Search Results (68)

Background: Phoebe zhennan and Phoebe chekiangensis are valuable evergreen trees recognized for their unique aromas and ecological significance, yet the organ-related distribution and functional implications of aroma-active volatiles remain insufficiently characterized. Methods: In this study, we applied an integrated GC-MS-based volatile metabolomics approach combined with a relative odor activity value (rOAV) analysis to comprehensively profile and compare the volatile metabolite landscape in the seeds and leaves of both species. Results: In total, 1666 volatile compounds were putatively identified, of which 540 were inferred as key aroma-active contributors based on the rOAV analysis. A multivariate statistical analysis revealed clear tissue-related separation: the seeds were enriched in sweet, floral, and fruity volatiles, whereas the leaves contained higher levels of green leaf volatiles and terpenoids associated with ecological defense. KEGG pathway enrichment indicated that terpenoid backbone and phenylpropanoid biosynthesis pathways played major roles in shaping these divergent profiles. A Venn diagram analysis further uncovered core and unique volatiles underlying species and tissue specificity. Conclusions: These insights provide an integrated reference for understanding tissue-divergent volatile profiles in Phoebe species and offer a basis for fragrance-oriented selection, ecological trait evaluation, and the sustainable utilization of organ-related metabolic characteristics in breeding and conservation programs. Full article

Anthocyanins, crucial water-soluble pigments in plants, determine coloration in floral and fruit tissues, while fulfilling essential physiological roles in terms of plant growth, development, and stress adaptation. The biosynthesis of anthocyanins is transcriptionally regulated by WRKY factors, one of the largest plant-specific transcription factor families. Euscaphis japonica is an East Asian species, prized for its exceptionally persistent butterfly-shaped fruits that undergo pericarp dehiscence, overturning, and a color transition to scarlet red. This species represents an ideal system for studying anthocyanin regulation. However, the mechanisms by which WRKY transcription factors orchestrate anthocyanin accumulation during this process remain unknown. In this study, we identified 87 WRKY genes (EjaWRKYs) from the E. japonica genome. Phylogenetic analysis was used to classify these genes into three primary groups, with five subgroups, revealing conserved gene structures and motif compositions, supported by collinearity and comparative synteny analyses. Crucially, ten EjaWRKYs exhibited peak expression during the mature fruit stages, showing positive correlations with key anthocyanin biosynthesis genes. Functional validation through the use of transient transactivation assays in Nicotiana benthamiana confirmed that the five selected EjaWRKYs bind W-box elements and strongly activate reporter gene expression. Our results reveal EjaWRKYs’ regulation of anthocyanin accumulation in E. japonica fruit, provide the first comprehensive WRKY family characterization of this species, and establish a foundation for manipulating ornamental traits in horticultural breeding. Full article

Lonicera japonica Thunb. is a traditional Chinese medicinal herb whose floral buds are the primary source of pharmacological compounds that require manual harvesting. As a result, its floral bud duration, determined by the opening time, is a key determinant of both quality and economic value. However, the genetic mechanisms controlling floral bud duration remain poorly understood. In this study, we employed population structure analysis and molecular experiments to identify candidate genes associated with this trait. The improved cultivar Beihua No. 1 (BH1) opens its floral buds significantly later than the landrace Damaohua (DMH). Exogenous application of methyl jasmonate (MeJA) to BH1 indicated that jasmonate acts as a negative regulator of floral bud duration by accelerating floral bud opening. A genome-wide selection scan across 35 germplasms with varying floral bud durations identified the transcription factor LjWRKY50 as the causative gene influencing this trait. The dual-luciferase reporter assay and qRT-PCR experiments showed that LjWRKY50 activates the expression of the jasmonate biosynthesis gene, LjAOS. A functional variant within LjWRKY50 (Chr7:24636061) was further developed into a derived cleaved amplified polymorphic sequence (dCAPS) marker. These findings provide valuable insights into the jasmonate-mediated regulation of floral bud duration, offering genetic and marker resources for molecular breeding in L. japonica. Full article

