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Winter chilling has long been considered the primary driver of bud dormancy release in woody perennials. However, the cellular mechanisms underlying dormancy transitions remain poorly understood. This study aimed to investigate the relationship between dormancy depth, cell cycle activity, and cellular ultrastructure in grapevine buds across the dormancy cycle. Bud dormancy progression in single node explants of Vitis vinifera cv. Cabernet Sauvignon was monitored from early autumn dormancy to the end of winter. Dormancy depth was quantified as the time to 50% bud burst under forcing conditions. Cell cycle status was assessed using quantitative flow cytometry, while the cellular ultrastructure of the shoot apical meristem was examined by transmission electron microscopy. Dormancy depth declined dramatically from over 280 days in early autumn to ca 50 days in late autumn, despite negligible chilling exposure during this period. Following chilling exposure in winter, the depth of dormancy declined to ca 20 days. Strikingly, flow cytometry revealed that the majority of cells remained arrested in the G1 phase of mitosis throughout this period, regardless of dormancy depth, supported by ultrastructural analysis of the shoot apical meristem. Starch grains were abundant in both deeply dormant pre-winter buds (no chilling) and winter buds (with chilling), indicating that starch dynamics may be regulated independently of both dormancy status and chilling exposure. These findings demonstrate temporal uncoupling of dormancy release from cell cycle reactivation, challenging assumptions that dormancy release is directly linked to both chilling and cell cycle activation. Our results establish that in grapevine, the transition to growth competence occurs independently of detectable cell division and can precede significant winter chilling accumulation. This work provides new insights into the cellular basis of dormancy regulation in woody perennials and establishes a methodological framework for dissecting this relationship in other species.

Histone methylation is an important epigenetic mechanism that regulates plant development and stress responses, but its role in postharvest fruit chilling injury remains unknown. Here, we identified a cold-inducible SET domain protein, MaSET40, in banana (Musa acuminata) and found that it functions as a trimethylation of histone H3 lysine 36 (H3K36me3) methyltransferase. Transient overexpression of MaSET40 in banana fruit peel accelerated chilling injury, whereas virus-induced silencing of MaSET40 alleviated cold-induced peel damage. Transcriptome profiling revealed that MaSET40 activates genes involved in reactive oxygen species (ROS) accumulation and membrane lipid degradation, including MaPPO1, MaPPO3, MaRBOHB, Malipase, MaPLA2, and MaLOX3.1. Chromatin immunoprecipitation followed by quantitative PCR (ChIP-qPCR) further showed that MaSET40 increased H3K36me3 enrichment at these gene loci, accompanied by higher transcript levels. These results reveal an H3K36me3-mediated epigenetic mechanism that promotes chilling injury in postharvest banana fruit and identify MaSET40 as a potential target for improving cold tolerance in tropical fruits.

Understanding the genetic basis of adaptation traits including chilling requirements, flowering and fruiting is essential for developing apricot cultivars adapted to changing climatic conditions and for extending the apricot production calendar. The objective of this study is to detect and finely identify marker-trait associations linked to these adaptation traits including chilling requirements in apricot, using an R-based workflow developed with agroclimatic functions. In this study, high-density GBS-based linkage maps previously developed for two biparental populations ('Bergeron' × 'Currot' and 'Goldrich' × 'Currot') were used to analyze the genetic basis of key adaptation traits, including chilling requirement (CR), blooming date (BD), fruit development period (FDP), and ripening time (RT), through Genome-Wide Association (GWAS) and Quantitative Trait Locus (QTL) analyses. Phenotypic evaluation over eight years revealed wide variability across genotypes and strong correlations between CR and BD, particularly when using Chill Portions as a metric. Genome-wide association and QTL mapping consistently identified major loci on linkage group (LG) 1 for BD and CR, and on LG4 for FDP and RT, explaining up to 59% of phenotypic variance. The candidate gene (qMD4.1 ANAC072), upon analysis, revealed the involvement of epigenetic regulators, cold-responsive proteins, and transcription factors, offering plausible functional links between genotype and phenotype. These findings provide novel insights into the genetic control of dormancy and phenological traits in apricot and represent a valuable genomic resource for marker-assisted breeding programs aimed at improving climatic resilience and extending the harvest.

