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1.
Mol Ecol ; 2020 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-32306487

RESUMO

Allopatric divergence is often initiated by geological uplift and restriction to sky-islands, climate oscillations, or river capture. However, it can be difficult to establish which mechanism was the most likely to generate the current phylogeographical structure of a species. Recently, genomic data in conjunction with a model testing framework have been applied to address this issue in animals. To test whether such an approach is also likely to be successful in plants, we used population genomic data of the Rheum palmatum complex from the Eastern Asiatic Region, in conjunction with biogeographical reconstruction and demographic model selection, to identify the potential mechanism(s) which have led to the current level of divergence. Our results indicate that the R. palmatum complex originated in the central Hengduan Mts and possibly in regions further east, and then dispersed westward and eastward resulting in genetically distinct lineages. Populations are likely to have diverged in refugia during climate oscillations followed by subsequent expansion and secondary contact. However, model simulations within the western lineage of the R. palmatum complex cannot reject a restriction to sky-islands as a possible mechanism of diversification due to the genetically ambiguous position of one population. This highlights that genetically mixed populations might introduce ambiguity regarding the best diversification model in some cases. Although it might be possible to resolve this ambiguity using other data, sometimes this could prove to be difficult in complex biogeographical areas.

2.
Mitochondrial DNA A DNA Mapp Seq Anal ; 27(4): 2935-6, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26153751

RESUMO

The complete chloroplast genome of the medicinal plant Rheum palmatum L. (Polygonaceae) has been reconstructed from the whole-genome Illumina sequencing data. The genome is 161 541 bp in length, and exhibits a typical quadripartite structure of the large (LSC, 86 518 bp) and small (SSC, 13 111 bp) single-copy regions, separated by a pair of inverted repeats (IRs, 30 956 bp each). The chloroplast genome contains 131 genes, including 84 protein-coding genes (78 PCG species), eight ribosomal RNA genes (four rRNA species) and 37 transfer RNA genes (28 tRNA species). Phylogenetic tree based on the maximum parsimony (MP) analysis of 65 chloroplast protein-coding genes for 13 taxa demonstrated a close relationship between R. palmatum and Fagopyrum esculentum subsp. ancestrale in Polygonaceae.


Assuntos
Genoma de Cloroplastos , Rheum/classificação , Rheum/genética , Composição de Bases , Genes de Cloroplastos , Genes de Plantas , Tamanho do Genoma , Fases de Leitura Aberta , Filogenia , Plantas Medicinais/classificação , Plantas Medicinais/genética , Análise de Sequência de DNA , Sequenciamento Completo do Genoma
3.
Zhong Yao Cai ; 38(3): 467-72, 2015 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-26495643

RESUMO

OBJECTIVE: To predict the distribution patterns of the original plants of Rhei Radix et Rhizoma current and in future in China under climate change. METHODS: A maximum entropy modeling and variety of climate change scenarios were employed to predict its current and future distribution ranges in China. RESULTS: The resultant models exhibited excellent predictive power. The current suitable habitats for original plants of Rhei Radix et Rhizoma totaled 84. 20 x 10(4) km2 accounting for 8. 77% of the total area of China; 57. 05% of its current suitable habitats(i. e. low impact areas) would be relatively lowly impacted by the climate change. Compared with its current distribution pattern,its distribution ranges during 2020s, 2030s, 2040s, 2050, 2060s, 2070s and 2080s would be shrunk to some extent. However, the moderately suitable area would be expanded to a certain degree. CONCLUSION: Climate change has a negative impact on the total area and the habitat suitability for the original plants of Rhei Radix et Rhizoma.


Assuntos
Mudança Climática , Ecossistema , Rheum/crescimento & desenvolvimento , China , Raízes de Plantas , Plantas Medicinais/crescimento & desenvolvimento , Rizoma
4.
PLoS One ; 9(10): e110760, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25349989

RESUMO

AIMS: Rheum palmatum complex comprises all taxa within section Palmata in the genus Rheum, including R. officinale, R. palmatum, R. tanguticum, R. tanguticum var. liupanshanense and R. laciniatum. The identification of the taxa in section Palmata is based primarily on the degree of leaf blade dissection and the shape of the lobes; however, difficulties in species identification may arise from their significant variation. The aim of this study is to analyze the patterns of variation in leaf blade characteristics within and among populations through population-based sampling covering the entire distribution range of R. palmatum complex. METHODS: Samples were taken from 2340 leaves from 780 individuals and 44 populations representing the four species, and the degree of leaf blade dissection and the shape of the lobe were measured to yield a set of quantitative data. Furthermore, those data were statistically analyzed. IMPORTANT FINDINGS: The statistical analysis showed that the degree of leaf blade dissection is continuous from lobed to parted, and the shape of the lobe is also continuous from broadly triangular to lanceolate both within and between populations. We suggested that taxa in section Palmata should be considered as one species. Based on the research on the R. palmatum complex, we considered that the quantitative characteristics were greatly influenced by the environment. Therefore, it is not reliable to delimitate the species according to the continuously quantitative vegetative characteristics.


