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1.
Plant Dis ; 108(6): 1659-1669, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38128078

RESUMO

Wheat stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most destructive diseases worldwide. In China, wheat stripe rust generally occurs in the northwestern and southwestern regions; however, the genetic relationships of Pst populations between these regions are largely unclear. To determine the population structure and potential migration route in these regions, 235 isolates collected from Xinjiang (XJ), Gansu (GS), Ningxia (NX), Shaanxi (SX), Sichuan (SC), and Yunnan (YN) provinces in 2021 and 2022 were phenotyped using two sets of Pst differentials and genotyped using 20 competitive allele-specific PCR-single nucleotide polymorphism (KASP-SNP) markers. The phenotype tests indicated that CYR34, CYR32, and CYR33 were the predominant races with different occurrence frequencies in different regions and years. Genotypic analysis revealed that a total of 183 multilocus genotypes were identified, and the genetic diversity in the YN subpopulation was the highest. The genetic background in the SX subpopulation was similar to that in the GS and NX subpopulations, and the genetic background in the YN subpopulation was similar to that in the SC and SX subpopulations. A high level of gene flow (Nm) was found between the SX and GS, SX and NX, GS and NX, and SC and YN subpopulations, suggesting the migration of Pst among these regions, while a small amount of Nm existed between the SX and SC subpopulations. SC may serve as a bridge connecting Pst subpopulations between the northwestern provinces (SX, GS, and NX) and the southwestern provinces (SC and YN). With a relatively high genetic distance and low Nm values compared with other Pst subpopulations, XJ is considered a relatively independent epidemiological region in China. These results improved our current understanding of the wheat stripe rust epidemic in northwestern and southwestern regions of China.


Assuntos
Genótipo , Doenças das Plantas , Puccinia , Triticum , China , Triticum/microbiologia , Doenças das Plantas/microbiologia , Puccinia/genética , Polimorfismo de Nucleotídeo Único/genética , Fenótipo , Variação Genética , Filogenia
2.
New Phytol ; 237(6): 2467-2477, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36478218

RESUMO

Buckwheat is an important crop which originated in China and spread widely across Eurasia. However, exactly where in China domestication took place remains controversial. Archaeological and palynological records suggest a longer cultivation history of buckwheat in northern China than in southwestern China, but this conflicts with phylogenetic evidence implicating southwestern China as the centre of origin and diversity of buckwheat. We investigate alternative methodologies for inferring the occurrence of buckwheat cultivation and suggest that relative abundance could provide a reliable measure for distinguishing between wild and cultivated buckwheat in both present-day and fossil samples. Approximately 12 800-yr palaeoecological record shows that Fagopyrum pollen occurred only infrequently before the early Holocene. As southwestern China entered the early agricultural period, c. 8000-7000 yr ago, a slight increase in abundance of Fagopyrum pollen was observed. Approximately 4000 yr ago, concurrent with the Pu minority beginning to develop dry-land agriculture, the abundance of Fagopyrum pollen increased significantly, suggesting the cultivation of this crop. Fagopyrum pollen rose to a maximum value c. 1270 yr ago, suggesting an intensification of agricultural activity. These findings fill a gap in the Fagopyrum pollen record in southwestern China and provide new indications that early cultivation may have occurred in this region.


Assuntos
Fagopyrum , Filogenia , China , Agricultura , Pólen
3.
Eur J Clin Microbiol Infect Dis ; 42(1): 113-120, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36413338

