Search Results (399)

Functional steel surfaces engineered through tailored micro-nano structures are increasingly vital for various applications such as high-performance aerospace components, energy conversion systems and defense equipment. Femtosecond laser filament processing is a recently proposed remote fabrication technique, showing the capability of fabricating micro-nano structures on irregular and large-area surfaces without the need of tight focusing. Nevertheless, the mechanisms underlying the formation of filament-induced structures remain not fully understood. Here we systematically investigate the formation mechanisms of filament-induced micro-nano structures on stainless steel surfaces by processing stainless steel in three manners: point, line, and area. We clarify the decisive role of the unique core–reservoir energy distribution of the filament in the formation of filament-induced micro-nano structures, and reveal that ablation, molten metal flow, and metal vapor condensation jointly drive the structure evolution through a dynamic interplay of competition and coupling, giving rise to the sequential morphological transitions of surface structures, from laser-induced periodic surface structures to ripple-like, crater-like, honeycomb-like, and ultimately taro-leaf-like structures. Our work not only clarifies the mechanisms of femtosecond laser filament processed morphological structures on steels but also provides insights onto intelligent manufacturing and design of advanced functional steel materials. Full article

Rapid and accurate identification of crop leaf diseases is essential for informed agricultural decision-making. However, achieving reliable classification remains challenging under conditions such as extreme lighting, complex color variations, and intricate structural backgrounds, particularly when early-stage symptoms are subtle and easily masked by surrounding tissues. To address these challenges, this study proposes a novel network architecture, SREM-Net, which incorporates stylistic and multiscale feature extraction strategies. Specifically, the model introduces the style recalibration MBconv (SRMB) to mitigate feature dilution caused by the coexistence of lesions and complex backgrounds. In addition, the EMF dynamically adjusts the receptive field, enabling the model to capture lesion distributions across the entire leaf while simultaneously emphasizing morphological details, edges, and fine-scale features. To improve interpretability, Gradient-weighted Class Activation Mapping (Grad-CAM) was employed to generate visual explanations of the detected diseases. On our self-constructed, weather-augmented MCCD dataset, the experimental results demonstrate that SREM-Net outperforms state-of-the-art networks such as LWMobileViT, MobileNetV3-CA, and LWDN, achieving F1-score improvements of 2.13%, 1.21%, and 1.18%, respectively. Full article

Extended droughts are predicted for southwestern North America, including the arid Mojave Desert, which has plant communities dominated by desert scrub vegetation. We conducted a multi-year study in which supplemental water was provided to four native shrub species: the evergreen Larrea tridentata and deciduous Ambrosia dumosa, Ambrosia salsola, and Encelia farinosa. Water treatments included −25% of precipitation (by temporarily deploying large tarps over wooden support structures), actual precipitation, and 100% and 200% of actual precipitation. Water applied occurred within 24 h of actual precipitation events. At the end of a two-year period, we allowed the plots to remain intact, receiving no supplemental water for 3.8 years, which was anomalously dry. During the initial two-year experiment, we examined growth and other physiological responses to the treatments. We also measured soil volumetric water content with depth and calculated a plant water stress index. After the 3.8-year dry period we measured stem elongation, canopy volume, leaf xylem water potential and harvested roots and shoots for biomass estimates. Supplemental water led to higher soil water content and water use, leading to increased aspects of growth which were species dependent, whereas the −25% treatment resulted in greater stress and reduced growth, but only in some species. After the 3.8-year dry period, survival in all treatments was between 97 and 100%. However, a distinct legacy effect was observed, as plants growing under the wetter treatments during the 2-year supplemental water period had more negative leaf xylem water potentials after the 3.8-year dry period than plants that were grown under the drier treatments. In addition, canopy volumes were shown to decrease if plants were grown under the wetter treatment imposed during the supplemental water period but increased if grown under the drier treatments. Our results would suggest that the impact of climate change on Mojave Desert shrubs will be linked to how they respond to wet/dry cycles, which will be linked to drought severity and the time between wet periods. The four shrub species studied have unique morphological and physiological characteristics that allow them to grow and not just survive under arid conditions, but if extended drought events occur on a more frequent basis, these shrub species may not be able to adapt and thus avoid higher mortality rates. Full article

