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Phylogenetic endemism of the orchids of Megamexico reveals complementary areas for conservation

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Plant Diversity 2022年第4期44卷 351-359页

作者： Brandon E.Gutierrez-Rodríguez Marilyn Vasquez-Cruz Victoria Sosa Instituto de Ecología AC Carretera Antigua a Coatepec 351El Haya91073 XalapaVeracruzMexico Unidad de Genomica Avanzada Laboratorio Nacional de Genomica para La BiodiversidadCentro de Investigaciony Estudios Avanzados IrapuatoLibramiento Norte Carretera Leon Km.9.636821 IrapuatoGuanajuatoMexico

Orchid diversity provides a unique opportunity to further our understanding of biotic and abiotic factors linked to patterns of richness,endemism,and phylogenetic endemism in many regions.However,orchid diversity is consistently threatened by illegal trade and habitat transformation.Here,we identified areas critical for orchid conservation in the biogeographic province of Megamexico.For this purpose,we evaluated orchid endemism,phylogenetic diversity,and phylogenetic endemism within Megamexico and characterized orchid life forms.Our results indicate that the majority of the regions with the highest estimates of endemism and phylogenetic endemism are in southern Mexico and northern Central America,mostly located on the Pacific side of Megamexico.Among the most important orchid lineages,several belong to epiphytic lineages such as Pleurothallidinae,Laeliinae and Oncidiinae.We also found that species from diverse and distantly related lineages converge in montane forests where suitable substrates for epiphytes abound.Furthermore,the southernmost areas of phylogenetic diversity and endemism of Megamexico are in unprotected areas.Thus,we conclude that the most critical areas for orchid conservation in Megamexico are located in southern Mexico and northern Central America.We recommend that these areas should be given priority by the Mexican system of natural protected areas as complementary conservation areas.

关键词： Epiphytes Geophytes orchids Phylogenetic endemism Weighted endemism

Comprehensive phylogenetic analyses of Orchidaceae using nuclear genes and evolutionary insights into epiphytism

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Journal of Integrative Plant Biology 2023年第5期65卷 1204-1225页

作者： Guojin Zhang Yi Hu Ming-Zhong Huang Wei-Chang Huang Ding-Kun Liu Diyang Zhang Haihua Hu Jason L.Downing Zhong-Jian Liu Hong Ma Department of Biology 510 Mueller LaboratoryHuck Institutes of the Life SciencesThe Pennsylvania State UniversityUniversity ParkPennsylvania 16802USA Key Laboratory of National Forestry and Grassland Administration for Orchid Conservation and Utilization at College of Landscape Architecture Fujian Agriculture and Forestry UniversityFuzhou 350002China Shanghai Chenshan Botanical Garden SongjiangShanghai 201602China State Key Laboratory of Systematic and Evolutionary Botany Institute of BotanyChinese Academy of SciencesBeijing 100093China Fairchild Tropical Botanic Garden Coral GablesFlorida 33156USA

Orchidaceae(with>28,000 orchid species)are one of the two largest plant families,with economically and ecologically important species,and occupy global and diverse niches with primary distribution in rainforests.Among orchids,70%grow on other plants as epiphytes;epiphytes contribute up to~50%of the plant diversity in rainforests and provide food and shelter for diverse animals and microbes,thereby contributing to the health of these ecosystems.orchids account for over two-thirds of vascular epiphytes and provide an excellent model for studying evolution of epiphytism.Extensive phylogenetic studies of Orchidaceae and subgroups have;been crucial for understanding relationships among many orchid lineages,although some uncertainties remain.For example,in the largest subfamily Epidendroideae with nearly all epiphytic orchids,relationships among some tribes and many subtribes are still controversial,hampering evolutionary analyses of epiphytism.Here we obtained 1,450 low-copy nuclear genes from 610 orchid species,including 431 with newly generated transcriptomes,and used them for the reconstruction of robust Orchidaceae phylogenetic trees with highly supported placements of tribes and subtribes.We also provide generally wellsupported phylogenetic placements of 131 genera and 437 species that were not sampled by previous plastid and nuclear phylogenomic studies.Molecular clock analyses estimated the Orchidaceae origin at~132 million years ago(Ma)and divergences of most subtribes from 52 to 29 Ma.Character reconstruction supports at least 14 parallel origins of epiphytism;one such origin was placed at the most recent common ancestor of~95%of epiphytic orchids and linked to modern rainforests.Ten occurrences of rapid increase in the diversification rate were detected within Epidendroideae near and after the K-Pg boundary,contributing to~80%of the Orchidaceae diversity.This study provides a robust and the largest family-wide Orchidaceae nuclear phylogenetic tree thus far and new insights into the evolution of epiphytism in

