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2.
Talanta ; 237: 122896, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34736712

RESUMO

Noroviruses are the leading cause of acute gastroenteritis and food-borne diseases worldwide. Thus, a rapid, accurate, and easy-to-implement detection method for controlling infection and monitoring progression is urgently needed. In this study, we constructed a novel sandwich-type electrochemical biosensor integrated with two specific recognition elements (aptamer and peptide) for human norovirus (HuNoV). The electrochemical biosensor was fabricated using magnetic covalent organic framework/pillararene heterosupramolecular nanocomposites (MB@Apt@WP5A@Au@COF@Fe3O4) as the signal probes. The sensor showed high accuracy and selectivity. The detection method does not need the extraction and amplification of virus nucleic acid and has a short turn-around time. Intriguingly, the proposed biosensor had a limit of detection of 0.84 copy mL-1 for HuNoV, which was the highest sensitivity among published assays. The proposed biosensor showed higher sensitivity and accuracy compared with immunochromatographic assay in the detection of 98 clinical specimens. The biosensor was capable of determining the predominant infection strain of GII.4 and also GII.3 and achieved 74% selectivity for HuNoV GII group. This study provides a potential method for point-of-care testing and highlights the integrated utilization of Apt and peptide in sensor construction.


Assuntos
Técnicas Biossensoriais , Estruturas Metalorgânicas , Nanocompostos , Norovirus , Humanos , Imunoensaio
3.
New Phytol ; 227(5): 1493-1504, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32343409

RESUMO

Local pathogens can accumulate as asymptomatic endophytes, making it difficult to detect the impacts of invasive species as propagators of disease in the invaded range. We used the invasive plant Ageratina adenophora to assess such accumulation. We intensively collected foliar fungal endophytes and leaf spot pathogens of A. adenophora and co-occurring neighbours and performed an inoculation experiment to evaluate their pathogenicity and host range. Ageratina adenophora harboured diverse necrotrophic pathogens; its communities of endophytes and leaf spot pathogens were different in composition and shared only a small number of fungal species. In the pathogen communities of local plant hosts, 21% of the operational taxonomic units (OTUs), representing 50% of strains, also occurred as leaf spot pathogens and/or endophytes of A. adenophora. The local pathogen community was more similar to the endophytes than to the pathogens of A. adenophora. The inoculation experiment showed that local pathogens could infect A. adenophora leaves asymptomatically and that local plant hosts were susceptible to both A. adenophora endophytes and pathogens. Ageratina adenophora is a highly competent host for local pathogens, and its asymptomatic latent pathogens are fungi primarily shared with local neighbours. This poses challenges for understanding the long-term ecological consequences of plant invasion.


Assuntos
Ageratina , Endófitos , Fungos , Espécies Introduzidas
4.
J Environ Sci (China) ; 88: 133-144, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31862055

RESUMO

Fe-Mn binary oxide (FMBO) possesses high efficiency for As(III) abatement based on the good adsorption affinity of iron oxide and the oxidizing capacity of Mn(IV), and the composition and structure of FMBO play important roles in this process. To compare the removal performance and determine the optimum formula for FMBO, magnetic graphene oxide (MRGO)-FMBO and MRGO-MnO2 were synthesized with MRGO as a carrier to improve the dispersity of the adsorbents in aquifers and achieve magnetic recycling. Results indicated that MRGO-FMBO had higher As(III) removal than that of MRGO-MnO2, although the ratios of Fe and Mn were similar, because the binary oxide of Fe and Mn facilitated electron transfer from Mn(IV) to As(III), while the separation of Mn and Fe on MRGO-MnO2 restricted the process. The optimal stoichiometry x for MRGO-FMBO (MnxFe3-xO4) was 0.46, and an extraordinary adsorption capacity of 24.38 mg/g for As(III) was achieved. MRGO-FMBO showed stable dispersive properties in aquifers, and exhibited excellent practicability and reusability, with a saturation magnetization of 7.6 emu/g and high conservation of magnetic properties after 5 cycles of regeneration and reuse. In addition, the presence of coexisting ions would not restrict the practical application of MRGO-FMBO in groundwater remediation. The redox reactions of As(III) and Mn(IV) on MRGO-FMBO were also described. The deprotonated aqueous As(III) on the surface of MRGO-FMBO transferred electrons to Mn(IV), and the formed As(V) oxyanions were bound to ferric oxide as inner-sphere complexes by coordinating their "-OH" groups with Mn(IV) oxides at the surface of MRGO-FMBO. This work could provide new insights into high-performance removal of As(III) in aquifers.