RESUMO

We describe the opportunistic infections (OIs) of HIV/AIDS to understand the spectrum, mortality, and frequency of multiple coinfected OIs among HIV/AIDS patients in southern China, where OIs are severe. We carried out a retrospective cohort study of hospitalized HIV-infected individuals at the Fourth People's Hospital of Nanning, Guangxi, China, from Jan. 2011 to May. 2019. The chi-square test was used to analyze cross-infection; the Kaplan‒Meier analysis was used to compare mortality. A total of 12,612 HIV-infected patients were admitted to this cohort study. Among them, 8982 (71.2%) developed one or more OIs. The overall in-hospital mortality rate was 9.0%. Among the patients, 35.6% coinfected one OI, and 64.4% coinfected more than two OIs simultaneously. Almost half of the patients (60.6%) had CD4 + T-cell counts < 200 cells/µL. Pneumonia (39.8%), tuberculosis (35.3%), and candidiasis (28.8%) were the most common OIs. Coinfected cryptococcal meningitis and dermatitis are the most common combined OIs. The rate of anaemia (17.0%) was highest among those common HIV-associated complications. Multiple OIs are commonly found in hospitalized HIV/AIDS patients in southwestern China, which highlights the need for improved diagnosis and treatment.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS , Síndrome da Imunodeficiência Adquirida , Coinfecção , Infecções por HIV , Humanos , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Infecções por HIV/diagnóstico , Infecções Oportunistas Relacionadas com a AIDS/epidemiologia , Infecções Oportunistas Relacionadas com a AIDS/diagnóstico , Estudos de Coortes , Estudos Retrospectivos , China/epidemiologia , Síndrome da Imunodeficiência Adquirida/complicações , Coinfecção/epidemiologia , Coinfecção/complicações , Contagem de Linfócito CD4
4.
Mol Phylogenet Evol ; 177: 107619, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36007821

RESUMO

The striped-back shrew group demonstrates remarkable variation in skull and body size, tail length, and brightness of the dorsal stripe; and karyotypic and DNA variation has been reported in recent years. In this study, we investigated the phylogenetic structure of the group, as well as speciation patterns and demographic history in Mountains of Southwestern China and adjacent mountains, including the southern Himalayas, Mts. Bashan, Wushan, and Qinling. We sequenced a total of 462 specimens from 126 localities in the known range of the group, which were sequenced and analyzed based on 6.2 kb of sequence data from two mitochondrial, six nuclear, and two Y chromosome markers. Phylogenetic analyses of the concatenated mtDNA data revealed 14 sympatric and independently evolving lineages within the striped-back shrew group, including Sorex bedfordiae, S. cylindricauda, S. excelsus, S. sinalis and several cryptic species. All concatenated data (ten genes) showed a consistent genetic structure compared to the mtDNA lineages for the group, whereas the nuclear and the Y chromosome data showed a discordant genetic structure compared to the mtDNA lineages for the striped-back shrew group. Species delimitation analyses and deep genetic distance clearly support the species status of the 14 evolving lineages. The divergence time estimation suggested that the striped-back shrew group began to diversify from the middle Pleistocene (2.34 Ma), then flourished at approximately 2.14 Ma, followed by a series of rapid diversifications through the Pleistocene. Our results also revealed multiple mechanisms of speciation in the Mountains of Southwestern China and Adjacent Mountains with complex landscapes and climate. The uplifting of the Qinghai-Tibetan Plateau, Quaternary climate oscillations, riverine barriers, ecological elevation gradients, topographical diversity, and their own low dispersal capacity may have driven the speciation, genetic structure, and phylogeographic patterns of the striped-back shrew group.


Assuntos
Eulipotyphla , Musaranhos , Animais , DNA Mitocondrial/genética , Marcadores Genéticos , Variação Genética , Filogenia , Musaranhos/genética
5.
Microb Pathog ; 158: 105025, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34090984

RESUMO

Yunling cattle is an unique cattle breed distributed in Yunnan Province, southwestern China. It is yet to know whether Yunling cattle are infected with Giardia duodenalis and Cryptosporidium spp.. The objectives of the present study were to investigate the prevalence and characterize the assemblages of G. duodenalis and species of Cryptosporidium spp. in Yunling cattle in Yunnan province. The overall prevalence of G. duodenalis and Cryptosporidium spp. were 10.49% (41/391) and 0.77% (3/391), respectively. The age was considered as the risk factor for Yunling cattle infection with G. duodenalis (χ2 = 8.082, OR = 2.56, P = 0.004). Two assemblages of G. duodenalis, assemblage A (n = 1) and assemblage E (n = 40), were identified by amplification of the ß-giardin (bg) and glutamate dehydrogenase (gdh) gene loci using the nested PCR methods. Furthermore, Cryptosporidium andersoni (n = 1) and Cryptosporidium ryanae (n = 2) were detected by nested PCR targeting the small subunit (SSU) rRNA gene. This is the first report of G. duodenalis and Cryptosporidium spp. in Yunling cattle in China, which provided baseline date for further studies of the prevalence, genetic identity, and public health potential of these parasites in Yunling cattle.