Camellia azalea is an endemic species within the genus Camellia that exhibits the trait of summer flowering, which is of significant ornamental and research value. Nevertheless, research on the regulatory mechanisms of flower formation in C. azalea is still limited, so in this study, transcriptome sequencing and analysis of endogenous hormone contents were conducted at three distinct growth stages: floral induction, floral organ maturation, and anthesis. Illumina sequencing yielded a total of 20,643 high-quality unigenes. Comparative analyses of representative samples from the three growth stages identified 6681, 1925, and 8400 differentially expressed genes (DEGs), respectively. These DEGs were further analyzed for functional enrichment using the GO and KEGG databases. Additionally, core genes from each flowering pathway underwent expression pattern analysis and network diagram construction. This revealed that the flower development process in C. azalea is linked to the specific expression of the genes involved in the photoperiod, temperature, and autonomous pathways and is subject to comprehensive regulation by multiple pathways. Further analysis of the dynamic trends of five endogenous hormone contents and plant hormone signal transduction genes revealed significant differences in the requirements of endogenous hormones, such as gibberellins and indoleacetic acid, by C. azalea at distinct growth stages. Additionally, the majority of genes on the phytohormone signal transduction pathway demonstrated a high correlation with the changes in the contents of each hormone. The present study integrates physiological and molecular approaches to identify key genes and metabolic pathways that regulate the summer flowering of C. azalea, thereby laying a theoretical foundation for further investigations into its flowering mechanism and related functional genes. Full article

Urban environments pose challenges for pollinators due to habitat loss and limited floral resources. However, green infrastructure, particularly street and ornamental trees, can play a critical role in supporting urban pollinator communities. In this study, we evaluated nectar volume, sugar content, and amino acid composition across eight urban tree species commonly planted in South Korea. Using standardized productivity metrics at the flower, tree, and hectare scales, we compared their nutritional contributions. Our results revealed substantial interspecific differences in nectar quantity and composition. Tilia amurensis, Heptacodium miconioides, Aesculus turbinata, and Wisteria floribunda exhibited high nectar yields or amino acid productivity, whereas species such as Cornus kousa, though lower in nutritional yield, may offer complementary value due to their distinct flowering periods or other phenological traits. These findings underscore the importance of selecting tree species not only for aesthetic value but also for ecological function, providing an evidence-based approach to pollinator-friendly urban biodiversity planning and landscape management. Full article

This study investigates the seasonal and floral phenology, breeding strategies, and floral morphology of Azorina vidalii, an Azorean endemic Campanulaceae with hermaphroditic, protandrous flowers, dichogamy and secondary pollen presentation. Seasonal phenology was recorded in four field populations and floral phenology in a garden population. Reproductive strategies were assessed via controlled hand pollinations in one field population. Floral morphometrics were analysed using 23 floral and five pollen traits from 121 flowers across fourteen populations throughout the Azores archipelago. Non-parametric and parametric tests, discriminant analysis, and reproductive indices were used to infer answers to this study’s goals. Results showed that temperature and humidity influenced vegetative and reproductive phenophases. The male phase was shorter than the female, likely due to pollen dynamics, and some functional overlap suggested incomplete dichogamy. Geographic variation in floral traits indicated morphological differentiation across subarchipelagos, presumably linked to environmental factors or isolation. Reproductive indices suggested a mixed mating system, partial self–incompatibility and signs of inbreeding depression. Fertilisation was absent without pollinators, and spontaneous selfing was excluded due to an absence of pollen–pistil contact during stigma retraction. These findings contribute to understanding the reproductive biology and morphologic variation in A. vidalii. The implications of these findings for the conservation of this insular plant are discussed. Full article

