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Selenium (Se) is an essential trace element for human physiological metabolism. The application of organic Se as a source to cultivate Se-rich plants for micronutrient supplementation has been receiving increasing attention. In our study, a bacterial strain named H1 was isolated from the soil in Heilongjiang Province, China, and under optimal culture conditions, the unit Se content could reach 3000 μg·g−1 and its 16S ribosomal DNA sequence seemed to be a new molecular record of an Enterobacter species. After the domestication of Se tolerance and Se-rich experiments, H1 can be used as a Se source for cultivation of Se-rich Auricularia auricula. The results showed that soluble protein, soluble sugar, free amino acid and vitamin C contents in Auricularia auricula were notably increased by 28.7%, 21.8%, 32.5% and 39.2% under the treatment of Se concentration of 0.24 mg·kg−1, respectively. These findings enhance our understanding that H1 is more conducive to Se uptake and nutrient accumulation. [ABSTRACT FROM AUTHOR]

Paeonia ostii is an important economic oil and medicinal crop. Its anthers are often used to make tea in China with beneficial effects on human health. However, the metabolite profiles, as well as potential biological activities of P. ostii anthers and the pollen within anthers have not been systematically analyzed, which hinders the improvement of P. ostii utilization. With comprehensive untargeted metabolomic analysis using UPLC-QTOF-MS, we identified a total of 105 metabolites in anthers and pollen, mainly including phenylpropanoids, polyketides, organic acids, benzenoids, lipids, and organic oxygen compounds. Multivariate statistical analysis revealed the metabolite differences between anthers and pollen, with higher carbohydrates and flavonoids content in pollen and higher phenolic content in anthers. Meanwhile, both anthers and pollen extracts exhibited antioxidant activity, antibacterial activity, α-glucosidase and α-amylase inhibitory activity. In general, the anther stage of S4 showed the highest biological activity among all samples. This study illuminated the metabolites and biological activities of anthers and pollen of P. ostii, which supports the further utilization of them. [ABSTRACT FROM AUTHOR]

The tree peony, a novel woody oil crop extensively cultivated in China, necessitates further investigation into artificial pollination technology to enhance seed yield. In this study, we conducted artificial pollination experiments with 6-year-old Paeonia ostii 'Feng Dan' seedings for suitable pollen sources, pollen concentration, pollination timing, and pollination frequency. By evaluating seed yields, active ingredients, and oil quality, we derived the following significant conclusions. Firstly, compared to natural pollination, artificial pollination could significantly increase the fruit diameter by 13.94–27.58%, seed yields by 35.17–58.99%, and oil content by 6.45–7.52% in tree peonies. In active ingredients, seeds produced by pollen from Hantai County significantly enhanced starch content (by 48.64%), total phenols (by 41.18%) and antioxidant capacity (by 54.39%). In oil quality, seeds produced by pollen from Heyang County exhibited the highest α-linolenic acid and total fatty acid content with enhancements of 1.68%, 7.41%, and 8.48%. Secondly, hand pollination with pure pollen significantly increased seed yield by 58.99%, total phenol content by 40.97%, antioxidant capacity by 54.39%, and oil content by 1.53% compared to natural pollination. Thirdly, pollination at 2/3 bloom range significantly increased seed number by 63.08% and yield by 45.61% compared to natural pollination. Finally, the effect of one, two, and three pollination events had no difference in seed yield. So, to summarize, applying a 100% concentration of allochthonous pollen once is recommended when the bloom range is more than two thirds. [ABSTRACT FROM AUTHOR]

Deterministic polishing based on jet electrochemical machining (Jet-ECM) is a stress-free machining method for low-rigidity and ultra-precision workpieces. The nozzle is equivalent to a special tool in deterministic polishing, and the workpiece material is removed using the mechanism of electrochemical dissolution at the position where the nozzle passes. By precisely regulating the nozzle's movement speed and dwell time, the quantity of material removed from the workpiece at a designated position can be finely adjusted. With this mechanism, the improvement of the workpiece shape accuracy can be achieved by planning the nozzle trajectory and nozzle movement speed. However, due to the positioning errors of the polishing device, the actual position of the nozzle may deviate from the theoretical position, resulting in errors in material removal amount, which affects the accuracy and stability of the polishing process. This study established a mathematical model to analyze the influence of nozzle positioning errors in deterministic polishing based on Jet-ECM. This model has been used to design a specific deterministic polishing device based on Jet-ECM. With the proposed deterministic polishing device, the surface shape of the workpiece is converged. The surface peak-to-valley (PV) value of the φ 50 mm workpiece (valid dimensions = 90% of the central region) indicated that the shape error of the surface was reduced from 2.67 μm to 1.24 μm in 34 min. The power spectral density (PSD) method was used to evaluate the height distribution and height characteristics of the workpiece surface. The results show that the low frequency spatial error is reduced significantly after processing. This study improves the accuracy of the stress-free deterministic polishing methods and further expands the use of deterministic polishing in industry. [ABSTRACT FROM AUTHOR]

