Search Results (5,052)

As sessile organisms, plants must continuously perceive and integrate external environmental cues with internal developmental signals to optimize growth, reproduction, and survival. Central to this adaptive capacity is the ubiquitin-proteasome system (UPS), the primary pathway for selective protein degradation in eukaryotes. Within the UPS, BTB (Broad-Complex, Tramtrack, and Bric-à-brac) proteins serve as critical substrate adaptors for the Cullin3 (CUL3)-based E3 ubiquitin ligase complex. These proteins play indispensable roles in plant growth, development, hormone signaling, and responses to abiotic stresses. Recent advances have revealed the remarkable functional versatility of BTB proteins, implicating them in the regulation of photomorphogenesis, root architecture, flowering time, stress resilience, and yield-related traits. With 80 BTB-encoding genes in Arabidopsis thaliana and key orthologs identified in major crops—including of rice (Oryza sativa), soybean (Glycine max), and maize (Zea mays)—BTB proteins act as molecular “bridges” that integrate developmental programs with environmental stress signals. This review summarizes the structural features, classification, and multifaceted functions of plant BTB proteins, with an emphasis on their roles in growth regulation, abiotic stress tolerance, light signaling, and agricultural productivity. We further discuss their mechanisms in ubiquitin-dependent proteolysis, transcriptional regulation, and signal integration, offering insights into their potential as targets for engineering climate-resilient crops and advancing sustainable agriculture. Full article

Background: Obstructive sleep apnea (OSA) is a complex and diverse disorder affecting almost one billion individuals worldwide. Severity of untreated OSA, measured by the apnea–hypopnea index (AHI), is noted to be associated with an increased all-cause and cardiovascular mortality. Although widely used, AHI insufficiently captures disease variability as there is a poor correlation of symptoms with the AHI. There lies individual susceptibility to the effects of OSA and that parameter alone poorly predicts cardiovascular outcomes without considering intermittent hypoxia and the hemodynamic effects of OSA. Recognition of clinical, polysomnographic, and neurophysiological phenotypes offers an opportunity to refine diagnosis, prognosis, and management strategies. Methods: We conducted a narrative synthesis of the literature involving 70 articles, focusing on quantitative and qualitative (Q2) clinical traits, polysomnographic parameters, and mechanistic insights that enable subclassification of OSA beyond AHI. Evidence from large cohorts, animal models, and pathophysiological studies were reviewed. Results: Phenotyping based on a Q2 analysis of polysomnographic respiratory event predominance, event duration, positional and REM dependence, hypoxic burden, and arousal characteristics reveals significant heterogeneity in risk profiles and therapeutic response. Apnea-predominant OSA correlates with a higher oxygen desaturation index and Epworth sleepiness scale. Hypopnea-predominant OSA correlates with a cardiometabolic disease burden and may show a more favorable response to surgical therapies. The duration of respiratory events is related to cardiovascular risk, and REM-predominant OSA independently predicts hypertension and adverse cardiovascular outcomes. Supine-predominant OSA demonstrates treatment responsiveness to auto-positive airway pressure and positional therapy. Respiratory effort–related arousals (RERAs), RERA-predominant OSA and the broader respiratory disturbance index (RDI) provide neurophysiological insight often missed by AHI-based classifications. Hypoxic burden, rather than AHI, emerged as a superior predictor of cardiovascular events and mortality. Finally, arousal frequency and periodic limb movements independently predict cardiovascular morbidity. Conclusions: Employing Q2-based phenotyping that incorporates clinical, polysomnographic, and neurophysiological markers improves risk stratification, prognosis, and individualized management of OSA. Future investigations should prioritize integrating phenotypic subclassification into diagnostic criteria and treatment planning to advance precision medicine in sleep apnea care. Full article

