Search Results (721)

The improvement of sucrose yield in sugarcane is impeded by the crop’s complex polyploid genome and slow progress in breeding. To clarify how arginine (Arg) regulates sugar metabolism and identify key genes associated with sucrose transport and accumulation in sugarcane, a screening experiment was performed by spraying L-arginine hydrochloride on the leaves and leaf sheaths of three sugarcane varieties (YZ05-51, YZ08-1609, and YT93-159), which differ in growth vigor, leaf morphology and other phenotypic traits. YZ05-51 exhibited the most prominent sugar-increasing effect, and subsequent optimization experiments on its leaf sheaths revealed that 20 g/mu L-arginine hydrochloride at pH 7.0 was optimal, significantly enhancing stem sucrose content. Transcriptomic analysis revealed the upregulation of genes related to sucrose synthesis and transport, with candidate genes enriched in pathways such as starch-sucrose metabolism, glycolysis/gluconeogenesis, and ATP-binding cassette (ABC) transporters. Metabolomic analysis detected 32 sugar metabolites across three categories, of which 24 were differentially abundant (e.g., glucose, galactose, fructose, and mannose). Integrated multi-omics analysis identified key regulatory genes, including SBEs and TPS1 (sucrose synthesis and carbon flux regulation), RBSK, α-amylases, GH28 (starch breakdown, glycolysis, and sugar mobilization), ABC transporters, GTs, and TIM10/TIM12 (sucrose transporter). Collectively, these analyses demonstrate enhanced activity of genes and metabolites involved in sucrose synthesis/transport in leaf sheaths, accompanied by reduced synthesis of other monosaccharides and oligosaccharides. Vigorously metabolizing leaf sheaths is more conducive to sucrose transport. This study provides valuable insights into the molecular mechanisms underlying Arg-mediated sucrose accumulation specifically in the sugarcane YZ05-51 sugarcane, highlighting its critical regulatory roles. Full article

Alpine shrub meadows on the Qinghai–Tibet Plateau are key warm-season pastures that support pastoral production and ecosystem stability in fragile high-elevation regions. Due to low temperatures, short growing seasons, and slow vegetation recovery, these pastures are highly sensitive to inappropriate grazing management. However, the effects of different grazing–rest time configurations on plant community composition and leaf functional traits in alpine shrub meadows remain insufficiently understood. In this study, we evaluated five grazing treatments in an alpine shrub meadow in Sunan County, central–eastern Qilian Mountains: 10 days grazing–20 days rest (T1), 15 days grazing–15 days rest (T2), 20 days grazing–10 days rest (T3), continuous grazing (CG), and grazing exclusion (CK). In the third year of treatment implementation, we measured the community diversity, species importance values, and leaf functional traits of four dominant species: Elymus nutans, Carex tibetikobresia, Oxytropis kansuensis, and Bistorta vivipara. T1 and T2 significantly increased species richness, Shannon–Wiener diversity, and Simpson diversity compared with CG and CK. NMDS and PERMANOVA further showed significant differences in overall community composition among grazing treatments. Grazing generally reduced the leaf length, leaf width, and leaf area, whereas T2 showed relatively stronger leaf recovery among grazing treatments. Specific leaf area, specific leaf weight, and leaf length–width ratio showed higher variability and calculated plasticity than leaf thickness and leaf dry matter content, suggesting that resource-acquisition and morphological traits were more responsive to grazing than conservative structural traits. The coefficient of variation of leaf traits was positively associated with the plasticity index, although this association should be interpreted cautiously because both indices were calculated from the same underlying trait dataset. Overall, under the conditions of this three-year, single-site experiment and a target moderate grazing intensity, the 15-day grazing–15-day rest regime performed best among the tested treatments. This regime may provide a practical reference for rotational grazing management in similar warm-season alpine shrub meadows, but its broader applicability requires further validation across different grassland types, grazing intensities, climatic conditions, and longer monitoring periods. Full article

