Exploring the Effect of Active Components in Oil Tree Peony Seed Meal on Swine Disease Resistance and its Potential Mechanisms Based on Network Pharmacology and Molecular Docking.

This study aims to explore the feasibility of using network pharmacology and molecular docking technology to predict the effects of active components from oil tree peony seed meal (PSM) on swine diseases. Ten active components of PSM were screened Screening through literature search and network pharmacology standards, including Betulinic acid, Quercetin, Kaempferol, Luteolin, Isorhamnetin, Hydroxygenkwanin, Hederagenin, Benzoyl Paeoniflorin, Albiflorin, Paeoniflorin. Ten types of swine diseases were selected, including African Swine Fever, Aftosa, Swine Vesicular Disease, Transmissible Gastroenteritis, Swine Streptococcal Infection, Blue Aural Disease, Swine Infectious Atrophic Rhinitis, Swine Influenza, Swine Erysipelas, Swine Epidemic Encephalitis. The results showed that the average number of cross genes between the potential target genes of PSM active components and each swine disease target gene accounted for 7.64 % of the total number of swine disease target genes. The GO enrichment analyses showed that putative targets exist in endosomes, lysosomes, cell membranes, nerves, growth factor activity, receptor tyrosine kinase binding, enzyme binding, growth factor binding, transcription coactivator binding, oxidoreductase activity, prostaglandin E receptor activity and insulin receptor substrate binding. The KEGG enrichment analysis results showed that these putative genes were involved in various cancer progression pathways, signaling pathways, and hormone regulatory pathways. A total of 8 core targets were obtained through protein-protein interaction networks analysis, including Protein Kinase CAMP-Activated Catalytic Subunit Alpha (PRKACA), Non-Receptor Tyrosine Kinase (SRC), Mitogen-Activated Protein Kinase 1 (MAPK1), E1A Binding Protein P300 (EP300), Hypoxia Inducible Factor 1 Subunit Alpha (HIF1A), Phosphatidylinositol-4,5-Bisphosphate 3-Kinase Catalytic Subunit Beta (PIK3CB), C-X-C chemokine receptor type 4 (CXCR4) and Estrogen Receptor 2 (ESR2). The HIF-1 signaling pathway was found to be associated with all 10 selected swine diseases. The PD-L1 expression, and PD-1 checkpoint pathway in cancer, and thyroid hormone signaling pathway were not only enriches the core target with a quantity of 7, but also associated with 9 Swine diseases. In addition, the molecular docking results indicate that the core ingredients have strong affinity with hub genes. The research suggests that the active components of PSM may intervene in swine diseases through multiple components, targets, and pathways.

First report of leaf spot on Gleditsia sinensis caused by Colletotrichum gloeosporioides in China.

