Search Results (80)

Olive, Olea europaea L. (Oleaceae), cultivation is affected by significant yield losses caused by Palpita persimilis Munroe (Lepidoptera: Crambidae), a defoliating pest in South America. Its control currently relies on synthetic pesticides, which have adverse environmental effects. This study investigated native entomopathogenic bacteria isolated from the rhizosphere of olive trees in Tacna, Peru. A total of 36 bacterial isolates were obtained, of which six strains showing more than 70% larval mortality were selected for further evaluation. Morphological and molecular analyses suggested a tentative affiliation of the isolates with bacterial groups related to the genera Lysinibacillus, Paenibacillus, Priestia, and Bacillus. Bioassays demonstrated that larval mortality depended on the bacterial concentration and exposure time. Strains such as Peribacillus sp. UNM achieved 100% larval mortality after 96 h at a concentration of 1 × 10⁹ CFU mL⁻¹. Analysis using a generalized linear model (GLM) with a binomial distribution confirmed that bacterial strain, concentration, and exposure time significantly influenced larval mortality, indicating that mortality responses varied according to bacterial concentration and exposure time. These findings provide preliminary laboratory evidence of entomopathogenic activity associated with native bacterial isolates against P. persimilis and support future investigations aimed at evaluating these isolates under field conditions in olive agroecosystems. Full article

X. fastidiosa subsp. pauca (Xfp) is the etiological agent of “Olive Quick Decline Syndrome” (OQDS). Cellina di Nardò (Olea europaea L., Oleaceae), one of the major Salento cultivars, is highly susceptible to Xfp, usually showing acute symptoms after infection. NuovOlivo^® a plant-derived formulation made with vegetal oils and water infusion from multi botanical species has been reported as effective against OQDS in plants affected by Xfp. A non-targeted ¹H NMR (Nuclear Magnetic Resonance) fingerprinting approach, with unsupervised and supervised analysis, was applied to observe the possible changes in the metabolic profile in leaf samples of cultivars Cellina di Nardò naturally affected by Xfp treated with NuovOlivo^® compared to untreated plants. The major differences were observed for the content of quinic acid, malate, mannitol, glucose, oleuropein, and aldehyde derivatives in treated compared to untreated samples. The resulting data indicated a season-dependent plant response to both disease and treatment. Moreover, the overall differences observed between the two investigated years, suggest a general decrease in the differences for the discriminating metabolites over time. The protocol NuovOlivo^® was demonstrated to promote changes in the metabolic profile of olive leaves, suggesting a possible role of this treatment, integrated with good agricultural practices, against Xfp and OQDS. Full article

The typification of five names in the genus Olea (Oleaceae), viz. O. europaea subsp. cerasiformis, O. europaea var. maderensis, O. cuspidata, O. laperrinei, and O. sylvestris is discussed. These taxa are currently classified within O. europaea at the infraspecific rank. The designation of the types is based on the consultation of original material conserved in several herbaria and the literature cited in the respective protologues. The name O. europaea subsp. cerasiformis is lectotypified from a specimen preserved at FI. The name O. europaea var. maderensis (also named O. europaea subsp. maderensis or O. maderensis, and currently treated as a synonym of O. europaea subsp. cerasiformis) is lectotypified from a specimen collected by Lowe in Madeira and preserved at BM. The name O. cuspidata (currently O. europaea subsp. cuspidata) is lectotypifed from a specimen collected in India and preserved at K. The name O. laperrinei (currently O. europaea subsp. laperrinei) is lectotypifed from a specimen preserved at MPU and collected in the Sahara Desert (Ahaggar Mountains, Algeria). Finally, the name O. sylvestris (currently O. europaea var. sylvestris), wild olive, also named oleaster or acebuche (Spanish language), a wild relative of the olive tree, is lectotypified on a Miller specimen preserved at BM. Full article