This study aimed to explore the evolution of Jingdang and Famen towns near the Zhouyuan site, the capital city site of the Western Zhou Dynasty in China, to elucidate the relationship between township development and the essential ancient relics conservation areas. Based on the remote sensing satellite images from 1982 to 2022, combining with historical demographic data, this study used four methods, including land use classification, land use transfer matrix, landscape pattern center of gravity changes, and population count statistics, to study the spatial–temporal evolution of land, population, and ecology in the region over the past 40 years. The results showed that under the strict relic conservation regimen, these two towns are in a declining stage. To improve their decaying status, some potential strategies valuable for township development are proposed to balance the relationship between relic conservation and township development for their mutual benefit and coexistence. [ABSTRACT FROM AUTHOR]

Paeonia ostii 'Feng Dan' is widely cultivated in China for its ornamental, medicinal, and edible properties. The whole plant of tree peony is rich in bioactive substances, while the comprehensive understanding of metabolites in the leaves is limited. In this study, an untargeted metabolomics strategy based on UPLC-ESI-TOF-MS was conducted to analyze the dynamic variations of bioactive metabolites in P. ostii 'Feng Dan' leaves during development. A total of 321 metabolites were rapidly annotated based on the GNPS platform, in-house database, and publications. To accurately quantify the selected metabolites, a targeted method of HPLC-ESI-QQQ-MS was used. Albiflorin, paeoniflorin, pentagalloylglucose, luteolin 7-glucoside, and benzoylpaeoniflorin were recognized as the dominant bioactive compounds with significant content variations during leaf development. Metabolite variations during the development of P. ostii 'Feng Dan' leaves are greatly attributed to the variations in antioxidant activities. Among all tested bacteria, the leaf extract exhibited exceptional inhibitory effects against Streptococcus hemolytis-β. This research firstly provides new insights into tree peony leaves during development. The stages of S1–S2 may be the most promising harvesting time for potential use in food or pharmaceutical purposes. [ABSTRACT FROM AUTHOR]

Aromatic plants of the family Lamiaceae, especially of the genus Thymus, have promising antioxidant applications in pharmacology, medicine, food, cosmetology, and aromatherapy. Hydrosols (HDs) were extracted by hydrodistillation from seven species of Lamiaceae, including Thymus vulgaris, Thymus mongolicus, Mentha × piperita, Melissa officinalis, Rosmarinus officinali, Salvia elegans, and Leonurus artemisia. In total, 369 volatile components were determined and analyzed by gas chromatography–mass spectrometry (GC-MS). Among them, alcohols (2.86–28.48%), ethers (2.46–10.69%), and phenols (0.11–21.78%) constituted a large proportion, mainly linalool (0.28–19.27%), eucalyptol (0.16–6.97%), thymol (0–19.54%), and carvacrol (0–26.82%). Multivariate statistical analyses were performed and 27 differential metabolites were screened. Three different methods (ABTS+•, DPPH•, and FRAP) were used to determine the in vitro antioxidant activity of seven HDs. Thymus vulgaris hydrosols (Tv HDs) and Thymus mongolicus hydrosols (Tm HDs) had the strongest antioxidant activity and their stronger antioxidant capacity was related to their high levels of phenolic constituents, mainly thymol. The antioxidant activity of the other five Lamiaceae HDs was associated with their high alcohol (mainly linalool and eucalyptol) content, and the alcohol constituents may synergistically affect their antioxidant capacity. Therefore, the present study suggests that Lamiaceae plants can be utilized as antioxidant products or antioxidants in different industrial sectors including pharmaceuticals, food, cosmetics, and agrochemicals. [ABSTRACT FROM AUTHOR]

The Qinling Mountains north slope region constitutes a vital terrestrial ecosystem reserve within China. This study employs land use and land cover (LULC) data spanning from 1990 to 2020. Utilizing methodologies encompassing land use classification, transfer matrix analysis, and the application of the PLUS and InVEST models, this research endeavors to elucidate the spatial-temporal dynamics of land use patterns and associated carbon storage in the region. These analyses are conducted within the context of four prospective scenarios: Natural Development Priority, Arable Land Protection Priority, Ecological Protection Priority, and Urban Development Priority, all projected onto the landscape for 2030. Notably, our findings reveal a consistent decline in carbon storage across all four scenarios for 2030 compared to the baseline year 2020. This stark reality presents substantial challenges to achieving the region's targets of carbon peaking and eventual carbon neutrality. Furthermore, this paper meticulously delineates six key drivers contributing to this decline in carbon storage. In conclusion, it proffers nine strategic recommendations aimed at augmenting carbon storage, with an overarching objective of establishing a harmonized mechanism capable of balancing urban development, safeguarding cultivated land, fortifying ecological preservation, and enhancing carbon sequestration within the area. [ABSTRACT FROM AUTHOR]

The classification of drilling conditions is a crucial task in the drilling process, playing a vital role in improving drilling efficiency and reducing costs. In this study, we propose an improved stacking ensemble learning algorithm with the objective of enhancing the performance of drilling conditions classification. Additionally, this algorithm aims to have a positive impact on automated drilling time estimation and the continuous improvement of efficiency. In our experimental setup, we employed various base learners, such as random forests, support vector machine, and the K-nearest neighbors algorithm, as initial models for the task of drilling conditions classification. To improve the model's expressive power and feature relevance specifically for this task, we enhanced the meta-model component of the stacking algorithm by incorporating feature engineering techniques. The experimental results show that the improved ensemble learning algorithm achieves an accuracy and recall rate of 97% and 98%, respectively. Through continuous improvement in drilling operations, the average sliding time is reduced by 21.1%, and the average Rate of Penetration (ROP) is increased by 15.65%. This research holds significant importance for engineering practice in the drilling industry, providing robust support for optimizing and enhancing the drilling process. [ABSTRACT FROM AUTHOR]

