Search Results (281)

Rice (Oryza sativa L.) is one of the major food crops. Yield and quality are affected by premature leaf senescence, a complex and tightly regulated developmental process. To elucidate the molecular regulatory mechanism controlling rice leaf senescence, the integrative transcriptome, metabolome and weighted gene co-expression network analysis (WGCNA) of flag leaves in five development stages (FL1–FL5) was performed. In this study, a total of 9412 differential expressed genes (DEGs) were identified. To further mine DEGs related to leaf senescence, a total of five stage-specific modules were characterized by WGCNA. Among them, two modules displayed continuous down-regulated and up-regulated trends from stages FL1 to FL5, which were considered to be highly negatively and positively correlated with the senescence trait, respectively. GO enrichment results showed that the genes clustered in stage-specific modules were significantly enriched in a vast number of senescence-associated biological processes. Furthermore, large numbers of senescence-related genes were identified, mainly participating in transcription regulation, hormone pathways, degradation of chlorophyll, ROS metabolism, senescence-associated genes (SAGs), and others. Most importantly, a total of 40 hub genes associated with leaf senescence were identified. In addition, the metabolome analysis showed that a total of 309 differential metabolites (DMs) were identified by WGCNA. The integrative transcriptome and metabolome analysis identified a key hub gene OsBELH4A based on the correlation analysis conducted between 40 hub genes and 309 DMs. The results of function validation showed that OsBELH4A overexpression lines displayed delayed leaf senescence, and significantly increased grain number per plant and grain number per panicle. By contrast, its knockout lines displayed premature leaf senescence and reduced grain yield. Exogenous hormone treatment showed that OsBELH4A significantly responded to SA and auxin. These findings provide novel insights into leaf senescence, and further contribute to providing genetic resources for the breeding of crops resistant to premature senescence. Full article

Soybean (Glycine max (L.) Merr.) is a vital crop for the global supply of protein and oil, with its growth and development being regulated by genetic, hormonal, and environmental factors, particularly light and hormone signaling. The Small Auxin-Up RNA (SAUR) gene family plays a crucial role in plant growth regulation; however, the molecular mechanisms by which GmSAUR46 integrates photosynthesis and hormonal networks in soybean remain unclear. In this study, we focused on GmSAUR46b (Glyma.19G182600.1) and employed CRISPR/Cas9-mediated knockout and 35S-driven overexpression lines, alongside wild-type soybean (cv. Williams 82), to investigate its function. RNA sequencing (RNA-Seq) was conducted on shoot apical meristems, stems, and leaves at three developmental stages (V1, V2, V3), followed by transcriptomic analyses, including differential gene expression (DEG) identification and functional enrichment (GO, KEGG, KOG). Anatomical studies using paraffin sectioning and scanning electron microscopy (SEM) assessed the leaf midrib thickness and stem trichome density under varying light conditions. The transcriptomic results revealed DEGs enriched in pathways related to cell wall metabolism, hormone response, and photosynthesis. Anatomical analyses demonstrated that GmSAUR46b specifically regulates the leaf midrib thickness and stem trichome density in a light-dependent manner: under shade, the overexpression lines exhibited increased midrib thickness and trichome density, whereas the knockout lines showed reduced trichome density. Additionally, novel transcripts associated with stress resistance, hormone metabolism, and photosynthesis were identified, expanding the known soybean gene repertoire. Collectively, GmSAUR46b functions as a central hub integrating light signals with hormone and cell wall pathways to modulate soybean growth, particularly leaf and stem traits. This study advances understanding of SAUR gene function in soybean and provides valuable insights for molecular breeding aimed at improving adaptability and yield under diverse environmental conditions. Full article

Camphora officinarum Nees is a significant economic tree because of its aromatic, medicinal, and ornamental attributes. The diverse flavonoids present within the leaves of C. officinarum have been neglected for an extended period, hindering a comprehensive understanding of the molecular mechanisms responsible for color transformation and resistance to adverse environmental conditions. In this study, multi-omics analyses were conducted to systematically compare the relative contents of flavonoid metabolites and the expression profiles of flavonoid-related genes across three developmental stages of C. officinarum leaves. A total of 175 flavonoid compounds were detected via metabolomics, with flavonols being the most abundant. Through weighted gene co-expression network analysis, 25 key DEGs encoding CHS, DFR, FLS, ANS, F3′H, and LAR genes are predicted to be involved in anthocyanin biosynthesis for color change during leaf development. Notably, ten MYB, seven bHLH, and three ERF factors are potentially implicated in the regulation of key genes, underscoring their significant contributions to the color mechanisms underlying flavonoid biosynthesis. Other flavonoids, e.g., apigenin, isorhamnetin glycosides, sakuranetin, and sakuranin, may facilitate the adaptation of C. officinarum for protective purposes against adverse environmental conditions. These findings lay a theoretical foundation for resource exploration and the ornamentation improvement of C. officinarum. Full article

