Search Results (337)

Wildfires are a recurring dry-season hazard in northern Thailand, contributing to severe air pollution and trans-boundary haze. However, the region lacks the ground-based measurements necessary for monitoring Live Fuel Moisture Content (LFMC), a key variable influencing vegetation flammability. This study presents a preliminary framework for near-real-time (NRT) LFMC estimation using Sentinel-2 multispectral imagery. The system integrates normalized vegetation and moisture-related indices, including the Normalized Difference Vegetation Index (NDVI), the Normalized Difference Infrared Index (NDII), and the Moisture Stress Index (MSI) with an NDVI-derived evapotranspiration fraction (ETf) within a heuristic modeling approach. The workflow includes cloud and shadow masking, weekly to biweekly compositing, and pixel-wise normalization to address the persistent cloud cover and heterogeneous land surfaces. Although currently unvalidated, the LFMC estimates capture the relative spatial and temporal variations in vegetation moisture across northern Thailand during the 2024 dry season (January–April). Evergreen forests maintained higher moisture levels, whereas deciduous forests and agricultural landscapes exhibited pronounced drying from January to March. Short-lag responses to rainfall suggest modest moisture recovery following precipitation, although the relationship is influenced by additional climatic and ecological factors not represented in the heuristic model. LFMC-derived moisture classes reflect broad seasonal dryness patterns but should not be interpreted as direct fire danger indicators. This study demonstrates the feasibility of generating regional LFMC indicators in a data-scarce tropical environment and outlines a clear pathway for future calibration and validation, including field sampling, statistical optimization, and benchmarking against global LFMC products. Until validated, the proposed NRT LFMC estimation product should be used to assess relative vegetation dryness and to support the refinement and development of future operational fire management tools, including early warnings, burn-permit regulation, and resource allocation. Full article

Low Nitrogen Use Efficiency (NUE) remains a critical agricultural challenge, as an estimated 50–70% of applied nitrogen (N) is lost, resulting in negative environmental impacts and reduced crop production. To elucidate molecular mechanism controlling NUE in tomato (Solanum lycopersicum), we conducted a comprehensive genomic, transcriptomic, and functional analysis of the NPF, NRT2, and AMT transporter families under high-N commercial supply conditions. Our integrated analysis identified a shoot-to-root signaling mechanism where the plant’s metabolic performance systematically regulates N transport capacity. Under N sufficiency, the shoot exhibited reduced N assimilation, evidenced by NO₃⁻ accumulation (increased by 55.7%) and reduced Nitrate Reductase (NR) and Glutamine Synthetase (GS) activities (54.0% and 43.2% reduction, respectively), which correlated with a 42.3% reduction in chlorophyll synthesis capacity. This reduction in metabolic demand systematically triggered the downregulation of the key long-distance SlNPF transporters, SlNPF2.13 and SlNPF7.3, restricting N translocation and promoting significant root N accumulation (increased by 41.8%). Our data established that the leaf metabolic state is the systemic regulator of N transport and identified SlNPF2.13 and SlNPF7.3 as pivotal molecular checkpoints. These findings indicate that the manipulation of these transporters could serve as a valuable tool in molecular breeding programs to significantly enhance NUE in commercial tomato varieties. Full article

Soil salinity is a serious abiotic stressor threatening global agriculture, currently affecting nearly 20% of irrigated land, with projections suggesting that almost 50% of cultivated areas may be impacted by 2050. Plant growth-promoting rhizobacteria (PGPR) and Silicon (Si) have been widely investigated for their individual roles in improving plant tolerance to salinity, yet their combined application—particularly using Si nanoparticles (SiNPs), remains underexplored. This review synthesizes current knowledge on PGPR, SiNPs, and their synergistic effects in mitigating salinity stress, with emphasis on physiological, biochemical, and molecular mechanisms. Special attention is given to Si-mediated regulation of stress-responsive genes (e.g., RD29B, DREB2b, RAB18, HKT1, WRKY TFs, CAT, POD) and PGPR-induced gene expression (e.g., GmST1, GmLAX3, NHX1, NRT2.2, GR), which are directly linked to ion homeostasis, osmolyte accumulation, and antioxidant activation. In addition, crop-specific case studies and emerging molecular insights are highlighted to demonstrate practical applications. Despite these promising findings, significant challenges remain, including the stability of nanoformulations, microbial compatibility, and the lack of field-scale validation under diverse agro-climatic conditions. This review highlights knowledge gaps and briefly outlines future directions for the integrated use of PGPR and SiNPs as sustainable strategies to enhance crop resilience under salinity stress. Full article