关键词： convergence epiphytes evolution orchids parallel rainforest phylogenomics transcriptome

Non-mycorrhizal fungal endophytes in two orchids of Kaiga forest(Western Ghats), India

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Journal of Forestry Research 2012年第3期23卷 453-460页

作者： Naga M.Sudheep Kandikere R.Sridhar Department of Biosciences Mangalore UniversityMangalagangotriMangalore 574199KarnatakaIndia

We used standard isolation protocols to explore the endophytic fungal communities in three tissue types of two dominant orchids （Bulbophyllum neilgherrense and Vanda testacea） of the Kaiga forest of the Western Ghats. We surface sterilized and assessed 90 segments of each orchid for the occurrence and diversity of endophytic fungal taxa. The 118 fungal isolates were obtained from root, bulb and leaves of B. neilgherrense, consisting of 17 anamorphic taxa （range, 10-15 taxa） with 1.3 fungal taxa per segment （range, 1.2-1.4 taxa）. Four taxa （Aspergillus flavus, A. niger, Penicillium sp. and morpho sp. 1） belonged to the core group （11.1%--32.2%）. The relative abundance of A. flavus and morpho sp. 1 was more than 10%. A total of 130 fungal isolates from roots, stems and leaves of V. testacea yielded 20 anamorphic taxa （range, 11-15 taxa） with 1.4 fungal taxa per segment （range, 1.4-1.5 taxa）. Aspergillusflavus, A. niger, A. ochraceus, Gliocladium viride, Penicillium sp. and morpho sp. 1 belonged to the core group. Relative abundance exceeded 10% for A. flavus, A. niger, and morpho sp. 1. The Simpson and Shannon diversity indices were higher in leaf than root or bulb/stem of both orchids. Jaccard＇s similarity coefficient was higher between root and leaf in both orchids （56.3%-60%） than between other pairs. Our study revealed that the endophytic fungal assemblage and diversity orB. neilgherrense and E testacea of Kaiga forest of the Western Ghats were relatively similar between orchids and their tissues.

关键词： orchids Bulbophyllum Vanda endophytic fungi Western Ghats

Importance of Quercus spp.for diversity and biomass of vascular epiphytes in a managed pine-oak forest in Southern Mexico

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Forest Ecosystems 2022年第3期9卷 366-377页

作者： Nayely Martínez-Meléndez Neptalí Ramírez-Marcial José G. García-Franco Manuel Jesús Cach-Pérez Pablo Martínez-Zurimendi Departamento de Conservacion de la Biodiversidad El Colegio de la Frontera Sur(ECOSUR)San Cristobal de Las Casas29290ChiapasMexico Red de Ecología Functional Instituto de EcologíaA.C.Xalapa91073VeracruzMexico Departamento de Agricultura Sociedad y AmbienteEl Colegio de la Frontera Sur(ECOSUR)Villahermosa86280TabascoMexico

Background:Forestry management modifies the diversity,structure,and functioning of intervened forests.Timber extraction reduces tree density and basal area,leading to changes in the communities of vascular epiphytes.The objective of this study was to evaluate the diversity and biomass of vascular epiphytes in Quercus trees remaining in two pine-oak forest stands that have been subjected to two stages of the Silvicultural Development Method(release cutting,and thinning)in comparison with an unharvested old-secondary forest in southern Mexico.For each treatment,richness of epiphytes present on 60 oak trees was recorded and their dry biomass estimated.We calculated the true diversity(Hill numbers)and beta diversity using the Jaccard coefficient of similarity,and generated rank abundance curves per taxonomic epiphyte group(bromeliads,orchids,ferns and others).For each treatment,the relationships between overall diversity and epiphyte biomass to the host trees basal area were analyzed using log linear models.Results:We recorded a total of 67 species of epiphytes species belonging to 10 families hosted by five species of oaks.The greatest species richness(^(0)D)was recorded in the old-secondary forest.Fewer common(^(1)D)and dominant(^(2)D)species were recorded in the release cutting than in the other treatments.Epiphyte diversity and biomass were both slightly related to host tree basal area.Composition of epiphytes was similar(60%)among treatments,although orchids,bromeliads,and other families were more diverse in the old-secondary forest.Most bromeliad species were shared across all treatments,although orchids presented the most exclusive species in the unharvested forest.The bromeliad Tillandsia seleriana provided the greatest contribution to biomass in all treatments,followed by the orchid Camaridium densum.Generalized linear models indicated that epiphyte diversity was significantly related to treatment,and epiphyte biomass to basal area of host trees.Conclusions:Although forest management affects diversity,compos