Epigenetic diversity contributes to phenotypic plasticity and environmental responsiveness in Citrus spp. In this work, genome-wide DNA methylation was analyzed in 49 accessions representing six Citrus species, hybrids, varieties, and cultivars from the Greek National Germplasm Collection. Substantial variation in global DNA methylation was detected, while the epigenetic diversity indices did not differ significantly among taxa. The highest values were observed in Citrus × aurantium var. sinensis (orange) varieties (P_epi = 77.33%, Na = 1.55, h = 0.14, I_epi = 0.24), whereas the lowest were recorded in Citrus × aurantifolia (lime) (P_epi = 18.67%, Na = 0.37, h = 0.09, I_epi = 0.13), reflecting potential methylation restructuring impacted by hybridization and selection. Epigenetic and genetic diversity were significantly different. Principal coordinate analyses (PCoA) of epigenetic data revealed limited concordance to taxonomy, except for unmethylated loci, the latter exhibiting similar data to genetic (SSR) results in which groups reflected the taxonomic genealogy. Epigenetic and genetic distances were uncoupled, and associations between epigenetic diversity (P_epi, h, I_epi) and traits directly or indirectly related to fitness (fruit weight, dry matter content, ascorbic acid concentration), were weak. These findings indicate that epigenetic diversity represents an independent layer of variation in Citrus germplasm with potential relevance for breeding, conservation and environmental resilience. Full article

Compost application to soil is an effective strategy to enhance soil fertility, promote plant growth, and support sustainable agriculture. Nevertheless, the variability in the responses of plants to compost amendments across different compost types, concentrations, exposure durations, application media, and across different physiological traits of plants is not well understood. In this study, we performed a meta-analysis using data from 92 peer-reviewed scientific articles to better understand the effect of compost amendments on plant physiological, biochemical, and yield traits. The results of this study showed that compost amendment significantly improved plant growth parameters, and the increase in shoot biomass and plant height was the highest (~19.4–42.7%), followed by root length (20.4%) and root biomass (19.7%), indicating the important role of compost in promoting root development. In addition, photosynthetic efficiency was significantly enhanced, and total chlorophyll and carotenoid content increased by 13.5–49.1%. The yield-related traits, total yield, and 100-grain weight responded positively and significantly increased by ~18%. There were variations among different plant species and different exposure conditions. The mechanistic interaction between compost components, soil agrochemical properties, and plant physiological and yield responses should be further explored to maximize the benefits of compost application in sustainable agriculture. Full article

Soil salinity remains a major constraint to rice productivity, particularly during early developmental stages when plants are highly sensitive to osmotic and ionic stress. In this study, we evaluated 201 genetically diverse rice genotypes from the 3K Rice Diversity Panel to investigate stage-specific mechanisms of salinity tolerance and develop machine learning-based predictive models for rapid phenotypic screening. Morphological and physiological traits were measured under control and saline conditions at germination and early seedling stages to derive Stress Tolerance Indices (STIs). The average membership function value (AMFV), calculated from multi-trait STI profiles, effectively captured variation in salinity responses and enabled classification of genotypes into five tolerance categories. Genome-wide association analysis using high-density SNP markers identified 36 significant marker–trait associations, including potentially novel SNPs on chromosomes 1 and 12. Several loci co-localized with candidate genes (LTR1, LGF1, OsCPS4, OsNCX7, and OsNHX4), while functional SNPs within genes (OsDRP2C, RLCK168, and OsMed37_2) and non-synonymous variants (qSVII11.1 and qSNaK3.1) further supported their candidacy in salinity tolerance. Mining favourable SNPs of causal genes identified superior multilocus combinations consistent with STI-based phenotypic patterns, with genotype 91-382 emerging as the strongest performer, exhibiting enhanced Na⁺ exclusion, K⁺ retention, and biomass resilience across developmental stages. To address multicollinearity among STI traits, we applied cross-validated LASSO (germination) and Elastic Net (early seedling) models, achieving high predictive accuracy and revealing a developmental shift from biomass-driven tolerance at germination to ion-regulatory processes at the seedling stage. Independent validation showed strong agreement between predicted and observed AMFVs. By integrating physiological indices, GWAS-derived SNP signals, and regularized machine learning approaches, this study provides a robust framework for identifying elite donors and accelerating breeding for salt-tolerant rice. Full article