Concerns about a global decline in pollinators have called for more knowledge about the drivers of wild pollinator abundance and diversity in agroecosystems. Maintaining flowering plants in agricultural field margins is often recommended as a cost-effective and efficient method of offering habitat for wild pollinator conservation. This research involved a three-year, multi-farm study, examining Mediterranean cereal field margins in order to investigate which general and functional characteristics of margin plant communities were important for sustaining wild bee abundance, diversity, community evenness and functional diversity. Wild bees were collected and identified to genus, and a database was compiled listing the morpho-physiological features and behaviours of the observed genera. A database was also compiled of the flowering plant species observed and relevant trait values. General and generalized linear models indicated that margins with a higher percentage of trees and shrubs and higher floral richness displayed positive effects on wild bee diversity and visits to flowers in Mediterranean cereal agroecosystems. They also indicated that high plant functional diversity, in terms of flower colour and morphology, as well as high nectar accessibility, were important to encourage bee visits and community evenness within wild bee assemblages in these field margins. This study stresses the importance of maintaining protected field margins and, when necessary to restore their functionality, sowing floral mixtures with diverse native species, including trees and shrubs, and providing plenty of accessible nectar and a diverse assortment of colours and shapes. Full article

In plants, SPL is a distinct family of transcription factors. Its protein structure possesses a highly conserved SBP domain comprising two zinc finger structures and nuclear localization regions, and microRNAs (miR156) control the transcriptional expression of the majority of SPL genes. SPLs are key TFs in regulating organ morphogenesis, phase transition/floral induction, and yield-related traits in agronomic and horticultural crops. These biomolecules have been functionally characterized for their role in augmenting plant responses to abiotic and biotic stresses. Present research gaps and viewpoints are addressed herein. Using these extensive data, researchers can more comprehensively understand how SPL genes modulate agronomic features in different ways. Full article

Agricultural intensification has led to biodiversity loss and compromised ecosystem services, necessitating sustainable pest management strategies. This study evaluates the efficacy of wildflower strips (WFS) in enhancing natural enemy communities and suppressing pest activity in rice-wheat rotation landscapes of eastern China. An experiment compared WFS (10-species mixtures) with natural grass strips (CK) across biodiversity, functional traits, and pest dynamics. WFS significantly increased parasitic wasp α-diversity (species richness: +195.5%, activity density: +362.0%) and suppressed pest (Armadillidium vulgare) populations by 68%, primarily through female-biased sex ratios and functional trait shifts. Key species like Lindenius mesopleuralis and Ectemnius continuus emerged as indicators of WFS habitats. Spider communities showed no β-diversity differentiation but exhibited functional guild shifts (e.g., web-building specialists). Plant community composition, particularly floral resource availability and phenological continuity, drove natural enemy assembly and pest regulation, outperforming the CK group in rare species conservation. Our findings highlight WFS as a precision tool for enhancing pest control through targeted plant selection and trait-mediated interactions. This study advances the understanding of habitat-driven pest regulation, providing a framework for optimizing ecological intensification in agroecosystems. Full article

Ethylene-insensitive 3/ethylene-insensitive 3-like (EIN3/EIL) transcription factors are central regulators of ethylene signaling and stress adaptation in plants. However, their roles in Osmanthus fragrans, a globally cherished ornamental and aromatic plant with significant economic value, remain poorly characterized. Here, we identified nine OfEIL genes across eight chromosomes in the O. fragrans “Liuye Jingui” genome. Conserved motif analysis revealed core domains (Motif1/2/4/7), and promoter cis-elements highlighting hormone-related, stress-related, and growth-related regulatory potential. During late flowering stages, six OfEILs (3/4/5/6/7/9) were significantly upregulated. Under 5-azacytidine (AZA, a DNA demethylation agent), OfEIL2 and OfEIL7 were downregulated, whereas the ETH treatment activated OfEIL3/7/8/9. Strikingly, OfEIL7 exhibited dual regulatory roles, correlating strongly with natural flowering progression, AZA-induced demethylation, and ETH responses. Functional divergence was observed in petal senescence, with OfEIL2–5 and OfEIL7–9 showing stage-specific and tissue-specific expression patterns. These results position OfEIL7 as a key hub integrating epigenetic and hormonal signals to modulate floral longevity and stress adaptation. Our study provides the first genome-wide characterization of the EIL family in O. fragrans, offering critical insights for molecular breeding aimed at enhancing ornamental traits and environmental resilience in this economically significant species. Full article

