Search Results (1,766)

Drought stress is a significant environmental factor affecting plant growth, fruit quality and distribution. Wild jujube is an important species of eco-economic forest tree. In this study, two wild jujube families, ‘NO. 1’ (tolerant) and ‘NO. 5’ (sensitive), which show significant differences in morphological and physiological indicators in drought treatment, are considered. Compared with the ‘NO. 5’, the ‘NO. 1’ exhibited lower water loss, leaf yellowing and abscission rates, as well as reduced malondialdehyde (MDA) content, while showing higher superoxide dismutase (SOD) activity and elevated levels of soluble sugars (SS), soluble proteins (SP), and proline (Pro). In contrast, the ‘NO. 5’ suffered more severe damage to leaf epidermal cells compared with the ‘NO. 1’, accompanied by a significant decline in net photosynthetic rate (A) and instantaneous water use efficiency (WUEi). Transcriptomic profiles between two wild jujube families with markedly different drought responses (withholding water for 15 days) are shown. The two wild jujube families included 3238 up-regulated and 2675 down-regulated differentially expressed genes (DEGs). Many DEGs enriched in the GO and KEGG pathways are related to antioxidant activity, transmembrane transport, carbohydrate biosynthesis and metabolism, plant hormones, and photosynthesis. The biosynthesis of amino acids, the MAPK signaling pathway, plant hormone signal transduction, and flavonoid and alkaloid biosynthesis were the transcriptome modifications most significantly altered by drought stress. Real-time quantitative polymerase chain reaction (RT-qPCR) was used to verify the precision of the RNA-seq data. ZjJIP23-1, ZjbZIP53, ZjSPS8, ZjCAO, ZjADH1 and ZjERF39 may play important roles in the drought tolerance of the wild jujube. This study provides a solid foundation for further studies on the complex mechanisms and breeding of drought-resistant plants in wild jujube. Full article

Drought stress severely restricts the growth of pear trees. As a widely used drought-tolerant rootstock, Pyrus betulifolia exhibits stable growth performance; however, the molecular mechanisms underlying its drought tolerance remain to be elucidated. In this study, we investigated the molecular responses of P. betulifolia leaves to osmotic stress induced by 20% PEG-4000 using time-series RNA-seq technology. A total of 3745 differentially expressed genes were identified, with transcriptional changes peaking at 6 h, indicating a critical phase of transcriptional reprogramming during drought response. Genes associated with osmotic adjustment (e.g., P5CS) and oxidative stress responses (e.g., SOD and POD) were significantly upregulated between 6 and 12 h. Weighted gene co-expression network analysis (WGCNA) identified three distinct temporal modules and screened out NF-Y, RVE1, COL9, COL6, C2C2 zinc finger proteins, and Pseudo ARR-B as putative key regulators, whose expression patterns were validated using qRT-PCR. Collectively, these results provide a comprehensive view of the temporal transcriptional dynamics of drought response in P. betulifolia and offer valuable candidate gene resources for further functional studies and drought tolerance breeding. Full article

Ash dieback is an often-fatal disease caused by the fungus Hymenoscyphus fraxineus (T. Kowalski) Baral, Queloz & Hosoya. It emerged in Europe during the 1990s and poses a substantial threat to ash populations. In Hungary, symptoms were first detected on common ash (Fraxinus excelsior L.) in 2008. The disease also severely impacts another native species, the narrow-leaved ash (Fraxinus angustifolia Vahl). An effective strategy for counteracting ash decline is to identify and utilize sources of tolerance. We are monitoring the health status of the selected trees that demonstrate low susceptibility (plus trees) and conducting molecular genetic studies to enable their genetic characterization and individual identification using 16 nuclear microsatellite (nSSR) markers. The PCoA (Principal Coordinates Analysis) separated the eight assessed groups into two distinct clusters based on the taxonomic traits. Based on the Structure analysis results, K = 2 was the most probable cluster number. Hybridization was also indicated in the case of several individuals across various groups. We intend to incorporate the results in the establishment of seed orchards using the selected plus trees, considering the taxonomical, geographical, and genetic distinctiveness of the different groups. Full article

Synthetic promoters are crucial for precise gene expression in transgenic plants, but their rational design is hindered by the difficulty in identifying functional cis-regulatory elements (CREs). In this study, we aimed to develop a systematic approach for discovering tissue-specific cis-regulatory modules (CRMs) and generating functional synthetic promoters in poplar. We performed extensive transcriptomic analysis across various poplar tissues to obtain categorical labels and detected motifs in all gene promoters using known transcription factor binding site (TFBS) position weight matrices. Informative, tissue-specific TFBSs were predicted using a random forest model. Applying this to a root-specific gene, PopRTS1, we identified putative root-specific CRMs. These CRMs were then used to construct synthetic promoters, which were experimentally validated through rapid infiltration and GUS staining assays across different tissues. We successfully identified a root-specific synthetic promoter, PRTS1. Our findings demonstrate that machine learning can effectively decipher regulatory codes from omics data to predict functional CRMs. This work provides a feasible and systematic method for screening and designing tissue-specific synthetic promoters, offering significant potential for advancing targeted gene expression systems in plant biotechnology. Full article

