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Sample records for orchid dendrobium thyrsiflorum

  1. Somatic Embryogenesis in Two Orchid Genera (Cymbidium, Dendrobium).

    PubMed

    da Silva, Jaime A Teixeira; Winarto, Budi

    2016-01-01

    The protocorm-like body (PLB) is the de facto somatic embryo in orchids. Here we describe detailed protocols for two orchid genera (hybrid Cymbidium Twilight Moon 'Day Light' and Dendrobium 'Jayakarta', D. 'Gradita 31', and D. 'Zahra FR 62') for generating PLBs. These protocols will most likely have to be tweaked for different cultivars as the response of orchids in vitro tends to be dependent on genotype. In addition to primary somatic embryogenesis, secondary (or repetitive) somatic embryogenesis is also described for both genera. The use of thin cell layers as a sensitive tissue assay is outlined for hybrid Cymbidium while the protocol outlined is suitable for bioreactor culture of D. 'Zahra FR 62'. PMID:26619873

  2. Transformation of Dendrobium orchid using particle bombardment of protocorms.

    PubMed

    Kuehnle, A R; Sugii, N

    1992-08-01

    Transformed dendrobium orchids (Dendrobium x Jaquelyn Thomas hybrids) were recovered from protocorms bombarded by particles coated with the plasmid pGA482GG/cpPRV4, which contains the plant expressible Nos-NPT II and papaya ringspot virus (PRV) coat protein (CP) genes. Approximately 280 protocorms from four crosses were bombarded and potentially transformed tissues were identified by growth and green color on half-strength Murashige and Skoog medium supplemented with 2% sucrose and 50-100 mg 1(-1) kanamycin sulfate. Kanamycin concentrations that prevented growth of nontransformed tissues could not be used for long-term selection because such levels suppressed the regeneration of potentially transformed tissues. PCR and restriction analysis 21 months after treatment found 13 of 13 plants from two crosses, which appeared kanamycin-tolerant, to contain the Nos-NPT II gene, while only one of these plants carried the vector-linked PRV CP-gene. These results support use of particle bombardment for transformation of this important ornamental monocot. PMID:24201595

  3. Multiple shoot induction from axillary bud cultures of the medicinal orchid, Dendrobium longicornu

    PubMed Central

    Dohling, Stadwelson; Kumaria, Suman; Tandon, Pramod

    2012-01-01

    Background and aims Dendrobium longicornu, commonly known as the ‘Long-horned Dendrobium’, is an endangered and medicinally important epiphytic orchid. Over-exploitation and habitat destruction seriously threaten this orchid in Northeast India. Our objective was to develop an efficient protocol for the mass propagation of D. longicornu using axillary bud segments. Methodology and principal results Axillary buds cultured in Murashige and Skoog semi-solid medium supplemented with α-naphthalene acetic acid (NAA), 2,4-dichlorophenoxy acetic acid (2,4-D) and 6-benzylaminopurine (BAP) readily developed into plantlets. These formed either directly from shoot buds or from intermediary protocorm-like bodies (PLBs). The maximum explant response (86.6 %) was obtained in medium supplemented with NAA at 30 µM, while the maximum number of shoots (4.42) and maximum bud-forming capacity (3.51) were observed in medium containing 15 µM BAP and 5 µM NAA in combination. Protocorm-like bodies were obtained when the medium contained 2,4-D. The maximum number of explants forming PLBs (41.48 %) was obtained in medium containing 15 µM BAP and 15 µM 2,4-D. Well-developed plantlets obtained after 20–25 weeks of culture were acclimatized and eventually transferred to the greenhouse. Over 60 % of these survived to form plants ∼3–4 cm tall after 90 days in glasshouse conditions using a substrate of crushed brick and charcoal, shredded bark and moss. Conclusions The method described can readily be used for the rapid and large-scale regeneration of D. longicornu. Its commercial adoption would reduce the collection of this medicinally important and increasingly rare orchid from the wild. PMID:23136638

  4. A transcriptome-wide, organ-specific regulatory map of Dendrobium officinale, an important traditional Chinese orchid herb.

    PubMed

    Meng, Yijun; Yu, Dongliang; Xue, Jie; Lu, Jiangjie; Feng, Shangguo; Shen, Chenjia; Wang, Huizhong

    2016-01-01

    Dendrobium officinale is an important traditional Chinese herb. Here, we did a transcriptome-wide, organ-specific study on this valuable plant by combining RNA, small RNA (sRNA) and degradome sequencing. RNA sequencing of four organs (flower, root, leaf and stem) of Dendrobium officinale enabled us to obtain 536,558 assembled transcripts, from which 2,645, 256, 42 and 54 were identified to be highly expressed in the four organs respectively. Based on sRNA sequencing, 2,038, 2, 21 and 24 sRNAs were identified to be specifically accumulated in the four organs respectively. A total of 1,047 mature microRNA (miRNA) candidates were detected. Based on secondary structure predictions and sequencing, tens of potential miRNA precursors were identified from the assembled transcripts. Interestingly, phase-distributed sRNAs with degradome-based processing evidences were discovered on the long-stem structures of two precursors. Target identification was performed for the 1,047 miRNA candidates, resulting in the discovery of 1,257 miRNA--target pairs. Finally, some biological meaningful subnetworks involving hormone signaling, development, secondary metabolism and Argonaute 1-related regulation were established. All of the sequencing data sets are available at NCBI Sequence Read Archive (http://www.ncbi.nlm.nih.gov/sra/). Summarily, our study provides a valuable resource for the in-depth molecular and functional studies on this important Chinese orchid herb. PMID:26732614

  5. A transcriptome-wide, organ-specific regulatory map of Dendrobium officinale, an important traditional Chinese orchid herb

    PubMed Central

    Meng, Yijun; Yu, Dongliang; Xue, Jie; Lu, Jiangjie; Feng, Shangguo; Shen, Chenjia; Wang, Huizhong

    2016-01-01

    Dendrobium officinale is an important traditional Chinese herb. Here, we did a transcriptome-wide, organ-specific study on this valuable plant by combining RNA, small RNA (sRNA) and degradome sequencing. RNA sequencing of four organs (flower, root, leaf and stem) of Dendrobium officinale enabled us to obtain 536,558 assembled transcripts, from which 2,645, 256, 42 and 54 were identified to be highly expressed in the four organs respectively. Based on sRNA sequencing, 2,038, 2, 21 and 24 sRNAs were identified to be specifically accumulated in the four organs respectively. A total of 1,047 mature microRNA (miRNA) candidates were detected. Based on secondary structure predictions and sequencing, tens of potential miRNA precursors were identified from the assembled transcripts. Interestingly, phase-distributed sRNAs with degradome-based processing evidences were discovered on the long-stem structures of two precursors. Target identification was performed for the 1,047 miRNA candidates, resulting in the discovery of 1,257 miRNA--target pairs. Finally, some biological meaningful subnetworks involving hormone signaling, development, secondary metabolism and Argonaute 1-related regulation were established. All of the sequencing data sets are available at NCBI Sequence Read Archive (http://www.ncbi.nlm.nih.gov/sra/). Summarily, our study provides a valuable resource for the in-depth molecular and functional studies on this important Chinese orchid herb. PMID:26732614

  6. In vitro propagation of Dendrobium macrostachyum Lindl.--a threatened orchid.

    PubMed

    Pyati, A N; Murthy, H N; Hahn, E J; Paek, K Y

    2002-05-01

    In vitro propagation of Dendrobium macrostachyum, a threatened and endemic species was achieved through nodal explants. The nodal explants were cultured on Murashige and Skoog (MS) basal medium and MS medium supplemented with N6-benzyladenine (BA-2.22, 4.44 and 8.88 microM), Kinetin (KN-2.32, 4.65, and 9.29 microM) and Coconut water (CW, 5, 10 and 15%) individually or in combination with 2.69 microM alpha-naphthalene acetic acid (NAA). Axillary shoots were induced directly from nodal explants in medium containing BA, KN or CW. Optimal shoot induction (6 shoots/explant) was attained from nodal explants cultured on medium supplemented with 15% CW. Well developed shoots rooted at an average 5 roots per shoot in half strength MS medium devoid of any growth regulators. PMID:12622215

  7. Genetic stability and phytochemical analysis of the in vitro regenerated plants of Dendrobium nobile Lindl., an endangered medicinal orchid.

    PubMed

    Bhattacharyya, Paromik; Kumaria, Suman; Diengdoh, Reemavareen; Tandon, Pramod

    2014-12-01

    An efficient genetically stable regeneration protocol with increased phytochemical production has been established for Dendrobium nobile, a highly prized orchid for its economic and medicinal importance. Protocorm like bodies (PLBs) were induced from the pseudostem segments using thidiazuron (TDZ; 1.5 mg/l), by-passing the conventional auxin-cytokinin complement approach for plant regeneration. Although, PLB induction was observed at higher concentrations of TDZ, plantlet regeneration from those PLBs was affected adversely. The best rooting (5.41 roots/shoot) was achieved in MS medium with 1.5 mg/l TDZ and 0.25% activated charcoal. Plantlets were successfully transferred to a greenhouse with a survival rate of 84.3%, exhibiting normal development. Genetic stability of the regenerated plants was investigated using randomly amplified polymorphic DNA (RAPD) and start codon targeted (SCoT) polymorphism markers which detected 97% of genetic fidelity among the regenerants. The PIC values of RAPD and SCoT primers were recorded to be 0.92 and 0.76 and their Rp values ranged between 3.66 and 10, and 4 and 12 respectively. The amplification products of the regenerated plants showed similar banding patterns to that of the mother plant thus demonstrating the homogeneity of the micropropagated plants. A comparative phytochemical analysis among the mother and the micropropagated plants showed a higher yield of secondary metabolites. The regeneration protocol developed in this study provides a basis for ex-situ germplasm conservation and also harnesses the various secondary metabolite compounds of medicinal importance present in D. nobile. PMID:25606433

  8. Genetic stability and phytochemical analysis of the in vitro regenerated plants of Dendrobium nobile Lindl., an endangered medicinal orchid

    PubMed Central

    Bhattacharyya, Paromik; Kumaria, Suman; Diengdoh, Reemavareen; Tandon, Pramod

    2014-01-01

    An efficient genetically stable regeneration protocol with increased phytochemical production has been established for Dendrobium nobile, a highly prized orchid for its economic and medicinal importance. Protocorm like bodies (PLBs) were induced from the pseudostem segments using thidiazuron (TDZ; 1.5 mg/l), by-passing the conventional auxin–cytokinin complement approach for plant regeneration. Although, PLB induction was observed at higher concentrations of TDZ, plantlet regeneration from those PLBs was affected adversely. The best rooting (5.41 roots/shoot) was achieved in MS medium with 1.5 mg/l TDZ and 0.25% activated charcoal. Plantlets were successfully transferred to a greenhouse with a survival rate of 84.3%, exhibiting normal development. Genetic stability of the regenerated plants was investigated using randomly amplified polymorphic DNA (RAPD) and start codon targeted (SCoT) polymorphism markers which detected 97% of genetic fidelity among the regenerants. The PIC values of RAPD and SCoT primers were recorded to be 0.92 and 0.76 and their Rp values ranged between 3.66 and 10, and 4 and 12 respectively. The amplification products of the regenerated plants showed similar banding patterns to that of the mother plant thus demonstrating the homogeneity of the micropropagated plants. A comparative phytochemical analysis among the mother and the micropropagated plants showed a higher yield of secondary metabolites. The regeneration protocol developed in this study provides a basis for ex-situ germplasm conservation and also harnesses the various secondary metabolite compounds of medicinal importance present in D. nobile. PMID:25606433

  9. Overexpression of an Orchid (Dendrobium nobile) SOC1/TM3-Like Ortholog, DnAGL19, in Arabidopsis Regulates HOS1-FT Expression.

    PubMed

    Liu, Xiao-Ru; Pan, Ting; Liang, Wei-Qi; Gao, Lan; Wang, Xiao-Jing; Li, Hong-Qing; Liang, Shan

    2016-01-01

    Flowering in the appropriate season is critical for successful reproduction in angiosperms. The orchid species, Dendrobium nobile, requires vernalization to achieve flowering in the spring, but the underlying regulatory network has not been identified to date. The MADS-box transcription factor DnAGL19 was previously identified in a study of low-temperature treated D. nobile buds and was suggested to regulate vernalization-induced flowering. In this study, phylogenetic analysis of DnAGL9 and the MADS-box containing proteins showed that DnAGL19 is phylogenetically closely related to the SOC1-like protein from orchid Dendrobium Chao Parya Smile, DOSOC1. The orchid clade closed to but is not included into the SOC1-1/TM3 clades associated with either eudicots or monocots, suggesting that DnAGL19 is an SOC1-1/TM3-like ortholog. DnAGL19 was found to be highly expressed in pseudobulbs, leaves, roots, and axillary buds but rarely in flowers, and to be substantially upregulated in axillary buds by prolonged low-temperature treatments. Overexpression of DnAGL19 in Arabidopsis thaliana resulted in a small but significantly reduced time to bolting, suggesting that flowering time was slightly accelerated under normal growth conditions. Consistent with this, the A. thaliana APETELA1 (AP1) gene was expressed at an earlier stage in transgenic lines than in wild type plants, while the FLOWERING LOCUS T (FT) gene was suppressed, suggesting that altered regulations on these transcription factors caused the weak promotion of flowering. HIGH EXPRESSION OF OSMOTICALLY RESPONSIVE GENE 1 (HOS1) was slightly activated under the same conditions, suggesting that the HOS1-FT module may be involved in the DnAGL19-related network. Under vernalization conditions, FT expression was significantly upregulated, whereas HOS1 expression in the transgenic A. thaliana has a level similar to that in wild type. Taken together, these results suggest that DnAGL19 controls the action of the HOS1-FT module

  10. Overexpression of an Orchid (Dendrobium nobile) SOC1/TM3-Like Ortholog, DnAGL19, in Arabidopsis Regulates HOS1-FT Expression

    PubMed Central

    Liu, Xiao-Ru; Pan, Ting; Liang, Wei-Qi; Gao, Lan; Wang, Xiao-Jing; Li, Hong-Qing; Liang, Shan

    2016-01-01

    Flowering in the appropriate season is critical for successful reproduction in angiosperms. The orchid species, Dendrobium nobile, requires vernalization to achieve flowering in the spring, but the underlying regulatory network has not been identified to date. The MADS-box transcription factor DnAGL19 was previously identified in a study of low-temperature treated D. nobile buds and was suggested to regulate vernalization-induced flowering. In this study, phylogenetic analysis of DnAGL9 and the MADS-box containing proteins showed that DnAGL19 is phylogenetically closely related to the SOC1-like protein from orchid Dendrobium Chao Parya Smile, DOSOC1. The orchid clade closed to but is not included into the SOC1-1/TM3 clades associated with either eudicots or monocots, suggesting that DnAGL19 is an SOC1-1/TM3-like ortholog. DnAGL19 was found to be highly expressed in pseudobulbs, leaves, roots, and axillary buds but rarely in flowers, and to be substantially upregulated in axillary buds by prolonged low-temperature treatments. Overexpression of DnAGL19 in Arabidopsis thaliana resulted in a small but significantly reduced time to bolting, suggesting that flowering time was slightly accelerated under normal growth conditions. Consistent with this, the A. thaliana APETELA1 (AP1) gene was expressed at an earlier stage in transgenic lines than in wild type plants, while the FLOWERING LOCUS T (FT) gene was suppressed, suggesting that altered regulations on these transcription factors caused the weak promotion of flowering. HIGH EXPRESSION OF OSMOTICALLY RESPONSIVE GENE 1 (HOS1) was slightly activated under the same conditions, suggesting that the HOS1-FT module may be involved in the DnAGL19-related network. Under vernalization conditions, FT expression was significantly upregulated, whereas HOS1 expression in the transgenic A. thaliana has a level similar to that in wild type. Taken together, these results suggest that DnAGL19 controls the action of the HOS1-FT module

  11. Effect of plasmolysis on protocorm-like bodies of Dendrobium Bobby Messina orchid following cryopreservation with encapsulation-dehydration method.

