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1.
PhytoKeys ; 237: 103-116, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38292074

RESUMO

Hedysarumqilianshanensesp. nov. (Fabaceae, Hedysareae) is described and illustrated from the Qilianshan Mountains in Gansu, China. This new species is similar to H.przewalskii, but can be distinguished by its corolla being light purple to purple, standard 15-19 mm long, wings 14-16 mm long, keels 16-19 mm long, and the ovary and legume being glabrous. The new species can be easily distinguished from H.neglectum Ledeb. by its bract being shorter than the pedicel, and the ovary and legume being glabrous. Phylogenetic tree based on the nuclear ITS and ETS sequences shows that H.qilianshanense is sister to H.przewalskii, while the tree based on the plastid psbA-trnH, trnC-petN, trnL-F, trnS-G and petN-psbM sequences shows H.qilianshanense as sister to a clade consisting of H.hedysaroides, H.inundatum, H.americanum and H.neglectum. The new species is a diploid with the chromosome number 2n = 14. Based on morphological, phylogenetic and karyotypic evidence, the new species may originate from an ancient homoploid hybrid speciation event.

2.
Ecol Evol ; 12(9): e9351, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36188498

RESUMO

Hybrid zones have been widely highlighted for their interest in understanding evolutionary processes. It is generally accepted that hybrid zones can be maintained in a balance between dispersal and selection. However, the selective forces can either be endogenous (i.e., genetic incompatibilities between parental taxa) or exogenous (i.e., parental taxa are adapted to different environments). In this study, we evaluated these alternatives and determined the maintenance of a narrow hybrid zone between parapatric distributed Oxytropis diversifolia and O. leptophylla in Nei Mongol, China. For 507 individuals sampled from two populations in the hybrid zone, 12 O. diversifolia populations and five O. leptophylla populations, we measured leaf-morphological characteristics, quantified genetic structure using 11 nuclear microsatellite loci and five chloroplast DNA intergenic regions, collected micro- and macrohabitat data, and conducted geographical cline analysis. We found that the two species differed in leaf morphology, and putative hybrids showed either intermediacy or a bias to O. diversifolia. Parental taxa formed two genetically distinct clusters, while populations in the hybrid zone consisted of both parental forms and various admixed individuals, exhibiting a bimodal pattern. The hybrid zone was coupled to ecological transitions of both microhabitat (i.e., the slope) and macroclimatic conditions. However, the genetic clines were significantly narrower than the environmental cline. Our results indicate that endogenous selection can be primarily responsible for maintaining the hybrid zone, while local adaptation accounts for the position of the zone. We further suggest the probable outcome of hybridization could be introgression.

4.
Mitochondrial DNA B Resour ; 6(11): 3117-3118, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34651074

RESUMO

Carex agglomerata C. B. Clarke is a sedge with excellent ornamental characters, it is an important ecosystem stabilizer. Here we report the complete chloroplast genome of C. agglomerata to provide a foundation for further phylogenetic studies on the Cyperaceae. The chloroplast (cp) genome is 184,157 bp in size and consists of a large single-copy (LSC) region 106,654 bp in length, a small single-copy (SSC) region of 36,099 bp, two inverted repeats (IR) regions each 20,702 bp. The total GC content of the cp genome is 33.9% with the LSC, SSC, and IR regions 32, 32.5, and 42.9%, respectively. The cp genome contains 128 genes, including 80 protein-coding, 40 tRNA, and eight rRNA genes. The phylogenetic analysis showed C. agglomerata is in a clade with Carex neurocarpa Maxim and Carex siderosticta Hance. This study provides a basis for further phylogenetic studies of Carex.

5.
Front Plant Sci ; 12: 681962, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34489992

RESUMO

Leaf shape exhibits tremendous diversity in angiosperms. It has long been argued that leaf shape can affect major physiological and ecological properties of plants and thus is likely to be adaptive, but the evolutionary evidence is still scarce. Oxytropis diversifolia (Fabaceae) is polymorphic for leaf shape (1 leaflet, 1-3 leaflets, and 3 leaflets) and exhibits clinal variation in steppes of Nei Mongol, China. With two close relatives predominantly fixed for one phenotype as comparison (Oxytropis neimonggolica with 1 leaflet and Oxytropis leptophylla with 5-13 leaflets), we used a comprehensive cline-fitting approach to assess the role of natural selection in shaping the spatial pattern of leaf-shape variation in this system. For 551 individuals sampled from 22 populations, we quantified leaf-morphological differentiation, evaluated patterns of neutral genetic variation using five chloroplast DNA intergenic regions and 11 nuclear microsatellite loci, and performed microhabitat and macroclimatic-association analyses. We found that 1-leaflet proportions in O. diversifolia populations significantly increased from west to east, and three phenotypes also differed in leaflet-blade size. However, compared with the other two species, populations of O. diversifolia showed little neutral genetic differentiation, and no population structure was detected at either marker. We further revealed that the leaf-shape cline could largely be explained by three macroclimatic variables, with leaflet number decreasing and leaflet-blade size increasing with annual precipitation and showing the reverse trends with temperature seasonality and isothermality. Our results suggest that spatially varying abiotic environmental factors contribute to shape the leaf-shape cline in O. diversifolia, while the interspecific pattern may be due to both local adaptation and historical events.