The floral morphology of Rosa chinensis significantly influences its ornamental value. However, the molecular mechanisms underlying specific floral types remain poorly understood. Viridiflora, a stable genetic variant of R. chinensis, exhibits homeotic transformation of floral organs into sepal-like structures, providing a valuable model for studying floral organ identity and development. In this study, Viridiflora was compared with Old Blush to elucidate floral development through morphological observation, transcriptomic profiling, and functional genetics. Four distinct developmental stages were defined, encompassing the formation of sepal, petal, stamen, and pistil primordia. Transcriptome analysis identified candidate genes associated with the Viridiflora phenotype, among which RcAGAMOUS2 (RcAG2) and RcFRUITFULL (RcFUL) were selected for in-depth functional characterization. The proteins encoded by these two genes are hydrophilic, lack signal peptides and transmembrane domains, and contain multiple phosphorylation sites. They feature typical MADS-box family domains and show close phylogenetic affinity to Rosa rugosa. Subcellular localization showed their nuclear presence. Heterologous overexpression of RcAG2 and RcFUL in Arabidopsis resulted in notable phenotypic alterations: RcAG2 caused petal reduction and stamen exposure, while RcFUL led to greenish, leaf-like petals with pigmentation gradients, increased sepal number, and failed seed set. Conclusion: These results suggest that RcAG2 and RcFUL play key roles in floral organ development through genetic regulation, providing a theoretical foundation for further research on floral development in R. chinensis. Full article

Prolonged low-light stress during growth significantly reduces rice yield in southwest China. In order to systematically study the dynamic response of rice to long-term shading, field experiments were conducted in Chongqing, China, from 2021 to 2022, investigating the effects of 50% and 75% shading from the seedling to heading stage on morphological characteristics, physiological traits, and yield formation in 12 rice cultivars. The results showed that shading reduced tiller number, leaf mass per area, total dry mass, leaf area index, panicle number, seed-setting rate, and yield. Meanwhile, rice acclimated to low light by increasing plant height, leaf chlorophyll content, and leaf-total mass ratio. In particular, leaf width in low-light treatments was narrower under short-term shading but became wider under long-term shading compared to natural light. Moreover, under 50% shading condition, rice optimized panicle structure by increasing grain number per panicle and primary and secondary branch numbers to compensate for adverse effects. Cultivars, including Le you 918 and Shen 9 you 28, exhibited high yield and strong shade tolerance. Overall, rice acclimates to low light through the synergistic interactions of various traits, with leaf phenotypic adjustments and panicle structure optimization being crucial for improving yield under low light. Full article

The aim of the study was to determine the effect of cultivar and nitrogen fertilization on the morphological and physiological traits and yield of soybean (Glycine max (L.) Merrill) grown in central-eastern Poland. In a strict, two-factor field experiment, four soybean cultivars were used: ‘Abelina’, ‘Malaga’, ‘Coraline’, and ‘Petrina’, and three nitrogen rates: 0, 30, and 60 kg N ha⁻¹. The moderate rate (N30) was applied before sowing, while the higher rate (N60) was divided into two parts, with 50% applied before sowing and 50% top-dressed at BBCH 61. The studies were conducted during two growing seasons. It was shown that both the cultivar and nitrogen fertilization significantly affected plant height, leaf area index (LAI), leaf greenness index (SPAD), and chlorophyll fluorescence indices (Fv/Fm, PI). The interaction among cultivar, fertilization, and years was significant for SPAD and Fv/Fm index, indicating a strong influence of environmental factors on plant response. Nitrogen fertilization increased plant height and chlorophyll content but reduced fluorescence indices. Among the cultivars studied, the late-season cultivar ‘Malaga’ was characterized by the highest SPAD index (502), Fv/Fm (0.800), and PI values (4.3), and achieved the highest seed yield (5.06 t ha⁻¹) and thousand-seed weight (230 g). In contrast, the medium-season cultivar ‘Abelina’ showed the lowest SPAD (454), and significantly lower Fv/Fm and PI values (0.790 and 3.51, respectively), resulting in the lowest yield (4.25 t ha⁻¹) and TSW (169.7 g). The application of a moderate rate of nitrogen (N30) improved the physiological indicators of plants and elements of yield structure without reducing the potential photochemical efficiency of PSII, while a higher rate (N60) did not result in a significant increase in yield, despite a greater number of pods and seeds per plant, which may have been due to a reduction in thousand-seed weight. The results highlight the importance of cultivar selection and moderate N fertilization of soybean grown in temperate climates and indicate the need for further research on the physiological mechanisms that determine cultivar-specific nitrogen use efficiency and yield stability under environmental stress. Full article