Assuntos
Arsênio/química , Recuperação e Remediação Ambiental/métodos , Grafite , Água Subterrânea , Poluentes Químicos da Água/química , Adsorção , Arsênio/análise , Compostos Férricos , Compostos de Manganês , Oxirredução , Óxidos , Poluentes Químicos da Água/análise
6.
Sci Rep ; 7(1): 1626, 2017 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-28487526

RESUMO

In the majority of sexual eukaryotes, the mitochondrial genomes are inherited uniparentally. As a result, individual organisms are homoplasmic, containing mitochondrial DNA (mtDNA) from a single parent. Here we analyzed the mitochondrial genotypes in Clade I of the gourmet mushroom Thelephora ganbajun from its broad geographic distribution range. A total of 299 isolates from 28 geographic locations were sequenced at three mitochondrial loci: the mitochondrial small ribosomal RNA gene, and the cytochrome c oxidase subunits I (COX1) and III (COX3) genes. Quantitative PCR analyses showed that the strains had about 60-160 copies of mitochondrial genomes per cell. Interestingly, while no evidence of heteroplasmy was found at the 12S rRNA gene, 262 of the 299 isolates had clear evidence of heterogeneity at either the COX1 (261 isolates) or COX3 (12 isolates) gene fragments. The COX1 heteroplasmy was characterized by two types of introns residing at different sites of the same region and at different frequencies among the isolates. Allelic association analyses of the observed mitochondrial polymorphic nucleotide sites suggest that mtDNA recombination is common in natural populations of this fungus. Our results contrast the prevailing view that heteroplasmy, if exists, is only transient in basidiomycete fungi.


Assuntos
Agaricales/genética , Genoma Mitocondrial , Recombinação Genética , Agaricales/isolamento & purificação , Sequência de Aminoácidos , Sequência de Bases , DNA Mitocondrial/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Amplificação de Genes , Loci Gênicos , Geografia , Heterozigoto , Homozigoto , Mitocôndrias/genética , Filogenia , RNA Ribossômico/genética , Análise de Sequência de DNA
7.
Hellenic J Cardiol ; 58(2): 124-132, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28179146

RESUMO

OBJECTIVE: This study was to determine whether different risk factors were associated with different type of left ventricular (LV) geometric abnormalities. METHODS: This retrospective analysis included 2290 hypertensive participants without other cardiovascular disease, valve disease and with ejection fraction ≥50%. The type of LV geometric abnormality was defined on the basis of the new classification system. RESULTS: LV geometric abnormalities were detected in 1479 subjects (64.6%), wherein concentric LV remodeling is the most common LV geometric abnormality (40.3%). Large waist circumference (WC) and neck circumference (NC) were positively associated with concentric LV remodeling, whereas body mass index (BMI) [odds ratio (OR) 0.89, 95% CI 0.85∼0.92, P < 0.001] and systolic blood pressure (SBP) (OR 0.99, 95% CI 0.98∼0.99, P = 0.018) were inversely associated with concentric abnormalities. SBP and age were positively associated with eccentric dilated LVH, while male was inversely associated with eccentric dilated left ventricular hypertrophy (LVH). Age was the strongest risk factor for eccentric dilated LVH (OR 1.05, 95% CI 1.03∼1.07, P < 0.001). Age, NC, SBP, hyperuricemia, and alcohol use were positively associated with concentric LVH, whereas BMI (OR 0.95, 95% CI 0.90∼0.99, P = 0.033) and male (OR 0.12, 95% CI 0.07∼0.18, P < 0.001) were negatively associated with concentric LVH. CONCLUSION: The prevalence of hypertensive LV geometric abnormality in rural area of Southern China was obvious higher. Compared with eccentric LV geometric abnormalities, there were more risk factors, including large WC and NC, age, NC, SBP, hyperuricemia, alcohol use, BMI and gender, which were associated with concentric LV geometric abnormalities.

