Thuja Research Articles

A time and temperature dependent biosynthesis of silver nanoparticles using the extract of Platycladus orientalis’ fruit

Silver nanoparticles (AgNPs) have gained notable/ huge attention, particularly in the biomedical and antibacterial fields, owing to their distinctive characteristics. Biological synthesis of AgNPs is a prominent method due to its ease of preparation, eco-friendliness, non-toxicity and time efficiency. Herein, AgNPs were synthesized using an extract from "Platycladus orientalis" and their antimicrobial and biological properties were thoroughly investigated. The scaling down of Ag⁺ to Ag⁰ was evident through the appearance of a yellow brownish colour. AgNPs were characterized by UV–Visible spectrum, X-ray diffraction (XRD), and scanning electron microscopy (SEM). UV–Visible spectroscopy revealed absorption peaks at around 440 nm for AgNPs synthesized from fruits’ seat coat of Platycladus orientalis. TEM analysis indicates the average size of AgNPs is approximately 50 nm. Powder XRD confirmed the crystalline nature of the AgNPs, with prominent peaks corresponding to face-centred cubic structures. FTIR analysis identified key functional groups involved in the synthesis process. SEM images displayed agglomerated AgNPs with varying diameters and particle dispersion. Molecular docking results showed favourable binding interactions of AgNPs with the protein 2BTD, with a docking score of -3342 kcal/mol, indicating potential biological activity. These findings highlight the effective synthesis of AgNPs using Platycladus orientalis and their significant potential for biomedical applications.

Comparison of Growth and Metabolomic Profiles of Two Afforestation Cypress Species Cupressus chengiana and Platycladus orientalis Grown at Minjiang Valley in Southwest China.

In recent years, afforestation has been conducted in China's hot and dry valleys. However, there is still a paucity of knowledge regarding the performance of tree species in these semi-arid regions, particularly with regard to interspecies differences. The present study compares the growth and metabolome characteristics of two widely used cypress species, namely Cupressus chengiana and Platycladus orientalis, grown at two sites with distinct climate conditions in the hot and dry Minjiang Valley in southwestern China. The findings indicate that C. chengiana trees exhibit superior growth rates compared to P. orientalis trees at both study sites. In comparison to P. orientalis trees, C. chengiana trees demonstrated a greater tendency to close their stomata in order to prevent water loss at the hotter and drier site, Llianghekou (LHK). Additionally, C. chengiana trees exhibited significantly lower hydrogen peroxide levels than P. orientalis trees, either due to lower production and/or higher scavenging of reactive oxygen species. C. chengiana trees accumulated soluble sugars as well as sugar derivatives, particularly those involved in sucrose and galactose metabolisms under stressful conditions. The species-specific differences were also reflected in metabolites involved in the tricarboxylic acid cycle, nitrogen, and secondary metabolisms. The metabolome profiles of the two species appeared to be influenced by the prevailing climatic conditions. It appeared that the trees at the drier and hotter site, LHK, were capable of efficient nitrogen uptake from the soil despite the low soil nitrogen concentration. This study is the first to compare the growth performance and metabolic profiles of two widely used tree species with high resistance to adverse conditions. In addition to the species-specific differences and adaptations to different sites, the present study also provides insights into potential management strategies to alleviate abiotic stress, particularly with regard to nitrogen nutrients, in the context of climate change.

Hinokiflavone exerts dual regulation on apoptosis and pyroptosis via the SIX4/Stat3/Akt pathway to alleviate APAP-induced liver injury

