The science and economics of ex situ plant conservation

Many of the epiphytic orchids are used as traditional medicine. Chemical components and pharmacology have been studied in recent 15 years. Medicinal orchids, in general, are not subjected to detailed pharmacological studies. A wide range of chemical compounds are presented including alkaloids, bibenzyl derivatives, flavonoids, phenanthrenes and terpenoids which have been isolated recently from this species. Extracts and metabolites of these plants, particularly those from flowers and leaves, possess useful pharmacological activities. Particular attention has been given to diuretic, anti-rheumatic, anti-inflammatory, anti-carcinogenic, hypoglycemic activities, antimicrobial, anticonvulsive, relaxation, neuroprotective, and antivirus, activities. A comprehensive account of chemical constituents and biological activities is presented and a critical appraisal of the ethnopharmacological issues is included in view of the many recent findings of importance of these orchids. A large number of orchids have been empirically used for treatment of different diseases, thus, several studies have been undertaken to provide scientific proof to justify the medicinal use of various plants in treatment of diseases. The aim of this review is to up-date and to present a comprehensive analysis of traditional and folklore uses, pharmacological reports and phyto-constituents isolated from the orchids family.

	 

	Key words: Orchids, medicinal plant, traditional uses, chemical constituents, biological activities.

https://www.academicjournals.org/article/article1380546355_Gutiérrez.pdf

Orchids : A review of uses in traditional medicine, its phytochemistry and pharmacology

Orchids are nature's most extravagant group of flowering plants distributed throughout the world from tropics to high alpine. They exhibit incredible range of diversity in size, shape and color of their flowers. Though orchids are grown primarily as ornamentals, many are used as herbal medicines, food, and other have cultural value by different cultures and tribes in different parts of the world. Orchids have been used in many parts of the world in traditional healing system as well as in the treatment of a number of diseases since the ancient time. Though Orchidaceae is regarded as a largest family of plant kingdom, few studies have been done regarding their medicinal properties. Linking of the indigenous knowledge of medicinal orchids to modern research activities provides a new reliable approach, for the discovery of novel drugs much more effectively than with random collection. Many of these orchids face the extreme danger of extinction due to over-exploitation and habitat loss. Plant tissue culture could be one of the most suitable alternative tools to minimize the pressure on natural population of medicinal orchids and their sustainable utilization.

	 

	Key words: Medicinal, orchids, propagation, conservation, culture.

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Medicinal orchids and their uses: Tissue culture a potential alternative for conservation

Allopolyploidization accounts for a significant fraction of speciation events in many eukaryotic lineages. However, existing phylogenetic and dating methods require tree-like topologies and are unable to handle the network-like phylogenetic relationships of lineages containing allopolyploids. No explicit framework has so far been established for evaluating competing network topologies, and few attempts have been made to date phylogenetic networks. We used a four-step approach to generate a dated polyploid species network for the cosmopolitan angiosperm genus Viola L. (Violaceae Batch.). The genus contains ca 600 species and both recent (neo-) and more ancient (meso-) polyploid lineages distributed over 16 sections. First, we obtained DNA sequences of three low-copy nuclear genes and one chloroplast region, from 42 species representing all 16 sections. Second, we obtained fossil-calibrated chronograms for each nuclear gene marker. Third, we determined the most parsimonious multilabeled genome tree and its corresponding network, resolved at the section (not the species) level. Reconstructing the "correct" network for a set of polyploids depends on recovering all homoeologs, i.e., all subgenomes, in these polyploids. Assuming the presence of Viola subgenome lineages that were not detected by the nuclear gene phylogenies ("ghost subgenome lineages") significantly reduced the number of inferred polyploidization events. We identified the most parsimonious network topology from a set of five competing scenarios differing in the interpretation of homoeolog extinctions and lineage sorting, based on (i) fewest possible ghost subgenome lineages, (ii) fewest possible polyploidization events, and (iii) least possible deviation from expected ploidy as inferred from available chromosome counts of the involved polyploid taxa. Finally, we estimated the homoploid and polyploid speciation times of the most parsimonious network. Homoploid speciation times were estimated by coalescent analysis of gene tree node ages. Polyploid speciation times were estimated by comparing branch lengths and speciation rates of lineages with and without ploidy shifts. Our analyses recognize Viola as an old genus (crown age 31 Ma) whose evolutionary history has been profoundly affected by allopolyploidy. Between 16 and 21 allopolyploidizations are necessary to explain the diversification of the 16 major lineages (sections) of Viola, suggesting that allopolyploidy has accounted for a high percentage—between 67% and 88%—of the speciation events at this level. The theoretical and methodological approaches presented here for (i) constructing networks and (ii) dating speciation events within a network, have general applicability for phylogenetic studies of groups where allopolyploidization has occurred. They make explicit use of a hitherto underexplored source of ploidy information from chromosome counts to help resolve phylogenetic cases where incomplete sequence data hampers network inference. Importantly, the coalescent-based method used herein circumvents the assumption of tree-like evolution required by most techniques for dating speciation events. (Dating; low-copy nuclear gene; polyploidy; species network; Viola; violaceae.)