Coral larval settlement constitutes a pivotal bottleneck in reef persistence, restoration efforts, and the development of assisted conservation strategies such as cryopreservation. Beyond survival, the ability of larvae to retain settlement competence following cryopreservation-related stress is essential for the successful application of these approaches. Despite its ecological significance, the mechanistic basis underlying settlement induction remains incompletely understood. Here, we systematically investigate the interactive effects of low temperature, water-soluble chemical cues, and lipid-based treatments on the settlement competence of Pocillopora acuta larvae, with the aim of also exploring the potential of cryopreservation-related stressor as alternative settlement-inducing treatments. Larvae were subjected to controlled chilling regimes, both independently and in combination with a suite of chemical agents across a range of concentrations and exposure durations. Settlement responses were benchmarked against induction by crustose coralline algae (CCA), a well-established natural cue. To disentangle thermal and chemical influences, parallel experiments were conducted under room temperature conditions. In addition, lipid-based delivery systems, including phospholipid and fatty acid liposomes, were evaluated for their potential to enhance settlement competence. Our results reveal that low-temperature exposure supported larval settlement competence at low to intermediate chemical concentrations (0.1-1 M), whereas higher concentrations (2 M) result in rapid loss of viability within 2 h. Settlement success ranged from 11% to 44%, with a peak of 66.6% achieved following exposure to 0.5 M propylene glycol for 2 h. Notably, the combined application of chilling and CCA resulted in reduced settlement relative to either cue alone, suggesting potential antagonistic interactions. Under room temperature conditions, chemical treatments elicited limited and variable settlement responses (≤33%), with methanol showing the highest post-treatment attachment and subsequent development. In contrast, lipid-based treatments failed to induce settlement or metamorphosis. Collectively, these findings demonstrate the remarkable plasticity of larval settlement responses in P. acuta and show that chilling and selected cryopreservation-related treatments do not preclude settlement competence under the conditions tested. Furthermore, some of these treatments may represent promising alternative approaches for inducing settlement under controlled laboratory conditions, and highlights new avenues for enhancing larval settlement for coral reef restoration.

The expansion of pistachio cultivation into new environments requires precise phenological characterization to ensure reproductive success and adaptive management. This study aimed to (i) develop a comprehensive BBCH scale for pistachio, (ii) evaluate the reproductive and vegetative development of cultivars 'Kerman', 'Peters', and 'Amarillo-M' under arid conditions of San Juan, Argentina, and (iii) determine the chilling and heat requirements for flowering and fruit maturation. The adapted BBCH scale encompasses 40 detailed developmental stages, covering vegetative growth, flowering, fruit development, ripening, and leaf senescence. This standardized framework integrates and refines previous descriptors, enabling consistent monitoring of both male and female cultivars and facilitating comparisons across studies and environments. Phenological observations were conducted over three seasons (2022-2025) in a commercial orchard located in an arid region south of San Juan Province, combining field surveys with bioclimatic indices. Results revealed marked interannual variability in flowering synchrony associated with chill accumulation. In 2023, insufficient chilling led to delayed and extended male flowering, disrupting overlap with 'Kerman'. Fruit development showed consistent thermal requirements but advanced markedly in 2024. Overall, the proposed BBCH scale provides a robust framework for monitoring pistachio phenology and supports climate-resilient orchard management and regional suitability assessments.