Vitellaria paradoxa (shea tree) is an economically and medicinally important species indigenous to sub-Saharan Africa. Although the species holds substantial value, domestication efforts have been constrained, primarily due to the absence of efficient propagation alternatives, especially for the East African subspecies (V. paradoxa subsp. nilotica) which remains understudied in tissue culture research. This study investigated the influence of leaf explant developmental stage and media composition on callogenesis and embryogenic potential in V. paradoxa subsp. nilotica. Thus, leaf explants from six distinct growth stages were cultured on Murashige and Skoog (MS) media supplemented with various concentrations of 2,4-D, TDZ, NAA, and BAP. Callogenesis was significantly influenced by explant age, media strength, and specific PGR combinations. Results revealed that explants from Stage III (11–15 days) and Stage IV (16–20 days) exhibited the highest callus induction rates (up to 100%), particularly on half-strength MS media containing 2.0 mg/L 2,4-D and 0.5–1.0 mg/L TDZ. Histological analysis suggests that varying responses at the different stages relate to chloroplast distribution, trichome density/orientation, and vascular tissue maturity. Pro-embryogenic structures were successfully induced, representing a developmental milestone with strong prospects for advanced stages of differentiation. The findings also emphasize the importance of explant physiology and media formulation in developing regeneration protocols for V. paradoxa from leaf explants. Full article

Primula veris L. (cowslip) is a medicinal plant traditionally used for respiratory ailments, with its therapeutic properties attributed to triterpene saponins and phenolic glycosides found in the roots and the aerial parts. The present study aimed to investigate the impact of different LED light spectra (red, blue, red:blue, and white fluorescent as a control) on P. veris’s relative growth rate, physiology, and secondary metabolite production to optimize its cultivation under controlled conditions. The results demonstrate that the light quality significantly influences P. veris’s growth characteristics, physiology, and secondary metabolite production. Red light promoted leaf expansion, while the red:blue LED combination enhanced the root fresh weight and concentration of total chlorophylls and carotenoids in primrose leaves in comparison to the white fluorescent and solitary red light, respectively. Red light significantly increased the accumulation of key secondary metabolites (primeverin, primulaverin, and primulic acids) in roots during the flowering phase compared with the white inflorescent. In addition, the concentration of phenolic compounds was strongly influenced, showing a decrease between the vegetative and the flowering stage of development. Finally, this study highlights the potential of tailored LED lighting to optimize P. veris cultivation, enhancing both biomass and the production of valuable bioactive compounds, taking into account the developmental stage of the plants. Full article

Glycine betaine (GB) is a compatible solute that enhances plant tolerance to abiotic stresses, yet its role in fruit crops remains insufficiently explored. This study assessed whether GB improves drought tolerance in Passiflora edulis Sims f. flavicarpa, a crop sensitive to irregular rainfall. A 3 × 2 × 2 factorial design was employed, combining three drought levels (control, mild, and severe), two propagation methods (seedlings and cuttings), and two GB treatments (0 and 100 mM), with 60 plants and five replicates. Plants were grown under controlled conditions, and irrigation was adjusted to maintain target field capacities. Chlorophyll content was monitored daily, and agronomic and physiological traits were measured after 45 days. GB application influenced leaf water dynamics and stress responses. Cuttings generally showed clearer improvements in drought tolerance when treated with GB, while seedlings exhibited more variable outcomes. These differences appear linked to the propagation method and developmental stage as cuttings were at a more advanced phase, whereas seedlings remained vegetative. Overall, the results demonstrate that exogenous GB can enhance drought tolerance in passion fruit, although its effectiveness is propagation-dependent and context-specific, highlighting the need to tailor its application to cultivation practices. Full article

