Search Results (197)

Skin dullness contributes to a fatigued and aged appearance, often exceeding one’s biological age. It is a common dermatological concern influenced by aging and poor lifestyle habits, regardless of ethnicity or age. This study aimed to examine advanced glycation end products (AGEs) and their receptor (receptor for AGEs [RAGE]) as contributing factors to skin dullness. AGEs themselves have a yellowish hue, contributing to “yellow dullness.” Additionally, AGE–RAGE signaling promotes melanin production in melanocytes and impairs keratinocyte differentiation as a result of inflammation. Therefore, regulating the AGE–RAGE interaction may help reduce skin dullness. Through screening various natural ingredients, we found that peony root extract (PRE) inhibits AGE formation and blocks AGE–RAGE binding. Furthermore, the presence of PRE leads to the suppression of AGE-induced melanin production in melanocytes and the restoration of impaired keratinocyte differentiation in glycated basement membrane components. In a human clinical study, topical application of a 1% PRE-containing lotion for 2 weeks significantly reduced melanin content, with a trend toward decreased AGE accumulation and visible spots on the cheeks. These findings support the potential of PRE as a multifunctional cosmetic ingredient that comprehensively addresses skin dullness by modulating the AGE–RAGE interaction. Full article

Background/Objectives: Paeonia delavayi, a high-altitude-adapted medicinal and oil-producing plant, exhibits broad elevational distribution. Understanding how environmental factors regulate its growth across altitudes is critical for optimizing cultivation and exploiting its economic potential. Methods: In this study, we conducted a comprehensive Iso-Seq and RNA-seq analysis to elucidate the transcriptional profile across diverse altitudes and three seed developmental stages. Results: Using Pacbio full-length cDNA sequencing, we identified 39,267 full-length transcripts, with 80.03% (31,426) achieving successful annotation. RNA-seq analysis uncovered 11,423 and 9565 differentially expressed genes (DEGs) in response to different altitude and developmental stages, respectively. KEGG analysis indicated that pathways linked to fatty acid metabolism were notably enriched during developmental stages. In contrast, pathways associated with amino acid and protein metabolism were significantly enriched under different altitudes. Furthermore, we identified 34 DEGs related to fatty acid biosynthesis, including genes encoding pivotal enzymes like biotin carboxylase, carboxyl transferase subunit alpha, malonyl-CoA-acyl carrier protein transacylase, 3-oxoacyl-ACP reductase, 3-hydroxyacyl-ACP dehydratase, and stearoyl-ACP desaturase enoyl-ACP reductase. Additionally, ten DEGs were pinpointed as potentially involved in high-altitude stress response. Conclusions: These findings provide insights into the molecular mechanisms of fatty acid biosynthesis and adaptation to high-altitude stress in peony seeds, providing a theoretical foundation for future breeding programs aimed at enhancing seed quality. Full article

Background: The peony (Paeonia suffruticosa Andr.), a globally valued woody ornamental species, suffers severe heat-induced floral damage that compromises its horticultural value. While the HSP20 proteins are critical for plant thermotolerance, their genomic organization and regulatory dynamics remain uncharacterized in the peony. This study aims to systematically identify the PsHSP20 genes, resolve their molecular features, and elucidate their heat-responsive expression patterns to enable targeted thermotolerance breeding. Methods: The genome-wide identification employed HMMER and BLASTP searches against the peony genome. The physicochemical properties and protein structures of the gene family were analyzed using online websites, such as Expasy, Plant-mPLoc, and SOPMA. The cis-regulatory elements were predicted using PlantCARE. Expression profiles under different times of 40 °C heat stress were validated by qRT-PCR (p < 0.05). Results: We identified 58 PsHSP20 genes, classified into 11 subfamilies. All members retain the conserved α-crystallin domain, and exhibit predominant nuclear/cytoplasmic localization. Chromosomal mapping revealed uneven distribution without lineage-specific duplications. The promoters were enriched in stress-responsive elements (e.g., HSE, ABRE) and in 24 TF families. The protein networks linked 13 PsHSP20s to co-expressed partners in heat response (GO:0009408) and ER protein processing (KEGG:04141). Transcriptomics demonstrated rapid upregulation of 48 PsHSP20s within 2 h of heat exposure, with PsHSP20-12, -34, and -51 showing the highest induction (>15-fold) at 6 h/24 h. Conclusions: This first genome-wide study resolves the architecture and heat-responsive dynamics of the PsHSP20 family. The discovery of early-induced genes (PsHSP20-12/-34/-51) provides candidates for thermotolerance enhancement. These findings establish a foundation for molecular breeding in the peony. Full article