    PubMed

    Antony, Jessica Jeyanthi James; Mubbarakh, Safiah Ahmad; Mahmood, Maziah; Subramaniam, Sreeramanan

    2014-02-01

    Histological observation and scanning electron microscopy analyses in Dendrobium Bobby Messina indicates the cellular process of cryopreserved protocorm-like bodies (PLBs) was different comparative to non-cryopreserved PLBs. The cellular process was not only modified by the freezing and thawing effect but also due to the dehydration process itself during the cryopreservation procedure. Histological observation in Dendrobium Bobby Messina in encapsulation-dehydration method indicated that the degree of plasmolysis causes more cellular changes to the cryopreserved PLBs comparative to non-cryopreserved and stock culture PLBs. These results revealed higher amount of homogenous cell population and denser cytoplasm in cryopreserved PLBs. Histological analysis also revealed more voluminous nucleus in cryopreserved PLBs comparative to non-cryopreserved PLBs and PLBs stock culture. In contrast, scanning electron microscope analysis showed severe damages in cryopreserved PLBs and non-cryopreserved PLBs comparative to the PLBs stock culture which in return could be the possible reason of no regrowth in encapsulation-dehydration method. Damages incurred were on top part, side part, and at the stomata of the PLBs. Histological observation and scanning electron microscopy analyses in Dendrobium Bobby Messina indicates that the degree of plasmolysis causes changes in the cellular process of PLBs from cryopreserved PLBs was different comparative to non-cryopreserved PLBs. PMID:24218184

  12. An effective nutrient medium for asymbiotic seed germination and large-scale in vitro regeneration of Dendrobium hookerianum, a threatened orchid of northeast India

    PubMed Central

    Paul, Sumi; Kumaria, Suman; Tandon, Pramod

    2012-01-01

    Background and aims Dendrobium hookerianum is a rare and threatened epiphytic orchid of northeast India. Prospects for conservation would be strengthened by developing an in vitro method for mass propagation. Seeds are minute and difficult to use directly in the field for this purpose, being non-endospermous with a low nutrient content and dependent on a specific fungus for germination and early seedling development. Although produced in large numbers (2–3 million per capsule), <5 % germinate naturally in the wild. Our objective was to develop a rapid and successful method for in vitro propagation based on an initial in vitro asymbiotic seed germination step that achieved high percentages. Methodology Effects of four different media, i.e. (i) Murashige and Skoog (MS), (ii) Mitra et al., (iii) Knudson (KC) and (iv) Gamborg et al. (B5), were evaluated for large-scale multiplication by asymbiotic seed germination. Seedling leaf number, shoot number, shoot length, root number and root length were scored. After 7–8 months, large numbers of well-rooted plantlets were transferred to a glasshouse in thermocol pots containing compost. Six different composts based on broken brick and charcoal were compared for their ability to support further development over 90 days of hardening. Principal results The fastest and highest percentage seed germination was achieved using MS medium. Seeds on MS medium germinated in 3–4 weeks compared with 7–8 weeks on B5 medium. Seedling development was also superior on MS medium. The inclusion of plant growth regulators was unnecessary. Compost comprising broken brick and charcoal with an upper layer of moss was found to be the most suitable for the survival of transferred plantlets. Ninety per cent survival of plantlets was achieved 90 days after transfer to a glasshouse. Conclusions The use of MS culture medium is well suited for the mass multiplication of D. hookerianum plants intended for re-introducing this threatened orchid into

  13. Dendrobium micropropagation: a review.

    PubMed

    da Silva, Jaime A Teixeira; Cardoso, Jean Carlos; Dobránszki, Judit; Zeng, Songjun

    2015-05-01

    Dendrobium is one of the largest and most important (ornamentally and medicinally) orchid genera. Tissue culture is now an established method for the effective propagation of members of this genus. This review provides a detailed overview of the Dendrobium micropropagation literature. Through a chronological analysis, aspects such as explant, basal medium, plant growth regulators, culture conditions and final organogenic outcome are chronicled in detail. This review will allow Dendrobium specialists to use the information that has been documented to establish, more efficiently, protocols for their own germplasm and to improve in vitro culture conditions based on the optimized parameters detailed in this review. Not only will this expand the use for mass propagation, but will also allow for the conservation of important germplasm. Information on the in vitro responses of Dendrobium for developing efficient protocols for breeding techniques based on tissue culture, such as polyploidization, somatic hybridization, isolation of mutants and somaclonal variants and for synthetic seed and bioreactor technology, or for genetic transformation, is discussed in this review. This is the first such review on this genus and represents half a decade of literature dedicated to Dendrobium micropropagation. PMID:26046143

  14. In vitro conservation of Dendrobium germplasm.

    PubMed

    Teixeira da Silva, Jaime A; Zeng, Songjun; Galdiano, Renato Fernandes; Dobránszki, Judit; Cardoso, Jean Carlos; Vendrame, Wagner A

    2014-09-01

    Dendrobium is a large genus in the family Orchidaceae that exhibits vast diversity in floral characteristics, which is of considerable importance to orchid breeders, biotechnologists and collectors. Native species have high value as a result of their medicinal properties, while their hybrids are important as ornamental commodities, either as cut flowers or potted plants and are thus veritable industrial crops. Thus, preservation of Dendrobium germplasm is valuable for species conservation, breeding programs and the floriculture industry. Cryopreservation represents the only safe, efficient and cost-effective long-term storage option to facilitate the conservation of genetic resources of plant species. This review highlights 16 years of literature related to the preservation of Dendrobium germplasm and comprises the most comprehensive assessment of thorough studies performed to date, which shows reliable and reproducible results. Air-drying, encapsulation-dehydration, encapsulation-vitrification, vitrification and droplet-vitrification are the current cryopreservation methodologies that have been used to cryopreserve Dendrobium germplasm. Mature seeds, pollen, protoplasts, shoot primordia, protocorms and somatic embryos or protocorm-like bodies (PLBs) have been cryopreserved with different levels of success. Encapsulation-vitrification and encapsulation-dehydration are the most used protocol, while PLBs represent the main explant explored. PMID:24845051

  15. Asymbiotic in vitro seed propagation of Dendrobium.

    PubMed

    Teixeira da Silva, Jaime A; Tsavkelova, Elena A; Ng, Tzi Bun; Parthibhan, S; Dobránszki, Judit; Cardoso, Jean Carlos; Rao, M V; Zeng, Songjun

    2015-10-01

    The ability to germinate orchids from seeds in vitro presents a useful and viable method for the propagation of valuable germplasm, maintaining the genetic heterogeneity inherent in seeds. Given the ornamental and medicinal importance of many species within the genus Dendrobium, this review explores in vitro techniques for their asymbiotic seed germination. The influence of abiotic factors (such as temperature and light), methods of sterilization, composition of basal media, and supplementation with organic additives and plant growth regulators are discussed in context to achieve successful seed germination, protocorm formation, and further seedling growth and development. This review provides both a basis for the selection of optimal conditions, and a platform for the discovery of better ones, that would allow the development of new protocols and the exploration of new hypotheses for germination and conservation of Dendrobium seeds and seedlings. PMID:26183950

  16. Australian orchids and the doctors they commemorate.

    PubMed

    Pearn, John H

    2013-01-21

    Botanical taxonomy is a repository of medical biographical information. Such botanical memorials include the names of some indigenous orchids of Australia. By searching reference texts and journals relating to Australian botany and Australian orchidology, as well as Australian and international medical and botanical biographical texts, I identified 30 orchids indigenous to Australia whose names commemorate doctors and other medical professionals. Of these, 24 have names that commemorate a total of 16 doctors who worked in Australia. The doctors and orchids I identified include: doctor-soldiers Richard Sanders Rogers (1862-1942), after whom the Rogers' Greenhood (Pterostylis rogersii) is named, and Robert Brown (1773-1858), after whom the Purple Enamel Orchid (Elythranthera brunonis) is named; navy surgeon Archibald Menzies (1754-1842), after whom the Hare Orchid (Leptoceras menziesii) is named; radiologist Hugo Flecker (1884-1957) after whom the Slender Sphinx Orchid (Cestichis fleckeri) is named; and general medical practitioner Hereward Leighton Kesteven (1881-1964), after whom the Kesteven's Orchid (Dendrobium kestevenii) is named. Biographic references in scientific names of plants comprise a select but important library of Australian medical history. Such botanical taxonomy commemorates, in an enduring manner, clinicians who have contributed to biology outside clinical practice. PMID:23330773

  17. Orchid Fever

    ERIC Educational Resources Information Center

    Oliver, Phillip

    2004-01-01

    Exotic, captivating, and seductive, orchids have long fascinated plant lovers. They first attracted the attention of Westerners in the 17th century, when explorers brought back samples from South America and Asia. By the mid-1800s, orchid collecting had reached a fever pitch, not unlike that of the Dutch tulip craze of the 1630s, with rich (and…

  18. Comparative molecular cytogenetics of major repetitive sequence families of three Dendrobium species (Orchidaceae) from Bangladesh

    PubMed Central

    Begum, Rabeya; Alam, Sheikh Shamimul; Menzel, Gerhard; Schmidt, Thomas

    2009-01-01

    Background and Aims Dendrobium species show tremendous morphological diversity and have broad geographical distribution. As repetitive sequence analysis is a useful tool to investigate the evolution of chromosomes and genomes, the aim of the present study was the characterization of repetitive sequences from Dendrobium moschatum for comparative molecular and cytogenetic studies in the related species Dendrobium aphyllum, Dendrobium aggregatum and representatives from other orchid genera. Methods In order to isolate highly repetitive sequences, a c0t-1 DNA plasmid library was established. Repeats were sequenced and used as probes for Southern hybridization. Sequence divergence was analysed using bioinformatic tools. Repetitive sequences were localized along orchid chromosomes by fluorescence in situ hybridization (FISH). Key Results Characterization of the c0t-1 library resulted in the detection of repetitive sequences including the (GA)n dinucleotide DmoO11, numerous Arabidopsis-like telomeric repeats and the highly amplified dispersed repeat DmoF14. The DmoF14 repeat is conserved in six Dendrobium species but diversified in representative species of three other orchid genera. FISH analyses showed the genome-wide distribution of DmoF14 in D. moschatum, D. aphyllum and D. aggregatum. Hybridization with the telomeric repeats demonstrated Arabidopsis-like telomeres at the chromosome ends of Dendrobium species. However, FISH using the telomeric probe revealed two pairs of chromosomes with strong intercalary signals in D. aphyllum. FISH showed the terminal position of 5S and 18S–5·8S–25S rRNA genes and a characteristic number of rDNA sites in the three Dendrobium species. Conclusions The repeated sequences isolated from D. moschatum c0t-1 DNA constitute major DNA families of the D. moschatum, D. aphyllum and D. aggregatum genomes with DmoF14 representing an ancient component of orchid genomes. Large intercalary telomere-like arrays suggest chromosomal

  19. Advances in Dendrobium molecular research: Applications in genetic variation, identification and breeding.

    PubMed

    Teixeira da Silva, Jaime A; Jin, Xiaohua; Dobránszki, Judit; Lu, Jiangjie; Wang, Huizhong; Zotz, Gerhard; Cardoso, Jean Carlos; Zeng, Songjun

    2016-02-01

    Orchids of the genus Dendrobium are of great economic importance in global horticultural trade and in Asian traditional medicine. For both areas, research yielding solid information on taxonomy, phylogeny, and breeding of this genus are essential. Traditional morphological and cytological characterization are used in combination with molecular results in classification and identification. Markers may be useful when used alone but are not always reliable in identification. The number of species studied and identified by molecular markers is small at present. Conventional breeding methods are time-consuming and laborious. In the past two decades, promising advances have been made in taxonomy, phylogeny and breeding of Dendrobium species due to the intensive use of molecular markers. In this review, we focus on the main molecular techniques used in 121 published studies and discuss their importance and possibilities in speeding up the breeding of new cultivars and hybrids. PMID:26493228

  20. Pseudopollen in Dendrobium unicum Seidenf. (Orchidaceae): Reward or Deception?

    PubMed Central

    DAVIES, K. L.; TURNER, M. P.

    2004-01-01

    • Background and Aims In 1987, Kjellsson and Rasmussen described the labellar trichomes of Dendrobium unicum Seidenf. and proposed that these hairs function as pseudopollen. Pseudopollen is a mealy material that superficially resembles pollen, is usually laden with food substances and is formed when labellar hairs either fragment into individual cells or become detached from the labellum. However, the trichomes of D. unicum are very different from pseudopollen‐forming hairs found in other orchid genera such as Maxillaria and Polystachya. Moreover, Kjellsson and Rasmussen were unable to demonstrate the presence of food substances within these trichomes and argued that even in the absence of food substances, the hairs, in that they superficially resemble pollen, can still attract insects by deceit. The aim of this paper is to investigate whether the labellar trichomes of D. unicum contain food reserves and thus reward potential pollinators or whether they are devoid of foods and attract insects solely by mimicry. • Methods Light microscopy, histochemistry and transmission electron microscopy. • Key Results Dendrobium unicum produces pseudopollen. Pseudopollen here, however, differs from that previously described for other orchid genera in that the pseudopollen‐forming trichomes consist of a stalk cell and a ‘head’ of component cells that separate at maturity, in contrast to Maxillaria and some Polystachya spp. where pseudopollen is formed by the fragmentation of moniliform hairs. Moreover, the pseudopollen of Maxillaria and Polystachya largely contains protein, whereas in D. unicum the main food substance is starch. • Conclusions Flowers of D. unicum, rather than attracting insects solely by deceit may also reward potential pollinators. PMID:15159216

  1. Orchid flowers tolerance to gamma-radiation

    NASA Astrophysics Data System (ADS)

    Kikuchi, Olivia Kimiko

    2000-03-01

    Cut flowers are fresh goods that may be treated with fumigants such as methyl bromide to meet the needs of the quarantine requirements of importing countries. Irradiation is a non-chemical alternative to substitute the methyl bromide treatment of fresh products. In this research, different cut orchids were irradiated to examine their tolerance to gamma-rays. A 200 Gy dose did inhibit the Dendrobium palenopsis buds from opening, but did not cause visible damage to opened flowers. Doses of 800 and 1000 Gy were damaging because they provoked the flowers to drop from the stem. Cattleya irradiated with 750 Gy did not show any damage, and were therefore eligible for the radiation treatment. Cymbidium tolerated up to 300 Gy and above this dose dropped prematurely. On the other hand, Oncydium did not tolerate doses above 150 Gy.

  2. Symbiotic in vitro seed propagation of Dendrobium: fungal and bacterial partners and their influence on plant growth and development.

    PubMed

    Teixeira da Silva, Jaime A; Tsavkelova, Elena A; Zeng, Songjun; Ng, Tzi Bun; Parthibhan, S; Dobránszki, Judit; Cardoso, Jean Carlos; Rao, M V

    2015-07-01

    The genus Dendrobium is one of the largest genera of the Orchidaceae Juss. family, although some of its members are the most threatened today. The reason why many species face a vulnerable or endangered status is primarily because of anthropogenic interference in natural habitats and commercial overexploitation. The development and application of modern techniques and strategies directed towards in vitro propagation of orchids not only increases their number but also provides a viable means to conserve plants in an artificial environment, both in vitro and ex vitro, thus providing material for reintroduction. Dendrobium seed germination and propagation are challenging processes in vivo and in vitro, especially when the extreme specialization of these plants is considered: (1) their biotic relationships with pollinators and mycorrhizae; (2) adaptation to epiphytic or lithophytic life-styles; (3) fine-scale requirements for an optimal combination of nutrients, light, temperature, and pH. This review also aims to summarize the available data on symbiotic in vitro Dendrobium seed germination. The influence of abiotic factors as well as composition and amounts of different exogenous nutrient substances is examined. With a view to better understanding how to optimize and control in vitro symbiotic associations, a part of the review describes the strong biotic relations of Dendrobium with different associative microorganisms that form microbial communities with adult plants, and also influence symbiotic seed germination. The beneficial role of plant growth-promoting bacteria is also discussed. PMID:25940846

  3. Seedling development and evaluation of genetic stability of cryopreserved Dendrobium hybrid mature seeds.

    PubMed

    Galdiano, Renato Fernandes; de Macedo Lemos, Eliana Gertrudes; de Faria, Ricardo Tadeu; Vendrame, Wagner Aparecido

    2014-03-01

    Vitrification, a simple, fast, and recommended cryopreservation method for orchid germplasm conservation, was evaluated for Dendrobium hybrid "Dong Yai" mature seeds. The genetic stability of regenerated seedlings was also evaluated using flow cytometry. Mature seeds from this hybrid were submitted to plant vitrification solution (PVS2) for 0, 0.5, 1, 2, 3, 4, 5, or 6 h at 0 °C. Subsequently, they were plunged into liquid nitrogen (LN) at -196 °C for 1 h and recovered in half-strength Murashige and Skoog culture medium (1/2 MS), and seed germination was evaluated after 30 days. Seeds directly submitted to LN did not germinate after cryopreservation. Seeds treated with PVS2 between 1 and 3 h presented the best germination (between 51 and 58%), although longer exposure to PVS2 returned moderated germination (39%). Germinated seeds were further subcultured in P-723 culture medium and developed whole seedlings in vitro after 180 days, with no abnormal characteristics, diseases, or nutritional deficiencies. Seedlings were successfully acclimatized under greenhouse conditions with over 80% survival. Flow cytometry analysis revealed no chromosomal changes on vitrified seedlings, as well as seedlings germinated from the control treatment (direct exposure to LN). These findings indicate that vitrification is a feasible and safe germplasm cryopreservation method for commercial Dendrobium orchid hybrid conservation. PMID:24402568

  4. The Dendrobium catenatum Lindl. genome sequence provides insights into polysaccharide synthase, floral development and adaptive evolution.

