Search Results (178)

Research on heterotrophic bioflocs is extensive, whereas investigations into autotrophic bioflocs remain limited. This study established an in situ autotrophic biofloc (ABF) system for intensive Pacific white shrimp (Penaeus vannamei) farming, aiming for zero water exchange and optimized water quality. A 120-day indoor experiment tested three stocking densities (300 (T1), 250 (T2), and 200 shrimp per m³ (T3)) with no water exchange. Water quality was monitored every two days, and bacterial communities were analyzed on days 10 and 70. The results indicated that ABF maturation was achieved by day 70 across all treatments, marked by three key indicators: (1) synchronous declines in nitrite and nitrate concentrations; (2) concurrent decreases in pH and total alkalinity approaching maturation; and (3) sustained high nitrogen removal efficiency (nitrite < 0.7 mg/L, ammonia < 0.6 mg/L). All density groups displayed similar patterns in both water quality dynamics and microbial community evolution. Bacterial analysis revealed that dominant genera such as Ruegeria, Bacillus, Muricauda, SM1A02, and Nitrospira played critical roles in toxic nitrogen removal, while pathogenic Klebsiella and Vibrio significantly decreased post-maturation. Heterotrophic nitrification and aerobic denitrification microorganisms (HNADMs) were identified as potentially responsible for nitrite accumulation. Nitrite accumulation was found in all groups. T2 and T3 achieved satisfactory breeding performance despite pre-maturation nitrate peaks exceeding 40 mg/L, whereas T1 suffered a low survival rate (27.47%) due to severe nitrite accumulation (>50 mg/L). A biofloc volume (BFV) of 4–8 mL/L effectively managed daily feed inputs of 75–110 g/m³. These findings lay a theoretical and technical foundation for the application of in situ ABF cultivation in intensive farming and enhance the sustainability of aquaculture. Full article

Cadmium (Cd) is a highly toxic heavy metal that severely impairs plant growth and poses ecological and health risks. Chrysanthemum indicum (L.), a dominant species in Cd-contaminated regions, represents a valuable germplasm for phytoremediation. In this study, we cloned and characterized CiWRKY50, a WRKY transcription factor containing a conserved WRKY domain and C2H2-type zinc finger. CiWRKY50 was localized to the nucleus but lacked intrinsic transcriptional activation activity. Overexpression of CiWRKY50 in Arabidopsis thaliana and C. indicum significantly enhanced Cd tolerance, as shown by reduced root Cd accumulation, improved transport efficiency, lower ROS and MDA levels, and increased chlorophyll, proline, and soluble protein contents. Antioxidant enzyme activities and Cd-chelating compounds (GSH, NPT, PCs) were also upregulated. Furthermore, combined Cd and ABA treatments promoted Cd sequestration in roots and activated ABA-responsive genes (CiABF1, CiABF2, CiABF4), alleviating shoot toxicity. These findings indicate that CiWRKY50 enhances Cd tolerance in association with enhanced ABA-mediated signaling and redox homeostasis, providing new insights for breeding Cd-resistant plants and improving phytoremediation strategies. Full article

The Xinjiang wheat variety ‘Xindong 22’ was used as experimental material. Two soil moisture treatments were established: control (CK, 70–75% field capacity), drought (X1, 60–65%). The photosynthetic characteristics and resistance physiological indexes of wheat leaves under different stress levels were analyzed, and RNA-Seq technology was used to conduct transcriptome sequencing and analysis were performed on wheat leaves. The results showed that under drought stress, superoxide dismutase (SOD) activity was significantly enhanced, while peroxidase (POD) activity decreased. Soluble sugar and proline contents also increased. These changes likely enhanced reactive oxygen species scavenging, thereby reducing the content of malondialdehyde in the leaves. Meanwhile, under the X1 treatment, stomatal conductance and transpiration rate of wheat leaves showed a slow decreasing trend, the intercellular CO₂ concentration decreased slightly, the decline in Fv/Fm was relatively small, and the value of the non-photochemical quenching coefficient gradually increased. Transcriptome analysis identified 1881 differentially expressed genes (DEGs). Notably, drought stress induced the up-regulation of key genes involved in the ABA signaling pathway (e.g., SnRK2 and ABF) and the MAPK cascade, suggesting their crucial roles in mediating drought responses in this wheat variety. In the jasmonic acid signaling pathway, MYC2 functions as a positive regulator by interacting with JAZ proteins. These findings demonstrate that Xinjiang wheat employs integrated physiological and molecular strategies to cope with drought stress. Full article