The design of efficient catalysts is vital for the application of catalytic oxidation technology in the removal of gaseous pollutants. Herein, a series of MnO_x catalysts with the typical Mn₂O₃ crystal structure was synthesized via the high-temperature pyrolysis method by using Mn-based metal–organic frameworks (Mn-MOFs) with various morphologies as the precursors. The physicochemical properties of these Mn-MOF-derived MnO_x samples were investigated by various characterization techniques, including X-ray diffraction (XRD), thermogravimetry (TG), N₂ adsorption–desorption, scanning electron microscope (SEM), and H₂ temperature-programmed reduction (H₂-TPR), and their catalytic activity was evaluated for catalytic CO degradation. The results showed that the Mn-MOF with leaf-like morphology, derived MnO_x-Leaf, presented the optimal catalytic CO oxidation performance (T₉₈ = 214 °C), stability, and reusability. Characterization results showed that the different Mn-MOF-derived MnO_x catalysts possessed different physical–chemical properties. The superior catalytic activity of MnO_x-Leaf for CO degradation was ascribed to its large surface area and pore size, better low-temperature redox properties, and high H₂ consumption, which promoted the adsorption and activation of the CO and gaseous oxygen molecules, improving CO oxidation. Finally, the possible CO degradation pathway was evaluated by in situ diffuse reflectance Fourier transform infrared spectroscopy (DRIFTS), which showed that gaseous CO and O₂ were adsorbed on the surface of the catalyst and oxidized to form surface carbon-related species (bicarbonate and carbonate), and finally converted to CO₂. Full article

Global climate change has intensified land desertification in the arid and semi-arid regions of northwestern China, highlighting the urgent need to cultivate plant species with ideal architecture and well-developed root systems to combat ecosystem degradation. Amorpha fruticosa is widely used as a windbreak and sand-fixation shrub; however, its rapid growth and high transpiration during the early planting stage often result in excessive water loss, low survival rates, and limited vegetation restoration effectiveness. Plant growth retardants (PGRts) are known to suppress apical dominance and promote branching. In this study, one-year-old A. fruticosa seedlings were treated with different combinations of paclobutrazol (PP₃₃₃) and uniconazole (S₃₃₀₇) to investigate their effects on plant morphology and biomass allocation; it aims to determine the optimal formula for cultivating shrub structures with excellent windbreak and sand-fixation effects in land desertification areas. The results showed that both PP₃₃₃ and S₃₃₀₇ significantly inhibited plant height while promoting basal stem diameter, branching, and root development. Among all treatments, the S₃₃₀₇ 200 mg·L⁻¹ + PP₃₃₃ 200 mg·L⁻¹ combination (SD3) was the most effective, resulting in the greatest increases in basal diameter, branch number, total root length, and root-to-shoot ratio, while significantly reducing height increment, leaf length and leaf area (p < 0.05). Under the S₃₃₀₇ 200 mg·L⁻¹ + PP₃₃₃ 300 mg·L⁻¹ treatment (SD4), leaf width and specific leaf area were reduced by 17.92% and 38.89%, respectively, compared with the control. Correlation analysis revealed significant positive or negative relationships among most growth traits, with leaf length negatively correlated with other morphological indicators. Fresh and dry weights of both aboveground and root tissues were significantly positively correlated with basal diameter (R = 0.38) and branch basal diameter (R = 0.33). Principal component analysis demonstrated that the SD3 treatment achieved the highest comprehensive score (2.91), indicating its superiority in promoting a compact yet robust plant architecture. Overall, the SD3 treatment improved drought resistance and sand-fixation capacity of A. fruticosa by “dwarfing and strengthening plants while optimizing root–shoot allocation.” These findings provide theoretical support for large-scale cultivation and vegetation restoration in arid and semi-arid regions and offer a technical reference for growth regulation and windbreak and sand-fixation capacity in other xerophytic shrub species. Full article

