Search Results (188)

Global crop production faces serious threats from soil salinization. Microbial resources are often exploited to be used as fertilizers or seed coatings to address this issue. Parametarhizium changbaiense, as a novel beneficial microorganism, has been discovered to be capable of assisting limited crops such as mung bean in resisting salt–alkali stress. To investigate the effects of P. changbaiense on sugar beet under salt–alkali stress, the salt (NaCl:Na₂SO₄, molar ratio 9:1) and alkali (NaHCO₃:Na₂CO₃, molar ratio 9:1) stress were set on sugar beet germplasm 780016B. Results demonstrated that P. changbaiense improved the phenotypic characteristics of sugar beet seedlings under salt–alkali stress. The biomass parameters such as plant height and fresh weight significantly increased by growth-promoting effect. The elevated antioxidant enzyme activity could help protect plants from ROS damage induced by stress. Relative electrical conductivity and MDA content decreased with inoculation, thereby mitigating membrane lipid peroxidation and improving membrane system stability. The higher content of soluble sugar could maintain cell turgor pressure and alleviate osmotic stress. Inoculation with P. changbaiense enhanced chlorophyll content, fluorescence, and photosynthetic capacity. The more superior root vitality and architecture were suitable for the functions of metabolism and absorption. P. changbaiense could promote the growth and physiological characteristics under salt–alkali stress, so it has practical application value in agricultural production. Full article

Grazing is a pervasive disturbance in arid ecosystems, but its effects on community-level coordination of plant hydraulic and economic traits remain poorly understood. Here, we investigated how long-term grazing alters community-weighted mean hydraulic and leaf economic traits in a desert steppe of Inner Mongolia, and how these shifts affect aboveground biomass (AGB) and water-use efficiency (WUE). Grazing drove a coordinated conservative shift in community hydraulic traits, including more negative osmotic potential at turgor loss point (ψ_tlp), increased cell wall rigidity (ε), and reduced leaf hydraulic conductance (K_leaf). Grazing also restructured trait–function relationships: under grazing, AGB was positively correlated with dehydration tolerance rather than transport efficiency, and WUE was tightly coupled with osmotic adjustment. Variance partitioning showed that hydraulic traits explained 57.4% of AGB variation under grazing, whereas economic traits dominated in the control site (74.5%). Our findings demonstrate that long-term grazing imposes a fundamental reorganization of community-level trait coordination, driving a transition from an efficiency-oriented to a safety-oriented strategy, and highlight the central role of hydraulic traits in mediating ecosystem function under combined stress. Full article

Histone demethylases regulate epigenetic modifications and DNA damage repair in fungal pathogens, yet their specific functions in Magnaporthe oryzae remain poorly understood. This study identifies MoRph1, a JmjC domain-containing histone demethylase that interacts with the COMPASS complex. Targeted deletion of MoRph1 resulted in significantly reduced vegetative growth, impaired conidiation, and defective appressorium formation. The mutant displayed compromised appressorial turgor pressure due to delayed degradation of glycogen and lipid reserves, leading to inefficient host penetration and attenuated virulence on rice and barley. MoRph1 localized to the nucleus, and its absence caused increased nuclear abnormalities under DNA damage stress, suggesting impaired genome stability maintenance. Biochemical analysis confirmed that MoRph1 specifically demethylates histone H3 lysine 36 trimethylation. Transcriptome analysis revealed altered expression of genes associated with DNA replication, mismatch repair, and oxidative stress response. These results establish MoRph1 as a crucial epigenetic regulator coordinating fungal development, infection structure function, energy mobilization, and DNA damage repair. This study underscores the importance of chromatin-level regulation in fungal pathogenicity and provides a foundation for future evaluation of MoRph1 as a potential antifungal target. Full article