Plant-specific WUSCHEL (WUS)-related homeobox (WOX) family of transcription factors are involved in apical meristem maintenance, embryogenesis, lateral organ development, and hormone signaling. Among the members of this family, WOX1 is known to play essential roles in many species. However, the function of the peony ‘Feng Dan’ (Paeonia ostii L.) WOX1 (PoWOX1) remains unknown. The initial bioinformatic analysis revealed that PoWOX1 belongs to the modern clade of the WOX gene family and has a highly conserved homeodomain (HD), the WUS motif, the STF-box, and the MAEWEST/WOX4-box. Subsequent heterologous overexpression in Arabidopsis thaliana revealed that PoWOX1 promotes root growth, early shoot initiation, and flowering. The root vascular tissues, especially the arrangement and size of xylem cells, were different between the PoWOX1-overexpressing transgenics and the wild-type plants, and the pericycle cells adjacent to the xylem divided more easily in the transgenics than in the wild type. Furthermore, under in vitro conditions, the transgenic leaf explants exhibited more callus induction and differentiation than the wild-type leaf explants. Thus, the study’s findings provide novel insights into the role of PoWOX1 in promoting root development and callus tissue induction and differentiation, serving as a reference for developing an efficient regeneration system for the peony. Full article

Tree peony is well-known for its ornamental value, medicine function, oil, and edible use. However, the difficulty in propagating tree peony impedes its cultivation and industrial advancement. Softwood cutting is an effective method to promote the propagation of tree peony. This research investigated the effects of several factors (cultivar, cutting phenological stage, auxin type, polyamine, and substrate) on the rooting of softwood cutting in tree peony. The results showed that rooting ability varied with cultivars and cutting phenological stages, with the highest rooting rates being for ‘High noon’ and ‘Jinghua Qingxue’ during the vigorous growth stage, reaching 50% and 53.33%, respectively. IBA 2000 mg·L⁻¹ was optimal for rooting in ‘High noon’ cuttings, with the maximum root number (5.67) and root length (6.3 cm). Putrescine of 1.0 mM could significantly improve the rooting rate and rooting quality of ‘Jinghua Qingxue’ cuttings, which had the highest rooting rate of 54.17% in the cocopeat/perlite substrate (v:v 1:1). Anatomical observation showed that most adventitious roots were generated from callus meristem nodules differentiated from cortical parenchyma cells while a few came from stem bark, as well as integrated root induction. This study is an innovation in and supplement to tree peony propagation research, and a propagation protocol was primarily established for softwood cuttings in tree peony. Full article

Peonies (Paeonia spp.) are renowned for their beautiful ornamental flowers and significant cultural, medicinal, and economic values. Based on growth habit, peonies are categorized into herbaceous and tree peonies. Viral infections in peonies, historically referred to as “peony ringspot” or “peony mosaic” diseases, have been reported worldwide over decades. Infections symptoms typically include leaf discoloration and diminished flowering, substantially reducing both ornamental and commercial quality. In severe cases, viral diseases can cause stunted plant growth and impaired flowering, directly affecting peony cultivation and the floriculture profitability. This review systematically summarizes the current research on key viral diseases in peonies, addressing disease classification, symptomatology, causative viruses, pathogenesis, molecular virus–host interactions, and contemporary approaches for prevention and management. The insights provided in this review offer a theoretical foundation and practical guidelines to facilitate effective control of peony viral diseases, potentially promoting sustainable development within the peony industry. Full article