Assuntos
Criptosporidiose , Cryptosporidium , Giardia lamblia , Giardíase , Animais , Bovinos , China/epidemiologia , Criptosporidiose/epidemiologia , Cryptosporidium/genética , Fezes , Genótipo , Giardia lamblia/genética , Giardíase/epidemiologia , Giardíase/veterinária , Prevalência
6.
Environ Res ; 201: 111537, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34166667

RESUMO

Nitrate (NO3-) is one of the most important inorganic ions in fine particulate (PM2.5) and drives regional haze formation; however, the NO3- sources and formation mechanisms in different seasons and regions are still debated. Here, PM2.5 samples were collected from Kunming and Nanning in southwestern China from September 1, 2017, to February 28, 2018 (spanning warm and cold months). We measured the daily O and N isotopic compositions of NO3- (δ18O-NO3- and δ15N-NO3-), estimated the δ18O-HNO3 values produced by different oxidation pathways, and quantified the NO3- formation pathways based on the isotope mass-balance equation. Our results showed that the δ18O-NO3- values in Kunming (65.3 ± 7.6‰) and Nanning (67.7 ± 10.1‰) are close to the δ18O-HNO3 values arising from the OH radical pathway (POH, 54.7 ± 1.2‰ to 61.2 ± 1.8‰), suggesting that the δ18O-NO3- values are mainly influenced by POH, which showed a contribution greater than 74%. Stronger surface solar radiation and higher air temperatures in low-latitude regions and warm months increased the amount of HNO3 produced by POH and reduced the amount of HNO3 produced by PN2O5, which produced low δ18O-NO3- values. Increased air pollution emissions decreased the contribution from POH and increased the contribution from N2O5 and NO3 pathways (PN2O5+NO3). The δ15N-NO3- values of PM2.5 in Kunming (7.3 ± 2.8‰) were slightly higher than those in Nanning (2.8 ± 2.7‰). The increased NOx emissions with positive isotopic values led to high δ15N-NO3- values in northern China and during cold months. A higher fNO2 (fNO2 = NO2/(NO + NO2), temperature, and contribution of POH produced lower N isotope fractionation between NOx and δ15N-NO3-, which was found to further decrease the δ15N-NO3- values in southwestern China and during warm months.


Assuntos
Nitratos , Oxigênio , China , Monitoramento Ambiental , Nitratos/análise , Isótopos de Nitrogênio/análise , Estações do Ano
7.
Int J Legal Med ; 134(3): 987-988, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31729603

RESUMO

The Blang is a minority living in the mountainous areas of Xishuangbanna Dai Autonomous Prefecture, and they also scatter in the neighboring cities of Lincang and Simao. This population is investigated in this study through PowerPlex® 21 System. The frequency distribution of allele, forensic, and population parameters of 20 autosomal short tandem repeat loci were evaluated based on 207 non-related individuals from Blang minority; meanwhile, the genetic relationships between Blang and 11 related populations were also assessed.


Assuntos
Etnicidade/genética , Frequência do Gene , Repetições de Microssatélites , Povo Asiático/genética , China/etnologia , Genética Populacional , Humanos
8.
Conserv Biol ; 34(5): 1142-1151, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-31994789

RESUMO

Reviews that summarize the genetic diversity of plant species in relation to their life history and ecological traits show that forest trees have more genetic diversity at population and species levels than annuals or herbaceous perennials. In addition, among-population genetic differentiation is significantly lower in trees than in most herbaceous perennials and annuals. Possible reasons for these differences between trees and herbaceous perennials and annuals have not been discussed critically. Several traits, such as high rates of outcrossing, long-distance pollen and seed dispersal, large effective population sizes (Ne ), arborescent stature, low population density, longevity, overlapping generations, and occurrence in late successional communities, may make trees less sensitive to genetic bottlenecks and more resistant to habitat fragmentation or climate change. We recommend that guidelines for genetic conservation strategies be designed differently for tree species versus other types of plant species. Because most tree species fit an LH scenario (low [L] genetic differentiation and high [H] genetic diversity), tree seeds could be sourced from a few populations distributed across the species' range. For the in situ conservation of trees, translocation is a viable option to increase Ne . In contrast, rare herbaceous understory species are frequently HL (high differentiation and low diversity) species. Under the HL scenario, seeds should be taken from many populations with high genetic diversity. In situ conservation efforts for herbaceous plants should focus on protecting habitats because the typically small populations of these species are vulnerable to the loss of genetic diversity. The robust allozyme genetic diversity databases could be used to develop conservation strategies for species lacking genetic information. As a case study of reforestation with several tree species in denuded areas on the Korean Peninsula, we recommend the selection of local genotypes as suitable sources to prevent adverse effects and to insure the successful restoration in the long term.


