developing strategies to mitigate the inhibition of germination caused by drought are crucial for enhancing wheat yield.

Tomato spotted wilt virus (TSWV; species Orthotospovirus tomatomaculae, family Tospoviridae) (Kuhn et al., 2023), is a negative strand RNA-virus containing envelope structures, which makes it unique among plant viruses (de Haan et al., 1991). TSWV ranks among the most destructive plant viruses worldwide. First described in Australia in 1919, TSWV has since attained a global distribution, infecting over 1 000 plant species across more than 85 families, including key agricultural crops such as tomato (Solanum lycopersicum), pepper (Capsicum annuum), groundnut (Arachis hypogaea), and various ornamentals (Parrella et al., 2003; Pappu et al., 2009). Infected plants typically exhibit chlorotic or necrotic spots, wilting, stunted growth, and in severe cases, complete crop failure, resulting in considerable economic losses, particularly in Solanaceous and Asteraceous crops (Roselló et al., 1996; Latham and Jones, 1998).

The Arabidopsis heme oxygenase 1 (HY1) plays a significant role in the signal transduction of abiotic stimuli and hormonal response. To characterize the HY1 promoter, an approximately 1.8 kb of it (pHY1, -1666 to +132) and its deletion fragments (5D1, -1528 to +132; 5D2, -1109 to +132; 5D3, -688 to +132; 5D4, -169 to +132; 3D1, -1666 to +100; 3D2, -1666 to -1; and 3D3, -1666 to -170), were fused to the β-glucuronidase (GUS) reporter gene and transformed into Arabidopsis. The transgenic plants were subjected to several environmental stimuli (especially to mild salinity, iron deficiency, and mercury exposure). The results show that the region from +1 to +100 in the 5'-untranslated region were essential for HY1 basal promoter activity. The induced GUS activities under NaCl and H₂O₂ treatments were slowed down by the progressive 5' deletion (from -1666 to -688) and correlated with the reduced numbers of myeloblastosis (MYB) binding sites (MBSs; -1542, -1333, -1078, and -177). The MBS-free promoter construct 5D4 (-169 to +132), however, fully lost the inducibility. Therefore, we propose that the MBS elements existing in the HY1 promoter might be crucial for salinity-induced HY1 up-regulation in an H₂O₂-dependent fashion. Moreover, the regions from -169 to -1 and -688 to -169 were presumed as the regulatory regions of HY1 promoter in response to iron deficiency and mercury exposure, respectively.

Martaban camphor [Cinnamomum parthenoxylon (Jack) Meisn] is a woody tree in India, China, Indonesia, Thailand, and Vietnam and has been widely utilized for commercial purposes. It is threatened due to fragmented habitats, over-deforestation, and oil extraction. To conserve this species, the investigation of genetic diversity and population structure of this species is essential. Herein, we analyzed 192 adult trees from eight populations covering its natural distribution range in Vietnam using ten polymorphic EST-SSR markers. Medium levels of genetic diversity (R = 2.7, H_o = 0.399, H_e = 0.426) and genetic differences between populations (F_st = 0.223) were determined. Two populations, Cuc Phuong and Xuan Nha have undergone recent bottlenecks. These results indicated that anthropogenic activities may be the major factor for the low heterozygosity and influenced the number of alleles in all C. parthenoxylon populations. Clustering analyses revealed three genetic clusters that related to gene flow between different areas. We proposed in situ conservation for some populations with high levels of allelic richness, genetic diversity, or private alleles. The collecting of the seeds of the remaining populations for ex-situ conservation could be performed.

Flavonoids are a class of phenolic compounds that are widely distributed in nature. They have a variety of physiological and pharmacological activities. They exist in free form or in the form of glycosides. The glycosylation occurs by glycosyltransferases, which is a common modification of plant secondary metabolites and the last step of their biosynthesis. Glycosylation can increase the diversity of the structure and function of flavonoids, and is currently a research hotspot. Based on the classification of flavonoids, this paper describes and summarizes the biotransformation and characteristics of glycosylation modification of flavonoids with different structural types, and describes the effects of enzymatic glycosylation using different types of glycosyltransferases on the biological activity and function of flavonoids depending on sugar connection position, sugar quantity, and type. This paper provides a reference for the development and application of flavonoids glycosylation and glycosyltransferases and also opens up a new direction for plant breeding.

Image-derived phenotyping at individual plant level can provide more accurate and more comprehensive information than manual measuring for quantitative traits related to canopy growth in field environment. Aims of this study were to: (i) assess smartphone image-derived canopy parameter at early stage of sunflower, and (ii) to evaluate performance of predictive models for morphological and biomass traits related to canopy growth using smartphone image-derived parameter. Original top-view image datasets taken with a smartphone camera were processed, and necessary information was extracted with image analysis software developed using fuzzy c-means clustering algorithm. Canopy cover rate per plant (CCR) was not only the relative value but also image-derived phenotyping feature. CCR were significantly and positively correlated (r ≧ 0.90; **P < 0.01) with plant height, total leaf area per plant, plant dry mass, aboveground plant dry and leaf dry mass, respectively. Ground measured and predicted values from linear regression model for plant height, total leaf area per plant, plant dry mass, aboveground total dry mass, leaf dry mass per plant with CCR showed an accurate prediction with high coefficients of determination (R ) of more than 0.8063, respectively. The present study documented the robustness of predictive models using several metrics.

