Search Results (23,007)

Non-invasive, real-time monitoring of plant water status is critical for precision agriculture and plant physiology. However, existing methods often lack continuous in situ measurement capability or are limited by temporal resolution. This paper proposes a novel non-invasive method based on xylem electrical conductivity, inspired by industrial non-contact fluid measurement. As a ground-based complement to remote sensing, this approach demonstrates the feasibility of online, in situ, and non-invasive monitoring of water stress in grapevine stems under controlled laboratory conditions. The industrial C⁴D sensing system is adaptively modified into a specialized Plant-C⁴D sensor with an array-based design for batch signal acquisition. To validate the electrical response to water loss, a gravimetric natural dehydration experiment was conducted, demonstrating a clear correlation between electrical signals and water content changes in detached stem samples. Full-day dynamic experiments are conducted under three conditions: normal water supply, varying water stress, and plant inactivation. Sensitive characteristic parameters are extracted through signal analysis, and a pattern recognition framework is established to eliminate environmental interference and suppress individual differences. Experimental results on 24 plant samples (Shine Muscat) show that the method accurately discriminates viable from inactivated plants with an accuracy of 91.67% (22/24 correct). Furthermore, the Fuzzy C-Means (FCM) clustering algorithm successfully quantifies the severity of water stress in viable plants, yielding results consistent with actual water supply conditions. While these findings demonstrate the capability of Plant-C⁴D sensor to capture stem water status-related information, the current results do not establish full physiological validation, warranting further exploration with in vivo experiments. Full article

Benzylisoquinoline alkaloids (BIAs) are significant defensive and pharmaceutical metabolites found in medicinal plants of the Papaveraceae family. Among these, dehydrocavidine is a distinctive bioactive constituent of Corydalis saxicola Bunting, an endangered medicinal plant endemic to karst habitats, known for its definite hepatoprotective, anti-inflammatory, and antiviral pharmacological properties. Berberine bridge enzyme-like (BBEL) proteins serve as key rate-limiting enzymes catalyzing core skeletal oxidation in BIA biosynthesis. However, their functions in C. saxicola remain uncharacterized. In this study, we performed a comprehensive functional genomic analysis of the BBEL family in C. saxicola (CsBBELs). A total of 22 CsBBEL members were identified from the genome of C. saxicola, all of which possess the conserved FAD-binding domain and BBE functional domain characteristic of the BBEL family. Phylogenetic analysis revealed that the CsBBEL family formed three clades closely clustered with homologs from related Papaveraceae species, indicating high conservation. Expression profiles demonstrated significant organ specificity and Ca²⁺ stress response of the CsBBEL genes, with CsBBEL3, CsBBEL16, and CsBBEL17 being particularly highly expressed in roots. Protein structure prediction and molecular docking suggested that these candidates bind cavidine and tetrahydrocolumbamine. In vitro enzymatic assays confirmed that CsBBEL3/16/17 specifically catalyzed the four-electron oxidation of cavidine and tetrahydrocolumbamine to produce dehydrocavidine and columbamine, respectively, exhibiting oxidase activity in the BIA biosynthetic pathway. These findings not only contribute to germplasm conservation but also lay a foundation for the synthetic biology-based improvement of C. saxicola. Full article

Protein hydrolysates (PHs) have emerged as a pivotal category of plant biostimulants in sustainable agriculture. They are derived from the enzymatic, chemical, or thermal hydrolysis of agro-industrial by-products of animal or plant origin. These complex mixtures of free amino acids, oligopeptides, and polypeptides enhance crop productivity, nutrient use efficiency, and abiotic stress resilience. This review examines and compares the production methods, chemical composition, agronomic performance, physiological mechanism, and safety profiles of animal-derived (A-PHs) and vegetal-derived (V-PHs) protein hydrolysates, with particular emphasis on hydrolyzed collagen (HC) as an emerging biostimulant. Furthermore, the specific physiological roles of proline in mediating plant stress tolerance and hydroxyproline-rich glycoproteins in maintaining cell wall integrity are evaluated. Animal-derived sources, including collagen, keratin, and fish by-products, are characterized by elevated glycine, proline, and hydroxyproline concentrations, amino acids with established roles in root architecture promotion, reactive oxygen species (ROS) scavenging, and osmotic adjustment under stress. Conversely, V-PH exhibit richer bioactive peptide profiles and superior environmental sustainability indices. Underlying mechanisms encompass hormone-like activities mimicking auxin and gibberellin signaling, transcriptional reprogramming of nitrogen assimilation pathways, antioxidant enzyme modulation, and rhizosphere microbiota stimulation. Full article