Soil salinization severely constrains the productivity of Medicago sativa L. Although exogenous melatonin (MT) has been proven to effectively alleviate salt stress injury in plants, the molecular regulatory networks underlying its function during the early stages of stress response remain not fully elucidated. In this study, we systematically investigated the specific regulatory mechanisms of exogenous MT-mediated salt tolerance in alfalfa seedlings during the early phase (12–24 h) of salt stress by integrating physiological, biochemical, and transcriptomic analyses. The results showed that MT treatment significantly inhibited membrane lipid peroxidation (indicated by decreased MDA content) in leaves and upregulated the activities of antioxidant enzymes as well as the levels of osmoprotectants, such as soluble sugars. Transcriptomic (RNA-seq) analysis revealed that MT induced a precise strategy of temporal transcriptional reconfiguration. At the initial stage of stress (12 h), MT preferentially downregulated the expression of genes related to ribosome biogenesis and chromatin remodeling. This transcriptional suppression suggests that plants adopted an “energy saving strategy,” aiming to minimize basal metabolic consumption and potentially reallocate limited energy resources toward the antioxidant defense system. Subsequently, at 24 h, MT orchestrated the comprehensive activation of the ABA signaling cascade and secondary metabolic pathways, such as phenylpropanoid and flavonoid biosynthesis, thereby establishing a long-term chemical defense barrier. Furthermore, weighted gene co-expression network analysis (WGCNA) identified ABF2 and Susy as key hub genes mediating soluble sugar accumulation. This study elucidates the molecular basis by which melatonin enhances early salt tolerance in alfalfa through a temporal transition from an “energy-saving” strategy to “active defense,” providing new theoretical insights for the molecular breeding of stress resistance in leguminous forage crops. Full article

Severe fluid loss in fractured, depleted reservoirs usually defeat conventional water-based drilling fluids (WBDFs), and rigid lost-circulation materials (LCMs) struggle to form durable, conformal seals. We report an eco-oriented colloidal gas aphron (CGA) fluid built from a nanostructured corn biopolymer (NCBP) and a biodegradable peanut-oil-derived surfactant, benchmarked against a reference fluid (RF) and aphron-only baselines (aphron based fluid, ABF). NCBP, produced by ball milling, was confirmed nanostructured by x-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), electron and atomic microscopies. Performance was evaluated from 25 to 90 °C for rheology, aphron stability and filtration at low temperature and low pressure (LTLP) of 100 psi and 25 °C, with post-test mud cake imaging. The optimized formulation, NCBP-2, showed stronger shear-thinning and higher gel strengths with heat, sustained stable and uniform aphrons for at least 120 min with foam persistence beyond 24 h, and delivered 3.0 mL filtrate with a 0.8 mm mud cake. These outcomes correspond to 60% less filtrate and approximately 73% thinner mud cakes than RF (7.5 mL; 3.0 mm), and about 14% and 33% improvements over the best ABF (3.5 mL; 1.2 mm). Micrographs revealed denser, finer-pored mud cakes, consistent with a mechanism in which deformable aphrons bridge micro-fractures while nano-scale polymeric fillers tighten the mud cake network. The results demonstrate decisive loss-control gains with temperature-tolerant rheology, supporting bio-based CGA fluids for depleted and fractured formations. Full article