Anthropogenic disturbances and climate warming threaten the rare paleoendemic species Tetracentron sinense. To identify the divers of its latitudinal adaptation, we integrated functional trait differentiation, environmental filtering, and phylogenetic conservatism. We measured 35 functional traits (leaf morphology, nutrient stoichiometry, stomatal traits, whole-plant architecture) across four natural populations spanning the species’ latitudinal range: BMXS (Baima Snow Mountain), DFD (Dafengding), FP (Foping), LGS (Leigong Mountain). Using correlation analysis, principal component analysis, and phylogenetic community metrics, we found that T. sinense dominated all communities. Populations exhibited divergent strategies: DFD expanded leaf area for light capture under high rainfall and shaded conditions; FP increased height and crown width to compete for light; LGS enhanced nutrient-use efficiency under phosphorus limitation; BMXS promoted phosphorus uptake under nitrogen limitation (N/P < 14). Trait variation correlated significantly with elevation, solar radiation, and temperature. PCA explained 90.44% of total variance, and standardized effect size (SES) values for phylogenetic signals range from −2.031 to 1.973; Phylogenetic signals were stronger in co-occurring taxa than in T. sinense. T. sinense populations in BMXS and FP are structured by competitive exclusion, while those in LGS and DFD by habitat filtering. We conclude that T. sinense achieves latitudinal adaptation by overcoming phylogenetic niche conservatism through phenotypic plasticity. While leaf economic traits remain evolutionarily conserved and niches in glacial refugium are relatively stable, populations adjust trait syndromes via metabolic shifts and structural trade-offs in response to heterogeneous environmental filters. Identifying these adaptive strategies can guide seed sourcing for restoration efforts under climate change. Full article

Glycine soja, the ancestor of cultivated soybean [Glycine max (L.) Merr.], is an important genetic resource for soybean improvement and a National Grade II Key Protected Wild Annual Plant in China. Understanding its intra- and interspecific interactions in natural communities is critical for effective conservation, yet these dynamics remain poorly characterized in field settings. This study aims to characterize these interactions within herbaceous communities, providing insights to optimize the management of G. soja populations and conservation reserves. We surveyed twenty natural G. soja communities and revealed the following: (1) G. soja exhibited stronger intraspecific than interspecific competition. Spatial patterning among morphotypes and their proportional displacement provided direct evidence of intraspecific interactions within G. soja populations. (2) The annual associated plant group exhibited coexistence mechanisms similar to G. soja, characterized by stronger intragroup competition relative to the perennial group, which conversely displayed stronger intergroup competition. (3) A significant negative correlation existed between perennials and annuals. Perennials posed a greater threat to G. soja than annuals via distinct threat mechanisms: while annuals suppressed G. soja primarily through proportional dominance in species number, perennials reduced G. soja density by leveraging G. soja’s tendency toward stronger intraspecific competition. (4) G. soja exhibited intraspecific niche differentiation among morphotypes defined by functional traits (leaf shape, leaf size, and plant height), where morphological similarity correlated with niche overlap. Extreme morphotypes followed a bimodal pattern, with intermediate forms acting as ecological buffers, thereby enhancing adaptation to heterogeneous environments. This study yields important implications for effective in situ conservation, requiring the mediation of the trade-off between intra- and interspecific competition. Optimal strategies should either maintain moderately open communities accessible to humans and grazing animals, thereby allowing residual associated plants to mitigate excessive intraspecific competition in G. soja while reducing intense interspecific competition, or employ artificial interventions in closed nature reserves to prevent excessive intra- and interspecific competitive exclusion of G. soja. Full article

