Search Results (449)

Detecting power transformer winding degradations at an early stage is very important for the safe operation of nuclear power plants. Most transformer failures are caused by insulation breakdown; the winding turn-to-turn short circuit fault is frequently encountered. Experience has shown that routine testing techniques, e.g., winding resistance, leakage inductance, and sweep frequency response analysis (SFRA), are not sensitive enough to identify minor turn-to-turn short defects. The SFRA technique is effective only if the fault is in such a condition that the flux distribution in the core is prominently distorted. This paper proposes the frequency domain reflectometry (FDR) technique for detecting and locating transformer winding defects. FDR measures the wave impedance and its change along the measured windings. The wire over a plane model is selected as the transmission line model for the transformer winding. The effectiveness is verified through lab experiments on a twist pair cable simulating the transformer winding and field testing on a real transformer. The FDR technique successfully identified and located the turn-to-turn short fault that was not detected by other testing techniques. Using FDR as a complementary tool for winding condition assessment will be beneficial. Full article

Using light-emitting diodes (LEDs), we examined how different light wavelengths influence the hypersensitive response (HR) in tobacco plants infected with Pseudomonas syringae pv. tomato (Pst). Pst-infiltrated plants exhibited greater resistance to Pst infection under green and blue light compared to white and red light, as indicated by reduced HR-associated programmed cell death, lower H₂O₂ production, and up to 64% reduction in membrane damage. During the late stage of HR, catalase and ascorbate peroxidase activities peaked under green and blue LEDs, with 5- and 10-fold increases, respectively, while superoxide dismutase activity was higher under white and red LEDs. Defense-related genes CHS1, PALa, PR1, and PR2 were more strongly induced by white and red light. The plants treated with green or blue LEDs during Pst infection prompted faster degradation of phototoxic Mg-porphyrins and exhibited smaller declines in F_v/F_m, electron transport rate, chlorophyll content, and LHCB expression compared to those treated with white or red LEDs. By contrast, the induction of the chlorophyll catabolic gene SGR was 54% and 77% lower in green and blue LEDs, respectively, compared to white LEDs. This study demonstrates that light quality differentially affects Pst-mediated HR, with green and blue light more effectively suppressing HR progression, mainly by reducing oxidative stress through enhanced antioxidative capacity and mitigation of photosynthetic impairments. Full article

The floral transition in Chinese cabbage (Brassica rapa ssp. pekinensis) is governed by a complex interplay of gene expression and hormonal regulation. Temporal transcriptome profiling was conducted across three developmental stages: pre-bolting (PBS), bolting (BS), and flowering stages (FS), to investigate the underlying molecular mechanisms. A total of 7092 differentially expressed genes (DEGs) were identified, exhibiting distinct expression trajectories during the transition. Moreover, functional enrichment analyses revealed strong associations with plant hormone signaling, MAPK pathways, and developmental regulation processes. Key flowering-related genes, such as BrFLM, BrAP2, BrFD, BrFT, and BrSOC1s displayed antagonistic expression patterns. Hormonal pathways involving auxin, ABA, ET, BR, GA, JA, CK, and SA showed stage-dependent modulation. Further, orphan genes (OGs), especially EARLY FLOWERING 1 (EF1), showed significant upregulation during the transition, which exhibited 1.84-fold and 1.93-fold increases at BS and FS compared to PBS, respectively (p < 0.05). Functional validation through EF1 overexpression (EF1OE) in Arabidopsis consistently promoted early flowering. The expression levels of AtFT and AtSOC1 were significantly upregulated in EF1OE lines compared to wild-type (WT) plants. The findings contribute to understanding the coordinated genetic and hormonal events driving floral development in Chinese cabbage, suggesting EF1 as a candidate for bolting resistance breeding. This work also expands the existing regulatory framework through the successful integration of OGs into the complex floral induction system of Brassica crops. Full article