Gleditsia sinensis Lam (Lamarck et al., 1788) is an endemic species widely distributed in China. In Sep. 2022, leaf spot symptoms were observed on G. sinensis in Xuhui district (31◦9'16''N, 121◦26'36''E), Shanghai, China, with an incidence rate of 55% in the examination of 9 trees. The leaves showed typical symptoms of anthracnose with irregular gray-brown spots and sunken areas. For isolation, 5 × 5 mm sections were cut from the lesion edge of 20 infected leaves collected from 2 trees. The surface of the sections was sterilized by immersion in 75% ethanol for 30 s, followed by 5% NaClO for 1 min, rinsed three times with sterile water, and dried on sterile filter paper. These sections were placed on PDA plates incubated at 25°C in darkness. Eighteen isolates with similar colony morphology were obtained and purified by single spore culturing. Two isolates (YKY2301, 2302) from separate trees were further tested. On the 6th day, the colonies had a diameter of 7.6 to 8.4 cm and appeared white to gray-white with aerial hyphae. The colony's central part exhibited an orange hue due to the conidia accumulation, while the undersides displayed an orange-yellow color. The hyphae were hyaline and smooth, with septa and branches, and the conidia were cylindrical with blunt to slightly rounded ends, measuring 13.1 to 18.8 (average 15.9) µm× 4.0 to 6.6 (average 5.4) µm (n=184). From conidia germinated on glass slides, the appressoria measured 5.5 to 6.3 µm ×4.9 to 5.1 µm (n=50) and were nearly spherical or elliptical in shape. These characteristics matched those of the Colletotrichum gloeosporioides species complex (Cannon et al., 2012; Weir et al., 2012). For molecular identification, the genomic DNA was extracted using a modified CTAB method (Luo et al., 2012). Gene fragments including ITS (PP125667, PP125668), GAPDH (PP153428, PP153429), ACT (PP153424, PP153425), TUB2(PP153917, PP190256), and ApMAT (PP153426, PP153427) were obtained by PCR using universal primers (Huang et al., 2022) and sequenced. The sequences exhibited 98.19% to 99.82% identity with the corresponding gene of the type strain C. gloeosporioides IMI356878 (JX010152, JX010056, JX009531, JX010445, JQ807843) in NCBI BLAST. A multilocus Maximum likelihood phylogenetic tree was constructed based on concatenated the five genes by PhyloSuite. It showed that YKY2301, 2302 were on the same branch with C. gloeosporioides. Based on these results, the isolates were identified as C. gloeosporioides. Pathogenicity tests were conducted by mycelial and conidia inoculation. 5 mm mycelial or blank agar plugs were inoculated onto the leaves of 2 healthy trees in a garden (25 to 30 °C), with and without wounds made by toothpick pricking (n≥3 per group). All mycelial inoculated leaves showed leaf spots on the 6th day. Three healthy 2-year-old seedlings were inoculated with either conidia (108 conidia/ml) or water by leaf spray, and maintained in a climate chamber (27 °C, 80% humidity). Inoculated seedlings showed necrotic leaf spots on day 14, and wilted within 3 weeks. The controls in all tests remained asymptomatic. The pathogen has been re-isolated and confirmed by sequencing, thus fulfilling Koch's postulates. This is the first report of leaf spots caused by C. gloeosporioides on G. sinensis in the world. As illustrated by the example of legume pod infection (Gerusa et al., 2019), it poses a potential threat to the fruits of G. sinensis, despite currently only affecting their ornamental value. This report provides basic information for future research.

Inhibitory Activities of Five Fungicides on Alternaria suffruticosae and Their Field Control Efficacy Against Tree Peony Black Spot.

Tree peony black spot (TPBS), mainly caused by Alternaria suffruticosae, is a common leaf disease on the ornamental peony, which poses a great threat to the flower buds in the current year and the flowering quality in the next year. However, there is only one fungicide registered for the control of this disease, difenoconazole. In order to avoid the severe problem of pathogen resistance caused by long-term use of difenoconazole, it is necessary to screen more chemical fungicides for the prevention and control of TPBS. In this study, the biological activities of flutolanil, phenamacril, pyraclostrobin, and boscalid on mycelial growth, conidial germination, germ tube elongation, and sporulation quantity of A. suffruticosae were determined, and the field control efficacy was tested to evaluate the preventive and therapeutic activities. Difenoconazole was used as a control simultaneously. The results showed that pyraclostrobin had the strongest inhibitory effects on the conidial germination, mycelium growth, germ tube elongation, and sporulation quantity, with the average EC50 values of 0.0517, 0.5343, 0.0008, and 0.8068 µg/ml, respectively. The inhibitory activity of flutolanil on the four developmental stages of A. suffruticosae was weaker than that of the other three fungicides. Compared with flutolanil, boscalid, the other succinate dehydrogenase inhibitor, had more strong inhibitory effects on the mycelial growth and sporulation quantity, with the average EC50 values of 3.8603 and 1.4760 µg/ml, respectively. Phenamacril had a moderate inhibitory level and had more inhibitory activity on conidial germination and germ tube elongation, with the average EC50 values of 31.5349 and 5.2597 µg/ml, respectively. All of the four fungicides had no significant effects on the shape of spores and germ tubes. The control fungicide difenoconazole had the strongest inhibitory activity on mycelial growth, and the average EC50 value was only 0.3297 µg/ml. However, its inhibitory activity on the other three growth stages was not high. In the field trials, pyraclostrobin had high control efficacy on TPBS even at low concentrations, reaching a minimum of 62.6293%, which was higher than that of difenoconazole. The other three fungicides had higher control efficacy at high concentrations but decreased significantly at low concentrations. Considering the dosage and control efficacy, pyraclostrobin was the first choice for the control of TPBS. Pyraclostrobin is the preferred alternative fungicide to difenoconazole for the prevention and control of TPBS in production.