Paeonia ostii is an important woody oil crop mainly cross-pollinated. However, the low yield has become an important factor restricting the industrial development of P. ostii. Cross-pollination has become one of the important measures to increase the seed yield. Therefore, conservation of pollen with high vitality is crucial to ensure successful pollination of P. ostii. In this study, we found an effective methodological system to assess the viability, ability to germinate, and optimal storage conditions of P. ostii pollen grains. The optimal medium in vitro was 50 g/L sucrose, 100 mg/L boric acid, 50 g/L PEG6000, 100 mg/L potassium nitrate, 300 mg/L calcium nitrate, and 200 mg/L magnesium sulfate at pH 5.4. Optimal germination condition in vitro was achieved at 25 °C for 120 min, allowing easy observation of the germination percentage and length of the pollen tubes. In addition, the viability of pollen grains was assessed by comparing nine staining methods. Among them, MTT, TTC, benzidine-H2O2, and FDA were effective to distinguish between viable and non-viable pollen, and the results of the FDA staining method were similar to the pollen germination percentage in vitro. After evaluation of pollen storage, thawing and rehydration experiments showed that thawing at 4 °C for 30 min and rehydration at 25 °C for 30 min increased the germination percentage of pollen grains stored at low temperatures. The low-temperature storage experiments showed that 4 °C was suitable for short-term storage of P. ostii pollen grains, while −80 °C was suitable for long-term storage. This is the first report on the in vitro germination, viability tests, and storage of P. ostii pollen grains, which will provide useful information for P. ostii germplasm conservation and artificial pollination. [ABSTRACT FROM AUTHOR]

Tree peonies (Paeonia Section Moutan)—including nine wild species, which belong to subsections Vaginatae and Delavayanae—are economically important plants with ornamental, nutritional, and medicinal applications. In this study, for the first time, we determined the bioactive components and antioxidant activities and antibacterial activities of the newly grown leaves of nine wild tree peony species (WTPS). A total of 276 bioactive components were identified through non-targeted metabolomics; more than 80% of the 276 metabolites identified are terpenoids and flavonoids. A total of 42 differential metabolites were quantitatively determined. The main differential metabolites were Paeoniflorin, Luteoloside, Hyperin, Apigenin-7-glucoside, Rhoifolin, and Cantharidin. Such a high terpenoid and flavonoid content of the leaf extracts renders them as species with strong antibacterial capacities, and most of the bacteria tested showed greater sensitivity derived from the members of subsection Vaginatae than those of subsection Delavayanae. All WTPS have significant antioxidant activity; this activity is attributed to high levels of the total phenolic content (TPC) and total flavonoid content (TFC), of which, among the nine WTPS, P. lutea has the strongest antioxidant capacity. Our results provided a theoretical basis for the in-deep application of tree peony leaves for food, medical, and pharmaceutical industries. [ABSTRACT FROM AUTHOR]

In the past few decades, human activities have caused the emission of large amounts of carbon dioxide, which has severely impacted the Earth's ecosystem and human health. Therefore, carbon reduction has become the focus of global attention. In this study, the Zhouyuan region of China, which is rich in ancient remains, is taken as an example. Based on the land use characteristics in 1990, 2000, 2010, and 2020, the spatial-temporal evolution of land use and carbon storage in the Zhouyuan region is simulated using four methods, including land use classification, land use transfer maps, patch-level land-use simulation (PLUS), and the integrated valuation of ecosystem services and trade-offs (InVEST) models under three scenarios, including the natural development scenario, urban development priority, and heritage conservation priority in 2030. According to the results, the carbon storage in the area in 2030 under all three scenario simulations has decreased compared with 2020, indicating that the region faces great challenges in achieving its targets of carbon peak and carbon neutrality. The paper points out four causes for the decrease in carbon storage, and five suggestions for increasing carbon storage are proposed, such as developing a carbon storage master plan, applying energy-saving technologies, establishing an ecological substitution mechanism, and so on. Through the study of carbon storage in the Zhouyuan region, this paper hopes to establish a mechanism to balance urban development, heritage conservation, and carbon sinks on the one hand, and encourage more scholars to participate in the study of carbon sinks in areas rich in ancient remains, so as to to jointly promote their healthy development on the other. [ABSTRACT FROM AUTHOR]

