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Summary The effect of 3-indoleacetic acid (IAA), 6-furfurylaminopurine (kinetin), and gibberellic acid (GA3) on germination of the orchid Comparettia falcata was evaluated in a factorial experiment (4×4×4) with Murashige and Skoog (1962) basal medium. It was established that seeds
of this orchid could be maintained under aseptic conditions as long as the necessary nutrients and appropriate concentrations
of growth regulators were provided. Of the three growth regulators used, IAA significantly decreased seed germination of Comparettia falcata. There was a synergistic effect in the kinetin:GA3 combination that produced a positive response in both percentage seed germination and development of seedlings. This study
describes a single medium-based protocol able to achieve more than 160000 seedlings within 21 wk, starting from a single capsule,
sufficient for both large-scale propagation and in vitro conservation of this threatened orchid. 相似文献
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Symbiotic seed germination of Habenaria macroceratitis (Orchidaceae), a rare Florida terrestrial orchid 总被引:1,自引:0,他引:1
The rapid loss of native orchid habitat throughout ecologically important areas (e.g., Florida) has prompted researchers to develop appropriate plans for the propagation and reintroduction of many native orchid species. Ideally, symbiotic orchid seed germination methods are utilized in the production of orchid seedlings to be used in plant reintroduction programs. In the current study we (1) describe an efficient symbiotic seed germination protocol to germinate seeds of the rare sub-tropical terrestrial orchid Habenaria macroceratitis; (2) discuss the in vitro fungal specificity demonstrated by this species; and (3) describe the effects of three photoperiods (0/24 h, 16/8 h, 24/0 h L/D) on in vitro symbiotic seed germination of H. macroceratitis. Six fungal mycobionts were isolated from both vegetative and flowering plants of H. macroceratitis from two geographically distinct sites. Symbiotic seed germination percent was highest (65.7%) and protocorm development was most advanced (Stage 2) when seeds were cultured with fungal mycobiont Hmac-310. Seeds of H. macroceratitis demonstrated a degree of specificity toward fungal mycobionts isolated from plants originating from the same site where seed was collected. Continual darkness (0/24 h L/D) inhibited initial seed germination (Stage 1; 17.1%), but stimulated subsequent protocorm development (Stage 2; 53.5%). These findings will aid in developing an efficient symbiotic seed germination protocol for the conservation of this rare Florida terrestrial orchid, and may prove useful in the conservation of other sub-tropical terrestrial orchid species. 相似文献
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The identity of mycorrhizal fungi associated with the achlorophyllous orchid Epipogium roseum was investigated by DNA analysis. The fungi were isolated from each coiled hypha (peloton), and the ITS region of nuclear rDNA was sequenced. Phylogenetic analysis based on the neighbor-joining method showed that all the isolates clustered with fungi belonging to Psathyrella or Coprinus in Coprinaceae. Those fungi are known as saprobes, using dead organic materials for a nutritive source. Large colonies of this orchid were frequently found around tree stumps or fallen logs. In such colonies, these decaying wood materials would be used as a large and persistent carbon source for the growth of this orchid. This is the first report of Coprinaceae as an orchid mycorrhizal fungi. 相似文献
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Compared with mycorrhizal relationships, the relationships between mycoheterotrophic plants and insects have rarely been studied. Here we report a previously unknown tripartite interaction among an endangered mycoheterotrophic orchid, an orchid‐feeding fly, and a parasitoid wasp. The flowers and stems of Eulophia zollingeri were heavily attacked by Japanagromyza tokunagai (Sasakawa) (Diptera: Agromyzidae), and the parasitoid wasp Gronotoma guamensis (Yoshimoto) (Hymenoptera: Figitidae) was reared from these J. tokunagai individuals. Considering the high infestation rate of J. tokunagai, G. guamensis could be important in suppressing the J. tokunagai population, and positively affect the reproductive success of E. zollingeri. 相似文献
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Arild R. Arifin Ryan D. Phillips Celeste C. Linde 《Journal of evolutionary biology》2023,36(1):221-237
The study of congruency between phylogenies of interacting species can provide a powerful approach for understanding the evolutionary history of symbiotic associations. Orchid mycorrhizal fungi can survive independently of orchids making cospeciation unlikely, leading us to predict that any congruence would arise from host-switches to closely related fungal species. The Australasian orchid subtribe Drakaeinae is an iconic group of sexually deceptive orchids that consists of approximately 66 species. In this study, we investigated the evolutionary relationships between representatives of all six Drakaeinae orchid genera (39 species) and their mycorrhizal fungi. We used an exome capture dataset to generate the first well-resolved phylogeny of the Drakaeinae genera. A total of 10 closely related Tulasnella Operational Taxonomic Units (OTUs) and previously described species were associated with the Drakaeinae orchids. Three of them were shared among orchid genera, with each genus associating with 1–6 Tulasnella lineages. Cophylogenetic analyses show Drakaeinae orchids and their Tulasnella associates exhibit significant congruence (p < 0.001) in the topology of their phylogenetic trees. An event-based method also revealed significant congruence in Drakaeinae–Tulasnella relationships, with duplications (35), losses (25), and failure to diverge (9) the most frequent events, with minimal evidence for cospeciation (1) and host-switches (2). The high number of duplications suggests that the orchids speciate independently from the fungi, and the fungal species association of the ancestral orchid species is typically maintained in the daughter species. For the Drakaeinae–Tulasnella interaction, a pattern of phylogenetic niche conservatism rather than coevolution likely explains the observed phylogenetic congruency in orchid and fungal phylogenies. Given that many orchid genera are characterized by sharing of fungal species between closely related orchid species, we predict that these findings may apply to a wide range of orchid lineages. 相似文献
