Search Results (1,800)

Climate change is increasing flood frequency, exposing plants to severe stress. This study investigated the biostimulant-like effects of exogenous ferulic acid (FA; 1, 10, and 100 mg/L) on broccoli (Brassica oleracea var. cymosa) microgreens under regularly watered (RW) and flooded (F) conditions. Spectrophotometric, HPLC, and statistical analyses showed that all FA concentrations increased total phenolics and proanthocyanidins in flooded plants, while only 100 mg/L increased proanthocyanidins in RW plants. FA at 1 and 100 mg/L reduced soluble sugars in RW broccoli (18% reduction by both FA concentrations) and enhanced antioxidant capacity (measured by ferric reducing antioxidant power assay, FRAP) in flooded plants (8% and 11%, respectively). Only 10 mg/L FA lowered hydrogen peroxide in RW plants. Flooding significantly decreased glutathione (GSH) levels, but FA treatment doubled GSH concentration and restored its level in flooded broccoli, improving redox balance. FA also influenced individual polyphenols more strongly in RW plants, with notable increases in sinapic acid and kaempferol. Overall, FA enhanced antioxidant status and redox homeostasis under flooding stress, mainly by stimulating glutathione accumulation and phenylpropanoid metabolism. Its regulatory effects were strongly dependent on soil water conditions. These findings underscore the practical and agronomic potential of FA as an effective approach to enhance crop resilience under climate change. Full article

Subterranean termites, particularly Odontotermes obesus, cause severe damage to forest nurseries and plantations in arid and semi-arid ecosystems. This study demonstrates the dual functional role of endophytic entomopathogenic fungi, Metarhizium anisopliae and Beauveria bassiana, in termite suppression and induction of plant defense responses. Laboratory bioassays revealed significantly higher virulence of M. anisopliae, with a lower LT₅₀ (lethal time required to cause 50% mortality) of 33.1 h compared to B. bassiana (46.7 h), a steeper probit slope (5.4 ± 0.3), and strong model fit (R² = 0.95), indicating rapid and synchronized mortality. Endophytic colonization varied across host species and application methods, with soil incorporation consistently outperforming foliar inoculation. Maximum colonization (82.5%) was recorded in Tecomella undulata and exceeded 80% in Azadirachta indica under M. anisopliae. Biochemical analyses revealed significant increases in protein (up to 3.5 mg g⁻¹), phenols (3.7 mg g⁻¹), and tannins (2.7 mg g⁻¹). Activity of defense enzymes was significantly enhanced, with catalase reaching 263.5 U mL⁻¹, while Phenylalanine ammonia-lyase and Tyrosine ammonia-lyase exceeded 170 and 198 U mL⁻¹, respectively, indicating activation of antioxidant and phenylpropanoid pathways. Molecular docking analysis further revealed strong interactions between fungal metabolites and termite cellulase, with Bassianin (−8.4 kcal mol⁻¹) and Tenellin (−8.1 kcal mol⁻¹) showing the highest binding affinities. These findings highlight the combined biochemical and molecular mechanisms underlying fungal-mediated termite suppression and plant defense induction, and future research should prioritize transcriptomic validation, rhizosphere microbiome interactions, formulation optimization, and long-term multi-location field evaluation to support sustainable termite management strategies. Full article