关键词： Bromeliads Chiapas Ferns orchids Richness Sierra Madre Silvicultural development method(SDM)

Efficiency of microsatellite isolation from orchids via next generation sequencing

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Open Journal of Genetics 2012年第4期2卷 167-172页

作者： Madhav Pandey Jyotsna Sharma Department of Plant and Soil Science Texas Tech University Lubbock USA

Microsatellites, or simple sequence repeats (SSRs), are highly polymorphic, co-dominant genetic markers commonly used for population genetics analyses although de novo development of species specific microsatellites is cost-and time-intensive. Orchidaceae is one of the most species-rich families of angiosperms with more than 30,000 species estimated. Despite its high species-diversity, microsatellites are available only for a few species and all were developed by only using Sanger sequencing methods. For the first time in orchids, we used 454 GS-FLX sequencing to isolate microsatellites in two species (Cypripedium kentuckiense and Pogonia ophioglossoides), and report preliminary results of the study. From 1/16th plate that was subjected to sequencing, 32,665 reads were generated, from which 15,473 fragments contained at least one SSR. We selected 20,697 SSRs representing di-, tri-, and tetra-nucleotides. While 3,674 microsatellites had flanking regions on both sides, useable primer pairs could be designed for 255 SSRs. The mean numbers of reads, SSRs, and SSR-containing reads useful for primer design estimated for other 15 orchid species using Sanger sequencing method were 166, 78 and 31, respectively. Results demonstrate that the efficiency of microsatellite isolation in orchids is substantially higher with 454 GS-FLX sequencing technique in comparison to the Sanger sequencing methods.

关键词： 454 GS-FLX Sequencing Cypripedium kentuckiense Microsatellites orchids Pogonia ophioglossoides Sanger Sequencing

The antioxidant activity of selected wild orchids of Nepal

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Journal of Coastal Life Medicine 2016年第9期4卷 731-736页

作者： Mukesh Babu Chand Mukti Ram Paudel Bijaya Pant Plant Biochemistry and Plant Biotechnology Laboratory Central Department of BotanyTribhuvan UniversityKirtipurKathmanduNepal

Objective:To assess the antioxidant activity as well as the total polyphenolics and flavonoids content of thirteen extracts from nine wild orchids of Nepal.Methods:First,a preliminary phytochemical screening of thirteen extracts of nine orchids was carried out using established protocols.Then,the total polyphenolic and flavonoid contents of each extract were evaluated using the Folin-Ciocalteu's phenol reagent and aluminium chloride methods respectively.Finally,antioxidant activity was determined by 2,2-diphenyl-1-picryl hydrazyl free radical scavenging assay and expressed in terms of half inhibition concentrations(IC50 values).Results:All the tested parameters showed significant variation at P=0.05.The total flavonoids varied with the greatest amounts found in the leaves of Rhynchostylis retusa and the smallest amounts found in the roots of Gastrochilus acutifolius(G.acutifolius).The amount of total polyphenolics was highest in the stems of Vanda cristata and lowest in the leaves of G.acutifolius.Antioxidant activity was highest in the stems of Vanda cristata and lowest in the leaves of G.acutifolius.Conclusions:Some of the orchid extracts studied exhibited levels of antioxidant activity which were comparable to or even higher than those found for extracts of medicinal plants and orchids studied previously.It is suggested that drugs and natural food additives can be extracted from those wild orchids with high levels of antioxidant activity.