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A total of 40 specimens of the genus Schizothorax (Cyprinidae: Schizothoracinae), including 10 matured males, 19 matured females and 11 juveniles, were captured from the Kirong Tsangpo River in China, which is located in the southern slope of the Central Himalayas. These specimens are identified as Schizothorax richardsonii (Grey, 1832) based on morphological characters and molecular analyses using mitochondrial Cyt b gene sequences. The Kirong population of S. richardsonii is relatively isolated from other populations in the Himalayas and has low genetic diversity. This is the first record of the genus Schizothorax fish in rivers of the Central Himalayas in China. As S. richardsonii is a vulnerable species on the IUCN Red List, a protection plan should be conducted to reduce the impact of anthropogenic disturbance by monitoring the natural population dynamics and assessing the ecological determinants of its distribution. 相似文献
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NIGEL D. SWARTS ELIZABETH A. SINCLAIR ANTHONY FRANCIS KINGSLEY W. DIXON 《Molecular ecology》2010,19(15):3226-3242
Terrestrial orchid germination, growth and development are closely linked to the establishment and maintenance of a relationship with a mycorrhizal fungus. Mycorrhizal dependency and specificity varies considerably between orchid taxa but the degree to which this underpins rarity in orchids is unknown. In the context of examining orchid rarity, large scale in vitro and in situ germination trials complemented by DNA sequencing were used to investigate ecological specialization in the mycorrhizal interaction of the rare terrestrial orchid Caladenia huegelii. Common and widespread sympatric orchid congeners were used for comparative purposes. Germination trials revealed an absolute requirement for mycorrhisation with compatibility barriers to germination limiting C. huegelii to a highly specific and range limited, efficacious mycorrhizal fungus. DNA sequencing confirmed fidelity between orchid and fungus across the distribution range of C. huegelii and at key life history stages within its life cycle. It was also revealed that common congeners could swap or share fungal partners including the fungus associated with the rare orchid but not vice versa. Data from this study provides evidence for orchid rarity as a cause and consequence of high mycorrhizal specialization. This interaction must be taken into account in efforts to mitigate the significant extinction risk for this species from anthropogenically induced habitat change and illustrates the importance of understanding fungal specificity in orchid ecology and conservation. 相似文献
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《Journal of Plant Interactions》2013,8(1):825-831
Changes in the activity of lysine decarboxylase (LDC), tyrosine decarboxylase (TyDC), and ornithine decarboxylase (ODC) within orchid (Phalaenopsis × hybridum ‘Innocence’) leaves, infested by two mealybug species: Pseudococcus longispinus (Targ. Tozz.) and Pseudococcus maritimus (Ehrh.) were quantified. The pattern of changes was dependent on the insect species and duration of infestation. P. longispinus feeding increased LDC and TyDC activity after one week during the total period of observations. This species inhibited ODC activity after one week but increased later. P. maritimus decreased LDC activity in orchid leaves at all studied terms. TyDC action also went up during the first week of the infestation and was reduced after two weeks, while ODC was decreased after one day and induced later. The mechanism for the participation of analysed amino acid decarboxylases in local and/or systemic steps of orchid responses to mealybug infestation is discussed. 相似文献
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The plant family Orchidaceae has a great economic value (ornamental and medical uses, beside the aromatic features). Traditionally,
identification of orchid species has relied heavily on morphological features. These features, however, are either not variable
enough between species or too plastic to be used for identification at the species level. DNA-based markers could be the alternative
strategy towards an accurate and robust identification of those species. Since the chloroplast DNA has a lower level of evolution
compared to the nuclear genome, an attempt was made in this study to investigate polymorphism in the chloroplast DNA among
orchid species distributed in North-West region of Syria using Cleaved Amplified Polymorphic Sequence (CAPS) technique for
developing markers for the diagnosis of targeted species. CAPS analysis was carried out on 34 orchid samples that represent
all species observed in the region. Universal primers were used to amplify targeted chloroplast regions. Generated PCR products
were digested with various restriction enzymes. CAPS results revealed high polymorphism among species examined. This polymorphism
was suffiecient for the diagnosis of all of those species apart from five species (Ophrys fuciflora (one sample), Oph. bornmuelleri, Ophrys sp., scolopax and Oph. argolica). Availability of such species-specific markers would ensure more authentic identification of orchid species compared to
morphological characters and can be regarded as a valuable tool to guide in conservation programs of orchid species in Syria.