The tree peony holds significant historical, cultural, and practical value. P. ostii is extensively cultivated in China, where it represents the primary oil-producing variety of tree peonies. However, the current nutrient supplementation system for P. ostii lacks an empirical basis, resulting in frequent wastage of nutrients during daily production. In this study, varying ratios and quantities of nitrogen, phosphorus, and potassium were administered to P. ostii at distinct phases of its annual growth cycle, specifically during the bud sprouting, post-flowering, and dormancy periods. The results showed that during the bud sprouting period, the plants treated with a high nitrogen and potassium ratio (a high N&K ratio, N–P–K = 35%–20%–35%) had better flowering traits than those treated with a high phosphorus ratio (a high P ratio, N–P–K = 20%–35%–20%). Under the standard application amount, plants treated with a high N&K ratio outperformed those treated with a high P ratio in terms of flowering duration, net photosynthetic rate, and flowering biomass, with increases of 20.9%, 10.7%, and 32.9%, respectively. During the post-flowering period, all plants died when treated with 1.5 × standard amounts of the above ratios. At this period, the all-high ratio with N–P–K = 45%–45%–45% resulted in a 70.4% increase in fruit set, a 43.8% increase in seed number, and a 153.8% increase in biomass compared with the high N&K ratio. During the dormancy period, nutrient supplementation with the standard amount of P led to higher increases in ground diameter and biomass. Therefore, in subsequent tree peony production, particular attention should be paid to nutrient supplementation during the post-flowering period to prevent excessive fertilizer application and safeguard the plants’ normal growth and development. Full article

Peonies are globally renowned ornamental plants, and distant hybridization is a key method for breeding new varieties, though it often faces cross-incompatibility challenges. The metabolic mechanisms underlying the crossing barrier between tree peony (Paeonia sect. Moutan) and herbaceous peony (P. lactiflora) remain unclear. To identify key metabolites involved in cross-incompatibility, we performed a cross between P. ostii ‘Fengdanbai’ (female parent) and P. lactiflora ‘Red Sara’ (male parent) and analyzed metabolites in the stigma 12 h after pollination using UPLC-MS. We identified 1242 differential metabolites, with 433 up-regulated and 809 down-regulated, including sugars, nucleotides, amino acids, lipids, organic acids, benzenoids, flavonoids, and alkaloids. Most differential metabolites were down-regulated in hybrid stigmas, potentially affecting pollen germination and pollen tube growth. Cross-pollinated stigma exhibited lower levels of high-energy nutrients (such as amino acids, nucleotides, and tricarboxylic acid cycle metabolites) compared to self-pollinated stigma, which suggests that energy deficiency is a contributing factor to the crossing barrier. Additionally, cross-pollination significantly impacted KEGG pathways such as nucleotide metabolism, purine metabolism, and vitamin B6 metabolism, with most metabolites in these pathways being down-regulated. These findings provide new insights into the metabolic basis of cross-incompatibility between tree and herbaceous peonies, offering a foundation for overcoming hybridization barriers in peony breeding. Full article

Flavonoid biosynthesis is proposed to play a critical role in floral organ development in Paeonia species. However, its specific involvement in stamen petalization remains unclear. This study identified and characterized 13 gene families related to flavonoid biosynthesis across four Paeonia species. Comparative and phylogenetic analysis revealed that most flavonoid biosynthesis-related genes experience lineage-specific expansion in P. ludlowii. Genes belonging to the same family were commonly clustered on chromosomes and displayed highly conserved domain and motif compositions. The cis-element analysis identified Cis-acting elements associated with light, hormonal, and stress responses, implicating their regulatory roles in flavonoid biosynthesis. To further investigate the role of these genes in stamen petalization of P. lactiflora, expression profiling analyses were performed on ‘Fen Yu Nu’ (normal stamens) and ‘Lian Tai’ (petaloid stamens) cultivars using transcriptomic data released previously. Three quercetin-related genes revealed distinct stage-specific patterns in ‘Fen Yu Nu’ and ‘Lian Tai’. Notably, PlaF3’H03 exhibited significant upregulation during petaloid stamen development in ‘Lian Tai’, suggesting its role in stamen transformation. Molecular docking identified PlaF3’H07 as a key enzyme with strong substrate-binding affinity (ΔG = −4.7 kcal/mol), supporting its catalytic function in quercetin synthesis. The expression pattern of key flavonoid biosynthetic genes was also confirmed across three developmental stages of floral buds by real-time quantitative PCR. This study provides insights into the genetic basis underlying stamen petalization in P. lactiflora and offers potential targets for genetic improvement of floral traits in Paeonia and other ornamental plants. Full article

