Spatio‐temporal Analysis of the Effects of Hurricane Ivan on Two Contrasting Epiphytic Orchid Species in Guanahacabibes,Cuba

Hurricanes represent the dominant type of disturbance in many tropical coastal forests. Here, we focus on mortality of epiphytic orchids caused by hurricane Ivan in the Guanahacabibes National Park (Cuba) and subsequent population recovery. We analyzed different aspects of hurricane damage on two contrasting epiphytic orchids, Broughtonia cubensis and Dendrophylax lindenii, as observed in three plots of coastal vegetation and in three plots of semi‐deciduous forest, respectively. First, we quantified the damage to host trees and orchids and explored if hurricane damage depended on height, size, or identity of the host tree. Second, we used mark connection and mark correlation functions to conduct a detailed analysis of small‐scale spatial patterns in hurricane damage for host trees and orchids. Finally, we analyzed the degree of recovery after Ivan during the 6 yr following the storm. Damage of B. cubensis host trees was independent of height and size, but Ivan severely affected larger and higher host trees of D. lindenii. Spatial analysis revealed non‐random structure in damage that differed between species. Broughtonia cubensis exhibited small‐scale spatial correlation in the proportion of damaged orchids, whereas D. lindenii did not. Dendrophylax lindenii showed ‘patchy’ damage patterns, correlated with height, but B. cubensis did not. The relative growth rate of B. cubensis for the 5–17 mo following Ivan was only moderately reduced and fully recovered in subsequent years, whereas that of D. lindenii was severely reduced the first year and did not fully recover thereafter. We hypothesize that differences in the host, vegetation type, and the traits of the two orchids contribute to the different responses to the hurricane.     

西双版纳片段化石灰岩森林附生兰科植物多样性研究

西双版纳石灰岩地区拥有丰富的兰科植物资源,但近年来随着橡胶树的大面积种植,使得该地区很多石灰岩森林呈片段化。为了解片段化石灰岩森林中附生兰科植物多样性状况以及片段化对附生兰科植物的影响,该研究选取了生境片段化的青岩寨和曼纳览,以及连续生境的绿石林和巴卡新寨等4个样地的29个样方进行多样性调查和对比研究。结果表明:4个石灰岩森林样共记录到附生兰科植物34属76种1 528株(丛)。通过对坡向、坡度、海拔、地形、郁闭度和森林类型等6个环境因子与附生兰科植物丰富度进行CCA分析,发现石灰岩地区附生兰科植物的分布主要受海拔和森林类型2个因素的影响,在海拔较高的青岩寨和巴卡新寨附生兰科植物物种丰富度高于低海拔的绿石林和曼纳览,而片段化对附生兰科植物的物种多样性和多度均无显著影响,这可能与片段化的历史较短有关。虽然目前来看生境片段化对石灰岩地区的附生兰科植物多样性无显著影响,但生境脆弱的石灰岩森林植被的保护对于兰科植物多样性保护则更具重要性。     

Host tree utilization by epiphytic orchids in different land-use intensities in Kathmandu Valley, Nepal

We studied the influence of site conditions on epiphytic orchids under a subtropical climate in the Kathmandu Valley, Nepal. We analysed 96 systematically distributed grid points situated in Kathmandu Valley across a land-use intensity gradient (national park to urbanised city area). Geographical Information System (GIS) and remote sensing were used for classification of land-use types. We identified 23 species of epiphytic orchids, within 13 genera, from 42 different host tree species. Host preference is obvious for some orchid species (e.g., Dendrobium nobile), with certain tree species (e.g., Schima wallichii, Ficus religiosa) hosting more orchid species than others. The orchid Rhynchostylis retusa was the most common species found on many different host tree species across the land-use intensity gradient. Host species and host bark characteristics (e.g., rugosity, pH and exposure to wind) played a vital role for orchid distribution, with lower abundance in areas of higher impact. Under strong human impact (urban city area), F. religiosa was the dominant host tree, with large individual trees (mean diameter in breast height, dbh?=?1.3?m) providing the habitat for considerable populations of R. retusa individuals. In general, epiphytic orchids were found on larger host trees in urban areas than in areas of lower human impact. We found that some hosts are more likely to harbour orchid species, especially native host species. Older larger trees with rougher bark, low pH, exposed to wind and reduced human impact provided better habitats for orchids. We suggest these characteristics should be considered in urban planning to reduce human impact on the associated orchid epiphytic community.     