Sclareol, a natural diterpene, exhibits diverse physiological activities in plants, microorganisms, and animals. Exogenous application of sclareol to Arabidopsis thaliana leaves induces chlorosis-like symptoms accompanied by a reduction in chlorophyll content. In our previous study, a bioassay-guided fractionation approach was employed to isolate endogenous compounds responsible for this decrease, leading to the identification of campesterol and stigmasterol as active phytosterols. Notably, this approach also indicated the presence of additional active substances in fractions lacking these phytosterols. In the present study, we identified α-pinene, oleic acid, triolein, and pipecolic acid as additional compounds capable of reducing chlorophyll content. Exogenous application of each compound to Arabidopsis leaves resulted in a dose-dependent decline in chlorophyll levels. Furthermore, sclareol treatment increased the endogenous accumulation of these metabolites, along with the expression of genes involved in their biosynthesis. Because phytosterols, terpenoids, lipids, and pipecolic acid have been implicated in plant growth and development, stress responses, and disease resistance, the metabolites identified in this study are likely to contribute not only to sclareol-induced chlorophyll reduction but also to other physiological responses elicited by sclareol. Collectively, these findings suggest that sclareol triggers coordinated metabolic reprogramming in Arabidopsis, leading to the accumulation of multiple bioactive metabolites that mediate diverse physiological processes. Full article

Urtica dioica L. (stinging nettle) is a perennial herb with a long ethnomedicinal history and diverse pharmacological potential. This comprehensive review consolidates current knowledge on its phytochemistry, extraction technologies, bioactivities, and molecular mechanisms. However, recent reviews have generally addressed these aspects separately, and an integrated assessment linking green extraction technologies and phytochemical profiles to molecular mechanisms and gene expression modulation is still lacking. U. dioica contains abundant polyphenols (rutin, quercetin, kaempferol, and chlorogenic acid), sterols (β-sitosterol and stigmasterol), vitamins, carotenoids, and the antiviral lectin Urtica dioica agglutinin (UDA). Advances in green extraction technologies, such as ultrasound-assisted extraction, microwave-assisted extraction (MAE), pressurized liquid extraction, and natural deep eutectic solvent (NADES)-based systems, have significantly improved yield, purity, and environmental sustainability compared to conventional maceration and Soxhlet methods. Comprehensive chromatographic and spectroscopic profiling (HPLC, GC–MS, FTIR, NMR, and LC–MS/MS) has established detailed chemical fingerprints linking bioactive constituents to antioxidant, anti-inflammatory, antimicrobial, and antiviral properties. Mechanistic studies reveal that U. dioica exerts its therapeutic effects through modulation of oxidative stress, inhibition of the NF-κB and COX-2 pathways, enhancement of endogenous antioxidant enzymes, and regulation of apoptotic gene expression. Moreover, NADES–MAE extracts demonstrate potential as sustainable, high-efficacy formulations for nutraceutical and cosmetic applications. Despite extensive preclinical evidence, clinical standardization and dosage optimization remain major challenges. This review underscores U. dioica as a multifunctional medicinal plant with significant promise for next-generation phytotherapeutics and molecular nutrition. Full article

