In plants,the lysine and histidine transporter(LHT)family represent a class of proteins that mediate the uptake,translocation,and utilization of amino acids.The tea plant(Camellia sinensis)is a perennial evergreen wit...In plants,the lysine and histidine transporter(LHT)family represent a class of proteins that mediate the uptake,translocation,and utilization of amino acids.The tea plant(Camellia sinensis)is a perennial evergreen with a relatively high level of amino acids.However,systematic identification and molecular characterization of the LHT gene family has rarely been reported in tea plants.In this study,22 CsLHTs were identified from the‘Shuchazao’genome and classified into two groups.The modeled three-dimensional structure and the conserved domains presented a high similarity among the LHTs proteins.Moreover,it was predicted that a few genes were conserved through the analysis of the physiochemical characters,structures and cis-elements in promoters.The expression patterns in tea plants revealed that CsLHT7 was mainly expressed in the roots,and CsLHT4 and CsLHT11 exhibited relatively high expression in both the roots and leaves.Moreover,the expression of all three genes could be induced by organic nitrogen.Additionally,heterogeneous expression of CsLHT4,CsLHT7 and CsLHT11 in Arabidopsis thaliana decreased the aerial parts biomass compared with that in WT plants while significantly increased the rosette biomass only for CsLHT11transgenic plants versus WT plants.Overall,our results provide fundamental information about CsLHTs and potential genes in N utilization for further analysis in tea plants.展开更多
BACKGROUND Ankylosing spondylitis(AS)is a chronic immune-mediated inflammatory disease.The prevailing theory links AS onset to infections in susceptible individuals.Furthermore,infections may impair the immune respons...BACKGROUND Ankylosing spondylitis(AS)is a chronic immune-mediated inflammatory disease.The prevailing theory links AS onset to infections in susceptible individuals.Furthermore,infections may impair the immune responses.Numerous studies have investigated links between AS and various infections-bacterial,viral,fungal,and other microorganism infections.However,limited attention has been given to the association between AS and Clonorchis sinensis(C.sinensis)infection.CASE SUMMARY A 27-year-old male with a 10-yr history of AS presented to our hospital with inflammatory lower back pain as the primary manifestation.Ten years ago,the patient had achieved a stable condition after treatment with biological agents.However,he experienced a recurrence of lumbosacral pain with an unexplained cause 10 d before hospital admission.A lumbosacral magnetic resonance imaging(MRI)scan revealed bone marrow edema in the left sacroiliac joint,and laboratory indicators were elevated.Moreover,the presence of C.sinensis eggs was detected in the stool.The patient was prescribed praziquantel,resulting in the disap-pearance of C.sinensis eggs in subsequent routine stool tests and relief from lumbosacral pain.A follow-up MRI scan performed after 4 months revealed a reduction in bone marrow edema around the left sacroiliac joint.CONCLUSION C.sinensis infections could potentially trigger the exacerbation of AS.Clinicians should pay attention to investigating the presence of infections.INTRODUCTION Ankylosing spondylitis(AS)is a chronic inflammatory and rheumatic disease resulting from an imbalance between innate and acquired immune responses[1].While it can affect any part of the spine,its primary symptoms are persistent back pain and stiffness in the lower back and pelvis.The prevalence of AS per 10000 individuals is 23.8 in Europe,31.9 in North America,16.7 in Asia,10.2 in Latin America,and 7.4 in Africa[2].Infections commonly occur in the first 3 months and may act as potential triggers for the first symptoms of AS,often manifesting as gastrointestinal,urinary tract,and respiratory infections of microbiological origin[3,4].Clonorchis sinensis(C.sinensis)infection is a severe parasitic disease affecting millions globally,especially prevalent in China,South Korea,the Far East of Russia,and Vietnam,with an estimated 15 million cases[5].Transmission occurs through the consumption of undercooked freshwater fish containing metacercariae.Adult C.sinensis parasites then establish themselves within the human hepatobiliary system[6].C.sinensis infection triggers the activation of sphingosine 1-phosphate receptor 2,leading to the injury and fibrosis of the hepatobiliary[7].Recent research in a rat model found that C.sinensis infection increases the risk of hepatocellular carcinoma by stimulating hepatic progenitor cell proliferation[8].Complications of C.sinensis infection include cholestasis,cholangitis,biliary system fibrosis,and in severe cases,the development of cholangiocarcinoma[9].Consequently,the primary preventive measure is to abstain from consuming raw or undercooked freshwater fish.Praziquantel is the recommended and effective treatment for this infection[10].While there is existing literature on the coexistence of AS and parasitic infections,there is limited research specifically addressing the simultaneous presence of AS and C.sinensis infection.This case report details a rare scenario of AS coexisting with C.sinensis infection,underscoring the potential impact of C.sinensis infection on AS disease activity.展开更多
The ATP-binding cassette(ABC)transporter is a gene superfamily in plants.ATP-binding cassette subfamily C(ABCC)protein is a multidrug resistance-associated(MRP)transporter.They play various roles in plant growth,devel...The ATP-binding cassette(ABC)transporter is a gene superfamily in plants.ATP-binding cassette subfamily C(ABCC)protein is a multidrug resistance-associated(MRP)transporter.They play various roles in plant growth,development,and secondary metabolite transport.However,there are few studies on ABCC transporters in tea plants.In this study,genome-wide association study(GWAS)analysis of epigallocatechin gallate(EGCG)content in 108 strains of Kingbird revealed that CsABCCs may be involved in EGCG transport.We identified 25 CsABCC genes at the genomic level of the tea plant,their phylogenetic tree,gene structure,targeted miRNA and other bioinformatics were analyzed.The expression patterns of CsABCCs in eight different tissues and abiotic stress indicate that they have potential roles in regulating the growth,development,and defense of tea plants.The correlation analysis revealed that the expression of the CsABCC11 gene was closely related to the EGCG content in tea buds of 108 strains of the Kingbird,and the subcellular localization experiments in tobacco showed that CsABCC11 protein was localized on the plasma membrane.The virus-induced gene silencing(VIGS)strategy in tea plants further verified that CsABCC11 was involved in EGCG accumulation.Our study laid a foundation for studying the biological function of CsABCC and provided a new candidate molecular marker gene for further EGCG-related variety breeding,which will be of great interest to breeders.展开更多