We conducted this experiment with the aim of investigating the effects of different noise levels from ventilation fans on the growth and slaughter performance, meat quality, blood parameters, and feeding behavior of geese from 21 to 70 days of age. A total of 108 male geese (21-day-old) were randomly assigned to one of three conditions: a control group (no additional fan noise), low-noise treatment (65–75 dB), and high-noise treatment (85–95 dB). Each treatment included six replicates, with six geese per replicate. The results showed that neither ventilation fan noise level significantly affected growth performance, feeding behavior, slaughter performance, or major meat quality traits (p > 0.05). Compared with the control group, noise exposure significantly reduced circulating adrenocorticotropic hormone and corticosterone concentrations (p < 0.05), and the low-noise group exhibited significantly reduced cortisol concentrations (p < 0.05), while the high-noise group had increased cortisol concentrations. Under noise exposure conditions, no statistically significant effects were observed on superoxide dismutase, total antioxidant capacity, malondialdehyde concentration, catalase, and glutathione peroxidase activities compared with the control group (p > 0.05). Overall, prolonged noise stimulation (65–75 dB and 85–95 dB) alleviated stress responses in commercial geese aged 21–70 days, without negatively affecting their growth performance, slaughter performance, meat quality, or feeding behavior. Full article

The Qinghai–Tibet Plateau and surrounding mountain regions form one of the world’s most distinctive freshwater environmental gradients. Schizothoracinae are among the most representative endemic fish lineages in these systems and provide a useful model for studying how drainage history, genome evolution, adaptation, and conservation interact. In this review, we synthesize schizothoracine research within an environment–evolution–conservation framework. We examine how drainage history and connectivity shape divergence and gene exchange, how polyploidy and genome remodeling provide the genomic background for adaptive inference, and how phenotypic and population-genomic evidence can be translated into conservation units and management priorities. Across current studies, cold-associated metabolic remodeling and UV-related DNA damage response and repair emerge as the most recurrent molecular themes, whereas hypoxia-related signals are more context-dependent. We further show that morphology, otolith chemistry, age–growth traits, and population structure can strengthen MU/ESU interpretation when integrated with genomic evidence. Future progress will depend on broader chromosome-level genome coverage, more systematic comparison of structural genomic variation, standardized stressor-linked designs, and denser sampling in geomorphic transition zones and putative hybrid regions. Full article

Microcystin (MC) contamination of surface waters threatens ecosystems and public health. Nature-based solutions such as Multi-Soil-Layering (MSL) systems have been used for MC remediation. However, the biological mechanisms controlling MC degradation remain unclear. The present study investigates microbial community responses in two MSL systems with different clay contents (8% and 54%) exposed to MC-contaminated inputs (well water and eutrophied lake water). Samples were analysed before and after treatment using quantitative PCR (qPCR) to quantify the mlrA gene (encoding microcystinase) and its bacterial hosts. Next-generation sequencing (NGS) was used to assess microbial diversity, while the FAPROTAX database was used to predict functional characteristics. Results showed that MC was mainly adsorbed in pozzolan layers, while mlrA gene abundance and MC-degrading bacteria were higher in soil mixture layers. The presence of mlrA and associated bacteria was most pronounced in lake inflow samples, indicating intrinsic MC Biodegradation potential. Taxonomic analysis revealed dominant phyla including Proteobacteria, Actinobacteriota, Firmicutes, Chloroflexi and Bacteroidota. Functional analysis identified dominant traits such as chemoheterotrophy and aerobic metabolism. These findings provide new insights into microbial interactions in MSL systems and contribute to the optimisation of water treatment strategies for MC-contaminated environments. Full article

Drought stress severely limits plant growth and productivity, yet the molecular basis of drought tolerance and post-drought recovery remains incompletely understood in many forage legumes. Medicago ruthenica is a perennial legume native to arid and cold regions and exhibits strong drought resilience. Results: We integrated key physiological traits related to stomatal regulation, photosynthesis, osmotic adjustment and antioxidant defense with RNA-seq across four stages (well-watered control, CK; drought for 9 days, D9; drought for 12 days, D12; and rewatering for 4 days, RW). Drought triggered stage-dependent physiological shifts, and transcriptome profiling identified >3000 drought- and rewatering-responsive genes enriched in primary metabolism, redox homeostasis and hormone signaling. WGCNA highlighted two drought-associated modules (MEcyan and MEcoral1) and prioritized three hub transcription factors for functional validation: 861 (AP2/ERF), 22 (WRKY) and 89 (bZIP). Overexpression of each gene in tobacco improved drought tolerance, as indicated by enhanced growth/root traits, increased osmolyte accumulation and antioxidant enzyme activities, and reduced membrane damage. Conclusions: Together, these results provide an integrated view of drought stress response and recovery in M. ruthenica and identify 861, 22 and 89 as candidate regulatory genes for engineering drought resilience in legumes. Full article