8.
J Tradit Chin Med ; 37(2): 171-8, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-29960288

RESUMO

OBJECTIVE: To observe the effect of Tiaoshen Kaiqiao acupuncture in the treatment of ischemic post-stroke depression. METHODS: This research was a single-blind, positive-controlled trial done in a single entity. Totally 58 patients with ischemic post-stroke depression were randomly divided into two groups. The acupuncture group was given Tiaoshen Kaiqiao acupuncture therapy and placebo starch tablets treatment, while the control group was treated with fluoxetine tablets and body acupuncture treatment. Evaluated the clinical efficacy of the two groups with Hamilton Depression Scale (HAMD), Anti Depression Drug Side Effects Rating Scale (SERS), Clinical Global Impression Scale (CGI) respectively before treatment, the fourth weekend of treatment, the eighth weekend of treatment, the twelfth weekend of treatment. The adverse reactions in two groups were observed and documented. RESULTS: The HAMD scale scores of the two groups in different treatment period were significantly decreased compared with that before treatment (P < 0.05); the score reduction of HAMD scale between the two groups had no significant differences (P > 0.05). There was significant difference between the SERS scores of two groups (P < 0.05); the control group had more adverse reactions, and the score would be increased with the extension of treatment time. Effect index (EI) of CGI in the acupuncture group is better than that of control group (P < 0.05). CONCLUSION: The effects of Tiaoshen Kaiqiao acupuncture and fluoxetine in the treatment of ischemic post-stroke depression were similar, but the former had no obvious adverse reaction and side effects.


Assuntos
Terapia por Acupuntura , Depressão/terapia , Acidente Vascular Cerebral/complicações , Pontos de Acupuntura , Adulto , Idoso , Idoso de 80 Anos ou mais , Depressão/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Método Simples-Cego , Resultado do Tratamento
9.
Mitochondrial DNA B Resour ; 2(1): 103-105, 2017 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-33473731

RESUMO

The complete mitochondrial genome of the edible fungus Thelephora ganbajun was determined using Illumina sequencing. This mitogenome is a circular molecule of 52,857 bp in length with a GC content of 25.73%. Gene prediction showed that the mitogenome codes 28 tRNAs, 2 pseudo-tRNAs, and 21 known and 7 hypothetical proteins. The evolutionary relationships between Th. ganbajun and other representative species based on the mitogenome are consistent with those based on nuclear genes. The mitogenome information of Th. ganbajun should contribute to our understanding of the diversity and evolution of Thelephorales.

10.
BMC Complement Altern Med ; 16(1): 441, 2016 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-27821107

RESUMO

BACKGROUND: Acupuncture is beneficial for controlling chemotherapy-induced nausea and vomiting (CINV). However, the effect of different acupoint combinations on controlling CINV remains unknown. This study aims to compare the effects of distal-proximal point association and local distribution point association on controlling CINV. METHODS/DESIGN: The study is a single-center, randomized controlled trial. A total of 240 participants will be randomly divided into four groups. The control group will receive standard antiemetic only, whereas three acupuncture groups will receive four electro-acupuncture treatments once a day with the standard antiemetic. Acupuncture group I and II will receive distal-proximal point association ("Neiguan (PC6) and Zhongwan (CV12)", and "Zusanli (ST36) and CV12", respectively); Acupuncture group III will receive local distribution point association ("Shangwan (CV13) and CV12"). The primary outcome measures are the frequency and distress of nausea and vomiting. The secondary outcome measures are the grade of constipation and diarrhea, electrogastrogram, quality of life, etc. Assessment is scheduled from the day before chemotherapy to the fifth day of chemotherapy. Follow-ups are performed from the sixth day to the twenty-first day of chemotherapy. DISCUSSION: Results of this trial will help in evaluating the efficacy and safety of electro-acupuncture with different acupoint combinations in the management of CINV. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT02478047 .