Low temperatures severely restrict tea plant (Camellia sinensis) growth and yield stability, yet how brassinosteroid (BR) signaling modulates cold acclimation at a systems level remains insufficiently defined. Here, we integrated transcriptomic and UHPLC–MS metabolomic profiling of tea leaves under Control, 24-epibrassinolide (EBR), Cold, and Cold + EBR treatments to delineate BR-potentiated cold responses. Principal component analyses revealed clear treatment-specific separation and tight clustering of biological replicates at both omics levels. Quantitatively, cold stress induced extensive reprogramming (4075 differentially expressed genes (DEGs) and 298 differentially accumulated metabolites (DAMs)), whereas EBR alone exerted relatively modest effects (231 DEGs and 50 DAMs). Notably, EBR under cold conditions further reshaped cold-responsive networks (371 BR-modulated DEGs and 17 BR-modulated DAMs), consistent with a potentiating role for BR signaling. Functional enrichment analyses highlighted phenylpropanoid metabolism and hormone signal transduction as core responsive modules, with coordinated activation of key gateway genes (PAL, C4H, and 4CL) and concurrent engagement of lignin-, flavonoid-, and catechin-associated branches under Cold + EBR. Metabolomic analyses identified flavonoids as the dominant responsive metabolite class (49.31%), particularly anthocyanins and flavonol glycosides. Integrative TF–metabolite–gene correlation networks prioritized WRKY transcription factors (TEA001162, TEA027058) and a UDP-glycosyltransferase gene (TEA025792) as candidate hub genes linking hormone signaling to phenylpropanoid outputs. Collectively, this work provides a systems-level framework of co-regulated transcript–metabolite modules and candidate molecular targets, offering a foundation for functional validation and practical improvement of cold resilience in tea production. Full article

The deep physiological dormancy of Zanthoxylum armatum DC. seeds severely limits its seedling propagation efficiency. Variable temperature stratification is an effective treatment for promoting dormancy release; however, the metabolic basis underlying this process remains poorly understood. In this study, we utilized a UPLC-MS/MS-based untargeted metabolomics approach, coupled with multivariate statistical analyses (PCA and OPLS-DA), to profile metabolic changes in Z. armatum seeds subjected to variable temperature stratification in a moist sand substrate (15 °C in the dark for 10 days, followed by 4 °C for 20 days). A total of 3687 metabolic features were detected, among which 33 structurally annotated differential metabolites were retained for biological interpretation, including 8 upregulated and 25 downregulated metabolites. Pathway enrichment analysis indicated that α-linolenic acid metabolism and linoleic acid metabolism were markedly altered after stratification. In particular, 9-(S)-HPOTE, colneleate, jasmonic acid (JA), and JA-ACC were significantly reduced, suggesting that attenuation of JA-related oxylipin metabolism may be associated with dormancy release in Z. armatum seeds. In addition, coordinated changes in phenylpropanoid- and cutin/wax-related metabolites implied remodeling of seed-coat-associated metabolism, whereas the accumulation of branched-chain amino acids and the alteration of sulfur- and purine-related metabolites suggested reorganization of metabolic reserves during the transition from dormancy to germination. Overall, these results provide metabolomic evidence that variable temperature stratification is associated with extensive metabolic reprogramming in Z. armatum seeds and highlight JA-related lipid metabolism as a candidate pathway involved in dormancy release. Full article

Drought stress is one of the most critical abiotic stresses restricting global crop production, and sorghum plays an important role in arid and semi-arid areas due to its inherent drought tolerance compared to many other cereals. However, significant variation in drought tolerance exists among different sorghum genotypes, which provides an opportunity to dissect the underlying mechanisms. In this study, a drought-tolerant sorghum line (LNR-6) and a drought-sensitive line (LR-2381) were used for comparative analysis. Plants were grown under two water regimes: well-watered conditions (CK, soil water content maintained at 40%) and drought stress (soil water content reduced to 24%). Integrated transcriptomic and non-targeted metabolomic analyses were conducted to investigate the physiological and molecular mechanisms underlying sorghum drought tolerance. Phenotypic analysis showed that drought stress significantly reduced plant height and chlorophyll content in the drought-sensitive genotype, whereas the drought-tolerant genotype showed only minor changes. Transcriptome analysis identified several enriched functional categories of differentially expressed genes between the two genotypes under drought stress. Among them, genes associated with limonene and pinene degradation, photosynthesis, and photosynthesis-antenna proteins were significantly enriched and may be involved in drought-response regulation. Metabolomic analysis revealed significant accumulation of flavonoids and phenylpropanoids under drought conditions. KEGG pathway enrichment further indicated that flavone and flavonol biosynthesis, flavonoid biosynthesis, and phenylpropanoid biosynthesis were the most significantly enriched metabolic pathways. Overall, these findings enhance our understanding of the coordinated transcriptional and metabolic responses underlying drought tolerance in sorghum. Full article