Ligustrum japonicum Thunb. (Oleaceae) has long been valued for the medicinal properties. Its fruits are traditionally utilized, while the leaves and branches are generally discarded after fruit harvest. These aerial parts therefore represent underutilized by-products whose phytochemical profiles remain insufficiently characterized. To elucidate the organ-specific chemical diversity and assess the potential value of these underutilized parts, a comparative analysis of the fruits, leaves, and branches was performed using HPLC–MS/MS combined with GNPS-based molecular networking, with a particular focus on secoiridoids, the characteristic metabolites of the Oleaceae family. This approach revealed substantial overlap as well as distinct variations in secoiridoid profiles among the three plant organs. Chromatographic separation yielded 14 secoiridoid derivatives shared across all organs. In addition, four previously undescribed secoiridoids were isolated and identified through spectroscopic analyses: secoligunosides A (1) and B (2) from the leaves and secoligunosides C (3) and D (4) from the branches. Among the major identified secoiridoids, oleuropein (10), 8Z-nüezhenide (17), and GL-3 (18) exhibited weak proliferative activity, showing an approximately 10–20% increase compared to control, on human dermal papilla cells. Collectively, these findings demonstrate that the leaves and branches not only contain key secoiridoids found in the fruits but also harbor unique metabolites, highlighting their value as alternative or complementary medicinal resources. The underutilized parts of L. japonicum therefore represent promising sources of natural products and warrant further investigation for future therapeutic applications. Full article

Background: Chionanthus retusus Lindl. et Paxt., a deciduous tree of the genus Chionanthus (Oleaceae), represents a significant native species and a widely cultivated ornamental. Its tender leaves can be processed into tea, traditionally consumed in southern China under the common name “Nuomi Cha”. Methods: Our team quantified the tea polyphenol content across 150 individual trees of C. retusus and selected three low-polyphenol (ZB_D_14, AQ_2, AQ_1) and three high-polyphenol (SX_3, SXG_D_8, TS_D_13) lines for transcriptome sequencing of their young leaves. The resulting data were analyzed to screen for candidate genes. Subsequently, transgenic plants were constructed, and their tea polyphenol content was determined. Results: A significant difference in tea polyphenol content was confirmed between the high- and low-polyphenol lines. Weighted Gene Co-expression Network Analysis (WGCNA) pinpointed a key module strongly associated with tea polyphenol synthesis, encompassing 432 DEGs, which were predominantly enriched in pathways like phenylpropanoid biosynthesis. A comparative transcriptomic analysis further yielded 84 DEGs (40 up- and 44 down-regulated). Enrichment analysis showed these were primarily involved in flavonoid and phenylpropanoid biosynthesis pathways. Expression profiling of genes in the tea polyphenol biosynthetic pathway indicated that several key genes (e.g., 4CL, CHS, DFR) were highly expressed in the high-content lines. A gene interaction network related to this synthesis identified 20 hub genes (e.g., CrHSP70-14, CrMYB44, CrbHLH92). Functional validation of four hubs (CrMYB44, CrHSP70-14, CrCDC6B, CrRAE1) via tobacco transient transformation assays demonstrated that all four significantly elevated tea polyphenol levels, with CrHSP70-14 overexpression yielding the highest content. Furthermore, stable CrHSP70-14 overexpression transgenic tobacco lines were generated, exhibiting significantly higher leaf tea polyphenol content versus controls. Conclusions: This study identifies multiple regulatory genes involved in C. retusus tea polyphenol biosynthesis, provides initial mechanistic insights, and establishes a molecular foundation for breeding specialized tea cultivars of this species. Full article

The growth and development of plants are modulated by multiple genes, among which the LBD (Lateral Organ Boundaries Domain) family—a group of plant-specific transcription factors—plays pivotal roles. In this study, we utilized the latest reference genome to identify and characterize LBD genes in Chionanthus retusus (Oleaceae, 2n = 2x = 46) and further explored their expression profiles across the different floral development, as well as their potential functions in floral morphology development. Our analysis identified a total of 76 LBD gene family members in C. retusus, which were categorized into two major families: Class I and Class II. Class I was further subdivided into five subfamilies, while Class II comprised two subfamilies. Chromosomal mapping revealed that LBD genes are distributed across all 23 chromosomes of C. retusus. Additional analyses of gene structure, conserved domains, motifs, and synteny highlighted their structural and evolutionary conservation. Subsequent expression profiling of CrLBD genes across various floral morphologies identified three members—CrLBD3, CrLBD34, and CrLBD72—that are potentially involved in regulating floral morphology in C. retusus. Full article