Assuntos
Folhas de Planta/anatomia & histologia , Rheum/anatomia & histologia , Meio Ambiente , Geografia , Fenótipo
5.
PLoS One ; 9(7): e101362, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24988081

RESUMO

AIMS: Fargesia decurvata is closely allied with F. dracocephala and differs in 5 major characters (i.e. the culm sheath blade base shape, the width of the culm sheath blade base, the auricle shape, and the lower surface of leaf blade) in Fargesia. It is difficult to distinguish these two species because of existing of transitional statements of characters. The aims of this paper are to (i) investigate whether the variation of the characters is continuous or not; (ii) reveal whether the publishment of F. dracocephala was the result of discontinuous sampling of F. decurvata or not. METHODS: Ten populations of F. decurvata and F. dracocephala were investigated in their entire distribution (including type localities). The statements of 5 major characters were measured from 693 annual and 693 perennial culms of 231 individuals in 10 populations, and analyzed at population, individual and culm levels. UPGMA cluster analysis was carried out based on 29 characters from 10 populations of F. decurvata and F. dracocephala and 2 populations of F. qinlingensis as outgroup. The ITS sequences were also sequenced and analyzed. IMPORTANT FINDINGS: Five major characters exhibited great variation not only at population level, but at individual level within a population, even the culm level within an individual and in different parts of the same culm. Cluster analyses showed that 10 populations of F. decurvata and F. dracocephala were not divided into two species, but they were well separated with outgroup. There was no difference in floral organ between F. decurvata and F. dracocephala. MP and NJ trees based on ITS sequences showed the same results with the cluster analysis on morphological characters. All the facts indicated that the publishment of F. dracocephala was the result of discontinuous sampling of F. decurvata, and F. dracocephala should be treated as the synonym of F. decurvata.


Assuntos
Poaceae/anatomia & histologia , Poaceae/genética , Análise por Conglomerados , DNA de Plantas/genética , DNA Espaçador Ribossômico/genética , Folhas de Planta/anatomia & histologia , Folhas de Planta/classificação , Folhas de Planta/genética , Poaceae/classificação , Análise de Sequência de DNA
6.
Zhonghua Nan Ke Xue ; 19(3): 223-7, 2013 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-23700727

RESUMO

OBJECTIVE: To investigate the impact of infertility on men's self-esteem, self-confidence, sexual satisfaction and overall relationship with their spouses. METHODS: Using Self-Esteem and Relationship questionnaire (SEAR), we conducted an investigation among 253 infertile men and 52 fertile male controls. We divided the infertile men into four subgroups according to their perceived causes of infertility: male (M) factors, female (F) factors, both M and F factors, and unknown factors, and compared the SEAR scores among different groups. RESULTS: In the infertile men, the total SEAR score was significantly higher in those with < 3 years than in those with > or = 3 years of infertility duration (75.50 +/- 17.05 vs 68.66 +/- 17.19, P < 0.05) and so was it in those with above-high-school than in those with high-school or lower education background (81.42 +/- 13.99 vs 67.61 +/- 17. 8, P < 0.01), but showed no significant difference between the > or = 30- and < 30-year-olds (71.77 +/- 17.42 vs 72.74 +/- 18.38, P > 0.05). The total SEAR scores in the M factor, M & F factor, unknown factor and F factor groups were 65.69 +/- 18.68, 68.52 +/- 17.68, 74.85 +/- 15.19 and 83.21 +/- 12.61, respectively, with significant differences between the first two and the latter two groups (P < 0.05), as well as between the unknown factor and F factor groups (P < 0.05). In the fertile male controls, the total SEAR score and subdomain scores on sexual relationship, self-confidence, self-esteem and overall relationship were 90.04 +/- 9.85, 88.40 +/- 10.74, 92.23 +/- 9.41, 91.95 +/- 10.67 and 90.38 +/- 14.14, respectively, all remarkably higher than in the M factor, M&F factor and unknown factor groups of the infertile men after adjustment of their infertility duration and education levels (P < 0.05). CONCLUSION: Infertility reduces men's self-esteem, self-confidence, sexual satisfaction and relationship with their spouses, and the degree of its impact is correlated with the patients' infertility duration and education level.