Distribution,habitat disturbance and pollination of the endangered orchid Broughtonia cubensis (Epidendrae: Laeliinae)

The geographical distribution, population structure and pollination ecology are key aspects in the conservation and management of rare orchids. Here, we address these aspects and the main threats affecting the endangered Cuban orchid Broughtonia cubensis. This rewardless orchid is self‐compatible, but pollinator dependent. However, seed production can be negatively affected by insect‐mediated selfing. Three species of small bee (genera Ceratina and Lasioglossum) act as pollinators. As in the case of other nectarless orchids, we detected two species of plant producing large amounts of nectar in the area, the floral morphology of which closely resembles that of B. cubensis. The simultaneous flowering of these species could positively affect the reproductive success of B. cubensis. Nonetheless, the fitness of this orchid in natural conditions is low, possibly related to strong pollen limitation. To the problems arising from reduced fitness is added the fact that its historical distribution range has been greatly reduced in recent years. Throughout this study, we have detected dramatic reductions in the population sizes, in some cases as a result of human plundering, but also as a consequence of hurricanes. Based on the results of this study, we propose some guidelines to manage and conserve this orchid. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013, 172 , 345–357.     

Generalism in the interaction of Tulasnellaceae mycobionts with orchids characterizes a biodiversity hotspot in the tropical Andes of Southern Ecuador

Biotic interactions play an important role in the assembly and stability of communities. All orchids depend on mycobionts for early establishment, but whether individual orchid species depend on a specific or broad spectrum of mycobionts is still a matter of debate. Tulasnellaceae (Basidiomycota) is the richest and most widespread mycobiont worldwide. We assessed Tulasnellaceae richness in epiphytic and terrestrial orchids in different habitats, and evaluated the degree of generalism in orchid-Tulasnellaceae interactions and the robustness of this mutualistic system to the extinction of mycobiont partners. We sampled 114 orchid individuals including all common and rare species in 56 plots of 1 m² in 3 habitats: pristine forest, regenerating forest and a landslide site in a tropical montane rainforest in Southern Ecuador. We found 52 orchid and 29 Tulasnellaceae species. The composition of Tulasnellaceae OTUs was moderately to highly similar across habitats and between orchid growth forms. A significantly nested network architecture indicated the existence of a core of generalist Tulasnellaceae OTUs interacting with both rare and common orchids. Terrestrial and epiphytic orchids showed significant differences in robustness to the extinction of their Tulasnellaceae mycobionts. Thus, generalist mycobionts may be relevant for the preservation of hyperdiverse orchid communities in the tropics.     

Effects of fire regimen on two species of epiphytic orchids in tropical savannas of the Northern Territory

The effect of four fire regimens (early dry season annual, late dry season annual, early dry season biennial, unburnt) on the numbers of epiphytic orchids in a savanna community in Kakadu National Park was investigated. These fire regimens had been maintained on I ha plots for 16 years. Two species of epiphytic orchid were present — Cymbidium canaliculatum and Dendrobium affine. The numbers of Cymbidium plants were insufficient to enable statistical analysis, but plants were present in the unburnt, early annual and early biennial fire treatments. Dendrobium occurred in substantial numbers irrespective of fire treatment, but the extent of colonization of all available host trees was greater in the unburnt than the burnt treatments. The lower numbers of Dendrobium plants in burnt treatments was due to a lower proportion of potential host trees being colonized and a lower number of orchids on each colonized tree. The proportion of small trees colonized was markedly lower in burnt treatments. Frequent fires late in the dry season may prevent recruitment of the main host species. Eucalyptus tectifica. The survival of orchids despite frequent fires depended on the availability of relatively protected sites for colonization and the ability of the orchids to withstand some fire damage.     

The intimacy between sexual traits and Grime’s CSR strategies for orchids coexisting in semi-natural calcareous grassland at the Olive Lawn