Flower fragrance is a crucial ornamental and economic trait of Dendrobium chrysotoxum, and the most abundant and diverse aroma-active compounds are terpenes. Terpene synthase (TPS) is the ultimate enzyme for the biosynthesis of various types of terpenes, and TPS genes were identified as the key regulators governing the spatiotemporal release of volatile terpene compounds. Until recently, the TPS gene family in D. chrysotoxum has remained largely unexplored. Our study characterizes the TPS genes in D. chrysotoxum and identifies 37 DcTPS gene family members. It helped identify the DcTPS genes, gene characteristics, the phylogeny relationship, conserved motif location, gene exon/intron structure, cis-elements in the promoter regions, protein–protein interaction (PPI) network, tissue specific expression and verification of the expression across different flowering stages and floral organs. Three highly expressed DcTPS genes were cloned, and their functions were verified using a transient expressed in tobacco leaves. Further functional verification showed that the proteins encoded by these genes were enzymes involved in monoterpene synthesis, and they were all involved in the synthesis of linalool. This study comprehensively expatiates on the TPS gene family members in D. chrysotoxum for the first time. These data will help us gain a deeper understanding of both the molecular mechanisms and the effects of the TPS genes. Furthermore, the discovery that three TPS-b genes (DcTPS 02, 10, 32) specifically drive linalool-based scent in D. chrysotoxum, will provide new insights for expanding the TPS-b subfamily in orchids and identifying the linalool synthases contributing to orchid fragrance. Full article

Current understanding of synergistic trait effects in plant–pollinator systems remains limited, particularly regarding combined visual and mechanical screening mechanisms. Given the specialized flower opening mechanisms and diverse color signals in the Papilionoideae of Fabaceae, this study examines how floral color and mechanical traits jointly mediate pollinator selection in five co-flowering sympatric species. The flower structure of Papilionoideae typically features a keel formed by fused petal lobes that encloses reproductive organs, with flower operative strength thresholds directly reflecting the mechanical resistance required to dehisce the keel and access nectar/pollen. Flower operative strength thresholds and insect mechanical capabilities were quantified, and visitation behaviors were observed under natural conditions. Significant interspecific variation in flower mechanical strength (12.59–20.25 mN) was identified, with visiting insects consistently exhibiting strengths exceeding these thresholds, suggesting mechanical barriers selectively filter pollinators. Non-visiting insects exhibited either insufficient or excessive strength relative to floral thresholds, which is related to the flower-visiting preferences of different insects. Although no linear correlation was found between flower color (RGB color space) and mechanical strength, the combined analysis revealed synergistic screening where color attracted specific pollinators from a subset capable of overcoming mechanical barriers. These findings demonstrate that flower color and mechanical traits function as complementary filters, optimizing pollinator efficiency and excluding ineffective visitors. The study highlights the necessity to explore multi-trait interactions in plant–pollinator co-evolution, with implications for biodiversity conservation and ecosystem service management. Full article