Molecular mechanism of somatic embryogenesis in paeonia ostii 'Fengdan' based on transcriptome analysis combined histomorphological observation and metabolite determination.

BACKGROUND: Tree peony (Paeonia sect. Moutan DC.) is a famous flower native to China with high ornamental, medicinal, and oil value. However, the low regeneration rate of callus is one of the main constraints for the establishment of a genetic transformation system in tree peony. By histomorphological observation, transcriptomic analysis and metabolite determination, we investigated the molecular mechanism of somatic embryogenesis after the establishment of a culture system and the induction of somatic embryo(SE) formation. RESULTS: We found that SE formation was successfully induced when cotyledons were used as explants. A total of 3185 differentially expressed genes were screened by comparative transcriptomic analysis of embryogenic callus (EC), SE, and non-embryogenic callus (NEC). Compared to NEC, the auxin synthesis-related genes GH3.6 and PCO2 were up-regulated, whereas cytokinin dehydrogenase (CKX6) and CYP450 family genes were down-regulated in somatic embryogenesis. In SE, the auxin content was significantly higher than the cytokinin content. The methyltransferase-related gene S-adenosylmethionine synthase (SAMS) and the flavonoid biosynthesis-related gene (ANS and F3'5'H) were down-regulated in somatic embryogenesis. The determination of flavonoids showed that rhoifolin and hyperoside had the highest content in SE. The results of transcriptome analysis were consistent with the relative expression of 8 candidate genes by quantitative polymerase chain reaction analysis. CONCLUSION: The results revealed that auxin and cytokinin may play a key role in 'Fengdan' somatic embryogenesis. The genes related to somatic embryogenesis were revealed, which has partly elucidated the molecular mechanism of somatic embryogenesis in 'Fengdan'.

Reference genes selection of Paeonia ostii 'Fengdan' under osmotic stresses and hormone treatments by RT-qPCR.

BACKGROUND: Tree peony possess significant ornamental, medicinal and oil values. Osmotic stresses including dehydratiuon and salinity limit the expansion of cultivation area of tree peony. Information on reference genes selection under osmotic stress and hormone stimulation of tree peony still limited. This study aimed to determine the stable reference genes suitable for tree peony under osmotic stresses and hormone treatments, and provide a theoretical basis for the molecular biology research. METHODS AND RESULTS: Twelve candidate reference genes were evaluated in Paeonia ostii 'Fengdan' under osmotic stress and hormone treatments by RT-qPCR. Delta Ct method, geNorm, and NormFinder were used for the comprehensive expression stability ranking comparison. The results revealed that tubulin-α was the preferred internal reference genes for drought and ABA treatment, tubulin-ß was identified as the most suitable reference gene under drought and OPDA induction, 18s-rRNA was regarded as the most stable gene for salinity and JA treatment, eIF-5 A was listed as the most stable gene for JA and MeJA treatments. The experiments also displayed that EF1-α were comparatively unstable under ABA and BR hormone treatments. CONCLUSION: These preferred reference genes could be useful in qPCR studies involving osmotic or hormonal stresses in Paeonia ostii 'Fengdan'. It is anticipated that the results will benefit tree peony functional genomics studies and molecular breeding research in the future.

Ascription of nosZ gene, pH and copper for mitigating N2O emissions in acidic soils.

Soil nitrous oxide (N2O) emissions are alarming for global warming and climate change. N2O reduction is carried out only by nosZ gene encoded N2O-reductase, which is highly sensitive to acidic pH and copper (Cu) contents. Therefore, a microcosm study was conducted to examine the attribution of soil pH management, Cu supply and nosZ gene abundance for N2O emission mitigation. Cu was applied at the dose of 0, 10, 25 and 50 mg kg-1 to three acidic soils (Soil 1, 2 and 3) without and with dolomite (0 and 5 g kg-1). Cu application and soil pH increment substantially enlarged the abundance of nosZ gene, and consequently mitigated soil N2O emissions; highest reduction with 25 Cu mg kg-1. Decline in NH4+ and subsequently accumulation of NO3-, and large contents of MBC and DOC in dolomite treated soils led to a substantial N2O reduction. The cumulative N2O emissions were lowest in the treatment of 25 Cu mg kg-1 with dolomite application for each soil. Results suggest that soil pH increment, an adequate Cu supply, and nosZ gene abundance can potentially lower soil N2O emissions in acidic soils.