Chinese Assam tea(Camellia sinensis var.assamica)is an important tea crop with a long history of cultivation in Yunnan,China.Despite its potential value as a genetic resource,its genetic diversity and domestication/br...Chinese Assam tea(Camellia sinensis var.assamica)is an important tea crop with a long history of cultivation in Yunnan,China.Despite its potential value as a genetic resource,its genetic diversity and domestication/breeding history remain unclear.To address this issue,we genotyped 469 ancient tea plant trees representing 26 C.sinensis var.assamica populations,plus two of its wild relatives(six and three populations of C.taliensis and C.crassicolumna,respectively)using 16 nuclear microsatellite loci.Results showed that Chinese Assam tea has a relatively high,but comparatively lower gene diversity(H_(S)=0.638)than the wild relative C.crassicolumna(H_S=0.658).Clustering in STRUCTURE indicated that Chinese Assam tea and its two wild relatives formed distinct genetic groups,with considerable interspecific introgression.The Chinese Assam tea accessions clustered into three gene pools,corresponding well with their geographic distribution.However,New Hybrids analysis indicated that 68.48%of ancient Chinese Assam tea plants from Xishuangbanna were genetic intermediates between the Puer and Lincang gene pools.In addition,10%of the ancient Chinese Assam tea individuals were found to be hybrids between Chinese Assam tea and C.taliensis.Our results suggest that Chinese Assam tea was domesticated separately in three gene pools(Puer,Lincang and Xishuangbanna)in the Mekong River valley and that the hybrids were subsequently selected during the domestication process.Although the domestication history of Chinese Assam tea in southwestern Yunnan remains complex,our results will help to identify valuable genetic resources that may be useful in future tea breeding programs.展开更多
This study investigates the nitrogen (N), phosphorous (P), and potassium (K) contents in raw biomasses of Camellia sinensis, Gliricidia sepium, and Musa acuminata. Therein, the highest N and P content was seen in Came...This study investigates the nitrogen (N), phosphorous (P), and potassium (K) contents in raw biomasses of Camellia sinensis, Gliricidia sepium, and Musa acuminata. Therein, the highest N and P content was seen in Camellia sinensis 116.80 ± 0.08 mg and 66.00 ± 0.14 mg respectively. The highest K content (106.80 ± 0.04 mg) was observed in Musa acuminata. Next, all three types of plant materials were allowed to decompose in water for 3 weeks, and a sample from each was analyzed for NPK after the 1st, 2nd, and 3rd week during decomposition. A significant increase in the release of N, P, and K by the Camellia sinensis to water (P Musa acuminate were not significantly changed (P > 0.05) over time. The ratio for N:P:K was calculated for raw biomass samples and decomposed samples to find the best fitting N:P:K ratio to apply to young tea plants as organic fertilizers. In addition to that, the microbial insight of these organic compounds was analyzed by observing how microbial population increased with decomposition by the enumeration of the total microbial count. A considerable increment in total microbial count was observed up to 3.28 × 10<sup>6</sup>, 1.21 × 10<sup>10</sup>, 2.18 × 10<sup>8</sup>, and 6.49 × 10<sup>7</sup> CFU/ml for Camellia sinensis, Gliricidia sepium, Musa accuminata (leaves), and Musa accuminata (trunk) respectively. The presence of phosphate solubilizing bacteria (PSB) and nitrogen solubilizing bacteria (NSB) throughout the decomposition period was confirmed by their growth on NBRIP and a modified nutrient medium that was specifically designed for the identification of ammonifiers respectively. Prepared fertilizer samples were applied to young tea plants that were grown in the Mawanella area in Sri Lanka (7°15'12.42"N 80°26'47.62"E) and according to the results, it is clear that fertilizer mixture 1 (N:P:K, 10:5:10, tea dust + Gliricidia + banana trunk) and fertilizer mixture 2 (N:P:K, 10:5:10, tea dust + Gliricidia + banana leaves) has the potential to increase the growth of young tea plants.展开更多
Seventeen morphological and anatomical characteristics of the leaves were selected from five natural populations to explore the variation in leaf traits of Lits ea core ana var.sinensis and the effects of geographical...Seventeen morphological and anatomical characteristics of the leaves were selected from five natural populations to explore the variation in leaf traits of Lits ea core ana var.sinensis and the effects of geographical environment on these variations.Nested analysis of variance,multiple comparisons,principal component analysis(PCA),and correlation analysis were conducted to explore the variations within and between populations and their correlation with geographical and climatic factors.Significant differences in the 17 leaf traits were observed within and among populations.On average,the relative contribution of within population variation to total variation was 24.8%,which was lower than among population variation(54.6%).The average differentiation coefficient of the traits was 65.8%,and the average coefficient of variation 11.8%,ranging from6.7%for main vein thickness to 21.4%for petiole length.The PC A results showed that morphological characteristics were divided into two categories,and the level of variation was greater than that of leaf anatomy.Most of the leaf traits were significantly correlated with geography and climate and showed a gradual variation with longitude,latitude,and altitude.In areas with high temperatures,less rainfall,and strong seasonal rainfall,the leaves are larger,longer and thicker.This study shows that variations in leaf traits of L.coreana var.sinensis mainly come from variations among populations.The level of trait differentiation among populations is high and the level of variation within populations low.These findings help further understand leaf morphological characteristics of this species and can provide a valuable reference for the protection and sustainable utilization of this natural resource.展开更多
Chinese mahogany(Toona sinensis) is of considerable medical and economic importance, and its genome has been deciphered. However, the process underlying its polyploidy is unclear, and the chromosomal evolutionary traj...Chinese mahogany(Toona sinensis) is of considerable medical and economic importance, and its genome has been deciphered. However, the process underlying its polyploidy is unclear, and the chromosomal evolutionary trajectory is poorly understood. Here, by reanalysing the T.sinensis genome, we found evidence of a tetraploidization event(T. sinensis special tetraploidization, TST) that occurred approximately 15-17 million years ago(MYA) after the core eudicot-common hexaploidization(ECH or gamma) event. We characterized the synonymous nucleotide substitution rates(Ks values) of collinear genes and found that T. sinensis genes affected by the TST evolve at a slower rate than Acer yangbiense genes. Furthermore, we identified homologous genes related to polyploidization and speciation and constructed multiple alignments with different reference genomes. Notably, the significant balance of gene retention and loss characterized in the two TST-derived subgenomes suggests an autopolyploid nature of the TST. Moreover, we deduced the chromosomal karyotypes of the two subgenomes and identified 7chromosomal fusions that have shaped the T. sinensis genome;more information is available on a newly constructed karyotype platform(http://www.cgrpoee.top/Toona_sinensis/index.html). The T. sinensis genome preserves the ancestral chromosome structure of dicotyledons well and could serve as a good reference for understanding genomic changes in other Meliaceae and Sapindales plants. In addition, we verified that tandem duplication and the ECH have promoted the expansion of terpene synthase(TPS) genes;conversely, the TST seems to have inhibited expansion of these genes. This present effort has clarified the polyploidy events of the T. sinensis genome, filled gaps in the history of karyotype evolution, and laid a solid foundation for further genomic studies in the Meliaceae research community and beyond.展开更多