CAPS data generated were converted to an identification key for orchid species studied. 相似文献
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Growth and enzymatic activities of extraradical mycelia (ERM) of native mycorrhizal symbionts associated with three orchid
species, Dactylorhiza fuchsii, D. majalis and Platanthera bifolia, were studied. ERM extracted from the mycorrhizosphere of these species showed features typical for fungi that form orchid
mycorrhiza. In the first pot experiment, three different treatments were applied on tubers of D. fuchsii transplanted from a natural site: control (no specific treatment), reinoculated (surface-sterilized tubers reinoculated with
mycorrhizal fungi-colonised roots), and benomyl (nonsterilized tubers treated with fungicide). However, no significant differences
in ERM growth and intensity of root mycorrhizal colonisation at harvest were observed among these treatments. ERM associated
with reinoculated D. fuchsii plants showed significantly higher alkaline phosphatase (ALP) enzymatic activity at week 36 than at week 24, but no differences
were observed for NADH diaphorase activity. Benomyl application significantly reduced ALP activity in comparison with reinoculated
plants at week 36. In the second experiment, plants of all three species were either untreated (control), or repeatedly treated
with benomyl. Similarly to the results of the first experiment, benomyl application did not reduce the ERM growth of mycorrhizal
symbionts associated with D. majalis and D. fuchsii. The low ERM growth associated with benomyl-treated P. bifolia was probably caused by poor root system development in this treatment. Significantly higher mycorrhizal colonisation was
found for D. fuchsii compared to P. bifolia in control treatments at the end of cultivation. The ERM of native symbionts of the three orchid species studied seemed to
have a different growth pattern over time and responded differently to fungicide application. 相似文献
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Jochen Martens Dieter Thomas Tietze Siegfried Eck Michael Veith 《Journal of Ornithology》2004,145(3):206-222
Pallass Warbler (Phylloscopus proregulus) of the Eastern Palaearctic (Siberia, China, Himalayas) resolves into a complex of four closely related but distinct allospecies forming a superspecies, P. [proregulus]. Assignment of species rank is based on cytochrome-b gene sequences and on vocalisations (territorial song and calls). Morphological divergence is poor, as is typical in Phylloscopus. It applies to size (nominate Siberian proregulus as opposed to the Sino-Himalayan taxa), and slight coloration differences among the latter taxa do not correspond to the cyt-b topology and are considered to be adaptive. Vocal differences relate to syntax (verse song vs endless song), frequency (broad vs narrow bandwidth, allocation of elements within the frequency band), form of elements (ascending vs descending parts, combination of these), and repertoire size. Strong premating isolating mechanisms are assigned to vocalisations. Contrary to current taxonomy, we propose the following constituent taxa of the Phylloscopus [proregulus] complex: Phylloscopus proregulus s.str. (Siberia, disjunct from the following taxa), P. kansuensis (China: Gansu, Qinghai), P. forresti (W/SW China, part of E Himalayas?), P. chloronotus with two subspecies: P. c. simlaensis (W Himalayas), and P. c. chloronotus (C and E Himalayas). Contact zones and possible hybridisation between the Sino-Himalayan taxa remain undetermined. A closely related isospecies is Phylloscopus yunnanensis (syn. P. sichuanensis), which is locally sympatric with and extremely similar morphologically to P. forresti and P. kansuensis. Cyt-b distance values range from 3.1% to 4.6% within the P. proregulus complex and from 7.5% to 8.4% between the latter and P. yunnanensis. This corresponds to differentiation times of 4.1 to 5.5 Myears (P. proregulus complex vs P. yunnanensis) and 1.7 to 3.2 Myears (within the P. proregulus complex).Electronic Supplementary Material Supplementary material is available in the online version of this article at
Communicated by A. Helbig*Results of the Himalaya Expeditions of J. Martens, No. 247. – For No. 246 see: Ann Zool Warszawa, 2004.This revised version was published online in July 2004 with corrections to a heading and species names. 相似文献
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Although the terrestrial and temperate orchids–fungal biology have been largely explored, knowledge of tropical epiphytic
orchids–fungus relationships, especially on the ecological roles imparted by non-mycorrhizal fungal endophytes, is less known.