Incorporación de diferencias de diversidad genética entre árboles y plantas herbáceas en estrategias de conservación Resumen Las revisiones que resumen la diversidad genética de las plantas en relación con sus características ecológicas y biológicas muestran que los árboles forestales tienen más diversidad genética a nivel de población y de especie que las plantas anuales o las perennes herbáceas. Sumado a esto, la diferenciación genética entre poblaciones es significativamente más baja en los árboles que en la mayoría de las perennes herbáceas y las anuales. Hasta la fecha no se han discutido críticamente las posibles explicaciones de estas diferencias entre los árboles y las perennes herbáceas y las plantas anuales. Varias características, como las tasas altas de alogamia, la dispersión a gran distancia de polen y semillas, el gran tamaño de la población efectiva (Ne ), la estatura arbórea, la baja densidad poblacional, la longevidad, el solapamiento de generaciones y la presencia dentro de comunidades sucesionales tardías, pueden generar en los árboles una menor sensibilidad a los cuellos de botella genéticos y una mayor resistencia a la fragmentación del hábitat o al cambio climático. Recomendamos que las directrices para las estrategias de conservación genética estén diseñadas de manera diferente para las especies arbóreas que para otro tipo de plantas. Ya que la mayoría de las especies arbóreas encajan dentro de un escenario LH (baja [L] diferenciación genética y alta [H] diversidad genética), las semillas de los árboles podrían tomarse de unas cuantas poblaciones dispersas a lo largo del área de distribución de la especie. Por lo anterior, para la conservación in situ de los árboles, la translocación es una opción viable para incrementar la Ne . Al contrario de esta situación, las especies herbáceas raras del sotobosque con frecuencia son especies HL (alta diferenciación y baja diversidad). En el escenario HL, las semillas deberían ser recolectadas de muchas poblaciones con diversidad genética alta y los esfuerzos de conservación in situ para las plantas herbáceas deberían enfocarse en la protección del hábitat ya que las poblaciones típicamente pequeñas de estas especies son vulnerables a la pérdida de la diversidad genética. Las robustas bases de datos de diversidad genética aloenzimática podrían usarse para desarrollar estrategias de conservación para las especies que carecen de información genética. Como caso de estudio de reforestación con varias especies arbóreas en áreas deforestadas de la Península de Corea, recomendamos la selección de genotipos locales como fuente adecuada para prevenir los efectos adversos y para asegurar la restauración exitosa a largo plazo.


Assuntos
Conservação dos Recursos Naturais , Árvores , Ecossistema , Variação Genética , Plantas , Árvores/genética
9.
Mol Biol Rep ; 47(10): 7755-7760, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32989501

RESUMO

In this study, we have analyzed 23 Y-chromosomal short tandem repeats (Y-STRs) (DYS576, DYS389I, DYS389II, DYS448, DYS19, DYS391, DYS481, DYS549, DYS533, DYS438, DYS437, DYS570, DYS635, DYS390, DYS439, DYS392, DYS643, DYS393, DYS458, DYS460, DYS385ab, DYS456 and Y-GATA-H4) in 175 father-son sample pairs using a Microreader™ 24Y Direct ID system. Sixteen repeat mutations of father-son pairs at 10 loci, including three mutations at DYS570, 2 mutations at DYS549, DYS460, DYS458, and DYS576, and 1 mutation at other five loci, were revealed. Furthermore, all of the observed repeat mutations were single repeat changes with 5 (31.25%) repeat insertions and 11 (68.75%) repeat deletions. The deletion rate is more than two fold higher than of insertions (11:5 = 2.2-fold). Locus-specific mutation rates estimated varied between 5.71 × 10-3 (CI from 0.1 × 10-3 to 31.4 × 10-3) and 1.71 × 10-2 (CI from 3.6 × 10-3 to 49.3 × 10-3) for the 23 Y-STRs. An average mutation rate across all 23 Y-STR markers was estimated as 3.97 × 10-3 (CI 2.3 × 10-3 to 6.4 × 10-3). Thus, locus-specific mutation rates in DYS460, DYS458, and DYS438, estimated are much higher than previously published comprehensive data, but an average mutation rate across all 23 Y-STR markers is similar to previous reports (3.97 × 10-3 vs 4.34 × 10-3). These results by characterizing Y-STR mutations will not only provided new information for Y-STR mutations but also might be important for paternal lineage identification, kinship analysis, and family relationship reconstruction in our forensic Y-STR analysis.


