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Simpson L, Clements MA, Orel HK, Crayn DM, Nargar K. Plastid phylogenomics clarifies broad-level relationships in Bulbophyllum (Orchidaceae) and provides insights into range evolution of Australasian section Adelopetalum. FRONTIERS IN PLANT SCIENCE 2024; 14:1219354. [PMID: 38854888 PMCID: PMC11157511 DOI: 10.3389/fpls.2023.1219354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Accepted: 11/13/2023] [Indexed: 06/11/2024]
Abstract
The hyperdiverse orchid genus Bulbophyllum is the second largest genus of flowering plants and exhibits a pantropical distribution with a center of diversity in tropical Asia. The only Bulbophyllum section with a center of diversity in Australasia is sect. Adelopetalum. However, the phylogenetic placement, interspecific relationships, and spatio-temporal evolution of this section remain largely unclear. To infer broad-level relationships within Bulbophyllum, and interspecific relationships within sect. Adelopetalum, a genome skimming dataset was generated for 89 samples, which yielded 70 plastid coding regions and a nuclear ribosomal DNA cistron. For 18 additional samples, Sanger data from two plastid loci (matK and ycf1) and nuclear ITS were added using a supermatrix approach. The study provided new insights into broad-level relationships in Bulbophyllum, including phylogenetic evidence for the non-monophyly of sections Beccariana, Brachyantha, Brachypus, Cirrhopetaloides, Cirrhopetalum, Desmosanthes, Minutissima, Oxysepala, Polymeres, and Sestochilos. Section Adelopetalum and sect. Minutissima s.s. formed a highly supported clade that was resolved as a sister group to the remainder of the genus. Divergence time estimations based on a relaxed molecular clock model placed the origin of Bulbophyllum in the Early Oligocene (ca. 33.2 Ma) and sect. Adelopetalum in the Late Oligocene (ca. 23.6 Ma). Ancestral range estimations based on a BAYAREALIKE model identified the Australian continent as the ancestral area of the sect. Adelopetalum. The section underwent crown diversification from the mid-Miocene to the late Pleistocene, predominantly in continental Australia. At least two independent long-distance dispersal events were inferred eastward from the Australian continent to New Zealand and to New Caledonia from the early Pliocene onwards, likely mediated by predominantly westerly winds of the Southern hemisphere. Retraction and fragmentation of the eastern Australian rainforests from the early Miocene onwards are likely drivers of lineage divergence within sect. Adelopetalum facilitating allopatric speciation.
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Affiliation(s)
- Lalita Simpson
- Australian Tropical Herbarium, James Cook University, Cairns, QLD, Australia
- College of Science and Engineering, James Cook University, Cairns, QLD, Australia
| | - Mark A. Clements
- Centre for Australian National Biodiversity Research (joint venture between Parks Australia and Commonwealth Industrial and Scientific Research Organisation (CSIRO)), Canberra, ACT, Australia
| | - Harvey K. Orel
- School of BioSciences, The University of Melbourne, Parkville, VIC, Australia
- National Research Collections Australia, Commonwealth Industrial and Scientific Research Organisation (CSIRO), Canberra, ACT, Australia
| | - Darren M. Crayn
- Australian Tropical Herbarium, James Cook University, Cairns, QLD, Australia
| | - Katharina Nargar
- Australian Tropical Herbarium, James Cook University, Cairns, QLD, Australia
- National Research Collections Australia, Commonwealth Industrial and Scientific Research Organisation (CSIRO), Canberra, ACT, Australia
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Lin L, Cai L, Huang H, Ming S, Sun W. Transcriptome data reveals the conservation genetics of Cypripedium forrestii, a plant species with extremely small populations endemic to Yunnan, China. FRONTIERS IN PLANT SCIENCE 2024; 15:1303625. [PMID: 38357270 PMCID: PMC10864665 DOI: 10.3389/fpls.2024.1303625] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Accepted: 01/08/2024] [Indexed: 02/16/2024]
Abstract
The Cypripedium forrestii is an orchid species with extremely small populations (PSESP) in Yunnan, China. C. forrestii is range-restricted and less-studied than many orchid species, and it is exposed to various threats to its survival. We investigated its potential habitats and collected 52 samples from eight locations, as well as two outgroup species for reference. We developed genetic markers (SNPs) for C. forrestii based on transcriptome sequencing (RNA-seq) data, and analyzed the genetic diversity, population structure, gene flow and demographic history of C. forrestii in detail. C. forrestii is a taxonomically independent species to protect. We found that the genetic diversity of C. forrestii was very low (1.7e-4) compared with other endangered species. We identified three genetic clusters, and several populations with distinct genetic backgrounds. Most genetic diversity was found within sampling sites (87.87%) and genetic clusters (91.39%). Gene flow has been greatly limited over the most recent generations, probably due to geographical distance, historical climate change and habitat fragmentation. We also detected a severe bottleneck event brought about by the recent population constraints. These factors, together with its reproductive characteristics, contribute to the population fragmentation and low genetic diversity of C. forrestii. Based on our findings, we suggest an integrative conservation strategy to protect and recover the genetic diversity of C. forrestii and a further comprehensive study of its ecological traits in the future.
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Affiliation(s)
- Liewen Lin
- Yunnan Key Laboratory for Integrative Conservation of Plant Species with Extremely Small Populations, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan, China
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan, China
- School of Life Science, University of Chinese Academy of Sciences, Beijing, China
| | - Lei Cai
- Yunnan Key Laboratory for Integrative Conservation of Plant Species with Extremely Small Populations, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan, China
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan, China
| | - Hua Huang
- Lijiang Alpine Botanic Garden/ Kunming Botanical Garden, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan, China
| | - Shengping Ming
- Lijiang Alpine Botanic Garden/ Kunming Botanical Garden, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan, China
| | - Weibang Sun
- Yunnan Key Laboratory for Integrative Conservation of Plant Species with Extremely Small Populations, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan, China
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan, China
- Lijiang Alpine Botanic Garden/ Kunming Botanical Garden, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan, China
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Dove A, Charters MD, Campbell MJ, Blake H, Menon M, Sarasan V. Fungal Community Composition at the Last Remaining Wild Site of Yellow Early Marsh Orchid ( Dactylorhiza incarnata ssp. ochroleuca). Microorganisms 2023; 11:2124. [PMID: 37630684 PMCID: PMC10459220 DOI: 10.3390/microorganisms11082124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Revised: 08/01/2023] [Accepted: 08/16/2023] [Indexed: 08/27/2023] Open
Abstract
The yellow early marsh orchid (Dactylorhiza incarnata ssp. ochroleuca) is a critically endangered terrestrial orchid in Britain. Previous attempts to translocate symbiotic seedlings to a site near the last remaining wild site demonstrated some success, with a 10% survival rate despite adverse weather conditions over a two-year period. However, to facilitate future reintroduction efforts or conservation translocations, a more comprehensive understanding of the fungal microbiome and abiotic soil characteristics at the final remaining wild site is required. Obtaining comprehensive information on both the fungal community and soil nutrient composition from wild sites has significant benefits and may prove critical for the success of future conservation translocations involving threatened orchids. This preliminary study, conducted at the last remaining wild site, revealed a significant correlation between the relative abundance of the orchid mycorrhizal fungal order Cantharellales and the concentrations of nitrate and phosphate in the soil. Another orchid mycorrhizal fungal group, Sebacinales, was found to be distributed extensively throughout the site. The composition of fungal communities across the entire site, orchid-hosting and non-orchid-hosting soils is discussed in relation to reinforcing the current population and preventing the extinction of this orchid.
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Affiliation(s)
- Andrea Dove
- Royal Botanic Gardens, Kew, Richmond TW9 3DS, UK
| | | | | | - Hanna Blake
- Department of Geography, University of Sheffield, Sheffield S10 2TN, UK; (H.B.)
| | - Manoj Menon
- Department of Geography, University of Sheffield, Sheffield S10 2TN, UK; (H.B.)
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Yao N, Wang T, Cao X. Epidendrumradicans Fungal Community during Ex Situ Germination and Isolation of Germination-Enhancing Fungi. Microorganisms 2022; 10:microorganisms10091841. [PMID: 36144443 PMCID: PMC9503211 DOI: 10.3390/microorganisms10091841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 08/09/2022] [Accepted: 08/30/2022] [Indexed: 11/19/2022] Open
Abstract
Orchids exhibit varying specificities to fungi in different microbial environments. This pilot study investigated the preference of fungal recruitment during symbiotic germination of Epidendrum radicans Pav. ex Lindl. Two different orchid substrates were used for ex situ seed baiting: pine bark and rotten oak leaf, with Basidiomycota and Ascomycota as the respective dominant groups. Both substrates promoted seed germination, with a higher protocorm formation rate on pine bark (65.75%). High-throughput sequencing characterized the fungal communities of germinated protocorms. Basidiomycota was the dominant group in protocorms that symbiotically germinated on both substrates. The family-level community structures of endophytic fungi in protocorms that symbiotically germinated on both substrates were close to those of protocorms that germinated in vitro on MS1 medium. For protocorms, the dominant fungal groups recruited from substrates differed at the genus level; from pine bark, they were genera belonging to unclassified Sebacinales (41.34%), Thanatephorus (14.48%) and Fusarium (7.35%), while, from rotten oak leaf, they were Rhizoctonia (49.46%), Clitopilus (34.61%), and Oliveonia (7.96%). Four fungal isolates were successfully obtained and identified as belonging to the family Tulasnellaceae, genera Ceratobasidium and Peniophora, which could promote seed germination to the seedling stage. The data indicate that endophytic fungi for E. radicans germination on two different substrates are affected at the genus level by the substrate, with a degree of specificity at the family level.
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Affiliation(s)
- Na Yao
- State Key Laboratory of Tree Genetics and Breeding, Key Laboratory of Tree Breeding and Cultivation of the National Forestry and Grassland Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, China
| | - Tao Wang
- Beijing Laboratory of Urban and Rural Ecological Environment, Beijing Floriculture Engineering Technology Research Centre, China National Botanical Garden, Beijing 100093, China
| | - Xiaolu Cao
- State Key Laboratory of Tree Genetics and Breeding, Key Laboratory of Tree Breeding and Cultivation of the National Forestry and Grassland Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, China
- Correspondence:
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Moreno-Camarena M, Ortega-Larrocea MP. Mesoamerican Cypripedium: Mycorrhizal Contributions to Promote Their Conservation as Critically Endangered Species. PLANTS (BASEL, SWITZERLAND) 2022; 11:1554. [PMID: 35736705 PMCID: PMC9227847 DOI: 10.3390/plants11121554] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Revised: 05/28/2022] [Accepted: 06/09/2022] [Indexed: 06/15/2023]
Abstract
In the valuable orchid genus Cypripedium, the section Irapeana consists of a distinctive group of Mesoamerican species that is formed by Cypripedium dickinsonianum Hágsater, C. irapeanum Lex., and C. molle Lindl. All lady slipper orchids exhibit different distributions and abundances. Data analysis that used herbarium accessions and field investigations indicated that the habitats of these three species have been dramatically reduced. Prospecting for suitable habitats based on climatic, vegetation, and soil parameters allows us to predict potential distributions. Conservation strategies, such as ex situ propagation by asymbiotic and symbiotic approaches, have indicated that the culture media used are a determining factor for seedling development. Mycorrhizal isolates play a main role in the compatibility and further development of germinated seeds. The fungi isolated from adult plants belong to two different families, which makes it possible that widely distributed C. irapeanum populations will be fungal-specific as well as restricted for C. molle. Root mycorrhization patterns occur high on the secondary roots. In contrast with other species of the genus, in situ germination can occur over a short period of two months, but we have documented periods as long as ten years. Cypripedium is a highly problematic genus for ex situ conservation because the germination requirements and cultures are poorly documented, and there is great urgency for in situ conservation to develop strategies for identifying hotspot habitats and actualize the protection status to avoid extinction of this genus.