Rice is highly vulnerable to concurrent drought-heat stress, which intensifies the disruption of plant growth and can cause high seedling mortality. Limited genetic diversity further constrains breeding for combined stress adaptation. Thus, mutation breeding has emerged as a solution for inducing beneficial variability in rice genomes. Based on this solution, this study aimed to identify rice mutants tolerant to drought and heat through artificial screening combined with multi-trait index analysis. Experiments were conducted from April to August 2025 at Hasanuddin University in two sequential phases: seedling screening in a controlled stress chamber and pot evaluation under semi-controlled conditions. Mutants were derived from the seeds of the double haploid (DH) rice line HS1-28-1-5, which was previously developed through anther culture and exhibited potential abiotic stress adaptability. DH seeds were exposed to gamma irradiation (200–1000 Gy) as the M1 population. Based on radiosensitivity evaluation, 200 and 400 Gy were selected and used in the present study as the M2 populations. Rice M2 evaluation results indicated that 200 Gy irradiation enhanced phenotypic variability with improved performance, whereas M2 400 Gy resulted in broader but less stable variation. Yield components were strongly associated with weight per clump, with panicle length being the primary direct contributor and weight per panicle mediating indirect effects. Principal component analysis accounted for 89.13% of the total variation, which was predominantly driven by yield traits. Integrated weighted average absolute score–tolerance score analysis classified genotypes into tolerance groups, identifying 33 putative tolerant mutants, with M2 200 Gy mutants demonstrating superior adaptability to drought-heat stress. These findings suggest that moderate irradiation coupled with multi-trait index selection provides a reproducible framework for identifying putative drought-heat-tolerant rice candidates at early stages while retaining relevance to subsequent yield recovery. Full article

Climate change and the increasing frequency of extreme temperatures pose severe threats to global agricultural productivity, making the breeding of water-efficient crops a critical imperative. Originating from arid regions, foxtail millet serves as an ideal C4 model crop for elucidating plant adaptations to water deficits. Unlike previous reviews that often isolate genomic features from physiological responses, this review constructs an explicit conceptual framework integrating cross-scale defense mechanisms—mechanistically linking molecular signal transduction and post-transcriptional regulation to cellular homeostasis and field-scale yield stability. We first detail the developmental stage-specific physiological penalties of water stress and dissect proactive water-conservation strategies, including stomatal anatomical optimization, root-carbon reallocation, and dynamic rhizosphere remodeling. At the genetic level, we highlight the application of dynamic quantitative trait loci (QTL) mapping, which transcends the static limitations of conventional QTLs by capturing the spatiotemporal evolution of drought-tolerance traits across distinct developmental nodes. To bridge the gap between intrinsic genetic potential and field application, we spotlight the emerging integration of machine learning-assisted breeding and genomic prediction for the efficient evaluation of superior germplasms. Across this framework, several persistent gaps emerge: most drought-responsive genes identified in foxtail millet remain at the level of expression association without functional validation; dynamic QTL analysis remains underutilized relative to its capacity to resolve reproductive-stage drought tolerance; and ML-based genomic prediction, though demonstrated in this species, has not been integrated into operational breeding. Closing these gaps will require connecting high-throughput field phenotyping to genomic selection and deploying functionally validated editing targets in genetic backgrounds relevant to dryland production. Full article

Alternating brackish–freshwater irrigation is a promising strategy for improving the utilization of marginal water resources in arid cotton (Gossypium hirsutum L.) production; however, its effectiveness is often limited by salt-induced physicochemical stresses, including sodium-induced soil structural degradation, osmotic stress, and reduced rhizosphere biological activity. This study investigated whether the combined application of microbial inoculant and polyacrylamide (PAM) could enhance root-zone functioning and plant performance under alternating brackish–freshwater irrigation. A controlled greenhouse pot experiment was conducted with five treatments, including conventional irrigation (CI), alternating irrigation (AI), AI combined with microbial inoculant (AI + B), AI combined with PAM (AI + PAM), and AI combined with microbial inoculant and PAM (AI + B + PAM). Soil water–salt conditions, physical properties, nutrient availability, microbial activity, root growth, and plant nutrient uptake were determined, and partial least squares path modeling (PLS-PM) was used to evaluate soil–root–plant interactions. Alternating irrigation reduced soil salinity and sodium accumulation compared with conventional irrigation, with electrical conductivity of the 1:5 soil–water extract (EC_1:5), Na⁺, and sodium adsorption ratio (SAR) decreasing by 14.68%, 16.21%, and 14.27%, respectively; under AI conditions, PAM increased water-stable aggregates by 22.54%, while microbial inoculant increased microbial biomass carbon by 33.47%. The combined AI + B + PAM treatment produced the greatest improvement in plant performance, increasing biomass, N uptake, P uptake, and K uptake by 28.79%, 47.37%, 48.00%, and 60.80%, respectively, compared with AI alone. PLS-PM supported a hypothesized pathway in which PAM-associated physical conditioning and microbial inoculant-mediated biochemical activation converged on root development, which was positively linked to nutrient acquisition and plant growth. These findings indicate that integrating microbial inoculant with PAM has potential to enhance root-zone resilience and cotton growth under alternating brackish–freshwater irrigation conditions, providing insights for the development of amendment strategies in saline soils. Further field validation is required before broader agricultural application. Full article