Assuntos
Pontos de Acupuntura , Terapia por Acupuntura , Antineoplásicos/efeitos adversos , Náusea/terapia , Vômito/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/uso terapêutico , Protocolos Clínicos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Náusea/etiologia , Neoplasias/tratamento farmacológico , Vômito/etiologia , Adulto Jovem
11.
Materials (Basel) ; 9(3)2016 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-28773298

RESUMO

Recycling waste tire rubber by incorporating it into concrete has become the preferred solution to dispose of waste tires. In this study, the effect of the volume content of crumb rubber and pretreatment methods on the performances of concrete was evaluated. Firstly, the fine aggregate and mixture were partly replaced by crumb rubber to produce crumb rubber concrete. Secondly, the mechanical and durability properties of crumb rubber concrete with different replacement forms and volume contents had been investigated. Finally, the crumb rubber after pretreatment by six modifiers was introduced into the concrete mixture. Corresponding tests were conducted to verify the effectiveness of pretreatment methods as compared to the concrete containing untreated crumb rubber. It was observed that the mechanical strength of crumb rubber concrete was reduced, while durability was improved with the increasing of crumb rubber content. 20% replacement of fine aggregate and 5% replacement of the total mixture exhibited acceptable properties for practical applications. In addition, the results indicated that the modifiers had a positive impact on the mechanical and durability properties of crumb rubber concrete. It avoided the disadvantage of crumb rubber concrete having lower strength and provides a reference for the production of modified crumb rubber concrete.

12.
Acupunct Med ; 34(1): 33-9, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26177688

RESUMO

OBJECTIVE: The 'intensity-response' relationship between acupuncture stimulation and therapeutic effect is currently the focus of much research interest. The same needling manipulation with different frequencies can generate differential levels of stimulus. This study aimed to examine the effects on gastric motility induced by four twirling frequencies based on relatively standardised manual acupuncture (MA) manipulations. METHODS: Twirling manipulations at 1, 2, 3, and 4 Hz were practised before the experiments by a single operator using an MA parameter measurement device and stability was evaluated through time-frequency analysis. Forty-eight Sprague-Dawley rats were randomly divided into six groups (n=8 each): Control, Model, Model+MA (1, 2, 3, and 4 Hz). Rats in the five Model groups received injections of atropine into the tail vein to inhibit gastric motility, which was continuously recorded by a balloon in the gastric antrum. Rats in the four Model+MA groups received MA at 1, 2, 3 and 4 Hz, respectively, for 70 s and needles were retained for a further 5 min. RESULTS: The amplitude of waveforms produced by the four twirling frequencies was relatively consistent and reproducible. The gastric motility amplitude in all groups decreased after modelling (injections of atropine) (p<0.01). Twirling manipulation at 1, 2, and 3 Hz (but not 4 Hz) increased gastric motility amplitude (p<0.05). The increase in gastric motility amplitude induced by MA at 2 Hz was greater than for all other frequencies (p<0.05). CONCLUSIONS: Acupuncture at ST36 helped recover gastric motility amplitude in rats with atropine-induced gastric inhibition and the effects induced by 1-3 Hz frequency were greater than those induced by 4 Hz.


Assuntos
Pontos de Acupuntura , Terapia por Acupuntura , Atropina/farmacologia , Motilidade Gastrointestinal/efeitos dos fármacos , Estômago/fisiologia , Animais , Masculino , Ratos , Ratos Sprague-Dawley , Estômago/efeitos dos fármacos
15.
Mitochondrial DNA ; 26(6): 912-3, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-24409883

RESUMO

Pavo cristatus, known as the Indian peafowl, is endemic to India and Sri Lanka and has been domesticated for its ornamental and food value. However, its phylogenetic status is still debated. Here, to clarify the phylogenetic status of P. cristatus within Phasianidae, we analyzed its mitochondrial genome (mtDNA). The complete mitochondrial DNA (mtDNA) genome was determined using 34 pairs of primers. Our data show that the mtDNA genome of P. cristatus is 16,686 bp in length. Molecular phylogenetic analyses of P. cristatus was performed along with 22 complete mtDNA genomes belonging to other species in Phasianidae using Bayesian and maximum likelihood methods, where Aythya americana and Anas platyrhynchos were used as outgroups. Our results show that P. critatus has its closest genetic affinity with Pavo muticus and belongs to clade that contains Gallus, Bambusicola and Francolinus.