High-temperature (HT) stress during flowering causes male sterility and yield loss in soybean. MYB transcription factors are key regulators under abiotic stress, yet their function and mechanism in regulating male fertility under HT stress in soybean are not fully understood. In this study, a MYB transcription factor GmMYB21a in soybean was identified. GmMYB21a was induced by HT stress in soybean restorer line and was specifically expressed in pollen. Through overexpression and knockout experiments, we demonstrated that GmMYB21a positively regulated pollen viability and germination under HT stress. Overexpression of GmMYB21a significantly enhanced these traits in restorer line, whereas knockout plants exhibited the opposite effect. Transcriptome sequencing revealed that GmMYB21a overexpression upregulated numerous stress-responsive genes, particularly those involved in flavonoid biosynthesis and sugar metabolism. In addition, molecular experiments confirmed that GmMYB21a bound to the promoter of flavonoid synthesis gene GmCHI2-A and promoted its expression. In summary, our research indicated GmMYB21a enhanced the HT-tolerance of male fertility in soybean restorer line through reactive oxygen species scavenging and flavonoid synthesis. This study aims to elucidate the thermotolerance mechanism in soybean male fertility and identify genetic resources for breeding HT-tolerant restorer lines. Full article

Soil salinization poses a severe threat to global wheat production, yet the physiological mechanisms underlying photosynthetic responses to neutral, alkaline, and combined salt stress remain poorly understood. This study systematically evaluated the photosynthetic physiology and salt tolerance of six spring wheat genotypes under three types of salt stress at varying concentrations. By integrating phenotypic data, gas exchange parameters, chlorophyll fluorescence indices, and biomass measurements, and applying structural equation modeling and multivariate analysis, key traits regulating biomass were identified. The results revealed significant interactions among salt stress type, genotype, and concentration on photosynthetic parameters. Structural equation modeling analysis revealed that under neutral salt stress, both gas exchange parameters and chlorophyll content had significant direct effects on seedling biomass, with standardized path coefficients of 0.421 and 0.400, respectively. Under alkaline and combined salt stresses, only chlorophyll content showed a significant direct effect on biomass, with standardized path coefficients of 0.873 and 0.790, respectively. Multiple regression analysis further identified key photosynthetic factors influencing growth under different stress types. Under neutral salt stress, phi (Ro) and E significantly affected biomass, whereas under alkaline and combined salt stresses, biomass was primarily co-regulated by phi (Ro) and phi (Eo). Based on a comprehensive evaluation of salt tolerance index, damage index, and biomass response, genotypes W06 and W02 exhibited the strongest overall salt tolerance. This study systematically elucidates the differential response mechanisms of photosynthesis in spring wheat under distinct salt stress types, providing an important theoretical basis and elite germplasm resources for breeding salt-tolerant wheat varieties. Full article

Background/Objectives: Salinity stress limits agricultural production and threatens global food security. Faba bean (Vicia faba L.) is an important legume crop, and identifying salt-stress-responsive genes may support an improvement in salt response. This study aimed to identify intronless genes in faba bean, screen candidate genes associated with salt-stress responses, and develop a KASP marker for salt-response evaluation. Methods: Intronless genes were identified from the faba bean reference genome. Transcriptome analysis was conducted in roots and leaves of two cultivars, Sucan 4 and Yundou 1183, under 150 mM NaCl treatment and control conditions. Candidate genes were examined by expression analysis, functional annotation, PPI prediction, and a luciferase complementation assay. A KASP marker was developed from an SNP within the VfERF1A locus and tested in 97 accessions. Results: A total of 7581 intronless genes were identified, accounting for 20.69% of annotated genes. Fifteen intronless genes were significantly differentially expressed in both roots and leaves of the two cultivars under salt treatment. Functional annotation suggested that VfERF1A and VfHSP17.8 may be involved in salt-stress responses. PPI prediction and the LUC assay provided preliminary support for a possible association of VfERF1A with VfEIN2. The VfERF1A-based KASP marker showed clear genotype clustering, and the two homozygous classes differed significantly in QYmax, relative shoot fresh weight, and relative plant height under salt treatment (p < 0.05). The preliminary predictive accuracy for QYmax was 86.36%. Conclusions: These results provide a genome-wide resource of intronless genes in faba bean, identify candidate genes associated with salt-stress responses, and describe a preliminary KASP marker associated with salt-response traits. Further validation in independent populations, under diverse environmental conditions, and with additional functional evidence is still required. Full article