Assuntos
Infertilidade Masculina/psicologia , Satisfação Pessoal , Autoimagem , Adulto , Disfunção Erétil/psicologia , Humanos , Masculino , Inquéritos e Questionários
7.
Zhonghua Nan Ke Xue ; 19(12): 1087-90, 2013 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-24432619

RESUMO

OBJECTIVE: To evaluate the impact of the factors of perceived male infertility on men's penile erectile function. METHODS: Using the 5-item version of the International Index of Erectile Function (IIEF-5), we investigated the penile erectile function among 245 infertile men (infertility group) and another 52 males having physical checkup for planned conception (checkup group), the former further divided into four subgroups according to the factors of infertility: male factor, female factor, bilateral factor, and unknown factor. We compared the total and item scores of IIEF-5 among different groups. RESULTS: Mild or mild-moderate ED was found in 50.61% of the infertile men, with a total IIEF-5 score of 21.24 +/- 2.58. The total and item scores of IIEF-5 were markedly higher in the male factor than in the female factor subgroup (P < 0.01), but with no significant difference between the male factor subgroup and the bilateral and unknown factor subgroups (P > 0.05), except the score on confidence. The scores were significantly lower in the bilateral and unknown factor subgroups than in the female factor subgroup (P < 0.05), with no remarkable difference between the former two. In the infertility group, the total and item scores of IIEF-5 were markedly higher in those with education above high school than in those with high school or lower education (P < 0.01), but not correlated with age and infertility duration. After adjustment for education background, the total IIEF-5 score and the scores on confidence and satisfaction were significantly lower in the infertility than in the checkup group (P < 0.05), and 15.38% of the men in the latter group had mild ED, dramatically lower than in the former (P < 0.01). CONCLUSION: Perceived infertility may cause ED in males, and a higher incidence rate is associated with lower education background of the men.


Assuntos
Disfunção Erétil/epidemiologia , Infertilidade Masculina/fisiopatologia , Pênis/fisiopatologia , Adulto , Humanos , Masculino , Ereção Peniana , Inquéritos e Questionários , Adulto Jovem
8.
Int J Mol Sci ; 13(3): 3900-15, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22489188

RESUMO

Rheum officinale Baill., an important but endangered medicinal herb, is endemic to China. Inter-simple sequence repeat (ISSR) markers were employed to investigate the genetic diversity and differentiation of 12 populations of R. officinale. Thirteen selected primers yielded 189 bright and discernible bands, with an average of 14.54 per primer. The genetic diversity was low at the population level, but pretty high at the species level (H = 0.1008, I = 0.1505, PPB = 28.95% vs. H = 0.3341, I = 0.5000, PPB = 95.24%, respectively) by POPGENE analysis. Analysis of molecular variance (AMOVA) showed that the genetic variation was found mainly among populations (74.38%), in line with the limited gene flow (N(m) = 0.2766) among populations. Mantel test revealed a significant correlation between genetic and geographic distances (r = 0.5381, P = 0.002), indicating the role of geographic isolation in shaping the present population genetic structure. Both Bayesian analysis and UPGMA cluster analysis demonstrated the similar results. Our results imply that the conservation efforts should aim to preserve all the extant populations of this endangered species, and cultivation is proposed in this study.


Assuntos
Repetições de Microssatélites/genética , Isolamento Reprodutivo , Rheum/genética , Sequência de Bases , Análise por Conglomerados , Primers do DNA/genética , Fluxo Gênico , Variação Genética , Genética Populacional , Geografia , Plantas Medicinais/genética , Rheum/classificação , Análise de Sequência de DNA
9.
Ann Bot ; 109(6): 1125-32, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22401850

RESUMO

BACKGROUND AND AIMS: Preliminary field observations in 2001 and 2002 suggested that Kingdonia uniflora (Circaeasteraceae, Ranunculales) exhibits heterodichogamy, an unusual kind of reproductive heteromorphy, hitherto unreported in Ranunculales and known from only one other genus in basal eudicots. METHODS: During several subsequent years flowers were observed in the field. Flowers were fixed in FAA and studied with microtome sections series and with the scanning electron microscope. KEY RESULTS: The flowers proved to be heterodichogamous, with protandrous and protogynous morphs, which have a 1 : 1 ratio. Both morphs equally set fruit. Each year a single flower is formed at the tip of a rhizome or more rarely two flowers. The flowers are already open when they appear at the soil surface, before they are receptive and before pollen is dispersed. In both floral morphs the styles elongate early and the stigmas are positioned above the anthers before anthesis begins. In protogynous flowers the stigmas become receptive in this position; later the styles become reflexed and then the anthers dehisce. In contrast, in protandrous flowers the stamen filaments elongate during early anthesis such that the dehiscing anthers come to lie above the (still unreceptive) stigmas; after dehiscence of all anthers in a flower the styles begin to elongate and become receptive. CONCLUSIONS: This is the first record of heterodichogamy in a representative of Ranunculales, in an herbaceous eudicot, and in a plant with uniflorous ramets. The occurrence of heterodichogamy in Kingdonia in which clonal reproduction appears to be dominant might be an adaptation to avoid mating between the ramets from a common mother individual (genet).


Assuntos
Flores/fisiologia , Flores/ultraestrutura , Organismos Hermafroditas/classificação , Organismos Hermafroditas/fisiologia , Magnoliopsida/classificação , Magnoliopsida/fisiologia , China , Reprodução
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