7.
Mitochondrial DNA B Resour ; 5(3): 2047-2048, 2020 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-33457737

RESUMO

Primula filchnerae Knuth is an endangered species endemic to China. Its complete chloroplast genome was reported in this study for the first time. The whole chloroplast genome was 151, 443 base pairs in length with 131 genes, including 66 protein-coding genes, 37 tRNAs, and 4 rRNAs. In addition, the accD was inferred to be a pseudogene. Phylogenetic analysis showed a sister relationship between P. filchnerae and P. sinensis Sabine ex Lindl.

8.
PhytoKeys ; 132: 53-73, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31607786

RESUMO

Calligonum jeminaicum Z. M. Mao, a species regarded as endemic to China, was thought to be nonexistent owing to a lack of scientific records. The similarity of C. jeminaicum to C. mongolicum Turcz. warranted an investigation into the taxonomical relationship between these species. In this study, a naturally occurring population of C. jeminaicum was discovered and the taxonomical relationships of this species with C. mongolicum were resolved. Morphological traits, including fruit and flower characteristics, as well as nuclear (ETS, ITS) and chloroplast (psbA-trnH, ycf6-psbM, rpl32-trnL, rbcL, and trnL-F) DNA sequence data were studied to confirm the taxonomic status of C. jeminaicum. The nrDNA data (ITS1-2 and ETS) from C. jeminaicum reflected variability from the whole C. mongolicum complex, showing distinctive haplotypes in the Calligonum sect. Medusa Sosk. & Alexandr. The cpDNA data supplied similar evidence, showing unique branching in Bayesian and ML tree analyses. The specific status of C. jeminaicum is confirmed based on both morphological and molecular analyses. Here we present a revised description of C. jeminaicum along with its DNA barcode and discuss suggestions for the conservation of this species. Based on current evidence, this species was evaluated as Critically Endangered (CR) according to the IUCN criteria.

9.
PhytoKeys ; (116): 1-141, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30740023

RESUMO

The composition of many Chenopodiaceae genera in different parts of Himalaya and Tibet has been insufficiently known or contradictory. A revision of the family in Himalaya including Bhutan, Nepal, parts of India (Himachal Pradesh, Jammu and Kashmir, Sikkim and Uttarakhand) and Tibet (Xizang, China) is presented for the first time. Altogether, 57 species from 20 genera are reported, including three species new to science (Agriophyllumtibeticum, Salsolaaustrotibetica and Salsolahartmannii). Atriplexcentralasiatica, Corispermumdutreuilii and Salsolamonoptera are identified as new records for India and Chenopodiumpamiricum is recorded in China for the first time. Dysphaniaambrosioides and Sympegmaregelii are recorded for Xizang. The generic and species keys, species distributions (including maps) and taxonomic notes are provided. We indicate for the first time that the presence of short yellow hairs is the remarkable morphological characteristic of the genus Grubovia. Evident heterocarpy and heterospermy is found in Dysphania for the first time (Dysphaniatibetica). Agriophyllumpungens, Atriplexcrassifolia, Atriplexlaciniata, Atriplexsagittata, Axyrisamaranthoides, Axyrishybrida, Bassiaindica, Corispermumkorovinii, Dysphaniaschraderiana (=Chenopodiumfoetidum auct.), Halocharisviolacea and Suaedamicrosperma are excluded from the species list. Neobotrydiumcorniculatum is synonymised with Dysphaniakitiae, Neobotrydiumlongii with Dysphaniahimalaica and Neobotrydiumornithopodum seems to be conspecific with Dysphanianepalensis. Corispermumladakhianum is a new synonym of Corispermumtibeticum. Amaranthusdiandrus is added to the synonyms of Acroglochinpersicarioides, and Bassiafiedleri, previously considered as conspecific with Gruboviadasyphylla, is added to the synonymy of Bassiascoparia. Lectotypes of Anabasisglomerata (≡Halogetonglomeratus), Halogetontibeticus (=Halogetonglomeratus), Amaranthusdiandrus (=Acroglochinpersicarioides), Chenopodiumtibeticum (≡Dysphaniatibetica), Corispermumdutreuilii, Corispermumfalcatum, Corispermumlhasaense, Corispermumpamiricumvar.pilocarpum (=Corispermumgelidum, syn. nov.), Corispermumtibeticum, Kochiaindica(≡Bassiaindica), Kochiaodontoptera (≡Bassiaodontoptera) and Salsolamonoptera are selected. Out of 53 native elements, 42 are restricted in their distribution to Himalaya and Tibet at altitudes 2000-4500 m above sea level. The greatest taxonomic diversity of the Chenopodiaceae is represented in Jammu and Kashmir (India) and Xizang (China) with a continuous decrease in the number of species southwards.