Hypertension is a major global health concern affecting over one billion people worldwide and is a leading risk factor for cardiovascular diseases, stroke, and kidney failure. Plant-derived bioactive compounds provide promising natural strategies for hypertension management by improving endothelial function, promoting vasorelaxation and diuresis, reducing oxidative stress, and modulating key molecular pathways. This review focuses on some important traditional medicinal plants from Northeast India with potential antihypertensive activity, summarizing their phytochemical constituents, pharmacological evidence, and proposed mechanisms of action. Northeast India lies within the Eastern Himalayas and Indo-Burma biodiversity hotspots and is recognized for its rich plant diversity. We conducted a systematic literature search using PubMed, Google Scholar, ScienceDirect, and Scopus following PRISMA guidelines. We further evaluated identified compounds for ADMET using open-source computational tools. Ten medicinal plants: Clerodendrum colebrookeanum, Moringa oleifera, Garcinia dulcis, Centella asiatica, Terminalia bellirica, Hibiscus sabdariffa, Citrus limon, Passiflora edulis, Garcinia cowa, and Solanum torvum yielded 22 bioactive compounds with notable antihypertensive activity. These compounds exhibited antioxidant, anti-inflammatory, and vasorelaxant effects via nitric oxide synthase activation, MAPK/NF-κB inhibition, ACE inhibition, calcium channel modulation, and reactive oxygen species scavenging. ADMET profiling indicated favorable pharmacokinetics, with vitexin, isovitexin, isoquercetin, and nobiletin showing low predicted toxicity and high stability. Full article

Heat stress severely hinders citrus yield and fruit quality. This study employed integrated physiological and transcriptomic analyses to investigate the effects of the exogenous application of abscisic acid (ABA) and brassinosteroid (BR) on heat stress responses in citrus. The results showed that the exogenous application of ABA and BR increased the contents of soluble sugar, proline, and ABA, and enhanced the activities of peroxidase and catalase under heat stress. Transcriptome trend analysis identified profiles 1, 6, and 7 as significantly enriched across exogenous ABA, BR, and control conditions. Profile 6 exhibited rapid upregulation followed by stabilization and showed a significantly higher gene count under both ABA and BR treatments than under the control. KEGG enrichment analysis revealed that genes in profile 6 were primarily enriched in amino sugar, nucleotide sugar, galactose, amino acids, 2-oxocarboxylic acid, glycerophospholipid, glucosinolate metabolism, MAPK signaling pathway, plant hormone signal transduction, protein processing in the endoplasmic reticulum, plant–pathogen interaction, and endocytosis. Furthermore, four genes encoding heat shock proteins (HSP), including HSP21A, HSP21B, HSP70-17, and HSP70A, were induced under heat stress and showed significant upregulation in response to exogenous ABA and BR treatments. In conclusion, these findings indicated that exogenous ABA and BR regulated ABA and osmoprotectant accumulation and antioxidant defense activation in response to heat stress. Full article

