Pinus Densiflora Research Articles

Pinus densiflora Root Extract Attenuates Osteoarthritis Progression by Inhibiting Inflammation and Cartilage Degradation in Interleukin-1β and Monosodium Iodoacetate-Induced Osteoarthritis Models.

Osteoarthritis (OA) is a common degenerative joint condition caused by an imbalance between cartilage synthesis and degradation, which disrupts joint homeostasis. This study investigated the anti-inflammatory and joint-improving effects of Pinus densiflora root extract powder (PDREP) in both in vitro and in vivo OA models. In an in vitro OA model, in which SW1353 human chondrosarcoma cells were treated with interleukin (IL)-1β, PDREP treatment significantly reduced the mRNA levels of matrix metalloproteinase (MMP)-1, MMP-3, and MMP-13 while enhancing collagen type II alpha 1 (Col2a1) mRNA level, and decreased IL-6 and prostaglandin E2 (PGE2) levels. In addition, PDREP inhibited the phosphorylation of extracellular signal-regulated kinases (ERK), c-Jun N-terminal kinase (JNK), p38, nuclear factor-kappa B (NF-κB), and the expression of inducible nitric oxide synthase (iNOS). In a monosodium iodoacetate (MIA)-induced OA rat model, the administration of PDREP resulted in decreased OA clinical indices, improved weight-bearing indices and gait patterns, reduced histological damage, and lowered serum inflammatory cytokine and MMPs expression. Furthermore, PDREP downregulated the phosphorylation of ERK, JNK, p38, and NF-κB, as well as the expression of iNOS, consistent with the in vitro findings. These results suggest that PDREP exhibits anti-inflammatory and joint-improving effects and has potential as a therapeutic strategy or functional food for the treatment of OA.

Fundamental natural frequency and floor impact sound insulation performance of CLT slabs based on wood species and panel connections: An experimental study

The effects of wood species and panel connections on the vibration and heavy-weight impact sound insulation performance of cross-laminated timber (CLT) slabs were investigated. CLT panels (5-ply, 150 mm thick, 1 m wide, and 4.2 m long) made of larch (Larix kaempferi) and pine (Pinus densiflora) were manufactured with 30 mm thick laminae, considering three types of joints. Three CLT panels of the same species and joint type were connected using spline joints, butt joints, or half-lap joints to form 3 m wide and 4.2 m long slabs for testing. The floor impact sound insulation performance of the CLT slabs was measured according to KS F ISO 10140-3, using the standard heavy-weight impact source, a rubber ball. Additionally, four accelerometers were installed at 400 mm intervals beneath the CLT slabs to analyze the deflections and natural frequencies of the slabs. The results of the experiment indicated that there were no significant differences depending on the wood species and the CLT panel joints. These findings suggest that wood species and joint methods can be flexibly applied in the design of CLT slabs.

Enhanced Resistance to Pinewood Nematode Disease in Pinus densiflora Induced by Fungal Elicitor from Penicillium chrysogenum

Pine wilt disease, caused by the pine wood nematode (Bursaphelenchus xylophilus), poses a serious threat to forests in Korea. In this study, we investigated the resistance of Pinus densiflora to B. xylophilus following treatment with a fungal elicitor derived from Penicillium chrysogenum through trunk injection and soil drenching. Soil drenching with the fungal elicitor led to increased accumulation of two key defensive compounds: pinosylvin monomethyl ether (PME) and dihydropinosylvin monomethyl ether (DPME) in the needles. In untreated control plants inoculated with B. xylophilus, 67.9% died within five months, whereas only 33.3% of plants pretreated with the elicitor succumbed. Trunk injection of the fungal elicitor also significantly enhanced PME production. The PME concentration in the needles peaked at 155.4 µg/g dry weight (DW) four weeks post-elicitor injection. To assess the impact of elicitor treatment on nematode resistance, we monitored the downward movement of B. xylophilus in plants two months post-injection of fungal elicitor. Nematodes were introduced at the upper internodal segments of branches, and their mobility to the lower segments was measured. In elicitor-treated trees, the movement and population of B. xylophilus were significantly reduced, highlighting the effectiveness of the treatment. These results demonstrate that fungal elicitor treatments, through soil drenching or trunk injection, can enhance the resistance of P. densiflora to B. xylophilus. This eco-friendly approach offers a promising strategy for managing pine wilt disease in susceptible pine species.