Preventing spoilage in food products, particularly in those highly susceptible to rapid deterioration like mutton, has been a persistent challenge in the food industry. In this study, an Active Biological Film (ABF) was developed using chitosan (CS) and whey protein isolate (WPI), with the addition of 0.01 wt% titanium dioxide (TiO₂) and 0.1 wt% white pepper essential oil (WPEO). This ABF was applied to preserve fresh mutton at super-chilling temperatures of −1.7 ± 0.2 °C. The effects of ABF on myofibrillar protein (MP) oxidation and structural characteristics, as well as on the microbial status, physicochemical properties, and sensory quality of mutton, were systematically evaluated. The results demonstrated that, compared to the control group (CK), ABF treatment significantly enhanced the total sulfhydryl content, protein solubility, and zeta potential of MPs, while reducing carbonyl content, surface hydrophobicity, and particle size. MPs in the ABF group showed a higher α-helix proportion and a lower random coil content, along with a notable increase in intrinsic fluorescence intensity. Scanning electron microscopy (SEM) revealed a denser gel structure. Additionally, ABF effectively inhibited microbial growth in mutton, delayed pH increase, reduced thiobarbituric acid-reactive substances (TBARS) and total volatile basic nitrogen (TVB-N), and improved sensory scores, extending mutton shelf life by over 10 days. Therefore, the ABF effectively inhibited oxidation in MPs, maintained their structural integrity, and preserved mutton quality during super-chilling storage. Full article

The conformation of a glycosaminoglycan (GAG) carbohydrate biopolymer is dependent upon the ring puckering states of its constituent monosaccharide residues and the dihedral angles (φ, ψ) of the glycosidic linkages connecting these residues. In the context of GAGs, the monosaccharide residue iduronate (IdoA; the conjugate base of iduronic acid) is able to take on both chair and boat-like ring pucker states. All-atom explicit-solvent molecular dynamics simulations were applied to determine the extent to which IdoA ring pucker state affects the conformational preferences of (φ, ψ) in 16 different IdoA-containing disaccharides derived from the GAGs heparin/heparan sulfate and dermatan sulfate. Using the extended-system adaptive biasing force (eABF) method, the complete free-energy surface ΔG(φ, ψ) was computed for each disaccharide with its IdoA ring restrained separately to the ¹C₄, ²S_O, B_3,O, or ⁴C₁ ring pucker state. Global-minimum ΔG(φ, ψ) values resided within broad ΔG(φ, ψ) basins, and both ring pucker state and sulfation status influenced basin shape and size. Various sulfoforms of the disaccharide IdoAα1–4GlcNS had prominent secondary-minimum basins distinct from the global-minimum basins, and these secondary-minimum basins may manifest as metastable states in standard (nonbiased) molecular dynamics simulations on the 1-microsecond timescale. As such, the present results provide a reference for assessing (φ, ψ) sampling in nonbiased molecular dynamics simulations of GAGs and demonstrate the interplay between IdoA ring puckering, glycosidic linkage dihedral rotation, and sulfation status in contributing to GAG conformational preferences. Full article

Dissolved organic carbon (DOC) represents the most readily available and crucial carbon source for soil microorganisms, influencing their community structure, nutrient cycling, and metabolic functions. However, the interplay between functional genes and the organic components of DOC remains poorly understood. In this study, a 33-year fertilization experiment on black soil was carried out, setting up five fertilization treatments: unfertilized control (CK), nitrogen and potassium (NK), nitrogen, P and potassium (NPK), NPK plus straw (NPKS), and NPK plus manure (NPKM). The variation characteristics of soil DOC composition and carbon-degrading functional gene abundance under different fertilization treatments were systematically analyzed. The study found that applying chemical fertilizers combined with organic materials significantly increased soil organic carbon (SOC) and DOC contents in the thin-layer black soil of Gongzhuling. The soil DOC in this region is primarily derived from external inputs (Fresh plant-derived materials). Parallel factor analysis identified four fluorescent components: C1 as visible fulvic acid-like substances, C2 as humic acid-like substances, C3 as ultraviolet fulvic acid-like substances, and C4 as long-wavelength humic-like substances. Among these, NPK plus straw significantly enhanced the fluorescence intensity of the humic acid-like component (C2) and the total fluorescence intensity. The fluorescence intensity of the humic acid-like component increased by 36.0–208.9%, and the total fluorescence intensity increased by 23.8–270.9% compared to the CK. Moreover, the study found that the phylum composition of carbon-degrading microorganisms remained stable under different fertilization treatments. However, NPK plus straw significantly reduced the total abundance of carbon-degrading genes and influenced the composition and transformation of DOC by regulating the expression of key carbon-degrading genes ICL and abfA. These results offer new insights into the mechanisms by which fertilizer management affects the composition and stability of DOC in black soils via microbial functional gene pathways. Full article