In this study, volatile compounds present in Toona sinensis (A. Juss.) Roem (TS) were investigated and their characteristic aromatic components were identified using Headspace Solid-phase Microextraction (HS-SPME) fol...In this study, volatile compounds present in Toona sinensis (A. Juss.) Roem (TS) were investigated and their characteristic aromatic components were identified using Headspace Solid-phase Microextraction (HS-SPME) followed by Gas Chromatography-Mass Spectrometry (GC-MS) and Gas Chromatography-Olfactometry (GC-O). The optimum conditions for extracting the volatiles from TS were achieved with the experimental parameters including the use of a 65 μm polydimethylsiloxane/divinyl benzene (PDMS/DVB) fibre, an extraction temperature of 40℃ and an extraction time of 30 min. Under these conditions, 56 volatile compounds were separated and 53 were identified by GC-MS. Among them, 21 sulfide compounds (42.146%) and 27 terpenes(55.984%) were found to be the major components. The sample was analyzed by GC-O and 26 elutes were sniffed and their sensory descriptions evaluated by an odor panelists. Analysis of the data indicated, two compounds cis and trans isomers of 2-Mercapto-3,4-dimethyl-2,3-dihydrothiophene were major contributors to the characteristic aroma of TS.展开更多
Various genetic and biochemical characteristics exist in tea plant cultivars,and they largely determine production suitability and tea quality.Here,we performed transcriptomic and metabolomic analyses of young shoots ...Various genetic and biochemical characteristics exist in tea plant cultivars,and they largely determine production suitability and tea quality.Here,we performed transcriptomic and metabolomic analyses of young shoots of seven tea cultivars and identified major regulatory transcription factors(TFs)for the characteristic metabolites in different cultivars based on weighted gene co-expression network analysis(WGCNA).Phenotypically,we found that‘Tieguanyin’(TGY)and‘Fujian Shuixian’(FJSX),which are suitable for oolong tea,had higher catechin contents.The metabolites of‘Jinxuan’(JX)were more prominent,especially the contents of phenolic acids,flavonoids,terpenes,and tannins,which were higher than those of the other six cultivars.Moreover,‘Fudingdabai’(FDDB),which is suitable for white tea,was rich in amino acids,linolenic acid,and saccharides.At the molecular level,hydroxycinnamoyl CoA quinate hydroxycinnamoyl transferase(HCT)(CsTGY12G0001876,and CsTGY06G0003042)led to the accumulation of chlorogenic acid in TGY.The main reason for the higher l-ascorbic acid content in FJSX was the high expression levels of L-galactono-1,4-lactone hydrogenase(GalLDH)(CsTGY13G0000389)and Myo-inositol oxygenase(MIOX)(CsTGY14G0001769,and CsTGY14G0001770),which were regulated by WRKY(CsTGY11G0001197).Furthermore,FDDB,‘Longjing 43’(LJ43),‘Shuchazao’(SCZ)and‘Baihaozao’(BHZ)had higher free fatty acid contents,among which MYB(CsTGY14G0002344)may be a hub gene for the regulation of palmitoleic acid accumulation.More importantly,we found that the shoots of TGY were green with purple,mainly due to the accumulation of anthocyanins and the downregulation of the Mg-protoporphyrin IX nonomethyl ester cyclase(MPEC)(CsTGY10G0001989)gene that affects chlorophyll synthesis.These results will provide a theoretical reference for tea cultivar breeding and suitability.展开更多
Dear Editor,Tea plant(Camellia sinensis(L.)O.Kuntze)is one of the world’s most important non-alcoholic beverages,with great economic,health,and cultural value.Recently,several genomes of C.sinensis var.assamica(CSA)(...Dear Editor,Tea plant(Camellia sinensis(L.)O.Kuntze)is one of the world’s most important non-alcoholic beverages,with great economic,health,and cultural value.Recently,several genomes of C.sinensis var.assamica(CSA)(Yunkang 10),C.sinensis var.sinensis(CSS)(Shuchazao,Biyun,Longjing 43,Tieguanyin,Huangdan),and ancient tea plant(DASZ)have been deciphered[1-3].展开更多
Sesquiterpenes are the major pharmacodynamic components of agarwood,a precious traditional Chinese medicine obtained from the resinous portions of Aquilaria sinensis trees that form in response to environmental stress...Sesquiterpenes are the major pharmacodynamic components of agarwood,a precious traditional Chinese medicine obtained from the resinous portions of Aquilaria sinensis trees that form in response to environmental stressors.To characterize the sesquiterpene synthases responsible for sesquiterpene production in A.sinensis,a bioinformatics analysis of the genome of A.sinensis identifi ed six new terpene synthase genes,and 16 sesquiterpene synthase genes were identifi ed as type TPS-a in a phylogenetic analysis.The expression patterns for eight of the sesquiterpene synthase genes after treatment with various hormones or hydrogen peroxide were analyzed by real-time quantitative PCR.The results suggest that 100μM methyl jasmonate,ethephon,(±)-abscisic acid or hydrogen peroxide could be eff ective short-term eff ectors to increase the expression of sesquiterpene synthase genes,while 1 mM methyl salicylate may have long-term eff ects on increasing the expression of specifi c sesquiterpene synthase genes(e.g.,As-SesTPS,AsVS,AsTPS12 and AsTPS29).The expression changes in these genes under various conditions refl ected their specifi c roles during abiotic or biotic stresses.Heterologous expression of a novel A.sinensis sesquiterpene synthase gene,AsTPS2,in Escherichia coli produced a major humulene product,so AsTPS2 is renamed AsHS1.AsHS1 is diff erent from ASS1,AsSesTPS,and AsVS,for mainly producingα-humulene.Based on the predicted space conformation of the AsHS1 model,the small ligand molecule may bind to the free amino acid by hydrogen bonding for the catalytic function of the enzyme,while the substrate farnesyl diphosphate(FPP)probably binds to the free amino acid on one side of the RxR motif.Arg450,Asp453,Asp454,Thr457,and Glu461 from the NSE/DTE motif and D307 and D311 from the DDxxD motif were found to form a polar interaction with two Mg^(2+)clusters by docking.The Mg^(2+)-bound DDxxD and NSE/DTE motifs and the free RXR motif are jointly directed into the catalytic pocket of AsHS1.Comparison of the tertiary structural models of AsHS1 with ASS1 showed that they diff ered in structures in several positions,such as surrounding the secondary catalytic pocket,which may lead to diff erences in catalytic products.Based on the results,biosynthetic pathways for specifi c sesquiterpenes such asα-humulene in A.sinensis are proposed.This study provides novel insights into the functions of the sesquiterpene synthases of A.sinensis and enriches knowledge on agarwood formation.展开更多
The appropriate reference gene is a prerequisite for accurate normalization of gene expression level,and research on suitable reference genes in clam Cyclina sinensis is scarce.To improve the situation,we selected fiv...The appropriate reference gene is a prerequisite for accurate normalization of gene expression level,and research on suitable reference genes in clam Cyclina sinensis is scarce.To improve the situation,we selected five commonly used housekeeping genes,including β-actin,Elongation factor 1-α(EF1-α),Glyceraldehyde-3-pho sphate dehydrogenase(GAPDH),40S ribosomal protein S18(RPS18),and Tubulin a(TUB-α),then evaluated their expression stability in different adult tissues and under different experimental treatments(salinity stress and Vibrio parahaemolyticus infection).Their expression stability was analyzed by three frequently used programs,geNorm,NormFinder,and BestKeeper.This analysis indicated that multiple genes should be used for normalization,and we concluded that the reference gene combination GAPDH-RPS18-β-actin,should be used for qRT-PCR analysis in different tissues of C.sinensis under normal physiological conditions.For the clams under salinity stress and Vibrio infection,EF1-α-GAPDHRPS18 was recommended as the gene combination for qRT-PCR normalization.TUB-αwas generally poorly ranked by all programs,and should not be used in future studies.This study should provide fundamental support for accurate quantitative gene expression analysis of this species.展开更多