Pinus densiflora var. ussuriensis Forest Alliance

The Pinus densiflora var. ussuriensis forest is a unique pine forest type in Northeast China. The species grows normally under extremely adverse conditions because it has a strong tolerance to poor soils and drought. It also benefits the ecological environment significantly through water conservation, soil improvement and windbreak and sand fixation, thus making it an important pioneer species for improving site conditions. This paper systematically analyzes the geographical distribution, ecological and community characteristics, species composition and classification of Pinus densiflora var. ussuriensis forests in China through field surveys and literature review. The main findings are: (1) Based on the dominant species of each layer, Pinus densiflora var. ussuriensis forests can be divided into two categories of associations: Pinus densiflora var. ussuriensis - Rhododendron dauricum - Carex callitrichos association and Pinus densiflora var. ussuriensis + Quercus mongolica - Lespedeza bicolor - Carex caespitosa association. (2) According to sample plot surveys, a total of 134 vascular plant species, belonging to 59 families and 104 genera, were recorded in natural Pinus densiflora var. ussuriensis forests. Amongst them were one fern species, two gymnosperm species and 131 angiosperm species. (3) The composition of life forms in Pinus densiflora var. ussuriensis forests is dominated by terrestrial herbs, with fewer woody plants and with vines making up the smallest proportion. (4) The Pinus densiflora var. ussuriensis forests located on the hillocks of Xingkai Lake are in decline. If the soil in this area continues to increase in wetness, this community may eventually evolve into a broad-leaved mixed forest.

Changes in Soil Physicochemical Properties and Fungal Communities Following a Forest Fire in the Pine Forest of Uljin, Republic of Korea

Soil samples from the rhizosphere of pine (Pinus densiflora) stands in the fire-disturbed Uljin forest were collected to analyze their physicochemical properties and fungal communities. In the burned area, soil pH decreased by 0.56, and organic matter content decreased by 0.32%p compared to the undisturbed area. Fungal community analysis revealed that all alpha diversity indices decreased in the burned area, but there were no differences according to fire severity. Soil pH, available phosphorus, and total nitrogen showed a positive correlation with the alpha diversity. Additionally, beta diversity analysis also indicated significant differences in the fungal communities between the burned area and the control sites (p value = 0.031). The changes in fungal communities were considered to be influenced by the decline in the order Atheliales, genus Russula, and genus Trechispora. A prediction analysis of the functional traits of fungi showed that the number of fungi involved in nutrient absorption and decomposition decreased in the burned area. It seems that the soil restoration of pine forests is progressing very slowly, as the soil fungi related to nutrient absorption by pine trees have not recovered even 18 months after the forest fire. Therefore, it is necessary to monitor continuous fungal communities in pine forest restoration after a forest fire to determine forest ecosystem restoration success and stabilization.

Eco-friendly biocontrol of pine wilt disease: Enhancing tree defense with Bacillus subtilis JCK-1398 for sustainable forest management

Pine wilt disease (PWD), caused by pinewood nematodes (Bursaphelenchus xylophilus), poses a significant threat to forestry worldwide. This study introduces a novel biocontrol strategy using Bacillus subtilis JCK-1398, which was selected and identified for its resistance-induction potential after extensive screening of microbial strains from pine tissues. The bacterium was found to biostimulate resistance in Pinus densiflora. Comprehensive analyses, including transcriptomics, qPCR assays, and high-performance liquid chromatography (HPLC), revealed that B. subtilis JCK-1398 significantly upregulates defense-related genes and stimulates pinoresinol production, a compound linked to resistance against nematodes. Treatment with B. subtilis JCK-1398 suppressed nematode migration and reduced nematode populations within pine tissues, effects attributed to the enhanced tree defense response. Field trials corroborated these findings, demonstrating a 72 % decrease in PWD incidence with aerial application of JCK-1398, confirming its potential for large-scale forest application. This biocontrol strategy, leveraging the stimulation of plant defense by B. subtilis JCK-1398, presents a promising and scalable, eco-friendly solution for managing PWD. Overall, this study provides new insights into the interactions between the bioagent, the host tree, and the pest nematode, offering an effective and sustainable approach to mitigate pine wilt disease.