Nicotinamide adenine dinucleotide (NAD⁺) serves as a critical cofactor in redox reactions and metabolic transformations catalyzed by NAD-dependent enzymes and is essential for bacterial survival and virulence. The biosynthesis of NAD⁺ in the cariogenic pathogen Streptococcus Sobrinus (S. sobrinus), a pivotal participant in oral cavities of children and adolescents with a history of caries, has yet to be explored. Bioinformatics, genetics, and biochemical techniques were used to identify NAD⁺ biosynthesis pathways and corresponding regulator in S. Sobrinus. S. sobrinus lacks de novo NAD⁺ synthesis pathway but comprises NA and Nam salvage pathway I (PncA-PncB-NadD-NadE) and PnuC-NadR salvage pathway III. NiaY and PnuC were involved in the salvage pathways. N-terminal domain of SsNrtR regulator was identified as DNA-binding domain binding to the pnuC and pncB probe, and addition of ADP-ribose reversed the binding of SsNrtR to the target promoters to regulate NAD⁺ salvage pathways. C-terminal domain of SsNrtR was non-catalytic, consistent with loss of Nudix motif conservation. Furthermore, the abrogation of niaR compromised multiple pathogenic traits, including cellular proliferation, acidogenesis, and the architecture/mechanical integrity of biofilms. Consequently, this mutant exhibited attenuated virulence in a rat caries model. Our findings conclusively demonstrate that SsNrtR-mediated regulation of NAD⁺ homeostasis is a critical determinant of the cariogenic potential of S. sobrinus. This study identifies SsNrtR as a previously uncharacterized NAD⁺-responsive regulator that integrates metabolic homeostasis with the control of virulence in Streptococcus sobrinus. These findings elucidate a novel metabolic–virulence regulatory axis in this species and position SsNrtR as a promising target for the development of anti-caries interventions. Full article

Ozone density at cold-point mesopause (O3-CPM) can provide information on long-term atmospheric trends. Compared to ground-level ozone, O3-CPM is not only adversely affected by chemical substances emitted from human activities but is also regulated by solar radiation. Therefore, an accurate prediction of O3-CPM is necessary. However, it is difficult for traditional forecasting methods to predict the main trends and seasonal characteristics of ozone time series while capturing the random components and noise of O3-CPM. In order to improve the prediction accuracy of O3-CPM, this paper proposes a hybrid SSA-SARIMA-GSVR model based on the Singular Spectrum Analysis (SSA) method, which combines the Seasonal Autoregressive Integrated Moving Average Model (SARIMA) and the Gray Wolf Algorithm Optimized Support Vector Regression Algorithm (GSVR). First, the O3-CPM sequence is decomposed using SSA, and the concept of reconstruction threshold (RT) is introduced to categorize the decomposed singular values into two classes. The categorized RT reconstructed sequences containing periodic features and major trends are fed into the SARIMA model for prediction, and the N-RT reconstructed sequences (original sequence N minus RT reconstructed sequence) containing stochastic components and nonlinear features are fed into the GSVR model for prediction. The final prediction results are obtained by superimposing the outputs of these two models. The results confirm that, compared to various commonly used time series forecasting models such as Long Short-Term Memory (LSTM), Informer, SVR, SARIMA, GSVR, SSA-GSVR, and SSA-SARIMA models, the proposed SSA-SARIMA-GSVR hybrid prediction model has the lowest error evaluation metrics, enabling accurate and efficient prediction of the O3-CPM time series. Specifically, the proposed model achieved an RMSE of 0.26, MAE of 0.212, and R² of 0.987 on the test set, outperforming the best baseline model (SARIMA) by 45.8%, 42.1%, and 3.1%, respectively. Full article