Chimonobambusa utilis is a dominant bamboo species in China, yet its leaves remain an underutilized resource despite their significant bioactive potential. To elucidate the metabolic reprogramming of Ch. utilis leaves across an elevational gradient and its link to antioxidant phenotypes, we integrated widely targeted metabolomics with redox profiling of leaves collected from 1150, 1600, and 2000 m in the Qingba Mountains. The mid-elevation (1600 m) group exhibited the most robust antioxidant capacity and the highest total flavonoid content. Metabolomic analysis identified 3113 metabolites across 13 classes, with flavonoids (604 compounds, 22.7% of total abundance) emerging as the predominant secondary metabolites. Pairwise comparisons revealed 1716 differentially accumulated metabolites (DAMs). KEGG enrichment indicated that while the low-elevation (1150 m) group prioritized primary metabolism and upstream phenylpropanoid branches, the high-elevation (2000 m) group was associated with photoprotection and defense responses. In contrast, the mid-elevation environment optimized the flux toward flavonoid biosynthesis while maintaining steady metabolic supply. HPLC quantification further confirmed that key markers—vitexin, hyperoside, orientin, and luteoloside—peaked at 1600 m. Correlation analysis between 423 differential flavonoids and antioxidant indices demonstrated that distinct radical-scavenging activities are driven by specific flavonoid structural motifs. Overall, altitude-driven metabolic remodeling, characterized by a mid-elevation advantage for flavonoid accumulation, dictates the antioxidant plasticity of Ch. utilis leaves. Full article

Acibenzolar-S-methyl (ASM), a salicylic acid (SA) analog, and jasmonic acid (JA) are chemical inducers of plant defenses, yet crosstalk between SA- and JA-associated pathways may result in antagonistic outcomes. Here, we assessed how ASM and JA, applied alone or in combination, are associated with rice blast severity and defense-related responses in an upland rice cultivar. Plants of rice (Oryza sativa L., cv. Primavera) were treated with JA, ASM or JA + ASM and subsequently challenged with Magnaporthe oryzae. ASM treatment was associated with reduced leaf blast severity (LBS), whereas JA treatment was associated with increased LBS. Antagonistic outcomes were observed in the combined treatment: LBS in JA + ASM plants was higher than in ASM-treated plants but lower than in JA-treated plants. Lipoxygenase (LOX) activity was induced by JA and positively correlated with LBS, indicating that higher LOX activity aligned with greater susceptibility under the tested conditions. In contrast, ASM-treated plants showed higher peroxidase (POX) activity, which was associated with lower LBS. Disease outcomes were also linked to secondary defense metabolism and phenylpropanoid-related components, including phenylalanine ammonia-lyase (PAL), salicylic acid (SA) and phenolic compounds (PC). Overall, these results provide an integrated biochemical profile of how ASM, JA and their combination are associated with contrasting blast outcomes in upland rice, consistent with antagonistic interactions between JA- and SA-associated defense responses. These findings may inform the use of defense inducers and the interpretation of defense markers in upland rice systems where blast management is a major constraint. Full article