A Study on Health Diagnosis of Zelkova serrata (Thunb.) Makino Using Hyperspectral Technique

Background and objective: Health diagnosis is essential for large, old trees that are designated and protected by the Act on the Preservation and Utilization of Natural Heritage and the Forest Protection Act. However, in the field, the overall health of trees is diagnosed by measuring the photosynthetic efficiency (PE) of some leaves. Therefore, this study aimed to examine the possibility of using hyper-spectral technology to replace the PE measurement as an approach for diagnosing the health of Zelkova serrata (Thunb.) Makino, which has a high rate of natural monument designation among South Korea’s natural heritage.Methods: The PE and hyper-spectral values were acquired from Zelkova leaves, and a Monte Carlo simulation was performed based on the spectral bands used to calculate vegetation indices (VI) in previous studies to select bands that have a high correlation with the PE. The explanatory power of these values on tree health was verified through a regression analysis of the VI and PE calculated from the selected bands, and the results of the study are as follows.Results: First, a variance analysis of the PE and VI of leaves found that there were differences depending on direction, and that the hyper-spectral values of leaves collected from the west were the most effective in measuring tree health. Second, it was found that it was effective to use 520 and 570 nm in the green region, 684 nm in the red region, 860 and 890 nm in the NIR region, 500 nm in the carotenoid region, and 531 nm in the xanthophyll region to derive the VI that replace PE metrics from the hyper-spectral values of leaves collected from the west. Third, PRI showed a very high effect with an explanatory power of 73.2% for the maximum quantum yield (Fv/Fm) regression equation. In other words, it was found that PRI can be used as an index derived from hyperspectral values to diagnose and record the healthy parts of Zelkova tree.Conclusion: By expanding the scope of this study to include Pinus densiflora and Ginkgo biloba, it is expected that if the utility and field applicability of this approach for diagnosing the health of large old trees are generally verified, it can be used for regular surveys of such trees designated as natural monuments in the future. Furthermore, it is expected that it can be expanded to diagnose park trees, street trees and the like, in addition to large, old trees.

Haplotype-resolved genome assembly and resequencing analysis provide insights into genome evolution and allelic imbalance in Pinus densiflora.

Haplotype-level allelic characterization facilitates research on the functional, evolutionary and breeding-related features of extremely large and complex plant genomes. We report a 21.7-Gb chromosome-level haplotype-resolved assembly in Pinus densiflora. We found genome rearrangements involving translocations and inversions between chromosomes 1 and 3 of Pinus species and a proliferation of specific long terminal repeat (LTR) retrotransposons (LTR-RTs) in P. densiflora. Evolutionary analyses illustrated that tandem and LTR-RT-mediated duplications led to an increment of transcription factor (TF) genes in P. densiflora. The haplotype sequence comparison showed allelic imbalances, including presence-absence variations of genes (PAV genes) and their functional contributions to flowering and abiotic stress-related traits in P. densiflora. Allele-aware resequencing analysis revealed PAV gene diversity across P. densiflora accessions. Our study provides insights into key mechanisms underlying the evolution of genome structure, LTR-RTs and TFs within the Pinus lineage as well as allelic imbalances and diversity across P. densiflora.

The Effects of Forest Gaps on the Physical and Ecological Stoichiometric Characteristics of Soil in Pinus densiflora Sieb. and Robinia pseudoacacia L. Forests