Paeoniflorin combined with norfloxacin ameliorates drug-resistant Streptococcus suis infection.

BACKGROUND: The increased resistance of bacterial pathogens to fluoroquinolones (FQs), such as norfloxacin and ciprofloxacin, supports the need to develop new antibacterial drugs and combination therapies using conventional antibiotics. The LuxS/AI-2 quorum sensing (QS) system can regulate the complex group behaviour of Streptococcus suis and impact its susceptibility to FQs. OBJECTIVES: We investigated the combination of paeoniflorin and norfloxacin as a novel and effective strategy against FQ-resistant S. suis. METHODS: FIC, AI-2 activity assay, real-time RT-PCR and biofilm inhibition assays were performed to investigate the in vitro effect of paeoniflorin combined with norfloxacin. Mouse protection and mouse anti-infection assays were performed to investigate the in vivo effect of paeoniflorin combined with norfloxacin. RESULTS: FIC results showed that paeoniflorin and norfloxacin exert a synergistic bactericidal effect. Evidence was brought that paeoniflorin reduces the S. suis AI-2 activity and significantly down-regulates the transcription of the FQ efflux pump gene. In addition, paeoniflorin can inhibit biofilm formation, thereby promoting the ability of norfloxacin to kill S. suis. Finally, we showed in a mouse model that paeoniflorin in association with norfloxacin is effective to treat S. suis infections. CONCLUSIONS: This study highlighted the inhibitory potential of paeoniflorin on the LuxS/AI-2 QS system of S. suis, and provided evidence that it can inhibit the FQ efflux pump and prevent biofilm formation to cooperate with norfloxacin in the treatment of resistant S. suis-related infections.

Characteristics of PoVIN3, a Key Gene of Vernalization Pathway, Affects Flowering Time.

The tree peony (Paeonia section Moutan DC.) is the candidate flower in China, with abundant germplasm resources and high ornamental value. However, the short and concentrated flowering period severely restricted the improvement of the economic value of tree peonies. Based on the full-length transcriptome database of tree peonies, the PoVIN3 (GenBank ID: OP341879), involved in the flowering regulation of tree peonies were identified and cloned for the first time. The PoVIN3 was also characterized by bioinformatics methods, quantitative real-time PCR (qRT-PCR), and the establishment of a transgenic system. The expression levels of PoVIN3 in seven different petals developmental stages were the highest at the initial flowering stage of the variant cultivar of Paeonia ostii 'Fengdan,' the initial decay stage of the normal flowering Paeonia ostii 'Fengdan,' and the half opening stage of the late flowering Paeonia suffruticosa 'Lianhe.' Tissue-specific expression analysis showed that the relative expression levels of PoVIN3 were the highest in sepals of both normal flowering Paeonia ostii 'Fengdan' and the late flowering Paeonia suffruticosa 'Lianhe,' and the highest expression was in stamens of early flowering mutant Paeonia ostii 'Fengdan.' In addition, the flowering time of pCAMBIA2300-PoVIN3 transgenic plants was significantly earlier than that of the wild-type, indicating that PoVIN3 could promote plant flowering. The results provide a theoretical basis for exploring the role of PoVIN3 in the regulation of flowering in tree peonies.

Molecular characterization and expression analysis of the SQUAMOSA PROMOTER BINDING PROTEIN-LIKE gene family in Paeonia suffruticosa.