Assuntos
Povo Asiático/genética , Cromossomos Humanos Y/genética , Repetições de Microssatélites , Mutação , China , Pai , Humanos , Masculino
10.
BMC Infect Dis ; 19(1): 89, 2019 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-30683067

RESUMO

BACKGROUND: Seasonal patterns of influenza A subtypes and B lineages in tropical/subtropical regions across age have remained to be explored. The impact of the 2009 H1N1 pandemic on seasonal influenza activity have not been well understood. METHODS: Based on a national sentinel hospital-based influenza surveillance system, the epidemiology of influenza virus during 2006/07-2015/16 was characterized in the subtropical city, Chengdu. Chengdu is one of the most populous cities in southwestern China, where the first reported case of A/H1N1pdm09 in mainland China was identified. Wavelet analysis was applied to identify the periodicities of A/H3N2, seasonal A/H1N1, A/H1N1pdm09, Victoria, and Yamagata across age, respectively. The persistence and age distribution patterns were described during the pre-pandemic (2006/07-2008/09), pandemic (2009/10), and post-pandemic (2010/11-2015/16) seasons. RESULTS: A total of 10,981 respiratory specimens were collected, of which 2516 influenza cases were identified. Periodicity transition from semi-annual cycles to an annual cycle was observed for composite influenza virus as well as A/H3N2 along in Chengdu since the 2009 H1N1 pandemic. Semi-annual cycles of composite influenza virus and A/H3N2 along were observed again during 2014/15-2015/16, coinciding with the emergence and predominance of A/H3N2 significant antigenic drift groups. However, A/H1N1pdm09, Victoria, and Yamagata generally demonstrated an annual winter-spring peak in non-pandemic seasons. Along with periodicity transitions, age groups with higher positive rates shifted from school-aged children and adults to adults and the elderly for A/H1N1pdm09 during 2009/10-2010/11 and for A/H3N2 during 2014/15-2015/16. CONCLUSIONS: Differences in periodicity and age distribution by subtype/lineage and by season highlight the importance of increasing year-round influenza surveillance and developing subtype/lineage- and age-specific prevention and control measures. Changes of periodicity and age shifts should be considered in public health response to influenza pandemics and epidemics. In addition, it is suggested to use quadrivalent influenza vaccines to provide protection against both influenza B lineages.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Vírus da Influenza A Subtipo H3N2 , Influenza Humana/virologia , Pandemias , Adolescente , Adulto , Distribuição por Idade , Idoso , Criança , Pré-Escolar , China/epidemiologia , Cidades , Feminino , Hospitais , Humanos , Lactente , Recém-Nascido , Vírus da Influenza A Subtipo H1N1/imunologia , Vírus da Influenza A Subtipo H3N2/imunologia , Influenza Humana/epidemiologia , Masculino , Pessoa de Meia-Idade , Estações do Ano , Vigilância de Evento Sentinela , Adulto Jovem
11.
AIDS Res Ther ; 16(1): 6, 2019 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-30876476

