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1.
PhytoKeys ; 188: 19-29, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35095290

RESUMO

Carexmalipoensis, a new species from southeast Yunnan, China, is here described and illustrated. It is morphologically similar to C.trichophylla in sect. Euprepes, but differs from it by its longer inflorescences and peduncles, pendulous spikes, hispidulous female glumes, densely hispidulous utricles, and longer nutlets.

2.
PhytoKeys ; 181: 105-111, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34611456

RESUMO

Vacciniummotuoense (Ericaceae), a new species from Motuo County, Xizang Autonomous Region, China is described and illustrated. This new species belongs to Vacciniumsect.Calcicolus and is morphologically most similar to V.dunalianum, but differs in having yellowish-brown tomentose young branches, petioles and inflorescence rachis, leaf blades with 2-3(-4) pairs of secondary veins, usually all basal and with fine veins impressed adaxially and urceolate to spherical corollas.

3.
Front Plant Sci ; 12: 646133, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33936133

RESUMO

Paralamium (Lamiaceae) is a monotypic genus within the subfamily Lamioideae and has a sporadic distribution in subtropical mountains of southeast Asia. Although recent studies have greatly improved our understanding of generic relationships within Lamioideae, the second most species-rich subfamily of Lamiaceae, the systematic position of Paralamium within the subfamily remains unclear. In this study, we investigate the phylogenetic placement of the genus using three datasets: (1) a 69,276 bp plastome alignment of Lamiaceae; (2) a five chloroplast DNA region dataset of tribe Pogostemoneae, and (3) a nuclear ribosomal internal transcribed spacer region dataset of Pogostemoneae. These analyses demonstrate that Paralamium is a member of Pogostemoneae and sister to the monotypic genus Craniotome. In addition, generic-level phylogenetic relationships within Pogostemoneae are also discussed, and a dichotomous key for genera within Pogostemoneae is provided.

4.
PhytoKeys ; 161: 1-9, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33005086

RESUMO

The border area between south-eastern Yunnan, China and northern Vietnam is one of the regions with richest biological diversity including that of the fern genus Angiopteris (Marattiaceae). Based on the analysis of morphology and DNA sequences of multiple chloroplast regions (atpB, rbcL, rps4-trnS spacer and trnL-F spacer), we revised Angiopteris tonkinensis (Hayata) J.M.Camus and proposed a new combination Angiopteris tamdaoensis (Hayata) J.Y.Xiang & T.Wang, comb. nov., which was previously regarded as a synonym of A. tonkinensis. We found support for a monophyletic Angiopteris including Protomarattia. This discovery adds two new distribution sites of A. tonkinensis, one in China (Malipo, Yunnan) and one in Vietnam (Quan Ba, Ha Giang). We suggest A. tonkinensis should be categorised as Critically Endangered (CR) species according to the criteria of IUCN.

5.
PLoS One ; 15(5): e0232602, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32379799

RESUMO

Scutellaria, or skullcaps, are medicinally important herbs in China, India, Japan, and elsewhere. Though Scutellaria is the second largest and one of the more taxonomically challenging genera within Lamiaceae, few molecular systematic studies have been undertaken within the genus; in part due to a paucity of available informative markers. The lack of informative molecular markers for Scutellaria hinders our ability to accurately and robustly reconstruct phylogenetic relationships, which hampers our understanding of the diversity, phylogeny, and evolutionary history of this cosmopolitan genus. Comparative analyses of 15 plastomes, representing 14 species of subfamily Scutellarioideae, indicate that plastomes within Scutellarioideae contain about 151,000 nucleotides, and possess a typical quadripartite structure. In total, 590 simple sequence repeats, 489 longer repeats, and 16 hyper-variable regions were identified from the 15 plastomes. Phylogenetic relationships among the 14 species representing four of the five genera of Scutellarioideae were resolved with high support values, but the current infrageneric classification of Scutellaria was not supported in all analyses. Complete plastome sequences provide better resolution at an interspecific level than using few to several plastid markers in phylogenetic reconstruction. The data presented here will serve as a foundation to facilitate DNA barcoding, species identification, and systematic research within Scutellaria, which is an important medicinal plant resource worldwide.


Assuntos
Genomas de Plastídeos/genética , Plastídeos/genética , Scutellaria/classificação , Evolução Molecular , Filogenia
6.
PhytoKeys ; 130: 135-141, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31534401

RESUMO

Yushania tongpeii D.Z.Li, Y.X.Zhang & E.D.Liu, a new species of the temperate bamboo tribe Arundinarieae (Poaceae: Bambusoideae), is described and illustrated from north-eastern Yunnan, China. Yushania tongpeii is characterised by taller branching from nodes 1-2 m above the ground, usually three branches at the node, sparse purple spots and thin white powder on the internode, densely purple-spotted culm sheaths, glabrous margins of culm sheaths and tomentose leaf ligules. Based on the morphological features, this new species is assigned to section Yushania.