Forest gaps alter the environmental conditions of forest microclimates and significantly affect the biogeochemical cycle of forest ecosystems. This study examined how forest gaps and non-gap areas affect soil’s physical properties and eco-stoichiometric characteristics. Relevant theories and methods were employed to analyze the impact of forest gaps on nutrient cycling in Pinus densiflora Sieb. (PDS) and Robinia pseudoacacia L. (RPL) forests located in the Taishan Mountains. The results revealed that (1) forest gaps significantly enhanced the soil physical properties of PDS and RPL forests compared to non-gap areas (NPs). Notably, the bulk density of the soil decreased by 53%–12%, particularly in the surface layer (0–20 cm). Additionally, its non-capillary porosity increased by 44%–65%, while the clay and silt content rose by 39%–152% and 24%–130%, respectively. Conversely, the sand content decreased significantly, by 24%–32% (p < 0.05). (2) The contents of C, N, and P in the gap soil of PDS forests showed a significant increase compared to those in non-gap soil, with increases of 56%–131% for carbon, 107%–1523% for nitrogen, and 100%–155% for phosphorus. There was a significant drop of 10%–33% and 39%–41% in their C:N and C:P ratios, respectively (p < 0.05). The contents of C and P in the gap soil of the Robinia pseudo acacia L. Forest increased significantly, by 14%–22% and 34.4%–71%, respectively. Its C:P and N:P ratios significantly increased, by 14% to 404% and 11% to 41%, respectively (p < 0.05). (3) Compared with NPs, the forest gap significantly reduced the soil electrical conductivity and increased the soil pH. Additionally, compared to the soil at the gap’s edge, the surface soil in the gap’s center had noticeably higher concentrations of C, N, and P. (4) Key variables affecting the soil pH, silt content, bulk density, and overall porosity in forest gaps include the concentrations of carbon (C), nitrogen (N), and phosphorus (P) present and their ecological stoichiometric ratios. The findings showed that forest gaps had a considerable impact on the soil’s physical characteristics and ecological stoichiometry. They also had a high potential for providing nutrients, which might aid in the establishment of plantation plants.

Pinus densiflora 'Pendula' Weeping Japanese Red Pine

This document provides an overview of the Weeping Japanese Red Pine (Pinus densiflora ‘Pendula’), detailing its characteristics, growth habits, and care requirements. The tree is noted for its picturesque silhouette, with a crooked trunk and reddish-orange peeling bark. It thrives in full sun and well-drained, slightly acidic soil, and is suitable for USDA hardiness zones 3B through 7A2. The document also highlights its moderate drought tolerance, pest resistance, and potential issues such as needle blight and rusts. Additionally, it mentions several cultivars and their unique features. Original publication date October 1999.

The incursion process of Japanese red pine on the slope of the road

The incursion process of Japanese red pine on the slope of the road

Different patterns of fine-root exudation rates along soil depth of Pinus densiflora, Chamaecyparis obtusa, and Cryptomeria japonica in coniferous forests

Tree fine-root exudation and organic carbon compounds in the soil affect physiological functions through degradation by microorganisms around the roots and the enhancement of allelopathic effects on invasion attempts by other plant species. However, the underlying mechanism of fine-root action in vertically heterogeneous resource-distribution patterns along the soil profile is little known. Here, we quantified root exudation and its morphological and chemical traits in the soil layers down to 100-cm depth for three conifer species, Pinus densiflora (ectomycorrhiza), Chamaecyparis obtusa, and Cryptomeria japonica (arbuscular mycorrhiza), in a cool temperate Japanese forest. By using glass filter-trap method, root exudation rates in all three species varied with soil depth in a species dependent pattern. Specifically, the root exudation rate of P. densiflora was significantly higher in the middle soil layer, and lower in the topsoil layer, whereas the exudation rates significantly decreased in C. japonica and did not vary in C. obtusa along soil depth. Exudation strongly correlated with variation in root traits in C. obtusa and C. japonica but not in P. densiflora. These findings suggest that differences in exudation patterns among tree species are likely compensated for by structural modifications in fine roots in response to soil depth. In addition, the traits with mycorrhizal types might be related to adequate root exudation and enhanced soil-nutrient acquisition. Distinct differences among species in exudation, associated with vertical root distribution, will increase our understanding of root survival strategies for nutrient acquisition and carbon sequestration in forest tree species.

Shifts in fungal community diversity and potential function under natural forest succession and planted forest restoration in the Kunyu Mountains, East China.