The olive tree (Olea europaea L.), a cornerstone of Mediterranean agriculture, is widely recognized for its inherent drought tolerance. However, the increasing frequency and intensity of water deficit events driven by climate change are challenging its growth, productivity, and long-term sustainability. This review synthesizes current knowledge on the morphological and phenological adaptations of olive trees to water stress. In fact, under drought conditions, olive trees develop a suite of structural and anatomical adjustments that collectively enhance water-use efficiency and help maintain plant water status. These adjustments include reduced leaf area, thickened cuticles, mesophyll rearrangements, remodeling of xylem vessel architecture, and reinforced root systems. These morpho-anatomical responses influence phenology, through changes in the timing and duration of key phenological stages, leading to reduced flower induction, lower flowering intensity, decreased fruit set, and overall lower yields, while the most pronounced effects are observed in sensitive cultivars. Among all stages, flowering is the most vulnerable to water deficit, while pit hardening and fruit development show comparatively more tolerance. The combination of morphological, anatomical, and phenological responses could provide a mechanistic elucidation of drought tolerance variability within olive cultivars. Understanding this interplay is likely to offer valuable criteria in selecting and breeding resistant varieties, thus ensuring productive and sustainable olive cultivation under increasingly severe climatic conditions. Full article

Accurate identification of grape leaf varieties is an important prerequisite for effective viticulture management, contributing to breeding programs, cultivation strategies, and precision field operations. However, reliable recognition in complex field environments remains challenging. Subtle interclass morphological variations among leaves, background interference under natural conditions, and the need to balance recognition accuracy with computational efficiency for mobile applications represent key obstacles that limit practical deployment. This study proposes an improved lightweight convolutional neural network, termed ICS-MobileNetV3-Small (ICS-MS), specifically designed for grape leaf variety recognition. The model’s core innovations, detailed in Key Innovations of the Proposed ICS-MS Model section, include three key components: First, a coordinate attention mechanism is embedded to enhance the network’s ability to capture spatially distributed features while suppressing irrelevant background noise. Second, a multi-branch ICS-Inception structure is integrated to accomplish excellent multi-scale feature fusion, allowing the model to discern minute textural variations among types. Moreover, the feature representation is further optimized by adopting a joint loss function, which improves feature space distribution and enhances classification robustness. Experimental evaluations were conducted on a dataset comprising eleven grape leaf varieties. The proposed ICS-MS model achieves a recognition accuracy of 96.53% with only 1.17 M parameters. Experimental results demonstrate that, compared with the baseline MobileNetV3-Small model, the standalone integration of the Coordinate Attention (CA) mechanism improves accuracy by 0.17% while reducing the number of parameters by 10.4%. Furthermore, incorporating the ICS-Inception structure leads to an additional 4.78% accuracy improvement with only a marginal increase in parameter count. Finally, the introduction of a joint loss function provides an extra 0.23% gain in accuracy, resulting in an overall parameter reduction of approximately 23.5% compared with the baseline model. Three core contributions are highlighted as follows: (1) the construction of an integrated technical framework of “spatial feature enhancement—multi-scale fusion—feature distribution optimization” to systematically address the key issues of insufficient fine-grained feature extraction and the balance between lightweight design and accuracy; (2) the design of a lightweight CA-Block module that reduces parameters by 18.7% while enhancing spatial feature discrimination; (3) the achievement of superior performance with fewer parameters, providing a practical solution for mobile deployment in precision viticulture. Values for precision, recall, and F1-score were continuously near 96%, suggesting a good trade-off between efficiency and accuracy. These findings suggest that ICS-MS provides a practical and reliable approach for grape leaf identification and may serve as a useful tool to support intelligent management in precision viticulture. Full article