Osmanthus fragrans, an evergreen tree or shrub belonging to the Oleaceae family, is widely utilized in landscaping, food processing, and the fragrance industry for its unique aroma and ornamental values. Through natural and artificial selection, O. fragrans has diverged into two horticultural groups: the Asiaticus Group, which blooms year-round, and the Autumn Flowering Group, characterized by concentrated flowering in autumn. This phenotypic diversity is paramount importance for enhancing landscape value, extending the harvest periods, and meeting commercial demands. However, current research on flowering period differences among O. fragrans cultivars primarily focuses on physiological traits such as flower bud differentiation and phenological traits, with limited studies at the genetic and molecular levels. This article summarized the research progress in the classification characteristics, flower bud differentiation stages and processes, and the molecular mechanisms of flowering in O. fragrans, with a particular emphasis on the key genes that influence environmental factors such as high temperature, low temperature, and drought on the flowering period, and the regulatory mechanisms underlying the repeated flowering of the Asiaticus Group. The aim is to provide a theoretical foundation for breeding new cultivars with varied flowering times. Future research on O. fragrans will employ multi-omics technologies to systematically elucidate the key genes, signaling pathways, and epigenetic networks that regulate flower bud differentiation. A primary objective is to elucidate the synergistic interactions between environmental factors and endogenous hormones, thereby establishing precise models for flowering regulation and guiding practical production applications of O. fragrans. Full article

This investigation focuses on urban ornamental greenery, a field of research that is still relatively unexplored in Italy but is becoming increasingly important both from a botanical point of view and in relation to sustainable land management and planning. A checklist of the ornamental vascular flora of Basilicata (Southern Italy) is reported here. A total of 281 taxa were recorded, including trees, shrubs, herbaceous plants, and succulents cultivated in parks, gardens, and street trees. Such taxa (including 265 species s. str., 6 varieties, 5 subspecies, and 11 forms) belong to 201 genera, included in 94 families, among which the most represented are Rosaceae, Oleaceae, Asteraceae, Pinaceae, Cupressaceae, and Fabaceae. Phanerophytes represent the dominant growth form, and the chorological spectrum is composed mainly of Asian and American taxa. Taxa from subtropical and tropical biomes also showed a significant presence. This study highlighted the clear prevalence in the Basilicata ornamental flora of alien taxa (approximately 80%, of which 21% are naturalized aliens) compared to native ones, which is a phenomenon that is unfortunately widespread and observed worldwide. Full article

Background: Forsythia suspensa (Thunb.) Vahl is a perennial deciduous shrub of the Oleaceae family. Its dried mature fruits are used as medicine and hold an important position in traditional Chinese medicine. Tyrosine decarboxylase (TyDC) is a key enzyme involved in the synthesis of dopamine in Forsythia suspensa. At the same time, it also affects the growth and development of this species under biotic stress. Methods: This study examined the expression and function of FsTyDC1 under drought and salt stress. The TyDC gene identified in F. suspensa, termed FsTyDC1, has an open reading frame (ORF) of 1518 bp. Results: qRT-PCR and subcellular localization analyses indicated that FsTyDC1 is highly expressed in F. suspensa fruit and its protein is located in the cytoplasm. The gene was silenced using a pTRV2-FsPDS/FsTyDC1 vector with virus-induced gene silencing. Following exposure to drought and salt stress, the leaves of FsTyDC1-silenced plants exhibited increased curling and wilting. Conclusions: The results indicate that FsTyDC1 responds to both salt and drought stress, which provides a foundation for further investigation into the function of FsTyDC1. Full article