Background/Objectives: Dendrobium officinale (D. officinale), an endangered ornamental and medicinal orchid, displays significant variability in its bioactive compounds depending on geographical and environmental factors. To decipher these influences, we investigated metabolic divergence across three cultivars (GN, LS, DX) cultivated in greenhouse and outdoor conditions using untargeted metabolomics. Methods: Metabolites extracted from stem and leaf tissues were analyzed via UHPLC-Q Exactive Orbitrap MS, and the raw data were processed using XCMS for peak alignment and quantification. Differentially abundant metabolites (DAMs) were identified by multivariate statistical analyses including PCA and OPLS-DA. Metabolic pathways were annotated using KEGG, HMDB, and LIPID Maps databases, with enrichment analysis and visualization performed via TBtools II and Hiplot. Results: Metabolite profiling and multivariate analysis revealed distinct chemotypes. The DX cultivar exhibited anthocyanin enrichment in its stems, correlating with a red pigmentation, while GN accumulated specific amino acid derivatives. Tissue-specific metabolic specialization was evident, with leaves displaying greater flavonoid diversity and stems prioritizing lipid and amino acid metabolism. Outdoor cultivation enhanced flavonoid biosynthesis, whereas greenhouse conditions favored alkaloid accumulation. Functional analysis identified both conserved pathways, like phenylpropanoid biosynthesis, and varietal-specific adaptations in amino acid and secondary metabolism. Notably, alkaloid levels declined sharply during plant defoliation. Conclusions: Our findings demonstrate that environmental factors and geographical origin synergistically shape the metabolic profiles of D. officinale. This provides a scientific basis for optimizing cultivation strategies—through targeted environmental adjustments and varietal selection—to enhance the yield of desired bioactive compounds. Full article

Cadmium (Cd) contamination is widely recognized as a major risk factor affecting the security and quality of crop production. Watermelon (Citrullus lanatus) is a globally cultivated fruit that is susceptible to Cd stress. 24-Epibrassinolide (EBR), an active brassinosteroid, is essential for plant growth and abiotic stress responses. However, its protective role in watermelon under Cd stress remains unclear. This study elucidates the physiological and molecular processes underlying EBR-mediated alleviation of Cd toxicity in watermelon seedlings. The results showed that exogenous EBR application effectively mitigated Cd-induced growth inhibition through decreased Cd deposition, reduced the accumulation of reactive oxygen species (ROS), lowered membrane lipid peroxidation, and increased antioxidant capacity in watermelon leaves under Cd treatment. Transcriptome (RNA-Seq) analysis revealed that EBR triggered substantial reprogramming of gene expression patterns, identifying 530 differentially expressed genes (DEGs) in Cd + EBR co-treatment compared with Cd treatment alone, including 204 down-regulated genes and 326 up-regulated genes. These DEGs are vital for controlling several physiological processes, including phenylpropane metabolism, phenylpropanoid biosynthesis, endoplasmic reticulum’s protein production, cell wall organization, and others. Further physiological assays confirmed that EBR increased the activities of PAL and 4CL, the core enzymes driving phenylpropanoid biosynthesis, leading to a significant accumulation of total phenols and flavonoids. Together, the above results give concrete proof of the powerful functions of 24-EBR, acting as an enhancer of plant performance under Cd stress by enhancing the antioxidant system and by activating the phenylpropanoid pathway and its derived metabolic networks. Full article

Citrus genomes as storehouses of genetic information of immense commercial utility remain untapped for the improvement of fruit quality traits and other production-related stresses. With the rapid expansion of transcriptomic datasets, integrative meta-analysis has further aided in uncovering interspecies molecular mechanisms associated with fruit quality development. In this study, we performed a cross-project RNA-Seq meta-analysis, integrating multiple publicly available BioProjects encompassing diverse citrus species, viz., Citrus sinensis, C. reticulata, C. maxima, C. clementina, C. japonica, and C. papeda, known to dominate the morphogenetic evolution of the citrus industry. High-throughput RNA-Seq data were processed using various bioinformatics tools. A total of 15 interspecies comparisons identified 676 unique DEGs, enriched in pathways related to secondary juice yield and processing quality traits. We also established that domestication aided in metabolism, oxidative stress responses, phenylpropanoid and flavonoid biosynthesis, and hormone-mediated signaling. Multivariate analyses (PCA and heatmap visualization) highlighted distinct yet overlapping expression patterns across these citrus species. By combining differential expression, co-expression network analysis and QTL-GWAS integration, we identified 19 high-confidence candidate genes responsible for transcriptomic variation associated with measurable fruit quality traits. Genes such as LOC102612823 and LOC102607495, which co-localized with seed number QTLs on chromosome 1, represented strong candidates regulating reproductive development and seed formation, the traits that directly influence fruit texture and market acceptability. Genes linked to juice content QTLs, including LOC102611137 and LOC102612553 on chromosome 5, suggested their roles in metabolic regulations behind juice accumulation. These loci provided definitive breeding clues for enhancing the reshaping of citrus fruit transcriptomes while retaining key ancestral regulatory components. Full article