    PubMed

    Zhang, Guo-Qiang; Xu, Qing; Bian, Chao; Tsai, Wen-Chieh; Yeh, Chuan-Ming; Liu, Ke-Wei; Yoshida, Kouki; Zhang, Liang-Sheng; Chang, Song-Bin; Chen, Fei; Shi, Yu; Su, Yong-Yu; Zhang, Yong-Qiang; Chen, Li-Jun; Yin, Yayi; Lin, Min; Huang, Huixia; Deng, Hua; Wang, Zhi-Wen; Zhu, Shi-Lin; Zhao, Xiang; Deng, Cao; Niu, Shan-Ce; Huang, Jie; Wang, Meina; Liu, Guo-Hui; Yang, Hai-Jun; Xiao, Xin-Ju; Hsiao, Yu-Yun; Wu, Wan-Lin; Chen, You-Yi; Mitsuda, Nobutaka; Ohme-Takagi, Masaru; Luo, Yi-Bo; Van de Peer, Yves; Liu, Zhong-Jian

    2016-01-01

    Orchids make up about 10% of all seed plant species, have great economical value, and are of specific scientific interest because of their renowned flowers and ecological adaptations. Here, we report the first draft genome sequence of a lithophytic orchid, Dendrobium catenatum. We predict 28,910 protein-coding genes, and find evidence of a whole genome duplication shared with Phalaenopsis. We observed the expansion of many resistance-related genes, suggesting a powerful immune system responsible for adaptation to a wide range of ecological niches. We also discovered extensive duplication of genes involved in glucomannan synthase activities, likely related to the synthesis of medicinal polysaccharides. Expansion of MADS-box gene clades ANR1, StMADS11, and MIKC(*), involved in the regulation of development and growth, suggests that these expansions are associated with the astonishing diversity of plant architecture in the genus Dendrobium. On the contrary, members of the type I MADS box gene family are missing, which might explain the loss of the endospermous seed. The findings reported here will be important for future studies into polysaccharide synthesis, adaptations to diverse environments and flower architecture of Orchidaceae. PMID:26754549

  5. The Dendrobium catenatum Lindl. genome sequence provides insights into polysaccharide synthase, floral development and adaptive evolution

    PubMed Central

    Zhang, Guo-Qiang; Xu, Qing; Bian, Chao; Tsai, Wen-Chieh; Yeh, Chuan-Ming; Liu, Ke-Wei; Yoshida, Kouki; Zhang, Liang-Sheng; Chang, Song-Bin; Chen, Fei; Shi, Yu; Su, Yong-Yu; Zhang, Yong-Qiang; Chen, Li-Jun; Yin, Yayi; Lin, Min; Huang, Huixia; Deng, Hua; Wang, Zhi-Wen; Zhu, Shi-Lin; Zhao, Xiang; Deng, Cao; Niu, Shan-Ce; Huang, Jie; Wang, Meina; Liu, Guo-Hui; Yang, Hai-Jun; Xiao, Xin-Ju; Hsiao, Yu-Yun; Wu, Wan-Lin; Chen, You-Yi; Mitsuda, Nobutaka; Ohme-Takagi, Masaru; Luo, Yi-Bo; Van de Peer, Yves; Liu, Zhong-Jian

    2016-01-01

    Orchids make up about 10% of all seed plant species, have great economical value, and are of specific scientific interest because of their renowned flowers and ecological adaptations. Here, we report the first draft genome sequence of a lithophytic orchid, Dendrobium catenatum. We predict 28,910 protein-coding genes, and find evidence of a whole genome duplication shared with Phalaenopsis. We observed the expansion of many resistance-related genes, suggesting a powerful immune system responsible for adaptation to a wide range of ecological niches. We also discovered extensive duplication of genes involved in glucomannan synthase activities, likely related to the synthesis of medicinal polysaccharides. Expansion of MADS-box gene clades ANR1, StMADS11, and MIKC*, involved in the regulation of development and growth, suggests that these expansions are associated with the astonishing diversity of plant architecture in the genus Dendrobium. On the contrary, members of the type I MADS box gene family are missing, which might explain the loss of the endospermous seed. The findings reported here will be important for future studies into polysaccharide synthesis, adaptations to diverse environments and flower architecture of Orchidaceae. PMID:26754549

  6. Fusarium Wilt of Orchids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium wilt of orchids is highly destructive and economically limiting to the production of quality orchids that has steadily increased in many production facilities. Important crops such as phalaenopsis, cattleyas, and oncidiums appear to be especially susceptible to certain Fusarium species. Fu...

  7. Transitions between self-compatibility and self-incompatibility and the evolution of reproductive isolation in the large and diverse tropical genus Dendrobium (Orchidaceae)

    PubMed Central

    Pinheiro, Fabio; Cafasso, Donata; Cozzolino, Salvatore; Scopece, Giovanni

    2015-01-01

    Background and Aims The evolution of interspecific reproductive barriers is crucial to understanding species evolution. This study examines the contribution of transitions between self-compatibility (SC) and self-incompatibility (SI) and genetic divergence in the evolution of reproductive barriers in Dendrobium, one of the largest orchid genera. Specifically, it investigates the evolution of pre- and postzygotic isolation and the effects of transitions between compatibility states on interspecific reproductive isolation within the genus. Methods The role of SC and SI changes in reproductive compatibility among species was examined using fruit set and seed viability data available in the literature from 86 species and ∼2500 hand pollinations. The evolution of SC and SI in Dendrobium species was investigated within a phylogenetic framework using internal transcribed spacer sequences available in GenBank. Key Results Based on data from crossing experiments, estimations of genetic distance and the results of a literature survey, it was found that changes in SC and SI significantly influenced the compatibility between species in interspecific crosses. The number of fruits produced was significantly higher in crosses in which self-incompatible species acted as pollen donor for self-compatible species, following the SI × SC rule. Maximum likelihood and Bayesian tests did not reject transitions from SI to SC and from SC to SI across the Dendrobium phylogeny. In addition, postzygotic isolation (embryo mortality) was found to evolve gradually with genetic divergence, in agreement with previous results observed for other plant species, including orchids. Conclusions Transitions between SC and SI and the gradual accumulation of genetic incompatibilities affecting postzygotic isolation are important mechanisms preventing gene flow among Dendrobium species, and may constitute important evolutionary processes contributing to the high levels of species diversity in this

  8. Molecular phylogenetics and character evolution of morphologically diverse groups, Dendrobium section Dendrobium and allies

    PubMed Central

    Takamiya, Tomoko; Wongsawad, Pheravut; Sathapattayanon, Apirada; Tajima, Natsuko; Suzuki, Shunichiro; Kitamura, Saki; Shioda, Nao; Handa, Takashi; Kitanaka, Susumu; Iijima, Hiroshi; Yukawa, Tomohisa

    2014-01-01

    It is always difficult to construct coherent classification systems for plant lineages having diverse morphological characters. The genus Dendrobium, one of the largest genera in the Orchidaceae, includes ∼1100 species, and enormous morphological diversification has hindered the establishment of consistent classification systems covering all major groups of this genus. Given the particular importance of species in Dendrobium section Dendrobium and allied groups as floriculture and crude drug genetic resources, there is an urgent need to establish a stable classification system. To clarify phylogenetic relationships in Dendrobium section Dendrobium and allied groups, we analysed the macromolecular characters of the group. Phylogenetic analyses of 210 taxa of Dendrobium were conducted on DNA sequences of internal transcribed spacer (ITS) regions of 18S–26S nuclear ribosomal DNA and the maturase-coding gene (matK) located in an intron of the plastid gene trnK using maximum parsimony and Bayesian methods. The parsimony and Bayesian analyses revealed 13 distinct clades in the group comprising section Dendrobium and its allied groups. Results also showed paraphyly or polyphyly of sections Amblyanthus, Aporum, Breviflores, Calcarifera, Crumenata, Dendrobium, Densiflora, Distichophyllae, Dolichocentrum, Holochrysa, Oxyglossum and Pedilonum. On the other hand, the monophyly of section Stachyobium was well supported. It was found that many of the morphological characters that have been believed to reflect phylogenetic relationships are, in fact, the result of convergence. As such, many of the sections that have been recognized up to this point were found to not be monophyletic, so recircumscription of sections is required. PMID:25107672

  9. Metabolic Analysis of Medicinal Dendrobium officinale and Dendrobium huoshanense during Different Growth Years

    PubMed Central

    Jin, Qing; Jiao, Chunyan; Sun, Shiwei; Song, Cheng; Cai, Yongping; Lin, Yi; Fan, Honghong; Zhu, Yanfang

    2016-01-01

    Metabolomics technology has enabled an important method for the identification and quality control of Traditional Chinese Medical materials. In this study, we isolated metabolites from cultivated Dendrobium officinale and Dendrobium huoshanense stems of different growth years in the methanol/water phase and identified them using gas chromatography coupled with mass spectrometry (GC-MS). First, a metabolomics technology platform for Dendrobium was constructed. The metabolites in the Dendrobium methanol/water phase were mainly sugars and glycosides, amino acids, organic acids, alcohols. D. officinale and D. huoshanense and their growth years were distinguished by cluster analysis in combination with multivariate statistical analysis, including principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA). Eleven metabolites that contributed significantly to this differentiation were subjected to t-tests (P<0.05) to identify biomarkers that discriminate between D. officinale and D. huoshanense, including sucrose, glucose, galactose, succinate, fructose, hexadecanoate, oleanitrile, myo-inositol, and glycerol. Metabolic profiling of the chemical compositions of Dendrobium species revealed that the polysaccharide content of D. huoshanense was higher than that of D. officinale, indicating that the D. huoshanense was of higher quality. Based on the accumulation of Dendrobium metabolites, the optimal harvest time for Dendrobium was in the third year. This initial metabolic profiling platform for Dendrobium provides an important foundation for the further study of secondary metabolites (pharmaceutical active ingredients) and metabolic pathways. PMID:26752292

  10. [Dendrobium officinale stereoscopic cultivation method].

    PubMed

    Si, Jin-Ping; Dong, Hong-Xiu; Liao, Xin-Yan; Zhu, Yu-Qiu; Li, Hui

    2014-12-01

    The study is aimed to make the most of available space of Dendrobium officinale cultivation facility, reveal the yield and functional components variation of stereoscopic cultivated D. officinale, and improve quality, yield and efficiency. The agronomic traits and yield variation of stereoscopic cultivated D. officinale were studied by operating field experiment. The content of polysaccharide and extractum were determined by using phenol-sulfuric acid method and 2010 edition of "Chinese Pharmacopoeia" Appendix X A. The results showed that the land utilization of stereoscopic cultivated D. officinale increased 2.74 times, the stems, leaves and their total fresh or dry weight in unit area of stereoscopic cultivated D. officinale were all heavier than those of the ground cultivated ones. There was no significant difference in polysaccharide content between stereoscopic cultivation and ground cultivation. But the extractum content and total content of polysaccharide and extractum were significantly higher than those of the ground cultivated ones. In additional, the polysaccharide content and total content of polysaccharide and extractum from the top two levels of stereoscopic culture matrix were significantly higher than that of the ones from the other levels and ground cultivation. Steroscopic cultivation can effectively improves the utilization of space and yield, while the total content of polysaccharides and extractum were significantly higher than that of the ground cultivated ones. The significant difference in Dendrobium polysaccharides among the plants from different height of stereo- scopic culture matrix may be associated with light factor. PMID:25911804

  11. Catalase and superoxide dismutase activities and the total protein content of protocorm-like bodies of Dendrobium sonia-28 subjected to vitrification.

    PubMed

    Poobathy, Ranjetta; Sinniah, Uma Rani; Xavier, Rathinam; Subramaniam, Sreeramanan

    2013-07-01

    Dendrobium sonia-28 is an important ornamental orchid in the Malaysian flower industry. However, the genus faces both low germination rates and the risk of producing heterozygous progenies. Cryopreservation is currently the favoured long-term storage method for orchids with propagation problems. Vitrification, a frequently used cryopreservation technique, involves the application of pretreatments and cryoprotectants to protect and recover explants during and after storage in liquid nitrogen. However, cryopreservation may cause osmotic injuries and toxicity to cryopreserved explants from the use of highly concentrated additives, and cellular injuries from thawing, devitrification and ice formation. Reactive oxygen species (ROS), occurring during dehydration and cryopreservation, may also cause membrane damage. Plants possess efficient antioxidant systems such as the superoxide dismutase (SOD) and catalase (CAT) enzymes to scavenge ROS during low temperature stress. In this study, protocorm-like bodies (PLBs) of Dendrobium sonia-28 were assayed for the total protein content, and both SOD and CAT activities, at each stage of a vitrification exercise to observe for deleterious stages in the protocol. The results indicated that cryopreserved PLBs of Dendrobium sonia-28 underwent excessive post-thawing oxidative stress due to decreased levels of the CAT enzyme at the post-thawing recovery stage, which contributed to the poor survival rates of the cryopreserved PLBs. PMID:23640259

  12. Antitumor Activity of Ethanolic Extract of Dendrobium formosum in T-Cell Lymphoma: An In Vitro and In Vivo Study

    PubMed Central

    Prasad, Ritika; Koch, Biplob

    2014-01-01

    Dendrobium, a genus of orchid, was found to possess useful therapeutic activities like anticancer, hypoglycaemic, antimicrobial, immunomodulatory, hepatoprotective, antioxidant, and neuroprotective activities. The study was aimed to evaluate the anticancer property of the ethanolic extract of Dendrobium formosum on Dalton's lymphoma. In vitro cytotoxicity was determined by MTT assay, apoptosis was determined by fluorescence microscopy, and cell cycle progression was analysed using flow cytometry; in vivo antitumor activity was performed in Dalton's lymphoma bearing mice. The IC50 value of ethanolic extract was obtained at 350 μg/mL in Dalton's lymphoma cells. Fluorescence microscopy analysis showed significant increase in apoptotic cell death in dose- and time-dependent manner which was further confirmed through the resulting DNA fragmentation. Further, flow cytometry analysis showed that the ethanolic extract arrests the cells in G2/M phase of the cell cycle. The in vivo anticancer activity study illustrates significant increase in the survival time of Dalton's lymphoma bearing mice on treatment with ethanolic extract when compared to control. These results substantiate the antitumor properties of ethanolic extract of Dendrobium formosum and suggest an alternative in treatment of cancer. Further studies are required regarding the isolation and characterization of bioactive components along with the analysis of molecular mechanism involved. PMID:24959588

  13. Establishment of an Efficient In Vitro Regeneration Protocol for Rapid and Mass Propagation of Dendrobium chrysotoxum Lindl. Using Seed Culture

    PubMed Central

    2014-01-01

    An efficient in vitro regeneration protocol from seed culture has been established successfully for Dendrobium chrysotoxum, an epiphytic orchid having tremendous ornamental and medicinal values. Seed germination response was encouraging in Mitra (M) medium enriched with different combinations of auxins and cytokinins. Medium supplemented with 0.4% activated charcoal (AC), 2 mg/L 6-benzyl amino purine (BAP), and 2 mg/L indole-3-acetic acid (IAA) produced best seed germination percentage in 2 weeks of culture. Incorporation of higher concentration of kinetin (KN) or BAP in combination with low auxin in medium induced pronounced shooting and leaf formation. Reduction in leaf development was evident when cytokinins exist singly in medium indicating synergistic effect of auxin and cytokinin in leaf induction. Presence of elevated level of indole-3-butyric acid (IBA) or 1-naphthalene acetic acid (NAA) with low cytokinin content in medium generated more in vitro rooting, though IBA was found to be more effective in rooting induction as compared to NAA. The in vitro protocol for asymbiotic seed germination developed from the present investigation can be used for rapid mass propagation of this highly important Dendrobium orchid species. PMID:25401154

  14. Establishment of an efficient in vitro regeneration protocol for rapid and mass propagation of Dendrobium chrysotoxum Lindl. using seed culture.

    PubMed

    Nongdam, Potshangbam; Tikendra, Leimapokpam

    2014-01-01

    An efficient in vitro regeneration protocol from seed culture has been established successfully for Dendrobium chrysotoxum, an epiphytic orchid having tremendous ornamental and medicinal values. Seed germination response was encouraging in Mitra (M) medium enriched with different combinations of auxins and cytokinins. Medium supplemented with 0.4% activated charcoal (AC), 2 mg/L 6-benzyl amino purine (BAP), and 2 mg/L indole-3-acetic acid (IAA) produced best seed germination percentage in 2 weeks of culture. Incorporation of higher concentration of kinetin (KN) or BAP in combination with low auxin in medium induced pronounced shooting and leaf formation. Reduction in leaf development was evident when cytokinins exist singly in medium indicating synergistic effect of auxin and cytokinin in leaf induction. Presence of elevated level of indole-3-butyric acid (IBA) or 1-naphthalene acetic acid (NAA) with low cytokinin content in medium generated more in vitro rooting, though IBA was found to be more effective in rooting induction as compared to NAA. The in vitro protocol for asymbiotic seed germination developed from the present investigation can be used for rapid mass propagation of this highly important Dendrobium orchid species. PMID:25401154

  15. Two strategies by epiphytic orchids for maintaining water balance: thick cuticles in leaves and water storage in pseudobulbs.