Powdery mildew caused by Sphaerotheca fusca poses a significant threat to cucumber (Cucumis sativus L.) production worldwide, underscoring the need for sustainable disease management strategies. This study investigates the potential of L-lysine, abundantly produced by Bacillus subtilis M 320 (BSM320), to prime systemic acquired resistance (SAR) pathways in cucumber plants. Liquid chromatography–mass spectrometry analysis identified L-lysine as the primary bioactive metabolite in the BSM320 culture filtrate. Foliar application of purified L-lysine significantly reduced powdery mildew symptoms, lowering disease severity by up to 92% at concentrations ≥ 2500 mg/L. However, in vitro spore germination assays indicated that L-lysine did not exhibit direct antifungal activity, indicating that its protective effect is likely mediated through the activation of plant immune responses. Quantitative reverse transcription PCR revealed marked upregulation of key defense-related genes encoding pathogenesis-related proteins 1 and 3, lipoxygenase 1 and 23, WRKY transcription factor 20, and L-type lectin receptor kinase 6.1 within 24 h of treatment. Concurrently, salicylic acid (SA) levels increased threefold in lysine-treated plants, confirming the induction of an SA-dependent SAR pathway. These findings highlight L-lysine as a sustainable, residue-free priming agent capable of enhancing broad-spectrum plant immunity, offering a promising approach for amino acid-based crop protection. Full article

Asian chestnut gall wasp (ACGW) (Dryocosmus kuriphilus Yasumatsu), native to China, is an invasive pest that causes significant economic losses in Castanea species. While some cultivars show full resistance by inhibiting insect development in buds, the underlying defense mechanisms remain unclear. In this study, the accumulation and distribution of hydrogen peroxide (H₂O₂) were investigated in dormant buds of chestnut cultivars that are resistant and susceptible to D. kuriphilus by using the 3,3′-diaminobenzidine (DAB) staining method. Buds were examined under a stereomicroscope during key stages of pest development, including oviposition, transition from egg to larva, gall induction, and gall development. Baseline levels of H₂O₂ were detected in all buds; however, these levels varied among cultivars, with resistant cultivars exhibiting lower basal levels. The degree of H₂O₂ accumulation was found to vary depending on plant–insect interaction, physiological processes, and cultivar-specific traits. Histochemical staining revealed that brown spots indicative of H₂O₂ accumulation were concentrated in the vascular bundles of leaf primordia and in the apical regions. In resistant hybrid cultivars, the defense response was activated at an earlier stage, while in resistant Castanea sativa Mill. cultivars, the response was delayed but more robust. Although consistently high levels of H₂O₂ were observed throughout the pest interaction in susceptible cultivars, gall development was not inhibited. During the onset of physiological bud break, increased H₂O₂ accumulation was observed across all cultivars. This increase was associated with endodormancy in susceptible cultivars and with both defense mechanisms and endodormancy processes in resistant cultivars. These findings highlight the significant role of H₂O₂ in plant defense responses, while also supporting its function as a multifunctional signaling molecule involved in gall development and the regulation of physiological processes. Full article

Clubroot disease, caused by the soil-borne pathogen Plasmodiophora brassicae, poses a severe threat to the global production of Brassicaceae crops, including radish (Raphanus sativus L.). Although resistance breeding is an important method for sustainable disease management, the molecular mechanism underlying clubroot resistance remains elusive in radish compared to other Brassicaceae species. In this study, 52 radish inbred lines were screened for disease responses following P. brassicae inoculation, with the resistant line T6 and the susceptible line T14 selected for transcriptome analysis. RNA-Seq was performed at 10, 20, and 30 days post inoculation (DPI) to elucidate transcriptional responses. The susceptible line T14 exhibited a higher number of differentially expressed genes (DEGs) and persistent upregulation across all time points, indicating ineffective defense responses and metabolic hijacking by the pathogen. In contrast, the resistant line T6 displayed temporally coordinated defense activation marked by rapid induction of core immune mechanisms: enhanced plant–pathogen interaction recognition, MAPK cascade signaling, and phytohormone transduction pathways, consistent with effector-triggered immunity priming and multilayered defense orchestration. These findings indicate that resistance in T6 could be mediated by the rapid activation of multilayered defense mechanisms, including R gene-mediated recognition, MAPK-Ca²⁺-ROS signaling, and jasmonic acid (JA) pathway modulation. The outcomes of this study would not only facilitate clarifying the molecular mechanism underlying clubroot resistance, but also provide valuable resources for genetic improvement of clubroot resistance in radish. Full article