Hinokiflavone (HF), classified as a flavonoid, is a main bioactive compound in Platycladus orientalis and Selaginella. HF exhibits activities including anti-HIV, anti-inflammatory, antiviral, antioxidant and anti-tumor effects. The study aimed to explore the function and the mechanisms of HF on acetaminophen (APAP)-induced acute liver injury. Results indicated that HF treatment mitigated the impact of APAP on viability and restored levels of MDA, GSH and SOD on HepG2 cells. The accumulation of reactive oxygen species (ROS) mitochondrial membrane potential (MMP) in HepG2 cells stimulated by APAP were also blocked by HF. HF reduced the levels of pro-apoptotic and pro-pyroptotic proteins. Flow cytometry analysis and fluorescence staining results were consistent with western blot analysis. Following HF treatment in the APAP-induced cell model, there was observed an augmentation in the phosphorylation of Stat3 and an increase in the expression of SIX4. However, not only silenced the SIX4 protein in HepG2 cells by siRNA, but also adding the Stat3 inhibitor (Stattic), attenuated the anti-apoptotic and anti-pyroptotic effects of HF significantly. Furthermore, HF alleviated liver damage in C57BL/6 mice model. Overall, our study demonstrated that HF mitigates apoptosis and pyroptosis induced by APAP in drug-induced liver injury (DILI) through the SIX4/Akt/Stat3 pathway in vivo and in vitro. HF may have promising potential for for the treatment of DILI.

Chemometrics of the composition and antioxidant capacity of essential oils obtained from six Cupressaceae taxa

Essential oils (EOs) are complex and susceptible to environmental conditions, they have a wide range of biological activities and are often used to differentiate between similar species. In this study, gas chromatography-mass spectrometry (GC–MS) coupled with chemometric analysis was applied to systematically analyse and evaluate EOs constituents and antioxidant activity of six Chinese Cupressaceae taxa (Platycladus orientalis Franco, P. orientalis Franco ‘Sieboldii’, P. orientalis Franco ‘Aurea’, Juniperus chinensis Roxb., J. chinensis Roxb. ‘Kaizuca’, and J. sabina L.) under identical conditions. The antioxidant activity of the EOs was evaluated using 2,2 -diphenyl-1-picrylhydrazyl (DPPH), 2,2’-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), and ferric reducing power (FRAP), and the total phenolic content (TPC) of the EOs was determined by Folin–Ciocalteau reagent. In total, seventy individual constituents were identified with the main components being α-pinene, sabinene, d-limonene, bornyl acetate, δ-3-carene and β-myrcene. Principal component analysis (PCA) and hierarchal cluster analysis (HCA) successfully discriminated the six taxa into three chemotypes and the unique chemotype revealed that J. chinensis ‘Kaizuca’ may be a species rather than a cultivar of J. chinensis. The results of OPLS-DA analysis showed that the three compounds screened, namely, α-pinene, sabinene, and δ-3-carene, can completely distinguish Platycladus spp. from Juniperus spp. The DPPH assay results ranged from 576.14 (J. chinensis ‘Kaizuca’) to 1146.12 (J. sabina) μmol eq Trolox/mL EO, while the ABTS values ranged from 1579.62 (P. orientalis ‘Aurea’) to 5071.82 (J. sabina) μmol eq Trolox/mL. In the FRAP assay, the values ranged from 1086.50 (J. chinensis ‘Kaizuca’) to 1191.18 (J. sabina) μmol eq Trolox/ml and the TPC of the EOs studied ranged from 15.17 (J. chinensis ‘Kaizuca’) to 39.37 (J. sabina) mg GAE/mL EO. The results consistently showed that J. sabina possessed the strongest antioxidant activity and can be preferentially used as a rich source of potentially natural antioxidants.

An ultraviolet radiation protective transparent wood film retained natural wood texture and tactile properties

In this study, the raw material of Japanese cypress wood (Platycladus orientalis (Linn.) Franco) was used and subjected to a series of treatment, including replacement of the water in wood by organic solvent, liquid UV-curable coating impregnation, surface coating removal, and UV curing. By this method, we innovatively produced a new type of transparent wood film which we refer to as “wood-texture transparent wood” (WTTW). WTTW retained the color, texture, and tactility of wood, while exhibiting a high transmittance of light and haze. Macroscopic and microscopic tests demonstrated that by removing the excess coating on the impregnated wood film surface, the microstructure and roughness of the wood surface could be successfully preserved, and the wood-like tactility of WTTW could be realized. WTTW exhibits better properties than those of the original wood, including a maximum light transmittance of 72.3 %, a haze of 72.3 % (at 550 nm), a tensile strength of 123.90 MPa in the longitudinal direction, a tensile strength of 6.64 MPa in the cross direction, and a hardness of 81.8 HD. In comparison to the traditional transparent wood, WTTW not only streamlines the preparation process, but also preserves the original wood texture, which aligns more closely with the tenets of green environmental protection and is more suitable for home decoration and privacy protection.