Soil fungi participate in various ecosystem processes and are important factors driving the restoration of degraded forests. However, little is known about the changes in fungal diversity and potential functions under the development of different vegetation types during natural (secondary forest succession) and anthropogenic (reforestation) forest restoration. In this study, we selected typical forest succession sequences (including Pinus densiflora Siebold & Zucc., pine-broadleaf mixed forest of P. densiflora and Quercus acutissima Carruth., and Q. acutissima), as well as natural secondary deciduous broadleaved mixed forests and planted forests of Robinia pseudoacacia on Kunyu Mountain for analysis. We used ITS rRNA gene sequencing to characterize fungal communities and used the FUNGuild database to predict fungal functional groups. The results showed that forest succession affected fungal β-diversity, but not the α-diversity. There was a significant increase in Basidiomycota and a decrease in Ascomycota in the later successional stage, accompanied by an increase in the functional groups of ectomycorrhizal fungi (ECM). Conversely, planted forests exhibited decreased fungal α-diversity and altered community compositions, characterized by fewer Basidiomycota and more Ascomycota and Mucoromycota. Planted forests led to a decrease in the relative abundances of ECM and an increase in animal pathogens. The TK content was the major factor explaining the distinction in fungal communities among the three successional stages, whereas pH, AP, and NH4 + were the major factors explaining community variations between natural and planted forests. Changes in vegetation types significantly affected the diversity and functional groups of soil fungal communities during forest succession and reforestation, providing key insights for forest ecosystem management in temperate forests.

The Effects of Termites and Beetle Larvae on the Decomposition of Pinus densiflora and Quercus acutissima in South Korea over a 6-Year Period

The Effects of Termites and Beetle Larvae on the Decomposition of Pinus densiflora and Quercus acutissima in South Korea over a 6-Year Period

Effect of Planting Ground Treatments Using Artificial Rainfall Slope Simulating Degraded Forestland on Drought Stress Susceptibility of Pinus densiflora

Trees in degraded forest areas are generally exposed to water stress due to harsh environmental conditions, threatening their survival. This study simulated the environmental conditions of a degraded forest area by constructing an artificial rainfall slope and observing the physiological responses of Pinus densiflora to control, mulching, and waterbag treatments. P. densiflora exhibited distinct isohydric plant characteristics of reducing net photosynthetic rate and stomatal transpiration rate through regulating stomatal conductance in response to decreased soil moisture, particularly in the control and waterbag treatments. Additionally, the trees increased photochemical quenching, such as Y(NPQ), to dissipate excess energy as heat and minimize damage to the photosynthetic apparatus. However, these adaptive mechanisms have temporal limitations, necessitating appropriate measures. Under extreme drought stress (DS45), mulching treatment showed 4.5 times and 2.2 times higher in PIabs and SFIabs than in the control, and after the recovery period (R30), waterbag and mulching treatment showed similar levels, while PIabs and SFIabs in the control were only 45% and 75% of those in the mulching and waterbag treatments, respectively. Specifically, mulching extended the physiological mechanisms supporting survival by more than a week, making it the most effective method for enhancing the planting ground in degraded forest areas. Although the waterbag treatment was less effective than mulching treatment, it still significantly contributed to forming better growth conditions compared to the control. These findings highlight the potential for mulching and waterbag treatments to enhance forest restoration efforts, suggesting future research and application could lead to more resilient reforested areas capable of withstanding climate change-induced drought conditions.

Development and validation of analytical HPLC for phenolics in Pinus densiflora bark extract

Development and validation of analytical HPLC for phenolics in Pinus densiflora bark extract

Comparisons of tracheid lengths in Pinus densiflora Siebold & Zucc.: earlywood versus latewood and province versus province

Abstract The tracheid length (TL) in conifer species is a primary factor to determine quality of paper and wood products. However, TL in Pinus densiflora Siebold & Zucc., a dominant conifer species in Korea, has not been monitored systematically across the country yet. To this end, the TL of early- and latewoods of Korean red pine from 16 provinces of the Republic of Korea was measured and compared to verify the differences (1) between the monitoring years (2014–2018), (2) between early- and latewoods of the trees from the same provinces, and (3) between the early- and latewoods from different provinces. Analysis of 31,500 tracheids revealed that the variation of TL of early- and latewood from two and six out of 16 sites, respectively, were not statistically meaningful and the TL of latewood displayed a lower annual variation than that of the earlywood during the monitoring years. The TL of the latewood was longer than that of the earlywood; however, four out of 16 sites showed shorter TL for the latewood. So, it was verified that the relationship between the TL of the early- and latewood can change. Moreover, the TL was longer for the trees located in the southeast regions.

