Search Results (106)

The successful use of Assisted Reproductive Technologies (ARTs) such as artificial insemination (AI) in small ruminants and other mammals depends on many factors, the most important of which is the quality of the semen used. The liquid storage and cryopreservation of spermatozoa at lower temperatures are associated with artificial insemination and rapid genetic improvement programs in the sheep production industry. Several studies have reported increased lipid peroxidation (LPO) and highly reactive oxygen species (ROS) production during liquid storage or cryopreservation of ram semen, leading to oxidative stress (OS), decreased antioxidant defense, and changes in sperm quality parameters like biokinetic and biochemical characteristics, viability, functional membrane and DNA integrity, along with mitochondrial activity. Therefore, supplementing ram semen extenders with exogenous antioxidants before preservation could mitigate this harmful effect. Various in vitro studies have reported improvements in ram sperm quality parameters like motility indexes, vitality, functional membrane/DNA integrity, antioxidant enzyme activity, total antioxidant content, mitochondrial activity, in vivo/in vitro fertility with significant decline in sperm abnormality, free radical production, LPO, ROS, apoptosis rate, and cytochrome C release from the mitochondrial matrix after the addition of various natural and synthetic antioxidant (vitamins, glutathione, taurine, pyruvate, melatonin, cysteine, selenium, zinc, plant extracts, sugars, amino acids, polyphenols) substances during preservation. Therefore, this review summarizes recent findings on oxidative stress-induced damage to sperm quality parameters in various ram breeds during chilling storage and cryopreservation. Moreover, supplementing basic semen extenders with different non-enzymatic antioxidant substances as a method to maintain sperm quality—along with their efficacy in reducing or preventing sperm damage during preservation—was discussed in detail. Full article

Xishuangbanna (XIS) cucumber (Cucumis sativus) originated from low-altitude southwest China and shows extreme cold sensitivity. Nano-hydroxyapatite (nHAP), known for its high bioavailability and surface reactivity relative to bulk HAP, was applied to enhance the cold tolerance of XIS seedlings. We optimized fertilization timing and fertilizer concentration. By determining physiological parameters alongside gene expression profiling and transcriptomic analysis, we preliminarily dissected the physiological and molecular mechanisms underlying nHAP-enhanced chilling tolerance. nHAP application preserved free and bound water even at 24 h into the cold-stress treatment, as detected by nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI). Exposure to cold stress caused a chilling injury index (CII) of 73.33%, while foliar spraying of nHAP at gradient concentration reduced CII values by 9.09–54.55%. At the same time, electrolyte leakage and malondialdehyde content were decreased by 6.68–61.41% and 12.92–67.16% respectively; chlorophyll content increased by 0.01–73.42%; SOD, POD, and soluble protein content increased by 10.54–161.53%, 16.50–154.33%, and 2.03–63.26%, respectively. Soil application of nHAP showed a similar but weaker effect than foliar spraying on alleviating chilling injury, and the optimal concentration was 1000 mg/L. Quantitative Real-Time PCR (qRT-PCR) revealed that foliar spraying of nHAP upregulated the gene expression of Superoxide dismutase genes (CsCu/ZnSOD and CsMnSOD) and major facility superfamily genes (CsSPX-MFS1 and CsSPX-MFS2) in the cold treatment. We then profiled the transcriptome changes in seedling leaves during the cold treatment after foliar spraying of nHAP. Without nHAP application, cold stress resulted in a total of 6795 differentially expressed genes (DEGs), which were functionally enriched in plant–pathogen interaction and plant hormone signal transduction pathways. Under nHAP application, cold stress only caused 776 DEGs, which were functionally enriched in plant hormone signal transduction and galactose metabolism. These findings suggest that nHAP could improve the cold tolerance of cucumber seedlings through boosting antioxidant activity and plant hormone signaling pathways. Full article