Ethanolic Extracts of Cupressaceae Species Conifers Provide Rapid Protection against Barium Chloride-Induced Cardiac Arrhythmia.

Sudden cardiac death (SCD) is responsible for a high percentage of cardiovascular fatalities, with ventricular arrhythmias being the most common cause. Despite numerous clinically available antiarrhythmic drugs (AADs), AADs retain some undesirable arrhythmic effects, and their inappropriate use can lead to severe adverse reactions. The exploration of new therapeutic options against arrhythmias with fewer unreceptive effects is of utmost importance. The ethanolic extracts of seven Cupressaceae species, namely, Chamaecyparis obtusa, Juniperus chinensis (L.) Ant., Sabina chinensis (L.) Ant. cv. Kaizuca, Platycladus orientalis (L.) Franco, Juniperus sabina L., Fokienia hodginsii, and Juniperus chinensis 'Pyramidalis' were investigated for their pharmacological effects on barium chloride (BaCl2)-induced arrhythmia using normal II lead electrocardiogram (ECG) measurements in a mouse model. According to the ECG profiles, pretreatment with C. obtusa, P. orientalis, and J. sabina extracts provoked dose-dependent protection against BaCl2-induced arrhythmia, while pretreatment with the other four species and amiodarone did not exert cardioprotective effects. The treatment effects were confirmed using a rat model. The therapeutic effects of C. obtusa, P. orientalis, and J. sabina extracts on the M2 and M3 receptors but not the M1 receptor were mediated by the inhibition of the M2 receptor blocker (methoctramine tetrahydrochloride), M3 antagonist (4-DAMP), or M1 receptor blocker (pirenzepine dihydrochloride). This first-line evidence illustrates that certain Cupressaceae species possess active antiarrhythmic components. The first line of key findings revealed that active components of certain Cupressaceae species have cardioprotective effects, suggesting that these innovative phytochemicals have promising potential for preventing the occurrence of cardiac arrhythmia and reducing sudden cardiac death.

Tree-Ring δ13C and Intrinsic Water-Use Efficiency Reveal Physiological Responses to Climate Change in Semi-Arid Areas of North China

Climate change has had a widespread and profound impact on global temperature and precipitation patterns, especially in semi-arid areas. Plant δ13C and iWUE indicate the trade-off between carbon uptake and water loss, which is pivotal for understanding plant responses to climate change. Information about the long-term responses of the physiological and ecological processes of different tree species to climate change is also required. To investigate the impact of different forest stand structures and site conditions on long-term growth and physiological processes of coniferous and broad-leaved trees in the mountainous area of Beijing, we analyzed the tree-ring δ13C variation of four tree species (Platycladus orientalis, Pinus tabuliformis, Quercus variabilis, Robinia pseudoacacia) sampled from 64 plots with varying site and stand conditions. We found that the tree-ring δ13C of the four tree species varied from each other and was mainly affected by density and slope aspect, followed by slope and age. Both tree-ring δ13C and iWUE of the four tree species showed increasing trends over time, mechanistically linked to long-term changes in global CO2 concentration. This indicates the four native tree species have adapted well to climate change, and the risk of decline is relatively low. The increased iWUE translated into different growth patterns which varied with tree species, site, and stand condition. Different tree species have varying sensitivities to environmental factors. The iWUE of coniferous tree species is more sensitive to climate change than that of broad-leaved tree species, especially to temperature (T), the Standardized Precipitation Evapotranspiration Index (SPEI), and vapor pressure deficit (VPD).