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Affiliation(s)
- Mauricio Moreno-Camarena
- Posgrado en Ciencias Biológicas, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico;
| | - María Pilar Ortega-Larrocea
- Departamento de Ciencias Ambientales y del Suelo, Instituto de Geología, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico
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Arifin AR, Phillips RD, Weinstein AM, Linde CC. Cryptostylis species (Orchidaceae) from a broad geographic and habitat range associate with a phylogenetically narrow lineage of Tulasnellaceae fungi. Fungal Biol 2022; 126:534-546. [DOI: 10.1016/j.funbio.2022.06.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 06/14/2022] [Accepted: 06/20/2022] [Indexed: 11/04/2022]
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Těšitelová T, Klimešová L, Vogt-Schilb H, Kotilínek M, Jersáková J. Addition of fungal inoculum increases germination of orchid seeds in restored grasslands. Basic Appl Ecol 2022. [DOI: 10.1016/j.baae.2022.04.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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Li YY, Boeraeve M, Cho YH, Jacquemyn H, Lee YI. Mycorrhizal Switching and the Role of Fungal Abundance in Seed Germination in a Fully Mycoheterotrophic Orchid, Gastrodia confusoides. FRONTIERS IN PLANT SCIENCE 2022; 12:775290. [PMID: 35095954 PMCID: PMC8792533 DOI: 10.3389/fpls.2021.775290] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Accepted: 12/17/2021] [Indexed: 06/14/2023]
Abstract
Mycorrhizal associations are essential for orchid germination and seedling establishment, and thus may constrain the distribution and abundance of orchids under natural conditions. Previous studies have shown that germination and seedling establishment in several orchids often decline with increasing distance from adult plants, resulting in non-random spatial patterns of seedling establishment. In contrast, individuals of the fully mycoheterotrophic orchid Gastrodia confusoides often tend to have random aboveground spatial patterns of distribution within bamboo forests. Since G. confusoides is parasitic on litter-decaying fungi, its random spatial patterns of distribution may be due to highly scattered patterns of litter-decaying fungi within bamboo forests. To test this hypothesis, we first identified the main mycorrhizal fungi associating with developing seeds and adult plants at a bamboo forest site in Taiwan using Miseq high-throughput DNA sequencing. Next, we combined seed germination experiments with quantitative PCR (qPCR) analyses to investigate to what extent the abundance of mycorrhizal fungi affected spatial patterns of seed germination. Our results show that seed germination and subsequent growth to an adult stage in G. confusoides required a distinct switch in mycorrhizal partners, in which protocorms associated with a single Mycena OTU, while adults mainly associated with an OTU from the genus Gymnopus. A strong, positive relationship was observed between germination and Mycena abundance in the litter, but not between germination and Gymnopus abundance. Fungal abundance was not significantly related to the distance from the adult plants, and consequently germination was also not significantly related to the distance from adult plants. Our results provide the first evidence that the abundance of litter-decaying fungi varies randomly within the bamboo forest and independently from G. confusoides adults.
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Affiliation(s)
- Yuan-Yuan Li
- Beijing Key Laboratory of Seed Disease Testing and Control, College of Plant Protection, China Agricultural University, Beijing, China
| | - Margaux Boeraeve
- Department of Biology, Plant Conservation and Population Biology, KU Leuven, Leuven, Belgium
| | - Yu-Hsiu Cho
- Biology Department, National Museum of Natural Science, Taichung, Taiwan
| | - Hans Jacquemyn
- Department of Biology, Plant Conservation and Population Biology, KU Leuven, Leuven, Belgium
| | - Yung-I Lee
- Department of Life Science, National Taiwan University, Taipei, Taiwan
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Zhao Z, Shao S, Liu N, Liu Q, Jacquemyn H, Xing X. Extracellular Enzyme Activities and Carbon/Nitrogen Utilization in Mycorrhizal Fungi Isolated From Epiphytic and Terrestrial Orchids. Front Microbiol 2022; 12:787820. [PMID: 34992588 PMCID: PMC8724439 DOI: 10.3389/fmicb.2021.787820] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Accepted: 11/26/2021] [Indexed: 11/22/2022] Open
Abstract
Fungi employ extracellular enzymes to initiate the degradation of organic macromolecules into smaller units and to acquire the nutrients for their growth. As such, these enzymes represent important functional components in terrestrial ecosystems. While it is well-known that the regulation and efficiency of extracellular enzymes to degrade organic macromolecules and nutrient-acquisition patterns strongly differ between major fungal groups, less is known about variation in enzymatic activity and carbon/nitrogen preference in mycorrhizal fungi. In this research, we investigated variation in extracellular enzyme activities and carbon/nitrogen preferences in orchid mycorrhizal fungi (OMF). Previous research has shown that the mycorrhizal fungi associating with terrestrial orchids often differ from those associating with epiphytic orchids, but whether extracellular enzyme activities and carbon/nitrogen preference differ between growth forms remains largely unknown. To fill this gap, we compared the activities of five extracellular enzymes [cellulase, xylanase, lignin peroxidase, laccase, and superoxide dismutase (SOD)] between fungi isolated from epiphytic and terrestrial orchids. In total, 24 fungal strains belonging to Tulasnellaceae were investigated. Cellulase and xylanase activities were significantly higher in fungi isolated from terrestrial orchids (0.050 ± 0.006 U/ml and 0.531 ± 0.071 U/ml, respectively) than those from epiphytic orchids (0.043 ± 0.003 U/ml and 0.295 ± 0.067 U/ml, respectively), while SOD activity was significantly higher in OMF from epiphytic orchids (5.663 ± 0.164 U/ml) than those from terrestrial orchids (3.780 ± 0.180 U/ml). Carboxymethyl cellulose was more efficiently used by fungi from terrestrial orchids, while starch and arginine were more suitable for fungi from epiphytic orchids. Overall, the results of this study show that extracellular enzyme activities and to a lesser extent carbon/nitrogen preferences differ between fungi isolated from terrestrial and epiphytic orchids and may indicate functional differentiation and ecological adaptation of OMF to local growth conditions.
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Affiliation(s)
- Zeyu Zhao
- 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, Beijing, China
| | - Shicheng Shao
- Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Xishuangbanna, China
| | - Na Liu
- 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, Beijing, China
| | - Qiang Liu
- Department of Ecological and Environmental Engineering, Yunnan Forestry Technological College, Kunming, China
| | - Hans Jacquemyn
- Department of Biology, Plant Conservation and Population Biology, KU Leuven, Leuven, Belgium
| | - 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, Beijing, China
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Mycorrhizal Compatibility and Germination-Promoting Activity of Tulasnella Species in Two Species of Orchid (Cymbidium mannii and Epidendrum radicans). HORTICULTURAE 2021. [DOI: 10.3390/horticulturae7110472] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
In nature, Orchidaceae seeds establish a relationship with orchid mycorrhizal fungi to obtain essential nutrients for germination. The orchids, Cymbidium mannii and Epidendrum radicans, have significant ornamental and economic value. We isolated and cultured mycorrhizal fungi from C. mannii, E. radicans, and C. goeringii roots. Three strains of fungi, Tulasnella calospora (Tca), T. asymmetrica (Tas), and T. bifrons (Tbi), were identified using ITS-rDNA sequencing. Their mycorrhizal compatibility, germination-promoting effects, and symbiosis with the seeds of C. mannii and E. radicans were studied in vitro using various concentrations of oatmeal agar (OA) medium. Tca exhibited significant seed-germination-promoting effects on C. mannii (92.1%) and E. radicans (84.7%) on 2.0 and 4.0 g/L OA, respectively. For Tbi and Tas, the highest germination percentages were observed on 4.0 g/L OA in E. radicans (73.60% and 76.49%, respectively). Seed germination in C. mannii was enhanced by high oatmeal concentrations (8.0 and 12.0 g/L) during symbiosis with Tas, whereas Tbi had no effect regardless of OA concentration. Tca exhibited high compatibility with C. mannii and E. radicans, and the oatmeal concentration of the medium affected this compatibility. The findings of this study will aid in the propagation of endangered orchid species for conservation and commercial purposes using mycorrhizal technology.
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Delavaux CS, Weigelt P, Dawson W, Essl F, van Kleunen M, König C, Pergl J, Pyšek P, Stein A, Winter M, Taylor A, Schultz PA, Whittaker RJ, Kreft H, Bever JD. Mycorrhizal types influence island biogeography of plants. Commun Biol 2021; 4:1128. [PMID: 34561537 PMCID: PMC8463580 DOI: 10.1038/s42003-021-02649-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Accepted: 09/07/2021] [Indexed: 11/09/2022] Open
Abstract
Plant colonization of islands may be limited by the availability of symbionts, particularly arbuscular mycorrhizal (AM) fungi, which have limited dispersal ability compared to ectomycorrhizal and ericoid (EEM) as well as orchid mycorrhizal (ORC) fungi. We tested for such differential island colonization within contemporary angiosperm floras worldwide. We found evidence that AM plants experience a stronger mycorrhizal filter than other mycorrhizal or non-mycorrhizal (NM) plant species, with decreased proportions of native AM plant species on islands relative to mainlands. This effect intensified with island isolation, particularly for non-endemic plant species. The proportion of endemic AM plant species increased with island isolation, consistent with diversification filling niches left open by the mycorrhizal filter. We further found evidence of humans overcoming the initial mycorrhizal filter. Naturalized floras showed higher proportions of AM plant species than native floras, a pattern that increased with increasing isolation and land-use intensity. This work provides evidence that mycorrhizal fungal symbionts shape plant colonization of islands and subsequent diversification.
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Affiliation(s)
| | | | | | | | | | | | - Jan Pergl
- Czech Academy of Sciences, Průhonice, Czech Republic
| | - Petr Pyšek
- Czech Academy of Sciences, Průhonice, Czech Republic
| | - Anke Stein
- University of Konstanz, Konstanz, Germany
| | - Marten Winter
- German Centre for Integrative Biodiversity Research, Leipzig, Germany
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Whigham D, McCormick M, Brooks H, Josey B, Floyd R, Applegate J. Isotria medeoloides, a North American Threatened Orchid: Fungal Abundance May Be as Important as Light in Species Management. PLANTS 2021; 10:plants10091924. [PMID: 34579457 PMCID: PMC8471007 DOI: 10.3390/plants10091924] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Revised: 08/30/2021] [Accepted: 09/10/2021] [Indexed: 11/16/2022]
Abstract
The management of endangered or threatened plant species is difficult if protocols are not developed to propagate species for the purpose of restoration or the enhancement of existing populations. The management of endangered and threatened orchids is especially difficult because of the obligate interactions between orchids and orchid mycorrhizal fungi. Isotria medeoloides is a federally threatened forest-dwelling orchid species with a wide distribution in eastern North America. Seeds have not been successfully germinated and current management is based primarily on using subcanopy thinning to increase light in areas where monitoring demonstrates that populations are declining. We report the results of long-term monitoring efforts, canopy thinning, and orchid mycorrhizal fungus abundance studies at two locations in Virginia. The declining populations responded positively to the experimental and natural thinning of the canopy. At one site, the response was the result of understory canopy thinning. At the second site, the response was due to the natural death of a canopy tree. In light of the dramatic increase in fungal abundance following death of the canopy tree, we propose the Fungal Abundance Hypothesis as an additional approach to the management of endangered plant species. The removal of canopy trees in or adjacent to Isotria populations results in an increase in dead belowground biomass (i.e., roots of the dead canopy tree) that provides substrates for microbial growth, including orchid mycorrhizal fungi, that benefit Isotria.
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Affiliation(s)
- Dennis Whigham
- Smithsonian Environmental Research Center, 647 Contees Wharf Road, Edgewater, MD 21037, USA; (M.M.); (H.B.)
- Correspondence: ; Tel.: +1-443-482-2226
| | - Melissa McCormick
- Smithsonian Environmental Research Center, 647 Contees Wharf Road, Edgewater, MD 21037, USA; (M.M.); (H.B.)
| | - Hope Brooks
- Smithsonian Environmental Research Center, 647 Contees Wharf Road, Edgewater, MD 21037, USA; (M.M.); (H.B.)
| | - Brian Josey
- Center for Environmental Management of Military Lands (CEMML), Colorado State University, Fort A. P. Hill, VA 22427, USA;
| | - Robert Floyd
- Headquarters Department of the Army, Washington, DC 20001, USA;
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Oktalira FT, May TW, Dearnaley JDW, Linde CC. Seven new Serendipita species associated with Australian terrestrial orchids. Mycologia 2021; 113:968-987. [PMID: 34338610 DOI: 10.1080/00275514.2021.1919848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Serendipita is one of the main fungal genera that form mutualistic associations with species of orchids (Orchidaceae). Here, seven new Serendipita species associated with various Australian orchid genera are described. These Serendipita species were originally characterized by multilocus DNA sequence species delimitation analyses (three mtDNA and four nuclear genes) and confirmed as distinct with addition of further isolates and reanalysis of nuc rDNA internal transcribed spacer region ITS1-5.8S-ITS2 (ITS) and nuc 28S rDNA (28S). Culture morphology and microscopic features are presented for each species, three of which are binucleate and four multinucleate. For the ITS region, the seven species have within-species sequence divergence between 1.07% and 4.31%, and all but one of the species pairs is separated by interspecific divergence of at least 4.35%. The newly described Serendipita species, S. australiana, S. communis, S. occidentalis, S. rarihospitum, S. secunda, S. talbotii, and S. warcupii, are shown to be separate species from S. vermifera on the basis of comparison against a sequence from the type. Isolates originally identified by Warcup as Sebacina "vermifera" from Caladenia orchids are revised and shown to belong to three of the species newly described here. Some non-Caladenia isolates identified by Warcup as S. "vermifera" are also shown to be non-conspecific with the type of S. vermifera. On the basis of ITS sequences, 346 isolates from 26 other studies, previously identified under provisional designations, are accommodated under the novel species. The species of Serendipta described here associate with the Australian orchid genera Caladenia, Cyanicula, Elythranthera, Ericksonella, Eriochilus, Glossodia, and Pheladenia. Most of the novel Serendipita species occur widely across Australia, often with widely distributed hosts, but one species, Serendipita rarihospitum, associates with narrowly distributed orchid species.