KEY MESSAGE: A total of 16 PsSPL genes were identified in tree peony. PsSPLs potentially regulated flowering time, lateral bud and seed development, and the juvenile-to-adult phase transition. SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL) transcription factors are important for plant growth and development. Here, we report the identification of 16 full-length PsSPLs in tree peony (Peaonia suffruticosa Andr.) and 9 PsSPLs that have miR156 target sites. Phylogenetic analysis of the relationship of SPLs in P. suffruticosa and Arabidopsis suggested that they can be classified into six groups, and PsSPLs were highly correlated with Arabidopsis SPLs counterparts in the same group. Cis-element of promoter region analysis suggested that PsSPL genes play roles in physiological processes and developmental events. Expression analysis indicated that most PsSPL genes exhibited high expression levels in the tissues and organs examined here. The increasing expression levels of PsSPL1, PsSPL2, PsSPL8, PsSPL9, PsSPL12, and PsSPL16, and decreasing expression levels of PsSPL1A and PsSPL1B in buds over time suggested that they were probably regulated by the juvenile-to-adult phase transition. In addition, the expression profiles of PsSPL genes in different developmental buds and seeds suggested that PsSPL2, PsSPL3, PsSPL9, PsSPL10, PsSPL13, and PsSPL13A were important genes for regulating the flowering time of the tree peony; PsSPL2 and PsSPL8 might play a role in suppressing lateral bud development, and PsSPL2, PsSPL13, and PsSPL14 positively controlled grain size and number, and pod branching. These results provide a foundation for future functional analysis of PsSPL genes in tree peony growth and development.

Major Fatty Acid Compositions and Antioxidant Activity of Cultivated Paeonia ostii under Different Nitrogen Fertilizer Application.

Paeonia ostii is now being extensively planted for oil extraction in China, which is recognized as a single oil-use tree peony cultivar and commonly called 'Fengdan'. This study investigated the effects of nitrogen fertilizer on oil yield, fatty acid compositions and antioxidant activity of P. ostii. Oil yield (33.46 %), oleic acid (25.12 %), linoleic acid (29.21 %) and α-linolenic acid (43.12 %) reached the maximum at N450 treatment, with significant differences compared with other treatments (P<0.05). Furthermore, strong antioxidant activity with low DPPHIC50 value (19.43±1.91 µg mL-1 ) and large ABTS value (1216.53±30.21 µmol Trolox g-1 ) and FRAP value (473.57±9.11 µmol Trolox g-1 ) was also observed at N450. Palmitic acid (5.57 %) and stearic acid (2.02 %) reached a maximum at N375, but not significant with N450 (P<0.05). Nitrogen fertilizer could promote oil yield, fatty acid accumulation and antioxidant activity, and N450 (450 kg ha-1 ) is recommended as the optimum application for P. ostii.

Major Fatty Acid Profiles and Bioactivity of Seed Oils from Ten†Tree Peony Cultivars as a Potential Raw Material Source for the Cosmetics and Healthy Products.

As a new woody oleaginous crop, tree peony is now being widely developed and utilized, which attributed to the outstanding oil-use features regarding the fatty acid profiles and bioactivity. The major fatty acid profiles and bioactivity of seed oils in ten tree peony varieties collected from a common garden were investigated in the present study. The results showed that the oil yields, fatty acid profiles, bioactivity of seed oils existed significant variations among ten tree peony varieties (P<0.05). Considered the application value, 'Fengdan' (FD) and 'Ziban' (ZB) was the optimal resources as the high oil yields, rich unsaturated fatty acids especially high α-linolenic acid of 40.46 %, great antioxidant activity with low IC50 values, high ABTS and FRAP values, and strong antimicrobial activity with high DIZ and low MIC/MBC values. The study also confirmed seed oil of tree peony as the potential raw materials sources in functional food, pharmaceuticals and cosmetics for human health.

Effects of Growing Location on the Contents of Main Active Components and Antioxidant Activity of Dasiphora fruticosa (L.) Rydb. by Chemometric Methods.

Traditional Chinese Medicine (TCM) is a very important raw material source for natural medicines in China. The content and activity of active component are main indexes that evaluate the quality of TCM, however, they may vary with environmental factors. In this study, the effects of environmental factors on the active component contents and antioxidant activity of Dasiphora fruticosa collected from the five main growing areas of China were investigated. The contents of tannin, total flavonoids and rutin were determined to be 7.65 - 10.69%, 2.30 - 5.39% and 0.18 - 0.81%, respectively. Antioxidant activity was determined by DPPH assay, with the DPPH IC50 values ranged from 8.791 to 32.534 µg mL-1 . In order to further explore the cause of these significant geographical variations, the chemometric methods including correlation analysis, principal component analysis, gray correlation analysis and path analysis were applied. The results showed that environmental factors had significant effect on the contents of active components and antioxidant activity. Rapidly available phosphorus (RAP) and rapidly available nitrogen (RAN) were common dominant factors, and a significant positive action existed between RAP and active components and antioxidant activity (P < 0.05). Contributed by their high active components and strong antioxidant activity, Bange in Tibet and Geermu in Qinghai Province were selected as a favorable growing location, respectively.