Peningkatan Literasi Biodiversitas Menggunakan Model Kebun Botani di Madiun

The improvement of literacy on biodiversity growing in the residential areas can support the attitude of society to sustain the ecology, even improving the life quality based on local potentials. However, there are limited live-learning facilities available for biodiversity education. Hence, a community service was carried out by the Study Program of Biology and Study Program of Food Technology, Faculty of Agricultural Technology, Widya Mandala Surabaya Catholic University, Indonesia. Its objective was to improve literacy on biodiversity of the societal partners through knowledge enrichment and awareness of biodiversification potentials which grow in their residential areas. The societal partners are alumni, high school students (St. Bonaventura and the 6th State High School, Madiun), and Pemberdayaan Kesejahteraan Keluarga (PKK) group “Asman Toga” from Rejomulyo village, Madiun; totally 45 participants. The activities included (a) building a botanical garden named Arbor Vitae”, (b)focused group discussion (FGD), and (c) workshop. Currently, it finished a clearing land and planting more than 50 species for foods and nutraceutical/medicinal sources as well as ecological services. The “Arbor Vitae” had been embedded into university institution by appointing a management in charged. Meanwhile, the improvement of literacy was measured from pre- and post-test during FGD which indicated a significant increase in partners’ literacy by 45.44%; after screening 18 respondents completely filled the tests. The test statements grouped into four indicators of literacy on biodiversity. Moreover, the workshop was complementarily improving the partners’ skill with technology of telang flower jelly drink, purslane medical simplisia, and water clarification using moringa seeds.

Full-Length Transcriptome Assembly of Platycladus orientalis Root Integrated with RNA-Seq to Identify Genes in Response to Root Pruning

Platycladus orientalis (P. orientalis) is a common tree used for vegetation restoration in northern China, and its large area propagation helps to improve site conditions. However, under harsh conditions such as poor land, the survival rate of P. orientalis is very low. Numerous studies have shown that root pruning can promote the formation of lateral roots in seedlings, enhancing the roots’ capacity to absorb soil nutrients and water, and thereby improving the survival rate of seedlings. In this study, a one-third root pruning treatment was applied to P. orientalis seedlings, and the whole transcriptome of seedlings subjected to both control (CK) and root pruning treatments was sequenced to analyze their gene expression profiles. This study investigated the regulatory mechanisms of lateral root development in response to root pruning damage at the molecular level. Using nine cells, 15.28 Gb of clean data were obtained, which yielded 101,688 high-quality full-length transcript sequences and 22,955 low-quality full-length transcript sequences after clustering. Redundancy was then removed using CD-HIT, and Illumina RNA-seq sequencing produced 139.26 Gb of clean data. A total of 2025 differentially expressed genes (DEGs) were identified at three time points following root pruning treatment. Enrichment analysis revealed that the peroxidase gene family plays a significant role in lateral root proliferation. Furthermore, the expression levels of the peroxidase gene family were notably upregulated in comparison to the control group. Pathway enrichment analysis identified 22 relevant genes, which appeared to be highly associated with root growth and resilience to stress. Through examining the expression patterns and correlations of these genes, five central genes emerged as key players. The findings of this research suggest that the peroxidase gene family plays a crucial role in the stress response and root development of P. orientalis, providing reference and guidance for root development in other plant species.

Plant species composition and key‐species abundance drive ecosystem multifunctionality

Abstract Global biodiversity loss has generated great interest in the role of plant communities in driving ecosystem functions. There is limited understanding of how soil properties, plant richness and plant community composition interact to affect ecosystem multifunctionality. We conducted a constructed ecosystem experiment by simultaneously manipulating soil origin (i.e. fertile farmland soil and relatively infertile bare land soil), plant richness and community composition (one‐species monoculture, and all possible two‐, three‐ and four‐species combinations of five plants) to evaluate their influence on ecosystem multifunctionality related to the accumulation of biomass, carbon (C) and nitrogen (N) in plants, greenhouse gas emissions, soil nutrients, soil N fixation and mineralization of N and phosphorus (P). We found that ecosystem multifunctionality was significantly affected by soil origin, plant community composition and the community‐weighted mean (CWM) of plant biomass, but not by plant richness. We grouped the community composition into the N‐fixing group (including N‐fixing plants) and the non‐N‐fixing group (excluding N‐fixing plants). The N‐fixing plant group exhibited significantly higher multifunctionality than the non‐N‐fixing species group in both soil origins. For bare land soil, multifunctionality increased with the increasing relative abundance and biomass ratio of Albizia julibrissin (N‐fixing species) in communities, but decreased with the biomass ratio of Platycladus orientalis (non‐N‐fixing species). For farmland soil, multifunctionality increased with the abundance of Toona sinensis (non‐N‐fixing species) and the biomass ratio of Albizia julibrissin, but decreased with the abundance and biomass ratio of Morus alba (non‐N‐fixing species). These results indicate that the key species determining ecosystem multifunctionality vary under different soil conditions. Synthesis and applications: We propose that plant community composition and the relative abundance and biomass ratio of key species drive ecosystem multifunctionality. We suggest that selecting the appropriate plant combination under different soil conditions should be emphasized in ecological restoration projects. Our study highlights the differentiated roles of key species on ecosystem functions under different resource conditions. The N fixation in general plays a crucial role in driving ecosystem multifunctionality and the N‐fixing plants can serve as restoration tools in nutrient‐poor degraded lands.