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Affiliation(s)
- Fitria T Oktalira
- Ecology and Evolution, Research School of Biology, College of Science, The Australian National University, Canberra, ACT 2601, Australia
| | - Tom W May
- Royal Botanic Gardens Victoria, Birdwood Avenue, Melbourne, VIC 3004, Australia
| | - John D W Dearnaley
- Centre for Crop Health, The University of Southern Queensland, Toowoomba, Queensland 4350, Australia
| | - Celeste C Linde
- Ecology and Evolution, Research School of Biology, College of Science, The Australian National University, Canberra, ACT 2601, Australia
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Zhao DK, Selosse MA, Wu L, Luo Y, Shao SC, Ruan YL. Orchid Reintroduction Based on Seed Germination-Promoting Mycorrhizal Fungi Derived From Protocorms or Seedlings. FRONTIERS IN PLANT SCIENCE 2021; 12:701152. [PMID: 34276753 PMCID: PMC8278863 DOI: 10.3389/fpls.2021.701152] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 06/04/2021] [Indexed: 06/13/2023]
Abstract
Orchids are among the most endangered in the plant kingdom. Lack of endosperm in their seeds renders orchids to depend on nutrients provided by orchid mycorrhizal fungi (OMF) for seed germination and seedling formation in the wild. OMF that parasitize in germination seeds is an essential element for orchid seedling formation, which can also help orchid reintroduction. Considering the limitations of the previous orchid reintroduction technology based on seed germination-promoting OMF (sgOMF) sourced from orchid roots, an innovative approach is proposed here in which orchid seeds are directly co-sown with sgOMF carrying ecological specificity from protocorms/seedlings. Based on this principle, an integrative and practical procedure concerning related ecological factors is further raised for re-constructing long-term and self-sustained orchid populations. We believe that this new approach will benefit the reintroduction of endangered orchids in nature.
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Affiliation(s)
- Da-Ke Zhao
- Biocontrol Engineering Research Center of Plant Disease and Pest, Biocontrol Engineering Research Center of Crop Disease and Pest, School of Ecology and Environmental Science, Yunnan University, Kunming, China
| | - Marc-André Selosse
- Département Systématique et Evolution, UMR 7205 ISYEB, Muséum National d'Histoire Naturelle, Paris, France
- Faculty of Biology, University of Gdansk, Gdansk, Poland
| | - Limin Wu
- Agriculture and Food, Commonwealth Scientific and Industrial Research Organisation, Canberra, ACT, Australia
| | - Yan Luo
- Gardening and Horticulture Department, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, China
| | - Shi-Cheng Shao
- Gardening and Horticulture Department, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, China
| | - Yong-Ling Ruan
- Australia-China Research Centre for Crop Improvement, School of Environmental and Life Sciences, The University of Newcastle, Callaghan, NSW, Australia
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Protocorm-Supporting Fungi Are Retained in Roots of Mature Tipularia discolor Orchids as Mycorrhizal Fungal Diversity Increases. PLANTS 2021; 10:plants10061251. [PMID: 34202964 PMCID: PMC8233912 DOI: 10.3390/plants10061251] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/16/2021] [Revised: 06/17/2021] [Accepted: 06/17/2021] [Indexed: 11/20/2022]
Abstract
Mycorrhizal fungi are critical to understanding the distribution patterns of many plants, but they are especially important for orchids. Some orchids may change the mycorrhizal fungi they use through their lives, either in response to changes in abiotic or biotic conditions, or as a result of ontogenetic changes that alter the orchid’s need for fungal nutrition. The temperate terrestrial orchid Tipularia discolor germinates only on decomposing wood, but often persists well after the wood has completely decomposed and has been incorporated into the soil. We used PCR and Sanger sequencing to ask: (1) Do mature T. discolor retain protocorm fungi or are protocorm and adult mycorrhizal fungi mutually exclusive? (2) Are protocorm fungi limited to areas with decomposing wood? (3) Does the abundance of protocorm fungi in the substrate differ between decomposing wood and bare soil? We found that T. discolor retained protocorm fungi into maturity, regardless of whether they were growing in persistent decomposing wood or soil. Protocorm fungi were not restricted to decomposing wood but were more common and abundant in it. We conclude that the mycorrhizal fungi associated with T. discolor change during the ontogeny of individuals. These results highlight the importance of assessing protocorm fungi, in addition to mycorrhizal fungi associating with adult orchids, to understand the conditions needed for orchid germination, growth, and reproduction.
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Fungal diversity driven by bark features affects phorophyte preference in epiphytic orchids from southern China. Sci Rep 2021; 11:11287. [PMID: 34050223 PMCID: PMC8163780 DOI: 10.1038/s41598-021-90877-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Accepted: 05/17/2021] [Indexed: 11/17/2022] Open
Abstract
Epiphytic orchids exhibit varying degrees of phorophyte tree specificity. We performed a pilot study to investigate why epiphytic orchids prefer or avoid certain trees. We selected two orchid species, Panisea uniflora and Bulbophyllum odoratissimum co-occurring in a forest habitat in southern China, where they showed a specific association with Quercus yiwuensis and Pistacia weinmannifolia trees, respectively. We analysed a number of environmental factors potentially influencing the relationship between orchids and trees. Difference in bark features, such as water holding capacity and pH were recorded between Q. yiwuensis and P. weinmannifolia, which could influence both orchid seed germination and fungal diversity on the two phorophytes. Morphological and molecular culture-based methods, combined with metabarcoding analyses, were used to assess fungal communities associated with studied orchids and trees. A total of 162 fungal species in 74 genera were isolated from bark samples. Only two genera, Acremonium and Verticillium, were shared by the two phorophyte species. Metabarcoding analysis confirmed the presence of significantly different fungal communities on the investigated tree and orchid species, with considerable similarity between each orchid species and its host tree, suggesting that the orchid-host tree association is influenced by the fungal communities of the host tree bark.
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Li T, Wu S, Yang W, Selosse MA, Gao J. How Mycorrhizal Associations Influence Orchid Distribution and Population Dynamics. FRONTIERS IN PLANT SCIENCE 2021; 12:647114. [PMID: 34025695 PMCID: PMC8138319 DOI: 10.3389/fpls.2021.647114] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Accepted: 04/13/2021] [Indexed: 05/04/2023]
Abstract
Orchid distribution and population dynamics are influenced by a variety of ecological factors and the formation of holobionts, which play key roles in colonization and ecological community construction. Seed germination, seedling establishment, reproduction, and survival of orchid species are strongly dependent on orchid mycorrhizal fungi (OMF), with mycorrhizal cheating increasingly observed in photosynthetic orchids. Therefore, changes in the composition and abundance of OMF can have profound effects on orchid distribution and fitness. Network analysis is an important tool for the study of interactions between plants, microbes, and the environment, because of the insights that it can provide into the interactions and coexistence patterns among species. Here, we provide a comprehensive overview, systematically describing the current research status of the effects of OMF on orchid distribution and dynamics, phylogenetic signals in orchid-OMF interactions, and OMF networks. We argue that orchid-OMF associations exhibit complementary and specific effects that are highly adapted to their environment. Such specificity of associations may affect the niche breadth of orchid species and act as a stabilizing force in plant-microbe coevolution. We postulate that network analysis is required to elucidate the functions of fungal partners beyond their effects on germination and growth. Such studies may lend insight into the microbial ecology of orchids and provide a scientific basis for the protection of orchids under natural conditions in an efficient and cost-effective manner.
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Affiliation(s)
- Taiqiang Li
- Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology, Yunnan University, Kunming, China
- Laboratory of Ecology and Evolutionary Biology, Yunnan University, Kunming, China
| | - Shimao Wu
- Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology, Yunnan University, Kunming, China
- Laboratory of Ecology and Evolutionary Biology, Yunnan University, Kunming, China
| | - Wenke Yang
- Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology, Yunnan University, Kunming, China
- Laboratory of Ecology and Evolutionary Biology, Yunnan University, Kunming, China
| | - Marc-André Selosse
- Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology, Yunnan University, Kunming, China
- Laboratory of Ecology and Evolutionary Biology, Yunnan University, Kunming, China
- Institut de Systématique, Évolution, Biodiversité, UMR 7205, CNRS, MNHN, UPMC, EPHE, Muséum National d’Histoire Naturelle, Sorbonne Universités, Paris, France
- Department of Plant Taxonomy and Nature Conservation, Faculty of Biology, University of Gdańsk, Gdańsk, Poland
| | - Jiangyun Gao
- Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology, Yunnan University, Kunming, China
- Laboratory of Ecology and Evolutionary Biology, Yunnan University, Kunming, China
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Li T, Yang W, Wu S, Selosse MA, Gao J. Progress and Prospects of Mycorrhizal Fungal Diversity in Orchids. FRONTIERS IN PLANT SCIENCE 2021; 12:646325. [PMID: 34025694 PMCID: PMC8138444 DOI: 10.3389/fpls.2021.646325] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2020] [Accepted: 04/12/2021] [Indexed: 05/03/2023]
Abstract
Orchids form mycorrhizal symbioses with fungi in natural habitats that affect their seed germination, protocorm growth, and adult nutrition. An increasing number of studies indicates how orchids gain mineral nutrients and sometime even organic compounds from interactions with orchid mycorrhizal fungi (OMF). Thus, OMF exhibit a high diversity and play a key role in the life cycle of orchids. In recent years, the high-throughput molecular identification of fungi has broadly extended our understanding of OMF diversity, revealing it to be a dynamic outcome co-regulated by environmental filtering, dispersal restrictions, spatiotemporal scales, biogeographic history, as well as the distribution, selection, and phylogenetic spectrum width of host orchids. Most of the results show congruent emerging patterns. Although it is still difficult to extend them to all orchid species or geographical areas, to a certain extent they follow the "everything is everywhere, but the environment selects" rule. This review provides an extensive understanding of the diversity and ecological dynamics of orchid-fungal association. Moreover, it promotes the conservation of resources and the regeneration of rare or endangered orchids. We provide a comprehensive overview, systematically describing six fields of research on orchid-fungal diversity: the research methods of orchid-fungal interactions, the primer selection in high-throughput sequencing, the fungal diversity and specificity in orchids, the difference and adaptability of OMF in different habitats, the comparison of OMF in orchid roots and soil, and the spatiotemporal variation patterns of OMF. Further, we highlight certain shortcomings of current research methodologies and propose perspectives for future studies. This review emphasizes the need for more information on the four main ecological processes: dispersal, selection, ecological drift, and diversification, as well as their interactions, in the study of orchid-fungal interactions and OMF community structure.