Plant-growth-promoting fungi (PGPF) play a central role in promoting sustainable agriculture by improving plant growth and resilience. The aim of this literature review is to survey the impacts of Trichoderma spp. and Penicillium spp. on various agricultural and horticultural plants. The information provided in this manuscript was obtained from randomized control experiments, review articles, and analytical studies and observations gathered from numerous literature sources such as Scopus, Google Scholar, PubMed, and Science Direct. The keywords used were the common and Latin names of various agricultural and horticultural species, fungal endophytes, plant-growth-promoting fungi, Trichoderma, Penicillium, microbial biostimulants, and biotic and abiotic stresses. Endophytic fungi refer to fungi that live in plant tissues throughout part of or the entire life cycle by starting a mutually beneficial symbiotic relationship with its host without any negative effects. They are also capable of producing compounds and a variety of bioactive components such as terpenoids, steroids, flavonoids, alkaloids, and phenolic components. Penicillium is extensively known for its production of secondary metabolites, its impact as a bioinoculant to help with crop productivity, and its effectiveness in sustainable crop production. The plant-growth-promotion effects of Trichoderma spp. are related to better absorption of mineral nutrients, enhanced morphological growth, better reproductive potential and yield, and better induction of disease resistance. Both Penicillium spp. and Trichoderma spp. are effective, affordable, safe, and eco-friendly biocontrol agents for various plant species, and they can be considered economically important microorganisms for both agricultural and horticultural sciences. The present review article aims to present the most up-to-date results and findings regarding the practical applications of two important types of PGPF, namely Penicillium spp., and Trichoderma spp., in agricultural and horticultural species, considering the mechanisms of actions of these species of fungi. Full article

Sitosterol (Sito) is a phytosterol with bioactive properties, including reducing atherosclerosis risk and anti-inflammatory and antitumoral effects. However, it can be oxidized by reactive oxygen species such as ozone (O₃), producing oxyphytosterols with harmful effects such as cytotoxicity, oxidative stress, and proatherogenicity. Ozone, a strong oxidant and common pollutant, can alter plant steroid compounds, raising concerns about dietary oxyphytosterol intake. Studies identify β-Secosterol (βSec) as the primary ozone-derived oxyphytosterol from Sito, exhibiting cytotoxic effects on HepG2 human liver tumor cells. This study investigated βSec’s biological effects on two rat liver cell lines: BRL-3A (immortalized) and HTC (tumoral), examining cell death, cell cycle progression, morphology, and cytoskeleton organization. While Sito influenced cell metabolic activity without affecting cell survival or morphology, βSec demonstrated significant cytotoxicity in both cell lines. It induced G0/G1 cell cycle arrest and disrupted cytoskeleton organization, with different implications: BRL-3A cells showed persistent cytoskeletal changes potentially linked to tumor induction, while HTC cells displayed chemoresistance, restoring cytoskeletal integrity and enhancing metastatic potential. These findings reveal βSec’s complex, context-dependent effects, suggesting it may promote tumor-like behavior in non-tumoral cells and resistance mechanisms in cancer cells, contributing to understanding oxyphytosterols’ implications for physiological and pathological conditions. Full article

As an innovative plant protection method in precision agriculture, electrostatic spray technology can increase the droplet coverage area by over 30% coMpared to conventional spraying. This technology not only achieves higher droplet deposition density and coverage but also enables water and pesticide savings while reducing environmental pollution. This study, combining theoretical analysis with experimental validation, reveals the critical role of electrode material selection in induction-based electrostatic spray systems. Theoretical analysis indicates that the Fermi level and work function of electrode materials fundamentally determine charge transfer efficiency, while corrosion resistance emerges as a key parameter affecting system durability. To elucidate the effects of different electrode materials on droplet charging, a coMparative study was conducted on nickel, copper, and brass electrodes in both pristine and moderately corroded states based on the corrosion classification standard, using a targeted mesh-based charge-to-mass measurement device. The results demonstrated that the nickel electrode achieved a peak charge-to-mass ratio of 1.92 mC/kg at 10 kV, which was 8.5% and 11.6% higher than copper (1.77 mC/kg) and brass (1.72 mC/kg), respectively. After corrosion, nickel exhibited the smallest reduction in the charge-to-mass ratio (19.2%), significantly outperforming copper (40.2%) and brass (21.6%). Droplet size analysis using a Malvern Panalytical Spraytec spray particle analyzer (measurement range: 0.1–2000 µm) further confirmed the atomization advantages of nickel electrodes. The volume median diameter (Dv50) of droplets produced by nickel was 4.2–8 μm and 6.8–12.3 um smaller than those from copper and brass electrodes, respectively. After corrosion, nickel showed a smaller increase in droplet size spectrum inhomogeneity (24.5%), which was lower than copper (30.4%) and brass (25.8%), indicating superior droplet uniformity. By establishing a multi-factor predictive model for spray droplet size after electrode corrosion, this study quantifies the correlation between electrode characteristics and spray performance metrics. It provides a theoretical basis for designing weather-resistant electrostatic spray systems suitable for agricultural pesticide application scenarios involving prolonged exposure to corrosive chemicals. This work offers significant technical support for sustainable crop protection strategies. Full article