Nitrogen assimilation is vital for apple growth, yield, and quality, with nitrate reductase (NIA), nitrite reductase (NIR), glutamine synthetase (GS), and glutamate synthase (GOGAT) serving as key regulatory enzymes. This study systematically identified these four gene families in apple (Malus domestica) through genome-wide analysis and examined their expression patterns under nitrate treatment. In total, 13 genes were identified, 2 MdNIAs, 1 MdNIR, 7 MdGSs, and 3 MdGOGATs, with gene lengths ranging from 2577 to 27736 base pairs (bp); MdGLT1A had the longest coding sequence (6627 bp). The encoded proteins contained 355–2208 amino acids, with predicted isoelectric points (pIs) between 5.55 and 6.63. Subcellular localization analysis predicted distinct compartmentalization: MdNIA1A in peroxisomes; MdGS1 in the cytosol; MdNIR1, MdGS2, and MdGLU1 in chloroplasts; and MdGLT1 in mitochondria/chloroplasts. Functional site prediction revealed multiple phosphorylation and glycosylation sites, with ATP/GTP-binding motifs present only in certain MdGOGAT proteins. Protein interaction analysis suggested close associations among these genes and possible interactions with NRT2.1/2.2. Chromosomal mapping showed their distribution across eight chromosomes, while promoter analysis identified diverse cis-acting regulatory elements (e.g., ABRE and G-box). Under nitrate treatment (0–12 h), these genes exhibited distinct expression dynamics: MdNIA1A and B were rapidly induced (0–6 h) and maintained high expression; MdNIR1 peaked at 6 h and then declined; MdGS1.1B was activated after 6 h; and MdGS2A, MdGLU1, and MdGLT1A/B peaked at 6 h before decreasing. Therefore, these results elucidate the structural and functional divergence of nitrogen assimilation genes in apple and provide a basis for understanding nitrogen utilization mechanisms and developing nitrogen-efficient breeding strategies. Full article

Plants continuously adapt to dynamic environmental conditions, which include abiotic stress such as drought, salinity, and high temperature. Translocation, availability, and uptake of essential nutrients are suggested to be disrupted, thereby impairing growth, development, and productivity of the plant. The interplay between the root architecture, membrane transporters, and hormonal regulation is suggested to have efficient nutrient acquisition. For mediating nutrient uptake and redistribution under abiotic stress conditions, transporter proteins such as nitrate (NRT), ammonium (AMT), phosphate (PHT), and potassium (HAK) families play a crucial role for the major essential elements (N, P, K). Abiotic stress triggers specific transcriptional and post-transcriptional regulation of these transporters, modulating their activity in response to external nutrient availability. Under nutrient-deficient conditions, phytohormones such as abscisic acid (ABA), cytokinin, and ethylene play a pivotal role in orchestrating plant responses. Moreover, the plant stress tolerance is suggested to be influenced by stress-induced signalling mechanisms, which are mediated by reactive oxygen species (ROS). The current review synthesizes current knowledge of nutrient dynamics under abiotic stress, focusing on the molecular mechanisms governing transporter regulation and phytohormonal crosstalk. By unravelling these complex regulatory networks, this article aims to pave the way for sustainable agricultural practices. Full article