University campus green spaces function as critical microcosms of urban building environments, directly advancing Sustainable Development Goals 3 (Good Health and Well-being) and 11 (Sustainable Cities and Communities) through evidence-based landscape design. Taking a large university in China as the research object, this study integrates virtual reality (VR) simulations with synchronized psychophysiological measurements and perceptual scales to quantify how three planting modes—clustered, scattered, and regular—influence restorative experiences across teaching, living, and administrative areas. Rigorous data processing ensured robustness. The results revealed functional-area-specific restoration pathways: clustered planting enhanced relaxation in living zones, scattered planting elevated vitality in teaching areas, and regular planting reinforced security perception in administrative spaces. A path model was used to elucidate how four-dimensional (4D) landscape indicators (openness, pleasantness, diversity, focus) mediate psychological and physiological responses. Theoretically, this 4D framework translates abstract restorative experiences into operable design dimensions; methodologically, VR-based multi-source measurement offers a replicable technical pathway for scheme verification; practically, it serves as a quantitative tool for planting optimization. Critically, these campus-derived insights offer transferable design principles for enhancing well-being across urban building environments, delivering a replicable VR-assisted framework that directly contributes to sustainable cities through human-centered, evidence-based landscape solutions. Full article

Morus macroura ‘Panzhihua No. 1’ is a dual-purpose cultivar valued for its edible leaves and fruits. Derived from an ancient mulberry tree, it is a unique local germplasm resource. During asexual propagation, M. macroura exhibits sexual variation closely associated with fruit and leaf yield. To explore the molecular mechanisms of sexual dimorphism and its effects on nutritional traits, we integrated transcriptomic and metabolomic analyses of male and female inflorescences and leaves. Key sex-biased genes were enriched in plant hormone signaling, flavonoid biosynthesis, and carbohydrate metabolism pathways. Female plants had elevated expression of ethylene-responsive transcription factor 1 (ERF1), EIN3-binding F-box proteins (EBF1/2), and Chalcone synthase (CHS) genes and higher levels of bioactive flavonoids, including isoquercitrin and kaempferol derivatives. In contrast, male plants had increased expression of gibberellin 20-oxidase (GA20ox) and DELLA genes and accumulated glycosides, which are beneficial for leaf development. These findings reveal how sex-linked metabolic networks shape mulberry tissue functional profiles, providing molecular targets for breeding. Full article

Mulberry, a plant highly valued for medicinal–edible features, was fermented with Lactobacillus plantarum M3 to enhance its bioactive profile. This study conducted a comprehensive evaluation of the antioxidant activity of fermented mulberry juice (FMJ) and identified key metabolites through an integrated approach involving non-targeted metabolomics, network pharmacology, RT-qPCR, and molecular docking. Under optimized conditions (28 °C, pH 5.5, 12°Bx initial sugar content, 48 h and 5% inoculum), fermentation significantly bolstered the antioxidant capacity of MJ. Specifically, superoxide dismutase (SOD) activity increased from 62.41 ± 0.11 to 84.99 ± 0.07 U/mL, while total phenolic content (TPC) surged from 1108.98 ± 2.90 to 2494.17 ± 7.05 mg GAE/L; DPPH radical scavenging activities were improved by 63.09%. Non-targeted metabolomics identified 195 secondary metabolites, primarily comprising alkaloids, flavonoids, and phenolic acids. Among these, protocatechuic acid, Albanin A, and apigenin exhibited significant dynamic shifts, indicating that they may play a pivotal role in regulating antioxidant capacity. Integrated network pharmacology, RT-qPCR validation, and molecular docking further elucidated that Albanin A and Moracin Q likely drive these enhanced antioxidant effects by activating the Nrf2 pathway, suppressing the NF-κB pathway, and upregulating SOD1 expression. These findings provide a theoretical basis for the development of high-potency functional mulberry products. Full article