10.
Phytochemistry ; 159: 65-74, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30594026

RESUMO

A phytochemical study on the aerial parts of Hypericum elatoides led to the isolation of a previously undescribed polycyclic polyprenylated acylphloroglucinol derivative, hyperelatone A, seven previously undescribed phenolic metabolites, hyperelatones B-H, along with ten known analogues. The structures of hyperelatones A-H were elucidated by 1D and 2D NMR spectroscopy, HRESIMS experiment, single-crystal X-ray diffraction and comparison of experimental and calculated ECD spectra, as well as chemical derivatization. All compounds were evaluated for their neuroprotective activity against hydrogen peroxide (H2O2)-induced cell injury in rat pheochromocytoma PC-12 cells and inhibitory effects on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in BV-2 microglial cells. Hyperelatones B-D and H, cinchonain Ib, and tenuiside A showed noticeable neuroprotection at concentrations of 1.0-100.0 µM. Hyperelatones D, G, and H, (-)-epicatechin, tenuiside A, and (Z)-3-hexenyl-ß-D-glucopyranoside exhibited significant anti-neuroinflammatory activity with IC50 values ranging from 0.75 ±â€¯0.02 to 5.83 ±â€¯0.23 µM.


Assuntos
Anti-Inflamatórios/farmacologia , Hypericum/química , Fármacos Neuroprotetores/farmacologia , Fenóis/metabolismo , Floroglucinol/análogos & derivados , Floroglucinol/farmacologia , Componentes Aéreos da Planta/química , Compostos Policíclicos/química , Animais , Anti-Inflamatórios/química , Linhagem Celular , Cristalografia por Raios X , Peróxido de Hidrogênio/metabolismo , Concentração Inibidora 50 , Lipopolissacarídeos/farmacologia , Microglia/citologia , Microglia/efeitos dos fármacos , Microglia/metabolismo , Estrutura Molecular , Fármacos Neuroprotetores/química , Óxido Nítrico/biossíntese , Células PC12 , Floroglucinol/química , Floroglucinol/isolamento & purificação , Prenilação , Ratos , Análise Espectral/métodos
11.
Mitochondrial DNA B Resour ; 4(2): 3762-3763, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-33366179

RESUMO

The first complete chloroplast genome of Oxytropis bicolor Bunge is reported and characterized in this study. The whole chloroplast genome was 122,461 base pairs in length with 110 genes, including 76 protein-coding genes, 30 tRNAs, and 4 rRNAs. In addition, the atpF intron was absent. Maximum-likelihood (ML) phylogenetic analysis indicated that O. bicolor and species of Astragalus were closely related, which is congruent with previous studies.

12.
Appl Plant Sci ; 6(7): e01168, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30131910

RESUMO

PREMISE OF THE STUDY: Microsatellite primers were developed for a perennial legume from northern China, Oxytropis diversifolia (Fabaceae), to investigate population genetic structure of this taxon, as well as potential hybridization events with closely related taxa in this genus. METHODS AND RESULTS: One hundred and five primer pairs were designed from Illumina sequence data and screened for suitability. Fifteen of these primer pairs were polymorphic, and these primers amplified tri-, tetra-, and pentanucleotide repeats with 10-56 alleles per locus. Cross-amplification tests in three other Oxytropis species from northern China (O. leptophylla, O. neimonggolica, and O. squammulosa) revealed that all of these loci can be amplified successfully and show polymorphism. CONCLUSIONS: These primer pairs can be used to assess the genetic diversity and population structure in future studies of O. diversifolia, as well as studies of potential hybridization events with closely related taxa in this genus.