Salinity stress impairs maize growth by inducing osmotic stress, pigment degradation, and ionic imbalance, particularly during early seedling development. This study investigated the morpho-physiological and ionic responses of different maize genotypes exposed to increasing salinity levels (control, 3, 6, and 9 dS/m) at the seedling stage. Salinity caused a reduction in biomass accumulation (shoot fresh weight and shoot dry weight), plant height, and K⁺/Na⁺ ratio, with pronounced effects under severe stress. Significant genotypic variability was detected for photosynthetic pigments (chlorophyll a, chlorophyll b, total chlorophyll and carotenoids) growth traits, and ionic regulation, indicating diverse physiological adaptation strategies. Stress tolerance indices and multivariate analysis revealed that chlorophyll stability, carotenoid accumulation, and maintenance of ionic homeostasis (K⁺/Na⁺ ratio) were the dominant physiological determinants of salinity tolerance. Additionally, principal component analysis showed a shift from biomass-driven variation under non-stress conditions to pigment- and ion-driven variation under higher salinity. Based on the results, genotypes BML 6 and HKI 163 maintained higher pigment content and improved K⁺/Na⁺ balance, enabling better growth under saline conditions. These findings highlight key physiological traits underlying salinity tolerance and provide insight into early-stage adaptive mechanisms in maize. Full article

Drought is a major constraint on crop productivity, and microbial inoculants are increasingly explored to mitigate plant water stress. However, most inoculant discovery pipelines rely on trait-based screening performed outside the ecological context in which beneficial plant-microbe interactions naturally arise. In natural soils, drought-exposed plants can reshape the rhizosphere environment by altering carbon allocation and root exudation, thereby selectively recruiting microorganisms compatible with water-limited conditions and effectively performing an ecological pre-selection. Here, we captured this process during early seedling establishment and leveraged drought-driven rhizosphere recruitment as a nature-guided strategy to nominate bacterial inoculant candidates. Tomato seedlings were grown in natural agricultural soil microcosms under well-watered and drought-stressed regimes, and cultivable bacteria were comparatively isolated from rhizosphere and bulk soil fractions. Recruitment-prioritized isolates were subsequently characterized through biochemical assays and genome-informed analyses to provide functional and taxonomic context and were evaluated in early inoculation assays under water stress. Drought-recruited isolates displayed distinct plant-associated responses, and genome-scale taxonomy indicated that one drought-associated isolate represents a genomically distinct lineage within the genus Paracoccus. Together, these findings highlight drought-driven rhizosphere recruitment as an ecologically grounded framework for identifying stress-compatible bacterial candidates and uncovering previously undescribed rhizosphere diversity. Full article

Plant growth-promoting rhizobacteria (PGPR) are considered promising bio-inoculants for poplar production, but their effects can vary depending on bacterial strain, host genotype, and growth environment. In this study, we evaluated the responses of ten poplar clones representing three taxonomic groups to five indigenous PGPR strains under greenhouse and open-field nursery conditions. Under greenhouse conditions, Priestia aryabhattai GJRr2, Variovorax boronicumulans HNRr1, and a mixed inoculum (Mix) showed the most consistent positive effects. Plant height increased from 86.1 ± 5.6 cm in the control to 156.0 ± 9.4 cm in the GJRr2 treatment, whereas HNRr1 produced the greatest stem diameter (9.01 ± 0.26 mm) and total fresh weight (94.0 ± 6.0 g). Clone identity explained a larger independent fraction of growth variation than bacterial strain, and the strongest integrated responses were observed in I-476, Dorskamp, and Eco28. Field responses were generally weaker, but GJRr2 and Mix still increased height, DBH, and stem volume, whereas ORa was associated with negative responses in these traits. These results demonstrate that PGPR effects in poplar are strain-specific, clone-dependent, and environmentally contingent, indicating that inoculant selection should account for both host genotype and performance stability across growth conditions. Full article