To explore efficient and sustainable biocontrol resources against anthracnose in Begonia benariensis, endophytic fungi were isolated from healthy host tissues and screened for antagonistic activity against Colletotrichum aotearoa SWBG5. Among 31 isolates, four showed strong inhibition, and the most potent strain, QYN6, exhibited an in vitro mycelial inhibition rate of 63.67%. Based on morphology and multi-gene phylogeny (ITS, TUB2, TEF-1α), QYN6 was identified as Nigrospora sphaerica. Mechanistic assays revealed that QYN6 secretes multiple cell wall-degrading enzymes (chitinase, β-1,3-glucanase, cellulase, protease) and displays hyperparasitism against the pathogen hyphae (entwining, deformation, swelling), acting synergistically to inhibit fungal growth. In greenhouse pot trials, QYN6 achieved a biocontrol efficacy of 48.91% against Begonia anthracnose. Additionally, QYN6 significantly activated host defense responses, increasing the activities of antioxidant enzymes (SOD, POD, PPO, CAT) and the contents of soluble protein and soluble sugar. Furthermore, QYN6 exhibited multiple plant growth-promoting traits, including IAA production, siderophore synthesis, and potassium solubilization. Inoculation with QYN6 markedly improved plant height, leaf number, root length, and biomass of B. benariensis. Overall, N. sphaerica QYN6 possesses dual biocontrol and growth-promoting potential, providing a promising microbial resource and theoretical basis for green management of Begonia anthracnose. Full article

Drought stress is a major constraint on alfalfa (Medicago sativa L.) production. Screening for drought tolerance at the seedling stage can accelerate the identification of resilient germplasm. In this study, six alfalfa cultivars were selected and subjected to drought stress at the seedling stage. Morphological traits (stem diameter, plant height, biomass, and root–shoot ratio) and oxidative/antioxidant indicators (malondialdehyde (MDA), superoxide (O₂•⁻), superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), glutathione reductase (GR), and ascorbate peroxidase (APX) activity) were quantified in leaves and roots. Drought stress significantly reduced plant height (by up to 42.4% in ZL2) and biomass (by up to 30% in some cultivars), but increased the root–shoot ratio (by 50–166%). MDA and O₂•⁻ levels increased by 10–174% in leaves and 8–65% in roots across cultivars. Antioxidant enzyme activities rose markedly: SOD by 23–125% in leaves and 2–100% in roots; POD by 47–240% (leaves) and 38–166% (roots); CAT by 9–129% (leaves) and 30–227% (roots); GR by 35–107% (leaves) and 23–172% (roots); APX by 8–175% (leaves) and 3–89% (roots), indicating a coordinated leaf–root antioxidant defense. Transcriptome analysis of the tolerant cultivar ZM3 revealed 853 differentially expressed genes, which were enriched in pathways such as the non-homologous end-joining DNA repair pathway. Multivariate assessment of seedling-stage performance identified ZM3 and ZL2 as the most drought-tolerant cultivars. Collectively, these findings provide germplasm leads and empirical evidence for coordinated leaf–root antioxidant strategies in alfalfa, informing the selection and improvement of drought-tolerant cultivars. Full article

Nanotechnology has attracted increasing attention in agricultural and environmental research, but the biological effects and potential risks of nanoparticles based on non-essential elements remain insufficiently understood. This study investigated the physiological and biochemical responses of rice (Oryza sativa L.) seedlings to yttrium oxide nanoparticles (Y₂O₃ NPs) and zirconium oxide nanoparticles (ZrO₂ NPs) at 5, 25, and 100 mg/L under hydroponic conditions. The results showed that neither Y₂O₃ nor ZrO₂ NPs significantly affected visible growth traits or SPAD-based leaf chlorophyll status, suggesting that seedling morphology and leaf greenness remained relatively stable during exposure. However, both nanoparticles induced distinct biochemical responses. Y₂O₃ NPs caused root-level stress-like responses, including increased malondialdehyde (MDA) accumulation and suppressed peroxidase (POD) and catalase (CAT) activities under specific exposure conditions. In contrast, ZrO₂ NPs were more closely associated with the activation of antioxidant defenses, particularly through enhanced POD activity and increased root CAT activity. Inductively coupled plasma mass spectrometry (ICP-MS) analysis further showed that Y and Zr were mainly retained in roots, with root Y reaching 5014.12–11,255.05 mg kg⁻¹ dry weight (DW) under Y₂O₃ NP exposure and root Zr reaching 189.68 mg kg⁻¹ DW under high-concentration ZrO₂ NP exposure. Bio-transmission electron microscopy (bio-TEM) supported the root-dominant localization of nanoparticle-associated electron-dense aggregates. These findings indicate that Y₂O₃ and ZrO₂ NPs exert material-specific effects on rice seedlings, with root accumulation and antioxidant regulation serving as more sensitive indicators than visible growth traits. However, further research is needed to clarify the long-term environmental fate of Y₂O₃ and ZrO₂ NPs and to assess their potential ecological and food safety risks in agricultural systems. Full article