    PubMed

    Yang, Shi-Jian; Sun, Mei; Yang, Qiu-Yun; Ma, Ren-Yi; Zhang, Jiao-Lin; Zhang, Shi-Bao

    2016-01-01

    Epiphytes are an important component of tropical and subtropical flora, and serve vital ecological functions in forest hydrology and nutrient fluxes. However, they often encounter water deficits because there is no direct contact between their roots and the soil. The strategies employed by epiphytes for maintaining water balance in relatively water-limited habitats are not completely understood. In the present study, we investigated the anatomical traits, water loss rates, and physiology of leaves and pseudobulbs of four Dendrobium species with different pseudobulb morphologies to understand the roles of leaf and pseudobulb in maintaining water balance of epiphytic orchids. Our results showed that two species (D. chrysotoxum and D. officinale), with lower rates of water loss, have thicker leaves and upper cuticles, but lower epidermal thickness and leaf dry mass per area. In contrast, the other two species (D. chrysanthum and D. crystallinum) with thinner cuticles and higher rates of water loss, have less tissue density and greater saturated water contents in their pseudobulbs. Therefore, our results indicate that these latter two species may resist drought by storing water in the pseudobulbs to compensate for their thin cuticles and rapid water loss through the leaves. Under the same laboratory conditions, excised pseudobulbs with attached leaves had lower rates of water loss when compared with samples comprising only excised leaves. This implies that epiphytic orchids utilize two different strategies for sustaining water balance: thick cuticles to conserve water in leaves and water storage in pseudobulbs. Our results also show that Dendrobium species with thin cuticles tend to have pseudobulbs with high water storage capacity that compensates for their faster rates of water loss. These outcomes contribute to our understanding of the adaptive water-use strategies in Dendrobium species, which is beneficial for the conservation and cultivation of epiphytic orchids

  16. Two strategies by epiphytic orchids for maintaining water balance: thick cuticles in leaves and water storage in pseudobulbs

    PubMed Central

    Yang, Shi-Jian; Sun, Mei; Yang, Qiu-Yun; Ma, Ren-Yi; Zhang, Jiao-Lin; Zhang, Shi-Bao

    2016-01-01

    Epiphytes are an important component of tropical and subtropical flora, and serve vital ecological functions in forest hydrology and nutrient fluxes. However, they often encounter water deficits because there is no direct contact between their roots and the soil. The strategies employed by epiphytes for maintaining water balance in relatively water-limited habitats are not completely understood. In the present study, we investigated the anatomical traits, water loss rates, and physiology of leaves and pseudobulbs of four Dendrobium species with different pseudobulb morphologies to understand the roles of leaf and pseudobulb in maintaining water balance of epiphytic orchids. Our results showed that two species (D. chrysotoxum and D. officinale), with lower rates of water loss, have thicker leaves and upper cuticles, but lower epidermal thickness and leaf dry mass per area. In contrast, the other two species (D. chrysanthum and D. crystallinum) with thinner cuticles and higher rates of water loss, have less tissue density and greater saturated water contents in their pseudobulbs. Therefore, our results indicate that these latter two species may resist drought by storing water in the pseudobulbs to compensate for their thin cuticles and rapid water loss through the leaves. Under the same laboratory conditions, excised pseudobulbs with attached leaves had lower rates of water loss when compared with samples comprising only excised leaves. This implies that epiphytic orchids utilize two different strategies for sustaining water balance: thick cuticles to conserve water in leaves and water storage in pseudobulbs. Our results also show that Dendrobium species with thin cuticles tend to have pseudobulbs with high water storage capacity that compensates for their faster rates of water loss. These outcomes contribute to our understanding of the adaptive water-use strategies in Dendrobium species, which is beneficial for the conservation and cultivation of epiphytic orchids

  17. A new bibenzyl from Dendrobium secundum.

    PubMed

    Sritularak, Boonchoo; Duangrak, Natthacha; Likhitwitayawuid, Kittisak

    2011-01-01

    From the aerial parts of Dendrobium secundum, a new bibenzyl, namely 4,5,4'-trihydroxy-3,3'-dimethoxybibenzyl, was isolated, along with four known compounds which included brittonin A, moscatilin, syringaresinol, and ferulic acid. All of these isolates showed appreciable DPPH free radical scavenging potential, except for brittonin A, which was devoid of activity. PMID:21812336

  18. Three new bibenzyl derivatives from Dendrobium nobile.

    PubMed

    Zhang, Xue; Gao, Hao; Wang, Nai-Li; Yao, Xin-Sheng

    2006-01-01

    Three new bibenzyl derivatives have been isolated from the stems of Dendrobium nobile Lindl. (Orchidaceae). Their structures were established as 4,5-dihydroxy-3,3',alpha-trimethoxybibenzyl (1), 4,4'-dihydroxy-3,3',5,alpha-tetramethoxybibenzyl (2) and 4-hydroxy-3,3',4',5,alpha-pentamethoxybibenzyl (3) on the basis of spectroscopic analysis. PMID:16753791

  19. [Artificial cultivation modes for Dendrobium officinale].

    PubMed

    Si, Jin-Ping; Yu, Qiao-Xian; Song, Xian-Shui; Shao, Wei-Jiang

    2013-02-01

    Since the beginning of the new century, the artificial cultivation of Dendrobium officinale has made a breakthrough progress. This paper systematically expounds key technologies, main features and cautions of the cultivation modes e.g. bionic-facility cultivation, the original ecological cultivation, and potting cultivation for D. officinale, which can provide useful information for the development and improvement of D. officinale industry. PMID:23713268

  20. DOH1, a Class 1 knox Gene, Is Required for Maintenance of the Basic Plant Architecture and Floral Transition in Orchid

    PubMed Central

    Yu, Hao; Yang, Shu Hua; Goh, Chong Jin

    2000-01-01

    We report here the isolation and identification of an orchid homeobox gene, DOH1, from Dendrobium Madame Thong-In. Analyses of its sequence and genomic organization suggest that DOH1 may be the only class 1 knox gene in the genome. DOH1 mRNA accumulates in meristem-rich tissues, and its expression is greatly downregulated during floral transition. In situ hybridization analysis demonstrates that DOH1 is also expressed in the incipient leaf primordia and is later detected in the same region of the inflorescence apex, as in DOMADS1. Overexpression of DOH1 in orchid plants completely suppresses shoot organization and development. Transgenic orchid plants expressing antisense mRNA for DOH1 show multiple shoot apical meristem (SAM) formations and early flowering. In addition, both the sense and antisense transformants exhibit defects in leaf development. These findings suggest that DOH1 plays a key role in maintaining the basic plant architecture of orchid through control of the formation and development of the SAM and shoot structure. Investigations of DOMADS1 expression in the SAM during floral transition reveal that the precocious flowering phenotype exhibited by DOH1 antisense transformants is coupled with the early onset of DOMADS1 expression. This fact, together with the reciprocal expression of DOH1 and DOMADS1 during floral transition, indicates that downregulation of DOH1 in the SAM is required for floral transition in orchid and that DOH1 is a possible upstream regulator of DOMADS1. PMID:11090215

  1. Four new bibenzyl derivatives from Dendrobium candidum.

    PubMed

    Li, Yan; Wang, Chun-Lan; Wang, Ya-Jun; Wang, Fang-Fei; Guo, Shun-Xing; Yang, Jun-Shan; Xiao, Pei-Gen

    2009-09-01

    Four new bibenzyl derivatives, namely, dendrocandins F-I (1-4), were isolated from the stems of Dendrobium candidum. Their structures were elucidated by the analysis of spectroscopic data. Dendrocandins F and G represent the fourth and fifth example of bisbibenzyl derivates with a dibenzopyran ring between two units, respectively. Dendrocandin H represents the first example of a bibenzyl derivative formed by a bibenzyl and a 1,4-phenanthraquinone unit via a dibenzopyran ring. Compounds 1-4 were examined for antioxidant activity by 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging assay. PMID:19721264

  2. Eight new bibenzyl derivatives from Dendrobium candidum.

    PubMed

    Li, Yan; Wang, Chun-Lan; Zhao, Hai-Jun; Guo, Shun-Xing

    2014-01-01

    Eight bibenzyl derivatives, namely dendrocandins J-Q (1-8), were isolated from the stems of Dendrobium candidum. Their structures were elucidated by 1D and 2D NMR experiments and mass spectrometry. Compounds 1-8 were examined for antioxidant activity by 1,1-diphenyl-2-picrylhydrazyl free radical scavenging assay, and the IC50 values were 36.8, 70.2, 45.0, 60.5, 87.6, 50.4, 22.3, and 30.3 μM, respectively. PMID:25355458

  3. Ethylene and pollination decrease transcript abundance of an ethylene receptor gene in Dendrobium petals.

    PubMed

    Thongkum, Monthathip; Burns, Parichart; Bhunchoth, Anjana; Warin, Nuchnard; Chatchawankanphanich, Orawan; van Doorn, Wouter G

    2015-03-15

    We studied the expression of a gene encoding an ethylene receptor, called Ethylene Response Sensor 1 (Den-ERS1), in the petals of Dendrobium orchid flowers. Transcripts accumulated during the young floral bud stage and declined by the time the flowers had been open for several days. Pollination or exposure to exogenous ethylene resulted in earlier flower senescence, an increase in ethylene production and a lower Den-ERS1 transcript abundance. Treatment with 1-methylcyclopropene (1-MCP), an inhibitor of the ethylene receptor, decreased ethylene production and resulted in high transcript abundance. The literature indicates two kinds of ethylene receptor genes with regard to the effects of ethylene. One group shows ethylene-induced down-regulated transcription, while the other has ethylene-induced up-regulation. The present gene is an example of the first group. The 5' flanking region showed binding sites for Myb and myb-like, homeodomain, MADS domain, NAC, TCP, bHLH and EIN3-like transcription factors. The binding site for the EIN3-like factor might explain the ethylene effect on transcription. A few other transcription factors (RAV1 and NAC) seem also related to ethylene effects. PMID:25590685

  4. Role of auxin in orchid development.

    PubMed

    Novak, Stacey D; Luna, Lila J; Gamage, Roshan N

    2014-01-01

    Auxin's capacity to regulate aspects of plant development has been well characterized in model plant systems. In contrast, orchids have received considerably less attention, but the realization that many orchid species are endangered has led to culture-based propagation studies which have unveiled some functions for auxin in this system. This mini-review summarizes the many auxin-mediated developmental responses in orchids that are consistent with model systems; however, it also brings to the forefront auxin responses that are unique to orchid development, namely protocorm formation and ovary/ovule maturation. With regard to shoot establishment, we also assess auxin's involvement in orchid germination, PLB formation, and somatic embryogenesis. Further, it makes evident that auxin flow during germination of the undifferentiated, but mature, orchid embryo mirrors late embryogenesis of typical angiosperms. Also discussed is the use of orchid protocorms in future phytohormone studies to better understand the mechanisms behind meristem formation and organogenesis. PMID:25482818

  5. Role of Auxin in orchid development.

    PubMed

    Darling-Novak, Stacey; Luna, Lila J; Gamage, Roshan N

    2014-08-25

    Auxin's capacity to regulate aspects of plant development has been well characterized in model plant systems. In contrast, orchids have received considerably less attention, but the realization that many orchid species are endangered has led to culture-based propagation studies which have unveiled some functions for auxin in this system. This mini-review summarizes the many auxin-mediated developmental responses in orchids that are consistent with model systems; however, it also brings to the forefront auxin responses that are unique to orchid development, namely protocorm formation and ovary/ovule maturation. With regard to shoot establishment, we also assess auxin's involvement in orchid germination, PLB formation, and somatic embryogenesis. Further, it makes evident that auxin flow during germination of the undifferentiated, but mature, orchid embryo mirrors late embryogenesis of typical angiosperms. Also discussed is the use of orchid protocorms in future phytohormone studies to better understand the mechanisms behind meristem formation and organogenesis. PMID:25153202

  6. Role of Auxin in Orchid Development

    PubMed Central

    Novak, Stacey D.; Luna, Lila J.; Gamage, Roshan N.

    2014-01-01

    Auxin's capacity to regulate aspects of plant development has been well characterized in model plant systems. In contrast, orchids have received considerably less attention, but the realization that many orchid species are endangered has led to culture-based propagation studies which have unveiled some functions for auxin in this system. This mini-review summarizes the many auxin-mediated developmental responses in orchids that are consistent with model systems; however, it also brings to the forefront auxin responses that are unique to orchid development, namely protocorm formation and ovary/ovule maturation. With regard to shoot establishment, we also assess auxin's involvement in orchid germination, PLB formation, and somatic embryogenesis. Further, it makes evident that auxin flow during germination of the undifferentiated, but mature, orchid embryo mirrors late embryogenesis of typical angiosperms. Also discussed is the use of orchid protocorms in future phytohormone studies to better understand the mechanisms behind meristem formation and organogenesis. PMID:25482818

  7. Two novel bibenzyls from Dendrobium trigonopus.

    PubMed

    Hu, Jiang-Miao; Chen, Ji-Jun; Yu, Hong; Zhao, You-Xing; Zhou, Jun

    2008-01-01

    Two novel bibenzyl trigonopols A (1) and B (2), together with seven known compounds, gigantol (3), tristin (4), moscatin (5), hircinol (6), naringenin (7), 3-(4-hydroxy-3-methoxyphenyl)-2-propen-1-ol (8), and ( - )-syringaresinol (9), have been isolated from the stems of Dendrobium trigonopus, of which compounds 6, 8, and 9 were isolated for the first time from this species. The structures of two new compounds were elucidated as threo-22-(17-hydroxyl-9-(3-hydroxyl-4-methoxy-phenethyl)-13,16,18-trimethoxy-21H-benzo[c]chromen-21-yl)ethane-22, 23-diol (1) and 9-(4-hydroxyl-3-methoxy-phenethyl)-17-(21-hydroxyl-20-methoxy-phenyl)chroman-11, 16-diol (2) on the basis of spectroscopic methods. Trigonopol A was found to exhibit antiplatelet aggregation activity in vitro with 67.55% inhibitory ration at 1.4337 x 10(- 3) M. PMID:18636377

  8. Five new compounds from Dendrobium longicornu.

    PubMed

    Hu, Jiang-Miao; Chen, Ji-Jun; Yu, Hong; Zhao, You-Xing; Zhou, Jun

    2008-04-01

    A novel bibenzyl, a new bibenzyl, two new phenanthrenes, and a new lignin glycoside, namely longicornuol A (1), 4-[2-(3-hdroxyphenol)-1-methoxyethyl]-2,6-dimethoxyphenol (2), 5-hydroxy-7-methoxy-9,10-dihydrophenanthrene-1,4-dione (3), 7-methoxy-9,10-dihydrophenanthrene-2,4,5-triol (4) and erythro-1-(4-O-beta-D-glucopyranosyl-3-methoxyphenyl)-2-[4-(3-hydroxypropyl)-2,6-dimethoxyphenoxy]-1,3-propanediol ( 5), together with 14 known compounds, were isolated from the stems of Dendrobium longicornu. All structures were elucidated by spectroscopic methods (NMR, MS, UV and IR). Anti-platelet aggregation activities of compounds 1 - 5 were also tested. PMID:18543150

  9. Three new bibenzyl derivatives from Dendrobium candidum.

    PubMed

    Li, Yan; Wang, Chun-Lan; Wang, Ya-Jun; Guo, Shun-Xing; Yang, Jun-Shan; Chen, Xiao-Mei; Xiao, Pei-Gen

    2009-02-01

    Three new compounds were isolated from the stems of Dendrobium candidum: (S)-3,4,4'-trihydroxy-5,alpha-dimethoxybibenzyl (1), named dendrocandin C; (S)-3,4,4'-trihydroxy-5-methoxy-alpha-ethoxybibenzyl (2), named dendrocandin D; and 3,3',4,4'-tetrahydroxy-5-methoxybibenzyl (3), named dendrocandin E. Their structures were elucidated by 1D- and 2D-NMR spectroscopy and mass spectroscopy. The isolated compounds exhibited potent antioxidant activity in the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging test, with IC(50) values of 34.2, 34.5, and 15.6 microM for compounds 1, 2, and 3, respectively. Vitamin C was used as positive control with IC(50) 23.2 microM. PMID:19182417

  10. Five new phenolic compounds from Dendrobium aphyllum.

    PubMed

    Yang, Dan; Liu, Liang-Yan; Cheng, Zhong-Quan; Xu, Feng-Qing; Fan, Wei-Wei; Zi, Cheng-Ting; Dong, Fa-Wu; Zhou, Jun; Ding, Zhong-Tao; Hu, Jiang-Miao

    2015-01-01

    One new phenanthrene, aphyllone A (1) and four new bibenzyl derivatives, aphyllone B (2) and aphyllals C-D (3-5), together with nine known compounds (6-14), were isolated from the stems of Dendrobium aphyllum (Roxb.) C. E. Fischer. The structures of these new compounds were elucidated by means of extensive spectroscopic analyses, and the absolute configuration of compound 1 was determined by single crystal X-ray diffraction and quantum calculations. Compounds 6, 8 and 14 inhibited NO production at the concentration of 25 μM in LPS-stimulated RAW264.7 cells with the inhibition (%) of 32.48, 35.68, and 38.50. Compound 2 possessed significant DPPH radical scavenging activity with scavenging percentage of 87.97% at the concentration of 100 μg/mL. PMID:25447160

  11. [Some worries about Dendrobium officinale industry].

    PubMed

    Li, Guang; Lu, Juan; Chen, Xi

    2013-02-01

    In recent years, with the continuous development of the industry of Dendrobium officinale, the technological alliance on CEEUSRO has been established. However, many problems also exposed with the rapid expansion of the industry, such as weak basic research, single species of the product, lack of in-depth studies and difficult to guarantee the quality. Industrial foam was gradually formed. To guard against the D. officinale becoming another "Puer Tea" , the authors believe that the key to sustainable development of the industry is enterprises and research institutes should strengthen basic research, speed up development of application of integrated innovations, government should strengthen guidance, regulate the operation of the market, then protect the quality of D. officinale in the market. PMID:23713266

  12. [Progress and countermeasures of Dendrobium officinale breeding].