Drought stress is a major environmental factor limiting plant growth and distribution, with severe drought leading to plant mortality. This study investigates the physiological mechanisms underlying drought-induced mortality in one-year-old seedlings of the valuable timber tree species Phoebe bournei (Hemsl.) Yang, aiming to clarify the relative roles of hydraulic failure and carbon starvation. A 51-day controlled pot experiment was conducted to simulate progressive drought using 10 experimental groups (n = 6): a well-watered control and four drought treatment groups harvested at key physiological stages. Stage I (baseline) corresponded to a relative soil water content of approximately 89%. Stage II (photosynthetic cessation) was reached after approximately 15 days of water withholding, at a relative soil water content of approximately 60% and a predawn leaf water potential of approximately −3.4 MPa. Stage III (complete leaf wilting) was reached after approximately 36 days of water withholding. Stage IV (stem browning) occurred at a relative soil water content of approximately 18%, after approximately 45–51 days of water withholding. We systematically measured key physiological parameters, including leaf water potential, gas exchange parameters, the percentage loss of xylem conductivity in stems, and the concentrations of non-structural carbohydrates (including soluble sugars and starch) in different tissues. Results showed that stomatal conductance and net photosynthetic rate approached zero when leaf water potential fell to approximately −3.4 MPa. Stem percentage loss of xylem conductivity increased significantly with advancing drought, exceeding 75% at complete leaf wilting and reaching over 98% at stem browning, reflecting a near-complete loss of xylem hydraulic conductance. Concurrently, non-structural carbohydrate concentrations underwent transient accumulation during early drought, reflecting sink-limited carbon dynamics, followed by progressive depletion. Notably, partial non-structural carbohydrate reserves persisted even at the stem browning stage, suggesting that these reserves may have become physically inaccessible or metabolically unavailable rather than entirely exhausted. The findings point to a tightly coupled, sequential interaction between hydraulic failure and carbon starvation across the drought progression. The findings will provide a scientific basis for evaluating drought tolerance, informing adaptive management practices, and ensuring the sustainable cultivation of P. bournei under future climate scenarios. Full article

Plant regeneration demonstrates the remarkable developmental plasticity of plants, enabling tissue repair, organ formation, and adaptation to environmental challenges through cellular reprogramming and redifferentiation. This capacity underpins numerous horticultural and biotechnological applications, including grafting, micropropagation, somatic embryogenesis, organogenesis, and genetic transformation. While regeneration has traditionally been explained by the coordinated actions of auxin and cytokinin together with key developmental regulators such as WUSCHEL, BABY BOOM, and WUSCHEL-related homeobox genes, recent studies indicate that regeneration is also influenced by stress signaling, metabolic reprogramming, reactive oxygen species, and epigenetic regulation. Among these regulatory components, polyamines have emerged as important modulators of cell division, differentiation, stress responses, and morphogenic competence during in vitro regeneration. Likewise, autophagy, a conserved intracellular recycling pathway, has gained increasing attention for its role in maintaining cellular homeostasis, facilitating metabolic adaptation, and supporting developmental transitions under tissue culture conditions. This review summarizes current knowledge on the independent roles of polyamines and autophagy in plant cell reprogramming and in vitro regeneration, with particular emphasis on wound responses, somatic embryogenesis, and organogenesis. In addition, it highlights common physiological processes through which these pathways may influence regeneration and identifies the limited understanding of their potential relationship as an important direction for future research. Full article

Cr(VI) pollution severely damages plant cell wall structure and membrane integrity. Proline-rich proteins (PRPs), key cell wall structural components, rely on proline as their biosynthetic precursor. Pro accumulation has been shown to positively correlate with PRP abundance, suggesting a direct biochemical link between exogenous Pro [Pro_(exo)] application and PRP-mediated cell wall function. However, how Pro_(exo) regulates PRP expression to maintain cell wall structural integrity and membrane stability in rice seedlings under Cr(VI) stress remains unclear. In this study, the subcellular distribution of Cr, electrolyte leakage (EL), cell wall thickness, and the expression of PRP genes in rice seedlings were evaluated. The results revealed that Cr(VI) stress induced significant increases in EL and changes in cell wall thickness in rice seedling cells (p < 0.05). The application of Pro_(exo) significantly mitigated EL and increased cell wall thickness (p < 0.05). Furthermore, Pro_(exo) markedly increased the sequestration of Cr within the seedling root cell walls while reducing its distribution in the cytoplasm and organelles of seedling shoot cells (p < 0.05). Phylogenetic analysis of 48 OsPRP genes, on the basis of their homology with seven functionally characterized PRPs from other species, revealed 12 candidate genes in rice potentially involved in the regulation of cell membrane stability, cell wall assembly, thickening, and integrity. Subsequent qRT-PCR analysis and gene expression variation factor calculation revealed that Pro_(exo) significantly promoted the expression of OsPRP1.1, OsPRP3, OsRePRP2.1, OsHyPRP18, and OsHyPRP27 in roots and that of OsHyPRP27 in the shoots of rice seedlings under Cr(VI) stress. These findings indicate that Pro_(exo) enhances Cr compartmentalization within the root cell wall and improves membrane stability, thereby contributing to Cr(VI) tolerance in plants through the modulation of these key PRP genes. Our findings provide novel insights into the mechanism by which Pro_(exo) regulates PRP expression to affect plant cellular structural stability and heavy metal tolerance. Full article