Background: Insomnia is strongly associated with stimulant use across various populations and for a wide range of substances. It represents a significant clinical problem among individuals with stimulant use disorders, yet treatment guidelines for this specific population are limited. This gap underscores the need for a systematic review to analyze the pharmacological and non-pharmacological treatments for insomnia in individuals with stimulant use disorders. The aim of this review is to determine the efficacy, safety, and limitations of these approaches and their impact on psychiatric symptoms, stimulant use, and adverse events. Methodology: A systematic review was conducted through January–July 2025 using PubMed, Scopus, and Web of Science. The review focused on the management of chronic insomnia associated with stimulant use, including substances such as amphetamines, methylphenidate, nicotine, caffeine, and cocaine. The systematic review was structured in accordance with the PRISMA guidelines, and identified studies were assessed by title/abstract and full-text evaluation. Results: A total of twenty studies were included in the systematic review. Seven studies examined pharmacological interventions, including modafinil, naltrexone/buprenorphine-naloxone, varenicline, combination NRT, and ramelteon. Thirteen studies investigated non-pharmacological approaches, including Cognitive Behavioral Therapy (CBT), Repetitive Transcranial Magnetic Stimulation (rTMS), Electrical Vestibular Nerve Stimulation (VeNS), maximal strength training, electroacupuncture (EA), and probiotics. The majority of interventions demonstrated positive outcomes in reducing insomnia severity, with some participants achieving non-clinical levels. Commonly reported clinical symptoms related to insomnia included difficulty initiating or maintaining sleep, early morning awakening, and sleep dissatisfaction. Conclusions: Both pharmacological and non-pharmacological interventions showed promise. However, the lack of validated guidelines underscores the need for integrated therapeutic approaches that address the complex comorbidity of insomnia, stimulant use, and co-occurring psychiatric conditions. Full article

Salix suchowensis is an ideal model organism for investigating nitrogen (N) transport mechanisms due to its low N-input requirements. Accurate quantification of gene expression is essential for elucidating these processes, with quantitative real-time PCR (RT-qPCR) being the preferred method. However, the identification of stable reference genes for normalization in Salix suchowensis under varying N conditions remains unresolved. In this study, thirteen commonly employed candidate reference genes were evaluated across root, stem, and leaf tissues, under four N treatments (NH₄NO₃, NH₄⁺, NO₃⁻, and N deficiency). Five genes (UBQ1, UBQ3, 18S, H2A2, and H2B2) were excluded due to poor amplification efficiency or irregular melting curves. The remaining eight genes were further assessed for expression stability using the geNorm, NormFinder, and BestKeeper algorithms. Integrated ranking via RefFinder identified EF1α, EFβ, and αTUB as the most stable reference genes. GeNorm analysis suggested that two reference genes were sufficient for reliable normalization. Validation using the N-responsive gene SsAMT1 and SsNRT2 confirmed the stability of EF1α, EFβ, and αTUB as suitable reference genes. Based on comprehensive stability assessments and experimental validation, we recommended EF1α + αTUB as optimal reference gene pairs for RT-qPCR normalization under varying N conditions. Furthermore, the consistent expression of EF1α and αTUB across nine willow genotypes highlighted their broader applicability within Salix species. This study provides valuable methodological guidance for advancing molecular research on N transport in woody perennial plants. Full article

Efficient allocation of mineral nutrients and photoassimilates is essential for grain development in rice. However, the transcriptional programs governing nutrient transport at key reproductive stages remain largely unresolved. Here, we performed a comprehensive transcriptome analysis of rice (Oryza sativa L.) across spatial (nodes, roots, and five other tissues) and temporal (seven reproductive stages) dimensions to elucidate the molecular basis of nutrient transport and allocation. RNA-seq profiling of node I identified stage-specific gene expression patterns, with the grain filling stage marked by strong induction of transporters involved in mineral allocation (e.g., OsYSL2, OsZIP3, OsSULTR3;3, SPDT) and carbohydrate distribution (e.g., OsSWEET13, OsSWEET14, OsMST6). Comparative analysis with the neck-panicle node (NPN) and root revealed tissue-specific regulatory networks, including nitrate (OsNRT1.1A, OsNRT2.3) and phosphate (OsPHT1;4, OsPHO1;3) transporters enriched at the grain filling stage. Root expression of Cd/As-related transporters (OsNRAMP5, OsCd1, OsLsi1, OsLsi2, OsLsi3) during grain filling highlights the contribution of belowground uptake to grain metal accumulation. Together, our study establishes a spatiotemporal atlas of nutrient transporter gene activity during rice reproductive development and identifies candidate genes regulating upward and lateral nutrient allocation. These findings provide insights into improving nutrient use efficiency and reducing toxic metal accumulation in rice grains through targeted manipulation of nodal and root transport systems. Full article