From Gene Trees to a Dated Allopolyploid Network: Insights from the Angiosperm Genus Viola (Violaceae)

Tribe Orchideae dominates the orchid flora of the temperate Northern Hemisphere but its representatives in East Asia had been subject to less intensive phylogenetic study than those in Eurasia and North America Although this situation was improved recently by the molecular phylogenetic study of Jin et al, comparatively few species were analyzed from the species-rich and taxonomically controversial East Asian Amitostigma alliance Here, we present a framework nrITS tree of 235 accessions of Orchideae plus an in-depth analysis of 110 representative accessions, encompassing most widely recognized species within the alliance, to elucidate their relationships We used parsimony, likelihood and Bayesian approaches to generate trees from data for two nuclear (nrITS, low-copy Xdh) and four chloroplast (matK, psbA-trnH, trnL-F, trnS-trnG) markers Nuclear and plastid data were analyzed separately due to a few hard incongruences that most likely reflect chloroplast capture Our results suggest key phylogenetic placements for Sirindhornia and Brachycorythis, and confirm previous assertions that the Amitostigma alliance is monophyletic and sister to the Eurasian plus European clades of subtribe Orchidinae Seven robust clades are evident within the alliance, but none corresponds precisely with any of the traditional genera; the smaller and more morphologically distinct genera Tsaiorchis, Hemipilia, Neottianthe and Hemipiliopsis are monophyletic but each is nested within a polyphyletic plexus of species attributed to either Ponerorchis or the most plesiomorphic genus, Amitostigma Two early-divergent clades that escaped analysis by Jin et al undermine their attempt to circumscribe an expanded monophyletic genus Ponerorchis We provide a new framework on the complex phylogenetic relationships between Amitostigma and other genera traditionally included in its alliance; based on which, we combine the entire Amitostigma alliance into a morphologically and molecularly circumscribed Amitostigma sensu latissimo that also contains seven molecularly circumscribed sections Our molecular trees imply unusually high levels of morphological homoplasy, but these will need to be quantified via a future group-wide review of the alliance based on living plants if morphology is to be fully integrated into our classification

/pdf/phylogeny-and-classification-of-the-east-asian-amitostigma-298m8uafi0.pdf

Phylogeny and classification of the East Asian Amitostigma alliance (Orchidaceae: Orchideae) based on six DNA markers

The Paracel Islands (Xisha Islands) comprise a group of tropical islands that are located south of mainland China and have a particular natural flora. Based on a literature search and our own investigations, we present here a checklist of plants for 24 of the Paracel Islands. We also report an analysis of plant diversity, its distribution and relationship with that of neighboring regions. A total of 396 vascular plants were recorded which belonged to 262 genera and 85 families. Of these, 220 were wild species and 176 were cultivated. As a whole, the islands do not possess a rich flora; however, there are major differences in plant diversity among islands. The flora consists in large part of tropical elements, typical of tropical coral islands of China. The flora is most closely connected to that of Hainan Island, and closely related to those of Taiwan of China, Indochina, Malaysia, Indonesia and the Philippines.

https://www.biodiversity-science.net/EN/article/downloadArticleFile.do?attachType=PDF&id=8620

Vascular plant diversity of the Paracel Islands, China

Infrageneric phylogeny of the genus Viola (Violaceae) based on trnL-trnF, psbA-trnH, rpl16, ITS sequences, cytological and morphological data.

Endemic plants occurring in limestone of Hainan Province consist of 63 species in 52 genera and 37 families, of which 18 species are restricted to Hainan only. About 84% of the species are of tropical elements. Changjiang County of western Hainan is considered to be the centre of the distribution of endemic plants on the island. However, endemism in the limestone flora of Hainan is not obvious as compared to that of neighboring Provinces. A list of endemic species distributed in limestone region on Hainan is tabulated.

Endemic plants in limestone region on Hainan Island

A new species of Viola L. from Guangdong Province, China, V. guangzhouensis A. Q. Dong, J. S. Zhou & F. W. Xing, is described and illustrated here. The new taxon represents a fifth species in Viola sect. Diffusae (W. Becker) Ching J. Wang, and a taxonomic key to distinguish these taxa in China is included. Viola guangzhouensis is distinct from the sympatric V. diffusa Gingins by having obviously aerial stems, brownish purple stolons, and a bearded anterior petal. The new species is a narrow endemic, collected only from Dalingshan in Guangzhou, Guangdong Province, and is assessed as Critically Endangered (CR).

/pdf/a-new-species-of-viola-violaceae-from-guangdong-china-1h8o66l9h5.pdf

A New Species of Viola (Violaceae) from Guangdong, China

Fifteen medicinal Bulbophyllum species in China are presented. The local names, distribution, habitat, and folk medicinal uses are given. Bulbophyllum species used as folk herbs are mostly distributed in south and south-west China, in particular, in Yunnan Province. Some species such as B. kwangtungense, B. odoratissimum and B. ambrosia are common in Guangdong and Guangxi. Some suggestions for the conservation and reasonableutilization of the plant resources are made.

Xing FuWu

Papers

Vascular plant diversity of the Paracel Islands, China

Infrageneric phylogeny of the genus Viola (Violaceae) based on trnL-trnF, psbA-trnH, rpl16, ITS sequences, cytological and morphological data.

Endemic plants in limestone region on Hainan Island

A New Species of Viola (Violaceae) from Guangdong, China

Medicinal plants of {\sl Bulbophyllum} species in China