Accurate and efficient screening of nitrogen-efficient rice varieties is crucial for implementing precision agriculture and achieving green and sustainable development. However, traditional screening methods rely on destructive sampling and chemical analysis, which are inefficient and costly, and thus cannot meet the requirements of large-scale breeding applications. Therefore, this study aims to develop a non-invasive, high-throughput screening method for nitrogen efficiency of rice based on unmanned aerial vehicle (UAV) hyperspectral data and machine learning algorithms. Sixty rice varieties were selected as the target, and principal component analysis (PCA) was used to reduce the dimension of seven key agronomic parameters (such as yield, nitrogen utilization rate, etc.). A comprehensive evaluation index for nitrogen utilization efficiency was constructed, and K-means clustering was used to classify the varieties into three categories: nitrogen-efficient, medium-efficient, and low-efficient varieties. On this basis, four machine learning algorithms (decision tree (DT), random forest (RF), support vector machine (SVM), and K-nearest neighbor (KNN)) were used to establish a variety nitrogen efficiency classification model based on spectral indices. The results showed that the indicators constructed based on PCA and clustering could effectively distinguish different nitrogen-efficient varieties; among the four models compared, the DT model achieved the highest overall performance, with an accuracy of 0.75, precision of 0.80, and F1-score of 0.74. This study confirmed the feasibility of combining UAV hyperspectral data with decision tree models, providing a reliable technical solution for the large-scale, rapid, and non-invasive screening of nitrogen-efficient rice varieties. Full article

Past restoration of hardwood forests prioritized planting of woody vegetation cover, particularly oaks (Quercus spp.). This restoration regime often did not consider other microhabitat components, which failed to restore habitat complexity. Giant cane (Arundinaria gigantea (Walter) Muhl.) was an important microhabitat feature for creating a dense understory structure within the hardwood forest landscape. Many bird species are associated with stands of giant cane (canebrakes) for food, cover, and nesting ground. The decline of canebrakes may reduce nesting and foraging habitat, negatively impacting bird communities. Here, we used a hierarchical multi-species occupancy model to assess how giant cane and its associated overstory forest structure influenced breeding bird occupancy in southern Illinois. Bird surveys were conducted from May to July 2022–2024 at 100 site-years using passive acoustic monitoring. Responses to the vegetation structure (tree density and size) and canebrakes varied among species and nesting guilds (overstory, understory, and ground). Occurrence probabilities of 54% of the bird species increased with the presence of canebrake. We did not find any significant relationships between bird occupancy and vegetation structure and canebrake characteristics. Overall, maintaining a hardwood forest stand with a heterogeneous canopy cover would create variations in light environments, allowing canebrakes to benefit bird species across nesting guilds. Full article

Drought is the most severe natural hazard threatening agricultural production. Mulberry (Morus alba L.) is an important crop for the sericulture industry, and its drought tolerance has been extensively studied. In this study, the phenotypic and physiological responses of two different mulberry tree genotypes (711 and NS8) to drought stress were investigated, with the aim of screening potential nondestructive traits and understand interrelationships. The significant reductions of digital biomass (DB), leaf area (LA), and projected leaf area (PLA) in morphological traits indicated that drought led to a decrease in mulberry yield. The change of color traits R_FarRed and R_NIR were associated with pigments and leaf morphology. Vegetation indexes were also significantly affected by drought stress. Due to their had high correlation coefficients and good linear relationships with yield, DB and LA can be used as yield proxy traits for this measure. Drought-sensitive traits were identified using PCA and correlation analysis, and the results showed that greenness (GR) was a proxy predictor of drought stress. For antioxidant defenses, CAT activity and phenolic compound content were significantly decreased. Metabolomics analysis revealed that genotype 711 exhibited 1691 differential metabolites under drought stress; these mainly comprised amino acids, lipids, and phenolic acids, which were mainly enriched in secondary metabolism and flavonoid biosynthesis. Drought also reprogrammed carbohydrate, secondary compounds, and amino acid metabolism. The results revealed that the phenotypic response of two mulberry trees to drought, as well as the integration of phenotypic traits with metabolic traits, could help us to understand drought tolerance mechanisms and benefit efficient selection and breeding of fitter genotypes. Full article

Pseudomonas syringae pv. syringae (Pss) is the causal agent of bacterial canker, a disease that can result in yield losses, aerial tissue damage, and tree mortality in stone fruits worldwide. Peach, one of the major stone fruit crops, experiences significant yield losses and tree mortality attributed to bacterial canker in the United States. As the second-largest peach-producing state, South Carolina faces direct and significant impacts due to Pss. Early evaluations of peach scion responses to Pss infection have relied primarily on circumstantial field observations in rootstock trials. Although laboratory evaluations in peach have been reported, these studies primarily focused on pathogen virulence testing or small accession sets and did not establish a standardized, scalable detached twig protocol for systematic germplasm phenotyping. The absence of a clearly described laboratory assay has limited reproducible and large-scale evaluation of bacterial canker tolerance in peach. To address this gap, a detached dormant twig assay, previously developed for cherry, was adapted and optimized for peach. Dormant shoots from nine peach accessions were cut into 10 cm segments, surface-sterilized, and inoculated with a Pss suspension prepared in 10 mM MgCl₂ buffer or with the buffer alone. After six weeks of incubation, inner bark lesion size was evaluated visually and quantified using ImageJ. A newly developed visual rating scale was established and compared with quantitative lesion measurements. Spearman correlation analysis showed strong positive correlations between visual disease scores and ImageJ-based lesion measurements across two independent replicates (ρ = 0.80–1.00, p < 0.01), while shoot segment diameter showed weak-to-moderate negative correlations with disease severity. This adapted and consolidated dormant twig assay provides a practical, reproducible, and scalable method for phenotyping bacterial canker tolerance in peach and supports future germplasm screening and breeding efforts. Full article