The diversity of orchid species in semi-natural calcareous grassland is thought to depend on floral variability. However, differences in primary life-history strategy, or the overall suite of functional traits, could also affect coexistence. Both primary strategy (affecting day-to-day survival) and reproductive traits (representing periodic events) have been hypothesized to contribute to a general mechanism regulating the local persistence and relative abundance of species. We recorded species identity at 8,000 points at the centimetre scale along sixteen 5-m long transects at the Olive Lawn, a xeric sand calcareous grassland near Lecco, Italy. Transects allowed the relative abundance and spatial aggregation of Grime’s competitor, stress-tolerator, ruderal (CSR) strategies to be quantified. Orchid flowering and fruiting phenology was recorded alongside the phenology of graminoid growth. Seven orchid species were present and exhibited a spectrum of strategies spanning two extremes, (1) small early-flowering ruderals (R/CR-selected), and (2) larger-leaved competitors (C/CR) flowering later as dominant graminoids attained maximum height. These orchids, and other subordinate species in the community, exhibited random spatial distributions amongst dominant graminoids that exhibited a high degree of spatial aggregation and similar, but non-identical, stress-tolerator (S) strategies. The reproductive phenology of meadow orchids is an intimate component of their CSR strategies, and appears to promote coexistence by allowing segregation between temporal niches and the exploitation of opportunities between clumps of dominant species. Only for closely related species with identical CSR strategies, such as Ophrys benacensis and Ophrys sphegodes, could specific floral differences alone explain coexistence.     

Diversity,distribution and host-species associations of epiphytic orchids in Nepal

Associations between epiphytes and their hosts are among the main factors affecting the biodiversity and distribution of epiphytes. While several previous studies explored the association between epiphyte diversity and host characteristics, very little is known about the generality of such associations at larger spatial scales. We aim to explore the associations between diversity and distribution of epiphytic orchids and host characteristics in different localities in Nepal. Epiphytic orchids and their hosts were recorded along the transects in total of 23,539 host individuals. To describe the diversity of orchids in the different localities, a rarefaction function was used. Univariate and multivariate analyses were carried out to explore the associations with locality, host characteristics, and their interactions with locality. In total, we recorded 141 species of orchids growing on 192 host species. The five localities significantly differed in orchid diversity and abundance. The number of orchid individuals per host species significantly increased with increasing number of host individuals. Species richness, abundances, occupancy of orchid species on host species and composition of orchids varied across the localities. Species richness and abundance was significantly higher on hosts in the higher strata and differed between families of host species. Abundance was higher on evergreen hosts. Composition of orchid communities are also associated with host characteristics, such as habit (shrub/tree/climber), bark texture, nature (deciduous/evergreen) and the plant families of host species. This study revealed a high diversity of epiphytic orchids in the localities studied and strong associations between the orchids and their hosts. Future studies looking at the relationships between epiphyte communities and host characteristics need to identify relationships at a wider scale in order to determine whether they are really general rather than site-specific.     

The impact of life form on the architecture of orchid mycorrhizal networks in tropical forest

Understanding the processes that determine the architecture of interaction networks represents a major challenge in ecology and evolutionary biology. One of the most important interactions involving plants is the interaction between plants and mycorrhizal fungi. While there is a mounting body of research that has studied the architecture of plant–fungus interaction networks, less is known about the potential factors that drive network architecture. In this study, we described the architecture of the network of interactions between mycorrhizal fungi and 44 orchid species that represented different life forms and co‐occurred in tropical forest and assessed the relative importance of ecological, evolutionary and co‐evolutionary mechanisms determining network architecture. We found 87 different fungal operational taxonomic units (OTUs), most of which were members of the Tulasnellaceae. Most orchid species associated with multiple fungi simultaneously, indicating that extreme host selectivity was rare. However, an increasing specificity towards Tulasnellaceae fungal associates from terrestrial to epiphytic and lithophytic orchids was observed. The network of interactions showed an association pattern that was significantly modular (M = 0.7389, M_random = 0.6998) and nested (NODF = 5.53, p < 0.05). Terrestrial orchids had almost no links to modules containing epiphytic or lithophytic orchids, while modules containing epiphytic orchids also contained lithophytic orchids. Within each life form several modules were observed, suggesting that the processes that organize orchid–fungus interactions are independent of life form. The overall phylogenetic signal for both partners in the interaction network was very weak. Overall, these results indicate that tropical orchids associate with a wide number of mycorrhizal fungi and that ecological rather than phylogenetic constraints determine network architecture.     