    PubMed

    Si, Jin-Ping; He, Bo-wei; Yu, Qiao-xian

    2013-02-01

    The standandized cultivation of Chinese medicinal materials is based on variety. With the rapid development of Dendrobium officinale industry and increasing demand of improved varieties, many studies have concentrated on the variety breeding of D. officinale and subsequently achieved remarkable success. This paper systematically expounds the research progress of D. officinale breeding, e. g. the collection and differentiated evaluation for germplasm, theory and practice for variety breeding, tissue culture and efficient production with low-carbon for germchit, and DNA molecular marker-assisted breeding, and then indicates the main problems of the current breeding of D. officinale. Furthermore, the priorities and keys for the further breeding of D. officinale have been pointed out. PMID:23713267

  13. Further advances in orchid mycorrhizal research.

    PubMed

    Dearnaley, John D W

    2007-09-01

    Orchid mycorrhizas are mutualistic interactions between fungi and members of the Orchidaceae, the world's largest plant family. The majority of the world's orchids are photosynthetic, a small number of species are myco-heterotrophic throughout their lifetime, and recent research indicates a third mode (mixotrophy) whereby green orchids supplement their photosynthetically fixed carbon with carbon derived from their mycorrhizal fungus. Molecular identification studies of orchid-associated fungi indicate a wide range of fungi might be orchid mycobionts, show common fungal taxa across the globe and support the view that some orchids have specific fungal interactions. Confirmation of mycorrhizal status requires isolation of the fungi and restoration of functional mycorrhizas. New methods may now be used to store orchid-associated fungi and store and germinate seed, leading to more efficient culture of orchid species. However, many orchid mycorrhizas must be synthesised before conservation of these associations can be attempted in the field. Further gene expression studies of orchid mycorrhizas are needed to better understand the establishment and maintenance of the interaction. These data will add to efforts to conserve this diverse and valuable association. PMID:17582535

  14. Orchid conservation: making the links.

    PubMed

    Fay, Michael F; Pailler, Thierry; Dixon, Kingsley W

    2015-09-01

    Orchidaceae, one of the largest families of flowering plants, present particular challenges for conservation, due in great part to their often complex interactions with mycorrhizal fungi, pollinators and host trees. In this Highlight, we present seven papers focusing on orchids and their interactions and other factors relating to their conservation. PMID:26311710

  15. An orchid bee naturalizes in Florida; implications for orchids and other plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An orchid bee, Euglossa viridissima, from Mexico and Central America was detected in southern Florida in 2003 and now has become locally abundant. Orchid bees are important pollinators of diverse plants in their native tropical America which suggests that the naturalized orchid bee could become an i...

  16. The complete chloroplast genome of the Dendrobium strongylanthum (Orchidaceae: Epidendroideae).

    PubMed

    Li, Jing; Chen, Chen; Wang, Zhe-Zhi

    2016-07-01

    Complete chloroplast genome sequence is very useful for studying the phylogenetic and evolution of species. In this study, the complete chloroplast genome of Dendrobium strongylanthum was constructed from whole-genome Illumina sequencing data. The chloroplast genome is 153 058 bp in length with 37.6% GC content and consists of two inverted repeats (IRs) of 26 316 bp. The IR regions are separated by large single-copy region (LSC, 85 836 bp) and small single-copy (SSC, 14 590 bp) region. A total of 130 chloroplast genes were successfully annotated, including 84 protein coding genes, 38 tRNA genes, and eight rRNA genes. Phylogenetic analyses showed that the chloroplast genome of Dendrobium strongylanthum is related to that of the Dendrobium officinal. PMID:26153739

  17. Gigantol, a bibenzyl from Dendrobium draconis, inhibits the migratory behavior of non-small cell lung cancer cells.

    PubMed

    Charoenrungruang, Sopanya; Chanvorachote, Pithi; Sritularak, Boonchoo; Pongrakhananon, Varisa

    2014-06-27

    Lung cancer is one of the most common causes of cancer death due to its high metastasis potential. The process of cancer migration is an early step that is required for successful metastasis. The discovery and development of natural compounds for cancer therapy have garnered increasing attention in recent years. Gigantol (1) is a bibenzyl compound derived from the Thai orchid, Dendrobium draconis. It exhibits significant cytotoxic activity against several cancer cell lines; however, until recently, the role of 1 on tumor metastasis has not been characterized. This study demonstrates that 1 suppresses the migratory behavior of non-small cell lung cancer H460 cells. Western blot analysis reveals that 1 down-regulates caveolin-1 (Cav-1), activates ATP-dependent tyrosine kinase (phosphorylated Akt at Ser 473), and cell division cycle 42 (Cdc42), thereby suppressing filopodia formation. The inhibitory effect of 1 on cell movement is also exhibited in another lung cancer cell line, H292, but not in normal human keratinocytes (HaCat). The inhibitory activity of 1 on lung cancer migration suggests that this compound may be suitable for further development for the treatment of cancer metastasis. PMID:24844664

  18. Comparison of photosynthesis and fluorescent parameters between Dendrobium officinale and Dendrobium loddigesii

    PubMed Central

    Sun, Zhi-Rong; Zhu, Nan-Nan; Cheng, Li-Li; Yang, Chun-Ning

    2015-01-01

    Objective: To investigate the photosynthesis and fluorescent parameters between Dendrobium officinale and Dendrobium loddigesii, based on which to provide helpful information for the artificial cultivation of these cultivars. Methods: Seeds were placed on the MS medium supplemented with 0.2 mg/L NAA, 2% (w/v) sucrose, 15% (v/v) potato extracts and powered agar (pH 5.8). Two months after germination, seedlings (n = 10) were transferred onto rooting medium containing MS medium supplemented with 0.5 mg/L NAA, 3% (w/v) sucrose, 20% (v/v) potato extracts and 1‰ (w/v) activated carbon (pH 5.8) in a glass bottle (6.5 cm in diameter and 9.5 cm in height) with a white transparent plastic cap. Chlorophyll content was determined using the UV-Vis spectrophotometric method. In addition, rates of oxygen evolution and uptake were measured. The chlorophyll fluorescence was determined at room temperature using PAM 2000 chlorophyll fluorometer (Heinz Walz GmbH, Germany). Results: From month 5 to month 10, the overall contents of both chlorophyll a and chlorophyll b were higher in D. loddigesii compared with those in D. officinale. No statistical differences were observed in the apparent photosynthetic rate (APR) between D. loddigesii and D. officinale. No statistical difference was noticed in the Fo, Fm and Fv between D. loddigesii and D. officinale (P > 0.05). Significant increase was noticed in the oxygen consuming in PSI in month-8 and month-10 compared with that of month-6 in D. loddigesii. Nevertheless, in the D. officinale, the oxygen consuming in PSI in month-6 was remarkably increased with those of month-8 and month-10, respectively. Conclusions: The photosynthesis and fluorescence parameters varied in the seedling of D. loddigesii and D. officinale. Such information could contribute to the artificial cultivation of these cultivars. PMID:26550239

  19. Orchid pollination by sexual deception: pollinator perspectives.

    PubMed

    Gaskett, A C

    2011-02-01

    The extraordinary taxonomic and morphological diversity of orchids is accompanied by a remarkable range of pollinators and pollination systems. Sexually deceptive orchids are adapted to attract specific male insects that are fooled into attempting to mate with orchid flowers and inadvertently acting as pollinators. This review summarises current knowledge, explores new hypotheses in the literature, and introduces some new approaches to understanding sexual deception from the perspective of the duped pollinator. Four main topics are addressed: (1) global patterns in sexual deception, (2) pollinator identities, mating systems and behaviours, (3) pollinator perception of orchid deceptive signals, and (4) the evolutionary implications of pollinator responses to orchid deception, including potential costs imposed on pollinators by orchids. A global list of known and putative sexually deceptive orchids and their pollinators is provided and methods for incorporating pollinator perspectives into sexual deception research are provided and reviewed. At present, almost all known sexually deceptive orchid taxa are from Australia or Europe. A few sexually deceptive species and genera are reported for New Zealand and South Africa. In Central and Southern America, Asia, and the Pacific many more species are likely to be identified in the future. Despite the great diversity of sexually deceptive orchid genera in Australia, pollination rates reported in the literature are similar between Australian and European species. The typical pollinator of a sexually deceptive orchid is a male insect of a species that is polygynous, monandrous, haplodiploid, and solitary rather than social. Insect behaviours involved in the pollination of sexually deceptive orchids include pre-copulatory gripping of flowers, brief entrapment, mating, and very rarely, ejaculation. Pollinator behaviour varies within and among pollinator species. Deception involving orchid mimicry of insect scent signals is

  20. Frozen beauty: The cryobiotechnology of orchid diversity.

    PubMed

    Popova, Elena; Kim, Haeng Hoon; Saxena, Praveen Kumar; Engelmann, Florent; Pritchard, Hugh W

    2016-01-01

    Orchids (Orchidaceae) are one of the most diverse plant groups on the planet with over 25,000 species. For over a century, scientists and horticulturalists have been fascinated by their complex floral morphology, pollinator specificity and multiple ethnobotanical uses, including as food, flavourings, medicines, ornaments, and perfumes. These important traits have stimulated world-wide collection of orchid species, often for the commercial production of hybrids and leading to frequent overexploitation. Increasing human activities and global environmental changes are also accelerating the threat of orchid extinction in their natural habitats. In order to improve gene conservation strategies for these unique species, innovative developments of cryopreservation methodologies are urgently needed based on an appreciation of low temperature (cryo) stress tolerance, the stimulation of recovery growth of plant tissues in vitro and on the 'omics' characterization of the targeted cell system (biotechnology). The successful development and application of such cryobiotechnology now extends to nearly 100 species and commercial hybrids of orchids, underpinning future breeding and species conservation programmes. In this contribution, we provide an overview of the progress in cryobanking of a range of orchid tissues, including seeds, pollen, protocorms, protocorm-like bodies, apices excised from in vitro plants, cell suspensions, rhizomes and orchid fungal symbionts. We also highlight future research needs. PMID:26792590

  1. Rapid authentication of different ages of tissue-cultured and wild Dendrobium huoshanense as well as wild Dendrobium henanense using FTIR and 2D-COS IR

    NASA Astrophysics Data System (ADS)

    Chen, Nai-Dong; Chen, Nai-Fu; Li, Jun; Cao, Cai-Yun; Wang, Jin-Mei

    2015-12-01

    The accumulating of pharmaceutical chemicals in medicinal plants would greatly be affected by their ages and establishing a fast quality-identification method to evaluate the similarity of medicinal herbs at different cultivated ages is a critical step for assurance of quality and safety in the TCM industry. In this work, tri-step IR macro-fingerprinting and 2D-COS IR spectrum techniques combined with statistical pattern recognition were applied for discrimination and similarity evaluation of different ages of tissue-cultured and wild Dendrobium huoshanense C. Z. Tang et S. J. Cheng as well as Dendrobium henanense J.L.Lu et L.X Gao. Both tissue-cultured and wild D. huoshanense were easily differentiated from D. henanense by FTIR and SD-IR spectra, while it's quite difficult to discriminate different cultivated years of the three investigated Dendrobiums. In 2D-COS IR spectra, 1-5 auto-peaks with different indensity and positions were located in the region 1160-1030 cm-1 of the twelve Dendrobium samples and thus could be used to identify Dendrobium samples at different ages. Principle component analysis (PCA) of synchronous 2D-COS data showed that the twelve samples were effectively identified and evaluated. The results indicated that the tri-step infrared macro-fingerprinting combined with PCA method was suitable to differentiate the cultivated ages of Dendrobiums with species and orgins rapidly and nondestructively.

  2. Colour mimicry and sexual deception by Tongue orchids (Cryptostylis).

    PubMed

    Gaskett, A C; Herberstein, M E

    2010-01-01

    Typically, floral colour attracts pollinators by advertising rewards such as nectar, but how does colour function when pollinators are deceived, unrewarded, and may even suffer fitness costs? Sexually deceptive orchids are pollinated only by male insects fooled into mating with orchid flowers and inadvertently transferring orchid pollinia. Over long distances, sexually deceptive orchids lure pollinators with counterfeit insect sex pheromones, but close-range deception with colour mimicry is a tantalising possibility. Here, for the first time, we analyse the colours of four sexually deceptive Cryptostylis orchid species and the female wasp they mimic (Lissopimpla excelsa, Ichneumonidae), from the perspective of the orchids' single, shared pollinator, male Lissopimpla excelsa. Despite appearing different to humans, the colours of the orchids and female wasps were effectively identical when mapped into a hymenopteran hexagonal colour space. The orchids and wasps reflected predominantly red-orange wavelengths, but UV was also reflected by raised bumps on two orchid species and by female wasp wings. The orchids' bright yellow pollinia contrasted significantly with their overall red colour. Orchid deception may therefore involve accurate and species-specific mimicry of wavelengths reflected by female wasps, and potentially, exploitation of insects' innate attraction to UV and yellow wavelengths. In general, mimicry may be facilitated by exploiting visual vulnerabilities and evolve more readily at the peripheries of sensory perception. Many sexually deceptive orchids are predominantly red, green or white: colours that are all potentially difficult for hymenoptera to detect or distinguish from the background. PMID:19798479

  3. Linnaean sources and concepts of orchids

    PubMed Central

    Jarvis, Charlie; Cribb, Phillip

    2009-01-01

    Background Linnaeus developed a robust system for naming plants and a useful, if mechanical, system for classifying them. His binomial nomenclature proved the catalyst for the rapid development of our knowledge of orchids, with his work on the family dating back to 1737 in the first edition of his Genera Plantarum. His first work devoted to orchids, indeed the first monograph of the family, was published in 1740 and formed the basis for his account in Species Plantarum, published in 1753, in which he gave a binomial name to each species. Given the overwhelming number of orchids, he included surprisingly few – only 62 mostly European species – in Species Plantarum, his seminal work on the plants of the world. This reflects the European origin of modern botany and the concentration of extra-European exploration on other matters, such as conquest, gold and useful plants. Nevertheless, the scope of Linnaeus' work is broad, including plants from as far afield as India, Japan, China and the Philippines to the east, and eastern Canada, the West Indies and northern South America to the west. In his later publications he described and named a further 45 orchids, mostly from Europe, South Africa and the tropical Americas. Scope The philosophical basis of Linnaeus' work on orchids is discussed and his contribution to our knowledge of the family assessed. His generic and species concepts are considered in the light of current systematic ideas, but his adoption of binomial nomenclature for all plants is his lasting legacy. PMID:19182221

  4. General unknown screening, antioxidant and anti-inflammatory potential of Dendrobium macrostachyum Lindl.

    PubMed Central

    Sukumaran, Nimisha Pulikkal; Yadav, R. Hiranmai

    2016-01-01

    Context: D. macrostachyum is an epiphytic orchid abundant in Southern India and is reported for pain relief in folklore. Aims: The objective of the present study was to determine in vitro free radical scavenging and anti-inflammatory activity of D. macrostachyum and to perform LCMS based metabolic profiling of the plant. Settings and Design: Sequential stem and leaf extracts were assessed for its antioxidant and anti-inflammatory activity by in vitro methods. Materials and Methods: The antioxidant activity determined by assays based on the decolourization of the radical monocation of DPPH, ABTS and reducing power. Total amount of phenolics for quantitative analysis of antioxidative components was estimated. In vitro anti-inflammatory activity was evaluated using protein denaturation assay, membrane stabilization assay and proteinase inhibitory activity. Methanolic extract of plant was subjected to LCMS. Results: The stem ethanolic extracts exhibited significant IC50 value of 10.21, 31.54 and 142.97 μg/ml respectively for DPPH, ABTS radical scavenging and reducing power activity. The ethanol and water extract was highly effective as albumin denaturation inhibitors (IC50 = 114.13 and 135.818 μg/ml respectively) and proteinase inhibitors (IC50 = 72.49 and 129.681 μg/ml respectively). Membrane stabilization was also noticeably inhibited by the stem ethanolic extract among other extracts (IC50 = 89.33 μg/ml) but comparatively lower to aspirin standard (IC50 = 83.926 μg/ml). The highest total phenol content was exhibited by ethanolic stem and leaf extracts respectively at 20 and 16 mg of gallic acid equivalents of dry extract. On LCMS analysis 20 constituents were identified and it included chemotaxonomic marker for Dendrobium species. Conclusions: The results showed a relatively high concentration of phenolics, high scavenger activity and high anti-inflammatory activity of the stem extract compared to the leaf extract. The results indicate that the plant can be a

  5. Darwin teleologist? Design in The orchids.

    PubMed

    Hoquet, Thierry

    2010-02-01

    Focusing on "The Orchids," this article aims at disentangling the concepts of teleology, design and natural theology. It refers to several contemporary critics of Darwin (Kölliker, Argyll, Royer, Candolle, Delpino) to challenge Huxley's interpretation that Darwin's system was "a deathblow" to teleology. "The Orchids" seems rather to be a "flank-movement" (Gray): it departs from the Romantic theories of transmutation and the "imaginary examples" of the Origin; it focuses on empirical data and on teleological structures. Although Darwin refers to natural selection, his readers mock him for his fascination for delicate morphological contrivances and co-adaptations - a sign that he was inescapably lured to finality. Some even suggested that his system was a "theodicy". In the history of Darwinism, "The Orchids" reveals "another" quite unexpected and heterodox Darwin: freed from the hypothetical fancies of the Origin, and even suggesting a new kind of physico-theology. PMID:20338528

  6. Orchidstra: an integrated orchid functional genomics database.

    PubMed

    Su, Chun-lin; Chao, Ya-Ting; Yen, Shao-Hua; Chen, Chun-Yi; Chen, Wan-Chieh; Chang, Yao-Chien Alex; Shih, Ming-Che

    2013-02-01

    A specialized orchid database, named Orchidstra (URL: http://orchidstra.abrc.sinica.edu.tw), has been constructed to collect, annotate and share genomic information for orchid functional genomics studies. The Orchidaceae is a large family of Angiosperms that exhibits extraordinary biodiversity in terms of both the number of species and their distribution worldwide. Orchids exhibit many unique biological features; however, investigation of these traits is currently constrained due to the limited availability of genomic information. Transcriptome information for five orchid species and one commercial hybrid has been included in the Orchidstra database. Altogether, these comprise >380,000 non-redundant orchid transcript sequences, of which >110,000 are protein-coding genes. Sequences from the transcriptome shotgun assembly (TSA) were obtained either from output reads from next-generation sequencing technologies assembled into contigs, or from conventional cDNA library approaches. An annotation pipeline using Gene Ontology, KEGG and Pfam was built to assign gene descriptions and functional annotation to protein-coding genes. Deep sequencing of small RNA was also performed for Phalaenopsis aphrodite to search for microRNAs (miRNAs), extending the information archived for this species to miRNA annotation, precursors and putative target genes. The P. aphrodite transcriptome information was further used to design probes for an oligonucleotide microarray, and expression profiling analysis was carried out. The intensities of hybridized probes derived from microarray assays of various tissues were incorporated into the database as part of the functional evidence. In the future, the content of the Orchidstra database will be expanded with transcriptome data and genomic information from more orchid species. PMID:23324169

  7. Cytotoxic and Antimigratory Activities of Phenolic Compounds from Dendrobium brymerianum

    PubMed Central

    Klongkumnuankarn, Pornprom; Busaranon, Kesarin; Chanvorachote, Pithi; Sritularak, Boonchoo; Jongbunprasert, Vichien; Likhitwitayawuid, Kittisak

    2015-01-01

    Chromatographic separation of a methanol extract prepared from the whole plant of Dendrobium brymerianum led to the isolation of eight phenolic compounds. Among the isolated compounds (1–8), moscatilin (1), gigantol (3), lusianthridin (4), and dendroflorin (6) showed appreciable cytotoxicity against human lung cancer cell lines with IC50 values of 196.7, 23.4, 65.0, and 125.8 μg/mL, respectively, and exhibited antimigratory property at nontoxic concentrations. This study is the first report on the biological activities of this plant. PMID:25685168

  8. The complete chloroplast genome sequence of Dendrobium officinale.

    PubMed

    Yang, Pei; Zhou, Hong; Qian, Jun; Xu, Haibin; Shao, Qingsong; Li, Yonghua; Yao, Hui

    2016-01-01

    The complete chloroplast sequence of Dendrobium officinale, an endangered and economically important traditional Chinese medicine, was reported and characterized. The genome size is 152,018 bp, with 37.5% GC content. A pair of inverted repeats (IRs) of 26,284 bp are separated by a large single-copy region (LSC, 84,944 bp) and a small single-copy region (SSC, 14,506 bp). The complete cp DNA contains 83 protein-coding genes, 39 tRNA genes and 8 rRNA genes. Fourteen genes contained one or two introns. PMID:25103425

  9. [Molecular characterization of a HMG-CoA reductase gene from a rare and endangered medicinal plant, Dendrobium officinale].