Many attentions have been previously focused to identify the multiple biochemical components related to tea quality and health benefits,however, the natural variation of biochemical components present in tea germplasm...Many attentions have been previously focused to identify the multiple biochemical components related to tea quality and health benefits,however, the natural variation of biochemical components present in tea germplasm has not been adequately evaluated. In this study, the main biochemical components, leaf morphological and yield characteristics were evaluated for four rounds of tea leaves in a panel of 87 elite tea cultivars suitable for black, green, or oolong tea. Significant variations were observed among the tea cultivars, as well as seasonal differences in the levels of the free amino acid(FAA), caffeine(CAF), tea polyphenols(TP), water extract(WE) and TP to FAA ratio(TP/FAA). Results showed that the average levels of FAA showed a seasonal change, with the highest level of 4.0% in the 1st spring tea in the cultivars suitable for green tea and the lowest of 3.2% in summer tea in the cultivars suitable for black tea. The average CAF content was highest 3.2% in the cultivars suitable for oolong tea in the 1st spring and the lowest 2.5% in the cultivars suitable for green tea in summer. Limited seasonal and varietal variations were noticed in the average levels of WE among the three categories of tea. In addition, significant natural variation of the morphological characteristics, bud length varying from 2.5 cm to 8.7 cm, bud density from 190.3 buds · m-2to 1 730.3 buds · m-2, mature leaves biomass from 128.4 kg · hm-2to 2 888.4 kg · hm-2, and yield component traits of 100 buds(one bud with two leaves) dry weight from 3.7 g to37.7 g, tea yield/round from 444.6 kg · hm-2to 905.3 kg · hm-2, were observed. The aim of our evaluation was not only to identify the advantages of seasonal and clonal variations but also to provide a new viewpoint for their further application. Representative accessions were selected from the germplasm to promote the establishment of an inherent biochemical constituent expressing the quality of black, green, and oolong tea. The findings might be utilized to establish early selection criteria to enhance the tea breeding and production program.展开更多
We conducted experiments in an artificial stream tank with wild juvenile Chinese sturgeon Acipenser sinensis captured in the Yangtze Estuary to test the null hypothesis that their feeding efficiency on Barcheek goby R...We conducted experiments in an artificial stream tank with wild juvenile Chinese sturgeon Acipenser sinensis captured in the Yangtze Estuary to test the null hypothesis that their feeding efficiency on Barcheek goby Rhinogobius giurinus was not affected by sand vs. smooth glass substrate. Gobies are among the most common prey eaten by wild juvenile A. sinensis in the estuary. Test results found neither substrate type significantly affected feeding efficiency by juveniles. Previous research found a strong innate habitat preference of A. sinensis for sand substrate. The present results indicate that the preference for sand is not related to efficiently capturing R. giurinus on sand, but is an adaptation predisposing juvenile A. sinensis to seek sandy substrate where R. giurinus and other benthic forage are the most abundant in the Yangtze Estuary.展开更多
Studying the dynamics of plant populations is crucial to the conservation and management of endangered plants.The diameter at breast height(DBH),tree height,crown width,and environmental factors of a total of 15 plots...Studying the dynamics of plant populations is crucial to the conservation and management of endangered plants.The diameter at breast height(DBH),tree height,crown width,and environmental factors of a total of 15 plots in five populations in Guizhou Province,China were measured in this study.The method of substituting diameter at breast height for age was used to divide the population into 7 age classes.The age structure,static life table,and relationship between the population characteristics and environmental factors of the Litsea coreana Levl.var.sinensis population were studied.Moreover,the time series model was used to predict the population dynamics.Results showed that the age structure of population in Zhengan County(Population ZA)had an inverted Jshape with abundant seedlings and insufficient middle-aged and elderly individuals.The age structures of populations in Daozhen County(Population DZ),Kaiyang County(KY),Meitan County(Population MT),and Xishui County(Population XS)were spindle-shaped with few young individuals and many middle-aged and elderly individuals.The mortality rate of each population fluctuated with the increase in age class,and the populations were extremely unstable.The survival curve was close to the Deevey III type,and the degree of deviation was related to the lack of young individuals.After the age stages II,IV,and VI,the number of aged plants in the different populations initially increased then decreased,and population stability was difficult to maintain.Redundancy analysis showed that the DBH,tree height and crown width of the population decreased with the increase of annual mean temperature,and the population density was restricted by soil nutrient conditions to a certain extent.The results of this work provide scientific basis for the conservation and sustainable utilization of natural populations of L.coreana var.sinensis in Guizhou Province,China.展开更多
基金supported by the National Key Research and Development Program of China(Grant No.2018YFD1000600)the National Natural Science Foundation of China(Grant No.32070376)。
文摘In plants,the lysine and histidine transporter(LHT)family represent a class of proteins that mediate the uptake,translocation,and utilization of amino acids.The tea plant(Camellia sinensis)is a perennial evergreen with a relatively high level of amino acids.However,systematic identification and molecular characterization of the LHT gene family has rarely been reported in tea plants.In this study,22 CsLHTs were identified from the‘Shuchazao’genome and classified into two groups.The modeled three-dimensional structure and the conserved domains presented a high similarity among the LHTs proteins.Moreover,it was predicted that a few genes were conserved through the analysis of the physiochemical characters,structures and cis-elements in promoters.The expression patterns in tea plants revealed that CsLHT7 was mainly expressed in the roots,and CsLHT4 and CsLHT11 exhibited relatively high expression in both the roots and leaves.Moreover,the expression of all three genes could be induced by organic nitrogen.Additionally,heterogeneous expression of CsLHT4,CsLHT7 and CsLHT11 in Arabidopsis thaliana decreased the aerial parts biomass compared with that in WT plants while significantly increased the rosette biomass only for CsLHT11transgenic plants versus WT plants.Overall,our results provide fundamental information about CsLHTs and potential genes in N utilization for further analysis in tea plants.