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Affiliation(s)
- Taiqiang Li
- Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology, Yunnan University, Kunming, China
- Laboratory of Ecology and Evolutionary Biology, Yunnan University, Kunming, China
| | - Wenke Yang
- Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology, Yunnan University, Kunming, China
- Laboratory of Ecology and Evolutionary Biology, Yunnan University, Kunming, China
| | - Shimao Wu
- Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology, Yunnan University, Kunming, China
- Laboratory of Ecology and Evolutionary Biology, Yunnan University, Kunming, China
| | - Marc-André Selosse
- Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology, Yunnan University, Kunming, China
- Laboratory of Ecology and Evolutionary Biology, Yunnan University, Kunming, China
- Institut de Systématique, Évolution, Biodiversité, UMR 7205, CNRS, MNHN, UPMC, EPHE, Muséum National d’Histoire Naturelle, Sorbonne Universités, Paris, France
- Department of Plant Taxonomy and Nature Conservation, Faculty of Biology, University of Gdańsk, Gdańsk, Poland
| | - Jiangyun Gao
- Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology, Yunnan University, Kunming, China
- Laboratory of Ecology and Evolutionary Biology, Yunnan University, Kunming, China
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Kaur J, Phillips C, Sharma J. Host population size is linked to orchid mycorrhizal fungal communities in roots and soil, which are shaped by microenvironment. MYCORRHIZA 2021; 31:17-30. [PMID: 33113039 DOI: 10.1007/s00572-020-00993-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2020] [Accepted: 10/12/2020] [Indexed: 05/04/2023]
Abstract
Interaction with orchid mycorrhizal fungi (OMF) is essential to all members of the Orchidaceae, yet we know little about whether or how OMF abundances in substrates shape orchid populations. While root-associated OMF diversity is catalogued frequently, technological constraints have impeded the assessments of OMF communities in substrates until recently, thereby limiting the ability to link OMF communities in a habitat to population responses. Furthermore, there is some evidence that edaphic and microclimatic conditions impact OMF in soil, yet we lack an understanding of the coupled influences of abiotic environment and OMF structure on orchid population dynamics. To discover the linkages between abiotic environment, OMF community structure, and population size, we characterized the microclimatic conditions, soil physicochemistry, and OMF communities hosted by roots and soil across large and small populations of a terrestrial orchid endemic to California Floristic Province in North America. By using high-throughput sequencing of the ITS2 region of nrDNA amplified from root and soil DNAs, we determined that both roots and soil of larger populations, which were high in phosphorus but low in zinc, organic matter, and silt, were dominated by Tulasnellaceae OTUs. In comparison, roots and soil from smaller populations of the orchid hosted higher relative abundances of the Ceratobasidiaceae. In this multiyear, range-wide study that simultaneously measured habitat environmental conditions, and soil and root OMF communities, our results suggest that soil chemistry is clearly linked to soil and root OMF communities, which then likely alter and shape orchid populations.
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Affiliation(s)
- Jaspreet Kaur
- Department of Plant and Soil Science, Texas Tech University, Lubbock, TX, USA.
| | - Caleb Phillips
- Department of Biological Sciences, Texas Tech University, Lubbock, TX, USA
| | - Jyotsna Sharma
- Department of Plant and Soil Science, Texas Tech University, Lubbock, TX, USA
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Zeng X, Diao H, Ni Z, Shao L, Jiang K, Hu C, Huang Q, Huang W. Temporal Variation in Community Composition of Root Associated Endophytic Fungi and Carbon and Nitrogen Stable Isotope Abundance in Two Bletilla Species (Orchidaceae). PLANTS (BASEL, SWITZERLAND) 2020; 10:E18. [PMID: 33374219 PMCID: PMC7824424 DOI: 10.3390/plants10010018] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 12/21/2020] [Accepted: 12/22/2020] [Indexed: 11/16/2022]
Abstract
Mycorrhizae are an important energy source for orchids that may replace or supplement photosynthesis. Most mature orchids rely on mycorrhizae throughout their life cycles. However, little is known about temporal variation in root endophytic fungal diversity and their trophic functions throughout whole growth periods of the orchids. In this study, the community composition of root endophytic fungi and trophic relationships between root endophytic fungi and orchids were investigated in Bletilla striata and B. ochracea at different phenological stages using stable isotope natural abundance analysis combined with molecular identification analysis. We identified 467 OTUs assigned to root-associated fungal endophytes, which belonged to 25 orders in 10 phyla. Most of these OTUs were assigned to saprotroph (143 OTUs), pathotroph-saprotroph (63 OTUs) and pathotroph-saprotroph-symbiotroph (18 OTUs) using FunGuild database. Among these OTUs, about 54 OTUs could be considered as putative species of orchid mycorrhizal fungi (OMF). For both Bletilla species, significant temporal variation was observed in the diversity of root endophytic fungi. The florescence and emergence periods had higher fungal community richness of total species and endemic species than did other periods. Both Bletilla species were dominated by Agaricomycetes and Basidiomycota fungi throughout the whole year; however, their abundances varied between two Bletilla species and among phenological stages. Meanwhile, the ranges of 13C and 15N natural abundance were also highly dynamic across all growth stages of Bletilla species. Compared with the surrounding autotrophic plants, significant 13C enrichments (ε13C) were found across all phenological stages, while significant 15N enrichment in the florescence period and strong 15N depletion during the fruiting period were found for both Bletilla species. We can deduce that both Bletilla species obtained carbon from root endophytic fungi during the whole year. Additionally, the temporal varying tendency of root endophytic fungal diversity was consistent with 13C enrichments, which was also accord with the nutritional requirement of plant.
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Affiliation(s)
- Xinhua Zeng
- Shanghai Chenshan Plant Science Research Center, Chinese Academy of Sciences, Chenshan Botanical Garden, Shanghai 201620, China; (X.Z.); (H.D.); (Z.N.); (L.S.); (K.J.); (C.H.)
| | - Haixin Diao
- Shanghai Chenshan Plant Science Research Center, Chinese Academy of Sciences, Chenshan Botanical Garden, Shanghai 201620, China; (X.Z.); (H.D.); (Z.N.); (L.S.); (K.J.); (C.H.)
| | - Ziyi Ni
- Shanghai Chenshan Plant Science Research Center, Chinese Academy of Sciences, Chenshan Botanical Garden, Shanghai 201620, China; (X.Z.); (H.D.); (Z.N.); (L.S.); (K.J.); (C.H.)
| | - Li Shao
- Shanghai Chenshan Plant Science Research Center, Chinese Academy of Sciences, Chenshan Botanical Garden, Shanghai 201620, China; (X.Z.); (H.D.); (Z.N.); (L.S.); (K.J.); (C.H.)
| | - Kai Jiang
- Shanghai Chenshan Plant Science Research Center, Chinese Academy of Sciences, Chenshan Botanical Garden, Shanghai 201620, China; (X.Z.); (H.D.); (Z.N.); (L.S.); (K.J.); (C.H.)
| | - Chao Hu
- Shanghai Chenshan Plant Science Research Center, Chinese Academy of Sciences, Chenshan Botanical Garden, Shanghai 201620, China; (X.Z.); (H.D.); (Z.N.); (L.S.); (K.J.); (C.H.)
| | - Qingjun Huang
- Shanghai Institute of Technology, Shanghai 201418, China;
| | - Weichang Huang
- Shanghai Chenshan Plant Science Research Center, Chinese Academy of Sciences, Chenshan Botanical Garden, Shanghai 201620, China; (X.Z.); (H.D.); (Z.N.); (L.S.); (K.J.); (C.H.)
- College of Landscape Architecture, Fujian Agriculture and Forestry University, Fuzhou 350002, China
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Herrera-Rus I, Pastor JE, Juan R. Fungal colonization associated with phenological stages of a photosynthetic terrestrial temperate orchid from the Southern Iberian Peninsula. JOURNAL OF PLANT RESEARCH 2020; 133:807-825. [PMID: 32968931 DOI: 10.1007/s10265-020-01225-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Accepted: 09/14/2020] [Indexed: 05/20/2023]
Abstract
Fungal endophytes, both mycorrhizal and non-mycorrhizal, are involved in the development of the life cycle of orchids, providing potential beneficial relationships. Here, we assess the succession of changes in the diversity of fungal symbionts associated with a terrestrial temperate orchid species, Anacamptis morio subsp. champagneuxii, over three phenological stages: developed leaves but no stem elongation, flowering, and fruiting. Fungi endophyte associated with roots were obtained by culture in sterile conditions. A total of 18 morphotypes-one Mortierellomycota, two Basidiomycota and 15 Ascomycota-were differentiated, and were also characterized using PCR and DNA sequencing techniques. Only three of the 18 OTUs are shared among the three phenological stages examined: Westerdykella sp., a member of Ceratobasidiaceae, and Fusarium oxysporum, representing a relative abundance of between 28% (fruiting) to 41% (flowering). Our research confirmed that fungal symbionts varied among the different phenological stages examined, the peak of endophyte diversity appearing in the flowering stage. The availability of a diverse mycobiota seems to be important for the survival of orchid plants because it may cover particular physiological needs, and knowledge concerning this mycobiota is of special relevance in the establishment of reliable conservation programmes.
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Affiliation(s)
- Irene Herrera-Rus
- Departamento de Biología Vegetal y Ecología, Facultad de Farmacia, Universidad de Sevilla, Profesor García González, 2, 41012, Sevilla, Spain
| | - Julio E Pastor
- Departamento de Biología Vegetal y Ecología, Facultad de Biología, Universidad de Sevilla, Reina Mercedes, 6, 41012, Sevilla, Spain
| | - Rocío Juan
- Departamento de Biología Vegetal y Ecología, Facultad de Farmacia, Universidad de Sevilla, Profesor García González, 2, 41012, Sevilla, Spain.
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Mujica MI, Cisternas M, Claro A, Simunovic M, Pérez F. Nutrients and fungal identity affect the outcome of symbiotic germination in Bipinnula fimbriata (Orchidaceae). Symbiosis 2020. [DOI: 10.1007/s13199-020-00737-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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24
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Reiter N, Phillips RD, Swarts ND, Wright M, Holmes G, Sussmilch FC, Davis BJ, Whitehead MR, Linde CC. Specific mycorrhizal associations involving the same fungal taxa in common and threatened Caladenia (Orchidaceae): implications for conservation. ANNALS OF BOTANY 2020; 126:943-955. [PMID: 32574356 PMCID: PMC7539350 DOI: 10.1093/aob/mcaa116] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Accepted: 06/18/2020] [Indexed: 05/04/2023]
Abstract
BACKGROUND AND AIMS In orchid conservation, quantifying the specificity of mycorrhizal associations, and establishing which orchid species use the same fungal taxa, is important for sourcing suitable fungi for symbiotic propagation and selecting sites for conservation translocation. For Caladenia subgenus Calonema (Orchidaceae), which contains 58 threatened species, we ask the following questions. (1) How many taxa of Serendipita mycorrhizal fungi do threatened species of Caladenia associate with? (2) Do threatened Caladenia share orchid mycorrhizal fungi with common Caladenia? (3) How geographically widespread are mycorrhizal fungi associated with Caladenia? METHODS Fungi were isolated from 127 Caladenia species followed by DNA sequencing of the internal transcibed spacer (ITS) sequence locus. We used a 4.1-6 % sequence divergence cut-off range to delimit Serendipita operational taxonomic units (OTUs). We conducted trials testing the ability of fungal isolates to support germination and plant growth. A total of 597 Serendipita isolates from Caladenia, collected from across the Australian continent, were used to estimate the geographic range of OTUs. KEY RESULTS Across the genus, Caladenia associated with ten OTUs of Serendipita (Serendipitaceae) mycorrhizal fungi. Specificity was high, with 19 of the 23 threatened Caladenia species sampled in detail associating solely with OTU A, which supported plants from germination to adulthood. The majority of populations of Caladenia associated with one OTU per site. Fungal sharing was extensive, with 62 of the 79 Caladenia sampled in subgenus Calonema associating with OTU A. Most Serendipita OTUs were geographically widespread. CONCLUSIONS Mycorrhizal fungi can be isolated from related common species to propagate threatened Caladenia. Because of high specificity of most Caladenia species, only small numbers of OTUs typically need to be considered for conservation translocation. When selecting translocation sites, the geographic range of the fungi is not a limiting factor, and using related Caladenia species to infer the presence of suitable fungal OTUs may be feasible.