Soybean (Glycine max L.) is an important agricultural crop for human food and animal feed. Soybean yield is severely constrained by abiotic stresses such as salinity and drought, which affect large proportions of arable and irrigated lands worldwide. This necessitates the development of new soybean varieties tolerant to these stress factors. Mutation breeding is an effective approach to improve the stress tolerance of plants due to increased genetic diversity. In this study, two gamma-induced salinity and drought-tolerant soybean mutants (SM1 and SM3-1) were compared with the parental line S04-05 using GO and KEGG pathway enrichment analyses. GO enrichment analyses revealed extensive differential gene expression in the mutant lines under stress conditions, with significant enrichment of pathways related to photosynthesis, hormone signaling, carbohydrate metabolism, and flavonoid and isoflavonoid biosynthesis. Genotype-specific analyses indicated that the SM3-1 mutant exhibited a dynamic regulatory response associated with maintaining the photosynthetic apparatus and chloroplast homeostasis under stress, whereas the SM1 mutant showed an adaptation strategy based on metabolite-mediated osmotic adjustment and ROS scavenging. Compared to the parental variety S04-05, the mutants showed distinct metabolic regulation in phenylpropanoid/isoflavone metabolism, with upregulation of many isoflavone biosynthesis genes under salinity, drought, and untreated conditions, indicating a key and sustained role of this pathway in stress tolerance. Most SNPs identified in the isoflavone biosynthesis pathway consist of moderate-impact and modifier variations. These findings suggest that gamma mutagenesis and subsequent selection processes allow for the development of novel genetic variants that operate through different physiological and metabolic mechanisms but exhibit similar levels of tolerance. In this respect, the study reveals that mutation breeding is a potentially sustainable and effective breeding strategy for increasing abiotic stress tolerance in soybeans. Full article

Abscisic acid (ABA) regulates diverse aspects of plant growth and secondary metabolism, yet its concentration-dependent effects on rhizomatous spice crops remain poorly understood at the systems level. Here, we investigated the phenotypic, physiological, hormonal, and multi-omics responses of ginger (Zingiber officinale) to foliar-applied ABA across a concentration gradient. Exogenous ABA modulated ginger growth in a distinctly non-linear manner. Low-to-moderate concentrations (5–15 mg/L) significantly enhanced aboveground branching and belowground rhizome yield, whereas high concentration (35 mg/L) inhibited branching while promoting structural carbohydrate accumulation, revealing a concentration-dependent trade-off between growth and secondary wall deposition. Hormone profiling uncovered global reprogramming of the endogenous hormonal network, with optimal ABA (15 mg/L) coordinately elevating growth-promoting hormones and defense-related signals, while high concentrations suppressed multiple hormone pathways and triggered negative feedback inhibition of endogenous ABA biosynthesis. Integrated metabolomic and transcriptomic analyses identified convergent enrichment on phenylpropanoid biosynthesis, gingerol biosynthesis, and plant hormone signal transduction. Co-expression network analysis revealed a highly interconnected module of 583 genes linking hormone signaling to secondary metabolism, with coordinated up-regulation of key enzymes from phenylalanine ammonia-lyase (PAL) to polyketide synthase under 15 mg/L ABA explaining the 64% increase in 6-gingerol content. This study establishes a mechanistic chain from ABA perception to improved ginger yield and quality, mediated by hormonal crosstalk and transcriptional activation of the phenylpropanoid-gingerol network. We propose an “ABA optimization window” of 5–15 mg/L for precision cultivation of high-quality ginger, providing a systems-level framework for understanding hormone-mediated regulation of secondary metabolism in medicinal and spice crops. Full article