Frequent co-occurrences of high temperature and drought in tropical regions make heat and drought tolerance of landscape plants core physiological traits that determine their landscape adaptability and community stability. However, systematic elucidation of the differentiation patterns of stress resistance between specialist and generalist tropical landscape plant species, the intrinsic correlations between heat and drought tolerance traits, and the regulatory mechanisms of leaf functional traits remains lacking. In this study, eight typical tropical landscape plant species in Xishuangbanna Tropical Botanical Garden were selected as research objects. By determining leaf chlorophyll fluorescence parameters, water relation parameters and leaf functional traits, we systematically analyzed the differences in heat and drought tolerance and interspecific differentiation characteristics between specialist and generalist species, and simultaneously elucidated the correlation patterns of drought-heat tolerance traits as well as the regulatory effects of leaf functional traits on these traits. The results showed that the turgor loss point water potential (Ψ_TLP) of generalist tropical landscape plant species was significantly higher than that of specialist species, with superior drought tolerance; in contrast, the half-lethal temperature of photosystem II (T50) of specialist species was significantly higher than that of generalist species, with stronger heat tolerance. Among the eight tested species, Bombax ceiba exhibited the strongest drought tolerance, while Baccaurea ramiflora had the optimal heat tolerance. The study also found that the drought and heat tolerance traits of tropical landscape plants exhibited stress-specific trade-offs; leaf functional traits had limited overall explanatory power for the stress resistance of tropical landscape plants and only exerted a certain regulatory effect on drought tolerance. This study clearly reveals the differences in heat and drought tolerance between specialist and generalist species. This finding not only enhances our mechanistic understanding of stress resistance in tropical plants but also provides data support for ecological restoration and conservation practices in tropical gardens. Full article

Barley lodging—specifically stem lodging—occurs when the bending moments from wind and ear weight exceed the culm’s load-bearing capacity. Lodging risk decreases as plant height decreases and culm strength increases. Geometry (stem diameter, culm wall thickness) and material strength determine culm bending strength. By studying changes in stem mechanical properties (at three positions along the culm) in two genotypes (grown in a greenhouse), we found that culm strength (assessed with a three-point bending test) slightly diminished through ripening owing to a decline in both area moment of inertia (i.e., strength due to geometry alone) and apparent material strength, presumably due to turgor loss. When the stem segments collected from fully ripe plants were dried to a moisture content typical of harvest maturity, however, strength rose to a maximum. Thus, minimum stem bending resistance occurs during a window in which plants are fully ripe but have not yet reached harvest-dry moisture content. Hence, in the absence of rain—which would severely reduce the mechanical strength of dry, ripe plants—the physiological risk of stem lodging is highest when the crop is fully ripe but not yet harvest-dry. However, the actual lodging risk increases as harvest approaches, because summer storms are frequent at this time of year and dry straw loses rigidity when wetted. Full article

Castanea henryi is one of the important fruit tree species cultivated in the mountainous regions of China. Castanea henryi is a starch-accumulating type. As an intracellular substance, starch plays an important role in maintaining cell turgor and sustaining fruit firmness. Although starch metabolism has been extensively studied in model and fruit crops, its regulatory mechanisms in Castanea henryi remain poorly understood. This review synthesizes recent advances in starch physicochemical properties, metabolic pathways, and regulatory mechanisms during fruit development, seed germination, and postharvest storage. Current knowledge gaps, including limited molecular characterization and gene functional analysis in Castanea henryi, are highlighted. This review provides a framework for future research and breeding strategies aimed at improving fruit quality and storage performance. Full article