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Affiliation(s)
- Noushka Reiter
- Royal Botanic Gardens Victoria, Corner of Ballarto Road and Botanic Drive, Cranbourne, Victoria, Australia
- Ecology and Evolution, Research School of Biology, ANU College of Science, RN Robertson Building, 46 Sullivans Creek Road, The Australian National University, Canberra, ACT, Australia
| | - Ryan D Phillips
- Ecology and Evolution, Research School of Biology, ANU College of Science, RN Robertson Building, 46 Sullivans Creek Road, The Australian National University, Canberra, ACT, Australia
- Department of Ecology, Environment and Evolution, La Trobe University, Melbourne, Victoria, Australia
- Kings Park Science, Department of Biodiversity Conservation and Attractions, Kattidj Close Kings Park, WA, Australia
| | - Nigel D Swarts
- Royal Tasmanian Botanical Gardens, Queens Domain, Hobart, Tasmania, Australia
- Tasmanian Institute of Agriculture, University of Tasmania, Sandy Bay, Tasmania, Australia
| | - Magali Wright
- Royal Tasmanian Botanical Gardens, Queens Domain, Hobart, Tasmania, Australia
| | - Gareth Holmes
- Royal Botanic Gardens Victoria, Corner of Ballarto Road and Botanic Drive, Cranbourne, Victoria, Australia
| | - Frances C Sussmilch
- Kings Park Science, Department of Biodiversity Conservation and Attractions, Kattidj Close Kings Park, WA, Australia
| | - Belinda J Davis
- Kings Park Science, Department of Biodiversity Conservation and Attractions, Kattidj Close Kings Park, WA, Australia
| | - Michael R Whitehead
- School of BioSciences, The University of Melbourne, Parkville, Victoria, Australia
| | - Celeste C Linde
- Ecology and Evolution, Research School of Biology, ANU College of Science, RN Robertson Building, 46 Sullivans Creek Road, The Australian National University, Canberra, ACT, Australia
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Wraith J, Norman P, Pickering C. Orchid conservation and research: An analysis of gaps and priorities for globally Red Listed species. AMBIO 2020; 49:1601-1611. [PMID: 31960279 PMCID: PMC7413930 DOI: 10.1007/s13280-019-01306-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 10/29/2019] [Accepted: 12/06/2019] [Indexed: 06/10/2023]
Abstract
Orchids are among the most threatened taxa globally due to increasing anthropogenic threats, inherent rarity and specific conservation needs. But what are the global research and conservation priorities for this charismatic group of plants? Using information for 595 orchids on the IUCN Red List, we reviewed past research and identified key research and conservation priorities. These included understanding threats, monitoring orchid populations and habitats, species management in ex situ conservation, genome resource banks and artificial propagation, land and habitat protection and education and awareness through communication. Based on the available data, we recommend future orchid conservation and research should focus on the current gaps in knowledge and practice including monitoring population trends and distributions, ecology, threats, protection and management of species and their habitats and increasing education and awareness.
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Affiliation(s)
- Jenna Wraith
- Griffith School of Environment, Environmental Futures Research Institute, Griffith University, Parklands Drive, Southport, Gold Coast, QLD 4222 Australia
| | - Patrick Norman
- Griffith School of Environment, Environmental Futures Research Institute, Griffith University, Parklands Drive, Southport, Gold Coast, QLD 4222 Australia
| | - Catherine Pickering
- Griffith School of Environment, Environmental Futures Research Institute, Griffith University, Parklands Drive, Southport, Gold Coast, QLD 4222 Australia
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Chen S, Dai J, Song X, Jiang X, Zhao Q, Sun C, Chen C, Chen N, Han B. Endophytic Microbiota Comparison of Dendrobium huoshanense Root and Stem in Different Growth Years. PLANTA MEDICA 2020; 86:967-975. [PMID: 31766070 DOI: 10.1055/a-1046-1022] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The endophytic microbiome in medicinal plants is rich and diverse, but few studies have followed the endophytic microbiome of medicinal plants in different tissues with their growth. In this study, we examined the endophytic bacterial and fungal community structures associated with both the stem and root compartments of Dendrobium huoshanense at different growth years via high-throughput sequencing of 16S rRNA genes and nrDNA fragments of internal transcribed spacer regions. Results indicated that more diverse prokaryotic and fungal operational taxonomic units were detected in roots than in stems, and the alpha diversity of endophytic prokaryotic significantly differed among the 1-, 2-, and 3-year-old roots. The dominant bacterial phyla Proteobacteria Firmicutes, Actinobacteria, Bacteroidetes, and Acidobacteria, and fungal phyla Ascomycota, Basidiomycota, and Ascomycota were detected in the stems and roots with 3 growth years. Moreover, linear discriminant effect size analysis revealed 138 differentially abundant taxonomic clades in the bacterial level, and 197 in the fungal level in six groups. Our results provide evidence for endophytic microbiota communities depending on the tissues and growth years of D. huoshanense. The results from this study should be useful to better understand medicinal plant-microbe interactions.
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Affiliation(s)
- Shaotong Chen
- Department of Biological and Pharmaceutical Engineering, West Anhui University, Lu'an, China
- Department of Pharmacy, Anhui University of Chinese Medicine, He'fei, China
| | - Jun Dai
- Department of Biological and Pharmaceutical Engineering, West Anhui University, Lu'an, China
- Anhui Province Traditional Chinese Medicine Resource Protection and Sustainable Utilization Engineering Laboratory, Lu'an, China
| | - Xiangwen Song
- Department of Biological and Pharmaceutical Engineering, West Anhui University, Lu'an, China
- Anhui Province Traditional Chinese Medicine Resource Protection and Sustainable Utilization Engineering Laboratory, Lu'an, China
| | - Xueping Jiang
- Department of Biological and Pharmaceutical Engineering, West Anhui University, Lu'an, China
- Anhui Province Traditional Chinese Medicine Resource Protection and Sustainable Utilization Engineering Laboratory, Lu'an, China
| | - Qun Zhao
- Department of Biological and Pharmaceutical Engineering, West Anhui University, Lu'an, China
- Anhui Province Traditional Chinese Medicine Resource Protection and Sustainable Utilization Engineering Laboratory, Lu'an, China
| | - Chuanbo Sun
- Department of Biological and Pharmaceutical Engineering, West Anhui University, Lu'an, China
- Anhui Province Traditional Chinese Medicine Resource Protection and Sustainable Utilization Engineering Laboratory, Lu'an, China
| | - Cunwu Chen
- Department of Biological and Pharmaceutical Engineering, West Anhui University, Lu'an, China
- Anhui Province Traditional Chinese Medicine Resource Protection and Sustainable Utilization Engineering Laboratory, Lu'an, China
| | - Naifu Chen
- Department of Biological and Pharmaceutical Engineering, West Anhui University, Lu'an, China
- Anhui Province Traditional Chinese Medicine Resource Protection and Sustainable Utilization Engineering Laboratory, Lu'an, China
| | - Bangxing Han
- Department of Biological and Pharmaceutical Engineering, West Anhui University, Lu'an, China
- Anhui Province Traditional Chinese Medicine Resource Protection and Sustainable Utilization Engineering Laboratory, Lu'an, China
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Phillips RD, Reiter N, Peakall R. Orchid conservation: from theory to practice. ANNALS OF BOTANY 2020; 126:345-362. [PMID: 32407498 PMCID: PMC7424752 DOI: 10.1093/aob/mcaa093] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Accepted: 05/07/2020] [Indexed: 05/21/2023]
Abstract
BACKGROUND Given the exceptional diversity of orchids (26 000+ species), improving strategies for the conservation of orchids will benefit a vast number of taxa. Furthermore, with rapidly increasing numbers of endangered orchids and low success rates in orchid conservation translocation programmes worldwide, it is evident that our progress in understanding the biology of orchids is not yet translating into widespread effective conservation. SCOPE We highlight unusual aspects of the reproductive biology of orchids that can have important consequences for conservation programmes, such as specialization of pollination systems, low fruit set but high seed production, and the potential for long-distance seed dispersal. Further, we discuss the importance of their reliance on mycorrhizal fungi for germination, including quantifying the incidence of specialized versus generalized mycorrhizal associations in orchids. In light of leading conservation theory and the biology of orchids, we provide recommendations for improving population management and translocation programmes. CONCLUSIONS Major gains in orchid conservation can be achieved by incorporating knowledge of ecological interactions, for both generalist and specialist species. For example, habitat management can be tailored to maintain pollinator populations and conservation translocation sites selected based on confirmed availability of pollinators. Similarly, use of efficacious mycorrhizal fungi in propagation will increase the value of ex situ collections and likely increase the success of conservation translocations. Given the low genetic differentiation between populations of many orchids, experimental genetic mixing is an option to increase fitness of small populations, although caution is needed where cytotypes or floral ecotypes are present. Combining demographic data and field experiments will provide knowledge to enhance management and translocation success. Finally, high per-fruit fecundity means that orchids offer powerful but overlooked opportunities to propagate plants for experiments aimed at improving conservation outcomes. Given the predictions of ongoing environmental change, experimental approaches also offer effective ways to build more resilient populations.
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Affiliation(s)
- Ryan D Phillips
- Department of Ecology, Environment and Evolution, La Trobe University, Melbourne, Victoria, Australia
- Kings Park Science, Department of Biodiversity Conservation and Attractions, Kings Park, WA, Australia
- Ecology and Evolution, Research School of Biology, The Australian National University, Canberra, ACT, Australia
| | - Noushka Reiter
- Ecology and Evolution, Research School of Biology, The Australian National University, Canberra, ACT, Australia
- Royal Botanic Gardens Victoria, Corner of Ballarto Road and Botanic Drive, Cranbourne, VIC, Australia
| | - Rod Peakall
- Ecology and Evolution, Research School of Biology, The Australian National University, Canberra, ACT, Australia
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28
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Downing JL, Liu H, McCormick MK, Arce J, Alonso D, Lopez‐Perez J. Generalized mycorrhizal interactions and fungal enemy release drive range expansion of orchids in southern Florida. Ecosphere 2020. [DOI: 10.1002/ecs2.3228] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Affiliation(s)
- Jason L. Downing
- International Center for Tropical Botany Florida International University 11200 8th Street Miami Florida33199USA
- Fairchild Tropical Botanic Garden 10901 Old Cutler Road Coral Gables Florida33156USA
| | - Hong Liu
- International Center for Tropical Botany Florida International University 11200 8th Street Miami Florida33199USA
- Fairchild Tropical Botanic Garden 10901 Old Cutler Road Coral Gables Florida33156USA
| | - Melissa K. McCormick
- Smithsonian Institution Smithsonian Environmental Research Center 647 Contees Wharf Road Edgewater Maryland21037USA
| | - Jay Arce
- International Center for Tropical Botany Florida International University 11200 8th Street Miami Florida33199USA
- Fairchild Tropical Botanic Garden 10901 Old Cutler Road Coral Gables Florida33156USA
| | - Dailen Alonso
- International Center for Tropical Botany Florida International University 11200 8th Street Miami Florida33199USA
| | - Jorge Lopez‐Perez
- International Center for Tropical Botany Florida International University 11200 8th Street Miami Florida33199USA
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Vogt-Schilb H, Těšitelová T, Kotilínek M, Sucháček P, Kohout P, Jersáková J. Altered rhizoctonia assemblages in grasslands on ex-arable land support germination of mycorrhizal generalist, not specialist orchids. THE NEW PHYTOLOGIST 2020; 227:1200-1212. [PMID: 32285948 DOI: 10.1111/nph.16604] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Accepted: 04/01/2020] [Indexed: 05/03/2023]
Abstract
Species-rich seminatural grasslands in Central Europe have suffered a dramatic loss of biodiversity due to conversion to arable land, but vast areas are being restored. Population recovery of orchids, which depend on mycorrhizal fungi for germination, is however limited. We hypothesised that ploughing and fertilisation caused shifts in orchid mycorrhizal communities in soil and restricted orchid germination. We examined edaphic conditions in 60 restored and seminatural grasslands, and germination success in 10 restored grasslands. Using a newly designed primer, we screened the composition of rhizoctonias in soil, seedlings and roots of seven orchid species. Seminatural and restored grasslands differed significantly in nutrient amounts and rhizoctonia assemblages in soil. While Serendipitaceae prevailed in seminatural grasslands with a higher organic matter content, Ceratobasidiaceae were more frequent in phosphorus-rich restored grasslands with increased abundance on younger restored sites. Tulasnellaceae displayed no preference. Germination success in restored grasslands differed significantly between orchid species; two mycorrhizal generalist species germinated with a broad range of rhizoctonias at most restored grasslands, while germination success of specialists was low. Past agricultural practices have a long-lasting effect on soil conditions and orchid mycorrhizal communities. Altered mycorrhizal availability may be the main reason for low germination success of specialist orchid species.