    PubMed

    Zhang, Lin; Wang, Ji-Tao; Zhang, Da-Wei; Zhang, Gang; Guo, Shun-Xing

    2014-03-01

    The 3-hydroxy-3-methylglutaryl-CoA reductase (HMGR) catalyzes the conversion of HMG-CoA to mevalonate in mavalonic acid pathway, which is the first committed step for isoprenoid biosynthesis in plants. However, it still remains unclear whether HGMR gene plays a role in the isoprenoid biosynthesis in Dendrobium officinale, an endangered epiphytic orchid species. In the present study, a HMGR encoding gene, designed as DoHMGR1 (GenBank accession JX272632), was identified from D. officinale using the reverse transcription polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends (RACE) methods, for the first time. The full length cDNA of DoHMGR1 was 2 071 bp in length and encoded a 562-aa protein with a molecular weight of 59.73 kD and an isoelectric point (pI) of 6.18. The deduced DoHMGR1 protein, like other HMGR proteins, constituted four conserved domains (63-561, 147-551, 268-383 and 124-541) and two transmembrane motifs (42-64 and 85-107). Multiple sequence alignment and phylogenetic analyses demonstrated that DoHMGR1 had high identity (67%-89%) to a number of HMGR genes from various plants and was closely related to Vanda hybrid cultivar, rice and maize monocots. Real time quantitative PCR (qPCR) analysis revealed that DoHMGR1 was expressed in the three included organs. The transcripts were the most abundant in the roots with 2.13 fold over that in the leaves, followed by that in the stems with 1.98 fold. Molecular characterization of DoHMGR1 will be useful for further functional elucidation of the gene involving in isoprenoid biosynthesis pathway in D. officinale. PMID:24961116

  10. Similarity Evaluation of Different Origins and Species of Dendrobiums by GC-MS and FTIR Analysis of Polysaccharides

    PubMed Central

    Chen, Nai-Dong; Chen, Nai-Fu; Li, Jun; Cao, Cai-Yun; Wang, Jin-Mei; Huang, He-Ping

    2015-01-01

    GC-MS method combined with FTIR techniques by the analysis of polysaccharide was applied to evaluate the similarity between wild (W) and tissue-cultured (TC) Dendrobium huoshanense (DHS), Dendrobium officinale (DO), and Dendrobium moniliforme (DM) as well as 3 wild Dendrobium spp.: Dendrobium henanense (DHN), Dendrobium loddigesii (DL), and Dendrobium crepidatum (DC). Eight monosaccharides involving xylose, arabinose, rhamnose, glucose, mannose, fructose, galactose, and galacturonic acid were identified in the polysaccharide from each Dendrobium sample while the contents of the monosugars varied remarkably across origins and species. Further similarity evaluation based on GC-MS data showed that the rcor values of different origins of DHS, DO, and DM were 0.831, 0.865, and 0.884, respectively, while the rcor values ranged from 0.475 to 0.837 across species. FTIR files of the polysaccharides revealed that the similarity coefficients between W and TC-DHS, DO, and DM were 88.7%, 86.8%, and 88.5%, respectively, in contrast to the similarity coefficients varying from 57.4% to 82.6% across species. These results suggested that the structures of polysaccharides between different origins of the investigated Dendrobiums might be higher than what we had supposed. PMID:26539215

  11. Molecular Identification of Dendrobium Species (Orchidaceae) Based on the DNA Barcode ITS2 Region and Its Application for Phylogenetic Study

    PubMed Central

    Feng, Shangguo; Jiang, Yan; Wang, Shang; Jiang, Mengying; Chen, Zhe; Ying, Qicai; Wang, Huizhong

    2015-01-01

    The over-collection and habitat destruction of natural Dendrobium populations for their commercial medicinal value has led to these plants being under severe threat of extinction. In addition, many Dendrobium plants are similarly shaped and easily confused during the absence of flowering stages. In the present study, we examined the application of the ITS2 region in barcoding and phylogenetic analyses of Dendrobium species (Orchidaceae). For barcoding, ITS2 regions of 43 samples in Dendrobium were amplified. In combination with sequences from GenBank, the sequences were aligned using Clustal W and genetic distances were computed using MEGA V5.1. The success rate of PCR amplification and sequencing was 100%. There was a significant divergence between the inter- and intra-specific genetic distances of ITS2 regions, while the presence of a barcoding gap was obvious. Based on the BLAST1, nearest distance and TaxonGAP methods, our results showed that the ITS2 regions could successfully identify the species of most Dendrobium samples examined; Second, we used ITS2 as a DNA marker to infer phylogenetic relationships of 64 Dendrobium species. The results showed that cluster analysis using the ITS2 region mainly supported the relationship between the species of Dendrobium established by traditional morphological methods and many previous molecular analyses. To sum up, the ITS2 region can not only be used as an efficient barcode to identify Dendrobium species, but also has the potential to contribute to the phylogenetic analysis of the genus Dendrobium. PMID:26378526

  12. Molecular Identification of Dendrobium Species (Orchidaceae) Based on the DNA Barcode ITS2 Region and Its Application for Phylogenetic Study.

    PubMed

    Feng, Shangguo; Jiang, Yan; Wang, Shang; Jiang, Mengying; Chen, Zhe; Ying, Qicai; Wang, Huizhong

    2015-01-01

    The over-collection and habitat destruction of natural Dendrobium populations for their commercial medicinal value has led to these plants being under severe threat of extinction. In addition, many Dendrobium plants are similarly shaped and easily confused during the absence of flowering stages. In the present study, we examined the application of the ITS2 region in barcoding and phylogenetic analyses of Dendrobium species (Orchidaceae). For barcoding, ITS2 regions of 43 samples in Dendrobium were amplified. In combination with sequences from GenBank, the sequences were aligned using Clustal W and genetic distances were computed using MEGA V5.1. The success rate of PCR amplification and sequencing was 100%. There was a significant divergence between the inter- and intra-specific genetic distances of ITS2 regions, while the presence of a barcoding gap was obvious. Based on the BLAST1, nearest distance and TaxonGAP methods, our results showed that the ITS2 regions could successfully identify the species of most Dendrobium samples examined; Second, we used ITS2 as a DNA marker to infer phylogenetic relationships of 64 Dendrobium species. The results showed that cluster analysis using the ITS2 region mainly supported the relationship between the species of Dendrobium established by traditional morphological methods and many previous molecular analyses. To sum up, the ITS2 region can not only be used as an efficient barcode to identify Dendrobium species, but also has the potential to contribute to the phylogenetic analysis of the genus Dendrobium. PMID:26378526

  13. Evaluation of Chemical Constituents and Important Mechanism of Pharmacological Biology in Dendrobium Plants

    PubMed Central

    Lam, Yau; Ng, Tzi Bun; Yao, Ren Ming; Shi, Jun; Xu, Kai; Sze, Stephen Cho Wing; Zhang, Kalin Yanbo

    2015-01-01

    Dendrobium species, commonly known as “Shihu” or “Huangcao,” represents the second largest genus of Orchidaceae, which are used commonly as tonic herbs and healthy food in many Asian countries. The aim of this paper is to review the history, chemistry, and pharmacology of different Dendrobium species on the basis of the latest academic literatures found in Google Scholar, PubMed, Sciencedirect, Scopus, and SID. PMID:25945114

  14. Colour mimicry and sexual deception by Tongue orchids ( Cryptostylis)

    NASA Astrophysics Data System (ADS)

    Gaskett, A. C.; Herberstein, M. E.

    2010-01-01

    Typically, floral colour attracts pollinators by advertising rewards such as nectar, but how does colour function when pollinators are deceived, unrewarded, and may even suffer fitness costs? Sexually deceptive orchids are pollinated only by male insects fooled into mating with orchid flowers and inadvertently transferring orchid pollinia. Over long distances, sexually deceptive orchids lure pollinators with counterfeit insect sex pheromones, but close-range deception with colour mimicry is a tantalising possibility. Here, for the first time, we analyse the colours of four sexually deceptive Cryptostylis orchid species and the female wasp they mimic ( Lissopimpla excelsa, Ichneumonidae), from the perspective of the orchids’ single, shared pollinator, male Lissopimpla excelsa. Despite appearing different to humans, the colours of the orchids and female wasps were effectively identical when mapped into a hymenopteran hexagonal colour space. The orchids and wasps reflected predominantly red-orange wavelengths, but UV was also reflected by raised bumps on two orchid species and by female wasp wings. The orchids’ bright yellow pollinia contrasted significantly with their overall red colour. Orchid deception may therefore involve accurate and species-specific mimicry of wavelengths reflected by female wasps, and potentially, exploitation of insects’ innate attraction to UV and yellow wavelengths. In general, mimicry may be facilitated by exploiting visual vulnerabilities and evolve more readily at the peripheries of sensory perception. Many sexually deceptive orchids are predominantly red, green or white: colours that are all potentially difficult for hymenoptera to detect or distinguish from the background.

  15. Collection and trade of wild-harvested orchids in Nepal

    PubMed Central

    2013-01-01

    Background Wild orchids are illegally harvested and traded in Nepal for use in local traditional medicine, horticulture, and international trade. This study aims to: 1) identify the diversity of species of wild orchids in trade in Nepal; 2) study the chain of commercialization from collector to client and/or export; 3) map traditional knowledge and medicinal use of orchids; and 4) integrate the collected data to propose a more sustainable approach to orchid conservation in Nepal. Methods Trade, species diversity, and traditional use of wild-harvested orchids were documented during field surveys of markets and through interviews. Trade volumes and approximate income were estimated based on surveys and current market prices. Orchid material samples were identified to species level using a combination of morphology and DNA barcoding. Results Orchid trade is a long tradition, and illegal export to China, India and Hong Kong is rife. Estimates show that 9.4 tons of wild orchids were illegally traded from the study sites during 2008/2009. A total of 60 species of wild orchids were reported to be used in traditional medicinal practices to cure at least 38 different ailments, including energizers, aphrodisiacs and treatments of burnt skin, fractured or dislocated bones, headaches, fever and wounds. DNA barcoding successfully identified orchid material to species level that remained sterile after culturing. Conclusions Collection of wild orchids was found to be widespread in Nepal, but illegal trade is threatening many species in the wild. Establishment of small-scale sustainable orchid breeding enterprises could be a valuable alternative for the production of medicinal orchids for local communities. Critically endangered species should be placed on CITES Appendix I to provide extra protection to those species. DNA barcoding is an effective method for species identification and monitoring of illegal cross-border trade. PMID:24004516

  16. [Bibenzyl from Dendrobium inhibits angiogenesis and its underlying mechanism].

    PubMed

    Gong, Chen-Yuan; Lu, Bin; Yang, Li; Wang, Lei; Ji, Li-Li

    2013-03-01

    Bibenzyl is a type of active compounds abundant in Dendrobium. In the present study, we investigated the inhibitory effects of six bibenzyls isolated from Dendrobium species on vascular endothelial growth factor (VEGF)-induced tube formation in human umbilical vascular endothelial cells (HUVECs). All those bibenzyls inhibited VEGF-induced tube formation at 10 micromol x L(-1) except tristin, and of which moscatilin was found to have the strongest activity at the same concentration. The lowest effective concentration of moscatilin was 1 micromol x L(-1). Further results showed that moscatilin inhibited VEGF-induced capillary-like tube formation on HUVECs in a concentration-dependent manner. Western blotting results showed that moscatilin also inhibited VEGF-induced phosphorylation of VEGFR2 (Flk-1/KDR) and extracellular signal-regulated kinase 1/2 (ERK1/2). Further results showed that moscatilin inhibited VEGF-induced activation of c-Raf and MEK1/2, which are both upstream signals of ERK1/2. Taken together, results presented here demonstrated that moscatilin inhibited angiogenesis via blocking the activation of VEGFR2 (Flk-1/KDR) and c-Raf-MEK1/2-ERK1/2 signals. PMID:23724644

  17. Anti-inflammatory phenanthrene derivatives from stems of Dendrobium denneanum.

    PubMed

    Lin, Yuan; Wang, Fei; Yang, Li-Juan; Chun, Ze; Bao, Jin-Ku; Zhang, Guo-Lin

    2013-11-01

    Cultivated Dendrobium denneanum has been substituted for other endangered Dendrobium species in recent years, but there have been few studies regarding either its chemical constituents or pharmacological effects. In this study, three phenanthrene glycosides, three 9,10-dihydrophenanthrenes, two 9,10-dihydrophenanthrenes glycosides, and four known phenanthrene derivatives, were isolated from the stems of D. denneanum. Their structures were elucidated on the basis of MS and NMR spectroscopic data. Ten compounds were found to inhibit nitric oxide (NO) production in lipopolysaccharide (LPS)-activated mouse macrophage RAW264.7 cells with IC50 values of 0.7-41.5 μM, and exhibited no cytotoxicity in RAW264.7, HeLa, or HepG2 cells. Additionally, it was found that 2,5-dihydroxy-4-methoxy-phenanthrene 2-O-β-d-glucopyranoside, and 5-methoxy-2,4,7,9S-tetrahydroxy-9,10-dihydrophenanthrene suppressed LPS-induced expression of inducible NO synthase (iNOS) inhibited phosphorylation of p38, JNK as well as mitogen-activated protein kinase (MAPK), and inhibitory kappa B-α (IκBα). This indicated that both compounds exert anti-inflammatory effects by inhibiting MAPKs and nuclear factor κB (NF-κB) pathways. PMID:24042064

  18. A new 9,10-dihydrophenanthrene from Dendrobium moniliforme.

    PubMed

    Zhao, Ningdong; Yang, Guangyu; Zhang, Yan; Chen, Lijun; Chen, Yegao

    2016-01-01

    A new 9,10-dihydrophenanthrene,1,5-dihydroxy-3,4,7-trimethoxy-9,10-dihydrophenanthrene (1) was isolated and identified from the whole plants of Dendrobium moniliforme, as well as 24 known compounds including hircinol (2), (2R*,3S*)-3-hydroxymethyl-9-methoxy-2-(4'-hydroxy-3',5'-dimethoxyphenyl)-2,3,6,7-tetrahydro-phenanthro[4,3-b]furan-5,11-diol (3), diospyrosin (4), aloifol I (5), moscatilin (6), 3,4'-dihydroxy-3',4,5-trimethoxybibenzyl (7), gigantol (8), 3,3'-dihydroxy-4,5-dimethoxybibenzyl (9), longicornuol A (10), N-trans-cinnamoyltyramine (11), paprazine (12), N-trans-feruloyl 3'-O-methyldopamine (13), moupinamide (14), dihydroconiferyl dihydro-p-coumarate (15), dihydrosinapyl dihydro-p-coumarate (16), 3-isopropyl-5-acetoxycyclohexene-2-one-1 (17), p-hydroxybenzaldehyde (18), vanillin (19), p-hydroxyphenylpropionic acid (20), vanillic acid (21), protocatechuic acid (22), (+)-syringaresinol (23), β-sitosterol (24) and daucosterol (25). Compounds 3, 4, 13, 16, 17 and 20 were isolated from the Dendrobium genus for the first time, and compounds 2, 5, 7, 9-12, 14, 15, 18, 21 and 22 were originally obtained from D. moniliforme. PMID:26132274

  19. Controlling slugs and snails in orchids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Slugs and snails are pests of orchids, preferring tender plant tissues such as flowers and root tips. Unlike many insect pests which feed only on certain types of plants, most species of slugs and snails are generalists, feeding on green plants, algae, fungi, decaying plant matter, or decaying anima...