Liquidambar formosana Hance, a tree species in subtropical broad-leaved forests, exhibits a striking autumn leaf coloration. However, how drought stress during this period influences leaf color change remains poorly understood. In this study, two-year-old seedlings were subjected to four drought gradients. Leaf color parameters, pigment contents, cellular structure, photosynthetic physiology, and hydraulic properties were systematically measured throughout the leaf color transition period. The results show that, with increasing drought severity, leaf red-green coordinate a* increased significantly during early-to-middle stress (S1–S3), while lightness L* and yellow-blue coordinate b* increased at late stress (S4). Chlorophyll (Chl) content continuously decreased, anthocyanins (Ant) peaked at mid-stress, and carotenoids (Car) became enriched at late stress. Leaf cellular structure and hydraulic parameters declined, photosynthetic function was inhibited, and antioxidant enzyme activities showed an initial increase followed by a decrease. Correlation analysis and Random Forest models revealed that L* was strongly associated with superoxide dismutase (SOD) activity, carotenoid-to-chlorophyll (Car/Chl) ratio, and net photosynthetic rate (P_n); a* was closely linked to osmotic potential at full saturation (Ψ_sat), relative water content at the turgor loss point (RWCtlp), SOD activity, Car/Chl ratio, anthocyanin-to-chlorophyll (Ant/Chl) ratio, Ant content, transpiration rate (T_r), P_n, and main vein thickness (Mvt), while b* was primarily correlated with Ψ_sat, Car/Chl ratio, SOD activity, Ant/Chl ratio, and P_n. These statistical associations suggest multiple physiological processes are involved in leaf color change. Based on these findings, we propose a hypothetical sequence: drought initially disrupts leaf water status, leading to structural atrophy and hydraulic decline, followed by photosynthetic inhibition, activated antioxidant defense, and altered pigment accumulation, which are correlated with the sequential leaf color transition from green to red to yellow-orange in this species. Full article

Corolla movement is a typical plant movement behavior that enables plants to optimize pollination and adapt to environmental changes. Nevertheless, its molecular mechanism remains poorly understood. In the present study, we conduct a comprehensive transcriptome analysis of Mirabilis jalapa (Nyctaginaceae) corolla at five stages (AG-EG) to elucidate the regulatory networks underlying movement. The results showed that the differentially expressed genes (DEGs) were mainly associated with cellular processes, catalytic activity, MAPK signaling, plant hormone signal transduction, and photosynthesis-related pathways, highlighting their involvement in corolla dynamics. Transcriptome profiling further demonstrated that auxin, ethylene, and abscisic acid signaling pathways were key hormonal regulators of corolla movement. Moreover, Ca²⁺ transport genes (CNGCs and CMLs) and respiratory burst oxidase homologs (RBOHs) were significantly enriched, indicating that Ca²⁺–ROS signaling oscillations also play an important role in driving differential cell expansion and turgor changes. Transcription factor analysis also revealed the upregulation of WRKY2, WRKY22, and WRKY33, suggesting that WRKYs act as the critical transcriptional regulators linking ROS–Ca²⁺ signals with downstream gene expression. The reliability of RNA-Seq data was confirmed by RT-qPCR, which showed high consistency with transcriptome profiles. These findings suggested that corolla movement in M. jalapa is carried through the integration of hormonal pathways, Ca²⁺–ROS signaling, and WRKY-mediated transcriptional regulation. This research provided novel insights into the molecular basis of plant movement and established a foundation for further study on floral dynamics and adaptive strategies in angiosperms. Full article

Intergeneric hybridization of Vanda and Papilionanthe holds promise for pyramiding superior ornamental and stress-tolerant traits, though systematic studies on their hybrids remain scarce. Using Vanda lamellata var. Boxallii (♀), Papilionanda ‘Hetty Henderson’ (♂), and 72 progenies, we investigated parent–progeny relationships via iPBS markers, spectral phenomics, and morphology, alongside floral water balance and thermotolerance. Six iPBS primers amplified 90 bands (92.98% polymorphism), confirming high genetic diversity. Spectral reflectance (400–1000 nm) revealed organ-specific genetic differentiation. Clustering analyses consistently indicated that progenies were genetically and phenotypically closer to the female parent, with spectral/morphological patterns matching genetic groupings. Resistance evaluations showed progenies had significantly stronger floral water storage capacity than both parents, while the female parent excelled in water transport traits. Progenies developed thicker petal/sepal cuticles, though the male parent exhibited superior thermotolerance indices. This study clarifies the genetic regulation of stress resistance in these hybrids, providing critical support for precise early screening in orchid breeding. Full article