Flower scent is one of the main ornamental characteristics of herbaceous peony, and the improvement of flower fragrance is a vital objective of herbaceous peony breeding. In this study, 87 herbaceous peony cultivars were divided into three groups (no/light fragrance, medium fragrance, and strong fragrance) based on their sensory evaluation scores, and 16 strong fragrance cultivars and one no fragrance cultivar were selected for subsequent analysis. Sixty-eight volatile components were detected in these 17 cultivars based on solid-phase microextraction (SPME) and gas chromatography/mass spectrometry (GC/MS), and 26 types were identified as important scent components. They were composed of terpenoids, benzenoids/phenylpropanoids, and fatty acid derivatives. According to the content and odor threshold of these main aroma components, the characteristic aroma substances of herbaceous peony were identified, including linalool, geraniol, citronellol, and phenylethyl alcohol (2-PE). The cultivars of strong scented herbaceous peony were divided into three types: rose scent, lily scent, and mixed scent. We explored the possible key genes of characteristic aroma substances in herbaceous peony petals with different odors through the qRT-PCR. The key genes encoding monoterpene biosynthesis were found to be PlDXS2, PlDXR1, PlMDS1, PlHDR1, PlGPPS3, and PlGPPS4. In addition, the linalool synthase (LIS) gene and the geraniol synthase (GES) gene were also found. PlAADC1, PlPAR1, and PlMAO1, related to the biosynthesis of 2-PE were detected, and the synthetic pathway of 2-PE was speculated. In conclusion, these findings revealed that the difference in gene expression of monoterpene and 2-PE synthesis pathway was related to the difference in the fragrance of herbaceous peony. This study explored the releasing pathway of herbaceous peony characteristic aroma substances and provided key genetic resources for fragrance improvement. [ABSTRACT FROM AUTHOR]

Tree peony is a "spring colored-leaf" plant which has red leaves in early spring, and the red color of the leaves usually fades in late spring. Flavonols are one subgroup of flavonoids, and they affect the plant organs' color as co-pigments of anthocyanins. To investigate the color variation mechanism of leaves in tree peony, PqMYBF1, one flavonol biosynthesis-related MYB gene was isolated from Paeonia qiui and characterized. PqMYBF1 contained the SG7 and SG7-2 motifs which are unique in flavonol-specific MYB regulators. Subcellular localization and transactivation assay showed that PqMYBF1 localized to the nucleus and acted as a transcriptional activator. The ectopic expression of PqMYBF1 in transgenic tobacco caused an observable increase in flavonol level and the anthocyanin accumulation was decreased significantly, resulting in pale pink flowers. Dual-luciferase reporter assays showed that PqMYBF1 could activate the promoters of PqCHS, PqF3H, and PqFLS. These results suggested that PqMYBF1 could promote flavonol biosynthesis by activating PqCHS, PqF3H, and PqFLS expression, which leads metabolic flux from anthocyanin to flavonol pathway, resulting in more flavonol accumulation. These findings provide a new train of thought for the molecular mechanism of leaf color variation in tree peony in spring, which will be helpful for the molecular breeding of tree peony with colored foliage. [ABSTRACT FROM AUTHOR]

The canopy volume of fruit trees is an important input for the precise and varying application of pesticides in orchards. The fixed mesh division method is mostly used to calculate canopy volumes with variable target-oriented spraying. To reduce the influence of the working speed on the detection accuracy under a fixed mesh width division, the cuboid accumulation of divided areas (CADAs), which is a light detection and ranging (LiDAR) online detection method for a fruit tree canopy volume based on dynamic mesh division, is proposed in this paper. In the method, the area is divided according to the number of unilateral nozzles of the sprayer in the canopy height direction of the fruit tree, and the mesh width is dynamically adjusted according to the change in the working speed in the moving direction of the sprayer. To verify the accuracy and applicability of the method, the simulation canopy and peach tree canopy detection experiments were carried out. The test results show that the CADA method can be used to calculate the contour and volume of the canopy. However, detection errors easily occur at the edge of the canopy, resulting in a detection error of 8.33% for the simulated canopy volume. The CADA method has a good detection accuracy under different moving speeds and fruit tree canopy sizes. At a speed of 1 m/s, the detection accuracy of the canopy volume reaches 99.18%. Compared with the existing canopy volume calculation methods based on the alpha-shape algorithm and canopy meshing-profile characterization (CMPC), the detection accuracy of the CADA method is 2.73% and 7.22% better, respectively. This method can not only reduce the influence of the moving speed on the detection accuracy of the canopy volume, but also improve the detection accuracy. Thus, this method can provide theoretical support for the research and development of target-oriented variable spraying control systems for orchards. [ABSTRACT FROM AUTHOR]

Pollen characteristics have some significance for plant taxonomy classification. We intend to explore a more concise index value for the subsection taxonomy with the pollen morphology and pollen viability determined from all nine wild tree peony species, including 18 populations native to China. We observed the pollen morphologic characters by scanning electron microscopy and measured the pollen viability in vitro. The results showed that the pollen polar length is the decisive characteristic in distinguishing the two subsections in section Moutan belonging to Paeoniaceae. The pollen polar length of five species belonging to subsect. Vaginatae is longer than 43 μm, while that of the four species belonging to subsect. Delavayanae is shorter than 43 μm. Meanwhile, the differences in pollen viability between the two subsections also play an auxiliary role in the classification of tree peony. The germination rate of the populations in subsect. Vaginatae is mostly greater than those of the populations in subsect. Delavayanae. The pollen germination rate of populations in subsect. Vaginatae is commonly more than 50%, while that of populations in subsect. Delavayanae less than 50%. Our study established taxonomic evidence between subsections in section Moutan and compared the pollen viability of subsect. Vaginatae and subsect. Delavayanae. [ABSTRACT FROM AUTHOR]