  20. Discrimination of the rare medicinal plant Dendrobium officinale based on naringenin, bibenzyl, and polysaccharides.

    PubMed

    Chen, Xiaomei; Wang, Fangfei; Wang, Yunqiang; Li, Xuelan; Wang, Airong; Wang, Chunlan; Guo, Shunxing

    2012-12-01

    The aim of this study was to establish a method for discriminating Dendrobium officinale from four of its close relatives Dendrobium chrysanthum, Dendrobium crystallinum, Dendrobium aphyllum and Dendrobium devonianum based on chemical composition analysis. We analyzed 62 samples of 24 Dendrobium species. High performance liquid chromatography analysis confirmed that the four low molecular weight compounds 4',5,7-trihydroxyflavanone (naringenin), 3,4-dihydroxy-4',5-dime-thoxybibenzyl (DDB-2), 3',4-dihydroxy-3,5'-dimethoxybibenzyl (gigantol), and 4,4'-dihydroxy-3,3',5-trimethoxybibenzy (moscatilin), were common in the genus. The phenol-sulfuric acid method was used to quantify polysaccharides, and the monosaccharide composition of the polysaccharides was determined by gas chromatography. Stepwise discriminant analysis was used to differentiate among the five closely related species based on the chemical composition analysis. This proved to be a simple and accurate approach for discriminating among these species. The results also showed that the polysaccharide content, the amounts of the four low molecular weight compounds, and the mannose to glucose ratio, were important factors for species discriminant. Therefore, we propose that a chemical analysis based on quantification of naringenin, bibenzyl, and polysaccharides is effective for identifying D. officinale. PMID:23233224

  1. Diversity and Taxonomy of Endophytic Xylariaceous Fungi from Medicinal Plants of Dendrobium (Orchidaceae)

    PubMed Central

    Chen, Juan; Zhang, Li-Chun; Xing, Yong-Mei; Wang, Yun-Qiang; Xing, Xiao-Ke; Zhang, Da-Wei; Liang, Han-Qiao; Guo, Shun-Xing

    2013-01-01

    Dendrobium spp. are traditional Chinese medicinal plants, and the main effective ingredients (polysaccharides and alkaloids) have pharmacologic effects on gastritis infection, cancer, and anti-aging. Previously, we confirmed endophytic xylariaceous fungi as the dominant fungi in several Dendrobium species of tropical regions from China. In the present study, the diversity, taxonomy, and distribution of culturable endophytic xylariaceous fungi associated with seven medicinal species of Dendrobium (Orchidaceae) were investigated. Among the 961 endophytes newly isolated, 217 xylariaceous fungi (morphotaxa) were identified using morphological and molecular methods. The phylogenetic tree constructed using nuclear ribosomal internal transcribed spacer (ITS), large subunit of ribosomal DNA (LSU), and beta-tubulin sequences divided these anamorphic xylariaceous isolates into at least 18 operational taxonomic units (OTUs). The diversity of the endophytic xylariaceous fungi in these seven Dendrobium species was estimated using Shannon and evenness indices, with the results indicating that the dominant Xylariaceae taxa in each Dendrobium species were greatly different, though common xylariaceous fungi were found in several Dendrobium species. These findings implied that different host plants in the same habitats exhibit a preference and selectivity for their fungal partners. Using culture-dependent approaches, these xylariaceous isolates may be important sources for the future screening of new natural products and drug discovery. PMID:23472167

  2. Identification and Characterization of Three Orchid MADS-Box Genes of the AP1/AGL9 Subfamily during Floral Transition1

    PubMed Central

    Yu, Hao; Goh, Chong Jin

    2000-01-01

    Gene expressions associated with in vitro floral transition in an orchid hybrid (Dendrobium grex Madame Thong-In) were investigated by differential display. One clone, orchid transitional growth related gene 7 (otg7), encoding a new MADS-box gene, was identified to be specifically expressed in the transitional shoot apical meristem (TSAM). Using this clone as a probe, three orchid MADS-box genes, DOMADS1, DOMADS2, and DOMADS3, were subsequently isolated from the TSAM cDNA library. Phylogenetic analyses show that DOMADS1 and DOMADS2 are new members of the AGL2 subfamily and SQUA subfamily, respectively. DOMADS3 contains the signature amino acids as with the members in the independent OSMADS1 subfamily separated from the AGL2 subfamily. All three of the DOMADS genes were expressed in the TSAM during floral transition and later in mature flowers. DOMADS1 RNA was uniformly expressed in both of the inflorescence meristem and the floral primordium and later localized in all of the floral organs. DOMADS2 showed a novel expression pattern that has not been previously characterized for any other MADS-box genes. DOMADS2 transcript was expressed early in the 6-week-old vegetative shoot apical meristem in which the obvious morphological change to floral development had yet to occur. It was expressed throughout the process of floral transition and later in the columns of mature flowers. The onset of DOMADS3 transcription was in the early TSAM at the stage before the differentiation of the first flower primordium. Later, DOMADS3 transcript was only detectable in the pedicel tissues. Our results suggest that the DOMADS genes play important roles in the process of floral transition. PMID:10938351

  3. Defining western prairie fringed orchid (Platanthera praeclara) habitat

    NASA Astrophysics Data System (ADS)

    Knudson, Michael David

    Terrestrial orchids are at the forefront of the discussion about anthropogenically-driven extinction with more species threatened globally than any other plant family, mostly because of loss of habitat. The Western Prairie Fringed Orchid ( Platanthera praeclara) is a threatened species found on the Sheyenne National Grassland in southeast North Dakota, USA. This conservation area that is a vital refuge for this species is subject to management for multiple uses including livestock grazing and recreation. Orchids are subject to continuous monitoring, but knowledge of the relationship between landscape indicators and orchid locations is limited. Research is needed to provide a greater understanding of the landscape relative to orchid habitat to develop conservation management strategies suited to dealing with threats arising from future interactions between land management and use, and climate change. The spatial distribution of orchid habitat was defined using a suite of indicators that characterize topography, moisture, and vegetation cover and compared with orchid point-based field observations. High resolution infrared imagery, a LiDAR-derived DEM, and well observations were used to characterize landscape properties. The NDVI (a measure of vegetation cover), the Topographic Wetness Index (TWI: a measure of moisture on the landscape), the Topographic Position Index (TPI: a measure of position on the landscape), and the depth to groundwater (a measure of the depth from the land surface to the groundwater surface) provided the best set of indicators of orchid habitat. Comparison between orchid locations and landscape indicators identified orchid metrics (+/-2 sigma) used to classify landscape indicators which were combined to create orchid habitat maps. This study supports that distribution of orchid habitat are influenced by the selected landscape indicators, each providing important information to the analysis. Comparison of orchid metrics with groundwater

  4. Bioactive bibenzyl derivatives and fluorenones from Dendrobium nobile.

    PubMed

    Zhang, Xue; Xu, Jie-Kun; Wang, Jue; Wang, Nai-Li; Kurihara, Hiroshi; Kitanaka, Sumumu; Yao, Xin-Sheng

    2007-01-01

    Bioassay-guided fractionation of the 60% ethanol extract of the stems of Dendrobium nobile using the DPPH assay led to the isolation of two new bibenzyl derivatives, nobilin D (1) and nobilin E (2), and a new fluorenone, nobilone (3), together with seven known compounds (4-10). Their structures were determined on the basis of spectroscopic analyses. Compounds 1, 2, 4, 7, 8, and 10 exhibited significant antioxidant activity higher than or equivalent to vitamin C in the DPPH assay, and compounds 1, 3, 4, and 7-10 displayed higher antioxidant activity than vitamin C in the ORAC assay. Compounds 1, 2, and 10 also exhibited stronger inhibitory effects on NO production than resveratrol. PMID:17253844

  5. Cytotoxic bibenzyl dimers from the stems of Dendrobium fimbriatum Hook.

    PubMed

    Xu, Feng-Qing; Xu, Fang-Cheng; Hou, Bo; Fan, Wei-Wei; Zi, Cheng-Ting; Li, Yan; Dong, Fa-Wu; Liu, Yu-Qing; Sheng, Jun; Zuo, Zhi-Li; Hu, Jiang-Miao

    2014-11-15

    The bioassay-guided chemical investigation of the stems of Dendrobium fimbriatum Hook led to the isolation of seven first reported bibenzyl dimers with a linkage of a methylene moiety, fimbriadimerbibenzyls A-G (1-7), together with a new dihydrophenanthrene derivative (S)-2,4,5,9-tetrahydroxy-9,10-dihydrophenanthrene (8) and thirteen known compounds (9-21). The structure of the new compound was established by spectroscopic analysis. Biological evaluation of bibenzyl derivatives against five human cell lines indicated that seven of those compounds exhibited broad-spectrum and cytotoxic activities with IC50 values ranging from 2.2 to 21.2 μM. Those rare bibenzyl dimers exhibited cytotoxic activities in vitro and the cytotoxicity decreased as the number of oxygen-containing groups in the structure decreases. PMID:25316316

  6. Saprotrophic fungal mycorrhizal symbionts in achlorophyllous orchids

    PubMed Central

    Martos, Florent; Perry, Brian A; Padamsee, Mahajabeen; Roy, Mélanie; Pailler, Thierry

    2010-01-01

    Mycoheterotrophic plants are achlorophyllous plants that obtain carbon from their mycorrhizal fungi. They are usually considered to associate with fungi that are (1) specific of each mycoheterotrophic species and (2) mycorrhizal on surrounding green plants, which are the ultimate carbon source of the entire system. Here we review recent works revealing that some mycoheterotrophic plants are not fungal-specific, and that some mycoheterotrophic orchids associate with saprophytic fungi. A re-examination of earlier data suggests that lower specificity may be less rare than supposed in mycoheterotrophic plants. Association between mycoheterotrophic orchids and saprophytic fungi arose several times in the evolution of the two partners. We speculate that this indirectly illustrates why transition from saprotrophy to mycorrhizal status is common in fungal evolution. Moreover, some unexpected fungi occasionally encountered in plant roots should not be discounted as ‘molecular scraps’, since these facultatively biotrophic encounters may evolve into mycorrhizal symbionts in some other plants. PMID:20061806

  7. Pollinator deception in the orchid mantis.

    PubMed

    O'Hanlon, James C; Holwell, Gregory I; Herberstein, Marie E

    2014-01-01

    Mimicry has evolved in contexts such as camouflage, predator deterrence, luring of prey, and pollinator attraction. Mimicry of flowers has until now been demonstrated only in angiosperms, yet it has been hypothesized that the Malaysian orchid mantis Hymenopus coronatus mimics a flower to attract pollinators as prey. Despite the popularity of this charismatic insect, this long-discussed hypothesis has never been experimentally investigated. We found that, as predicted for mimicry, the color of H. coronatus is indistinguishable from the color of sympatric flowers for hymenopteran pollinators. Field experiments show that isolated mantises attract wild pollinators at a rate even higher than flowers and capture these pollinators as prey items. After more than a century of conjecture, we provide the first experimental evidence of pollinator deception in the orchid mantis and the first description of a unique predatory strategy that has not been documented in any other animal species. PMID:24334741

  8. Sex and the Catasetinae (Darwin's favourite orchids).

    PubMed

    Pérez-Escobar, Oscar Alejandro; Gottschling, Marc; Whitten, W Mark; Salazar, Gerardo; Gerlach, Günter

    2016-04-01

    Two sexual systems are predominant in Catasetinae (Orchidaceae), namely protandry (which has evolved in other orchid lineages as well) and environmental sex determination (ESD) being a unique trait among Orchidaceae. Yet, the lack of a robust phylogenetic framework for Catasetinae has hampered deeper insights in origin and evolution of sexual systems. To investigate the origins of protandry and ESD in Catasetinae, we sequenced nuclear and chloroplast loci from 77 species, providing the most extensive data matrix of Catasetinae available so far with all major lineages represented. We used Maximum Parsimony, Maximum Likelihood and Bayesian methods to infer phylogenetic relationships and evolution of sexual systems. Irrespectively of the methods used, Catasetinae were monophyletic in molecular phylogenies, with all established generic lineages and their relationships resolved and highly supported. According to comparative reconstruction approaches, the last common ancestor of Catasetinae was inferred as having bisexual flowers (i.e., lacking protandry and ESD as well), and protandry originated once in core Catasetinae (comprising Catasetum, Clowesia, Cycnoches, Dressleria and Mormodes). In addition, three independent gains of ESD are reliably inferred, linked to corresponding loss of protandry within core Catasetinae. Thus, prior gain of protandry appears as the necessary prerequisite for gain of ESD in orchids. Our results contribute to a comprehensive evolutionary scenario for sexual systems in Catasetinae and more generally in orchids as well. PMID:26708054

  9. Discrimination and similarity evaluation of tissue-cultured and wild Dendrobium species using Fourier transform infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Chen, Nai-dong; Chen, Han; Li, Jun; Sang, Mang-mang; Ding, Shen; Yu, Hao

    2015-04-01

    The FTIR method was applied to evaluate the similarity of tissue-cultured and wild Dendrobium huoshanense C.Z. Tang et S.J. Cheng, Dendrobium officinale Kimura et Migo and Dendrobium moniliforme (Linn.) Sw and discriminate different Dendrobium species, especially D. huoshanense and its main goldbrick Dendrobium henanense J.L. Lu et L.X. Gao. Despite the general pattern of the IR spectra, different intensities, shapes and peak positions were found in the IR spectra of these samples, especially in the range of 1800-600 cm-1, which could be used to discriminate them. The methanol, aqueous extracting procedure and the second derivative transformation obviously enlarged the tiny spectral differences among these samples. The similarity evaluation based on the IR spectra and the second derivative IR spectrum revealed that the similarity of the methanol extracts between tissue-cultured and wild Dendrobiums might be lower than that between different Dendrobium species. The similarities of the powders and aqueous extracts between tissue-cultured and wild Dendrobiums were higher than those between different Dendrobium species. The further principal component analysis showed that the first three components explained 99.7%, 87.7% and 85.1% of data variance for powder, methanol extract and aqueous extract, respectively, demonstrating a good discrimination between samples. Our research suggested that the variations of secondary metabolites between different origins of the investigated Dendrobiums might be higher than what we had supposed. Tissue culture techniques were widely used in the conversation of rare and endangered medicinal amedica, however, our study suggested that the chemical constituents of tissue-cultured plants might be quite different from their wild correspondences.

  10. Epiphytism and pollinator specialization: drivers for orchid diversity?

    PubMed Central

    Gravendeel, Barbara; Smithson, Ann; Slik, Ferry J W; Schuiteman, Andre

    2004-01-01

    Epiphytes are a characteristic component of tropical rainforests. Out of the 25,000 orchid species currently known to science, more than 70% live in tree canopies. Understanding when and how these orchids diversified is vital to understanding the history of epiphytic biomes. We investigated whether orchids managed to radiate so explosively owing to their predominantly epiphytic habit and/or their specialized pollinator systems by testing these hypotheses from a statistical and phylogenetic standpoint. For the first approach, species numbers of 100 randomly chosen epiphytic and terrestrial genera were compared. Furthermore, the mean number of pollinators per orchid species within the five subfamilies was calculated and correlated with their time of diversification and species richness. In the second approach, molecular epiphytic orchid phylogenies were screened for clades with specific suites of epiphytic adaptations. Epiphytic genera were found to be significantly richer in species than terrestrial genera both for orchids and non-orchids. No evidence was found for a positive association between pollinator specialization and orchid species richness. Repeated associations between a small body size, short life cycle and specialized clinging roots of twig epiphytes in Bulbophyllinae and Oncidiinae were discovered. The development of twig epiphytism in the first group seems repeatedly correlated with speciation bursts. PMID:15519970

  11. Orchid conservation in the biodiversity hotspot of southwestern China.

    PubMed

    Liu, Qiang; Chen, Jin; Corlett, Richard T; Fan, XuLi; Yu, DongLi; Yang, HongPei; Gao, JiangYun

    2015-12-01

    Xishuangbanna is on the northern margins of tropical Asia in southwestern China and has the largest area of tropical forest remaining in the country. It is in the Indo-Burma hotspot and contains 16% of China's vascular flora in <0.2% of the country's total area (19,690 km(2) ). Rapid expansion of monoculture crops in the last 20 years, particularly rubber, threatens this region's exceptional biodiversity. To understand the effects of land-use change and collection on orchid species diversity and determine protection priorities, we conducted systematic field surveys, observed markets, interviewed orchid collectors, and then determined the conservation status of all orchids. We identified 426 orchid species in 115 genera in Xishuangbanna: 31% of all orchid species that occur in China. Species richness was highest at 1000-1200 m elevation. Three orchid species were assessed as possibly extinct in the wild, 15 as critically endangered, 82 as endangered, 124 as vulnerable, 186 as least concern, and 16 as data deficient. Declines over 20 years in harvested species suggested over-collection was the major threat, and utility value (i.e., medicinal or ornamental value) was significantly related to endangerment. Expansion of rubber tree plantations was less of a threat to orchids than to other taxa because only 75 orchid species (17.6%) occurred below the 1000-m-elevation ceiling for rubber cultivation, and most of these (46) occurred in nature reserves. However, climate change is projected to lift this ceiling to around 1300 m by 2050, and the limited area at higher elevations reduces the potential for upslope range expansion. The Xishuangbanna Tropical Botanical Garden is committed to achieving zero plant extinctions in Xishuangbanna, and orchids are a high priority. Appropriate in and ex situ conservation strategies, including new protected areas and seed banking, have been developed for every threatened orchid species and are being implemented. PMID:26372504

  12. Discrimination and chemical phylogenetic study of seven species of Dendrobium using infrared spectroscopy combined with cluster analysis

    NASA Astrophysics Data System (ADS)

    Luo, Congpei; He, Tao; Chun, Ze

    2013-04-01

    Dendrobium is a commonly used and precious herb in Traditional Chinese Medicine. The high biodiversity of Dendrobium and the therapeutic needs require tools for the correct and fast discrimination of different Dendrobium species. This study investigates Fourier transform infrared spectroscopy followed by cluster analysis for discrimination and chemical phylogenetic study of seven Dendrobium species. Despite the general pattern of the IR spectra, different intensities, shapes, peak positions were found in the IR spectra of these samples, especially in the range of 1800-800 cm-1. The second derivative transformation and alcoholic extracting procedure obviously enlarged the tiny spectral differences among these samples. The results indicated each Dendrobium species had a characteristic IR spectra profile, which could be used to discriminate them. The similarity coefficients among the samples were analyzed based on their second derivative IR spectra, which ranged from 0.7632 to 0.9700, among the seven Dendrobium species, and from 0.5163 to 0.9615, among the ethanol extracts. A dendrogram was constructed based on cluster analysis the IR spectra for studying the chemical phylogenetic relationships among the samples. The results indicated that D. denneanum and D. crepidatum could be the alternative resources to substitute D. chrysotoxum, D. officinale and D. nobile which were officially recorded in Chinese Pharmacopoeia. In conclusion, with the advantages of high resolution, speediness and convenience, the experimental approach can successfully discriminate and construct the chemical phylogenetic relationships of the seven Dendrobium species.