Thigmomorphogenesis denotes a suite of anatomical, physiological, biochemical, biophysical, and molecular responses of plants to mechanical stimulation. This phenomenon is evolutionarily conserved among diverse plant lineages; however, the magnitude and character of the response are strongly determined by both the frequency and intensity of the applied stimulus. In angiosperms, thigmomorphogenetic reactions typically occur gradually, reflecting a complex interplay of morphological alterations, biochemical adjustments, and genetic reprogramming. In dicotyledonous plants, thigmomorphogenesis is commonly expressed as a reduction in leaf blade surface area, shortening of petioles, decreased plant height, radial thickening of stems, and modifications in root system architecture. In monocotyledons, in turn, mechanical stress frequently results in stem rupture below the inflorescence, with concomitant shortening and increased flexibility of younger internodes. These specific traits can be explained by structural features of monocot secondary walls as well as by the absence of vascular cambium and lateral meristems. Mechanical stimulation has been shown to initiate a cascade of responses across multiple levels of plant organization. The earliest events involve activation of mechanoresponsive genes (e.g., TCH family), followed by enzymatic activation, biochemical shifts, and downstream physiological and molecular adjustments. Importantly, recent findings indicate that prolonged mechanical stress may significantly suppress auxin biosynthesis, while leaving auxin transport processes unaffected. Moreover, strong interdependencies have been identified between thigmostimulation, gibberellin biosynthesis, and flowering intensity, as well as between mechanical stress and signaling pathways of other phytohormones, including abscisic acid, jasmonic acid, and ethylene. At the molecular scale, studies have demonstrated a robust correlation between the expression of specific calmodulin isoforms and the GH3.1 gene, suggesting a mechanistic link between mechanosensing, hormone homeostasis, and regulatory feedback loops. The present study consolidates current knowledge and integrates novel findings, emphasizing both morphological and cellular dimensions of thigmomorphogenesis. In particular, it provides evidence that mechanical stress constitutes a critical modulator of hormonal balance, thereby shaping plant growth, development, and adaptive potential. Full article

Estimated climate change scenarios demand robust coffee cultivars tolerant to supra-optimal temperatures, water deficit, diseases, and other stresses. Wild Coffea species represent important genetic resources for resilience. The study of variations in morphological structures associated with transpiration control, such as stomata, represents an important approach for identifying genotypes with greater stress tolerance. This study evaluated stomatal density and morphology in 48 wild accessions, 24 of Coffea racemosa and 24 of C. zanguebariae, from provinces of Mozambique. Leaf samples provided microscopic images to assess stomatal traits: density (SD), polar diameter (PD), equatorial diameter (ED), stomatal functionality (SF), and leaf dry mass. Principal components were analyzed for all 48 accessions and separately by species. Mean distribution independence was tested with the Mann–Whitney test (p < 0.05). Results revealed inter- and intraspecific variation. The ability to distinguish accessions varies with the set of traits and species. A significant negative correlation between ED and SF was shared by both species, suggesting a conserved functional pattern. This study discusses the differences in stomatal traits between wild and commercial coffee species and aspects related to possible alterations of stomatal structures during their adaptation to climate change. Additionally, it points to accessions with potential use in genetic breeding programs to increase stomatal function and the possible adaptation of new cultivars. Full article