Fruit set, nectar reward, and rarity in the Orchidaceae

A review of comparative levels of reproductive success among nectariferous and nectarless orchids worldwide was compiled from a comprehensive survey of fruit set from 117 orchid species in the literature and from our own field studies. It confirms the hypothesis that nectariferous orchids are more successful in setting fruit than are nectarless species. Overall fruit set figures for nectarless and nectariferous orchids were 19.5 and 49.3% for North America, 27.7 and 63.1% for Europe, 41.4 and 74.4% for the temperate southern hemisphere, and 11.5 and 24.9% for the tropics, demonstrating that the dichotomy is consistent across all geographical areas. On average, the provision of nectar doubles the probability of fruit set in both temperate and tropical areas, but tropical orchids are remarkable in that all (whether nectarless or nectariferous, or terrestrial or epiphytic) display low fruit productivity (<50%). Fruiting failure in the tropics may be balanced by higher productivity per capsule, since tropical orchid fruits contain on average 150 times more seeds than temperate ones. Hybridization occurs more frequently among nectarless orchids in Britain and Europe than among nectariferous ones, and there is a significant positive association between orchid rarity and lack of nectar reward in the British Isles. Sexual reproduction in the Orchidaceae is predominantly pollinator dependent, but this can sometimes be successfully circumvented by asexual seed production (agamospermy) or, more frequently, by automatic self-pollination (autogamy). The proportion of highly successful nectarless orchids from all geographic areas is very low and comparable with that of orchids offering rewards other than nectar (～14% of species in each case) emphasizing that high reproductive success is only associated with nectar reward (53% of species). It is suggested that the evolution of nectar production within the family has been the most frequent means of escaping the reproductive limitations of low pollinator visitation frequencies.     

Many broadly-shared mycobionts characterize mycorrhizal interactions of two coexisting epiphytic orchids in a high elevation tropical forest

Interspecific interactions play an important role in community assembly. A basic ecological question is whether interactions are specialized (one to one) or generalized (many to many). Specialization of interactions should ideally be assessed across several populations because species could be specialists at a particular site but generalists when several sites are considered. Mycorrhizal interactions are fundamental for orchid life and distribution, but their level of specialization is still under debate. To understand the extent to which epiphytic orchids are specialists in their mycorrhizal interactions, we studied the richness and phylogenetic structure of mycobionts across different sites, and the similarity in the mycobiont composition between coexisting orchid species. We sequenced the nrDNA ITS2 region and explored the mycobiont communities associated with two epiphytic orchids, Epidendrum marsupiale and Cyrtochilum pardinum, at two elevations within two sites in Ecuador. We found 108 OTUs belonging to Serendipitaceae (66), Ceratobasidiaceae (22), Atractiellales (11) and Tulasnellaceae (9). Orchids at the highest elevations hosted the highest OTU richness. The two orchid species shared a high percentage of mycobionts between all sites. No phylogenetic structure within orchid mycorrhizal communities was found at any sites or elevations. Our results indicate that the studied orchids are generalists and share a broad group of mycobionts (16 OTUs) with no apparent niche segregation within or between sites.     

A nocturnal Provespa wasp species as the probable pollinator of epiphytic orchid Coelogyne fimbriata

Many vespid wasps visit flowers to forage nectar. These hymenopterans sometimes contribute to flower pollination. However, none of the nocturnal wasp species is a known pollinator. We collected individuals of light‐attracted Provespa nocturna workers in a montane rainforest on Peninsular Malaysia: some wasps collected bore orchid pollinia on their thoraxes. Among 114 trapped individuals, four bore pollinaria and nine bore only viscidia, suggesting that pollinia had been successfully transported. Molecular barcoding of the pollinia (based on their ITS sequences) assigned the orchid to a species in Coelogyne fimbriata complex. These findings and our other analyses suggest that this nocturnal wasp contributes to pollination of an epiphytic nectarless orchid that probably releases olfactory attractants. This discovery sheds light on the importance of mutualistic relationships between the nocturnal social wasps and epiphytic orchids in Southeast Asian tropical rainforest canopies.     

Impact of floral traits on the reproductive success of epiphytic and terrestrial tropical orchids

We investigated the relationship between habit, population size, floral traits and natural fruit set levels of 23 tropical orchid species of south-east Bangladesh. We showed that epiphytic orchids had lower fruit set levels than terrestrial species and that habit explained much of the variation in floral traits among the orchids. We compared our results with data from 76 other species occurring in the study area and hypothesize that a suite of floral and population characteristics present in tropical orchids combine in epiphytes to reduce their reproductive success. Characteristics which, in addition to their habit, are associated with low reproductive success are small population size, small inflorescences, non-sectile pollinia and self-incompatibility. Several of these characteristics were phylogenetically conserved and we predict that epiphytes might therefore generally have lower fruit set levels than recorded in terrestrial species. Nectar rewards are uncommon in tropical orchids and nectarless species have displays of larger flowers, which may represent an adaptation to increase pollinator attraction, although other rewards such as oils, waxes and pseudo pollen may replace nectar. We suggest that, like many temperate orchids, a high proportion of tropical orchids may lack floral rewards and be pollinated by deceit.     