Soil salinity in wheat represents a severe threat to global productivity, requiring a deep understanding of physiological adaptation mechanisms to ensure food security in the context of continuous agricultural land degradation. The study aim was to assess the impact of a salinity gradient (0–75 mM NaCl) on the dynamics of stomatal opening and chlorophyll content of the varieties Glosa, Taisa, Boema and Granny. The methodology integrated four joint classes, of which two were from detailed physiological parameters, stomatal features and chlorophyll content, and two morphological characteristics, growth visual indices and biomass allocation. All data was corroborated into an original hierarchical synthesis model presented in a multi-layered sunburst plot. The most relevant results indicate that the concentration of 45 mM NaCl represents the osmotic adjustment threshold, where the active accumulation of ions decreases the internal osmotic potential, facilitating an influx of water that maximizes guard cell turgor and, implicitly, stomatal width. Maximal physiological parameters and biomass ranked the variety Granny first, followed by Taisa. Despite stomatal increases, Boema ranked third and Glosa showed overall decreased development and the lowest plant biomass. These findings validate the use of interconnected effects analysis as a screening tool for identifying the salinity responses of wheat varieties. Full article

Plant leaf drought tolerance is regulated by the coordinated effects of water transport efficiency, transpirational water loss, and hydraulic safety. Although cotton is considered drought-tolerant, the mechanisms that coordinate water transport and gas exchange to confer drought tolerance remain incompletely understood. In this study, four soil moisture gradients were established under field conditions and maintained consistently throughout the growing season. The relationships among leaf turgor loss point (Ψ_tlp), gas exchange, and hydraulic traits were examined in two cotton cultivars at the peak flowering stage. With increasing drought treatments, Ψ_tlp, stomatal aperture ratio (g_ratio), leaf hydraulic conductance (K_leaf), leaf hydraulic conductance inside the xylem (K_x) and leaf hydraulic conductance outside the xylem (K_ox) declined significantly, with K_x showing the greatest reduction. Both K_x and g_ratio were strongly positively correlated with Ψ_tlp. Anatomically, vein density (D_v) and vessel number (Np) increased, whereas xylem vessel area (Ap) decreased. The reduction in Ap was the primary structural factor driving the decline in K_x and contributing to lower Ψ_tlp. We conclude that cotton enhances drought tolerance through a coordinated hydraulic and osmotic strategy, by modifying xylem anatomy (reducing Ap) to downregulate K_x and by adjusting osmotically to depress Ψ_tlp. The synergistic reduction in K_x and g_ratio slows the decline in leaf water potential, thereby delaying Ψ_tlp and enhancing leaf hydraulic safety during drought. This integration optimizes stomatal regulation and water transport while ensuring hydraulic safety. The findings provide a key theoretical basis and potential breeding targets for the targeted improvement of drought tolerance and water use efficiency in cotton. Full article

Early recognition of vascular compromise is essential for reconstructive flap survival. In human surgery, local glucose monitoring is widely used as an objective indicator of perfusion, but its application in veterinary patients is still limited. This report describes postoperative glucose measurement as a simple and minimally invasive method for evaluating flap viability in two dogs. This report describes two prospectively observed clinical cases in which local glucose measurement was applied as an adjunctive monitoring tool during postoperative flap management. Local glucose values were measured with a handheld glucometer at predefined flap and control sites. Serial readings were compared with daily assessments of flap color, temperature, turgor, and wound integrity. A previously suggested threshold of 60–62 mg/dL was used as a reference for potential perfusion compromise. In Case 1, a phalangeal fillet flap showed a brief glucose decline on postoperative days 2–3, followed by normalization and uneventful healing. In Case 2, which underwent advancement flap reconstruction after wound dehiscence, glucose values remained persistently below 60 mg/dL and preceded visible ischemia and distal necrosis. Local glucose monitoring provided rapid and clinically meaningful information about flap perfusion. Transient decreases reflected reversible postoperative congestion, whereas persistent hypoglycemia indicated progressive ischemia. These findings support the use of glucose monitoring as an adjunct in small-animal reconstructive surgery. Full article