Screening of Genes Related to Early and Late Flowering in Tree Peony Based on Bulked Segregant RNA Sequencing and Verification by Quantitative Real-Time PCR.

Tree peony (Paeonia suffruticosa Andrews) is a perennial woody shrub bearing large and colorful flowers. However, the flowering period is short and relatively uniform, which to an important extent hinders the cultivation and exploitation of ornamental peonies. In this study, the segregation of an F1 population derived from P. ostti 'Feng Dan' (an early-flowering cultivar) × P. suffruticosa 'Xin Riyuejin' (a late-flowering cultivar) was used to screen and analyze candidate genes associated with flowering period of the two parents. Extreme early- and late-flowering genotypes of the F1 population at full-bloom stage were sampled to establish an early-flowering mixed pool (T03), a late-flowering mixed pool (T04), a late-flowering male pool (T01), and an early-flowering female pool (T02), using the Sequencing By Synthesis (SBS) technology on the Illumina HiSeq TM2500 platform. A total of 56.51 Gb of clean reads data, comprising at least 87.62% of Quality30 (Q30), was generated, which was then combined into 173,960 transcripts (N50 = 1781) and 78,645 (N50 = 1282) unigenes, with a mean length of 1106.76 and 732.27 base pairs (bp), respectively. Altogether, 58,084 genes were annotated by comparison with public databases, based on an E-value parameter of less than 10-5 and 10-10 for BLAST and HMMER, respectively. In total, 291 unigene sequences were finally screened out by BSR-seq (bulked segregant RNA-seq) association analysis. To validate these unigenes, we finally confirmed seven unigenes that were related to early and late flowering, which were then verified by quantitative real-time PCR (qRT-PCR). This is the first reported study to screen genes associated with early and late flowering of tree peony by the BSA (bulked sample analysis) method of transcriptome sequencing, and to construct a high-quality transcriptome database. A set of candidate functional genes related to flowering time was successfully obtained, providing an important genetic resource for further studies of flowering in peony and the mechanism of regulation of flowering time in tree peony.

Complete Chloroplast Genome Sequence and Phylogenetic Analysis of Paeonia ostii.

Paeonia ostii, a common oil-tree peony, is important ornamentally and medicinally. However, there are few studies on the chloroplast genome of Paeonia ostii. We sequenced and analyzed the complete chloroplast genome of P. ostii. The size of the P. ostii chloroplast genome is 152,153 bp, including a large single-copy region (85,373 bp), a small single-copy region (17,054 bp), and a pair of inverted repeats regions (24,863 bp). The P. ostii chloroplast genome encodes 111 genes, including 77 protein-coding genes, four ribosomal RNA genes, and 30 transfer RNA genes. The genome contains forward repeats (22), palindromic repeats (28), and tandem repeats (24). The presence of rich simple-sequence repeat loci in the genome provides opportunities for future population genetics work for breeding new varieties. A phylogenetic analysis showed that P. ostii is more closely related to Paeonia delavayi and Paeonialudlowii than to Paeoniaobovata and Paeoniaveitchii. The results of this study provide an assembly of the whole chloroplast genome of P. ostii, which may be useful for future breeding and further biological discoveries. It will provide a theoretical basis for the improvement of peony yield and the determination of phylogenetic status.

Reverse transcriptase domain sequences from tree peony (Paeonia suffruticosa) long terminal repeat retrotransposons: sequence characterization and phylogenetic analysis.