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Affiliation(s)
- Hélène Vogt-Schilb
- Faculty of Science, University of South Bohemia, Branišovská 1760, 37005, České Budějovice, Czech Republic
- CEFE, CNRS, EPHE, IRD, Université de Montpellier, Université Paul-Valéry Montpellier, 1919 Route de Mende, 34293, Montpellier, France
| | - Tamara Těšitelová
- Faculty of Science, University of South Bohemia, Branišovská 1760, 37005, České Budějovice, Czech Republic
| | - Milan Kotilínek
- Faculty of Science, University of South Bohemia, Branišovská 1760, 37005, České Budějovice, Czech Republic
| | - Pavel Sucháček
- Faculty of Science, University of South Bohemia, Branišovská 1760, 37005, České Budějovice, Czech Republic
| | - Petr Kohout
- Institute of Microbiology ASCR, Vídeňská 1083, 142 20, Prague 4 - Krč, Czech Republic
- Faculty of Science, Charles University, CZ-128 44, Prague 2, Czech Republic
| | - Jana Jersáková
- Faculty of Science, University of South Bohemia, Branišovská 1760, 37005, České Budějovice, Czech Republic
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30
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Crain BJ, Fernández M. Biogeographical analyses to facilitate targeted conservation of orchid diversity hotspots in Costa Rica. DIVERS DISTRIB 2020. [DOI: 10.1111/ddi.13062] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Affiliation(s)
- Benjamin J. Crain
- Department of Biology University of Puerto Rico‐Río Piedras San Juan Puerto Rico
- International Institute of Tropical ForestryJardín Botánico Sur San Juan Puerto Rico
| | - Melania Fernández
- Lankester Botanical Garden University of Costa Rica Cartago Costa Rica
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31
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Gao Y, Zhao Z, Li J, Liu N, Jacquemyn H, Guo S, Xing X. Do fungal associates of co-occurring orchids promote seed germination of the widespread orchid species Gymnadenia conopsea? MYCORRHIZA 2020; 30:221-228. [PMID: 32146514 DOI: 10.1007/s00572-020-00943-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Accepted: 02/27/2020] [Indexed: 05/04/2023]
Abstract
Interactions with mycorrhizal fungi have been increasingly recognized as one of the most important ecological factors determining the distribution and local abundance of orchids. While some orchid species may interact with a variety of fungal associates, others are more specific in their choice of mycorrhizal partners. Moreover, orchids that co-occur at a given site, often associate with different partners, possibly to avoid competition and to allow stable coexistence. However, whether differences in mycorrhizal partners directly affect seed germination and subsequent protocorm formation remains largely unknown. In this research, we used in vitro germination experiments to investigate to what extent seed germination and protocorm formation of Gymnadenia conopsea was affected by the origin and identity of fungal associates. Fungi were isolated from G. conopsea and three other co-occurring orchid species (Dactylorhiza viridis (Coeloglossum viride), Herminium monorchis, and Platanthera chlorantha). In total, eight fungal associates, belonging to Tulasnellaceae, Ceratobasidiaceae, and Serendipitaceae, were successfully isolated and cultured. While all eight fungal strains were able to promote early germination of G. conopsea seeds, only fungal strain GS2, a member of the Ceratobasidiaceae isolated from G. conopsea itself, was able to promote protocorm formation and subsequent growth to a seedling. Two other fungal strains isolated from G. conopsea only supported seed germination until the protocorm formation stage. The other five fungal strains isolated from the co-occurring orchid species did not support seed germination beyond the protocorm stage. We conclude that, although G. conopsea is considered a mycorrhizal generalist that associates with a wide range of fungi during its adult life, it requires specific fungi to promote protocorm formation and growth to a seedling.
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Affiliation(s)
- Yue Gao
- 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, Beijing, 100193, China
| | - Zeyu Zhao
- 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, Beijing, 100193, China
| | - Jiayao Li
- 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, Beijing, 100193, China
| | - Na Liu
- 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, Beijing, 100193, China
| | - Hans Jacquemyn
- KU Leuven, Department of Biology, Plant Conservation and Population Biology, B-3001, Leuven, Belgium
| | - Shunxing Guo
- 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, Beijing, 100193, China
| | - 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, Beijing, 100193, China.
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32
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Bell J, Yokoya K, Kendon JP, Sarasan V. Diversity of root-associated culturable fungi of Cephalanthera rubra (Orchidaceae) in relation to soil characteristics. PeerJ 2020; 8:e8695. [PMID: 32175192 PMCID: PMC7058101 DOI: 10.7717/peerj.8695] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2019] [Accepted: 02/05/2020] [Indexed: 11/30/2022] Open
Abstract
Cephalanthera rubra (L.) Rich., Red Helleborine, is a widespread orchid in Europe but known only from three very small populations in England. These populations are in decline with no natural seed setting for more than a decade. The species may become extinct in the UK soon unless viable strategies are in place for ex situ conservation, especially the use of symbiotic propagation. Because of the fragile nature of the populations in England mycorrhizal fungal diversity study is not feasible. Therefore, to understand the factors needed for healthy Red Helleborine populations, soil characteristics and diversity of culturable root-derived fungi of the populations from a small area in the Loire Valley in France were studied. The main objectives of the study were: (1) Which culturable mycorrhizal fungi associated with C. rubra roots and (2) To what extent is variation in fungal communities related to variation in soil characteristics? Here, we report a significant difference in diversity of culturable mycorrhizal and non-mycorrhizal fungi depending on soil pH and phosphorus content. Mycorrhizal associations were favoured by plants in locations with low soil nutrient availability and comparatively higher pH. Our study shows that mycorrhizal fungi, both ecto and endo, can be cultured from roots of plants at different maturity stages.
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Affiliation(s)
- Jake Bell
- Natural Capital and Plant Health, Royal Botanic Gardens, Kew, Richmond, Surrey, UK
| | - Kazutomo Yokoya
- Natural Capital and Plant Health, Royal Botanic Gardens, Kew, Richmond, Surrey, UK
| | - Jonathan P. Kendon
- Comparative Plant and Fungal Biology, Royal Botanic Gardens, Kew, Richmond, Surrey, UK
| | - Viswambharan Sarasan
- Natural Capital and Plant Health, Royal Botanic Gardens, Kew, Richmond, Surrey, UK
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33
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Figura T, Weiser M, Ponert J. Orchid seed sensitivity to nitrate reflects habitat preferences and soil nitrate content. PLANT BIOLOGY (STUTTGART, GERMANY) 2020; 22:21-29. [PMID: 31509637 DOI: 10.1111/plb.13044] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/01/2019] [Accepted: 08/22/2019] [Indexed: 05/04/2023]
Abstract
Orchids are distributed around the world, however, the factors shaping their specific distribution and habitat preferences are largely unknown. Moreover, many orchids are at risk of becoming threatened as landscapes change, sometimes declining without apparent reason. One important factor affecting plant distribution is nutrient levels in the environment. Nitrates can inhibit not only orchid growth and persistence, but also seed germination. We used in vitro axenic cultures to exactly determine the germination sensitivity of seven orchid species to nitrates and correlated this with soil properties of the natural sites and with the species' habitat preferences. We found high variation in response to nitrate between species. Orchids from oligotrophic habitats were highly sensitive, while orchids from more eutrophic habitats were almost insensitive. Sensitivity to nitrate was also associated with soil parameters that indicated a higher nitrification rate. Our results indicate that nitrate can affect orchid distribution via direct inhibition of seed germination. Nitrate levels in soils are increasing rapidly due to intensification of agricultural processes and concurrent soil pollution, and we propose this increase could cause a decline in some orchid species.
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Affiliation(s)
- T Figura
- Department of Experimental Plant Biology, Faculty of Science, Charles University, Prague, Czech Republic
- Institut de Systématique, Évolution, Biodiversité (ISYEB), Muséum national d'Histoire naturelle, CNRS, Sorbonne Université, Paris, France
| | - M Weiser
- Department of Botany, Faculty of Science, Charles University, Prague, Czech Republic
| | - J Ponert
- Department of Experimental Plant Biology, Faculty of Science, Charles University, Prague, Czech Republic
- Prague Botanical Garden, Prague, Czech Republic
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Izuddin M, Srivathsan A, Lee AL, Yam TW, Webb EL. Availability of orchid mycorrhizal fungi on roadside trees in a tropical urban landscape. Sci Rep 2019; 9:19528. [PMID: 31863015 PMCID: PMC6925147 DOI: 10.1038/s41598-019-56049-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Accepted: 11/24/2019] [Indexed: 12/02/2022] Open
Abstract
Urban expansion threatens biodiversity worldwide, therefore urban spaces need to be amenable to biodiversity conservation. On trees in urban environments, natural colonisation and successful translocation of epiphytic orchids are necessary to enhance urban biodiversity, and depend on the availability of compatible orchid mycorrhizal fungi (OMF). However, the extent of OMF presence and distribution, as well as niche requirements for the OMF, remain poorly studied. To identify and quantify OMF on urban trees as well as assess their suitability for native epiphytic orchids, we conducted high-throughput sequencing on tree bark and orchid root samples. OMF were detected at 60% of the study sites on 16% of 270 bark samples (from stem, fork, and branch microsites within each tree). OMF presence and richness on bark samples were related to multiple biophysical factors; in general, humus presence and precipitation levels were positively predictive of OMF presence and richness. We found Ceratobasidiaceae- and Serendipitaceae-associated OMF both on bark and within roots. Orchid species also showed differing mycorrhizal specificity. Sites associated with fungal genera Ceratobasidium, Rhizoctonia, and Serendipita were considered suitable habitats for seven orchid species. The results suggest that urban trees support OMF and are therefore suitable for native orchid species; however, OMF availability are largely constrained by biophysical factors. To maximise the likelihood of translocation success and consequent natural establishment, we propose that (micro)sites are screened for compatible OMF prior to any intervention.
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Affiliation(s)
- Muhammad Izuddin
- Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore, 117543, Singapore.
| | - Amrita Srivathsan
- Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore, 117543, Singapore
| | - Ai Lan Lee
- Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore, 117543, Singapore
| | - Tim Wing Yam
- Singapore Botanic Gardens, 1 Cluny Road, Singapore, 25956, Singapore
| | - Edward L Webb
- Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore, 117543, Singapore.
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35
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Oktalira FT, Whitehead MR, Linde CC. Mycorrhizal specificity in widespread and narrow-range distributed Caladenia orchid species. FUNGAL ECOL 2019. [DOI: 10.1016/j.funeco.2019.100869] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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36
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Kaur J, Andrews L, Sharma J. High specificity of a rare terrestrial orchid toward a rare fungus within the North American tallgrass prairie. Fungal Biol 2019; 123:895-904. [PMID: 31733732 DOI: 10.1016/j.funbio.2019.09.010] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Revised: 09/17/2019] [Accepted: 09/24/2019] [Indexed: 10/25/2022]
Abstract
The Orchidaceae are globally distributed and represent a diverse lineage of obligate mycotrophic plants. Given their dependence on symbiotic fungi for germination and/or plant development, fungal community structure in substrates is expected to influence the distribution and persistence of orchid species. Yet, simultaneous characterization of orchid mycorrhizal fungal (OMF) communities in roots and in soil is rarely reported. To explain the co-distributions of OMF in roots, orchid-occupied, and bulk soil, we characterized mycorrhizal fungi associated with Platanthera praeclara over multiple years across its entire natural distribution within the North American tallgrass prairie. Root derived OMF communities included 24 Ceratobasidiaceae and 7 Tulasnellaceae operational taxonomic units (OTUs) though the orchid exhibited high spatio-temporal specificity toward a single Ceratobasidiaceae OTU, which was strongly stable across population sizes and phenological stages of the sampled individuals. The preferred OMF OTUs were primarily restricted to orchid-occupied locations while infrequent or absent in bulk soil. Variation in soil OMF assemblies was explained most by soil moisture, magnesium, manganese, and clay. In this first study of coupled root and soil OMF communities across a threatened grassland ecosystem, we report a strong relationship, further nuanced by soil chemistry, between a rare fungus and a rare orchid.
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Affiliation(s)
- Jaspreet Kaur
- Department of Plant and Soil Science, Texas Tech University, Lubbock, TX, 79409, USA
| | - Lela Andrews
- Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ, 86011, USA
| | - Jyotsna Sharma
- Department of Plant and Soil Science, Texas Tech University, Lubbock, TX, 79409, USA.