Curtobacterium species are increasingly recognized as plant pathogens and soil decomposers, but their prevalence and function as plant endophytes in aerial organs are less clear. In this study, we isolated six endophytic Curtobacterium species from the fruits, flower petals (previously unreported) and stem tissue of plants from diverse environments and examined their general characteristics. We found that all Curtobacterium endophytes belonging to three major Curtobacterium clusters—C. oceanosedimentum (a group not previously recognized as endophytic), C. luteum and C. flaccumfaciens—shared some common features. All or nearly all isolates tested were pigmented, displayed moderate salt tolerance and, surprisingly, were psychrotolerant, being able to grow at 6 °C. The exception was a fruit C. luteum isolate that appears to have evolved thermotolerance (up to 45 °C) instead as a likely adaptation to its environment. All isolates were able to metabolize starch and casein and solubilize inorganic phosphate, indicating conserved secreted hydrolase activity, but only isolates in the C. oceanosedimentum group were able to absorb and metabolize citrate. Finally, all endophytes tested were able to ferment the plant sugars sucrose and fructose, while they differed in their ability to use other sugars. Thus, this study documents common traits and adaptations in various Curtobacterium endophytes, and the presence of these isolates in floral and fruit organs implies the possible seed-borne inheritance of these isolates. Full article

The APETALA2/Ethylene-Responsive Factor (AP2/ERF) superfamily is one of the largest transcription factor families in plants, playing diverse roles in development, stress response, and metabolic regulation. Despite their ecological and economic importance, AP2/ERF genes remain uncharacterized in marigold (Tagetes erecta), a valuable ornamental and medicinal plant in the Asteraceae family known for its unique capitulum-type inflorescence with distinct ray and disc florets. Here, we conducted a comprehensive genome-wide analysis of the AP2/ERF superfamily in marigold and identified 177 AP2/ERF genes distributed across 11 of the 12 chromosomes. Phylogenetic analysis revealed their classification into the AP2 (28 genes), ERF (143 genes), RAV (4 genes), and Soloist (2 genes) families based on domain architecture. Gene structure and motif composition analyses demonstrated group-specific patterns that correlated with their evolutionary relationships. Chromosome mapping and synteny analyses revealed that segmental duplications significantly contributed to AP2/ERF superfamily gene expansion in marigold, with extensive collinearity observed between marigold and other species. Expression profiling across different tissues and developmental stages indicated distinct spatio-temporal expression patterns, with several genes exhibiting tissue-specific expression in Asteraceae-specific structures. In floral organs, TeAP2/ERF145 exhibited significantly higher expression in ray floret corollas compared to disc florets, while TeAP2/ERF103 showed stamen-specific expression in disc florets. Protein interaction network analysis revealed AP2 as a central hub with extensive predicted interactions with MADS-box and TCP family proteins. These findings suggest that AP2 family genes may collaborate with MADS-box and CYC2 genes in regulating the characteristic floral architecture of marigold, establishing a foundation for future functional studies and molecular breeding efforts to enhance ornamental and agricultural traits in this economically important plant. Full article

Globe artichoke [Cynara cardunculus var. scolymus (L.)] is a perennial composite cultivated for its immature inflorescences. Over time, the market for growers has steadily shifted away from vegetatively propagated varieties and towards seed-propagated hybrids. Since the latter tend to produce relatively late in the season, advancing the moment of flowering remains a major objective for breeders, who can benefit from insight gained into the genetic architecture of this trait. In plants, the timing of flowering is strongly regulated at the genetic level to ensure reproductive success. Genetic studies in model and non-model species have identified gene families playing crucial roles in flowering time control. One of these is the phosphatidylethanolamine-binding protein (PEBP) family, a conserved group of genes that, in plants, not only regulate the vegetative-to-reproductive phase transition, but also the development of inflorescences. In this work, we identified seven PEBP family members in the globe artichoke genome, belonging to three major clades: MOTHER OF FT AND TFL1 (MFT)-like, TERMINAL FLOWER 1 (TFL1)-like, and FLOWERING LOCUS T (FT)-like. Our results further show that CcFT expression is upregulated after the floral transition and partially complements the ft-10 mutant, whilst CcTFL1 is expressed in the shoot apex and developing inflorescences and complements the tfl1-1 mutant. These results suggest that the flowering-suppressing function of CcTFL1 is conserved in globe artichoke whereas conservation of the floral promoting function of CcFT remains uncertain. Full article