RESUMO

OBJECTIVE: This study aimed to investigate the prevalence of HIV late presentation and advanced HIV disease and to identify the factors associated with HIV late presentation and advanced HIV disease among patients with newly diagnosed HIV/AIDS in the Guangxi Zhuang Autonomous Region, in Southwestern China. METHODS: Patients with newly diagnosed HIV registered in the HIV surveillance system of Guangxi Centers for Disease Control between January 2012 and December 2016 were included in this study. RESULTS: Of 45,118 newly diagnosed patients, 70.2% had late presentation, and 45.1% had advanced HIV disease. A higher prevalence of late presentation and advanced HIV disease was found in male heterosexuals and female people who use drugs (PWID). Heterosexuals (OR 2.11 [95% CI 1.90-2.34]) and PWID (OR 1.55 [95% CI 1.30-1.84]) had a higher risk of late presentation than men who have sex with men (MSM). Blood testing of the blood receivers (OR 1.75 [95% CI 1.36-2.26]) and diagnosed in hospital (OR 1.74 [95% CI 1.65-1.84]) had an increased risk of late presentation compared to those who diagnosis in voluntary counseling and testing (VCT). Heterosexuals (OR 2.86 [95% CI 2.51-3.27]), PWID (OR 2.23 [95% CI 1.83-2.71]), blood testing of the blood receivers (OR 1.58 [95% CI 1.29-1.94]) and diagnosed in hospital (OR 1.85 [95% CI 1.76-1.94]) were also independent risk factors associated with advanced HIV disease. Older age, lower level of education and being divorced or widowed were also associated with late presentation and advanced HIV disease. CONCLUSIONS: Late presentation and advanced HIV disease were very common among patients with newly diagnosed HIV in Guangxi, China during 2012-2016. Targeted programs are urgently required to reduce HIV late diagnosis in Guangxi, especially for male heterosexuals, PWID, and patients with characteristics such as older age, lower level of education, divorced or widowed.


Assuntos
Diagnóstico Tardio , Monitoramento Epidemiológico , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Adolescente , Adulto , Fatores Etários , China/epidemiologia , Aconselhamento , Estudos Transversais , Usuários de Drogas , Feminino , Heterossexualidade , Homossexualidade Masculina , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Minorias Sexuais e de Gênero , Adulto Jovem
12.
Turk J Med Sci ; 47(5): 1456-1462, 2017 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-29151317

RESUMO

Background/aim: Helicobacter pylori (H. pylori) has a high prevalence in developing countries. We aimed to investigate the current prevalence of H. pylori, as well as its potential serum risk factors, in a population from southwest China.Materials and methods: This cross-sectional study included 10,912 subjects who received medical examinations at the First Affiliated Hospital of Chongqing Medical University in 2014. Data regarding physical examinations and biochemical measurements were collected, and H. pylori infection was diagnosed with a 13C-urea breath test. Logistic regression was conducted to identify the risk factors for H. pylori infection.Results: The infection rate of H. pylori was 34.4% (3750/10,912). Older age, lower albumin levels, and higher total cholesterol, LDL-cholesterol, and fasting blood sugar were significantly associated with increased incidence of H. pylori infection. Moreover, logistic regression analysis showed that older age, low albumin, and hyperglycemia were independent risk factors for H. pylori infection after adjusting for other covariables.Conclusion: The results from our study showed that H. pylori was prevalent in southwest China. Older age, low albumin levels, and hyperglycemia were significant risk factors associated with H. pylori infection.

13.
J Plant Res ; 129(2): 209-23, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26691316

RESUMO

Interpretation of the biogeography of the genus Mahonia (Berberidaceae) is limited by the lack of fossil records in East Asia. Compressed fossil foliage, described here as Mahonia mioasiatica sp. nov., were collected from the Upper Miocene Xiaolongtan Formation in Wenshan, Yunnan, southwest China. These specimens represent the oldest reliable fossil record of Mahonia in East Asia. This new fossil species shows a general similarity to Group Orientales and is most similar to the extant eastern Asian Mahonia conferta. Considering other fossil evidence of Mahonia, we propose a migration route of this genus to Asia over the North Atlantic Land Bridge rather than the Bering Land Bridge. Our results also suggest that North America, Europe and East Asia have been successive centers of diversity for the genus, as a consequence of diversification in Group Orientales potentially related to historical climate change.