Bluetongue virus belongs to the Reoviridae family, which causes morbidity in ruminants. Herein, we report the full-length genome sequence of a recombinant BTV strain of serotype 1 (YNDH/103/2013) isolated from sentinel cattle in Yunnan Province, China, in 2013. To identify and understand the characteristics of YNDH/103/2013, we screened closely related viruses using Simplot 3.5.1 software and conducted verification via phylogenetic analysis using MEGA 11.0.13 software. Phylogenetic analysis and segment examination showed that the YNDH/103/2013 strain likely originated from multiple recombination events involving prevalent strains such as Y863, NRT37/ABT/HSR, and YTS-4 in China and India. The genome of BTV-1/YNDH/103/2013 derives from at least three reassortments with these strains, showing recombination breakpoints mainly in segments 4, 6, 8, and 9. This study improves our understanding of the origin and spread of BTV-1 in China. Full article

N, as plants’ most essential nutrient, profoundly shapes root system architecture (RSA), with LRs being preferentially regulated. This review synthesizes the intricate molecular mechanisms underpinning N sensing, signaling, and its integration into developmental pathways governing LR initiation, primordium formation, emergence, and elongation. We delve deeply into the roles of specific transporters (NRT1.1, nitrate transporter 2.1 (NRT2.1)), transcription factors (Arabidopsis nitrate regulated 1 (ANR1), NLP7, TGACG motif-binding factor (TGA), squamosa promoter-binding protein-like 9 (SPL9)) and intricate hormone signaling networks (auxin, abscisic acid, cytokinins, ethylene) modulated by varying N availability (deficiency, sufficiency, excess) and chemical forms (NO₃⁻, NH₄⁺, organic N). Emphasis is placed on the systemic signaling pathways, including peptide-mediated long-distance communication (CEP—C-terminally encoded peptide receptor 1 (CEPR1)) and the critical role of the shoot in modulating root responses. Furthermore, we explore the emerging significance of carbon–nitrogen (C/N) balance, post-translational modifications (ubiquitination, phosphorylation), epigenetic regulation, and the complex interplay with other nutrients (phosphorus (P), sulfur (S)) and environmental factors in shaping N-dependent LR plasticity. Recent advances utilizing single-cell transcriptomics and advanced imaging reveal unprecedented cellular heterogeneity in LR responses to N. Understanding this sophisticated regulatory network is paramount for developing strategies to enhance nitrogen use efficiency (NUE) in crops. This synthesis underscores how N acts as a master regulator, dynamically rewiring developmental programs through molecular hubs that synchronize nutrient sensing with root morphogenesis—a key adaptive strategy for resource acquisition in heterogeneous soils. Full article

Nitrogen (N) is crucial for plant growth and stress resistance and is primarily absorbed and transported by nitrate transporters (NRT). Suaeda glauca, known for its strong salt-alkali stress resistance, and SgNRT genes have rarely been reported. This study aims to identify and analyze the SgNRT gene family to understand its composition, evolutionary patterns, and roles in salt stress responses. We identified 212 SgNRTs, which were categorized into three branches, with SgNRT1/SgNPF and SgNRT2 as the major families. Structural analysis, conserved domains, chromosomal localization, and collinearity were also examined. Spatiotemporal expression characteristics of SgNRT genes were analyzed, revealing specific expression across 13 organs or tissues and dynamic responses to salt treatment over 48 h. Notably, SgNRT1.185, SgNRT2.25, and SgNRT2.2 exhibited rapid salt induction in leaves (activated within 0.5 h, peaking at 2 h), with SgNRT1.185 showing relatively high upregulation. SgNRT1.185 and SgNRT2.35 were induced by high salt concentrations (200 mM) in both roots and leaves. SgNRT2.35 exhibited higher basal and stress-induced levels than the other genes. Bioinformatics analysis suggests spatially specific expression of SgNRT genes, potentially involved in nitrogen absorption and transport across various developmental stages and organs/tissues of Suaeda glauca. These findings offer a theoretical basis for understanding the adaptive strategies of Suaeda glauca under saline-alkali stress and provide insights into the functional evolution of plant NRT genes, aiding in the development of stress-resistant crops. Full article