Untangling above‐ and belowground mycorrhizal fungal networks in tropical orchids

Orchids typically depend on fungi for establishment from seeds, forming mycorrhizal associations with basidiomycete fungal partners in the polyphyletic group rhizoctonia from early stages of germination, sometimes with very high specificity. This has raised important questions about the roles of plant and fungal phylogenetics, and their habitat preferences, in controlling which fungi associate with which plants. In this issue of Molecular Ecology, Martos et al. (2012) report the largest network analysis to date for orchids and their mycorrhizal fungi, sampling a total of over 450 plants from nearly half the 150 tropical orchid species on Reunion Island, encompassing its main terrestrial and epiphytic orchid genera. The authors found a total of 95 operational taxonomic units of mycorrhizal fungi and investigated the architecture and nestedness of their bipartite networks with 73 orchid species. The most striking finding was a major ecological barrier between above‐ and belowground mycorrhizal fungal networks, despite both epiphytic and terrestrial orchids often associating with closely related taxa across all three major lineages of rhizoctonia fungi. The fungal partnerships of the epiphytes and terrestrial species involved a diversity of fungal taxa in a modular network architecture, with only about one in ten mycorrhizal fungi partnering orchids in both groups. In contrast, plant and fungal phylogenetics had weak or no effects on the network. This highlights the power of recently developed ecological network analyses to give new insights into controls on plant–fungal symbioses and raises exciting new hypotheses about the differences in properties and functioning of mycorrhiza in epiphytic and terrestrial orchids.     

Endophytic fungi assemblages from 10 <Emphasis Type="Italic">Dendrobium</Emphasis> medicinal plants (Orchidaceae)

Dendrobium is the largest genus of tropical epiphytic orchid, some of which are traditional Chinese medicinal plants. The therapeutic components varied significantly among species. Endophytic microbes (fungi) hidden in medicinal plants may play an important effect on the overall quality of herb. Investigation of fungal composition in host plants is the first step toward elucidating the relationship endophyte-therapeutic content of herbal medicine. In this study, 401 culturable fungal endophytes were isolated and identified from 10 species of medicinal Dendrobium based on morphological and molecular techniques. The results showed that endophytic fungi from Dendrobium plants exhibited high biodiversity (37 genera, about 80 species). Acremonium, Alternaria, Ampelomyces, Bionectria, Cladosporium, Colletotrichum, Fusarium, Verticillium and Xylaria were the dominant fungal endophytes. Tropical epiphytic orchids appear to vary in degree of host specificity in their endophytic fungi.     

Mycorrhizal Fungi Promote Growth and Nitrogen Utilization by Dendrobium nobile (Orchidaceae)

Mycorrhizal associations play a key role in the life cycle and evolutionary history of orchids. Although most orchid species are tropical and epiphytic, their mycorrhizae are poorly understood compared with those of temperate, terrestrial orchids. To investigate the influences of such fungi on photosynthetic, epiphytic orchids, we inoculated seedlings of Dendrobium nobile with Epulorhiza sp. (S1) or Tulasnella sp. (S3). These fungi had been identified based on their morphological and molecular characters. Both S1 and S3 formed symbiotic associations with our seedlings, promoting their growth and development to various degrees. Results from signature experiments with the 15N stable isotope suggested that the utilization of organic nitrogen by orchid seedlings was significantly improved by S1, but not by S3. Dendrobine contents were significantly higher in all inoculated seedlings. Our findings demonstrate that these mycorrhizal fungi enhance plant growth, their utilization of organic nitrogen, and the accumulation of secondary metabolites in this epiphytic orchid species.     

Host trait preferences and distribution of vascular epiphytes in a warm-temperate forest

To illustrate the ecological factors and process leading to the observed diversity patterns of vascular epiphytes, we examined the effect and importance of host tree traits on epiphyte richness and spatial aggregation of epiphytes. The study was conducted in warm-temperate forest in Japan. The recorded host traits were diameter, height, species, habitat topography, and growth rate, and we analyzed the effects and importance of these traits on three species groups: total epiphytic species, epiphytic orchid species, and epiphytic pteridophyte species. Diameter and species of host trees had the greatest influence on epiphytes and their magnitudes were roughly similar in all species groups. Growth rate and topography were less important than host size and species. Growth rate had a negative effect on all three groups, and topography was important for pteridophytes. Epiphyte richness did not exhibit clear spatial aggregation. Our results suggest that size, stability, and quality of the host are equally important in determining epiphyte colonization.     