Analysis of the stakes of the Xianyang Ancient Ferry Site, Shaanxi, China

Historical records indicate that Xianyang Ancient Ferry Site, dating back over three millennia to the late Shang Dynasty, has been an important transportation hub in ancient times. The use of combined wooden stakes and stones is a special method for flood control among ancient flood prevention techniques. This research aims to evaluate the current preservation condition of these ancient wooden stakes. The dating of the wooden stakes at the site ranges between 940 ± 30 BP and 320 ± 30 BP. The fiber cross-section and microstructure images of the wooden samples indicate that the wood is attributed to Platycladus orientalis. SEM images indicate decay and deterioration of the wooden samples, with the presence of mold spores within the cavities. XRD, FTIR, and TG/DSC spectra of historical wooden samples collected from the site and fresh Platycladus orientalis wood samples demonstrate a significant decrease of cellulose crystallinity in the historical samples, leading to severe deterioration of the wood at the site. Five dominant mold species were identified, i.e., Aspergillus niger, Aspergillus flavus, Penicillium citrinum, Trichoderma, and Phanerochaete chrysosporium, which accelerate the degradation of cellulose and other polysaccharides. This research provides scientific evidence for the selection of reinforcement materials and guides curators and conservators to formulate conservation strategies in the future.

Antioxidant Properties of Platycladus orientalis Flavonoids for Treating UV-Induced Damage in Androgenetic Alopecia Hair.

Androgenetic alopecia (AGA) causes thinning hair, but poor hair quality in balding areas and damage from UV radiation have been overlooked. Plant extracts like Platycladus orientalis flavonoids (POFs) may improve hair quality in AGA. This study examines POFs' effectiveness in treating AGA-affected hair and repairing UV-induced damage. Hair samples were analyzed using scanning electron microscopy (SEM) to examine surface characteristics, electron paramagnetic resonance (EPR) spectroscopy to measure free radicals in the hair, and spectrophotometry to assess changes in hair properties. POFs effectively removed hydroxyl radicals from keratinocytes and had antioxidant properties. They also reduced UV-induced damage to AGA hair by mitigating the production of melanin free radicals. Following POF treatment, the reduction in peroxidized lipid loss in AGA hair was notable at 59.72%, thereby effectively delaying the progression of hair color change. Moreover, protein loss decreased by 191.1 μ/g and tryptophan loss by 15.03%, ultimately enhancing hair's tensile strength. compared to healthy hair, hair damaged by AGA shows more pronounced signs of damage when exposed to UV radiation. POFs help protect balding hair by reducing oxidative damage and slowing down melanin degradation.

Understorey Plant Functional Traits of Platycladus orientalis Depends on Crown Closure and Soil Properties in the Loess Plateau, China