Exploitation of the endophytic fungal mycobiota residing in epiphytic orchid plants may be of great importance to further
elucidate the fungal ecology in this special habitat as well as developing new approaches for orchid conversations. The composition
of fungal endophytes associated with leaves, stems and roots of an epiphytic orchid (Dendrobium nobile), a famous Chinese traditional medicinal plant, was investigated. Microscopic imaging, culture-dependant method and molecular
phylogeny were used to estimate their entity and diversity. Totally, there were 172 isolates, at least 14 fungal genera and
33 different morphospecies recovered from 288 samples. Ascomycetes, coelomycetes and hyphomycetes were three major fungal
groups. There were higher overall colonization and isolation rates of endophytic fungi from leaves than from other tissues.
Guignardia mangiferae was the dominant fungal species within leaves; while the endophytic Xylariaceae were frequently observed in all plant tissues; Colletotrichum, Phomopsis and Fusarium were also frequently observed. Phylogenetic analysis based on ITS gene revealed the high diversity of Xylariacea fungi and relatively diverse of non-Xylariacea fungi. Some potentially promising beneficial fungi such as Clonostachys rosea and Trichoderma chlorosporum were found in roots. This is the first report concerning above-ground and below-ground endophytic fungi community of an epiphytic
medicinal orchid, suggesting the ubiquitous distribution of non-mycorrhizal fungal endophytes in orchid plants together with
heterogeneity and tissue specificity of the endophyte assemblage. Possible physiological functions played by these fungal
endophytes and their potential applications are also discussed briefly.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
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HANS JACQUEMYN OLIVIER HONNAY BRUNO P. A. CAMMUE REIN BRYS BART LIEVENS 《Molecular ecology》2010,19(18):4086-4095
Most orchid species rely on mycorrhizae to complete their life cycle. Despite a growing body of literature identifying orchid mycorrhizal associations, the nature and specificity of the association between orchid species and mycorrhizal fungi remains largely an open question. Nonetheless, better insights into these obligate plant–fungus associations are indispensable for understanding the biology and conservation of orchid populations. To investigate orchid mycorrhizal associations in five species of the genus Orchis (O. anthropophora, O. mascula, O. militaris, O. purpurea, and O. simia), we developed internal transcribed spacer‐based DNA arrays from extensive clone library sequence data sets, enabling rapid and simultaneous detection of a wide range of basidiomycetous mycorrhizal fungi. A low degree of specificity was observed, with two orchid species associating with nine different fungal partners. Phylogenetic analysis revealed that the majority of Orchis mycorrhizal fungi are members of the Tulasnellaceae, but in some plants, members of the Thelephoraceae, Cortinariaceae and Ceratobasidiaceae were also found. In all species except one (O. mascula), individual plants associated with more than one fungus simultaneously, and in some cases, associations with ≥3 mycorrhizal fungi at the same time were identified. Nestedness analysis showed that orchid mycorrhizal associations were significantly nested, suggesting asymmetric specialization and a dense core of interactions created by symmetric interactions between generalist species. Our results add support to the growing literature that multiple associations may be common among orchids. Low specificity or preference for a widespread fungal symbiont may partly explain the wide distribution of the investigated species. 相似文献
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Microbiota of the Orchid Rhizoplane 总被引:1,自引:0,他引:1
E. A. Tsavkelova T. A. Cherdyntseva E. S. Lobakova G. L. Kolomeitseva A. I. Netrusov 《Microbiology》2001,70(4):492-497
Six bacterial strains isolated from the underground roots of the terrestrial orchid Calanthe vestitavar. rubro-oculatawere found to belong to the genera Arthrobacter, Bacillus, Mycobacterium, and Pseudomonas.Strains isolated from the aerial roots of the epiphytic orchid Dendrobium moschatumwere classified into the genera Bacillus, Curtobacterium, Flavobacterium, Nocardia, Pseudomonas, Rhodococcus, and Xanthomonas.The rhizoplane of the terrestrial orchid was also populated by cyanobacteria of the genera Nostocand Oscillatoria, whereas that of the epiphytic orchid was populated by one genus, Nostoc.In orchids occupying different econiches, the spectra of the bacterial genera revealed differed. The microbial complex of the terrestrial orchid rhizoplane differed from that of the surrounding soil. 相似文献
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Transgene silencing in Phalaenopsis expressing the coat protein of Cymbidium Mosaic Virus is a manifestation of RNA-mediated resistance 总被引:2,自引:0,他引:2
Liao Li-Jen Pan I-Chun Chan Yuan-Li Hsu Yau-Heiu Chen Wen-Huei Chan Ming-Tsair 《Molecular breeding : new strategies in plant improvement》2004,13(3):229-242