Waterlogging is a major abiotic stress that restricts plant growth, productivity, and survival by disrupting root aeration and altering hormonal homeostasis. To elucidate the physiological and molecular responses associated with flooding tolerance in Liriodendron hybrids (Liriodendron chinense × Liriodendron tulipifera), this study investigated its morphological, physiological, and transcriptomic changes under 0, 1, 3, and 6 days of waterlogging. Roots exhibited rapid decay, while leaves showed delayed chlorosis and reduced chlorophyll content. Changes in antioxidant enzyme activities reflected enhanced antioxidant capacity, with superoxide dismutase (SOD) activity decreasing and peroxidase (POD) and catalase (CAT) activities increasing. Hormone measurements indicated organ-specific patterns, including abscisic acid (ABA) accumulation in leaves and decreased indole-3-acetic acid (IAA) and gibberellin (GA) levels in both roots and leaves. Transcriptome profiling revealed extensive transcriptional adjustments in hormone biosynthesis, signaling, and stress-responsive pathways, including divergent regulation of ABA-associated genes in leaves and roots and broad downregulation of auxin- and gibberellin-related genes. Key ABA biosynthetic genes (NCED1, ABA2) and signaling components (PYL4, PP2C, ABF) were upregulated in leaves but downregulated in roots, whereas auxin (YUC6) and gibberellin (GA20ox) genes were generally suppressed. These coordinated physiological and molecular responses suggest organ-differentiated adaptation to waterlogging in Liriodendron hybrids, highlighting candidate pathways and genes for further investigation and providing insights for improving flooding tolerance in woody species. Full article

Background: The global livestock industry faces pressure to reduce antimicrobial usage while maintaining animal health and productivity. Non-pharmaceutical interventions (NPIs) including probiotics, prebiotics, phytogenics, essential oils, organic acids, and enzymes have emerged as alternatives to antibiotic growth promoters. Commercial success depends on consumer acceptance and willingness to pay (WTP) for products from animals raised using these approaches. Objective: This systematic review synthesized peer-reviewed literature examining consumer knowledge, attitudes, perceptions, and WTP toward animal products produced using NPIs or marketed as antibiotic-free (ABF) to identify a critical gap in existing research. Methods: Following PRISMA 2020 guidelines, four databases (PubMed, Web of Science, Scopus, and Google Scholar) were searched for peer-reviewed studies published from January 2020 to December 2024. Inclusion criteria encompassed original research examining consumer perspectives toward NPIs or antibiotic-free (ABF) animal products. Narrative synthesis was employed due to study heterogeneity. Results: From 847 records, 15 studies met inclusion criteria. A critical finding was that virtually no peer-reviewed research directly examines consumer perceptions of specific NPIs such as probiotics, prebiotics, phytogenics, organic acids, or enzymes as feed additives. The included studies predominantly examined ABF production generally (60%) without specifying alternatives employed. Europe accounted for 80% of studies, while Asia accounted for 20%. Consumer awareness of agricultural antibiotic use was consistently low across contexts. Attitudes toward ABF products were favorable with one study reporting WTP premiums of 18–20%. Health consciousness was the strongest predictor of acceptance. Conclusions: The review highlights that while substantial literature exists on ABF products, no studies examine consumer perceptions of specific non-pharmaceutical interventions. Future research should investigate consumer responses to intervention specific labeling and communication strategies. Full article