In this study, we added peony seed oil (PSO) to wheat dough and made corresponding steamed breads. Through the dynamic rheological tests of the dough, microstructure analyses, bread quality evaluations, crystallization characteristic experiments, and texture characteristic measurements, we revealed the influence mechanisms of the different contents of PSO on the quality characteristics of the wheat dough and Chinese steamed breads. The results showed that adding PSO at 2% (wheat flour weight basis) had a positive effect on the dough’s viscoelasticity, while the G′ and G″ of doughs with higher contents were decreased. When PSO was added in the range from 2.0% to 4.0% (wheat flour weight basis), the scanning electron microscope observation results showed that the reticular structure of dough was denser. The specific volume of the resulting steamed breads increased, the breads were softer, and their chewability was better. The crystallinity of the steamed bread with added PSO was lower, and the hardness of the steamed bread after 24 h of storage was significantly lower than that of the control group, which proved that PSO could delay the staling of steamed breads. This study provides a new idea for the application of PSO as a dietary supplement. Full article

Paeonia ludlowii is a threatened and valuable germplasm in the cultivated tree peony gene pool, with distinctive traits such as tall stature, pure yellow flowers, and scarlet foliage in autumn. However, the crossability barrier limits gene transfer from P. ludlowii to cultivated tree peony. Therefore, our study investigated the reasons for the lack of crossability between P. ludlowii and Paeonia ostii ‘Fengdan’. Distant cross pollination (DH) resulted in the formation of many calloses at the ends of the pollen tubes, which grew non-polar, twisted, entangled, and often stopped in the style. Pollen tubes elongated the fastest in self-pollination (CK), and pollen tubes elongated faster and fewer pollen tube abnormalities were observed in stigmas treated with KCl solution before pollination (KH) than in DH. During pollen–pistil interactions, the absence of stigma exudates, high levels of H₂O₂, O₂⁻, MDA, ^•OH, ABA, and MeJA, and lower levels of BR and GA₃ may negatively affect pollen germination and pollen tube elongation in the pistil of P. ostii ‘Fengdan’. Pollen tubes in CK and KH penetrated the ovule into the embryo sac at 24 h after pollination, whereas only a few pollen tubes in DH penetrated the ovule at 36 h after pollination. Pre-embryo abnormalities and the inhibition of free nuclear endosperm division resulted in embryo abortion in most of the fruits of DH and many fruits of KH, which occurred between 10 and 20 days after pollination, whereas embryos in CK developed well. Early embryo abortion and endosperm abortion in most of the fruits of DH and KH led to seed abortion. Seed abortion in KH and DH was mainly due to an insufficient supply of auxins and gibberellins and lower content of soluble protein and soluble sugars. The cross failure between P. ludlowii and P. ostii ‘Fengdan’ is mostly caused by a pre-fertilization barrier. KH treatment can effectively promote pollen tube growth and facilitate normal development of hybrid embryos. These findings provide new insights into overcoming the interspecific hybridization barrier between cultivated tree peony varieties and wild species. Full article

The spraying time of nitrogen fertilizer is a key factor to consider when fertilizing with an intelligent micro-sprinkler irrigation system. This study aims to investigate the impact of nitrogen fertilizer spraying time on the seed oil quality of tree peony, with the expectation of providing theoretical support for the application of intelligent micro-sprinkler irrigation systems in the production of tree peony. In 2022 and 2023, foliar nitrogen application was conducted on Paeonia ostii ‘Fengdan’ utilizing an intelligent micro-spray irrigation system, with four distinct nitrogen fertilizer spraying times (3:00–4:00, 7:00–8:00, 14:00–15:00, and 19:00–20:00). Based on this, the study assessed nitrogen metabolism indicators in leaves and seeds at various growth stages and the fatty acid composition of seed oil in Paeonia ostii ‘Fengdan’. The results revealed that foliar nitrogen application between 14:00 and 15:00 significantly enhanced the levels of free amino acids (FAA), nitrate reductase (NR), glutamine synthetase (GS), and glutamate synthase (GOGAT) activity in both leaves and seeds. Furthermore, the ratio of α-linolenic acid in the seed oil was significantly increased. Correlation analysis demonstrated a positive or highly significant positive correlation between the levels of nitrogen metabolism indicators and the ratio of unsaturated fatty acids. In conclusion, foliar nitrogen application between 14:00 and 15:00 significantly enhances the FAA content and the activity of nitrogen metabolism enzymes within the leaves and seeds and promotes the synthesis of unsaturated fatty acids in seed oil. This study contributes to the efficient and high-quality cultivation of tree peony. Full article