Winter underuse of urban parks in severe-cold cities limits year-round outdoor activity, especially for cold-sensitive users. This study developed a comfort–risk–adaptation framework integrating thermal perception, model-estimated cold-stress risk, and behavioral responses. Field microclimate measurements and synchronous questionnaires were conducted in Nanhu Park, Changchun, China, under clear winter conditions, yielding 386 paired human–environment samples. The Universal Thermal Climate Index (UTCI), Required Clothing Insulation (IREQ), wind chill temperature (WCT), and contact cooling indicators were used to quantify thermal exposure and cold-stress risk. Results showed significant spatial differences in wind speed, solar radiation, mean radiant temperature, and UTCI, while air temperature and humidity varied little. The neutral UTCI was 3.14 °C (unweighted) and 3.70 °C (weighted), and the 80% thermal acceptability threshold was −15.24 °C (95% CI: −16.14 to −14.22 °C). Despite acceptable thermal perception, physiological cold-stress risks remained under certain conditions. The findings highlight the need to integrate solar access, wind mitigation, low-conductivity materials, and moderate activity routes to improve winter usability in severe-cold urban parks. Results are condition-specific and reflect observed users under clear to partly cloudy winter daytime conditions rather than universal thresholds. Full article

Browning and microbial spoilage are major constraints on the shelf-life of fresh-cut potatoes, yet the concentration-dependent effects of sodium metabisulfite (SM) on product quality and bacterial dynamics are poorly understood. In this study, the impact of SM on the quality and bacterial dynamics of fresh-cut potatoes during storage was investigated. This study evaluated the concentration-dependent effects of SM on the quality of fresh-cut potatoes. The results showed that 0.3% SM treatment effectively delayed browning. Subsequently, the quality and bacterial community of fresh-cut potatoes of CK and 0.3% SM-treated groups were further investigated. The results indicated that a 0.3% SM treatment could inhibit the activities of polyphenol oxidase (PPO), peroxidase (POD) and phenylalanine ammonia-lyase (PAL) as well as the growth of Duganella. On day 7 of storage, the L* values of the control group (CK) and 0.3% SM groups decreased by 17.02% and 7.68%, respectively, while their total plate counts were 4.33 and 4.21 log CFU/g, showing a significant difference between the two groups (p < 0.05). Furthermore, SM treatment extended the shelf-life of fresh-cut potatoes to approximately 7 days, decreased the loss of soluble solids and weight, and maintained textural characteristics (firmness and elasticity). These findings demonstrate that SM treatment is an effective strategy for preserving the quality of fresh-cut potatoes and provide new insights into its role in inhibiting enzymatic browning during storage. Full article

Chilling injury is a major problem limiting the postharvest storage and marketability of mango fruit at low temperature. The present study investigated the individual and combined effects of sodium nitroprusside (SNP), L-arginine (Arg) and salicylic acid (SA) on chilling tolerance, regulation of oxidative stress and the postharvest quality of ‘Keitt’ mango fruit stored at 5 ± 1 °C for 28 days followed by 4 days of shelf life at 23 °C. Fruits were pre-treated with 1 mM SNP, 1 mM Arg, 2 mM SA or their binary combinations before storage. The chilling injury, membrane damage, lipid peroxidation, protein oxidation and fruit softening were greatly enhanced by cold storage in untreated fruits. In contrast, all the treatments significantly ameliorated these deteriorative changes, and the combined treatments were superiorly effective. Among these, SNP + Arg was the most effective treatment, which reduced the chilling injury index from 4.05 in control fruits to 1.00 after shelf life, completely inhibiting the incidence of decay and reducing electrolyte leakage and malondialdehyde accumulation by 47.4 and 48.2%, respectively. The same treatment also maintained higher firmness, titratable acidity, visual appearance and ascorbic acid content than untreated fruits. The enhanced chilling tolerance was accompanied by increased antioxidant defense, as SNP + Arg significantly stimulated the activities of superoxide dismutase, catalase and peroxidase, but suppressed the activity of pectin methylesterase. Multivariate analyses, such as PCA, clustered heatmap and integrated stress index, demonstrated a strong negative relationship between oxidative stress markers and antioxidant metabolism. The results showed that combined SNP and Arg treatments enhanced chilling tolerance through increasing antioxidant capacity, preserving membrane integrity, and retarding ripening-related metabolism, which provides an effective way to maintain the postharvest quality of cold-stored mango fruit. Full article