Tree peony is an important horticultural plant worldwide of great ornamental and medicinal value. Long terminal repeat retrotransposons (LTR-retrotransposons) are the major components of most plant genomes and can substantially impact the genome in many ways. It is therefore crucial to understand their sequence characteristics, genetic distribution and transcriptional activity; however, no information about them is available in tree peony. Ty1-copia-like reverse transcriptase sequences were amplified from tree peony genomic DNA by polymerase chain reaction (PCR) with degenerate oligonucleotide primers corresponding to highly conserved domains of the Ty1-copia-like retrotransposons in this study. PCR fragments of roughly 270 bp were isolated and cloned, and 33 sequences were obtained. According to alignment and phylogenetic analysis, all sequences were divided into six families. The observed difference in the degree of nucleotide sequence similarity is an indication for high level of sequence heterogeneity among these clones. Most of these sequences have a frame shift, a stop codon, or both. Dot-blot analysis revealed distribution of these sequences in all the studied tree peony species. However, different hybridization signals were detected among them, which is in agreement with previous systematics studies. Reverse transcriptase PCR (RT-PCR) indicated that Ty1-copia retrotransposons in tree peony were transcriptionally inactive. The results provide basic genetic and evolutionary information of tree peony genome, and will provide valuable information for the further utilization of retrotransposons in tree peony.

iTRAQ proteome analysis reveals the underling mechanisms of foliage zinc-spraying to improve photosynthetic capacity and seed yields of Peaonia ostii 'Fengdan'.

Zinc (Zn) deficiency is a significant nutritional limitation to crop yield globally, particularly in calcareous soil environments. Tree peony of Peaonia ostii 'Fengdan' is regarded as an oil crop due to its seeds rich in alpha-linolenic acid, a beneficial compound for health promotion. However, low seed yield remains a primary challenge in attaining sufficient seed oil from tree peony. In this study, Zn fertilization was applied to soil or foliage of P. ostii 'Fengdan' in the growth period before fruit development. Our findings reveal that foliar Zn-spraying, as opposed to soil application, proves to be a more effective method for augmenting seed yield, Zn accumulation and photosynthetic capacity in 'Fengdan'. Comparative analyses of the leaf proteome of 'Fengdan' using iTRAQ profiling under foliar Zn-spraying identified 115 differentially expressed proteins (DEPs), including 36 upregulated proteins, which likely contribute to the observed increase in seed yields of 'Fengdan' caused by foliage Zn-spraying. Specifically, Zn2+ stimulation of phosphatidylinositol signaling initiates a cascade of metabolic regulations. Firstly, ATP synthesis promotes leaf photosynthetic capacity, facilitated by improved sucrose metabolism through upregulated pullulanase and 1,4-alpha-glucan-branching enzyme. Furthermore, lipid synthesis and transport are facilitated by upregulated lipoyl synthase and plastid lipid-associated proteins. Additionally, DEPs involved in secondary metabolism are upregulated in the production of various metabolites conducive to 'Fengdan' growth. Overall, our results demonstrate that foliage Zn-spraying enhances seed yield in P. ostii 'Fengdan' by elevating Zn content and secondary metabolite synthesis in leaves, thereby augmenting leaf photosynthetic capacity and lipid synthesis. This study provides an effective way to increase seed yield of tree peony by exogenous Zn application.

Tree peony seed oil alleviates hyperlipidemia and hyperglycemia by modulating gut microbiota and metabolites in high-fat diet mice.

With the changes of people's lifestyle, hyperlipidemia and hyperglycemia which were induced from a diet high in both fat and sugar have become serious health concerns. Tree peony seed oil (PSO) is a novel kind of edible oil that shows great potential in the food industry because of its high constituent of unsaturated fatty acids. Based 16S rRNA and gut untargeted metabolomics, this study elucidated that the mechanism of PSO regulating blood glucose (Glu) and lipids. The impact of PSO on gut microbiota balance and gut metabolites of mice with a high-fat diet (HFD) was evaluated. The findings indicated that PSO decreased HFD mice's body weight and fat accumulation, ameliorating the levels of blood lipid, reduced liver fat vacuole levels. What's more PSO modulated the proportion of gut microbiota in HFD mice and enhanced the abundance of probiotics. Furthermore, untargeted metabolomic analysis revealed that PSO not only impacted the generation of short-chain fatty acids (SCFAs) by gut microorganism and altered metabolic pathway but exerted influence on secondary bile acids (BA), amino acid metabolism, and various other metabolites. These results suggested that PSO has the potential function for mitigating HFD-induced hyperlipidemia and hyperglycemia by regulating gut microbiota and host metabolism.