Low temperature severely restricts plant growth and development. Medicago falcata is an important germplasm resource for alfalfa breeding because of its strong adaptability and tolerance to abiotic stresses, particularly low-temperature stress. MicroRNAs (miRNAs) are key regulators of stress-responsive genes and modulate plant adaptation to stress by directing transcript cleavage or translational repression. However, the roles of miRNAs in low-temperature response mechanisms in M. falcata remain largely unclear. Here, we constructed miRNA libraries from M. falcata roots grown under normal or low-temperature conditions. High-throughput sequencing identified 442 miRNAs, including 245 known and 197 novel miRNAs. Among these, 74 were putatively upregulated and 37 were putatively downregulated under chilling and freezing treatments. Based on degradome sequencing, 193 target genes involved in diverse biological processes were predicted. The M. falcata MfbZIP transcription factor family, consisting of 41 members across six subfamilies, responded to the cold treatments. Of these, MfbZIP10, a nuclear-localized protein homologous to a bZIP transcription factor in M. truncatula, showed the most significant response to cold stress in stems and roots. miR408-5p was responsive to chilling and freezing, and could cleave MfbZIP10 transcripts in a transient assay, as determined by RLM-RACE analysis. Physiological analyses and gene expression profiling of transgenic lines further demonstrated that the miR408-5p-MfbZIP10 module plays a vital role in low-temperature stress responses, with MfbZIP10 functioning as a key regulator by modulating physiological traits and the expression of genes in multiple signaling pathways. Our results identified candidate cold-responsive miRNAs in M. falcata and predicted their target genes involved in diverse biological processes. miR408-5p was found to target MfbZIP transcription factors in response to cold stress. Physiological characterization and quantitative expression analyses of MfbZIP10 transgenic lines showed that the miR408-5p-MfbZIP10 module plays a crucial regulatory role in low-temperature adaptation. miRNA sequencing and target gene identification provide new insights into miRNA-mediated regulatory mechanisms in M. falcata. These findings may facilitate the development of cold-tolerant forage legume crops through genetic improvement.

In 2018, proposed changes to the public charge rule-amid intensified anti-immigrant rhetoric and heterogeneous local immigration enforcement-were widely publicized. These changes have been linked to reduced health care access among Hispanic populations, potentially increasing human immunodeficiency virus (HIV) risk, yet little is known about how the local policy context shapes these health impacts. This study examined how shifts in immigration policy and rhetoric post-2018 affected Hispanic HIV incidence rates across antisanctuary and sanctuary counties in the United States. County-level HIV incidence rates for 2010-2022 were obtained from AIDSVu.4 Counties were sorted into antisanctuary counties, sanctuary counties, and baseline counties using a county-level policy scoring system from the Immigrant Legal Resource Center. A triple difference-in-differences model estimated changes in the HIV incidence rates among Hispanic populations after 2018 by county type using the HIV incidence rates among White populations as a comparison. The HIV incidence rates among Black populations were included as placebo tests. Triple difference-in-differences models estimated a statistically significant 16.8% increase in the HIV incidence rates among Hispanic populations in antisanctuary counties relative to baseline counties after 2018. Estimates for Black populations were not statistically significant, and point estimates were negative, opposite in direction to those for Hispanic populations, supporting the interpretation that post-2018 shifts in immigration policy uniquely affected Hispanic populations. The results from this study indicate that immigration policy can work against public health policy to end the HIV epidemic. The HIV incidence rates among Hispanic populations may have increased because of fear and the chilling effects of the changes in immigration policy. The implications extend beyond HIV, indicating that anti-immigrant policies could lead to deterioration in a wide range of health outcomes.

Vegetable Solanaceae crops-tomato, pepper, eggplant, and potato-are increasingly cultivated in controlled environments where light is managed both as an energy source and as a developmental and stress-regulatory signal. Programmable spectra, photoperiods, and intensities interact with heat, drought, salinity, chilling, and nutrient limitation, generating complex physiological responses that cannot be explained by transcriptional regulation alone. This review highlights post-transcriptional RNA regulation as a key interface linking light perception with stress adaptation in vegetable Solanaceae. We focus on four regulatory layers-alternative splicing, RNA stability and decay, small RNAs pathways, and translational control-that determine which transcripts are processed, stabilized, degraded, or translated under specific environmental histories. Evidence from tomato, pepper, and potato indicates that RNA-level regulation contributes to stress responses, developmental flexibility, and genotype-specific acclimation. However, direct mechanistic links between defined photoreceptor pathways and specific post-transcriptional processes remain limited in Solanaceae; therefore, mechanisms established in Arabidopsis and other model plants are treated here as testable hypotheses rather than confirmed crop mechanisms. We further discuss how machine learning can integrate multi-omics and environmental datasets to identify predictive regulatory modules connecting light regimes with stress resilience and crop performance. Progress in this field will depend on experiments that combine precise light and microclimate monitoring with isoform-resolved transcriptomics, small RNAs/degradome analyses, RNA stability measurements, and translatome profiling. Such integration can transform controlled-environment Solanaceae research from descriptive stress omics to predictive, mechanism-based crop management.