Gray mold, caused by Botrytis cinerea, is a devastating disease of strawberry, with petal abscission rate (PAR) being a critical disease-avoidance trait. Rapid petal abscission removes a key infection site for the pathogen, thereby reducing disease incidence. To dissect the genetic basis of PAR, a segregating F₁ population was constructed from a cross between ‘Benihoppe’ (rapid abscission) and ‘Sweet Charlie’ (slow abscission). Utilizing BSR-Seq analysis of extreme bulks, five high-confidence quantitative trait loci (QTLs) were identified on chromosomes Fvb2-2, Fvb4-4, and Fvb6-3. These QTLs encompassed 672 candidate genes, with enrichment in “Plant hormone signal transduction” pathway. Integrated analysis of gene expression and SNPs identified 16 candidate genes, including those involved in flowering time (e.g., ELF3, HUA2 and AGL62) and plant hormone (e.g., ANT, RTE (ethylene), NDL2, FPF1 (auxin), and CYP707A7, ABF2 (abscisic acid) signaling, as well as calcium transport (ACA1, ECA3). Fourteen Kompetitive Allele-Specific PCR (KASP) markers were developed from candidate genes, with four markers showing significant correlations with PAR. This study provides the first genetic mapping of PAR in strawberry, revealing candidate genes and molecular markers that will facilitate the breeding of cultivars with improved gray mold resistance through enhanced petal abscission. Full article

Eutrophication threatens vulnerable plateau lakes, yet the gene-level microbial processes behind spatial heterogeneity of sediment carbon (C), nitrogen (N), phosphorus (P) and sulfur (S) cycling and their environmental driver remain unclear. This study first applies the high-throughput Quantitative Microbial Ecology Chip (QMEC) to quantify 71 functional genes involved in geochemical cycling in sediment of a large Chinese plateau lake, Erhai, aiming to elucidate how environmental factors shape the spatial distribution and coupling patterns of these genes. The results revealed that total functional gene abundance exhibited a pronounced south-to-north decline, with key genes (rbcL, mct, nirS, nosZ, phoD, pqqC and yedZ) being significantly higher in the southern sector (p < 0.05). Lignocellulose-degrading genes (abfA, xylA and mnp) exceeded 10⁶ copies g⁻¹ and were significantly enriched in the south, indicating faster organic-matter turnover. Denitrification dominated the nitrogen cycle, with nirS-type denitrifiers being overwhelmingly prevalent; genes associated with nitrate reduction (napA, narG) were also significantly more abundant in the south. Sediment total phosphorus (TP) was significantly correlated with genes involved in carbon fixation, methane production, nitrogen fixation and sulfur metabolism (Mantel test, p < 0.05), suggesting that TP is a key driver of microbial nutrient cycling in Erhai sediment. Furthermore, co-abundance of these functional genes was observed across all sites (Spearman correlation, p < 0.05), which in turn implies potential coupling of the major elemental cycles. Accordingly, the differentiation of the carbon, nitrogen, phosphorus and sulfur cycling genes and metabolic potential in the different sectors reveals heterogeneous microbial regulation of Erhai’s endogenous nutrient cycling. It highlights precision and differentiated management as a key for large lake restoration. Full article

This review presents soybean responses to drought, heat, and salinity within a signal–transcript–chromatin framework. In this framework, calcium/reactive oxygen species and abscisic acid cues converge on abscisic acid-responsive element binding factor (ABF/AREB), dehydration-responsive element binding protein (DREB), NAC, and heat shock factor (HSF) families. These processes are modulated by locus-specific chromatin and non-coding RNA layers. Base-resolved methylomes reveal a high level of CG methylation in the gene body, strong CHG methylation in heterochromatin, and dynamic CHH ‘islands’ at the borders of transposable elements. CHH methylation increases over that of transposable elements during seed development, and GmDMEa editing is associated with seed size. Chromatin studies in soybean and model species implicate the reconfiguration of salt-responsive histone H3 lysine 27 trimethylation (H3K27me3) in G. max and heat-linked H2A.Z dynamics at thermoresponsive promoters characterized in Arabidopsis and other plants, suggesting that a conserved chromatin layer likely operates in soybean. miR169–NF-YA, miR398–Cu/Zn Superoxide Dismutases(CSD)/copper chaperone of CSD(CCS), miR393–transporter inhibitor response1/auxin signaling F-box (TIR1/AFB), and miR396–growth regulating factors (GRF) operate across leaves, roots, and nodules. Overexpression of lncRNA77580 enhances drought tolerance, but with context-dependent trade-offs under salinity. Single-nucleus and spatial atlases anchor these circuits in cell types and microenvironments relevant to stress and symbiosis. We present translational routes, sentinel epimarkers (bisulfite amplicons, CUT&Tag), haplotype-by-epigenotype prediction, and precise cis-regulatory editing to accelerate marker development, genomic prediction and the breeding of resilient soybean varieties with stable yields. Full article