Perfluorooctanoic acid (PFOA) that accumulates in wastewater and excess sludge interact with the anaerobes and deteriorate the energy recovery and pollutants removal performance in the anaerobic digestion (AD) system. However, the interaction between PFOA and microbial metabolism in the AD systems remains unclear. This study aimed to clarify the effects and mechanism of PFOA on the AD process as well as the removal pathways of PFOA in an AD system. The results showed that the methane recovery efficiency was inhibited by 7.6–19.7% with the increased PFOA concentration of 0.5–3.0 mg/L, and the specific methanogenesis activity (SMA) was inhibited by 8.6–22.3%. The electron transfer system (ETS) was inhibited by 22.1–37.3% in the PFOA-containing groups. However, extracellular polymeric substance (EPS) gradually increased due to the toxicity of PFOA, and the ratio of protein to polysaccharide shows an upward trend, which led to the formation of sludge aggregates and resistance to the toxic of PFOA. The PFOA mass balance analysis indicated that 64.2–71.6% of PFOA was removed in the AD system, and sludge adsorption was the main removal pathway, accounting for 36.1–61.2% of the removed PFOA. In addition, the anaerobes are proposed to have the potential to reduce PFOA through biochemical degradation since 10.4–28.2% of PFOA was missing in the AD system. This study provides a significant reference for the treatment of high-strength PFOA-containing wastes. [ABSTRACT FROM AUTHOR]

Gallotannins (GTs) are a series of hydrolyzable tannins with multiple health-promoting effects. In this study, an integrated liquid chromatography tandem mass spectrometry (LC–MS/MS) strategy was developed for unveiling the spatial distribution pattern of GTs in the emerging oilseed crops Paeonia rockii and P. ostii. According to the fragmentation behavior of the representative GT (1,2,3,4,6-penta-O-galloyl-β-D-glucose, PGG), the diagnostic neutral loss (NL) of 170 Da was chosen for the non-targeted screening of GT precursors. Simultaneously, the tandem mass spectrometry spectrum (MS/MS) information was acquired through an enhanced product ion (EPI) scan. Nine major GTs were identified in tree peony. To quantify the targeted GTs in different tissues of tree peony, we established a multiple reaction monitoring (MRM)–enhanced product ion (EPI)-based pseudo-targeted approach under the information-dependent acquisition (IDA) mode. The quantitative results show that the GT compounds were ubiquitous in tree peony plants with diverse structures. The typical GT PGG was mainly distributed in roots, leaves, and petals. This strategy can also be utilized for metabolite characterization and quantification in other substrates. [ABSTRACT FROM AUTHOR]

To study the mechanical properties of stainless-steel-reinforced concrete (SSRC) columns under eccentric compression, one ordinary reinforced concrete column and eight SSRC columns were designed for eccentric compression load tests. The eccentricity and reinforcement ratio were considered as the variation parameters. The cracking and failure modes of the SSRC columns were studied. The effects of the variation parameters on the longitudinal strain, concrete strain, lateral displacement, and ultimate load were analyzed. The test results demonstrated that the failure modes of SSRC columns under eccentric compression are similar to those of ordinary reinforced columns. Eccentricity significantly affected the failure modes of the SSRC columns. Under the same eccentricity, the reinforcement ratio had negligible effect on the lateral displacement corresponding to the ultimate load. The mechanical properties of SSRC columns under small eccentric compression were better than expected; however, the ultimate loads under large eccentric compression were proposed. The ultimate load–bending moment curves obtained were consistent with the results of the test and finite element analysis. Based on the experimental results, the force characteristic coefficient was set as 2.7 for calculating the long-term crack width. [ABSTRACT FROM AUTHOR]

The pine wood nematode (PWN) Bursaphelenchus xylophilus has caused disastrous losses of pine forests in many countries, and the success of PWN depends strongly on interactions with its insect vectors. Monochamus saltuarius is a newly recorded vector in Northeast China. Feeding (i.e., immature) and egg-laying (i.e., mature) Monochamus spp. target different host plants, and olfactory cues play important roles regarding host choice. Whether infestation with PWN affects olfactory mechanisms in M. saltuarius related to feeding and oviposition is of interest as this may affect the spread of nematodes to new healthy hosts. However, little is known about molecular mechanisms of the olfactory system of M. saltuarius. We identified chemosensory-related genes in adult M. saltuarius and examined the influence of B. xylophilus on the respective expression patterns. Fifty-three odorant-binding proteins (OBPs), 15 chemosensory proteins, 15 olfactory receptors (ORs), 10 gustatory receptors, 22 ionotropic receptors (IRs), and two sensory neuron membrane proteins were identified, and sex bias among non-infested beetles was mainly found with respect to expression of OBPs. Interestingly, OBPs and ORs were markedly down-regulated in male M. saltuarius infested with B. xylophilus, which may reduce olfactory sensitivity of male M. saltuarius and affect the spreading of B. xylophilus to new hosts. Our results will help understand the interactions between B. xylophilus and M. saltuarius, which may lead to the identification of new control targets in the olfactory system of M. saltuarius. [ABSTRACT FROM AUTHOR]