The large, white paired bract is a unique trait, as well as the most intriguing feature of the dove tree (Davidia involucrata). However, the mechanisms underlying bract development remain unclear. Our previous comparative transcriptome analysis concerning Davidia bracts at different developmental stages has identified a number of bract-specific genes. Among these, the genes encoding PRPs (proline-rich proteins) show dramatic expression variation, indicating the participation of this gene family in bract development. In this study, we screened the whole Davidia genome and identified twelve Davidia PRP (DiPRP) genes, showing obvious expression variation during bract development, with some upregulated up to 100-fold at the fast-developing stage. These PRP genes are evenly distributed on seven Davidia chromosomes. The cis-element composition of the promoter regions of the DiPRPs demonstrates that these genes might be controlled by phytohormones (especially ABA, GA, and MeJA), light, and the circadian clock, which is consistent with the environmental cues during Davidia bract development. Synteny analysis indicated that the PRP genes from the Davidia genome have higher collinearity with naturally bracted plants, such as Antirhonum majus and Bougainvillea glabra, but lower collinearity with non-bracted species. Our results suggest that high expression of certain PRP genes, specifically in bracts, might be critical for leaf metamorphosis. Full article

Intra-specific variation in functional traits and their inter-relationships reflect how plants allocate resources, adapt, and evolve in response to environmental changes. This study investigated eight functional traits—leaf area (LA), specific leaf area (SLA), leaf dry matter content (LDMC), chlorophyll content (CHL), leaf nitrogen content (LNC), leaf phosphorus content (LPC), twig tissue density (TTD), and wood density (WD)—in Cunninghamia lanceolata plantations of three stand ages (15, 30, and 50 years), using a space-for-time substitution approach. We examined differences in trait values, intra-specific variation, and trait correlations across forest ages and diameter classes. The results showed that (1) Functional traits exhibited varying degrees of intra-specific variation, with LA having the highest coefficient of variation (21.66%) and LPC is lowest (9.31%). (2) Forest age had a stronger influence on trait variation than diameter class, with all traits differing significantly across ages, while only WD varied significantly among diameter classes. (3) PC1 (25.5%) and PC2 (19.4%) together explained approximately 44.9% of the total variation, with PC1 primarily reflecting functional trait changes driven by forest age. PCA results showed that LA and CHL tended to exhibit higher values in young forests, whereas SLA, LDMC, LPC, and LNC had relatively higher values in mature forests. This pattern suggests a shift in functional trait expression from resource acquisition to resource conservation strategies with increasing forest age. (4) Significant positive correlations between LNC and LPC, and negative correlations between SLA and LDMC, were observed in most groups, except in large-diameter trees at the over-mature stage. C. lanceolata adjusts trait combinations to enhance fitness across developmental stages. Juvenile trees adopt traits favoring efficient light and nutrient use to support rapid growth and competition. Middle-aged trees prioritize balanced water and nutrient use to maintain productivity and resist disturbances. Mature trees focus on sustained resource use and offspring protection to support ecosystem stability and regeneration. These findings reveal age-specific adaptive strategies and provide insights into the coordination and trade-offs among traits in response to environmental conditions. Full article

Lithocarpus litseifolius, a traditional sweet tea rich in dihydrochalcones, relies on plant nutrients for secondary metabolite accumulation. However, nutrient distribution patterns during leaf development and its relationship with secondary metabolites remain inadequately characterized. This study examined mineral elements, carbon and nitrogen metabolites, and primary dihydrochalcones in L. litseifolius leaves at various developmental stages, and analyzed their interrelationships. Mineral nutrients such as phosphate (P), potassium (K), magnesium (Mg), zinc (Zn), boron (B), and copper (Cu), along with trilobatin, were most abundant in the youngest leaves. Conversely, calcium (Ca), iron (Fe), sulfur (S), manganese (Mn), selenium (Se), sugars, soluble protein, amino acids, chlorophyll, and carotenoids predominantly accumulated in old leaves, paralleling the distribution of phlorizin. Nitrogen (N) and molybdenum (Mo) concentrations were higher in mature leaves. In young leaves, P, K, Mg, S, Mn, Zn, and B positively correlated with phlorizin and trilobatin, while N, chlorophyll, carotenoids, and fructose correlated negatively. Trilobatin was the primary contributor to hydroxyl radical (·OH) scavenging capacity. Redundancy analysis highlighted N, P, Mg, B, Zn, Cu, Fe, Mo, and Se as key mineral nutrients influencing phlorizin and trilobatin accumulation. These findings offer insights for mineral nutrient management and effective utilization of L. litseifolius. Full article