关键词： Antioxidant activity Polyphenols Flavonoids orchids

Mycorrhizal fungal community composition in seven orchid species inhabiting Song Mountain, Beijing, China

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Science China(Life Sciences) 2019年第6期62卷 838-847页

作者： Yanhong Chen Yue Gao Linli Song Zeyu Zhao Shunxing Guo Xiaoke Xing Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine Ministry of Education Institute of Medicinal Plant Development Chinese Academy of Medical Sciences and Peking Union Medical College

Mycorrhizal fungi play an important role in the germination and growth of orchids essentially influencing their survival,abundance, and spatial distribution. In this study, we investigated the composition of the mycorrhizal fungal community in seven terrestrial orchid species inhabiting Song Mountain, Beijing, China, using Illumina MiSeq high-throughput sequencing. The mycorrhizal communities in the seven orchids were mainly composed of members of the Ceratobasidiaceae, Sebacinales, and Tulasnellaceae, while a number of ectomycorrhizal fungi belonging to the Russulaceae, Tricholomataceae, Thelephoraceae, and Cortinariaceae were occasionally observed. However, the dominant fungal associates and mycorrhizal community differed significantly among the orchid species as well as subhabitats. These findings confirm the previous observation that sympatric orchid species show different preferences for mycorrhizal fungi, which may drive niche partitioning and contribute to their cooccurrence.

关键词： orchid mycorrhiza fungal community terrestrial orchids fungal diversity

Global climate change is confounding species conservation strategies

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Integrative Zoology 2012年第2期7卷 158-164页

作者： Harold KOOPOWITZ Bradford A.HAWKINS Department of Ecology and Evolutionary Biology University of CaliforniaIrvineCaliforniaUSA

Most organisms face similar problems with respect to their conservation in the face of global climate change.Here,we examine probable effects of climate change on the hyperdiverse plant family Orchidaceae.In the 20th century,the major concerns for orchid conservation revolved around unsustainable harvest for the orchid trade and,more importantly,land conversion from natural ecosystems to those unable to support wild orchid populations.Land conversion included logging,fire regimes and forest conversions to agricultural systems.Although those forms of degradation continue,an additional suite of threats has emerged,fueled by global climate change.Global climate change involves more than responses of orchid populations to increases in ambient temperature.Increasing temperature induces secondary effects that can be more significant than simple changes in temperature.Among these new threats are extended and prolonged fire seasons,rising sea levels,increases in cyclonic storms,seasonal climate shifts,changes in orthographic wind dew point and increased drought.The long-term outlook for orchid biodiversity in the wild is dismal,as it is for many animal groups,and we need to start rethinking strategies for conservation in a rapidly changing world.

关键词： biodiversity climate change conservation biology ex situ conservation orchids

Plant species with extremely small populations(PSESP) in China:A seed and spore biology perspective

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Plant Diversity 2016年第5期38卷 209-220页

作者： Ellie Merrett Wade Jayanthi Nadarajan Xiangyun Yang Daniel Ballesteros Weibang Sun Hugh W.Pritchard Royal Botanic Gardens KewWellcome Trust Millennium Building The Germplasm Bank of Wild Species Kunming Institute of BotanyChinese Academy of Sciences Kunming Botanical Garden Kunming Institute of BotanyChinese Academy of Sciences

Approximately one fifth of the world's plants are at risk of extinction.Of these,a significant number exist as populations of few individuals,with limited distribution ranges and under enormous pressure due to habitat destruction.In China,these most-at-risk species are described as 'plant species with extremely small populations'(PSESP).Implementing conservation action for such listed species is urgent.Storing seeds is one of the main means of ex situ conservation for flowering plants.Spore storage could provide a simple and economical method for fern ex situ conservation.Seed and spore germination in nature is a critical step in species regeneration and thus in situ conservation.But what is known about the seed and spore biology(storage and germination) of at-risk species? We have used China's PSESP(the first group listing) as a case study to understand the gaps in knowledge on propagule biology of threatened plant species.We found that whilst germination information is available for 28 species(23%of PSESP),storage characteristics are only known for 8%of PSESP(10 species).Moreover,we estimate that 60%of the listed species may require cryopreservation for long-term storage.We conclude that comparative biology studies are urgently needed on the world's most threatened taxa so that conservation action can progress beyond species listing.

关键词： Threatened species orchids Storage characteristics Cryopreservation ex situ conservation