Paeonia qiui is a wild tree peony native to China. Its leaves show a clear purple-red color from the germination to the flowering stage, and it has high leaf-viewing value. A MYB transcription factor gene, designated as PqMYB4, was isolated from leaves of P. qiui based on transcriptome datas. The full-length cDNA of PqMYB4 was 693 bp, encoding 230 amino acids. Sequence alignment and phylogenetic analysis revealed that PqMYB4 was a R2R3-MYB transcription factor clustered with AtMYB4 in Arabidopsis thaliana. Moreover, it contained a C1 motif, an EAR repression motif and a TLLLFR motif in the C-terminal domains, which were unique in transcription repression MYB. Subcellular location analysis showed that PqMYB4 was located in the cell nucleus. PqMYB4 was highly expressed in the late stage of leaf development, and was negatively correlated with the anthocyanin content. The petiole of wild-type Arabidopsis seedlings was deeper in color than the transgenic lines of PqMYB4 and showed a little purple-red color. The seed coat color of Arabidopsis seeds that overexpressed PqMYB4 gene was significantly lighter than that of wild-type seeds. In transgenic Arabidopsis, the expression level of AtCHS, AtCHI, AtDFR and AtANS were down-regulated significantly. These results showed that PqMYB4 was involved in the negative regulation of anthocyanin biosynthesis in tree peony leaves, which can control the anthocyanin pathway genes. Together, these findings provide a valuable resource with which to further study the regulatory mechanism of anthocyanin biosynthesis in the leaf of P. qiui. They also benefit the molecular breeding of tree peony cultivars with colored leaf. [ABSTRACT FROM AUTHOR]

Peony is an important medicinal and ornamental plant widely cultivated in the world. Its seeds as a functional food source have attracted much more attention in recent years, and they are rich in monoterpene glycosides and phenolic compounds. To assess the application value of wild peony seeds, the main chemical composition and content, such as total phenolic content (TPC), total flavonoid content (TFC), total flavanol content (TAC), and α and γ tocopherol content, of the seeds from 12 species and 2 subspecies were systematically explored in the present study. Four different antioxidant assays (DPPH, ABTS, FRAP, and HRSA), antibacterial, and antifungal assays were also performed using various in vitro biochemical methods. The results showed that the seeds of P. delavayi, P. obovata. subsp. obovata, and P. rockii. subsp. rockii had a high content of TPC, TFC, and TAC, respectively. Twenty-five individual chemical compounds were qualitatively and quantitatively measured by HPLC-MS, with paeoniflorin being the most abundant compound in all samples. P. mairei was grouped individually into a group via hierarchical cluster analysis according to its relatively highest monoterpene glycosides and TPC content. This work has provided a basis for the development and utilization of seeds for the selection of wild peony species of dietary interest. [ABSTRACT FROM AUTHOR]

Eukaryotic translation elongation factors are implicated in protein synthesis across different living organisms, but their biological functions in the pathogenesis of cucumber mosaic virus (CMV) and tobacco rattle virus (TRV) infections are poorly understood. Here, we isolated and characterized a cDNA clone, LreEF1A4, encoding the alpha subunit of elongation factor 1, from a CMV-elicited suppression subtractive hybridization library of Lilium regale. The infection tests using CMV remarkably increased transcript abundance of LreEF1A4; however, it also led to inconsistent expression profiles of three other LreEF1A homologs (LreEF1A1–3). Protein modelling analysis revealed that the amino acid substitutions among four LreEF1As may not affect their enzymatic functions. LreEF1A4 was ectopically overexpressed in petunia (Petunia hybrida), and transgenic plants exhibited delayed leaf and flower senescence, concomitant with increased transcription of photosynthesis-related genes and reduced expression of senescence-associated genes, respectively. A compromised resistance to CMV and TRV infections was found in transgenic petunia plants overexpressing LreEF1A4, whereas its overexpression resulted in an enhanced tolerance to salt and drought stresses. Taken together, our data demonstrate that LreEF1A4 functions as a positive regulator in viral multiplication and plant adaption to high salinity and dehydration. [ABSTRACT FROM AUTHOR]

Tree peony (Paeonia section Moutan DC.) species are woody oil crops with high unsaturated fatty acid content, including α-linolenic acid (ALA/18:3; >40% of the total fatty acid). Comparative transcriptome analyses were carried out to uncover the underlying mechanisms responsible for high and low ALA content in the developing seeds of P. rockii and P. lutea, respectively. Expression analysis of acyl lipid metabolism genes revealed upregulation of select genes involved in plastidial fatty acid synthesis, acyl editing, desaturation, and triacylglycerol assembly in seeds of P. rockii relative to P. lutea. Also, in association with ALA content in seeds, transcript levels for fatty acid desaturases (SAD, FAD2, and FAD3), which encode enzymes necessary for polyunsaturated fatty acid synthesis, were higher in P. rockii compared to P. lutea. Furthermore, the overexpression of PrFAD2 and PrFAD3 in Arabidopsis increased linoleic and ALA content, respectively, and modulated the final ratio 18:2/18:3 in the seed oil. In conclusion, we identified the key steps and validated the necessary desaturases that contribute to efficient ALA synthesis in a woody oil crop. Together, these results will aid to increase essential fatty acid content in seeds of tree peonies and other crops of agronomic interest. [ABSTRACT FROM AUTHOR]