13.
RSC Adv ; 8(47): 26646-26655, 2018 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-35541040

RESUMO

Five new biphenyl ether glycosides, hyperelatosides A-E (1-5), one new benzoate glycoside, hyperelatoside F (6), along with nine known phenolic compounds (7-15), were isolated from the aerial parts of Hypericum elatoides. Their structures were elucidated by 1D and 2D NMR spectroscopy and HRESIMS, as well as chemical derivatization. This is the first report of the identification of biphenyl ether glycosides as plant metabolites and their possible biosynthetic pathway is proposed. Except for 3, the new phenolic metabolites exhibited significant neurotrophic activities to enhance nerve growth factor-induced neurite outgrowth in PC12 cells. In addition, the anti-neuroinflammatory and antioxidant activities of compounds 1-15 were preliminarily evaluated in vitro.

14.
PeerJ ; 5: e3607, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28785518

RESUMO

Previous works resolved diverse phylogenetic positions for genera of the Fabaceae tribe Thermopsideae, without a thoroughly biogeography study. Based on sequence data from nuclear ITS and four cpDNA regions (matK, rbcL, trnH-psbA, trnL-trnF) mainly sourced from GenBank, the phylogeny of tribe Thermopsideae was inferred. Our analyses support the genera of Thermopsideae, with the exclusion of Pickeringia, being merged into a monophyletic Sophoreae. Genera of Sophoreae were assigned into the Thermopsoid clade and Sophoroid clade. Monophyly of Anagyris, Baptisia and Piptanthus were supported in the Thermopsoid clade. However, the genera Thermopsis and Sophora were resolved to be polyphyly, which require comprehensive taxonomic revisions. Interestingly, Ammopiptanthus, consisting of A. mongolicus and A. nanus, nested within the Sophoroid clade, with Salweenia as its sister. Ammopiptanthus and Salweenia have a disjunct distribution in the deserts of northwestern China and the Hengduan Mountains, respectively. Divergence age was estimated based on the ITS phylogenetic analysis. Emergence of the common ancestor of Ammopiptanthus and Salweenia, divergence between these two genera and the split of Ammopiptanthus species occurred at approximately 26.96 Ma, 4.74 Ma and 2.04 Ma, respectively, which may be in response to the second, third and fourth main uplifts of the Qinghai-Tibetan Plateau, respectively.

15.
PLoS One ; 12(1): e0170596, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28122062

RESUMO

The legume family (Fabaceae) exhibits a high level of species diversity and evolutionary success worldwide. Previous phylogenetic studies of the genus Hedysarum L. (Fabaceae: Hedysareae) showed that the nuclear and the plastid topologies might be incongruent, and the systematic position of the Hedysarum sect. Stracheya clade was uncertain. In this study, phylogenetic relationships of Hedysarum were investigated based on the nuclear ITS, ETS, PGDH, SQD1, TRPT and the plastid psbA-trnH, trnC-petN, trnL-trnF, trnS-trnG, petN-psbM sequences. Both nuclear and plastid data support two major lineages in Hedysarum: the Hedysarum s.s. clade and the Sartoria clade. In the nuclear tree, Hedysarum is biphyletic with the Hedysarum s.s. clade sister to the Corethrodendron + Eversmannia + Greuteria + Onobrychis clade (the CEGO clade), whereas the Sartoria clade is sister to the genus Taverniera DC. In the plastid tree, Hedysarum is monophyletic and sister to Taverniera. The incongruent position of the Hedysarum s.s. clade between the nuclear and plastid trees may be best explained by a chloroplast capture hypothesis via introgression. The Hedysarum sect. Stracheya clade is resolved as sister to the H. sect. Hedysarum clade in both nuclear and plastid trees, and our analyses support merging Stracheya into Hedysarum. Based on our new evidence from multiple sequences, Hedysarum is not monophyletic, and its generic delimitation needs to be reconsidered.


Assuntos
DNA de Cloroplastos , Evolução Molecular , Fabaceae/genética , Filogenia , Plastídeos , Núcleo Celular/genética , DNA de Plantas
16.
Phys Rev Lett ; 114(22): 223001, 2015 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-26196619

RESUMO

We demonstrate experimentally the existence of magic wavelengths and determine the ratio of oscillator strengths for a single trapped ion. For the first time, two magic wavelengths near 396 nm for the ^{40}Ca^{+} clock transition are measured simultaneously with high precision. By tuning the applied laser to an intermediate wavelength between transitions 4s_{1/2}→4p_{1/2} and 4s_{1/2}→4p_{3/2}, the sensitivity of the clock transition Stark shift to the oscillator strengths is greatly enhanced. Furthermore, with the measured magic wavelengths, we determine the ratio of the oscillator strengths with a deviation of less than 0.5%. Our experimental method may be applied to measure magic wavelengths for other ion clock transitions. Promisingly, the measurement of these magic wavelengths paves the way to building all-optical trapped ion clocks.

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