Eggplant (Solanum melongena L.) is highly susceptible to chilling injury (CI) during cold storage, with severity being strongly influenced by fruit maturity stage. At the tissue level, the peel acts as the primary site of cold-stress metabolic responses. This study evaluated the effect of pre-storage glycine betaine treatment (GB, 10 mM) on CI in purple eggplant at baby (BB, low sensitivity) and commercial (CC, high sensitivity) maturity stages stored at 4 °C for 20 days, integrating the use of ATR-FTIR spectroscopy as a rapid, non-destructive tool to monitor quality in the fruit peel. Physiological traits including chilling injury index (CII) and fruit rigidity were integrated with peel-specific ATR-FTIR spectroscopy combined with chemometric analysis to describe structural and metabolic behavior. BB fruit showed higher tolerance to CI, reaching a CII 23% lower than CC after 20 d, along with greater rigidity retention. GB treatment was significantly effective in reducing CI in both maturity stages by decreasing CII by 23% for BB and 32% for CC fruit, and delaying symptom onset. FTIR analysis revealed that the main peel spectral changes during storage occurred in the amide–phenolic (1653–1515 cm⁻¹) and polysaccharide (~1017 cm⁻¹) regions. Control fruit showed progressive shifts in these regions indicating structural disorganization, while GB-treated fruit delayed and attenuated spectral changes. Chemometric analysis (OPLS-DA) clearly discriminated samples according to maturity stage, treatment, and storage time. Overall, the results demonstrate that chilling susceptibility is determined by maturity stage, that the GB treatment enhanced CI tolerance—especially in sensitive CC fruit—and that ATR-FTIR coupled with chemometrics provides an effective approach for rapid non-destructive monitoring of postharvest quality changes in eggplant during cold storage. Full article

Ice adhesion on exposed structures remains a major operational challenge, motivating the search for passive, material-based anti-icing strategies. Molecular dynamics offers a controlled way to investigate ice–surface interactions beyond the limits of experimental setups. In this work, we develop a simulation framework to model the impact of solid hexagonal ice droplets on metallic substrates. Ice impacts are simulated across a range of velocities (10–120 m/s), temperatures (120–250 K), and face-centred cubic surface materials (gold, copper, silver, aluminum, and nickel). Using LAMMPS, mW water force-field, EAM/Alloy metal potentials, and Lennard-Jones water–surface interactions, we quantify phase evolution through angular order parameter and quasi-liquid layer measurements, complemented by the CHILL+ algorithm in OVITO. By isolating all external factors, we show that melting increases with velocity and temperature and correlates with substrate properties: metals with high thermal diffusivity and low Young’s modulus tend to decrease post-collision ice melting. The ratio of the former to the latter, a derived index of merit Υ, significantly correlates with melting percentage and identifies silver as the most effective anti-ice material examined. Statistical analyses strongly suggest that these surface properties influence interfacial melting, supporting the use of this modelling framework for screening and designing anti-icing materials. Full article