Aromatic plants of the family Lamiaceae, especially of the genus Thymus, have promising antioxidant applications in pharmacology, medicine, food, cosmetology, and aromatherapy. Hydrosols (HDs) were extracted by hydrodistillation from seven species of Lamiaceae, including Thymus vulgaris , Thymus mongolicus , Mentha × piperita , Melissa officinalis , Rosmarinus officinali , Salvia elegans , and Leonurus artemisia . In total, 369 volatile components were determined and analyzed by gas chromatography-mass spectrometry (GC-MS). Among them, alcohols (2.86-28.48%), ethers (2.46-10.69%), and phenols (0.11-21.78%) constituted a large proportion, mainly linalool (0.28-19.27%), eucalyptol (0.16-6.97%), thymol (0-19.54%), and carvacrol (0-26.82%). Multivariate statistical analyses were performed and 27 differential metabolites were screened. Three different methods (ABTS +• , DPPH • , and FRAP) were used to determine the in vitro antioxidant activity of seven HDs. Thymus vulgaris hydrosols (Tv HDs) and Thymus mongolicus hydrosols (Tm HDs) had the strongest antioxidant activity and their stronger antioxidant capacity was related to their high levels of phenolic constituents, mainly thymol. The antioxidant activity of the other five Lamiaceae HDs was associated with their high alcohol (mainly linalool and eucalyptol) content, and the alcohol constituents may synergistically affect their antioxidant capacity. Therefore, the present study suggests that Lamiaceae plants can be utilized as antioxidant products or antioxidants in different industrial sectors including pharmaceuticals, food, cosmetics, and agrochemicals.

Tree peony ( Paeonia section Moutan DC.) species are woody oil crops with high unsaturated fatty acid content, including α-linolenic acid (ALA/18:3; >40% of the total fatty acid). Comparative transcriptome analyses were carried out to uncover the underlying mechanisms responsible for high and low ALA content in the developing seeds of P. rockii and P. lutea , respectively. Expression analysis of acyl lipid metabolism genes revealed upregulation of select genes involved in plastidial fatty acid synthesis, acyl editing, desaturation, and triacylglycerol assembly in seeds of P. rockii relative to P. lutea . Also, in association with ALA content in seeds, transcript levels for fatty acid desaturases (SAD, FAD2, and FAD3), which encode enzymes necessary for polyunsaturated fatty acid synthesis, were higher in P. rockii compared to P. lutea . Furthermore, the overexpression of PrFAD2 and PrFAD3 in Arabidopsis increased linoleic and ALA content, respectively, and modulated the final ratio 18:2/18:3 in the seed oil. In conclusion, we identified the key steps and validated the necessary desaturases that contribute to efficient ALA synthesis in a woody oil crop. Together, these results will aid to increase essential fatty acid content in seeds of tree peonies and other crops of agronomic interest.

Evidence on the burden of chronic obstructive pulmonary disease (COPD) morbidity attributable to the interaction between ambient air pollution and temperature has been limited. This study aimed to examine the modification effect of temperature on the association of ambient air pollutants (including particulate matter (PM) with aerodynamic diameter <10 μm (PM 10 ) and <2.5 μm (PM 2.5 ), nitrogen dioxide (NO₂), sulfur dioxide (SO₂), carbon monoxide (CO) and ozone (O₃)) with risk of hospital admissions (HAs) for COPD, as well as the associated morbidity burden in urban areas of Chengdu, China, from 2015 to 2016. Based on the generalized additive model (GAM) with quasi-Poisson link, bivariate response surface model and stratification parametric model were developed to investigate the potential interactions between ambient air pollution and temperature on COPD HAs. We found consistent interactions between ambient air pollutants (PM 2.5 , PM 10 and SO₂) and low temperature on COPD HAs, demonstrated by the stronger associations between ambient air pollutants and COPD HAs at low temperatures than at moderate temperatures. Subgroup analyses showed that the elderly (≥80 years) and males were more vulnerable to this interaction. The joint effect of PM and low temperature had the greatest impact on COPD morbidity burden. Using WHO air quality guidelines as reference concentration, about 17.30% (95% CI: 12.39%, 22.19%) and 14.72% (95% CI: 10.38%, 19.06%) of COPD HAs were attributable to PM 2.5 and PM 10 exposures on low temperature days, respectively. Our findings suggested that low temperature significantly enhanced the effects of PM and SO₂ on COPD HAs in urban Chengdu, resulting in increased morbidity burden. This evidence has important implications for developing interventions to reduce the risk effect of COPD morbidity., Competing Interests: The authors declare no conflict of interest.

Paeonia qiui is a wild species of tree peony. P. qiui has good ornamental value owing to its leaf color change in spring. So far, the molecular mechanism of leaf color change in P. qiui is unclear. This study analyzes the anthocyanin level and transcriptome of two different color stages in P. qiui leaf. The purplish-red leaf stage is rich in anthocyanin, while the green leaf has very low levels of anthocyanin. Transcriptome analysis reveals that 6678 differentially-expressed genes (DEGs) are up-regulated, and 14,667 are down-regulated in the purplish-red leaf. Among these DEGs, 40 MYB (v-myb avian myeloblastosis viral oncogene homolog) genes, 40 bHLH (MYC-like basic helix-loop-helix) genes, and 15 WD40 (WD-repeat protein) genes were found. Based on phylogenetic and alignment analysis with the deduced amino acid sequences with known transcription factors, Unigene0024459 (MYB1) is likely the R2R3-MYB that promotes anthocyanin biosynthesis; Unigene0050761 (MYB2) is likely the R2R3-MYB that represses anthocyanin biosynthesis; Unigene0005081 (bHLH1) and Unigene0006146 (WD40-1) are likely the bHLH and WD40 that participate in regulating anthocyanin biosynthesis. Additionally, quantitative RT-PCR results confirmed the transcriptome analyses for key genes., Competing Interests: The authors declare no conflict of interest.