Assuntos
Galliformes/genética , Genoma Mitocondrial , Análise de Sequência de DNA/métodos , Animais , Tamanho do Genoma , Índia , Filogenia
16.
J Exp Child Psychol ; 112(4): 452-66, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22633135

RESUMO

Children with mathematics difficulties suffer from working memory deficits. This study investigated the deficit profile of phonological storage and executive functions in working memory among children with mathematics difficulties. Based on multiple instruments and two assessment points, 68 children were screened out of 805 fifth graders. Of these 68 children, 18 were classified as children with only mathematics difficulties (MD), 20 were classified as children with mathematics and reading difficulties (MDRD), and 30 were typically developing (TD) peers matched on age and general ability. Measures for phonological storage, dual-task performance, inhibition, and updating of verbal and numerical materials were administered individually. Results showed that compared with the TD group, children with MD exhibited storage and inhibition deficits specific to numerical information and dual-task deficits of both verbal and numerical information, whereas children with MDRD showed extensive deficits on phonological storage and executive functions on both verbal and numerical tasks. Moreover, executive function deficits were not confined to phonological storage deficits. Implications of the findings for the working memory deficit profile and working memory training among children with mathematics difficulties were discussed.


Assuntos
Função Executiva , Matemática , Fonética , Aptidão , Testes de Aptidão , Criança , Feminino , Humanos , Masculino , Matemática/educação , Memória de Curto Prazo , Resolução de Problemas
17.
Mycologia ; 102(6): 1318-38, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20943565

RESUMO

Colletotrichum interacts with numerous plant species overtly as symptomatic pathogens and cryptically as asymptomatic endophytes. It is not known whether these contrasting ecological modes are optional strategies expressed by individual Colletotrichum species or whether a species' ecology is explicitly pathogenic or endophytic. We explored this question by inferring relationships among 77 C. gloeosporioides s.l. strains isolated from asymptomatic leaves and from anthracnose lesions on leaves and fruits of Theobroma cacao (cacao) and other plants from Panamá. ITS and 5'-tef1 were used to assess diversity and to delineate operational taxonomic units for multilocus phylogenetic analysis. The ITS and 5'-tef1 screens concordantly resolved four strongly supported lineages, clades A-D: Clade A includes the ex type of C. gloeosporioides, clade B includes the ex type ITS sequence of C. boninense, and clades C and D are unidentified. The ITS yielded limited resolution and support within all clades, in particular the C. gloeosporioides clade (A), the focal lineage dealt with in this study. In contrast the 5'-tef1 screen differentiated nine distinctive haplotype subgroups within the C. gloeosporioides clade that were concordant with phylogenetic terminals resolved in a five-locus nuclear phylogeny. Among these were two phylogenetic species associated with symptomatic infections specific to either cacao or mango and five phylogenetic species isolated principally as asymptomatic infections from cacao and other plant hosts. We formally describe two new species, C. tropicale and C. ignotum, that are frequent asymptomatic associates of cacao and other Neotropical plant species, and epitypify C. theobromicola, which is associated with foliar and fruit anthracnose lesions of cacao. Asymptomatic Colletotrichum strains isolated from cacao plants grown in China included six distinct C. gloeosporioides clade taxa, only one of which is known to occur in the Neotropics.


Assuntos
Cacau/microbiologia , Colletotrichum/classificação , Colletotrichum/isolamento & purificação , Interações Hospedeiro-Patógeno , Filogenia , Simbiose , Cacau/fisiologia , Colletotrichum/genética , Colletotrichum/fisiologia , Dados de Sequência Molecular , Técnicas de Tipagem Micológica , Panamá
18.
J Hazard Mater ; 163(2-3): 869-73, 2009 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-18722054