Chengiodendron marginatum, an evergreen tree or shrub belonging to the Oleaceae family, represents a critical germplasm resource with considerable potential for novel cultivar breeding. To elucidate the adaptive responses of C. marginatum to climate change and provide strategic guidance for its conservation, this study investigates the changing patterns in its potential suitable habitats under various climate scenarios. We employed an integrated approach combining maximum entropy (Maxent) modeling with GIS spatial analysis, utilizing current occurrence records and paleoclimatic data spanning from the mid-Holocene to future projections (2041–2060 [2050s] and 2061–2080 [2070s]). Climate scenarios SSP126 and SSP585 were selected to represent contrasting emission pathways. The model demonstrated excellent predictive accuracy with an AUC value of 0.942, identifying precipitation-related variables (particularly the precipitation of driest month and annual precipitation) as the primary environmental factors shaping the geographical distribution of C. marginatum. Current suitable habitats encompass approximately 98.38 × 10⁴ km², primarily located in East, Central, and South China, with high-suitability habitats restricted to southern Hainan, Taiwan, and northeastern Guangxi. Since the mid-Holocene, an expansion of suitable habitats occurred despite localized contractions in Southwest China. Future projections revealed moderate habitat reduction under both scenarios, and high-suitability areas decreased substantially. Importantly, under both scenarios, persistent high-suitability habitats were maintained in southern Hainan, Taiwan, and northeastern Guangxi, which are identified as essential climate refugia for the species. These findings provide a basis for understanding the response of the species to climate change and offer valuable guidance for its conservation. Full article

The pathogenesis of ulcerative colitis (UC) involves genetic, immunological, and environmental factors as well as gut microbiota dysbiosis. As a natural antioxidant with various pharmacological activities widely present in Oleaceae plants, oleuropein (OLE) exhibits anti-inflammatory, anti-tumor, antiviral, hypoglycemic, and cardioprotective effects. It has been validated that OLE extracted from olive oil can ameliorate UC. However, it remains unclear if and how OLE modulates the gut microbiota in the alleviation of UC. Therefore, this study was conducted to explore the mechanisms for OLE to alleviate UC induced by dextran sulfate sodium (DSS), with the focus placed on its regulatory function in the gut microbiota. The results indicated that OLE mitigated DSS-induced UC by enhancing the intestinal barrier function, reshaping the gut microbiota, and modulating bile acid metabolism. The fecal microbiota transplantation (FMT) experiment results further confirmed that the protective effect of OLE against UC could be mediated by alterations in the gut microbiota and their metabolites induced by OLE. Additionally, OLE increased the abundance of Lactobacillus and certain bile acid metabolites in the colon, including hyodeoxycholic acid (HDCA). HDCA could upregulate the expression of ZO-1 and claudin-3, restoring intestinal barrier integrity. Simultaneously, HDCA could inhibit the activation of the nuclear factor kappa-B (NF-κB) signaling pathway in the colon and relieve colonic inflammation. Overall, it was corroborated that OLE alleviated DSS-induced UC by modulating the gut microbiota and altering bile acid metabolism. Full article

Fraxinus platypoda Oliv. (Oleaceae), an ecologically and economically valuable tree species with key distribution areas in northwestern China, faces conservation challenges due to its fragmented groups and scarce individual numbers. To investigate the genetic consequences of this demographic crisis, we analyzed 65 individuals from 11 natural groups in this region using whole-genome resequencing. We identified a total of 60,503,092 single nucleotide polymorphisms (SNPs), and after further filtering, retained 3,394,299 SNPs for subsequent analysis. Population structure analysis (Neighbor-Joining tree, STRUCTURE, and kinship coefficients) revealed two distinct genetic clusters (K = 2), with principal component analysis (PCA) confirming this subdivision. Cluster I, composed of eight individuals from Groups 3, 5, 8, and 11, is highly differentiated from Cluster II and may be ancestral to it. Among the 11 groups, Groups 3 and 11 show a high genetic diversity and differentiation, with Tajima’s D > 0, indicating a long evolutionary history and balancing selection. The remaining nine groups have a low diversity, low differentiation, and frequent gene flow, with Tajima’s D < 0, suggesting directional selection. A mantel test showed no significant link between genetic variation and geographic isolation (p = 0.460). The high differentiation of Cluster I and gene flow of Cluster II are maintained by factors like evolutionary history and reproductive systems. Groups 3 and 11 are highlighted as important genetic resources deserving priority protection. This study offers key genomic data for conserving fragmented tree species and future adaptability research. Full article