Forage sorghum (Sorghum bicolor (L.) Moench) has excellent stress resistance and feeding quality. Lodging is one of the most critical factors influencing its yield and overall quality. However, there remains no definitive conclusion regarding the key indicators affecting the lodging of forage sorghum and their correlations. In this study, 149 forage sorghum lines, including 26 maintainer lines and 123 restorer lines, from the United States, China, and Japan were used to analyze the correlation between agronomic and mechanical properties at maturity. In addition, we selected forage sorghum with high, medium and low lignin content and observed the tissue sections, which further revealed the essence of lodging of forage sorghum from the microscopic point of view. Correlation analysis showed that lodging index (LI) was positively associated with plant height (PH), stem bending moment (SBM), lignin content (LC), stem center of gravity height (SGH), and fresh weight from the breaking point to the top of the panicle (FWP); lodging index was significantly negatively associated with breaking resistance (BR) and exhibited no significant correlation with stem diameter (SD) and lodging resistance of individual plant (LR). LI showed no significant association with BR and SD in the maintainer line subgroup, whereas LI was significantly negatively correlated only with BR and showed significant positive correlations with the other seven traits in the restorer line subgroup. Histological observation of the longitudinal section of the stem stained with Safranin O/Fast Green showed that the lodging resistance of sorghum could not be simply defined by the lignin content, and the structure of stem tissue played a more decisive role in determining the lodging resistance. Full article

Multiomics is increasingly valued as a strategy for investigating the regulatory mechanisms by which plants respond to adverse stress conditions. Currently, information on the molecular processes underlying plant responses to Pb stress, particularly those observed through an approach that combines proteomics and metabolomics, is lacking. Therefore, in this study, we aimed to explore functional correlations between Pb-responsive proteins and metabolites under Pb stress by performing label-free quantitative proteomics and untargeted metabolomics on the roots of the Pb hyperaccumulator Pogonatherum crinitum (Thunb.) Kunth. The selected Pb stress-responsive proteins were functionally verified using quantitative reverse transcription polymerase chain reaction (RT-qPCR) and parallel reaction monitoring (PRM). Under Pb stress, 397 upregulated and 431 downregulated proteins were identified through proteomic analysis. Metabolomic analysis identified 478 upregulated and 354 downregulated metabolites. Pathway enrichment analysis using the Kyoto Encyclopedia of Genes and Genomes revealed that differentially expressed proteins and metabolites were involved in pathways linked to heavy metal stress, such as starch and sucrose metabolism and plant hormone signal transduction. Through integrated proteomic and metabolomics analyses, we uncovered the coordinated regulatory interplay between glutathione (GSH) metabolism and jasmonic acid signaling. GSH reductase and 12-oxophytodienoate reductase drive the accumulation of GSH and jasmonic acid, respectively. The synergistic enhancement of these components is critical for maintaining cellular redox homeostasis and activating hormone-mediated defense signaling. These downstream metabolites were upregulated under Pb stress. RT-qPCR validation revealed that the transcriptional change trends were consistent with those of the proteomics analysis. Further quantitative validation of the target protein using PRM revealed significant upregulation under Pb stress. In conclusion, the P. crinitum root system upregulated the activity of key enzymes in the antioxidant system and plant hormone synthesis under Pb stress, thereby regulating the accumulation of GSH, glutamate, and metabolites for jasmonic acid synthesis. This integrated regulatory network provides promising candidate targets for breeding Pb-tolerant hyperaccumulators to remediate Pb-contaminated farmland and mining soil. Full article