Boron exerts regulatory control over various aspects of plant growth and morphogenesis, and the application of boron prior to anthesis has been recognized as a critical agronomic practice. However, the regulatory mechanisms by which boron influences fruit set and early ovary development in pear remain to be elucidated. In this study, boron application was used at three stages, including pre-flowering, full-flowering, and early fruiting in the ‘Kuerle Xiangli’ (Pyrus sinkiangensis Yu), with a focus on cell expansion and endogenous phytohormone. As a result, treatment with 0.3% boric acid significantly increased endogenous boron concentrations in both leaves and ovaries and enhanced ovary fresh weight as well as both longitudinal and transverse diameters. Histological analysis revealed pronounced cell expansion at 5, 10, and 15 days after pollination (DAP) following boron treatment. Furthermore, gibberellin and trans-zeatin concentrations at 5 and 10 DAP were significantly elevated, while the concentrations of abscisic acid and auxin were markedly reduced. Quantitative real-time PCR (qRT-PCR) analysis demonstrated that boron positively regulates the expression of auxin-related genes, like PbARFH, PbARFD and PbSAUR76-like. In the gibberellin signaling pathway, the expression PbGID1, PbGID1C-like and PbGID2 was activated to drive cell expansion with the boron application. In the abscisic acid signaling pathway, boron treatment induced downregulation of PbSRK2.4, PbABF2, and PbABF2-like in the ovary. Furthermore, boron treatment induced high expression of hormone signaling genes in cytokinin, brassinolide, jasmonic acid and salicylic acid signaling pathways. These findings provide insights into the mechanisms of cell expansion and hormonal changes by which boron modulates early ovary development, offering a basis for improving fruit quality through optimized boron application. Full article

Mitogen-Activated Protein Kinases (MAPKs) play crucial roles in plant stress signaling, but the mechanisms of MAPK genes in Portulaca oleracea remain functionally uncharacterized. In this study, transcriptomic screening of P. oleracea under salt stress identified PoMPK3 as a candidate gene, showing significant root-specific upregulation. Phylogenetic analysis classified it as a Group A MAPK protein, and subcellular localization confirmed its membrane association. Heterologous expression of PoMPK3 in Arabidopsis thaliana significantly enhanced salt tolerance, as evidenced by improved seed germination rates, longer primary roots, increased biomass, and reduced stress symptoms. Mechanistically, PoMPK3 expression activated ABA signaling, leading to increased ABA levels and upregulation of AtNCED3, AtPYR1, and AtABF3. Furthermore, it strengthened the antioxidant defense, as evidenced by elevated antioxidant enzyme activity, leading to a reduction in oxidative stress. The transgenic lines also demonstrated enhanced osmotic adjustment through osmolytes accumulation and ionic homeostasis, evidenced by tissue-specific Na⁺/K⁺ ratios (low in shoots, high in roots) resulting from the concerted upregulation of AtSOS1, AtNHX1, and AtHKT1. In addition, gene co-expression network analysis and molecular docking predicted phosphorylation of WRKY transcription factors, suggesting a novel mechanism for transcriptome reprogramming. Collectively, our findings not only advance the understanding of salt tolerance mechanisms in purslane but also identify PoMPK3 as a key genetic determinant, thereby laying the foundation for its use in breeding programs aimed at enhancing salt stress resilience in crops. Full article