Abeliophyllum distichum is a monotypic species in the family Oleaceae that contains a range of phenolic compounds and components such as coumaric acid, catechin, and verbascoside, the latter of which is a major candidate of commercial interest. In this study, we assessed the potential for producing verbascoside using callus culture. To enhance callus productivity in this regard, we evaluated the efficacy of treatment with the elicitors salicylic acid (SA) and methyl jasmonate (MeJA) based on changes in verbascoside content with callus development using Petri dish cultures. Whereas the initial content of verbascoside in A. distichum callus was approximately 50 mg/g, in response to treatment with 50 μM MeJA, we detected an increase to approximately 97.05 mg/g. In contrast, treatment with SA had no significant effects on verbascoside content. In addition, we found that the fresh weight of callus receiving elicitor treatment was lower than that of control callus. Conversely, however, in bioreactor cultures, the fresh weight of callus following treatment with 50μM MeJA for 1 week was higher than that of control callus, and the content of verbascoside in callus treated with 50 μM MeJA was higher than that in control callus. Our findings in this study thus indicate that with appropriate elicitation, the production of verbascoside by A. distichum callus pieces can be enhanced. Full article

The tree Ligustrum lucidum (W. T. Aiton, Oleaceae), native to East Asia (China), has become an aggressive invader of subtropical and temperate forests around the world. To understand how its local small-scale spread is controlled, we studied (48 plots of 4 m⁻²), in a subtropical forest of Uruguay, the distribution and survival of seedlings, saplings, and poles to assess the effects of dispersal from mother trees (distance), microsite type (forest stands defined by dominant species), and past control measures. The propagule pressure of L. lucidum, estimated through seedlings density, was between 100 and 1000 times higher than that of other species of the community and was concentrated around mother trees (<10 m of distance). Spatial variability of seedlings, saplings, and poles densities were explained by the interaction between distance to mother trees and forest stands. Significative lower densities were observed in the forest patches (stands) dominated by Jodina rhombifolia, and a field survival experiment confirmed lower survival of poles at Jodina stands, demonstrating that some resistance mechanism is operating there. We propose two biotic mechanisms of resistance: herbaceous competition and/or roots hemiparasitism by J. rhombifolia, reducing seedling and sapling survival. We concluded that a high propagule pressure, small-scale dispersal from mother trees, and patchy biotic resistance at Jodina stands control the local spread and domination process of the tree L. lucidum in the studied forest. Full article

The double-flowering phenotype is crucial for improving the ornamental value of flowering plants; this trait substantially enhances the varieties of Syringa vulgaris L. To date, no studies have examined the transcriptomics and metabolomics of key nodes in the flower bud differentiation of the single and double flowers of Syringa. This study investigated both the single and double flowers of S. vulgaris using a comprehensive, multifaceted analytical approach, including physiological assessments, transcriptomics, and metabolomics. The floral bud differentiation process can be divided into six distinct stages. Compared with the single flowers, the double flowers of S. vulgaris presented significant developmental delays during floral bud differentiation. Although there was no significant difference in the soluble protein content between the two flower types during this process, the soluble sugar content varied during pistil primordium differentiation and as temperature increased. The antioxidant enzyme activity was significantly greater in the double flowers than in the single flowers during most differentiation stages, while the malondialdehyde (MDA) level gradually increased. The levels of endogenous hormones, such as indole-3-acetic acid (IAA), gibberellin (GA₃), and abscisic acid (ABA), differed between the two flower types. The transcriptomics and metabolomics results indicated that during pistil primordium differentiation and subsequent development, the double flowers exhibited increased antioxidant enzyme activity and secondary metabolite accumulation. These secondary metabolites not only contributed to the vibrant coloration of the double flowers but also increased their cellular metabolic stability and stress tolerance through their antioxidant properties. Conversely, the rapid differentiation mechanism of the single flowers of S. vulgaris relied more on efficient primary metabolism to meet simpler structural demands. These findings not only provide scientific guidance for S. vulgaris breeding programs but also expand its potential in horticultural and landscape applications, offering a new theoretical foundation for studies on floral organ development in Oleaceae species. Full article