To clarify the effects of pond excavation and field elevation combined with biochar application on soil improvement and maize growth in cold-soaked fields in northern China, a two-year field experiment was conducted using maize as the test crop under five biochar application rates: 0, 7.5, 15, 22.5, and 30 t/ha. The effects of biochar application on soil water characteristics, maize root development, plant growth, and yield formation were investigated. The results showed that, under the pond excavation and field elevation treatment, the application of 22.5 t/ha biochar (B3) achieved the best overall improvement effect and significantly improved soil moisture conditions. At the heading stage, the soil water content in the 0–90 cm soil layer under the B3 treatment increased by 6.18% and 27.72% in the two experimental years, respectively, compared with the 0 t/ha biochar treatment (B0). In 2025, compared with the B0 treatment, root length density, root surface area density, and root volume density under the B3 treatment increased by 38.56%, 109.31%, and 65.35%, respectively, while the average diameter of maize fine roots decreased by 8.50%. Meanwhile, the leaf area index, plant height, stem diameter, kernels per ear, 100-kernel weight, and maize yield were all significantly increased, with grain yield reaching 13,991.10 kg/ha in 2025. Correlation analysis showed that the biochar application rate was significantly positively correlated with maize plant height, stem diameter, leaf area index, root morphological traits, and grain yield, indicating that biochar application promoted maize growth and yield by optimizing canopy structure and root architecture. These results demonstrate that pond excavation and field elevation combined with an appropriate biochar application rate can effectively improve cold-soaked fields in northern China and achieve stable and high maize yields, thereby providing technical support for the management of medium- and low-yield farmlands. Full article

Apple (Malus domestica Borkh.) rootstocks play a key role in modern intensive orchard systems, where their accurate identification is essential for breeding, nursery production, and certification of planting material. This is particularly important in Kazakhstan, a recognized center of origin of cultivated apple, where local germplasm remains insufficiently characterized at the molecular level. In this study, we integrated simple sequence repeat (SSR) genotyping and morphological trait analysis to develop a reliable approach for the identification of clonal apple rootstocks cultivated in Kazakhstan. Five widely used rootstocks (Zhetysu 5, ARM-18, B-7-35, M9, and B9) were analyzed using 17 polymorphic SSR markers and 30 vegetative traits. SSR analysis revealed moderate genetic polymorphism (PIC = 0.28–0.54; He = 0.35–0.58) and enabled clear discrimination among all studied genotypes. Cluster analysis based on genetic distances grouped rootstocks according to their genetic similarity, reflecting their origin and differentiation. Morphological evaluation demonstrated significant phenotypic variability and identified correlations among key vegetative traits related to plant vigor and leaf development. The integration of molecular and morphological data allowed the development of comprehensive genotype profiles (“molecular–morphological passports”) for each rootstock, ensuring their reliable identification. The proposed approach provides a practical framework for the certification of planting material and the management of apple genetic resources in Kazakhstan. It can be applied to improve nursery systems, support breeding programs, and ensure the production of true-to-type planting material in modern horticulture. Full article