Plant disease segmentation has achieved significant progress with the help of artificial intelligence. However, deploying high-accuracy segmentation models in resource-limited settings faces three key challenges, as follows: (A) Traditional dense attention mechanisms incur quadratic computational complexity growth (O($n^{2}d$)), rendering them ill-suited for low-power hardware. (B) Naturally sparse spatial distributions and large-scale variations in the lesions on leaves necessitate models that concurrently capture long-range dependencies and local details. (C) Complex backgrounds and variable lighting in field images often induce segmentation errors. To address these challenges, we propose Sparse-MoE-SAM, an efficient framework based on an enhanced Segment Anything Model (SAM). This deep learning framework integrates sparse attention mechanisms with a two-stage mixture of experts (MoE) decoder. The sparse attention dynamically activates key channels aligned with lesion sparsity patterns, reducing self-attention complexity while preserving long-range context. Stage 1 of the MoE decoder performs coarse-grained boundary localization; Stage 2 achieves fine-grained segmentation by leveraging specialized experts within the MoE, significantly enhancing edge discrimination accuracy. The expert repository—comprising standard convolutions, dilated convolutions, and depthwise separable convolutions—dynamically routes features through optimized processing paths based on input texture and lesion morphology. This enables robust segmentation across diverse leaf textures and plant developmental stages. Further, we design a sparse attention-enhanced Atrous Spatial Pyramid Pooling (ASPP) module to capture multi-scale contexts for both extensive lesions and small spots. Evaluations on three heterogeneous datasets (PlantVillage Extended, CVPPP, and our self-collected field images) show that Sparse-MoE-SAM achieves a mean Intersection-over-Union (mIoU) of 94.2%—surpassing standard SAM by 2.5 percentage points—while reducing computational costs by 23.7% compared to the original SAM baseline. The model also demonstrates balanced performance across disease classes and enhanced hardware compatibility. Our work validates that integrating sparse attention with MoE mechanisms sustains accuracy while drastically lowering computational demands, enabling the scalable deployment of plant disease segmentation models on mobile and edge devices. Full article

The miR156 family, crucial for phase transition and stress responses in plants, remains functionally uncharacterized in the ecologically and commercially important gymnosperm Larix kaempferi. This study systematically investigated L. kaempferi miR156 through phylogenetic analysis, structural prediction, expression profiling during somatic embryogenesis, and heterologous functional validation in Arabidopsis. Four MIR156 family members (LkMIR156s) were identified in Larix kaempferi, each with a characteristic stem-loop structure and highly conserved mature sequences. Computational predictions indicated that these LkMIR156s target four LkSPL family genes (LkSPL1, LkSPL2, LkSPL3, and LkSPL9). qRT-PCR analysis showed that mature LkmiR156s expression remained relatively low during early embryonic development but was significantly upregulated at the cotyledonary stage (21–42 days). Precursor transcript levels peaked earlier (around 28 days) than those of the mature LkmiR156, which remained highly expressed throughout cotyledonary embryo development. This sustained high expression coincided with cotyledon morphogenesis and embryonic dormancy. Functional validation via heterologous overexpression of LkMIR156b1 in Arabidopsis resulted in increased rosette leaf numbers (42.86% ± 6.19%) and individual leaf area (54.90% ± 6.86%), phenotypically consistent with the established role of miR156 in growth regulation. This study reveals the temporal expression dynamics of LkmiR156s during L. kaempferi somatic embryogenesis and its coordinated expression patterns with cotyledon development and embryonic dormancy. The functional conservation of the miR156-SPL module was confirmed in a model plant, providing key molecular insights into the developmental regulatory network of conifers. These findings offer potential strategies for optimizing somatic embryogenesis techniques in conifer species. Full article

This study investigated the effects of light intensity regulation on yield and energy efficiency during potato pre-basic seed propagation in plant factories. Using virus-free ‘Favorita’ potato seedlings as experimental material, gradient light intensities (200, 300, and 400 μmol·m²·s⁻¹) were applied at four developmental stages: the seedling stage (SS), tuber formation stage (TFS), tuber growth stage (TGS), and harvest stage (HS), to explore the physiological mechanisms of stage-specific light intensity regulation and energy utilization efficiency. The results revealed that: (1) The per-plant tuber yield of the high yield group reached 72.91 g (T59 treatment), representing a 25% increase compared to the medium yield group and a 168% increase compared to the low yield group. Additionally, the high yield group exhibited superior leaf area, photosynthetic rate, and accumulation of sucrose and starch. (2) The impact of light intensity on tuber development exhibited stage specificity: low light intensity (200 μmol·m⁻²·s⁻¹) during TFS promoted early tuber initiation, while a high light intensity (400 μmol·m⁻²·s⁻¹) enhanced tuber formation efficiency. Increasing the light intensity during TGS facilitated the accumulation of sucrose and starch in tubers. (3) Energy use efficiency (EUE) increased significantly with yield, with the high yield group reaching 3.2 g MJ⁻¹, representing 52% and 88% improvements over the medium yield (2.1 g MJ⁻¹) and low yield (1.7 g MJ⁻¹) groups, respectively. A “stage-specific precision light supplementation” strategy was proposed, involving moderate light reduction (200 μmol·m⁻²·s⁻¹) during TFS and light enhancement (300 μmol·m⁻²·s⁻¹) during TGS to coordinate source-sink relationships and optimize carbohydrate metabolism. This study provides a theoretical basis for efficient potato production in plant factories. Full article