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37
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Hemrová L, Kotilínek M, Konečná M, Paulič R, Jersáková J, Těšitelová T, Knappová J, Münzbergová Z. Identification of drivers of landscape distribution of forest orchids using germination experiment and species distribution models. Oecologia 2019; 190:411-423. [PMID: 31154510 DOI: 10.1007/s00442-019-04427-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Accepted: 05/28/2019] [Indexed: 10/26/2022]
Abstract
The family of orchids involves a number of critically endangered species. Understanding of drivers of their landscape distribution could provide a valuable insight into their decline. Our objectives were to develop models predicting distribution of selected orchid species-four co-occurring forest orchid species, Cephalanthera rubra, Epipactis atrorubens, E. helleborine, and Neottia nidus-avis-at a landscape scale using a wide range of habitat characteristics. Subsequently, we compared the model predictions with species occurrence and the results of the field germination experiment while considering two germination stages-asymbiotic (early stage) and symbiotic. And finally, we attempted to identify possible drivers of species' landscape distribution (i.e., dispersal, availability of habitat patches, or fungal associates). We have discovered that different habitat characteristics determined the distribution of different orchids. The species also differed in terms of availability of suitable habitat patches and patch occupancy (the highest being E. atrorubens with 80%). Landscape distribution of the species was primarily restricted by the availability of fungal associates (the most important factor for C. rubra) and by the availability of suitable habitat patches (the most important in case of N. nidus-avis). Despite expected easy dispersal of spores, orchid distribution seems to be limited by the availability of fungal associates in the landscape. In contrast, the availability of orchid seeds does not seem to limit their distribution. These results can provide useful guidelines for conservation of the studied species.
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Affiliation(s)
- Lucie Hemrová
- Institute of Botany, Czech Academy of Sciences, 252 43, Průhonice, Czech Republic.
| | - Milan Kotilínek
- Faculty of Science, University of South Bohemia, 370 05, České Budějovice, Czech Republic
| | - Marie Konečná
- Faculty of Science, University of South Bohemia, 370 05, České Budějovice, Czech Republic
| | - Radim Paulič
- Městský úřad Strakonice, Odbor životního prostředí, Velké náměstí 2, 386 01, Strakonice, Czech Republic
| | - Jana Jersáková
- Faculty of Science, University of South Bohemia, 370 05, České Budějovice, Czech Republic
| | - Tamara Těšitelová
- Faculty of Science, University of South Bohemia, 370 05, České Budějovice, Czech Republic
| | - Jana Knappová
- Institute of Botany, Czech Academy of Sciences, 252 43, Průhonice, Czech Republic.,Department of Botany, Faculty of Science, Charles University, 128 01, Prague, Czech Republic
| | - Zuzana Münzbergová
- Institute of Botany, Czech Academy of Sciences, 252 43, Průhonice, Czech Republic.,Department of Botany, Faculty of Science, Charles University, 128 01, Prague, Czech Republic
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Izuddin M, Yam TW, Webb EL. Germination niches and seed persistence of tropical epiphytic orchids in an urban landscape. JOURNAL OF PLANT RESEARCH 2019; 132:383-394. [PMID: 31006042 DOI: 10.1007/s10265-019-01110-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2018] [Accepted: 04/05/2019] [Indexed: 06/09/2023]
Abstract
Urbanisation has contributed to significant biodiversity loss, yet, urban areas can facilitate biodiversity conservation. For instance, there is evidence of urban trees supporting natural establishments of orchids, the most species-rich plant family on Earth. However, the germination niches-which include both suitable biophysical conditions and orchid mycorrhizal fungus/fungi (OMF)-are not sufficiently known for most species, especially tropical epiphytic orchids. The fate of their dispersed seeds is poorly understood as well. We conducted fungal baiting and seed sowing experiments, next-generation sequencing, generalised linear models, and seed viability tests to detect and identify potential OMF, investigate biophysical factors that influenced OMF availability and orchid germination, and assess seed longevity. Ceratobasidiaceae- and Serendipitaceae-associated OMF were successfully detected in three of four orchid species. In general, orchid species and humus presence had significant effects on OMF availability. Orchid species and temperature were predictive of germination. Post-experiment viability tests revealed that one orchid species, Grammatophyllum speciosum Blume, may produce long-lived seeds. The results suggest that urban trees can support OMF and orchid germination, but both processes are limited by biophysical factors. This study also indicates the possibility of seed persistence among epiphytic species. As orchid germination niches are complex and tend to be unique to individual species, we do not encourage generalisations. In contrast, species-specific information can help formulate useful recommendations towards conservation.
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Affiliation(s)
- Muhammad Izuddin
- Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore, 117543, Singapore.
| | - Tim Wing Yam
- Singapore Botanic Gardens, 1 Cluny Road, Singapore, 259569, Singapore
| | - Edward L Webb
- Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore, 117543, Singapore
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Xing X, Jacquemyn H, Gai X, Gao Y, Liu Q, Zhao Z, Guo S. The impact of life form on the architecture of orchid mycorrhizal networks in tropical forest. OIKOS 2019. [DOI: 10.1111/oik.06363] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Xiaoke Xing
- Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Inst. of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College CN‐100193 Beijing PR China
| | - Hans Jacquemyn
- KU Leuven, Dept of Biology, Plant Conservation and Population Biology Leuven Belgium
| | - Xuege Gai
- Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Inst. of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College CN‐100193 Beijing PR China
| | - Yue Gao
- Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Inst. of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College CN‐100193 Beijing PR China
| | - Qiang Liu
- Yunnan Forestry Technological College, Kunming Yunnan PR China
| | - Zeyu Zhao
- Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Inst. of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College CN‐100193 Beijing PR China
| | - Shunxing Guo
- Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Inst. of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College CN‐100193 Beijing PR China
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Chen Y, Gao Y, Song L, Zhao Z, Guo S, Xing X. Mycorrhizal fungal community composition in seven orchid species inhabiting Song Mountain, Beijing, China. SCIENCE CHINA-LIFE SCIENCES 2019; 62:838-847. [PMID: 30810964 DOI: 10.1007/s11427-018-9471-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Accepted: 11/26/2018] [Indexed: 12/21/2022]
Abstract
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.
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Affiliation(s)
- Yanhong Chen
- 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, Beijing, 100193, China
| | - Yue Gao
- 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, Beijing, 100193, China
| | - Linli Song
- 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, Beijing, 100193, China
| | - Zeyu Zhao
- 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, Beijing, 100193, China
| | - Shunxing Guo
- 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, Beijing, 100193, China
| | - 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, Beijing, 100193, China.
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Kariman K, Barker SJ, Tibbett M. Structural plasticity in root-fungal symbioses: diverse interactions lead to improved plant fitness. PeerJ 2018; 6:e6030. [PMID: 30533314 PMCID: PMC6284451 DOI: 10.7717/peerj.6030] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Accepted: 10/30/2018] [Indexed: 01/08/2023] Open
Abstract
Root-fungal symbioses such as mycorrhizas and endophytes are key components of terrestrial ecosystems. Diverse in trophy habits (obligate, facultative or hemi-biotrophs) and symbiotic relations (from mutualism to parasitism), these associations also show great variability in their root colonization and nutritional strategies. Specialized interface structures such as arbuscules and Hartig nets are formed by certain associations while others are restricted to non-specialized intercellular or intracellular hyphae in roots. In either case, there are documented examples of active nutrient exchange, reinforcing the fact that specialized structures used to define specific mycorrhizal associations are not essential for reciprocal exchange of nutrients and plant growth promotion. In feremycorrhiza (with Austroboletus occidentalis and eucalypts), the fungal partner markedly enhances plant growth and nutrient acquisition without colonizing roots, emphasizing that a conventional focus on structural form of associations may have resulted in important functional components of rhizospheres being overlooked. In support of this viewpoint, mycobiome studies using the state-of-the-art DNA sequencing technologies have unearthed much more complexity in root-fungal relationships than those discovered using the traditional morphology-based approaches. In this review, we explore the existing literature and most recent findings surrounding structure, functioning, and ecology of root-fungal symbiosis, which highlight the fact that plant fitness can be altered by taxonomically/ecologically diverse fungal symbionts regardless of root colonization and interface specialization. Furthermore, transition from saprotrophy to biotrophy seems to be a common event that occurs in diverse fungal lineages (consisting of root endophytes, soil saprotrophs, wood decayers etc.), and which may be accompanied by development of specialized interface structures and/or mycorrhiza-like effects on plant growth and nutrition.
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Affiliation(s)
- Khalil Kariman
- School of Agriculture and Environment, The University of Western Australia, Crawley, Western Australia, Australia
| | - Susan Jane Barker
- School of Agriculture and Environment, The University of Western Australia, Crawley, Western Australia, Australia
| | - Mark Tibbett
- Centre for Agri-Environmental Research & Soil Research Centre, School of Agriculture Policy and Development, University of Reading, Berkshire, United Kingdom
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Cevallos S, Declerck S, Suárez JP. In situ Orchid Seedling-Trap Experiment Shows Few Keystone and Many Randomly Associated Mycorrhizal Fungal Species During Early Plant Colonization. FRONTIERS IN PLANT SCIENCE 2018; 9:1664. [PMID: 30505314 PMCID: PMC6250785 DOI: 10.3389/fpls.2018.01664] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Accepted: 10/26/2018] [Indexed: 05/20/2023]
Abstract
Orchids are known for their vast diversity and dependency on mycorrhizal fungi. Under in situ conditions, the biotic and abiotic factors determining the composition and distribution of orchid mycorrhizal fungi (OMF) communities remain largely unexplored. Therefore in situ experiments are needed to better understand the interactions between orchids and fungi. A seedling-trap experiment was conducted in the Reserva Biológica San Francisco, a well-known biodiversity hotspot located in the Andes of southern Ecuador. The objective was to investigate the effect of orchid species, site, elevation or temporal variation on the assembly and structure of OMF associated with Cyrtochilum retusum and Epidendrum macrum. The OMF community composition was determined using the Illumina MiSeq sequencing of the internal transcribed spacer 2 (ITS2) region. The results exhibited 83 OMF operational taxonomic units belonging to Tulasnellaceae, Ceratobasidiaceae, Serendipitaceae and Atractiellales. It was observed that the composition of the OMF communities was different among orchid species and temporal variation but was not different among sites. The results further support that orchids have a core of keystone OMF that are ubiquitously distributed and stable across temporal change, whereas the majority of these fungi are randomly associated with the plants.
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Affiliation(s)
- Stefania Cevallos
- Laboratory of Mycology, Earth and Life Institute, Université catholique de Louvain, Louvain-la-Neuve, Belgium
- Departamento de Ciencias Biológicas, Universidad Técnica Particular de Loja, Loja, Ecuador
| | - Stéphane Declerck
- Laboratory of Mycology, Earth and Life Institute, Université catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Juan Pablo Suárez
- Departamento de Ciencias Biológicas, Universidad Técnica Particular de Loja, Loja, Ecuador
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McCormick MK, Whigham DF, Canchani-Viruet A. Mycorrhizal fungi affect orchid distribution and population dynamics. THE NEW PHYTOLOGIST 2018; 219:1207-1215. [PMID: 29790578 DOI: 10.1111/nph.15223] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Accepted: 04/17/2018] [Indexed: 05/03/2023]
Abstract
Symbioses are ubiquitous in nature and influence individual plants and populations. Orchids have life history stages that depend fully or partially on fungi for carbon and other essential resources. As a result, orchid populations depend on the distribution of orchid mycorrhizal fungi (OMFs). We focused on evidence that local-scale distribution and population dynamics of orchids can be limited by the patchy distribution and abundance of OMFs, after an update of an earlier review confirmed that orchids are rarely limited by OMF distribution at geographic scales. Recent evidence points to a relationship between OMF abundance and orchid density and dormancy, which results in apparent density differences. Orchids were more abundant, less likely to enter dormancy, and more likely to re-emerge when OMF were abundant. We highlight the need for additional studies on OMF quantity, more emphasis on tropical species, and development and application of next-generation sequencing techniques to quantify OMF abundance in substrates and determine their function in association with orchids. Research is also needed to distinguish between OMFs and endophytic fungi and to determine the function of nonmycorrhizal endophytes in orchid roots. These studies will be especially important if we are to link orchids and OMFs in efforts to inform conservation.