Background: Apples and pears, as important economic fruit crops, are frequently threatened by various diseases, including Valsa canker. Given the numerous advantages of disease resistance breeding, the identification of key resistance genes is particularly important. This study aimed to identify the “Duli-G03” (Pyrus betulifolia) resistance gene PbeZFP3 and clarify its regulatory mechanism in disease resistance via JA/SA pathways, providing a theoretical basis for resistant breeding. Results: In this study, we identified a C2H2-type transcription factor, PbeZFP3, in the Valsa canker-resistant rootstock “Duli-G03”. Expression analysis revealed that PbeZFP3 is induced by both Valsa pyri (Vp) and Vp metabolites (VpM). Transient expression in pear and apple fruits and stable expression in suspension cells confirmed that PbeZFP3 positively regulates Valsa canker resistance. Meanwhile, PbeZFP3 not only enhances the resistance of “Duli-G03” cells to Botrytis cinerea infection, but may also act as a negative regulator against Colletotrichum fructicola. The overexpression of PbeZFP3 in “Duli-G03” significantly upregulated the expression of genes related to jasmonic acid (JA) and salicylic acid (SA) signaling. Conclusions: These findings demonstrate that the jasmonic acid (JA) and salicylic acid (SA) signaling pathways are involved in the enhanced Valsa canker resistance conferred by PbeZFP3 overexpression. A deeper understanding of this host resistance mechanism will provide theoretical support for breeding strategies aimed at developing disease-resistant fruit trees. Full article

The carapace of the Chinese soft-shelled turtle (Pelodiscus sinensis) is rich in collagen and stands as a crucial economic trait for assessing its quality, as well as a key indicator for selective breeding. However, current studies on the mechanisms underlying collagen deposition in the carapace remain severely limited, significantly hindering progress in selective breeding. Here, the Col1a2 gene of P. sinensis was molecularly characterized for the first time. Analysis of gene structure, phylogenetic tree, and amino acid sequence homology revealed that Col1a2 is relatively conserved among tetrapods but divergent from fishes. Collinearity analysis identified the BET1-COL1A2-CASD1-SGCE gene block shared across all 14 representative vertebrates and found that the Col1a2 is located on the Z chromosome of Thamnophis elegans. Tissue expression analysis showed that Col1a1 was highly expressed in the heart, gonad, and lung. Additionally, Col1a1 expression levels markedly increased during carapace development, exhibiting a strongly positive correlation with the changes in collagen content of the carapace. In situ hybridization results revealed strong signal for the Col1a2 transcripts in fibroblasts of the dermal layer of P. sinensis carapace. Knockdown of the Col1a2 gene in the carapace cells of P. sinensis significantly reduced collagen content. Transcriptome analysis following Col1a2 knockdown identified several differentially expressed genes associated with collagen deposition, including Fbln2, IL-11, and Rspo4, as well as significantly enriched pathways such as the JAK-STAT signaling pathway, the apelin signaling pathway, and the Hippo signaling pathway. Our findings offer a molecular basis for elucidating the mechanisms of collagen deposition in the carapace of P. sinensis, while also supplying a potential target for the selective breeding of collagen-rich strains of P. sinensis. Full article

Pine wood nematode (PWN, Bursaphelenchus xylophilus) is fatal to the pine trees around the world. Its northward and westward expansion in China endangers Larix spp., yet its molecular response remains understudied. We conducted transcriptomic analysis (RNA-seq) on three economically important larch species (Larix principis-rupprechtii, L. olgensis, and L. kaempferi) infected by geographically distinct PWN isolates (northern Fushun and southern Changde strains) at 1 and 3 days post-inoculation. Comparative RNA-seq analysis of 36 samples revealed that genes such as oxidative stress, and secondary metabolite production were differentially expressed in Larix spp. upon infection by the PWNs. Furthermore, compared to the Changde strain, infection with the Fushun PWN strain can elicit a consistently stronger and more distinct transcriptional defense response across all tested larch species. These results provide insights into the molecular mechanisms of plant defense against PWNs, offering genetic target for resistance breeding and informing the development of targeted control measures against this pathogen. Full article