基金Supported by Chongqing Municipal Health Commission's Key Discipline Construction Project of Traditional Chinese Medicine Bi Disease,Yu Traditional Chinese Medicine(2021),No.16.
文摘BACKGROUND Ankylosing spondylitis(AS)is a chronic immune-mediated inflammatory disease.The prevailing theory links AS onset to infections in susceptible individuals.Furthermore,infections may impair the immune responses.Numerous studies have investigated links between AS and various infections-bacterial,viral,fungal,and other microorganism infections.However,limited attention has been given to the association between AS and Clonorchis sinensis(C.sinensis)infection.CASE SUMMARY A 27-year-old male with a 10-yr history of AS presented to our hospital with inflammatory lower back pain as the primary manifestation.Ten years ago,the patient had achieved a stable condition after treatment with biological agents.However,he experienced a recurrence of lumbosacral pain with an unexplained cause 10 d before hospital admission.A lumbosacral magnetic resonance imaging(MRI)scan revealed bone marrow edema in the left sacroiliac joint,and laboratory indicators were elevated.Moreover,the presence of C.sinensis eggs was detected in the stool.The patient was prescribed praziquantel,resulting in the disap-pearance of C.sinensis eggs in subsequent routine stool tests and relief from lumbosacral pain.A follow-up MRI scan performed after 4 months revealed a reduction in bone marrow edema around the left sacroiliac joint.CONCLUSION C.sinensis infections could potentially trigger the exacerbation of AS.Clinicians should pay attention to investigating the presence of infections.INTRODUCTION Ankylosing spondylitis(AS)is a chronic inflammatory and rheumatic disease resulting from an imbalance between innate and acquired immune responses[1].While it can affect any part of the spine,its primary symptoms are persistent back pain and stiffness in the lower back and pelvis.The prevalence of AS per 10000 individuals is 23.8 in Europe,31.9 in North America,16.7 in Asia,10.2 in Latin America,and 7.4 in Africa[2].Infections commonly occur in the first 3 months and may act as potential triggers for the first symptoms of AS,often manifesting as gastrointestinal,urinary tract,and respiratory infections of microbiological origin[3,4].Clonorchis sinensis(C.sinensis)infection is a severe parasitic disease affecting millions globally,especially prevalent in China,South Korea,the Far East of Russia,and Vietnam,with an estimated 15 million cases[5].Transmission occurs through the consumption of undercooked freshwater fish containing metacercariae.Adult C.sinensis parasites then establish themselves within the human hepatobiliary system[6].C.sinensis infection triggers the activation of sphingosine 1-phosphate receptor 2,leading to the injury and fibrosis of the hepatobiliary[7].Recent research in a rat model found that C.sinensis infection increases the risk of hepatocellular carcinoma by stimulating hepatic progenitor cell proliferation[8].Complications of C.sinensis infection include cholestasis,cholangitis,biliary system fibrosis,and in severe cases,the development of cholangiocarcinoma[9].Consequently,the primary preventive measure is to abstain from consuming raw or undercooked freshwater fish.Praziquantel is the recommended and effective treatment for this infection[10].While there is existing literature on the coexistence of AS and parasitic infections,there is limited research specifically addressing the simultaneous presence of AS and C.sinensis infection.This case report details a rare scenario of AS coexisting with C.sinensis infection,underscoring the potential impact of C.sinensis infection on AS disease activity.
基金supported by the Guizhou University Talent Introduction Program([2021]05)Guizhou University Cultivation Program([2020]48)+2 种基金Institute of Technology of YF([2022]017)Guizhou Province High-Level Innovative Talents“Hundred”Level Talent Project(Qiankehe Platform Talent)GCC[2023]014Supported by the earmarked fund for GZMARS-Tea and Research on the Planting Technology of China HUANENG Photovoltaic Tea Garden(Project No.HNKJ2022-H135).
文摘The ATP-binding cassette(ABC)transporter is a gene superfamily in plants.ATP-binding cassette subfamily C(ABCC)protein is a multidrug resistance-associated(MRP)transporter.They play various roles in plant growth,development,and secondary metabolite transport.However,there are few studies on ABCC transporters in tea plants.In this study,genome-wide association study(GWAS)analysis of epigallocatechin gallate(EGCG)content in 108 strains of Kingbird revealed that CsABCCs may be involved in EGCG transport.We identified 25 CsABCC genes at the genomic level of the tea plant,their phylogenetic tree,gene structure,targeted miRNA and other bioinformatics were analyzed.The expression patterns of CsABCCs in eight different tissues and abiotic stress indicate that they have potential roles in regulating the growth,development,and defense of tea plants.The correlation analysis revealed that the expression of the CsABCC11 gene was closely related to the EGCG content in tea buds of 108 strains of the Kingbird,and the subcellular localization experiments in tobacco showed that CsABCC11 protein was localized on the plasma membrane.The virus-induced gene silencing(VIGS)strategy in tea plants further verified that CsABCC11 was involved in EGCG accumulation.Our study laid a foundation for studying the biological function of CsABCC and provided a new candidate molecular marker gene for further EGCG-related variety breeding,which will be of great interest to breeders.