The crown closure of Platycladus orientalis forests has a wide-ranging impact on vegetation and soil, thereby affecting the overall functioning of the ecosystem. There is limited research on the effects of the Platycladus orientalis forest crown closure on changes in community plant functional traits, and their interactions are not yet clear. Therefore, we investigated 50 plots of different types of Platycladus orientalis crown closure, and we measured the functional traits of nine shrub species and 68 herb species in 50 plots under five different densities of Platycladus orientalis forests in the Loess Plateau. The consequence of Pearson’s correlation analysis showed significant positive correlations between LC and LTD, LN and LP, LN and LNP, LN and LV, LN and H, LP and LV, LP and H, and SLA and LV (p < 0.05). LC was significantly negatively correlated with LP, LC with SLA, LC with LV, LN with LTD, LP with LNP, LP with LTD, and LTD with H (p < 0.05). Only the soil phosphorus content (SP) and soil water content (SWC) showed a significant positive correlation with multiple plant functional traits. The crown closure of Platycladus orientalis forests increased significantly, as did the plant functional features. Changes in the Platycladus orientalis forest crown closure significantly increased the LC, LV, LN, LP, and SLA in plant functional traits. An increase in Platycladus orientalis forest crown closure significantly increased the soil organic carbon (SC), soil phosphorus content (SP), soil nitrogen content (SN), soil water content (SWC), field capacity (FC), and soil porosity (PO). Based on a structural equation model, we found that, while changes in the Platycladus orientalis forest crown closure did not directly affect plant functional traits, they could indirectly influence these traits through soil factors, primarily the soil water content (SWC) and soil phosphorus content (SP) (p < 0.05). Additionally, the mechanisms of the Platycladus orientalis forest crown closure’s impact on different functional traits vary. The research results provide scientific elements for the ecological restoration of Platycladus orientalis forests on the Loess Plateau.

Hazardous waste management of novel non-edible Platycladus orientalis seed oil via recyclable yttria-based phyto-nanocatalyst: A practical approach towards sustainable bioenergy conversion

In current scenario of rising issues of economic crises, ecotoxicity and waste management, the search of novel, waste and non-food biomass for green energy production has become indispensable. This study is concerned with Platycladus orientalis, a novel feedstock with a seed oil concentration of 28 % (w/w), optimized via simulation-based response surface methodology (RSM) for biodiesel production. To enhance catalytic activity during transesterification, novel Yttria-based green metallic oxide, a phyto-nanocatalyst, was synthesized using Platycladus orientalis dried seed cones aqueous extract. The Yttria-based phytonanocatalyst was characterized using FTIR, XRD, SEM, and EDX that confirmed its structural and elemental composition with 12 nm nano-size and demonstrated the high catalytic efficiency. The optimal conditions for biodiesel synthesis were identified as methanol-to-oil ratio (7:1), catalyst concentration (0.14 wt%), reaction time (105 min), and reaction temperature (80 °C) with remarkable biodiesel yield (96 %). The reusability of the Yttria-based green nanoparticles was assessed over six reaction cycles. Methyl ester formation was validated through FTIR, GC–MS, and NMR analyses. The fuel properties were found to fall within the range recommended by the international biodiesel standards i.e. flash point of 90 °C, density of 0.614 kg/L, viscosity of 4.21 cSt, pour point of −8 °C, cloud point of −10 °C, total acid number of 0.124 mg KOH/g and sulfur content of 0.00002 wt%. With its prolific seed production and wide distribution, Platycladus orientalis is a highly recommendable species for sustainable and eco-friendly biodiesel production. This study contributes to the evolving field of green catalysis, offering a viable solution to environmental issues and waste management challenges in the biodiesel industry.

Divergent effects of single and combined stress of drought and salinity on the physiological traits and soil properties of Platycladus orientalis saplings.

Drought and salinity are two abiotic stresses that affect plant productivity. We exposed 2-year-old Platycladus orientalis saplings to single and combined stress of drought and salinity. Subsequently, the responses of physiological traits and soil properties were investigated. Biochemical traits such as leaf and root phytohormone content significantly increased under most stress conditions. Single drought stress resulted in significantly decreased nonstructural carbohydrate (NSC) content in stems and roots, while single salt stress and combined stress resulted in diverse response of NSC content. Xylem water potential of P. orientalis decreased significantly under both single drought and single salt stress, as well as the combined stress. Under the combined stress of drought and severe salt, xylem hydraulic conductivity significantly decreased while NSC content was unaffected, demonstrating that the risk of xylem hydraulic failure may be greater than carbon starvation. The tracheid lumen diameter and the tracheid double wall thickness of root and stem xylem was hardly affected by any stress, except for the stem tracheid lumen diameter, which was significantly increased under the combined stress. Soil ammonium nitrogen, nitrate nitrogen and available potassium content was only significantly affected by single salt stress, while soil available phosphorus content was not affected by any stress. Single drought stress had a stronger effect on the alpha diversity of rhizobacteria communities, and single salt stress had a stronger effect on soil nutrient availability, while combined stress showed relatively limited effect on these soil properties. Regarding physiological traits, responses of P. orientalis saplings under single and combined stress of drought and salt were diverse, and effects of combined stress could not be directly extrapolated from any single stress. Compared to single stress, the effect of combined stress on phytohormone content and hydraulic traits was negative to P. orientalis saplings, while the combined stress offset the negative effects of single drought stress on NSC content. Our study provided more comprehensive information on the response of the physiological traits and soil properties of P. orientalis saplings under single and combined stress of drought and salt, which would be helpful to understand the adapting mechanism of woody plants to abiotic stress.