In transitional tropical ecosystems such as the Amazonia–Cerrado ecotone, dominant tree species experience strong environmental heterogeneity, requiring coordinated functional strategies to cope with drought, nutrient limitation, and disturbance. However, how these species integrate leaf morphoanatomical traits and wood density to persist in such environments remains poorly understood. We assessed the coordination among leaf anatomical and morphological traits and their relationship with wood density in five dominant tree species across three savanna park sites in the Amazonia–Cerrado transition. Morphological traits included leaf thickness, specific leaf area, leaf dry matter content, and wood density, alongside 17 anatomical leaf traits. We analyzed inter- and intraspecific variation and covariation patterns to identify trait-based ecological strategies along the acquisitive–conservative spectrum. We found strong coordination among traits related to protection (e.g., cuticle thickness and trichomes) and resource use, as well as clear alignment between leaf and wood traits. Species identity explained most trait variation, although leaf thickness showed notable intraspecific plasticity. Species with conservative traits exhibited thicker leaves and higher wood density, whereas species with acquisitive strategy showed higher specific leaf area and lower leaf dry matter content. Overall, trait coordination reflects integrated ecological strategies shaped by environmental heterogeneity, highlighting the role of multi-trait syndromes in driving functional adaptation in ecotonal systems. Full article

Understanding the internal translocation of sodium (Na) and potassium (K) within the soil–plant continuum is crucial for elucidating their mechanistic roles in plant growth adaptation. We investigated these processes in the Suaeda salsa across a natural salinity gradient in the Yellow River Delta coastal wetlands. Using field surveys, we quantified Na and K enrichment and translocation coefficients among soil, roots, stems, and leaves. The correlation analysis and Random Forest modeling were then employed to identify the key drivers linking these ion dynamics to plant morphological traits (height, density, biomass). Results revealed a pronounced Na compartmentalization, with leaves acting as the primary sink (enrichment coefficient = 5.62), exhibiting values 4.68- and 3.81-fold higher than roots and stems, respectively. In contrast, K enrichment levels remained relatively stable across plant organs (roots: 0.50; stems: 0.57; and leaves: 0.62). Internal Na⁺ loading in stems and leaves positively correlated with leaf Na enrichment. Conversely, high soil Na suppressed both leaf Na enrichment and stem-to-leaf K translocation, while elevated soil K reduced K enrichment in all organs and soil-to-root Na translocation. Critically, plant height was negatively correlated with Na-K enrichment coefficients in all organs. Population density and biomass were specifically linked to stem-related Na dynamics (stem-leaf Na translocation and stem Na enrichment), with K translocation showing no significant relationship. The Random Forest model identified the stem K enrichment coefficient, leaf K content and its enrichment coefficient, and stem Na content as the most influential coefficients governing plant growth (relative importance: 6.37~12.82%). We conclude that the growth adaptation of S. salsa in this coastal ecosystem is driven by a synergistic yet organ-specific regulation of Na and K translocation and homeostasis. These findings provide a mechanistic physiological basis for informing ecological restoration strategies of S. salsa wetlands and support the sustainable management of estuarine ecosystems. Full article

Amazonian white-sand forests (campinarana) are highly specialized ecosystems characterized by nutrient-poor sandy soils and pronounced seasonal variation in water availability. Plant species inhabiting these environments are exposed to alternating periods of water deficit and soil saturation, which may strongly constrain recruitment and early establishment. Aldina heterophylla is an endemic tree species specialist in these habitats. This study evaluated seed germination, biomass allocation, anatomical traits, and early seedling responses of A. heterophylla under contrasting water regimes: control, partial flooding, and drought. Seedling performance was assessed after 50 and 100 days of treatment. After 50 days, flooded seedlings showed significantly greater root biomass than control plants, indicating short-term plastic adjustment to saturated soils. However, prolonged flooding induced chlorosis, necrosis, leaf abscission, and partial mortality. In contrast, drought-stressed seedlings developed leaf senescence but maintained 100% survival throughout the experiment. Morphological and physiological traits varied significantly over time among treatments, particularly leaf number, height, and chlorophyll dynamics. The results indicate that A. heterophylla seedlings are more tolerant to water deficit than to prolonged flooding, although they display adaptive responses to temporary soil saturation. These findings improve understanding of regeneration processes in Amazonian white-sand ecosystems and provide relevant information for conservation planning under increasing climatic extremes. Full article