Low-temperature stress adversely impairs rice germination and seedling establishment. This study assessed a nano-bio-priming strategy using lecithin (L) and silicon dioxide nanoparticles (SiO₂ NPs) to enhance chilling tolerance. Two fragrant rice cultivars (Xiangyaxiangzhan and Meixiangzhan 2) were primed with six combinations of lecithin (0, 50, and 100 μmol·L⁻¹, denoted as L0, L1, and L2) and SiO₂ NPs (0 and 100 mg·L⁻¹, denoted as S0 and S1) and exposed to optimal temperature (25 °C) or low-temperature stress (15 °C). Low-temperature stress delayed germination onset by two days. Combined priming treatments L1S1 and L2S1 significantly alleviated this inhibitory effect. Crucially, cultivar-specific responses were evident in Meixiangzhan 2, where L1S1 increased the germination vigor index by 50.97%. Meanwhile, the effect was less pronounced or inhibitory at normal temperature in Xiangyaxiangzhan. Priming substantially enhanced seedling growth, and L2S1 maximally increased root and shoot length in Meixiangzhan 2 by 55.30% and 15.82%, respectively. Furthermore, biomass accumulation was strongly promoted. L1S1 increased total dry weight and total fresh weight in Meixiangzhan 2 by 19.64% and 23.48%, respectively. Physiologically, priming elevated chlorophyll and carotenoid contents upregulated the activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), and increased levels of soluble protein and ascorbate (AsA), while maintaining nitrate reductase (NR) activity and hydrogen peroxide (H₂O₂) homeostasis. These physiological improvements were positively correlated with enhanced growth. Our findings demonstrate that co-priming with lecithin and SiO₂ NPs is a potent strategy for enhancing low-temperature tolerance, with efficacy depending on both the treatment combination and rice genotype. Full article

Moist chilling is widely used to overcome seed dormancy in zoysiagrass (Zoysia japonica Steud.), but the coordinated physiological and molecular basis remains unclear. Here, freshly matured seeds were subjected to moist chilling at 4 °C in darkness for 0 (Control), 1 (CS1), 2 (CS2), 3 (CS3), or 4 weeks (CS4) and then transferred to germination conditions (30/20 °C, day/night). Prolonged moist chilling progressively improved dormancy release: final germination percentage increased from 40.5% (Control) to 73.5% (CS4), accompanied by a higher germination index and earlier, faster cumulative germination dynamics. Moist chilling also enhanced early seedling vigor, with stronger treatment differentiation in root elongation than in shoot growth. Physiologically, abscisic acid (ABA) content declined while gibberellic acid (GA) content increased, resulting in an elevated GA/ABA ratio with prolonged chilling. Metabolic activation was evidenced by increased α-amylase activity, greater soluble sugar and soluble protein accumulation, and stimulated oxygen uptake. In addition, CAT, SOD, and POD activities were enhanced under prolonged moist chilling, whereas H₂O₂ levels remained relatively stable, suggesting that redox adjustment during dormancy release was characterized by strengthened antioxidant buffering rather than pronounced oxidative accumulation. qRT-PCR supported a mechanistic transition from dormancy maintenance to germination execution, showing moist chilling-associated regulation of ABA/GA metabolism and signaling genes (e.g., NCED, CYP707A, ABI3/ABI5, and GA20ox) and downstream metabolic modules (e.g., GAMYB, AMY, ISA, INV, and HXK1), together with concurrent modulation of respiration- and ROS-related markers (e.g., AOX1a, RBOH, and CAT). Correlation analysis linked germination performance most strongly with α-amylase activity, oxygen uptake, and the GA/ABA ratio. Collectively, our data support a working model in which moist chilling rebalances the ABA–GA gate and activates downstream metabolic and redox adjustment modules to promote dormancy release and improve germination performance in zoysiagrass, providing practical markers for optimizing seed establishment through moist chilling treatment. Full article