基金supported by funds from the National Natural Science Foundation of China(31970363,31161140350)the Key Basic Research Program of Yunnan Province,China(202101BC070003)supported by the Scottish Government’s Rural and Environment Science and Analytical Services division。
文摘Chinese Assam tea(Camellia sinensis var.assamica)is an important tea crop with a long history of cultivation in Yunnan,China.Despite its potential value as a genetic resource,its genetic diversity and domestication/breeding history remain unclear.To address this issue,we genotyped 469 ancient tea plant trees representing 26 C.sinensis var.assamica populations,plus two of its wild relatives(six and three populations of C.taliensis and C.crassicolumna,respectively)using 16 nuclear microsatellite loci.Results showed that Chinese Assam tea has a relatively high,but comparatively lower gene diversity(H_(S)=0.638)than the wild relative C.crassicolumna(H_S=0.658).Clustering in STRUCTURE indicated that Chinese Assam tea and its two wild relatives formed distinct genetic groups,with considerable interspecific introgression.The Chinese Assam tea accessions clustered into three gene pools,corresponding well with their geographic distribution.However,New Hybrids analysis indicated that 68.48%of ancient Chinese Assam tea plants from Xishuangbanna were genetic intermediates between the Puer and Lincang gene pools.In addition,10%of the ancient Chinese Assam tea individuals were found to be hybrids between Chinese Assam tea and C.taliensis.Our results suggest that Chinese Assam tea was domesticated separately in three gene pools(Puer,Lincang and Xishuangbanna)in the Mekong River valley and that the hybrids were subsequently selected during the domestication process.Although the domestication history of Chinese Assam tea in southwestern Yunnan remains complex,our results will help to identify valuable genetic resources that may be useful in future tea breeding programs.
文摘This study investigates the nitrogen (N), phosphorous (P), and potassium (K) contents in raw biomasses of Camellia sinensis, Gliricidia sepium, and Musa acuminata. Therein, the highest N and P content was seen in Camellia sinensis 116.80 ± 0.08 mg and 66.00 ± 0.14 mg respectively. The highest K content (106.80 ± 0.04 mg) was observed in Musa acuminata. Next, all three types of plant materials were allowed to decompose in water for 3 weeks, and a sample from each was analyzed for NPK after the 1st, 2nd, and 3rd week during decomposition. A significant increase in the release of N, P, and K by the Camellia sinensis to water (P Musa acuminate were not significantly changed (P > 0.05) over time. The ratio for N:P:K was calculated for raw biomass samples and decomposed samples to find the best fitting N:P:K ratio to apply to young tea plants as organic fertilizers. In addition to that, the microbial insight of these organic compounds was analyzed by observing how microbial population increased with decomposition by the enumeration of the total microbial count. A considerable increment in total microbial count was observed up to 3.28 × 10<sup>6</sup>, 1.21 × 10<sup>10</sup>, 2.18 × 10<sup>8</sup>, and 6.49 × 10<sup>7</sup> CFU/ml for Camellia sinensis, Gliricidia sepium, Musa accuminata (leaves), and Musa accuminata (trunk) respectively. The presence of phosphate solubilizing bacteria (PSB) and nitrogen solubilizing bacteria (NSB) throughout the decomposition period was confirmed by their growth on NBRIP and a modified nutrient medium that was specifically designed for the identification of ammonifiers respectively. Prepared fertilizer samples were applied to young tea plants that were grown in the Mawanella area in Sri Lanka (7°15'12.42"N 80°26'47.62"E) and according to the results, it is clear that fertilizer mixture 1 (N:P:K, 10:5:10, tea dust + Gliricidia + banana trunk) and fertilizer mixture 2 (N:P:K, 10:5:10, tea dust + Gliricidia + banana leaves) has the potential to increase the growth of young tea plants.
基金the National Natural Science Foundation of China(32060349)China Scholarship Council([2021]15)。
文摘Seventeen morphological and anatomical characteristics of the leaves were selected from five natural populations to explore the variation in leaf traits of Lits ea core ana var.sinensis and the effects of geographical environment on these variations.Nested analysis of variance,multiple comparisons,principal component analysis(PCA),and correlation analysis were conducted to explore the variations within and between populations and their correlation with geographical and climatic factors.Significant differences in the 17 leaf traits were observed within and among populations.On average,the relative contribution of within population variation to total variation was 24.8%,which was lower than among population variation(54.6%).The average differentiation coefficient of the traits was 65.8%,and the average coefficient of variation 11.8%,ranging from6.7%for main vein thickness to 21.4%for petiole length.The PC A results showed that morphological characteristics were divided into two categories,and the level of variation was greater than that of leaf anatomy.Most of the leaf traits were significantly correlated with geography and climate and showed a gradual variation with longitude,latitude,and altitude.In areas with high temperatures,less rainfall,and strong seasonal rainfall,the leaves are larger,longer and thicker.This study shows that variations in leaf traits of L.coreana var.sinensis mainly come from variations among populations.The level of trait differentiation among populations is high and the level of variation within populations low.These findings help further understand leaf morphological characteristics of this species and can provide a valuable reference for the protection and sustainable utilization of this natural resource.
基金supported by the National Natural Science Foundation of China(Grant No.32170236 and 31501333)the Natural Science Foundation of Hebei Province(Grant No.C2020209064)+2 种基金the Project of Youth Fund for National Natural Science Foundation of China(Grant No.32001791)the Tangshan Science and Technology Planning Project(Grant No.20150209C)the innovation and entrepreneurship training program for college students of North China University of Science and Technology(Grant No.X2019256).
文摘Chinese mahogany(Toona sinensis) is of considerable medical and economic importance, and its genome has been deciphered. However, the process underlying its polyploidy is unclear, and the chromosomal evolutionary trajectory is poorly understood. Here, by reanalysing the T.sinensis genome, we found evidence of a tetraploidization event(T. sinensis special tetraploidization, TST) that occurred approximately 15-17 million years ago(MYA) after the core eudicot-common hexaploidization(ECH or gamma) event. We characterized the synonymous nucleotide substitution rates(Ks values) of collinear genes and found that T. sinensis genes affected by the TST evolve at a slower rate than Acer yangbiense genes. Furthermore, we identified homologous genes related to polyploidization and speciation and constructed multiple alignments with different reference genomes. Notably, the significant balance of gene retention and loss characterized in the two TST-derived subgenomes suggests an autopolyploid nature of the TST. Moreover, we deduced the chromosomal karyotypes of the two subgenomes and identified 7chromosomal fusions that have shaped the T. sinensis genome;more information is available on a newly constructed karyotype platform(http://www.cgrpoee.top/Toona_sinensis/index.html). The T. sinensis genome preserves the ancestral chromosome structure of dicotyledons well and could serve as a good reference for understanding genomic changes in other Meliaceae and Sapindales plants. In addition, we verified that tandem duplication and the ECH have promoted the expansion of terpene synthase(TPS) genes;conversely, the TST seems to have inhibited expansion of these genes. This present effort has clarified the polyploidy events of the T. sinensis genome, filled gaps in the history of karyotype evolution, and laid a solid foundation for further genomic studies in the Meliaceae research community and beyond.