The GLABROUS1 enhancer-binding protein (GeBP) gene family, a plant-specific class of transcriptional regulators, is involved in multiple biological processes, including the formation of trichomes, plant growth, and environmental adaptation. However, the functional characterization of SlGeBP genes in tomato remains poor, particularly regarding their roles in regulating developmental processes and stress response mechanisms. In this study, 11 SlGeBP family members were identified from the tomato genome and 97 GeBP proteins from six species were classified into three groups. A wide range of elements linked to phytohormone, stress, and plant development were presented on the promoter sequences. Gene expression profile analysis revealed a comprehensive expression during the vegetative and immature fruit development stages. Analysis of the expression level under nine hormones and seven stresses can help us to understand the responsiveness of SlGeBP genes associated with hormone induction and stress tolerance. Subcellular localization analysis exhibited that SlGeBP1 and SlGeBP5 were localized in the nucleus, and the yeast two-hybrid assay confirmed that SlGeBP1 could interact with SlGeBP5. This study will help us to understand the potential function of the SlGeBP family and may establish a basis for further research on phytohormone signaling and stress resistance. Full article

Peanut root rot poses a significant threat to global peanut production. In order to identify the new pathogen of peanut root rot in Shandong province, China, and to screen the effective antagonistic biocontrol strains against the identified pathogen, ten symptomatic plants from a peanut field (10% disease incidence) of Rongcheng were sampled for pathogen isolation. The predominant isolate RC-103 was identified as Ceratobasidium sp. AG-A through morphological characterization and phylogenetic analysis of ITS and RPB2 sequences. Pathogenicity was confirmed via Koch’s postulates. Three potent biocontrol strains, namely Bacillus subtilis LY-1, Bacillus velezensis ZHX-7, and Burkholderia cepacia Bc-HN1, were screened for effective antagonism against isolate RC-103 by dual-culture analysis. Their cell suspensions could significantly inhibit the hyphal growth of isolate RC-103, with the percentage inhibition of 54.70%, 45.86%, and 48.62%, respectively. Notably, the percentage inhibition of 10% concentration of the cell-free culture filtrate of B. subtilis LY-1 was as high as 59.01%, and the inhibition rate of volatile organic compounds of B. cepacia Bc-HN1 was 48.62%. Antagonistic mechanisms primarily involved the induction of hyphal abnormalities. In addition, the culture filtrate of these biocontrol bacteria significantly promoted the growth of peanut and increased the resistance of peanut plants to isolate RC-103, with the biocontrol efficiency reaching 41.86%. In summary, this study identified a novel pathogen of peanut root rot, Ceratobasidium sp. AG-A, which was reported for the first time in China, and screened three highly effective antagonistic biocontrol strains against Ceratobasidium sp. AG-A isolate RC-103, providing the scientific basis to study the epidemiology and management of this disease. Full article

Background: The opportunistic pathogen Staphylococcus aureus causes skin and soft tissue infections that are associated with biofilm formation, and in immunocompromised patients can progress to surgical site infections, pneumonia, bacteremia, sepsis, and even death. Most antibiotics actively damage living, dividing cells on the surface of the biofilm, where there is a high concentration of nutrients and oxygen, while in the depths, where these factors are scarce, slowly growing cells remain. Objectives: The aim of our study was to evaluate the antibiofilm potential of ethyl acetate roots (EtOAcR) and aerial parts (EtOAcAP) extracts from the perennial Bulgarian plant Geum urbanum L. against methicillin-resistant S. aureus (MRSA) NBIMCC 8327. Methods: The effects of both extracts on the expression of biofilm-related genes, icaA and icaD, were investigated. The cytotoxicity of EtOAcR and EtOAcAP on A-375 (human melanoma), A-431 (epidermoid skin cancer) and HaCaT (normal keratinocytes) cell lines, and the induction of apoptosis were determined. Finally, the in vivo skin irritation potential of the most active extract was studied. Results: Both tested extracts inhibited biofilm formation at concentrations that did not affect bacterial growth. Interestingly, the expression of icaA and icaD was upregulated, although the biofilm development was inhibited 72.4–90.5% by EtOAcAP and 18.9–20.4% by EtOAcR at sub-MICs. EtOAcAP extract showed a more favorable cytotoxic profile on non-tumorigenic cells and stronger antineoplastic activity (IC₅₀ = 6.7–14.68 µg/mL) as compared to EtOAcR extract (IC₅₀ = 8.73–23.67 µg/mL). Therefore, a skin irritation test was performed with the EtOAcAP extract at ten-times higher concentrations than the minimum inhibitory one, and, resultantly, the primary irritation index was equal to zero (no skin irritation observed). Conclusions: The EtOAcAP extract was proven to be an effective antistaphylococcal agent with favorable skin tolerance. The extract showed strong antineoplastic activity and antibiofilm effect at sub-MICs, which outlines new prospects for its development as a natural product for specific skin applications in medical practice. Full article