Assuntos
Mahonia/anatomia & histologia , China , Mudança Climática , Fósseis , Geografia , Mahonia/genética , Filogeografia , Dispersão Vegetal , Folhas de Planta/anatomia & histologia , Folhas de Planta/genética
14.
Am J Bot ; 101(10): 1700-10, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25326615

RESUMO

An increasing global demand for food, coupled with the widespread decline of pollinator diversity, remains an international concern in agriculture and genetic conservation. In particular, there are large gaps in the study of the pollination of economically important and traditionally grown species in China. Many plant species grown in China are both edible and used medicinally. The country retains extensive written records of agricultural and apicultural practices, facilitating contemporary studies of some important taxa. Here, we focus on Yunnan in southwestern China, a mega-biodiversity hotspot for medicinal/food plants. We used plant and insect taxa as model systems to understand the patterns and consequences of pollinator deficit to crops. We identified several gaps and limitations in research on the pollination ecology and breeding systems of domesticated taxa and their wild relatives in Yunnan and asked the following questions: (1) What is known about pollination systems of edible and medicinal plants in Yunnan? (2) What are the most important pollinators of Codonopsis subglobosa (Campanulaceae)? (3) How important are native pollinator species for maximizing yield in Chinese crops compared with the introduced Apis mellifera? We found that some crops that require cross-pollination now depend exclusively on hand pollination. Three domesticated crops are dependent primarily on the native but semidomesticated Apis cerana and the introduced A. mellifera. Other species of wild pollinators often play important roles for certain specialty crops (e.g., Vespa velutina pollinates Codonopsis subglobosa). We propose a more systematic and comprehensive approach to applied research in the future.


Assuntos
Agricultura , Abelhas , Cruzamento , Produtos Agrícolas/genética , Variação Genética , Plantas Medicinais/genética , Polinização , Animais , Biodiversidade , China , Codonopsis , Ecologia , Plantas Medicinais/metabolismo , Especificidade da Espécie , Vespas
15.
Zookeys ; 1192: 141-178, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38425441

RESUMO

Ten new species of jumping spiders are described from China, including Attulusjimanisp. nov. (♂♀) from Yunnan, Colaxescibagousp. nov. (♂♀), Epeuspengisp. nov. (♂♀), Evarchazayusp. nov. (♂♀), Iciuszangsp. nov. (♂♀), Pancoriusnyingchisp. nov. (♂♀), Stertiniusliqingaesp. nov. (♂♀), and Synagelidesmedogsp. nov. (♀) from Xizang, S.tianquansp. nov. (♂♀), and Yaginumaellaerlangsp. nov. (♂♀) from Sichuan. The hitherto unknown female of Phintellalongapophysis Lei & Peng, 2013 is described for the first time. Diagnostic photos and the distributional maps for all species are provided. Four new combinations are proposed: Epeusdilucidus (Próchniewicz, 1990), comb. nov., and E.guangxi (Peng & Li, 2002), comb. nov. transferred from Plexippoides Prószynski, 1984, Phintellasufflava (Jastrzebski, 2009), comb. nov. transferred from Carrhotus Thorell, 1891, and Yaginumaellaarmata (Jastrzebski, 2011), comb. nov. transferred from Pancorius Simon, 1902.

16.
Zookeys ; 1190: 75-89, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38298405

RESUMO

Guigarracailaoensis is a member of family Cyprinidae, subfamily Labeoninae (Cypriniformes) which was recently discovered in southwestern China. Following its initial description, additional information on this species has remained notably scarce. In the current study, we assemble the complete mitochondrial genome (mitogenome) of G.cailaoensis using the Illumina sequencing platform. The mitogenome is identified as a circular, double-stranded DNA sequence of 16,593 base pairs, encompassing 13 protein-coding genes (PCGs), 22 transfer RNA genes, two ribosomal RNA genes, and a putative control region. Maximum-likelihood and Bayesian-inference approaches were used to construct phylogenetic trees for three datasets: (i) PCG sequences of the complete mitogenome (dataset 1); (ii) PCG sequences of the complete mitogenome combined with nuclear DNA (ncDNA) (Rag1) sequence (dataset 2); and (iii) ncDNA (Rag1) sequences (dataset 3). Phylogenetic analyses position G.cailaoensis as a sister taxon to the lineage consisting of Paraqianlabeolineatus Zhao, Sullivan, Zhang & Peng, 2014 and Pseudogyrinocheilusprochilus Fang, 1933 in dataset 1, and to Pseudogyrinocheilusprochilus in dataset 2, species lacking an oral disc on the lower lip. However, G.cailaoensis showed a close relationship to the lineage consisting of Discogobio and Discocheilus in dataset 3, species possessing an oral disc on the lower lip. Nonetheless, a variety of species with an oral disc on the lower lip are clustered into different lineages across the three datasets that may indicate that the development of the oral disc is homoplastic within the subfamily Labeoninae. The outcomes of this study have the potential to support conservation efforts for this species and to enrich our understanding of genetic resources in the area.