Background/Objectives: Proso millet (Panicum miliaceum L.), a drought-tolerant cereal vital to semi-arid agriculture, faces severe yield losses from head smut disease caused by the pathogen Sporisorium destruens. Although partial resistance exists, the dynamic molecular mechanisms governing its defense response across developmental stages remain poorly understood. Methods: Here, we performed untargeted metabolomics on leaf samples from Inoculated Asymptomatic (IA) and Inoculated Symptomatic (IS) plants of the partially resistant cultivar ‘Chishu 13’ at four key growth stages following pathogen inoculation, with group classification validated by qPCR. Using weighted metabolite co-expression network analysis (WGCNA) combined with differential metabolite screening, we identified 18 metabolites markedly enriched in the tricarboxylic acid (TCA) cycle, metabolite transport-related processes, and phenylpropanoid biosynthesis pathways. Results: Notably, L-phenylalanine accumulated substantially in IA plants relative to IS plants and correlated closely with biosynthesis of key defensive phenylpropanoids, including cinnamic acid and p-coumaric acid. Our results reveal distinct temporal patterns in metabolic reprogramming that correlate with resistance outcomes in Inoculated Asymptomatic plants: early stages are characterized by differential regulation of energy metabolism, while later stages show enhanced phenylpropanoid biosynthesis. These stage-specific metabolic adaptations are strongly associated with successful defense outcomes. Conclusions: These findings elucidate stage-specific metabolic adaptations that distinguish successful defense in IA plants from susceptibility in IS plants, providing robust biomarkers and stage-targeted strategies for breeding smut-resistant millet varieties. Full article

Phenolic compounds contribute to the color, flavor, and functionality of foods but are often degraded during conventional heat treatments, prompting interest in non-thermal techniques. Thermal methods produce heat-driven changes that are more directly interpretable, whereas non-thermal methods require compound-resolved interpretation because higher post-treatment signals may reflect release from bound pools rather than true preservation. This review evaluates liquid chromatography–mass spectrometry (LC–MS) evidence on how ultrasound, high-pressure processing, pulsed electric fields, and cold plasma reshape polyphenol fingerprints across food matrices (2021–early 2026). Ultrasound and high-pressure processing preserve constitutive structures while increasing measurable phenolics through cell disruption and bound-pool release. Pulsed electric fields show similar release behavior but may shift toward oxidative losses when electroporation increases enzyme contact or downstream operations amplify degradation. Cold plasma introduces reactive oxygen and nitrogen species, with the clearest LC–MS/MS evidence for oxidation and nitration. In fresh-cut tissues, stress responses elevate phenylpropanoid products. Bulk assays such as total phenolic content (TPC) cannot separate preservation from release or true chemical conversion alone. LC–MS offers the compound-level detail needed to understand how each non-thermal technique changes polyphenol structure and functionality across food matrices. Full article

Dictyophora rubrovolvata is highly regarded and increasingly cultivated in China for its nutritional value, unique taste, and medicinal properties. However, the chemical composition of fresh D. rubrovolvata is unclear. This study applied a comprehensive metabolomic analysis of D. rubrovolvata to characterize and compare the metabolite profiles and identify significantly differential metabolites from three geographical origins in China. Ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS/MS) combined with chemometrics was employed to conduct untargeted metabolomics analysis of fresh D. rubrovolvata samples collected from the Sichuan, Fujian, and Guizhou provinces in China. Among the 383 identified metabolites, lipids and organic acids were the predominant classes. There were notable variations in metabolite composition across the three geographical areas. The Sichuan (SC) group showed a high concentration of phospholipids, the Guizhou (GZ) group was characterized by specific oxidized lipids and bioactive benzenoids, and the Fujian (FJ) group showed elevated levels of the antioxidant ergothioneine. We identified 17 unique metabolites, including tryptophol, 12-oxophytodienoic acid, and various fatty acid derivatives, which may act as significantly differential metabolites for different origins. Analysis of KEGG enrichment indicated that the main metabolic pathways involved were tryptophan metabolism, glycerophospholipid metabolism, and phenylpropanoid biosynthesis. Full article