Soluble sugars are key determinants of fruit quality, directly influencing sensory attributes such as sweetness and flavor, as well as nutritional value and texture. Their content and composition are precisely regulated by sugar-metabolizing enzymes. Key enzymes, including invertase (INV), sucrose phosphate synthase (SPS), sucrose synthase (SUS), fructokinase (FRK), and hexokinase (HXK), play pivotal roles in these processes. However, a systematic and in-depth analysis of their regulatory mechanisms is currently lacking, which hinders a comprehensive understanding of the regulatory network governing fruit sugar metabolism. This review employs bibliometric analysis to systematically examine research trends in fruit sugar metabolism. Furthermore, it synthesizes recent advances in the coordinated regulatory mechanisms from the perspectives of transcriptional regulation, epigenetic modifications, and signal transduction, aiming to provide a clearer framework for future research. At the transcriptional level, transcription factor families such as MYB, WRKY, NAC, and MADS-box achieve precise regulation of sugar metabolism-related genes by specifically binding to the promoters of their target genes. Regarding epigenetic regulation, mechanisms including histone modifications, non-coding RNAs, and DNA methylation influence the expression of sugar-metabolizing enzymes at the post-transcriptional level by modulating chromatin accessibility or mRNA stability. Signaling pathways integrate hormonal signals (e.g., ABA, ethylene), environmental signals (e.g., temperature, light), and sugar-derived signals into the regulatory network, forming complex feedback mechanisms. These regulatory mechanisms not only directly affect sugar accumulation in fruits but also participate in fruit quality formation by modulating processes such as cell turgor pressure and carbon allocation. By integrating recent findings on transcriptional regulation, epigenetics, and signaling pathways, this review provides a theoretical foundation for fruit quality improvement and targeted breeding. Full article

Veraison represents a pivotal transition point in grape berry ripening, driven by a cascade of temporally coordinated physiological and molecular events. Studies have shown that the onset of veraison is initially triggered by a decline in cell turgor, regulated by osmotic potential and water status, which subsequently leads to fruit softening. This softening process is accompanied by extensive cell wall remodeling, establishing a structural basis for enhanced sugar influx. A rapid accumulation of sugars follows, acting not only as metabolic substrates but also as signaling molecules that synergize with abscisic acid (ABA) to activate transcriptional programs, including the induction of anthocyanin biosynthesis that drives skin color change. ABA accumulates at the early stages of veraison and functions as a key hormonal regulator initiating the ripening process. In contrast, auxin (IAA) and gibberellin (GA) levels decline prior to veraison, thereby releasing their inhibitory effects on ripening. Environmental factors such as water availability, light, and temperature significantly influence the timing and intensity of veraison by modulating hormonal signaling pathways. The initiation of grape berry ripening exemplifies a multilayered regulatory network that progresses through turgor signaling, hormonal regulation, metabolic reprogramming, and transcriptional activation, thereby providing a mechanistic framework for understanding non-climacteric fruit ripening. offering a mechanistic framework for understanding non-climacteric fruit ripening. This review provides an integrated perspective on the initiation mechanism of veraison, offering theoretical insights and practical implications for improving grape quality and vineyard management. Full article

Artificial muscles translate the biological principles of motion into soft, adaptive, and multifunctional actuation. This review accordingly highlights research into natural actuation strategies, such as skeletal muscles, muscular hydrostats, spider silk, and plant turgor systems, to reveal the principles underlying energy conversion and deformation control. Building on these insights, polymer-based artificial muscles based on these principles, including pneumatic muscles, dielectric elastomers, and ionic electroactive systems, are described and their capabilities for efficient contraction, bending, and twisting with tunable stiffness and responsiveness are summarized. Furthermore, the abilities of carbon nanotube composites and twisted yarns to amplify nanoscale dimensional changes through hierarchical helical architectures and achieve power and work densities comparable to those of natural muscle are discussed. Finally, the integration of these actuators into soft robotic systems is explored through biomimetic locomotion and manipulation systems ranging from jellyfish-inspired swimmers to octopus-like grippers, gecko-adhesive manipulators, and beetle-inspired flapping wings. Despite rapid progress in the development of artificial muscles, challenges remain in achieving long-term durability, energy efficiency, integrated sensing, and closed-loop control. Therefore, future research should focus on developing intelligent muscular systems that combine actuation, perception, and self-healing to advance progress toward realizing autonomous, lifelike machines that embody the organizational principles of living systems. Full article