文摘In this study, volatile compounds present in Toona sinensis (A. Juss.) Roem (TS) were investigated and their characteristic aromatic components were identified using Headspace Solid-phase Microextraction (HS-SPME) followed by Gas Chromatography-Mass Spectrometry (GC-MS) and Gas Chromatography-Olfactometry (GC-O). The optimum conditions for extracting the volatiles from TS were achieved with the experimental parameters including the use of a 65 μm polydimethylsiloxane/divinyl benzene (PDMS/DVB) fibre, an extraction temperature of 40℃ and an extraction time of 30 min. Under these conditions, 56 volatile compounds were separated and 53 were identified by GC-MS. Among them, 21 sulfide compounds (42.146%) and 27 terpenes(55.984%) were found to be the major components. The sample was analyzed by GC-O and 26 elutes were sniffed and their sensory descriptions evaluated by an odor panelists. Analysis of the data indicated, two compounds cis and trans isomers of 2-Mercapto-3,4-dimethyl-2,3-dihydrothiophene were major contributors to the characteristic aroma of TS.
基金supported by the Major Special Project of Scientific and Technological Innovation on Anxi Tea, China (AX2021001)the Fujian Agriculture and Forestry University Construction Project for Technological Innovation and Service System of Tea Industry Chain, China (K1520005A01)+1 种基金the earmarked fund for China Agriculture Research System (CARS-19)the fund for Excellent Master’s Dissertations of Fujian Agriculture and Forestry University, China (1122YS01007)。
文摘Various genetic and biochemical characteristics exist in tea plant cultivars,and they largely determine production suitability and tea quality.Here,we performed transcriptomic and metabolomic analyses of young shoots of seven tea cultivars and identified major regulatory transcription factors(TFs)for the characteristic metabolites in different cultivars based on weighted gene co-expression network analysis(WGCNA).Phenotypically,we found that‘Tieguanyin’(TGY)and‘Fujian Shuixian’(FJSX),which are suitable for oolong tea,had higher catechin contents.The metabolites of‘Jinxuan’(JX)were more prominent,especially the contents of phenolic acids,flavonoids,terpenes,and tannins,which were higher than those of the other six cultivars.Moreover,‘Fudingdabai’(FDDB),which is suitable for white tea,was rich in amino acids,linolenic acid,and saccharides.At the molecular level,hydroxycinnamoyl CoA quinate hydroxycinnamoyl transferase(HCT)(CsTGY12G0001876,and CsTGY06G0003042)led to the accumulation of chlorogenic acid in TGY.The main reason for the higher l-ascorbic acid content in FJSX was the high expression levels of L-galactono-1,4-lactone hydrogenase(GalLDH)(CsTGY13G0000389)and Myo-inositol oxygenase(MIOX)(CsTGY14G0001769,and CsTGY14G0001770),which were regulated by WRKY(CsTGY11G0001197).Furthermore,FDDB,‘Longjing 43’(LJ43),‘Shuchazao’(SCZ)and‘Baihaozao’(BHZ)had higher free fatty acid contents,among which MYB(CsTGY14G0002344)may be a hub gene for the regulation of palmitoleic acid accumulation.More importantly,we found that the shoots of TGY were green with purple,mainly due to the accumulation of anthocyanins and the downregulation of the Mg-protoporphyrin IX nonomethyl ester cyclase(MPEC)(CsTGY10G0001989)gene that affects chlorophyll synthesis.These results will provide a theoretical reference for tea cultivar breeding and suitability.
基金This study was funded by Shenzhen Science and Technology Program(Grant No.RCYX20210706092103024)Key-Area Research and Development Program of Guangdong Province(2020B020220004).
文摘Dear Editor,Tea plant(Camellia sinensis(L.)O.Kuntze)is one of the world’s most important non-alcoholic beverages,with great economic,health,and cultural value.Recently,several genomes of C.sinensis var.assamica(CSA)(Yunkang 10),C.sinensis var.sinensis(CSS)(Shuchazao,Biyun,Longjing 43,Tieguanyin,Huangdan),and ancient tea plant(DASZ)have been deciphered[1-3].
基金supported by the National Natural Science Foundation of China(81773844).
文摘Sesquiterpenes are the major pharmacodynamic components of agarwood,a precious traditional Chinese medicine obtained from the resinous portions of Aquilaria sinensis trees that form in response to environmental stressors.To characterize the sesquiterpene synthases responsible for sesquiterpene production in A.sinensis,a bioinformatics analysis of the genome of A.sinensis identifi ed six new terpene synthase genes,and 16 sesquiterpene synthase genes were identifi ed as type TPS-a in a phylogenetic analysis.The expression patterns for eight of the sesquiterpene synthase genes after treatment with various hormones or hydrogen peroxide were analyzed by real-time quantitative PCR.The results suggest that 100μM methyl jasmonate,ethephon,(±)-abscisic acid or hydrogen peroxide could be eff ective short-term eff ectors to increase the expression of sesquiterpene synthase genes,while 1 mM methyl salicylate may have long-term eff ects on increasing the expression of specifi c sesquiterpene synthase genes(e.g.,As-SesTPS,AsVS,AsTPS12 and AsTPS29).The expression changes in these genes under various conditions refl ected their specifi c roles during abiotic or biotic stresses.Heterologous expression of a novel A.sinensis sesquiterpene synthase gene,AsTPS2,in Escherichia coli produced a major humulene product,so AsTPS2 is renamed AsHS1.AsHS1 is diff erent from ASS1,AsSesTPS,and AsVS,for mainly producingα-humulene.Based on the predicted space conformation of the AsHS1 model,the small ligand molecule may bind to the free amino acid by hydrogen bonding for the catalytic function of the enzyme,while the substrate farnesyl diphosphate(FPP)probably binds to the free amino acid on one side of the RxR motif.Arg450,Asp453,Asp454,Thr457,and Glu461 from the NSE/DTE motif and D307 and D311 from the DDxxD motif were found to form a polar interaction with two Mg^(2+)clusters by docking.The Mg^(2+)-bound DDxxD and NSE/DTE motifs and the free RXR motif are jointly directed into the catalytic pocket of AsHS1.Comparison of the tertiary structural models of AsHS1 with ASS1 showed that they diff ered in structures in several positions,such as surrounding the secondary catalytic pocket,which may lead to diff erences in catalytic products.Based on the results,biosynthetic pathways for specifi c sesquiterpenes such asα-humulene in A.sinensis are proposed.This study provides novel insights into the functions of the sesquiterpene synthases of A.sinensis and enriches knowledge on agarwood formation.