Bacterial leaf blight (BLB), a destructive disease of rice caused by Xanthomonas oryzae pv. oryzae (Xoo), continues to limit rice productivity worldwide. Although biologically synthesized zinc oxide nanoparticles (ZnO NPs) have been extensively investigated, knowledge regarding the antibacterial activity and biocompatibility of commercially available ZnO NPs is still limited. In this study, commercial ZnO NPs were systematically characterized and evaluated for their antibacterial mechanisms and biocompatibility in mammalian cells. FE-SEM and TEM analyses revealed irregular polyhedral, hexagonal, and short rod-like morphologies with an average particle size of ~33 nm, consistent with crystallite sizes estimated by XRD. The nanoparticles exhibited pronounced antibacterial activity against Xoo, with a minimum inhibitory concentration (MIC) of 16 µg/mL and a clear dose-dependent response. Mechanistic assays confirmed multifaceted bactericidal actions involving membrane disruption, ROS generation, Zn²⁺ release, and ultrastructural damage. Biocompatibility testing in human dermal fibroblasts showed enhanced proliferation at 8–32 µg/mL, no cytotoxicity up to 256 µg/mL, and reduced viability only at ≥512 µg/mL. These findings represent the first mechanistic evaluation of commercial ZnO NPs against Xoo, together with cytotoxicity assessment in mammalian cells, highlighting their structural distinctness and dual functionality that combine potent antibacterial activity with minimal mammalian cytotoxicity. Overall, the results underscore their potential as safe nanobiocontrol agents for sustainable rice disease management. Full article

Thinopyrum intermedium (c.n. intermediate wheatgrass), marketed under the trade name Kernza, is a promising species for perennial grain production based on seed size, ease of threshing, resistance to shattering, and grain quality. Although numerous generations of breeding for seed yield have been completed, the impact of selection on non-target traits is unknown. Here, we evaluated structural and functional changes brought about by selection for seed yield over a sequence of nine selection cycles (C0 to C9). In two experiments under semi-controlled environmental conditions, we compared gas exchange (A, E, gs, and A/Ci curves), leaf and root morphology, and the structure of seedlings from 10 generations. We found that the selection for yield throughout cycles indirectly changed the leaf structure (leaf size, leaf thickness, and leaf anatomy) and physiology (carbon acquisition and transpiration per unit area), with later cycles showing larger leaves with higher rates of CO₂ assimilation and transpiration. Changes in root structure followed similar trends: selection resulted in longer, more branched, and finer roots. These changes in non-target traits are linked to resource-use strategies and to ecosystem services provided by Kernza. Understanding how the domestication of perennial grains impacts non-target traits will aid in the design of integrated breeding programs for Kernza and other perennial grain crops. Full article

This study investigates the role of leaf shape in detecting disease in tomato plants, grounded in the observation that plant leaves often undergo structural changes in response to infection. Healthy and diseased tomato leaves are characterized by extracting shape signature features from images and analyzing their spectral characteristics. Leaf images were captured using a Sony ZV-E10 Mark II mirrorless camera equipped with a Sigma 16 mm f/1.4 DC DN lens. Each leaf was placed flat on a matte white surface under a controlled overhead photography setup. The camera was mounted at a fixed height on a tripod, and uniform illumination was achieved using two symmetrically positioned LED spotlight lamps, minimizing shadows and glare. The dataset comprises 200 samples: 100 healthy and 100 diseased tomato leaves, representing a range of morphological and pathological variations. Three primary shape metrics were extracted from the images to characterize the structural differences: (1) the Centroid Contour Distance measured the radial distances from the leaf centroid to its outer contour; (2) the Hausdorff Distance quantified the geometric dissimilarity between contours; and (3) the Dice Similarity Index assessed the degree of overlap. In addition, spectral characteristics were derived from the RGB channels: mean intensities of red, green, blue, and the Excess Green Index. Results show that both shape and spectral features are valuable for detecting plant diseases: PCA shows clustering patterns between the two classes of leaves, and correlation analysis highlights the relationship between several pairs of geometric and color features. In conclusion, shape is an essential aspect of plant health, as it reflects the structural changes that occur as a result of disease. Full article