High-altitude grazing animals are continuously exposed to strong wind and low temperature, which challenge physiological homeostasis and energy metabolism. Improving living conditions and nutritional supplementation are two commonly used strategies. In this study, sixty 7-month-old Gangba sheep (initial body weight (BW) 21.00 ± 1.90 kg) were allocated to a 42-day trial with four groups (open-air sheepfold, mobile sheepfold, open-air sheepfold + supplementary feeding, mobile sheepfold + supplementary feeding) to investigate their effects on growth performance, serum parameters and gut microbiota in naturally grazing Gangba sheep. Mobile sheepfolds increased the temperature–humidity index (THI) and reducing the wind chill index (WCI) (p < 0.05). The sheep with mobile sheepfold showed higher serum total antioxidant capacity and lower levels of heat shock proteins HSP70 and HSP90 (p < 0.05), indicating alleviated stress. Supplementary feeding markedly increased final BW and average daily gain (p < 0.05). The interaction between sheepfold type and feeding supplementation showed increasing IgA levels in the open-air sheepfold with supplementary feeding group and increasing IL-4 levels in the mobile sheepfold with supplementary feeding group, while TNF-α concentrations were reduced in all three treatment groups (p < 0.05). Meanwhile, KB and FFAs were increased in the open-air sheepfold with supplementary feeding group but decreased in the mobile sheepfold with supplementary feeding group (p < 0.05). The mobile sheepfold also increased the Bacillota-to-Bacteroidota ratio, suggesting improved microbial community structure. Functional predictions showed enrichment of reductive acetogenesis and reduction in aerobic chemoheterotrophy and sulfur-related respiration pathways (p < 0.05). Moreover, key microbial genera were significantly correlated with THI and WCI (p < 0.05). Collectively, these results demonstrated that mobile sheepfold together with feeding supplementation improve stress responses, serum immune and lipid metabolic indicators, and potentially altered gut microbial composition and function, providing insights into host–microbiota interaction in extreme high-altitude environments. Full article

Blueberries (Vaccinium spp.) are highly sensitive to winter chilling fulfillment, growing degree days above 7 °C (GDD7), and water balance (WB). By integrating a climate-based natural suitability index (CNSI), three-dimensional kernel density estimation, traditional and spatial Markov chains, and optimal geographic detector analysis, this study examines the spatiotemporal evolution and driving mechanisms of blueberry climatic suitability realization in 19 major producing provinces in China during 2008–2023. Results show that CNSI exhibits a stable and moderately right-skewed distribution, with partial convergence and a narrowing interprovincial gap. Suitability realization is highest in the middle and lower Yangtze River rice-growing belt, whereas the northern dryland belt and the southern subtropical mountainous belt show persistent mismatches between climatic potential and production advantages. Markov results reveal path dependence and moderate mobility, with “low–low lock-in” and “high–high club” phenomena reinforced under neighborhood effects. GeoDetector results indicate that effective facility irrigation and fertilizer input are dominant factors explaining spatial variation in CNSI, while comprehensive transportation accessibility and agricultural labor act as stable complements. Interaction analysis suggests that multi-factor synergies, particularly irrigation-centered combinations, yield strong dual-factor enhancement and near-nonlinear enhancement. These findings highlight the importance of aligning climatic suitability with adaptive infrastructure investment and region-specific management to promote sustainable production-share advantages in China’s blueberry industry. Full article

As cold-sensitive fruits, loquats easily develop chilling injury (CI) during cold storage, which leads to quality deterioration and economic losses. Our prior research indicated that exogenous melatonin (MT) treatment can mitigate CI in postharvest loquats by regulating reactive oxygen species (ROS) metabolism, but the underlying molecular mechanism remains unclear. The primary objective of this study is to decipher the molecular regulatory pathway by which MT alleviates CI in postharvest loquats, focusing on the role of MYB transcription factors (TFs) in modulating antioxidant enzyme genes. Here, MT treatment remarkably reduced CI severity in loquat fruits, as reflected by lower CI index, reduced cell membrane permeability, decreased firmness, lower a* and b* values, and higher L* value, compared with the control group. Moreover, a cold-induced MYB TF, designated EjMYB15, was identified. Compared to non-treated fruits, the expression level of EjMYB15 was maintained at higher levels in MT-treated loquats. Subcellular localization and transactivation assays demonstrated that EjMYB15 is a nuclear-localized transcriptional activator. Electrophoretic mobility shift assay (EMSA) and dual-luciferase reporter (DLR) assays showed that EjMYB15 binds the MYB-binding sites (MBS) in the promoters of four antioxidant enzyme genes (EjCAT1, EjCAT2, EjGST1, and EjGST2), thereby activating their transcription. Taken together, these findings indicate that EjMYB15 positively regulates cold tolerance of loquat fruits by improving ROS scavenging capacity. These results elucidate the regulatory pathway by which MYB TFs mitigate CI and provide new theoretical support for the application of MT in alleviating CI in postharvest fruits. Full article