The seasonal patterns of changes in the content of lipophilic antioxidants β-carotene (β-Car), zeaxanthin (Zx), α-tocopherol (α-Toc), plastoquinone (PQ)/plastoquinol (PQH₂) were studied in the assimilating shoots of evergreen shrub Ephedra monosperma J.G. Gmel ex C.A. Mey under natural conditions of Central Yakutia. The shortening of the photoperiod and the seasonal decrease in temperature induced a 1.4-fold increase in α-Toc content. The fall in the average daily temperature from 0.1 to -8.1°C in October led to a decrease in the content of β-Car as a result of the accumulation of rhodoxanthin (Rhd). In this period a sharp increase in the content of Zx retained overnight was also detected. In winter, elevated content of Zx and α-Toc persisted. During September, the content of PQH₂ increased by 2.5 times and PQ by 1.4 times (compared to July). The beginning of exposure to freezing average daily temperatures from -3 to -5°C led to the depletion of the total PQ pool by 18%. However, the content of PQ_tot in the winter months was 1.5 times higher than at the end of July. The results revealed different timing and temperature ranges of variation for individual antioxidants during the development of frost resistance in ephedra.

Background: Tomato plants exposed to salinity stress may experience dynamic changes in root growth and cell wall (CW) composition and structure. Aims: Here, we determined the CW composition and cation-exchange capacity (CEC) of two tomato cultivars (Daniela, salt-tolerant and Naomi, salt-sensitive) as well as their growth and root characteristics. Methods: Seedlings of the tomato cultivars were exposed to six NaCl plus CaCl₂ concentrations hydroponically, root growth and CW chemical composition were measured. Results: The root growth of Naomi was adversely (P ≤ 0.05) reduced at the elongation zone, but there was little change in the chemical composition of the CW under salinity. A marked reduction occurred in the CW-constituting polysaccharides of Naomi relative to Daniela, whether at the 8.00 dS m^-1 NaCl treatment or its combination with CaCl₂. For both root zones, CW viscosity was better enhanced under NaCl and CaCl₂ combinations, but the contents of uronic acid across the CW constituents increased under sole treatment with CaCl₂ at the mature root zone of Naomi. The root CW CEC increased (P ≤ 0.05) with increases in the ionic concentration of the external solution. Salt concentrations at 8.0 dS m^-1 NaCl or 8.0 dS m^-1 NaCl + CaCl₂ increased (P ≤ 0.05) the CEC of the CW, especially for Daniela. Conclusions: The overall results showed that CaCl₂ could enhance some tolerance in CW polysaccharides of tomato under salinity stress. The salt-tolerant Daniela with higher CW and ionic contents had superior stability in cell structure under salt stress.

Garlic mustard (Alliaria petiolata) is an herbaceous biennial plant native to Europe. In Ukraine, in addition to becoming a serious invader, garlic mustard can serve as a host to several viruses, which may affect agricultural crops. In view of this, the purpose of the study was to identify the virome of garlic mustard growing in Ukraine. Plant samples collected in Kyiv regions were tested for the presence of cucumber mosaic virus (CMV), turnip mosaic virus (TuMV), turnip yellow mosaic virus (TYMV), watermelon mosaic virus II (WMV), and turnip crinkle virus (TCV) by serological and/or molecular methods. According to the results found in the present study, symptomatic A. petiolata obtained in 2021 were infected with CMV (60%), TuMV (20%), or co-infected with CMV + TuMV (20%). TYMV, WMV II, and TCV were not detected in any of the collected samples. The cDNA fragments encoded the coat protein (CP) gene of CMV and TuMV were sequenced and named as CMV-Ap and TuMV-Ap, respectively. In phylogenetic analysis, the CMV-Ap closely resembled the German isolate MW582807 (Sarracenia sp.), with 99.8% nucleotide identity and belongs to subgroup II of CMV. In the phylogenetic tree, TuMV-Ap clustered with isolates AP017803, AP017764, AP017791, and JQ073722, and represented the highest identity (98.6%) to Iranian isolate IRNTRa9 (AP017803) from Rapistrum rugosum and Turkish isolate TUR49 (AP017872) from Raphanus raphanistrum. The sequences of CMV-Ap and TuMV-Ap were deposited in the GenBank under Accession Numbers MZ540213 and OM799323, respectively. The results obtained in the study indicate the important role of infected garlic mustard as alternative host and natural reservoir of CMV and TuMV from which these economically important viruses can spread to other wild and cultivated plants. This is the first molecular evidence of TuMV infection in A. petiolata from Ukraine.

This study investigated the impacts of acid rain stress on Akebia trifoliata and the mitigation effects of exogenous curcumin (CUR) using integrated physiological, anatomical, and transcriptomic analyses. Acid rain stress significantly decreased chlorophyll content (total chlorophyll by 64.8%), leaf epidermal thickness (upper and lower epidermis by 58.9 and 35.6%), and starch content (by 63.9%), while increasing oxidative stress markers (MDA by 82.6%; ROS production by 345.8%) and content of osmolytes (proline by 64.4%). A. trifoliata counteracted acid rain stress by enhancing superoxide dismutase (SOD) and catalase (CAT) activities, and by modifying leaf anatomical structure (increased mesophyll tissue thickness). CUR application, particularly at 50 μmol/L (CUR50), effectively alleviated damage by maintaining leaf structural integrity and promoting growth recovery. Transcriptomic analysis revealed 993 differentially expressed genes between CUR50-treated vs. acid rain-stressed plants, primarily enriched in the plant hormone signal transduction and phenylpropanoid biosynthesis pathways. These results demonstrate that CUR mitigates acid rain stress through coordinated physiological adaptations and transcriptional reprogramming of stress-responsive pathways. This study provides a theoretical basis for cultivating A. trifoliata and implementing phytoremediation strategies in acid rain-affected regions.