The development of a new salt–alkaline-tolerant hybrid japonica rice is crucial for enhancing japonica rice supply and ensuring national food security. Utilizing molecular marker-assisted selection (MAS) technology combining Kompetitive Allele-Specific PCR (KASP) markers and a gene breeding chip, the salt-tolerant gene SKC1 was introgressed into a rice genotype Fan 14. This led to the development of Shenyanhui 1, a new high-quality, strongly heterotic, and salt-tolerant japonica restorer line. Subsequently, the high-quality, salt-tolerant japonica three-line hybrid rice variety Shenyanyou 1 was developed by crossing the BT-type japonica cytoplasmic male sterile (CMS) line Shen 21A with the restorer line Shenyanhui 1. Shenyanyou 1 carries the major salt tolerance gene SKC1, exhibiting excellent salt tolerance with seedling stage salt tolerance reaching level 5. Under precise salt tolerance evaluation throughout its growth cycle, Shenyanyou 1 achieved a yield of 3640.5 kg/hm², representing an extremely significant increase of 20.7% over the control variety Yandao 21. Shenyanyou 1 exhibits superior grain quality, meeting the Grade 3 high-quality rice standards issued by the Ministry of Agriculture. Shenyanyou 1 has good comprehensive resistance, aggregating rice blast resistance genes such as Pi2, Pita, Pizt and LHCB5, bacterial blight resistance genes Xa26/Xa3, stripe blast resistance gene STV11, semi-dwarf gene Sdt97, nitrogen-efficient utilization gene NRT1.1B, the light repair activity enhancement gene qUVR-10, the cold resistance gene qLTG3-1, and the iron tolerance gene OsFRO1. It has good resistance to biotic and abiotic stresses. This paper details the breeding process, key agronomic traits, salt tolerance, yield performance, and grain quality characteristics of Shenyanyou 1. Full article

Due to limited land resources and traditional farming practices, continuous cassava cropping is common in China. This practice leads to soil degradation, including reduced fertility, imbalanced microbial communities, and lower crop yields. In this study, we investigated the impacts of continuous cassava cropping (CC) and cassava–maize rotation (RC) systems on soil physicochemical properties, microbial community composition, and functional gene abundance related to carbon and nitrogen cycling. The RC system consists of a five-year rotation cycle: cassava is planted in the first year, followed by two consecutive years of maize, and then, cassava is planted again in the last two years. The soil type is classified as Haplic Acrisols with a clay loam texture in this research. Soil samples from both cropping systems were analyzed for physicochemical properties and enzyme activities, and the results showed significant decreases in soil pH, available nitrogen, available phosphorus, and available potassium in CC. Using metagenomic sequencing, 1,280,928 and 1,224,958 unigenes were identified under RC and CC, respectively, with differences in microbial taxonomic and functional profiles. Bacteria accounted for 89.257% of the soil community in RC, whereas the proportion was 88.72% in CC. The proportions of eukaryota and viruses in RC were 0.031% and 0.006%, respectively; in contrast, their proportions were 0.04% and 0.02% in CC, respectively. Cassava–maize rotation promoted the metabolic activities of soil microbes, leading to a significant enhancement in functional genes related to nitrogen and carbon cycling, such as nasA, nasD, nrtC, coxA, porA, and frdA. This shows that microbial activity and nutrient cycling improved in the crop rotation system. Thus, these findings highlight the importance of crop rotation for maintaining soil health, enhancing microbial functions, and improving sustainable cassava production. This study provides valuable insights into the management of cassava agroecosystems and the mitigation of the adverse effects of continuous cropping. Full article