Purple totomoxtle (maize husk) in native maize represents a phenotypic trait of cultural and agronomic significance within traditional Mesoamerican agroecosystems. This study evaluated the phenotypic expression of anthocyanins in vegetative and reproductive tissues of ten native maize genotypes, including inter-parental crosses derived from both pigmented and non-pigmented lines. Field trials were conducted under rainfed conditions in Chiapas, Mexico. Visual and quantitative assessments included pigmentation intensity, chlorophyll and carotenoid content, ear traits and appearance, grain health, and yield performance. Genotypes exhibiting the purple phenotype showed consistent pigment accumulation in stems, nodes, leaf sheaths, tassels, and bracts (totomoxtle), with statistically significant differences compared to non-pigmented controls. Anthocyanin content in totomoxtle increased by 30% during late developmental stages, whereas chlorophyll and carotenoid levels peaked during early vegetative growth. Pigmented materials displayed healthier grain, enhanced ear appearance, and higher yields, with the JCTM × LLMJ cross reaching 6.60 t ha⁻¹. These findings highlight the functional value of purple totomoxtle and its potential in agroecological programs aimed at resilience, genetic conservation, and integral resource utilization, providing useful criteria such as stable pigment expression and superior yield to guide sustainable reproduction strategies. Full article

(1) Background: High temperatures and water scarcity, intensified by climate change, present major challenges to Mediterranean viticulture. In this study morphological, anatomical, and physiological responses of leaves at two developmental stages of Vitis vinifera L. cv. Assyrtiko were examined. (2) Methods: Young expanding and fully expanded leaves of two-year-old grapevines grown in pots in a controlled growth chamber, grown in soil in an open-air vineyard, and an adjacent greenhouse on Aegina Island (Greece), were used. The plants were subjected to water deficit (WD), elevated temperature (ET), and combined water deficit and elevated temperature (WD_ET) conditions for four months, and compared with control plants (C). (3) Results: Stress conditions caused contrasting effects on specific leaf area (SLA), which declined in young expanding leaves, except for a significant increase under elevated temperatures, while it increased in fully expanded leaves exposed to stress treatments. Concerning the anatomical traits, the thickness of spongy and palisade parenchyma did not change in young expanding leaves exposed to the three stress treatments, but increased in fully expanded leaves exposed to WD_ET. Metabolic traits (phenolic compounds, soluble sugars, and starch content) further highlighted these differences. (4) Conclusions: The findings reveal distinct stress responses between young expanding and fully expanded leaves of the grapevine Assyrtiko, underscoring the influence of water deficit and elevated temperatures on leaf developmental stage. Full article

Broad bean is one of the most important leguminous crops worldwide. However, its productivity is greatly affected by the infestation of Aphis fabae and Aphis craccivora (Hemiptera: Aphididae). The main objective of the current study was to identify the most susceptible phenological stages of the broad bean variety (Histal) against black aphids’ herbivory. This had been achieved through an evaluation of plant resistance mechanisms such as antixenosis and antibiosis. The results regarding an antixenosis test revealed that the four tested phenological stages of V. faba did not have a significant effect on the preference of A. craccivora and A. fabae towards the crop plant. Overall, a slightly higher number of adults settled on the three and four unfolded leaves’ stage of the crop plant. Similarly, the highest number of developed embryos were found in the four leaves’ stage of the crop, and the lowest in the second leaf stage. The adult body size of A. craccivora was slightly larger in the case of the three unfolded leaves. Furthermore, the maximum body size of A. fabae adults was recorded in the case of the first unfolded leaf stage crop. Linear correlations between the biological parameters for both species revealed only one significant relationship between developed and total embryos for A. craccivora. The results of the current study highlight the need to protect broad bean crops against infestations of black aphids, i.e., A. craccivora and A. fabae. This is essential for reducing direct damage and preventing the transmission of phytoviruses. However, future studies should aim to evaluate the susceptibility of all developmental phenological stages of the crop against black aphids to mitigate potential crop losses. Full article