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Affiliation(s)
- Melissa K McCormick
- Smithsonian Environmental Research Center, 647 Contees Wharf Rd, Edgewater, MD, 21037, USA
| | - Dennis F Whigham
- Smithsonian Environmental Research Center, 647 Contees Wharf Rd, Edgewater, MD, 21037, USA
| | - Armando Canchani-Viruet
- Smithsonian Environmental Research Center, 647 Contees Wharf Rd, Edgewater, MD, 21037, USA
- Universidad Metropolitana, Escuela de Ciencias y Tecnología, 1399 Avenida Ana G. Mendez, San Juan, 00926, Puerto Rico
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Egidi E, May TW, Franks AE. Seeking the needle in the haystack: Undetectability of mycorrhizal fungi outside of the plant rhizosphere associated with an endangered Australian orchid. FUNGAL ECOL 2018. [DOI: 10.1016/j.funeco.2018.01.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Pecoraro L, Caruso T, Cai L, Gupta VK, Liu ZJ. Fungal networks and orchid distribution: new insights from above- and below-ground analyses of fungal communities. IMA Fungus 2018; 9:1-11. [PMID: 30018868 PMCID: PMC6048571 DOI: 10.5598/imafungus.2018.09.01.01] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Accepted: 01/27/2018] [Indexed: 01/27/2023] Open
Abstract
Orchids are critically dependent on fungi for seedling establishment and growth, so the distribution and diversity of orchids might depend on the associated fungal communities. We characterised the communities associated with eight orchid species in three Mediterranean protected areas, using a combination of above-ground analyses of sporophores and below-ground molecular analyses of orchid root samples. In three years of sporophore collection in 25 plots around flowering orchid plants, 268 macrofungal species belonging to 84 genera were observed. Statistical analyses indicated a correlation between macrofungal diversity and orchid community variation, regardless of the effect of environmental and spatial factors characterizing the investigated orchid sites. Fungal ITS-DNA PCR amplification, cloning, and sequencing revealed Rhizoctonia-like fungi belonging to Ceratobasidiaceae (26 %), Tulasnellaceae (22.5 %), and Sebacinaceae (3.5 %), as well as other basidiomycetes and ascomycetes, in the roots of 99 orchid plants. Mycorrhizal specificity was low but co-occurring orchid species showed preferences for different partners. The diverse macrofungal communities found in the sites may contribute to orchid community variation without colonizing the orchid roots. Molecular analyses revealed a segregation of associated fungi, which may contribute to Mediterranean orchid coexistence in nature.
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Affiliation(s)
- Lorenzo Pecoraro
- Shenzhen Key Laboratory for Orchid Conservation and Utilization, The National Orchid Conservation Center of China and The Orchid Conservation and Research Center of Shenzhen, 518114 Shenzhen, China
- Center for Biotechnology & BioMedicine and Division of Life & Health Sciences, Graduate School at Shenzhen, Tsinghua University, 518055 Shenzhen, China
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, 100101 Beijing, China
| | - Tancredi Caruso
- School of Biological Sciences, Queen's University of Belfast, BT9 7BL Belfast, Northern Ireland
| | - Lei Cai
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, 100101 Beijing, China
| | - Vijai Kumar Gupta
- Department of Chemistry and Biotechnology, ERA Chair of Green Chemistry, School of Science, Tallinn University of Technology, 12618 Tallinn, Estonia
| | - Zhong-Jian Liu
- Shenzhen Key Laboratory for Orchid Conservation and Utilization, The National Orchid Conservation Center of China and The Orchid Conservation and Research Center of Shenzhen, 518114 Shenzhen, China
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Lee BH, Kwon WJ, Kim JY, Park JS, Eom AH. Differences among Endophytic Fungal Communities Isolated from the Roots of Cephalanthera longibracteata Collected from Different Sites in Korea. MYCOBIOLOGY 2017; 45:312-317. [PMID: 29371798 PMCID: PMC5780362 DOI: 10.5941/myco.2017.45.4.312] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Revised: 10/25/2017] [Accepted: 11/06/2017] [Indexed: 05/09/2023]
Abstract
Orchidaceous plants have symbiotic relationships with endophytic fungi, including mycorrhizal fungi, which play important roles in the seed germination and growth of the host plants. In this study, endophytic fungal communities isolated from the roots of Cephalanthera longibracteata collected from three different sites in Korea were analyzed, and it was determined whether fungal communities were preferentially correlated with the sites. The fungal isolates were identified by sequence analysis of the internal transcribed spacer regions of rDNA. In total, 30 species of endophytic fungi, including two species of mycorrhizal fungi belonging to the genus Tulasnella, were identified. Leptodontidium orchidicola showed the highest frequency and was isolated from all root samples. Species diversity and richness were not significantly different among sites. However, the community structure of the endophytic fungi significantly differed among sites, suggesting that the site characteristics affected the community composition of the endophytic fungi colonizing the roots of C. longibracteata. Our findings will aid in developing methods involving the use of symbiotic fungi for orchid conservation and restoration in native habitats.
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Affiliation(s)
- Bong-Hyung Lee
- Department of Biology Education, Korea National University of Education, Cheongju 28173, Korea
- Chungbuk Science High School, Cheongju 28189, Korea
| | - Woo-Jin Kwon
- Chungbuk Science High School, Cheongju 28189, Korea
| | | | - Jin-Seo Park
- Chungbuk Science High School, Cheongju 28189, Korea
| | - Ahn-Heum Eom
- Department of Biology Education, Korea National University of Education, Cheongju 28173, Korea
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Zettler LW, Rajaovelona L, Yokoya K, Kendon JP, Stice AL, Wood AE, Sarasan V. Techniques for the collection, transportation, and isolation of orchid endophytes from afar: a case study from Madagascar. BOTANICAL STUDIES 2017; 58:54. [PMID: 29185075 PMCID: PMC5705530 DOI: 10.1186/s40529-017-0209-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Accepted: 11/21/2017] [Indexed: 05/07/2023]
Abstract
BACKGROUND Tropical orchids need more study with respect to their mycorrhizal associations. For researchers in distant countries who aspire to study these orchids augmenting their conservation, the great distances involved, coupled with limited funds, pose formidable challenges. These challenges are sometimes exacerbated by political unrest, delays in securing permits, unexpected hardships, and the risk that the biological samples collected (e.g., roots harboring mycorrhizal fungi) will not survive long-distance transport. RESULTS We describe a protocol for the collection and transport of root samples from Madagascar orchids to labs in the United Kingdom (Kew) and the United States (Illinois) where Rhizoctonia-like fungi were subsequently isolated. Three separate trips were made spanning 4 years (2012-2015), with emphasis on the collection of roots from epiphytic, lithophytic, and terrestrial orchids inhabiting the Itremo Massif of the Central Highlands. Collectively, the trips to Madagascar resulted in the isolation of all major groups of Rhizoctonia-like fungi (Ceratobasidium, Tulasnella, Sebacina) from all three orchid growth forms (terrestrials, epiphytes and lithophytes). Sampling of terrestrial and epiphytes during the rainy season (January) yielded best results. CONCLUSIONS Our study demonstrates that peloton-forming fungi in root samples can retain viability up to 3 weeks after collection.
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Affiliation(s)
- Lawrence W. Zettler
- Department of Biology, Illinois College, 1101 West College Ave., Jacksonville, IL 62650 USA
| | - Landy Rajaovelona
- Kew Madagascar Conservation Centre, Lot #J131B, Ambodivaonjo-Ivandry, 101, Antananarivo, Madagascar
| | | | | | - Andrew L. Stice
- Department of Biology, Illinois College, 1101 West College Ave., Jacksonville, IL 62650 USA
| | - Amanda E. Wood
- Department of Biology, Illinois College, 1101 West College Ave., Jacksonville, IL 62650 USA
- Environmental Studies Program, University of Pennsylvania, Philadelphia, PA 19104 USA
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Genetic diversity of endangered orchid Phaius australis across a fragmented Australian landscape. CONSERV GENET 2017. [DOI: 10.1007/s10592-017-1022-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Levy Karin E, Ashkenazy H, Wicke S, Pupko T, Mayrose I. TraitRateProp: a web server for the detection of trait-dependent evolutionary rate shifts in sequence sites. Nucleic Acids Res 2017; 45:W260-W264. [PMID: 28453644 PMCID: PMC5570260 DOI: 10.1093/nar/gkx288] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 04/02/2017] [Accepted: 04/26/2017] [Indexed: 11/23/2022] Open
Abstract
Understanding species adaptation at the molecular level has been a central goal of evolutionary biology and genomics research. This important task becomes increasingly relevant with the constant rise in both genotypic and phenotypic data availabilities. The TraitRateProp web server offers a unique perspective into this task by allowing the detection of associations between sequence evolution rate and whole-organism phenotypes. By analyzing sequences and phenotypes of extant species in the context of their phylogeny, it identifies sequence sites in a gene/protein whose evolutionary rate is associated with shifts in the phenotype. To this end, it considers alternative histories of whole-organism phenotypic changes, which result in the extant phenotypic states. Its joint likelihood framework that combines models of sequence and phenotype evolution allows testing whether an association between these processes exists. In addition to predicting sequence sites most likely to be associated with the phenotypic trait, the server can optionally integrate structural 3D information. This integration allows a visual detection of trait-associated sequence sites that are juxtapose in 3D space, thereby suggesting a common functional role. We used TraitRateProp to study the shifts in sequence evolution rate of the RPS8 protein upon transitions into heterotrophy in Orchidaceae. TraitRateProp is available at http://traitrate.tau.ac.il/prop.
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Affiliation(s)
- Eli Levy Karin
- Department of Cell Research and Immunology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
- Department Molecular Biology and Ecology of Plants, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
| | - Haim Ashkenazy
- Department of Cell Research and Immunology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
- Department Molecular Biology and Ecology of Plants, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
| | - Susann Wicke
- Institute for Evolution and Biodiversity, University of Muenster, Muenster, Germany
| | - Tal Pupko
- Department of Cell Research and Immunology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
| | - Itay Mayrose
- Department Molecular Biology and Ecology of Plants, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
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50
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Oja J, Vahtra J, Bahram M, Kohout P, Kull T, Rannap R, Kõljalg U, Tedersoo L. Local-scale spatial structure and community composition of orchid mycorrhizal fungi in semi-natural grasslands. MYCORRHIZA 2017; 27:355-367. [PMID: 28039600 DOI: 10.1007/s00572-016-0755-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2016] [Accepted: 11/30/2016] [Indexed: 05/20/2023]
Abstract
Orchid mycorrhizal (OrM) fungi play a crucial role in the ontogeny of orchids, yet little is known about how the structure of OrM fungal communities varies with space and environmental factors. Previous studies suggest that within orchid patches, the distance to adult orchids may affect the abundance of OrM fungi. Many orchid species grow in species-rich temperate semi-natural grasslands, the persistence of which depends on moderate physical disturbances, such as grazing and mowing. The aim of this study was to test whether the diversity, structure and composition of OrM fungal community are influenced by the orchid patches and management intensity in semi-natural grasslands. We detected putative OrM fungi from 0 to 32 m away from the patches of host orchid species (Orchis militaris and Platanthera chlorantha) in 21 semi-natural calcareous grasslands using pyrosequencing. In addition, we assessed different ecological conditions in semi-natural grasslands but primarily focused on the effect of grazing intensity on OrM fungal communities in soil. We found that investigated orchid species were mostly associated with Ceratobasidiaceae and Tulasnellaceae and, to a lesser extent, with Sebacinales. Of all the examined factors, the intensity of grazing explained the largest proportion of variation in OrM fungal as well as total fungal community composition in soil. Spatial analyses showed limited evidence for spatial clustering of OrM fungi and their dependence on host orchids. Our results indicate that habitat management can shape OrM fungal communities, and the spatial distribution of these fungi appears to be weakly structured outside the orchid patches.
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Affiliation(s)
- Jane Oja
- Institute of Ecology and Earth Sciences, University of Tartu, 14A Ravila, 50411, Tartu, Estonia.
| | - Johanna Vahtra
- Institute of Ecology and Earth Sciences, University of Tartu, 14A Ravila, 50411, Tartu, Estonia
| | - Mohammad Bahram
- Institute of Ecology and Earth Sciences, University of Tartu, 14A Ravila, 50411, Tartu, Estonia
- Department of Organismal Biology, Evolutionary Biology Centre, Uppsala University, SE 75236, Uppsala, Sweden
| | - Petr Kohout
- Institute of Ecology and Earth Sciences, University of Tartu, 14A Ravila, 50411, Tartu, Estonia
- Institute of Botany, Academy of Sciences of the Czech Republic, 252 43, Průhonice, Czech Republic
- Department of Experimental Plant Biology, Faculty of Science, Charles University, CZ-128 01, Prague 2, Czech Republic
| | - Tiiu Kull
- Institute of Agricultural and Environmental Sciences Estonian, University of Life Sciences, 5 Kreutzwaldi, 51014, Tartu, Estonia
| | - Riinu Rannap
- Institute of Ecology and Earth Sciences, University of Tartu, 46 Vanemuise, 51014, Tartu, Estonia
| | - Urmas Kõljalg
- Institute of Ecology and Earth Sciences, University of Tartu, 14A Ravila, 50411, Tartu, Estonia
| | - Leho Tedersoo
- Institute of Ecology and Earth Sciences, University of Tartu, 14A Ravila, 50411, Tartu, Estonia
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