17.
Sci Total Environ ; 931: 172709, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38670367

RESUMO

While significant progress has been achieved in utilizing remote sensing technologies for landslide investigation in China, there remains a notable gap in consolidating information on applicable conditions, application stages, and workflows across various remote sensing methodologies. This paper proposes a comprehensive framework for active landslide detection, incorporating multiple stages and data sources, successfully implemented in a vast region of southwestern China. Furthermore, detailed discussions are provided on the effects of the geometric distortion, land cover type, and various InSAR methods on the accuracy of active landslide identification results. Additionally, the paper delves into the advantages of integrated remote sensing technology in active landslide investigation, encompassing the assessment of current landslide activity status, precise delineation of boundaries, identification of different deformation stages, and determination of damage patterns. Through comprehensive analysis of multisource data, it enhances understanding of the active landslide process, ultimately contributing to the mitigation of casualties and property damage.

18.
Zookeys ; 1176: 1-11, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37654979

RESUMO

Homidiacingula Börner, 1906, the type species of the genus Homidia Börner, 1906, is widespread from India to Southeast Asia, but its detailed morphological characteristics have not yet been described. We examined the morphology of specimens of H.cingula from Indonesia and southwestern China and confirmed their conspecific status by comparing their DNA barcoding sequences. We also compared the morphology of H.cingula with other two closely related species, confirming the valid species status of H.subcingula Denis, 1948. Our study provides new taxonomic and molecular data for the genus Homidia.

19.
Zookeys ; 1168: 219-229, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38328628

RESUMO

Two new species of Phaonia are described: Phaoniaagitata Zhou & Wei, sp. nov. and Phaonianujiangensis Zhou & Wei, sp. nov., which were collected from Guizhou and Yunnan provinces of southwestern China and are assigned to the boleticola-group. A key to the species of this group is provided. The type specimens are deposited in the Wei Lianmeng Model Worker Innovation Studio, Anshun, Guizhou, China (WLMWISAGC).

20.
Sci Total Environ ; 903: 166562, 2023 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-37633390

RESUMO

Under climate warming, extreme drought events (EDEs) in southwestern China have become more frequent and severe and have had significant impacts on vegetation growth. Clarifying the influence of soil and meteorological droughts on the vegetation photosynthetic rate (PHR) and respiration rate (RER) can help policymakers to anticipate the impacts of drought on vegetation and take measures to reduce losses. In this study, the frequency and features of EDEs from 1990 to 2021 were analyzed using the standardized precipitation evapotranspiration index, and the longest-lasting and most severe EDE was chosen to assess the effects of drought on vegetation activity. Then, a land surface model was used to simulate the vegetation PHR and RER. Finally, the effects of the EDE on the vegetation PHR and RER were analyzed from the perspectives of soil and meteorological droughts. The results revealed that from 1990 to 2021, a total of 11 EDEs were observed in southwestern China, and the longest-lasting and most severe EDE occurred in 2009-2010 (EDE2009/2010). EDE2009/2010 significantly reduced the monthly mean PHR and RER by 9.82 g C m-2 month-1 and 0.80 g C m-2 month-1, respectively, causing a cumulative reduction of approximately 5.61 × 1013 g C. Soil and meteorological droughts had a driving force of 39 % on the PHR changes and an explanatory force of 42 % on the RER reduction. In particular, the soil drought had an average explanatory force of 25 % on the PHR and made a contribution of 24 % to the RER. The drought affected different types of vegetation differently, and crops were more susceptible than grassland and forests on the monthly time scale. The vegetation exhibited resilience to drought, returning to normal PHR and RER levels 2 months after the end of EDE2009/2010. This research contributes to understanding and predicting the impact of EDEs on vegetation growth in southwestern China.

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