7.
Ann Bot ; 122(4): 649-668, 2018 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-29945172

RESUMO

Background and Aims: Salvia is the largest genus within Lamiaceae, with about 980 species currently recognized. East Asia, with approx. 100 species, is one of the three major biodiversity centres of Salvia. However, relationships within this lineage remain unclear, and the staminal lever mechanism, which may represent a key innovation within the genus, has been understudied. By using six genetic markers and nearly comprehensive taxon sampling, this study attempts to elucidate relationships and examine evolutionary trends of staminal development within the East Asia (EA) Salvia clade. Methods: Ninety-one taxa of EA Salvia were sampled and 34 taxa representing all other major lineages of Salvia were included for analysis. Two nuclear [internal transcribed spacer (ITS) and external transcribed spacer (ETS)] and four chloroplast (psbA-trnH, ycf1-rps15, trnL-trnF and rbcL) DNA markers were used for phylogenetic analysis employing maximum parsimony (MP), maximum likelihood (ML) and BEAST, with the latter also used to estimate divergence times. Key Results: All Salvia species native to East Asia form a clade, and eight major subclades (A-G) were recognized. Subclade A, comprising two limestone endemics (S. sonchifolia and S. petrophila), is sister to the remainder of EA Salvia. Six distinct stamen types were observed within the EA clade. Stamen type A, with two fully fertile posterior thecae, only occurs in S. sonchifolia and may represent the ancestral stamen type within EA Salvia. Divergence time estimates showed that the crown of EA Salvia began to diversify approx. 17.4 million years ago. Conclusions: This study supports the adoption of a broadly defined Salvia and treats EA Salvia as a subgenus, Glutinaria, recognizing eight sections within this subgenus. Stamen type A is ostensibly plesiomorphic within EA Salvia, and the other five types may have been derived from it. Staminal morphology has evolved in parallel within the EA Salvia, and staminal structure alone is inadequate to delimit infrageneric categories.


Assuntos
Biodiversidade , Evolução Biológica , Salvia/genética , Ásia Oriental , Flores/anatomia & histologia , Flores/genética , Filogenia , Salvia/anatomia & histologia
8.
PeerJ ; 5: e3624, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28804694

RESUMO

Scutellaria wuana, a new species discovered from a xeric valley in Muli County of Sichuan Province in southwest China, is described and illustrated. Morphologically, the new species shares similarities with S. mairei, but can be readily distinguished by a suite of morphological characters including a white-pubescent erect stem, conspicuous leaf petioles, and a yellow corolla with a trapeziform lower-middle lip lobe. The habitat and distribution of S. wuana are also distinctive. The position of the new species within Scutellaria is examined in a phylogenetic context using the nuclear ribosomal internal and external transcribed spacers. Additionally, we examine leaf epidermal and pollen grain micromorphology of the new species and putative relatives.

9.
Plant Divers ; 38(4): 201-206, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30159466

RESUMO

A new species, Lysimachia septemfida (Primulaceae), from Yunnan (Southwest China) is described and illustrated. The new species exhibits several unusual characters in Lysimachia including lack of a corolla, 7-merous flowers, leaves in whorls of 3 and distinct multicellular nodiferous hairs, which make it readily distinguishable from all other species in this genus. The diagnostic differences between this new species and its suppositive allies are given. In addition, the systematic placement of this new species is also discussed based on an ITS molecular tree.

10.
Planta Med ; 80(15): 1304-9, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25153097

RESUMO

Seven new phragmalin limonoids, chukvelutilides I-O (1-7), were isolated from the stem barks of Chukrasia tabularis var. velutina. Their structures were elucidated by extensive spectroscopic analysis. Among them, compound 1 showed moderate lethal activity against brine shrimp larvae, with an LC50 value of 84.1 µM.


Assuntos
Limoninas/química , Animais , Proteínas de Artrópodes/efeitos dos fármacos , Proteínas de Ligação ao Ferro/efeitos dos fármacos , Larva/efeitos dos fármacos , Limoninas/isolamento & purificação , Limoninas/farmacologia , Espectroscopia de Ressonância Magnética , Meliaceae/química , Estrutura Molecular , Casca de Planta/química , Plantas Medicinais/química , Proteínas de Ligação a RNA/efeitos dos fármacos
11.
J Agric Food Chem ; 58(23): 12157-61, 2010 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-21073172

RESUMO

Salvia digitaloides, belonging to the economically and medicinally important genus Salvia, is distributed in the northwest of Yunnan Province, People's Republic of China. The roots of this plant were soaked in alcohol by local Tibetans to make a special traditional "red wine", and many local people like to drink this traditional "red wine" to strengthen physical health. To investigate the bioactive diterpenoid constituents of the roots, a detailed phytochemical study was carried out, and 13 diterpenoids including two new norditerpenoids, dihydroneotanshinlactone (1) and 16,17-dinorpisferal A (2), were isolated. Their structures were established on the basis of detailed spectroscopic analysis. In addition, computational methods were applied to validate the stereochemistry of compound 1. For the bioassay to inhibit the growth of five tumor cell lines, neotanshinlactone (3) exhibited selective cytotoxic activity toward the human breast cancer cell line SK-BR-3, while the other four tanshinones (4-7) showed significant toxicity effects against all of the tested five cell lines.


Assuntos
Diterpenos/química , Medicamentos de Ervas Chinesas/química , Raízes de Plantas/química , Salvia/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Diterpenos/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Humanos , Estrutura Molecular
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