This study aimed to determine the degree of diversification in exports of fresh/chilled salmon and the level of international competitiveness of Norway, Sweden, Chile, and the United Kingdom over 2020–2024, using the Herfindahl–Hirschman Index (HHI) and the normalized revealed comparative advantage (NRCA). A quantitative, descriptive approach was adopted, drawing on annual Trade Map data for HS subheading 030214. HHI series were constructed by country–destination and NRCA series by country–market, and both were examined through univariate analysis. The findings showed that Norway exhibited low concentration levels and strong, stable advantages in Saudi Arabia, Türkiye, and Russia, whereas Sweden displayed moderate but rising concentration, supported by high advantages in Belgium, the United Kingdom, Germany, and Italy. In contrast, Chile and the United Kingdom recorded persistently high HHI values, with pronounced advantages concentrated in a limited number of markets (Brazil in Chile’s case; France and Chinese Taipei in the UK’s) and intra-product positions or comparative disadvantages in China, the United States, and Mexico. The study concludes that the combination of geographic diversification and positive NRCA enhances export resilience, while extreme specialization increases vulnerability to demand and regulatory shocks. It is recommended that Chile and the United Kingdom further develop diversification strategies toward markets where NRCA is neutral or negative, and that Norway and Sweden consolidate their advantages through investments in sustainability, traceability, and logistics. Further multivariate research incorporating macroeconomic and firm-level variables is also suggested. Full article

When kept at a low temperature, yellow melons are prone to chilling injury. It is widely known that applying putrescine (Put) after harvest can prevent chilling harm in fruit. The best dosage of Put for treating yellow melon remains unknown, and the underlying mechanisms are not well understood. This study aimed to investigate the effects of exogenous putrescine application on chilling injury in melons and to elucidate the underlying physiological and molecular mechanisms involved. In this study, melons were treated with various concentrations of Put (0, 1, 2, and 4 mM), and the phenotype, chilling injury index, endogenous polyamine content, activities of crucial enzymes, and expression levels of associated genes (CmADC, CmODC, CmSAMDC1-4, CmSPDS1-2, CmSPMS1-2, and CmCBF1-4) were measured during storage. In our study on yellow melon, we found that treatment with 2 mM Put optimally alleviated chilling injury. This effect was achieved by enhancing the activities of ADC, AIH, CPA, ODC, SAMDC, DAP, and PAO, thereby regulating the endogenous levels of Put, Spd, and Spm. Furthermore, Put mainly impacted the expression of CmCBFs, which might help regulate downstream cold-inducible genes, leading to the improvement of tolerance in yellow melon fruit. Exogenous Put enhances melon chilling tolerance by activating endogenous polyamine biosynthesis and the CBF signaling pathway. This provides an effective strategy for post-harvest preservation of melons and might serve as a guide for future research into the mechanism involved in Put-induced chilling tolerance in horticulture crops. Full article

In order to determine the heat and humidity conditions of Igloo-type calf hutches, both in open space and under verandas, an analysis was conducted of the impact of the location of the veranda within the premises of the farm and its orientation in relation to the cardinal compass points and prevailing wind speed, as well as temperature and relative atmospheric humidity. The analysis was conducted based on constant measurement (temperature, relative humidity, air velocity) for climate conditions under the veranda and in the areas between the farm buildings. The 432,432 data points obtained in this way were used for further calculations and analysis of WCT (Wind Chill Temperature) and WCI (Wind Chill Index). Studies have shown that placing the hutch under a shelter allows for more favorable thermal and humidity conditions by reducing wind speed, and consequently increasing the apparent temperature and limiting the rate of heat loss. The analysis has demonstrated that the selection of the location of the hutch or calf enclosure is crucial for calf welfare. It is recommended that environmental studies be conducted individually for farms raising calves, especially dairy cattle breeds. An optimal location and utilisation of existing infrastructure will reduce the financial outlays for implementing new solutions. This analysis, conducted in Eastern Europe, also provides a basis for inferring the impact of climate change on local microclimatic conditions. Full article