RESUMO

A strain CSCr-3 with high Cr(VI)-reducing ability under alkaline conditions was isolated from a chromium landfill and identified as Ochrobactrum sp. on the basis of 16S rRNA gene sequence analysis. The cells were rod shaped, Gram-negative and motile. The physiological characteristics and Cr(VI)-reduction of the strain were also studied. The results showed that the Ochrobactrum sp. strain CSCr-3 was tolerant to very high concentration of Cr(VI) (800 mg/L) and capable of reducing different forms of Cr(VI) (chromate and dichromate), under a wide range of temperatures (25-40 degrees C) and pH (7-11) with optimum at 35 degrees C and initial pH 10. Higher rates of Cr(VI)-reduction were observed with higher initial cell and Cr(VI) concentrations. Strain CSCr-3 could reduce Cr(VI) very efficiently over a wide range of Cr(VI) concentrations (100-800 mg/L). The addition of glucose caused a dramatic increase in Cr(VI)-reduction by Ochrobactrum sp. CSCr-3, while the presence of sulfate or nitrate had no influence. The presence of other metals, such as Cu, Co, Mn, etc., significantly stimulated Cr(VI)-reduction ability by the strain CSCr-3. The results obtained in this study have significance for the bioremediation of chromate pollution.


Assuntos
Biodegradação Ambiental , Cromo/metabolismo , Ochrobactrum/isolamento & purificação , Poluentes Químicos da Água/metabolismo , Glucose , Concentração de Íons de Hidrogênio , Ochrobactrum/metabolismo , Oxirredução , Temperatura
19.
Microbiology (Reading) ; 154(Pt 11): 3460-3468, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18957599

RESUMO

The ectomycorrhizal fungus Thelephora ganbajun is an endemic gourmet mushroom in Yunnan province, south-western China. However, despite its widespread consumer appeal, nutritional value and potential ecological role in natural forests, very little is known about its genetics, diversity and ecology. In this study, we investigated DNA sequence variation at the internal transcribed spacer (ITS) regions among 156 specimens collected from 23 sites of nine regions in Yunnan Province. Our analysis identified a total of 34 ITS haplotypes and these haplotypes were clustered into five distinct phylogenetic groups. The evolutionary divergences among these clades are similar to or greater than many known sister species pairs within the genus Thelephora and the closely related genus Tomentella. Among the 34 ITS haplotypes, 22 were represented by one specimen each and the remaining 12 were each shared by two or more specimens. The most common haplotype contained 68 specimens distributed in 21 of the 23 sites, a result consistent with gene flow among geographical populations. However, analysis of molecular variance (AMOVA) revealed low but significant genetic differentiation among local and regional populations. Interestingly, the Mantel test identified that the extent of genetic differentiation was not significantly correlated with geographical distance. Our study revealed significant genetic divergence within Th. ganbajun and limited but detectable gene flow among geographical populations of this endemic ectomycorrhizal gourmet mushroom.


Assuntos
Agaricales/genética , Agaricales/metabolismo , Variação Genética , Agaricales/classificação , Agaricales/isolamento & purificação , China , DNA Intergênico/genética , Haplótipos , Filogenia , Pinus/microbiologia , Análise de Sequência de DNA
20.
Mol Ecol ; 17(5): 1238-47, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18302686

RESUMO

Effective conservation and utilization strategies for natural biological resources require a clear understanding of the natural populations of the target organisms. Tricholoma matsutake is an ectomycorrhizal mushroom that forms symbiotic associations with plants and plays an important ecological role in natural forest ecosystems in many parts of the world. It is also an economically very important gourmet mushroom. Because no artificial cultivation is available, natural populations of this species are under increasing threats, primarily from habitat disturbance and destruction. Despite its economical and ecological importance, little is known about its genetics and population biology. Here, using 14 polymerase chain reaction-restriction fragment length polymorphism markers, we analysed 154 strains from 17 geographical locations in southwestern China, a region where over 25% of the global T. matsutake harvest comes from. Our results revealed abundant genetic variation within individual populations. The analyses of gene and genotype frequencies within populations indicated that most loci did not deviate from Hardy-Weinberg equilibrium in most populations and that alleles among loci were in linkage equilibrium in the majority of the local populations. These results are consistent with the hypothesis that sexual reproduction and recombination play an important role in natural populations of this species. Our analyses indicated low but significant genetic differentiation among the geographical populations, with a significant positive correlation between genetic distance and geographical distance. We discuss the implications of our results to the ecology and resource management of this species.


Assuntos
Agaricales/genética , Micorrizas/genética , Recombinação Genética/genética , China , Variação Genética , Genótipo , Geografia , Dinâmica Populacional
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