Atraphaxis virgata and Atraphaxis pyrifolia are xerophytic species of the Polygonaceae family that remain insufficiently characterized from pharmacognostic, phytochemical, and toxicological perspectives. This study provides an integrated evaluation of both species through anatomical authentication, sequential extraction of CO₂-extracted residual biomass, GC–MS and LC–MS metabolite profiling, and acute oral toxicity assessment. Anatomical analysis revealed shared xeromorphic traits, including cuticular protection, dorsiventral mesophyll organization, structured vascular bundles, and calcium oxalate druses. It also identified species-specific differences in leaf thickness, mesophyll arrangement, vascular architecture, and druse morphology. GC–MS analysis showed distinct chemical profiles: A. virgata displayed a concentrated profile dominated by acetophenone- and benzofuran-related constituents, whereas A. pyrifolia showed a broader spectrum of carbohydrate-derived, phenolic-related, and oxygenated constituents. LC–MS analysis supported the tentative annotation of diverse polyphenolic classes, including flavonoids, phenolic acids, coumarins, and phenylpropanoid derivatives. Acute oral toxicity testing showed no mortality at doses up to 2000 mg/kg, supporting a low acute oral toxicity classification under the tested conditions. However, histological examination revealed mild to moderate dose-dependent alterations in liver and kidney tissues at higher doses. The novelty of this work lies in linking diagnostic anatomical traits, species-specific metabolite patterns, residual biomass valorization, and preliminary safety evidence within a single comparative framework. These findings provide a basis for pharmacognostic authentication, phytochemical standardization, and future bioactivity-guided evaluation of Atraphaxis species. Full article

Forest tree provenances have evolved diverse and complex mechanisms to acclimate to changes in environmental conditions. Pedunculate oak (Quercus robur L.), along with other European tree species, is increasingly exposed to the adverse effects of climate change, particularly prolonged drought periods and severe drought stress. Understanding the species’ capacity to acclimate to expected environmental changes requires knowledge of key functional traits linked to drought tolerance, such as leaf structure and gas exchange. To explore the acclimation mechanisms of pedunculate oak provenances to repeated drought events, a study was conducted under controlled conditions with plants from nine provenances spanning a north–south gradient across eastern Europe, from Estonia to Italy. The study consisted of two parts: first, leaf structural traits were analyzed after three years of experimentally induced drought by comparing drought and control treatments; second, both treatments were subjected to subsequent drought to analyze differences in gas exchange trait responses. Results demonstrated ecotypic differentiation among provenances in morphological, but not in gas exchange traits, suggesting that provenance adaptedness to drier habitats is more closely associated with structural than physiological traits. Provenances originating from drier habitats showed lower specific leaf area but also different acclimation to repeated drought events, including a stronger reduction in stomatal density and a smaller increase in leaf dry matter content, compared to provenances from more humid habitats. Gas exchange acclimation occurred through a shift in the strategy of photosynthesis down-regulation. These findings emphasize the importance of investigating multiple functional traits rather than focusing solely on individual key traits. Full article

Alpinia hainanensis Hayata (family Zingiberaceae) is a medicinal plant with high potential for understory cultivation, but the variations in growth, morphological status, physiological conditions, nutrient absorption and phytochemical contents between different understory provenances originating from southern China remain poorly understood. In this study, different growth, physiological and phytochemical indices of three provenances [Hainan (HN) and Bobai (BB)/Baise (BS) from Guangxi] were determined, in order to better evaluate their introduction potentials. The results showed that two Guangxi provenances (BB and BS) showed superior aboveground growth and biomass accumulation compared to the HN provenance, yet most the leaf functional traits and medicinal qualities of some organs were similar. Sprout and leaf growth were consistent, and a negative correlation was observed between leaf nitrogen and flavonoid content. Based on principal component analysis (PCA), BB performed better than two other provenances in growth and phytochemical aspects. Due to the limited number of collections of provenances and absence of microclimate data, these findings should be considered preliminary. This study provides a basis for provenances selection and understory cultivation in A. hainanensis in (sub)tropical regions. Full article