Functional Characterization of PoEP1 in Regulating the Flowering Stage of Tree Peony.

The tree peony, a traditional flower in China, has a short and concentrated flowering period, restricting the development of the tree peony industry. To explore the molecular mechanism of tree peony flowering-stage regulation, PoEP1, which regulated the flowering period, was identified and cloned based on the transcriptome and degradome data of the early-flowering mutant Paeonia ostii 'Fengdan' (MU) and Paeonia ostii 'Fengdan' (FD). Through bioinformatics analysis, expression pattern analysis, and transgene function verification, the role of PoEP1 in the regulation of tree peony flowering was explored. The open-reading frame of PoEP1 is 1161 bp, encoding 386 amino acids, containing two conserved domains. PoEP1 was homologous to the EP1 of other species. Subcellular localization results showed that the protein was localized in the cell wall and that PoEP1 expression was highest in the initial decay stage of the tree peony. The overexpression of PoEP1 in transgenic plants advanced and shortened the flowering time, indicating that PoEP1 overexpression promotes flowering and senescence and shorten the flowering time of plants. The results of this study provide a theoretical basis for exploring the role of PoEP1 in the regulation of tree peony flowering.

Identification of Floral Volatile Components and Expression Analysis of Controlling Gene in Paeonia ostii 'Fengdan' under Different Cultivation Conditions.

In order to explore the release rule of floral volatile substances and the diurnal variation of different flower development stages of Paeonia ostii 'Fengdan' in potted and ground-planted conditions, dynamic headspace adsorption combined with gas chromatography-mass spectrometry(GC-MS) was used to analyze the dynamic changes in floral volatile components and contents. Quantitative real-time PCR (qRT-PCR) was used to analyze changes in flower fragrance-regulating genes PsPAL, PsTPSs, and PsbHLH at different flower development stages and a daily change process at the full-blooming stage. The results show that there were differences in aroma components and contents of Paeonia ostii 'Fengdan' at different flower development stages and different time quantum of every day. There were 25 and 28 aroma components identified in 7 flower development stages of tree peonies planted in pots and in the field, respectively, and 23 and 22 aroma components identified at different time quantum of the day, of which the largest and highest content was alkanes. The main characteristic aroma substances were (E)-ß-ocimene, 1,3,5-trimethoxybenzene, 2,4-di-tert-butylphenol, methyl jasmonate, nerol, and cinnamyl alcohol; released amounts of the abovementioned substances varied depending on the development stage and the time of the day. The expression of flower fragrance-controlling genes (PsPAL, PsTPSs, and PsbHLH) in tree peonies varied greatly in different conditions. The results of this study provide a valuable resource to investigate floral fragrance formation in tree peonies.

The efficient removal of congo red and ciprofloxacin by peony seeds shell activated carbon with ultra-high specific surface area.

Preparation of high-performance activated carbon from agroforestry waste biomass can effectively improve the shortcomings of traditional biomass carbon performance. Using the waste biomass peony seeds shell (PSS) as the precursors in this study, high performance activated carbon was prepared by the KOH two-step activation method and used to remove congo red (CR) and ciprofloxacin (CIP) in water pollution. The obtained PSS-based activated carbons (PSACs) were characterized by SEM, EDS, N2 adsorption-desorption isotherm, FTIR, and XRD methods. The results showed that the activated carbon at 700 °C (PSAC-700) had an ultra-high specific surface area (2980.96 m2/g), excellent micropore volume (1.12 cm3/g), and abundant surface functional groups. The results of adsorption performance revealed that PSAC-700 exhibited excellent adsorption capacity for CR (qmax = 2003.2 mg/g) and CIP (qmax = 782.3 mg/g), which was superior to the carbon-based adsorbents reported reviously in the literature. Langmuir model could well describe the adsorption process of PSACs for CR and CIP, indicating that the pollutant molecules were uniformly adsorbed on the surface monolayer. The regeneration experiment suggested that after three cycles, the adsorption capacities of PSAC-700 for CR and CIP reached 1814 mg/g and 697 mg/g, respectively, with good repeatability. The preparation of PSAC-700 in this study has high adsorption capacity and strong application, which is an ideal material for wastewater purification adsorbent and has broad application prospect.