Red Pine Bark Extract Alleviates Akt/GSK-3β Signaling Disruption in the Hippocampus of Streptozotocin-Induced Diabetic Sprague-Dawley Rats.

This study investigates whether red pine (Pinus densiflora Sieb. et Zucc.) bark extract (PBE) can alleviate diabetes and abnormal apoptosis signaling pathways in the hippocampus of streptozotocin (STZ)-induced diabetic Sprague-Dawley (SD) rats. Two dosages of PBE (15 and 30 mg/kg of body weight/day) were administered orally to STZ-induced diabetic SD rats for 20 days. Blood glucose level and body weight were measured once per week. After 20 days of oral administration of PBE, the rat hippocampus was collected, and the production of Akt, p-Akt, GSK-3β, p-GSK-3β, tau, p-tau, Bax, and Bcl-2 proteins were determined by western blot analysis. A decrease in blood glucose level and recovery of body weight were observed in PBE-treated diabetic rats. In the Akt/GSK-3β/tau signaling pathway, PBE inhibited diabetes-induced Akt inactivation, GSK-3β inactivation, and tau hyperphosphorylation. The protein production ratio of Bax/Bcl-2 was restored to the control group level. These results suggest that PBE, rich in phenolic compounds, can be used as a functional food ingredient to ameliorate neuronal apoptosis in diabetes mellitus.

Evaluation of the Restoration Effects of Rooftop Greening Areas Created by Applying an Ecological Restoration Method

Green roofs provide various ecosystem services, including habitats for diverse organisms in urban areas where natural space is very scarce. This study aims to evaluate the restoration effects of green roofs created by applying an ecological restoration method to reinforce habitat function. The reference ecosystem selected for the ecological restoration of a roof was a Korean red pine stand established on Mt. Bulam, considering the soil depth, light, moisture conditions, etc., compared with the roof’s environmental conditions. Ecological restoration was carried out by planting two-year-old pine seedlings and scattering surface soil collected from the pine stands. The pine trees showed geometrical growth in height and diameter and a high water-use efficiency. The ecological restoration of the green roofs demonstrated an ecological function for improving the urban climate through the mitigation of the urban heat island effect and high productivity, showing different functions depending on the greening method. The composition and diversity of vegetation and insects at the ecological restoration site were similar to those at the reference site, whereas the landscape architecture sites, which were created using the landscape architecture method, were different from the reference site. These results confirm that applying the ecological restoration method for rooftop greening resulted in better biological habitat function than applying existing landscape architecture methods.

Comparison of biogenic volatile organic compounds emissions from representative urban tree species in South Korea and evaluation of standard emission rate models

Although trees generally help alleviate global warming, they generate biogenic volatile organic compounds (BVOCs) that may contribute to air pollution and exacerbate climate change. To estimate BVOCs emission rates, several models have been widely used to calculate the standard emission rate (ERs) that takes temperature and light intensity into account. In this study, the effects of temperature and light intensity on the isoprene and monoterpene emissions from various tree species were investigated. Four broad-leaved trees (Platanus occidentalis, Quercus mongolica, Zelkova serrata, and Acer palmatum) and three coniferous trees (Pinus densiflora, Metasequoia glyptostroboides, and Pinus koraiensis) were investigated in August 2022 for the comparison by the species. Emissions from Pinus densiflora were also measured in May for comparison with different climate conditions. Platanus occidentalis revealed the highest emission of isoprene, followed by Quercus mongolica, Zelkova serrata, and Acer palmatum. It was found that the isoprene emissions from Zelkova serrata and Quercus mongolica had a stronger correlation with light intensity than those from Platanus occidentalis. In contrast, the isoprene emissions from Platanus occidentalis exhibited the strongest correlation with temperature compared to other trees concerned. The monoterpene emission from Metasequoia glyptostroboides showed the highest correlation with light intensity (r2 = 0.662). Among the monoterpenes, α-pinene was the most affected by light intensity. Pinus densiflora was affected more by light intensity in May. The ERs estimation using the G93 model confirmed this pattern. Therefore, this study suggests that both light and temperature be taken into account in order to obtain more reliable ERs data of monoterpenes.