Sucrose phosphate synthase (SPS) is a rate-limiting enzyme in plant sucrose biosynthesis. However, the SPS gene family in luffa remains unidentified, and its functional involvement in sugar metabolism is unexplored. Here, we present the first genome-wide identification and functional analysis of the LaSPSs in luffa. We identified nine LaSPS genes, characterized their physicochemical and evolutionary properties, and analyzed their expression patterns in different tissues and response to ethylene and drought treatments. Nine tandem-duplicated LaSPS genes formed four clusters (T1(1/2), T2(3/4), T3(5/6), T4(7–9)) with conserved architectures. RNA-seq analysis indicated a ubiquitous downregulation of LaSPS genes in senescing luffa, wherein sucrose content correlated significantly with all LaSPS members except LaSPS1/2. Exogenous ethylene substantially repressed LaSPSs transcription, while 1-methylcyclopropene (1-MCP) treatment showed induction. Notably, LaSPS3/4 displayed high activation under drought stress. Functional validation via heterologous expression in tobacco confirmed that LaSPS3/4 positively regulates drought resistance. In summary, this study provides a novel perspective for the in-depth investigation of the molecular evolutionary mechanism of the LaSPS gene family and its biological functions in luffa. Full article

The effects of wound healing on crop stand and productivity were examined on the potato (Solanum tuberosum L.) cultivars Alturas (Alt), Russet Burbank (RB), and Clearwater Russet (CW). Tuber yields increased linearly with an advancing wound healing period irrespective of the cultivar (R² = 0.91). In contrast to unhealed controls, RB and CW wound-healed for 8 days produced a 6% and 8% greater yield, respectively, while a shorter wound healing period of 2 days increased Alt yield by 7%. Increases in tuber yield, a consequence of enhanced specific tuber weight across wound healing periods, contributed towards increased relative crop value in Alt (13%), RB (22%), and CW (19%). In further lab evaluations, Alt exhibited increased desiccation resistance and was associated with an earlier induction (24 h post-wounding) of feruloyl transferase (FHT) compared to CW and RB. Since FHT facilitates suberin and wax development, delayed FHT induction likely promoted fresh-weight loss in CW and RB compared to Alt. Enzymatic evaluations to assess the production of reactive oxygen species to protect fresh-cut seed found that RB had the highest activities of superoxide dismutase and peroxidase. This study demonstrates the broad benefits of planting wound-healed seed while highlighting opportunities to improve best practices and genetic improvement for wound healing response. Full article

Lanzhou lily is a plant native to China with high edible, medicinal, and ornamental value that is relatively susceptible to Fusarium wilt. In this study, the application of Trichoderma longibrachiatum SMF2 (TlSMF2) effectively controlled Lanzhou lily wilt disease caused by Fusarium oxysporum and F. solani. TlSMF2 and the antimicrobial peptaibols trichokonins (TKs) produced by TlSMF2 inhibited the mycelial growth and spore germination of these two pathogens. Transcriptome analysis revealed that the TKs-induced defense responses of Lanzhou lily were mainly related to the production of plant hormones and defense enzymes. In detail, TKs treatment increased the levels of salicylic acid (SA) and jasmonic acid (JA) and the expression of their related genes and upregulated the activities of chitinase and phenylalanine ammonia-lyase (PAL). Moreover, TKs caused the induction of LzWRKY26 and LzWRKY75, which is highly homologous to LrWRKY3 that positively regulates Lilium regale resistance to F. oxysporum. LzWRKY26 expression was also induced by SA and MeJA treatments and F. oxysporum infection, which was consistent with the findings that many cis-acting elements associated with phytohormones and stress responses are present in the promoter region of LzWRKY26. Therefore, the biocontrol mechanisms of TlSMF2 against Lanzhou lily wilt disease involve substrate competition and toxicity against pathogens, as well as the induction of systemic resistance in plants. Our results highlight a promising biological control agent for soil-borne fungal diseases and offer deeper insights into the biocontrol mechanisms of TlSMF2. Full article