菌根真菌促进金钗石斛的生长及氮利用

菌根在兰科的生命周期和进化史上起着关键作用。兰科中大多数是附生兰,但它们的菌根研究相对缺乏。为了探讨菌根对附生兰的影响,本研究用金钗石斛（Dendrobium nobile）与通过形态学特征和分子生物学鉴定的分属于瘤菌根菌属（Epulorhiza）的s1和胶膜菌属（Tulasnella）的S3真菌共培养。共培养结果表明,S1和S3与金钗石斛形成了共生关系,且不同程度地促进了其生长。15N稳定同位素标记实验证实,S1菌株显著促进了金钗石斛对有机氮的利用,而S3菌株没有显著的促进作用。同时．S1和S3真菌均能提高金钗石斛中石斛碱的含量。研究结果表明,菌根真菌能促进附生兰幼苗的生长、有机氮的利用和次生代射产物的积累。     

Influence of mycorrhizal fungi on seed germination and growth in terrestrial and epiphytic orchids

Epiphytes constitute over 70% of orchid diversity, but little is known about the functioning of their mycorrhizal associations. Terrestrial orchid seeds germinate symbiotically in soil and leaf litter, whereas epiphytic orchids may be exposed to relatively high light levels from an early stage of development and often produce green seeds. This suggests that seedlings of the two groups of orchids may differ in their responses to light and requirements for mycorrhiza-supplied carbon. The interactive effects of light, exogenous carbon and mycorrhizal status on germination and growth were investigated in vitro using axenic agar microcosms for one tropical epiphyte and three geophytic orchid species. The geophytic species strongly depended on their mycorrhiza for growth and this could not be substituted by exogenous sucrose, whereas the epiphytic species achieved 95% of the mycorrhizal seedling volume when supplied with exogenous sucrose in the dark. Mycorrhiza status strongly interacted with light exposure, enabling germination. Light inhibited or severely reduced growth, especially for the terrestrial orchids in the absence of mycorrhiza. For the first time, this study showed the parallel ecological importance of mycorrhizal fungi in overcoming light inhibition of seed germination and growth in both terrestrial and epiphytic orchids.     

Studies of Mycorrhizal Fungi of Chinese Orchids and Their Role in Orchid Conservation in China—A Review

China has over 1,200 species of native orchids in nearly 173 genera. About one fourth of native species are of horticultural merit. Some species are of Chinese medicinal value. In fact, the demand on orchid species with high Chinese medicinal values such as Gastrodia elata, Dendrobium offcinale, along with demands on species of cultural importance, such as those in the genus of Cymbidium, is a major factor causing wild populations to diminish and in some cases, drive wild populations to the brink of extinction. These market demands have also driven studies on the role of mycorrhizal fungi in orchid seed germination, seedling and adult growth, and reproduction. Most of these mycorrhizal studies of Chinese orchids, however, are published in Chinese, some in medical journals, and thus overlooked by the mainstream orchid mycorrhizal publications. Yet some of these studies contained interesting discoveries on the nature of the mycorrhizal relationships between orchids and fungi. We present a review of some of these neglected publications. The most important discovery comes from the mycorrhizal studies on G. elata, in which the researchers concluded that those fungi species required to stimulate seed germination are different from those that facilitate the growth of G. elata beyond seedling stages. In addition, presence of the mycorrhizal fungi associated with vegetative growth of post-seedling G. elata hindered the germination of seeds. These phenomena were unreported prior to these studies. Furthermore, orchid mycorrhizal studies in China differ from the mainstream orchid studies in that many epiphytic species (in the genus of Dendrobium, as medicinal herbs) were investigated as well as terrestrial orchids (mostly in the genus Cymbidium, as traditional horticultural species). The different responses between epiphytic and terrestrial orchid seeds to fungi derived from roots suggest that epiphytic orchids may have a more general mycorrhizal relationship with fungi than do terrestrial orchid species during the seed germination stage. To date, orchid mycorrhizal research in China has had a strongly commercial purpose. We suggest that this continuing research on orchid mycorrhizal relationships are a solid foundation for further research that includes more rare and endangered taxa, and more in-situ studies to assist conservation and restoration of the endangered orchids. Knowledge on the identities and roles of mycorrhizal fungi of orchids holds one of the keys to successful restoration and sustainable use of Chinese orchids.