Gibberellin (GA₃) plays a crucial role in regulating the flowering time of tree peony (Paeonia suffruticosa Andr.). However, its function on flower opening after dormancy release remains unclear, and its molecular mechanism need further study. We investigated the effects of exogenous GA₃ treatments at 800 mg/L, 900 mg/L, and 1000 mg/L on the flowering process of five-year-old peony plants (‘Luhehong’) under greenhouse conditions. Our results showed that exogenous GA₃ significantly accelerated the flower opening process. Specifically, flower buds treated with 800 mg/L and 900 mg/L GA₃ bloomed after 42 and 45 days, respectively. In contrast, all flower buds treated with 1000 mg/L GA₃ aborted, while only one flower bud in the control group bloomed after 56 days. Furthermore, analysis of endogenous hormone levels revealed that GA₃ treatment rapidly increased endogenous GA₃ levels, decreased ABA levels, and gradually increased IAA levels. Transcriptomic analysis of flower buds released from dormancy following GA₃ treatment identified multiple key genes involved in the flower opening process of peony. Notably, members of the C2H2, C3H, ERF, bHLH, MYB, bZIP, NAC, and WRKY families showed significant differential expression. Moreover, several key genes involved in GA₃, ABA, and IAA hormone signaling pathways were also differentially expressed. Our findings suggested that an appropriate concentration of exogenous GA₃ treatment could accelerate the flower opening process in tree peony through multiple pathways, which would provide valuable insights into the molecular mechanisms underlying the gibberellin-mediated flower opening process in tree peony. Full article

In Europe, Paeonia officinalis and P. peregrina, along with Chinese P. lactiflora, are commonly used for medicinal purposes. This comprehensive review summarizes the secondary metabolites and biological activities of P. peregrina, P. officinalis, P. tenuifolia, P. mascula, P. lactiflora, and the ornamental cultivars derived from the last taxon. Terpenoids, flavonoids, and phenolic acids are present in all five species, while tannins, lipids, and organic acids have been identified in only some. All five species exhibit antioxidant and antimicrobial potential, alongside anti-inflammatory, anticancer, neuroprotective, antisclerotic, antidiabetic, and various other bioactivities. The data were accessed via Scopus, Web of Science, PubMed, and Google Scholar search engines. The review also reveals that P. officinalis and P. lactiflora have been far more extensively studied than P. peregrina, P. tenuifolia, and P. mascula in terms of their chemical composition and pharmacological properties. The genus Paeonia L. comprises 37 accepted species, many of which are renowned for their ornamental and medicinal value. Native to Bulgaria are P. peregrina, P. tenuifolia, and P. mascula, with the latter two being protected by the Bulgarian Biodiversity Act. The collection of substances from all three species is subject to regulatory restrictions. This review reveals the possible use of P. lactiflora as a substitute for P. peregrina. Full article

Peony mead, an emerging fermented beverage, has attracted attention because of its unique flavor and health benefits. The dynamic changes in sensory quality and the molecular mechanisms involved during post-fermentation are still unclear, limiting its industrial production. In this study, GC-IMS (gas chromatography-ion mobility spectrometry) and UHPLC-MS/MS (ultrahigh-performance liquid chromatography–tandem mass spectrometry) were employed to systematically analyze the variations in aroma and quality of peony mead across aging stages. During the aging process, titratable acid content increased significantly, while soluble solids and reducing sugars decreased. Total phenol content initially rose but subsequently declined. Sensory analysis demonstrated that the sweet–acid balance and polyphenol content were critical in shaping the sensory characteristics of the product. Seventeen key volatile metabolites were identified via GC-IMS, with the 2-methyl-1-propanol dimer/polymer and 3-methyl-1-butanol dimer/polymer serving as potential characteristic markers. These key volatile metabolites underwent physicochemical reactions, yielding complex and coordinated aroma characteristics. UHPLC–MS/MS analysis revealed that nonvolatile metabolites changed significantly, which were driven by nonenzymatic reactions such as redox reactions, hydrolysis, and condensation. In addition, correlation analysis identified mechanisms by which key metabolites potentially contributed to sensory properties such as floral aroma, fruit fragrance, sweetness, sourness, etc. This study provided insights into quality changes during aging and supported the development of high-quality fermented beverages. Full article