Fish muscle deteriorates rapidly after harvest because its polyunsaturated lipid-rich membranes, endogenous enzymes, nitrogenous substrates, and hydrated protein matrix remain chemically and microbiologically active. Lipid hydrolysis and oxidation, protein modification, nucleotide degradation, microbial metabolism, and volatile release therefore proceed as interconnected pathways. This review develops a precursor-product-perception framework for integrating lipidomics and flavoromics in fish-quality research. It examines phospholipid remodeling, free-fatty-acid release, hydroperoxide formation and decomposition, reactive carbonyl generation, protein carbonylation, and lipid-protein interactions, together with their roles in forming aldehydes, alcohols, ketones, furans, sulfur compounds, nitrogenous volatiles, and organic acids. The effects of chilling, freezing, freeze-thaw abuse, salting, drying, smoking, thermal processing, packaging, and emerging preservation technologies are evaluated in relation to molecular precursors, microbial activity, protein structure, volatile profiles, and sensory quality. Analytical strategies based on LC-MS lipidomics, GC-MS and GC-IMS flavoromics, microbiomics, protein-oxidation markers, sensory analysis, and chemometrics are compared for biomarker discovery. The review emphasizes that simultaneous measurement alone does not constitute true integration; robust biomarkers require paired sampling, mechanistic precursor-product evidence, targeted confirmation, odor-activity assessment, and external validation across species and storage conditions. This framework supports reliable freshness indicators and mechanism-based quality control for fish and fishery products throughout complex post-harvest commercial supply chains worldwide.

The decision by the co-Editor-in-Chief of Regulatory Toxicology and Pharmacology, Prof. Martin van den Berg, to retract the 2000 review article by Williams, Kroes, and Munro has elicited widespread criticism within the scientific community. Issued in late 2025, the retraction decision cites procedural concerns including potential ghostwriting, undisclosed conflicts of interest, and omission of certain unpublished studies, invoking Committee on Publication Ethics guidelines despite lacking evidence of fraud or scientific flaws. This editorial argues that the retraction decision involves editorial overreach and misapplication of the guidelines. The alleged omissions stemmed from proprietary data access limitations that were disclosed in the original paper. Subsequent reviews by several independent expert panels and regulatory authorities with access to all glyphosate data, including the studies cited by the retracting editor, reached similar conclusions. Claims of ghostwriting were previously investigated and found lacking, including a declaration by EFSA as to the clarity of the conflict disclosures. The retraction's timing, reliance on litigation documents, and apparent biases that were not disclosed in the retraction notice raise questions of ideological interference. Absent substantive rebuttals based on scientific merit rather than speculative claims of inappropriate authorship and data access, this retraction decision sets a dangerous precedent for retroactive censorship, potentially chilling beneficial industry-academic collaborations and eroding trust in the integrity of scientific publishing. With the strongest conviction, we assert that retracting a paper without scientific flaws isn't protection-it is censorship. We therefore call for the immediate reversal of this flawed and unjustified retraction to preserve trust in peer-reviewed literature.

This study evaluated prevalence, productive losses, and spatial distribution of cases in cattle slaughtered under the Federal Inspection Service (SIF) in Minas Gerais (2021-2022). A total of 297,802 animals were inspected; cysticercosis was detected in 0.44% (531/120,011) of cattle in 2021 and 0.24% (419/177,791) in 2022. Detection led to immediate condemnation of viscera, reducing carcass value by about 10%, and to conditional utilization of 37.1% (352/950) of carcasses by chilling and 15.8% (150/950) by heat treatment, with value reductions of 30% and 70%, respectively. Cysticerci were mainly located in the heart (45.2%), liver (40.1%), and head (21.2%), with rare occurrences in the tongue, diaphragm, and lungs. Estimated losses over two years exceeded R$ 900,000, likely underestimated given that SIF slaughter often supplies export markets. Spatial distribution analysis showed a higher concentration of positive animals originating from the municipalities of Nanuque, Governador Valadares, and Carlos Chagas. Despite the relatively low prevalence, the spatial concentration of cases and the observed distribution pattern suggest the influence of regional environmental factors in maintaining bovine cysticercosis transmission.