基金Supported by the funding for school-level research projects of Yancheng Institute of Technology(No.xjr2019047)the National Natural Science Foundation of China(No.31902362)。
文摘The appropriate reference gene is a prerequisite for accurate normalization of gene expression level,and research on suitable reference genes in clam Cyclina sinensis is scarce.To improve the situation,we selected five commonly used housekeeping genes,including β-actin,Elongation factor 1-α(EF1-α),Glyceraldehyde-3-pho sphate dehydrogenase(GAPDH),40S ribosomal protein S18(RPS18),and Tubulin a(TUB-α),then evaluated their expression stability in different adult tissues and under different experimental treatments(salinity stress and Vibrio parahaemolyticus infection).Their expression stability was analyzed by three frequently used programs,geNorm,NormFinder,and BestKeeper.This analysis indicated that multiple genes should be used for normalization,and we concluded that the reference gene combination GAPDH-RPS18-β-actin,should be used for qRT-PCR analysis in different tissues of C.sinensis under normal physiological conditions.For the clams under salinity stress and Vibrio infection,EF1-α-GAPDHRPS18 was recommended as the gene combination for qRT-PCR normalization.TUB-αwas generally poorly ranked by all programs,and should not be used in future studies.This study should provide fundamental support for accurate quantitative gene expression analysis of this species.
基金jointly supported by the National Key Research and Development Program of China (Grant No. 2021YFD1000401)the National Natural Science Foundation of China (Grant No.32070376)+1 种基金the Program of Horticultural Crop Germplasm Resources in Hubei Province (Grant No. 2021DFE016)the Key Technology of Safety Production to Improve Tea Quality and Efficiency in Three Gorges Reservoir Area。
文摘Many attentions have been previously focused to identify the multiple biochemical components related to tea quality and health benefits,however, the natural variation of biochemical components present in tea germplasm has not been adequately evaluated. In this study, the main biochemical components, leaf morphological and yield characteristics were evaluated for four rounds of tea leaves in a panel of 87 elite tea cultivars suitable for black, green, or oolong tea. Significant variations were observed among the tea cultivars, as well as seasonal differences in the levels of the free amino acid(FAA), caffeine(CAF), tea polyphenols(TP), water extract(WE) and TP to FAA ratio(TP/FAA). Results showed that the average levels of FAA showed a seasonal change, with the highest level of 4.0% in the 1st spring tea in the cultivars suitable for green tea and the lowest of 3.2% in summer tea in the cultivars suitable for black tea. The average CAF content was highest 3.2% in the cultivars suitable for oolong tea in the 1st spring and the lowest 2.5% in the cultivars suitable for green tea in summer. Limited seasonal and varietal variations were noticed in the average levels of WE among the three categories of tea. In addition, significant natural variation of the morphological characteristics, bud length varying from 2.5 cm to 8.7 cm, bud density from 190.3 buds · m-2to 1 730.3 buds · m-2, mature leaves biomass from 128.4 kg · hm-2to 2 888.4 kg · hm-2, and yield component traits of 100 buds(one bud with two leaves) dry weight from 3.7 g to37.7 g, tea yield/round from 444.6 kg · hm-2to 905.3 kg · hm-2, were observed. The aim of our evaluation was not only to identify the advantages of seasonal and clonal variations but also to provide a new viewpoint for their further application. Representative accessions were selected from the germplasm to promote the establishment of an inherent biochemical constituent expressing the quality of black, green, and oolong tea. The findings might be utilized to establish early selection criteria to enhance the tea breeding and production program.
文摘We conducted experiments in an artificial stream tank with wild juvenile Chinese sturgeon Acipenser sinensis captured in the Yangtze Estuary to test the null hypothesis that their feeding efficiency on Barcheek goby Rhinogobius giurinus was not affected by sand vs. smooth glass substrate. Gobies are among the most common prey eaten by wild juvenile A. sinensis in the estuary. Test results found neither substrate type significantly affected feeding efficiency by juveniles. Previous research found a strong innate habitat preference of A. sinensis for sand substrate. The present results indicate that the preference for sand is not related to efficiently capturing R. giurinus on sand, but is an adaptation predisposing juvenile A. sinensis to seek sandy substrate where R. giurinus and other benthic forage are the most abundant in the Yangtze Estuary.
基金supported by the National Natural Science Foundation of China(32060349)China Scholarship Council([2021]15)。
文摘Studying the dynamics of plant populations is crucial to the conservation and management of endangered plants.The diameter at breast height(DBH),tree height,crown width,and environmental factors of a total of 15 plots in five populations in Guizhou Province,China were measured in this study.The method of substituting diameter at breast height for age was used to divide the population into 7 age classes.The age structure,static life table,and relationship between the population characteristics and environmental factors of the Litsea coreana Levl.var.sinensis population were studied.Moreover,the time series model was used to predict the population dynamics.Results showed that the age structure of population in Zhengan County(Population ZA)had an inverted Jshape with abundant seedlings and insufficient middle-aged and elderly individuals.The age structures of populations in Daozhen County(Population DZ),Kaiyang County(KY),Meitan County(Population MT),and Xishui County(Population XS)were spindle-shaped with few young individuals and many middle-aged and elderly individuals.The mortality rate of each population fluctuated with the increase in age class,and the populations were extremely unstable.The survival curve was close to the Deevey III type,and the degree of deviation was related to the lack of young individuals.After the age stages II,IV,and VI,the number of aged plants in the different populations initially increased then decreased,and population stability was difficult to maintain.Redundancy analysis showed that the DBH,tree height and crown width of the population decreased with the increase of annual mean temperature,and the population density was restricted by soil nutrient conditions to a certain extent.The results of this work provide scientific basis for the conservation and sustainable utilization of natural populations of L.coreana var.sinensis in Guizhou Province,China.