Estimating and simulating dust absorption ability by Eldar pine, Oriental Arbor-vitae, River red gum and European Olive

Estimating and simulating dust absorption ability by Eldar pine, Oriental Arbor-vitae, River red gum and European Olive

Tree root-mediated soil metabolome in agroforestry enhancing the growth and quality of Panax notoginseng

Abstract Purpose The ecological cultivation of Panax notoginseng under a forest canopy relies on the coupling of the P. notoginseng growth environment and the forest ecosystem Methods In this study, six tree species, such as Platycladus orientalis (L.) Franco, were chosen to research the effects of species interactions on the growth, quality, and disease occurrence under intercropping with P. notoginseng, with single P. notoginseng serving as the control. Results Intercropping P. notoginseng with PO (Platycladus orientalis, a coniferous tree species) or with SW (Schima wallichii Choisy, a broad-leaved tree species) promoted the accumulation of P. notoginseng biomass, reduced the occurrence of root rot, improved the contents of nitrogen, phosphorus and potassium in P. notoginseng, and increased the saponin concentration. Then, 43 differentially abundant metabolites were screened in the P. notoginseng-tree intercropping system by soil metabolism analysis and compared with those in the monocropped system. Indole-3-carboxaldehyde showed a significant negative relationship with the occurrence of root rot disease and inhibited Fusarium oxysporum. In addition, 2-naphthalenesulfonic acid was significantly positively correlated with biomass and increased the dry weight in the underground part of P. notoginseng in the pot experiments. Conclusions Thus, the coniferous tree species PO and the broad-leaved tree species SW are potentially good neighbours of P. notoginseng, and soil metabolic changes may be important mechanisms for the growth and disease resistance benefits observed in the understorey of P. notoginseng.

Elevation Shapes Soil Microbial Diversity and Carbon Cycling in Platycladus orientalis Plantations

Diversified soil microbiomes are the key drivers of carbon fixation and plant residue decomposition in forest ecosystems. Revealing the elevation patterns of soil microbial carbon cycling in forests is essential for utilization of forest ecological resources. However, the soil microbial diversity and carbon cycle processes in Platycladus orientalis plantations across different elevations are still unclear. Here, we established a gradient with three elevations (118 m, 300 m, and 505 m) on the Beijing Ming Dynasty Tombs Forest Farm, which is located in Changping District, Beijing. The metagenomics method was applied to study the soil microbiome, with a special focus on the carbon cycle process at each elevation. We found the diversity and composition of the soil microbiomes significantly varied across the elevation gradients. The structure of bacteria and archaea was mainly driven by soil total potassium, pH and NH4+, but the eukaryota had no significant relationship with the environmental factors. The relative abundance of genes involved in microbial carbon fixation and decomposition of organic carbon were also significantly impacted by elevation, with the former showing increasing, u-shaped, or hump trends with increasing elevation, but the latter only showing hump trends. The rTCA cycle and 3-hydroxypropionate pathway were the dominant carbon fixation pathways in the Platycladus orientalis plantations. The elevation gradient shaped the microbial decomposition of plant-derived organic carbon by changing soil properties and, furthermore, led to soil organic carbon stock losses. These findings increase our understanding of soil microbial diversity and the carbon cycle across different elevations and provide a theoretical basis for the utilization of forest ecological resources to promote carbon sequestration.