Lignin deposition in fruit trees represents a fundamental physiological trade-off: essential for structural integrity and stress adaptation, yet excessive or mistimed activation compromises fruit texture, palatability, and market value. This review synthesizes advances in lignin biosynthesis and its multilayered regulation in commercial fruit species. We describe how abiotic (drought, salinity, temperature extremes) and biotic (pathogens, pests) stresses trigger lignification through transcriptional, post-transcriptional, hormonal, and epigenetic mechanisms, centered on the conserved NAC-MYB cascade. This core module integrates WRKY/ERF transcription factors (TFs), microRNA networks, and hormone signaling. Transcriptional programs are further refined by microRNAs, alternative splicing, DNA methylation, histone acetylation, and phytohormone crosstalk (abscisic acid, ABA; jasmonic acid, JA; salicylic acid, SA; and brassinosteroids, BRs). We emphasize molecular crosstalk integrating abiotic and biotic stress signaling via shared TFs, reactive oxygen species (ROS), and epigenetic memory. We critically examine lignification's dual nature during development and postharvest storage, contributing to desirable traits (stone formation and skin toughness) but also driving defects (stone cell gritty texture and chilling-induced wooliness). Finally, we propose a strategic framework leveraging molecular breeding, targeted gene editing, and precision horticulture to fine-tune lignification, enabling climate-resilient cultivars without compromising fruit quality.

Vitis vinifera is a fruit tree species of great economic value worldwide. Nevertheless, chilling injury induced by cold stress restricts its yield and hinders the development of the grape industry. Based on previous findings of our research group that exogenous trehalose enhances abiotic stress tolerance in grape callus, this study adopted physiological, transcriptomic and metabolomic approaches to explore the potential regulatory relationships associated with exogenous trehalose. In this study, trehalose treatment alleviated chilling injury under 12 °C cold stress and increased the fresh weight of Vitis vinifera 'Thompson Seedless' callus. Meanwhile, trehalose application significantly elevated endogenous trehalose and soluble sugar content in grape callus, accompanied by increased activities of POD, SOD, and CAT, as well as reduced levels of MDA and O₂•⁻. KEGG enrichment analysis of transcriptomic data revealed that DEGs were mainly enriched in pathways related to biosynthesis of secondary metabolites, plant hormone signal transduction, starch and sucrose metabolism, and the MAPK signaling pathway in plants. Key DEGs included BAMS, STS, IAA, RLKs, and BGLU, while differentially expressed transcription factors were predominantly distributed in the AP2/ERF-ERF and MYB families. WGCNA identified the brown and turquoise modules as modules putatively correlated with physiological traits in grape callus, from which candidate genes potentially involved in trehalose-mediated cold response, including VQ22, RGLG2, PPR21, CML16, and SPL6, were screened. Combined transcriptomic and metabolomic analysis showed that DEGs and DAMs were jointly notably altered in the metabolic pathways of flavonoids, benzenes and their substituted derivatives, alkanolamines, terpenoids, and alkaloids. Moreover, all DAM-interacting genes identified were DEGs from the transcriptome. RT-qPCR analysis confirmed that the expression patterns of the selected cold-responsive genes were reliable and consistent with the transcriptomic results. Using integrated physiological, transcriptomic and metabolomic approaches, we identified candidate modules and genes related to cold tolerance in grape callus, as well as physiological responses and potential pathways underlying trehalose-mediated cold tolerance. We also characterized candidate genes involved in this regulatory process, providing a theoretical reference for exploring cold tolerance mechanisms in grape callus.