Lysophosphatidic acid acyltransferases (LPAATs) are essential for the acylation of lysophosphatidic acid (LPA) and the synthesis of phosphatidic acid (PA), a key intermediate in the synthesis of membrane phospholipids and storage lipids. Here, a putative lysophosphatidic acid acyltransferase gene, designated PrLPAAT4 , was isolated from seed unsaturated fatty acid (UFA)-rich P. rockii . The complete PrLPAAT4 cDNA contained a 1116-bp open reading frame (ORF), encoding a 42.9 kDa protein with 371 amino acid residues. Bioinformatic analysis indicates that PrLPAAT4 is a plasma membrane protein belonging to acyl-CoA:1-acylglycerol-sn-3-phosphate acyltranferases (AGPAT) family. PrLPAAT4 shared high sequence similarity with its homologs from Citrus clementina , Populus trichocarpa , Manihot esculenta , and Ricinus communis . In Arabidopsis, overexpression of PrLPAAT4 resulted in a significant increase in the content of oleic acid (OA) and total fatty acids (FAs) in seeds. AtDGAT1 , AtGPAT9 , and AtOleosin , involved in TAG assembly, were upregulated in PrLPAAT4 -overexpressing lines. These results indicated that PrLPAAT4 functions may be as a positive regulator in seed FA biosynthesis.

Paeonia rockii is a wild tree peony species with large and dark purple variegations at the base of its petals. It is the genetic resource for various variegation patterns in tree peony cultivars, which is in contrast to the pure white petals of Paeonia ostii . However, the molecular mechanism underlying the formation of variegation in this plant is still unknown. Here, we conducted Illumina transcriptome sequencing for P. rockii , P. ostii (with pure white petals) and their F1 individuals (with purple-red variegation). A total of 181,866 unigenes were generated, including a variety of unigenes involved in anthocyanin biosynthesis and sequestration and the regulation of anthocyanin biosynthesis. The dark purple or purple-red variegation patterns mainly occurred due to the proportions of cyanidin (Cy)- and peonidin (Pn)-based anthocyanins. The variegations of P. rockii exhibited a "Cy > Pn" phenotype, whereas the F1 progeny showed a "Pn > Cy" phenotype. The CHS , DFR , ANS , and GST genes might play key roles in variegation pigmentation in P. rockii according to gene expression and interaction network analysis. Two R2R3-MYB transcription factors (c131300.graph&#95;c0 and c133735.graph&#95;c0) regulated variegation formation by controlling CHS , ANS and GST genes. Our results indicated that the various variegation patterns were caused by transcriptional regulation of anthocyanin biosynthesis genes, and the transcription profiles of the R2R3-MYBs provided clues to elucidate the mechanisms underlying this trait. The petal transcriptome data produced in this study will provide a valuable resource for future association investigations of the genetic regulation of various variegation patterns in tree peonies.

Tree peony (Paeonia suffruticosa Andrews) is an important traditional flower in China. Besides its beautiful flower, the leaf of tree peony has also good ornamental value owing to its leaf color change in spring. So far, the molecular mechanism of leaf color change in tree peony is unclear. In this study, the pigment level and transcriptome of three different color stages of tree peony leaf were analyzed. The purplish red leaf was rich in anthocyanin, while yellowish green leaf was rich in chlorophyll and carotenoid. Transcriptome analysis revealed that 4302 differentially expressed genes (DEGs) were upregulated, and 4225 were downregulated in the purplish red leaf vs. yellowish green leaf. Among these DEGs, eight genes were predicted to participate in anthocyanin biosynthesis, eight genes were predicted involved in porphyrin and chlorophyll metabolism, and 10 genes were predicted to participate in carotenoid metabolism. In addition, 27 MYBs, 20 bHLHs, 36 WD40 genes were also identified from DEGs. Anthocyanidin synthase (ANS) is the key gene that controls the anthocyanin level in tree peony leaf. Protochlorophyllide oxido-reductase (POR) is the key gene which regulated the chlorophyll content in tree peony leaf.

Lily (Lilium) is used as an important edible and medical plant species with a vague taxonomic classification and a long history in China. Bulbs of six Lilium species (L. regale, L. concolor, L. pumilum, L. leucanthum, L. davidii var. unicolor and L. lancifolium) native to China were investigated with a view to their exploitation as a potential source of natural antioxidants due to their phenolic composition and dietary antioxidant potential. The results showed that all bulb extracts exhibited strong antioxidant activities, which generally correlated positively with the total phenolic contents (r = 0.68 to 0.94), total flavonoid contents (r = 0.51 to 0.89) and total flavanol contents (r = 0.54 to 0.95). High-performance liquid chromatography (HPLC) analysis revealed that rutin and kaempferol were the major phenolic components in the extracts. Hierarchical cluster analysis showed that L. regale belonged to the group with high phenolic content and strong antioxidant power. L. concolor and L. pumilum were arranged in one group characterized by moderate phenolic content and antioxidant capacity, while L. leucanthum, L. davidii var. unicolor and L. lancifolium were clustered in the third group with low phenolic content and weak antioxidant activity. These strongly suggest that lily bulbs may serve as a potential source of natural antioxidant for food and pharmaceutical applications.