Assessment of the Allergenic Potential of Urban Woody Flora of Rostov-on-Don

Introduction. Plant pollen causes various allergic reactions in humans, including respiratory diseases, immune system disorders, bronchitis, conjunctivitis, dermatitis, and hay fever. These diseases affect up to 30% of the world's population. In large cities, trees and shrubs used in landscaping are significant sources of allergenic dust. Despite this, the greening of cities worldwide often occurs without considering the allergenic properties of plants. With the development of proteomics, it has become possible to assess the degree of allergenicity of proteins that make up plant pollen in detail. Based on this information, a scale of potential allergenicity for woody plants has been developed. The aim of this study is to assess the allergenic potential of woody plants in the urban flora of Rostov-on-Don.Materials and Methods. The object of the study was trees and shrubs used in the landscaping of Rostov-on-Don. The analysis of floristic data was based on the materials obtained during field work in 2023 on the territory of Rostov-on-Don. The author also used the lists of the city's dendroflora compiled between 2007 and 2022. The assessment of the potential allergenicity of woody plant species was conducted on a five-point scale, with 0 indicating plants that did not pose an allergic hazard, 1 indicating a low allergenicity level, 2 indicating a medium class, 3 indicating a high level, and 4 indicating a very high level of allergenicity.Results. In the flora of woody plants in Rostov-on-Don, 61 species of potentially allergenic plants were identified, posing varying levels of danger to human health. The share of all types of potentially allergenic woody plants was 30% of the total number of urban woody flora species in the city. The most powerful sources of allergenic pollen included nine species (Fraxinus Excelsior, Betula Pendula, B. Verrucosa, Platycladus Orientalis, etc.), which posed the greatest threat of hay fever and other allergic reactions. As a rule, these were typically wind-pollinated plants that produced maximum amounts of pollen. The list of potentially allergenic species included a significant number of adventitious species (24 species), which made it difficult to control their spread. A taxonomic analysis of potentially allergenic species was carried out at the order level, for which specific protein reactions were identified and detailed approaches to the prevention and treatment of hay fever were developed. The orders Pinales and Fagales form the bulk of allergenic pollen in the winter-spring period.Discussion and Conclusion. For the first time, studies were conducted on the allergenic activity of urban woody flora in the southern regions of Russia. An assessment of their allergenic potential allowed us to determine the level of threat of allergic reactions in humans. The greatest danger comes from both allergenic and invasive species that can spread actively and increase in numbers. Representatives of the Pinales and Fagales orders have proven to be significant sources of allergenic pollen, as they often have high ornamental qualities and play a prominent role in design projects. In some cases, it may be possible to replace these cultures with less allergenic alternatives, such as representatives of the Rosales order, to reduce the risk of allergic reactions.

Climate drivers of litterfall biomass dynamics in three types of forest stands on the Loess Plateau

Litterfall is a link in the energy flow and material cycling of ecosystems, which maintain the primary productivity of forests. However, there is no consensus regarding the factors driving for the litterfall biomass dynamics because of the high spatial–temporal heterogeneity. Herein, we investigated and compared the stand litter biomass, litterfall biomass, including its components in the pure Robinia pseudoacacia forest (RL), pure Platycladus orientalis forest (PL), and mixed forest of Robinia pseudoacacia and Platycladus orientalis (ML) from 2020 to 2022 in the gully erosion area of the Loess Plateau. Correlation and multiple regression analyses were used to study the relationships among the amount of stand litter, litterfall biomass, and seasonal temperature and precipitation. Significant variation was found in the seasonal and annual litterfall biomass of the three types of forest stands. Annual stand litter biomass was in the order PL > RL > ML, whereas the annual litterfall biomass was in the order RL > ML > PL. The seasonal dynamics of litterfall biomass of twigs, leaf and fruits exhibited a ‘unimodal pattern’ with a peak in October. Annual leaf litterfall biomass formed, the main body of litter in all the components, accounting for 57.14–67.05 % of the total litterfall biomass. The correlation and regression analysis results showed that the stand litter biomass was primarily affected by the average temperature. Total litterfall biomass and twigs, leaf, and fruits were significantly affected by the precipitation and the maximum temperature, however, flower litterfall biomass was mainly affected by the average temperature. Overall, our results indicated that temperature plays a key role in the climatic factors affecting forest litterfall processes, while different climatic conditions and biological characteristics probably caused the differences in litterfall biomass. In the long term, temperature will potentially play a leading role in altering carbon storage and nutrient cycling as the climate warms.