  13. Transcriptome Analysis of Dendrobium officinale and its Application to the Identification of Genes Associated with Polysaccharide Synthesis

    PubMed Central

    Zhang, Jianxia; He, Chunmei; Wu, Kunlin; Teixeira da Silva, Jaime A.; Zeng, Songjun; Zhang, Xinhua; Yu, Zhenming; Xia, Haoqiang; Duan, Jun

    2016-01-01

    Dendrobium officinale is one of the most important Chinese medicinal herbs. Polysaccharides are one of the main active ingredients of D. officinale. To identify the genes that maybe related to polysaccharides synthesis, two cDNA libraries were prepared from juvenile and adult D. officinale, and were named Dendrobium-1 and Dendrobium-2, respectively. Illumina sequencing for Dendrobium-1 generated 102 million high quality reads that were assembled into 93,881 unigenes with an average sequence length of 790 base pairs. The sequencing for Dendrobium-2 generated 86 million reads that were assembled into 114,098 unigenes with an average sequence length of 695 base pairs. Two transcriptome databases were integrated and assembled into a total of 145,791 unigenes. Among them, 17,281 unigenes were assigned to 126 KEGG pathways while 135 unigenes were involved in fructose and mannose metabolism. Gene Ontology analysis revealed that the majority of genes were associated with metabolic and cellular processes. Furthermore, 430 glycosyltransferase and 89 cellulose synthase genes were identified. Comparative analysis of both transcriptome databases revealed a total of 32,794 differential expression genes (DEGs), including 22,051 up-regulated and 10,743 down-regulated genes in Dendrobium-2 compared to Dendrobium-1. Furthermore, a total of 1142 and 7918 unigenes showed unique expression in Dendrobium-1 and Dendrobium-2, respectively. These DEGs were mainly correlated with metabolic pathways and the biosynthesis of secondary metabolites. In addition, 170 DEGs belonged to glycosyltransferase genes, 37 DEGs were related to cellulose synthase genes and 627 DEGs encoded transcription factors. This study substantially expands the transcriptome information for D. officinale and provides valuable clues for identifying candidate genes involved in polysaccharide biosynthesis and elucidating the mechanism of polysaccharide biosynthesis. PMID:26904032

  14. The use of orchids in Chinese medicine

    PubMed Central

    Bulpitt, Christopher J; Li, Yan; Bulpitt, Pauline F; Wang, Jiguang

    2007-01-01

    In this article, the therapeutic uses of five Chinese medicines that contain orchids are discussed, together with a brief report of some of the animal experimentation undertaken. The impression that these preparations have no therapeutic use may be incorrect. However, herbal preparations have not usually been subject to the rigorous characterization and standardization necessary for clinical study, and persuading practitioners that substances in use for many centuries still need to be tested in randomized controlled clinical trials is proving a significant challenge. PMID:18065708

  15. Germination and seedling establishment in orchids: a complex of requirements

    PubMed Central

    Rasmussen, Hanne N.; Dixon, Kingsley W.; Jersáková, Jana; Těšitelová, Tamara

    2015-01-01

    Background Seedling recruitment is essential to the sustainability of any plant population. Due to the minute nature of seeds and early-stage seedlings, orchid germination in situ was for a long time practically impossible to observe, creating an obstacle towards understanding seedling site requirements and fluctuations in orchid populations. The introduction of seed packet techniques for sowing and retrieval in natural sites has brought with it important insights, but many aspects of orchid seed and germination biology remain largely unexplored. Key Considerations The germination niche for orchids is extremely complex, because it is defined by requirements not only for seed lodging and germination, but also for presence of a fungal host and its substrate. A mycobiont that the seedling can parasitize is considered an essential element, and a great diversity of Basidiomycota and Ascomycota have now been identified for their role in orchid seed germination, with fungi identifiable as imperfect Rhizoctonia species predominating. Specificity patterns vary from orchid species employing a single fungal lineage to species associating individually with a limited selection of distantly related fungi. A suitable organic carbon source for the mycobiont constitutes another key requirement. Orchid germination also relies on factors that generally influence the success of plant seeds, both abiotic, such as light/shade, moisture, substrate chemistry and texture, and biotic, such as competitors and antagonists. Complexity is furthermore increased when these factors influence seeds/seedling, fungi and fungal substrate differentially. Conclusions A better understanding of germination and seedling establishment is needed for conservation of orchid populations. Due to the obligate association with a mycobiont, the germination niches in orchid species are extremely complex and varied. Microsites suitable for germination can be small and transient, and direct observation is difficult

  16. Molecular characterization of natural orchid in South slopes of Mount Merapi, Sleman regency, Yogyakarta

    NASA Astrophysics Data System (ADS)

    Ferdiani, Defika I.; Devi, Fera L.; Koentjana, Johan P.; Milasari, Asri F.; Nur'aini, Indah; Semiarti, Endang

    2015-09-01

    Natural orchid is one of the most important tropical biodiversity. In Indonesia there are ± 6000 species out of 30000 orchids species in the world, of which there are ± 60 species at Mount Merapi. Repetitive eruption of Merapi have wiped out the biodiversity of orchids, therefore the efforts to conserve the orchids and to establish the database of natural orchids in Mount Merapi are needed. The orchid's database can be created based on DNA analysis, and establish barcoding DNA. DNA-barcodes can be used as molecular markers. The different character of morphology usually shows different pattern in DNA fragments. This research aims to characterize the phenotype and genotype of natural orchids of Mt. Merapi based on morphology and the structure of DNA in trnL-F intergenic region of chloroplasts DNA of orchid. Amplified Fragment Length Polymorphism (AFLP) technique was used to characterize the molecular types of orchids in silico of intergenic space area of orchid chloroplast. In this study, 11 species of orchids were characterized based on morphological and molecular characters. The molecular characters were obtained from trnL-F intergenic region of leaves chloroplasts. The data indicates that there is a conserve DNA pattern in all orchids and the distinctive characters of some orchids. In this study, based on trnL-F intergenic region of chloroplast genome, the phylogenetic tree revealed that 11 species of orchids at Mt. Merapi can be grouped into 2 clades, that matched with morphological characters.

  17. Terrestrial orchid conservation in the age of extinction

    PubMed Central

    Swarts, Nigel D.; Dixon, Kingsley W.

    2009-01-01

    Background Conservation through reserves alone is now considered unlikely to achieve protection of plant species necessary to mitigate direct losses of habitat and the pervasive impact of global climate change. Assisted translocation/migration represent new challenges in the face of climate change; species, particularly orchids, will need artificial assistance to migrate from hostile environments, across ecological barriers (alienated lands such as farmlands and built infrastructure) to new climatically buffered sites. The technology and science to underpin assisted migration concepts are in their infancy for plants in general, and orchids, with their high degree of rarity, represent a particularly challenging group for which these principles need to be developed. It is likely that orchids, more than any other plant family, will be in the front-line of species to suffer large-scale extinction events as a result of climate change. Scope The South West Australian Floristic Region (SWAFR) is the only global biodiversity hotspot in Australia and represents an ideal test-bed for development of orchid conservation principles. Orchids comprise 6 % of all threatened vascular plants in the SWAFR, with 76 out of the 407 species known for the region having a high level of conservation risk. The situation in the SWAFR is a portent of the global crisis in terrestrial orchid conservation, and it is a region where innovative conservation solutions will be required if the impending wave of extinction is to be averted. Major threatening processes are varied, and include land clearance, salinity, burning, weed encroachment, disease and pests. This is compounded by highly specialized pollinators (locally endemic native invertebrates) and, in the most threatened groups such as hammer orchids (Drakaea) and spider orchids (Caladenia), high levels of mycorrhizal specialization. Management and development of effective conservation strategies for SWAFR orchids require a wide range of

  18. [Primary study on photosynthetic characteristics of Dendrobium nobile].

    PubMed

    Su, Wenhua; Zhang, Guangfei

    2003-03-01

    With LiCor-6400 Portable Photosynthesis System, carbon dioxide exchange pattern for leaves of Dendrobium nobile during 24 hours were studied in sunny day and rainy day, and the variation of CO2 exchange rate to light intensity was analysed. The results showed that in sunny day D. nobile absorbed CO2 in all day except at midday, at noon photorespiration took place. The CO2 exchange pattern was similar to Crassulacean Acid Metabolism(CAM). In rainy day CO2 uptake was in all day, at night CO2 uptake was monitored at 21:00, then CO2 released from 23:00 to dawn. Light saturation point was 1000 mumol/m2s. Over light saturation point photosynthesis, photoinhibition of photosynthesis will be induced by high-light. Exposed to high-light, the light saturation point and the CO2 uptake velocity would be decreased. With variation of environmental factors, photosynthetic pathway in D. nobile could change from CAM to C3 photosynthetic metabolism. It may be one of main reasons for D. nobile to adapt to the shade-requiring environment, the slow growth and rareness in nature. PMID:12856465

  19. Orchid phylogenomics and multiple drivers of their extraordinary diversification

    PubMed Central

    Givnish, Thomas J.; Spalink, Daniel; Ames, Mercedes; Lyon, Stephanie P.; Hunter, Steven J.; Zuluaga, Alejandro; Iles, William J. D.; Clements, Mark A.; Arroyo, Mary T. K.; Leebens-Mack, James; Endara, Lorena; Kriebel, Ricardo; Neubig, Kurt M.; Whitten, W. Mark; Williams, Norris H.; Cameron, Kenneth M.

    2015-01-01

    Orchids are the most diverse family of angiosperms, with over 25 000 species, more than mammals, birds and reptiles combined. Tests of hypotheses to account for such diversity have been stymied by the lack of a fully resolved broad-scale phylogeny. Here, we provide such a phylogeny, based on 75 chloroplast genes for 39 species representing all orchid subfamilies and 16 of 17 tribes, time-calibrated against 17 angiosperm fossils. A supermatrix analysis places an additional 144 species based on three plastid genes. Orchids appear to have arisen roughly 112 million years ago (Mya); the subfamilies Orchidoideae and Epidendroideae diverged from each other at the end of the Cretaceous; and the eight tribes and three previously unplaced subtribes of the upper epidendroids diverged rapidly from each other between 37.9 and 30.8 Mya. Orchids appear to have undergone one significant acceleration of net species diversification in the orchidoids, and two accelerations and one deceleration in the upper epidendroids. Consistent with theory, such accelerations were correlated with the evolution of pollinia, the epiphytic habit, CAM photosynthesis, tropical distribution (especially in extensive cordilleras), and pollination via Lepidoptera or euglossine bees. Deceit pollination appears to have elevated the number of orchid species by one-half but not via acceleration of the rate of net diversification. The highest rate of net species diversification within the orchids (0.382 sp sp−1 My−1) is 6.8 times that at the Asparagales crown. PMID:26311671

  20. In vitro propagation of Paphiopedilum orchids.

    PubMed

    Zeng, Songjun; Huang, Weichang; Wu, Kunlin; Zhang, Jianxia; da Silva, Jaime A Teixeira; Duan, Jun

    2016-01-01

    Paphiopedilum is one of the most popular and rare orchid genera. Members of the genus are sold and exhibited as pot plants and cut flowers. Wild populations of Paphiopedilum are under the threat of extinction due to over-collection and loss of suitable habitats. A reduction in their commercial value through large-scale propagation in vitro is an option to reduce pressure from illegal collection, to attempt to meet commercial needs and to re-establish threatened species back into the wild. Although they are commercially propagated via asymbiotic seed germination, Paphiopedilum are considered to be difficult to propagate in vitro, especially by plant regeneration from tissue culture. This review aims to cover the most important aspects and to provide an up-to-date research progress on in vitro propagation of Paphiopedilum and to emphasize the importance of further improving tissue culture protocols for ex vitro-derived explants. PMID:25582733

  1. Phenanthrene derivatives from the orchid Coelogyne cristata.

    PubMed

    Majumder, P L; Sen, S; Majumder, S

    2001-10-01

    Coeloginanthridin, a 9,10-dihydrophenanthrene derivative, and coeloginanthrin, the corresponding phenanthrene analogue, were isolated from the orchid Coelogyne cristata which earlier afforded coelogin (1a) and coeloginin (1b). The structures of coeloginanthridin and coeloginanthrin were established as 3,5,7-trihydroxy-1,2-dimethoxy-9,10-dihydrophenanthrene (2a) and 3,5,7-trihydroxy-1,2-dimethoxyphenanthrene (2c), respectively, from spectral and chemical evidence including the conversion of coeloginanthridin triacetate (2b) to coeloginanthrin triacetate (2d) by dehydrogenation with DDQ. In the light of earlier reports on structurally similar compounds, 2a and 2c may have biological activities of phytoalexins and endogenous plant growth regulators. PMID:11576602

  2. 76 FR 78008 - Laboratory Corporation of America Holdings and Orchid Cellmark Inc.; Analysis of Proposed...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-15

    ... Laboratory Corporation of America Holdings and Orchid Cellmark Inc.; Analysis of Proposed Agreement... section below. Write ``LabCorp/Orchid, File No. 111 0155'' on your comment, and file your comment online... January 9, 2012. Write ''LabCorp/Orchid, File No. 111 0155'' on your comment. Your comment--including...

  3. New Workflows for Born-Digital Assets: Managing Charles E. Bracker's Orchid Photographs Collection

    ERIC Educational Resources Information Center

    Hurford, Amanda A.; Runyon, Carolyn F.

    2011-01-01

    Charles E. Bracker was a professor of botany and plant pathology at Purdue University from 1964 to 1999. His late wife, Anri, was an orchid enthusiast who began collecting and housing orchids in the 1980s. In 2009, Bracker's 30,000 digital orchid photographs were donated to Ball State University Libraries, where both of this article's authors…

  4. Donkey Orchid Symptomless Virus: A Viral ‘Platypus’ from Australian Terrestrial Orchids

    PubMed Central

    Wylie, Stephen J.; Li, Hua; Jones, Michael G. K.

    2013-01-01

    Complete and partial genome sequences of two isolates of an unusual new plant virus, designated Donkey orchid symptomless virus (DOSV) were identified using a high-throughput sequencing approach. The virus was identified from asymptomatic plants of Australian terrestrial orchid Diuris longifolia (Common donkey orchid) growing in a remnant forest patch near Perth, western Australia. DOSV was identified from two D. longifolia plants of 264 tested, and from at least one plant of 129 Caladenia latifolia (pink fairy orchid) plants tested. Phylogenetic analysis of the genome revealed open reading frames (ORF) encoding seven putative proteins of apparently disparate origins. A 69-kDa protein (ORF1) that overlapped the replicase shared low identity with MPs of plant tymoviruses (Tymoviridae). A 157-kDa replicase (ORF2) and 22-kDa coat protein (ORF4) shared 32% and 40% amino acid identity, respectively, with homologous proteins encoded by members of the plant virus family Alphaflexiviridae. A 44-kDa protein (ORF3) shared low identity with myosin and an autophagy protein from Squirrelpox virus. A 27-kDa protein (ORF5) shared no identity with described proteins. A 14-kDa protein (ORF6) shared limited sequence identity (26%) over a limited region of the envelope glycoprotein precursor of mammal-infecting Crimea-Congo hemorrhagic fever virus (Bunyaviridae). The putative 25-kDa movement protein (MP) (ORF7) shared limited (27%) identity with 3A-like MPs of members of the plant-infecting Tombusviridae and Virgaviridae. Transmissibility was shown when DOSV systemically infected Nicotiana benthamiana plants. Structure and organization of the domains within the putative replicase of DOSV suggests a common evolutionary origin with ‘potexvirus-like’ replicases of viruses within the Alphaflexiviridae and Tymoviridae, and the CP appears to be ancestral to CPs of allexiviruses (Alphaflexiviridae). The MP shares an evolutionary history with MPs of dianthoviruses, but the other putative

  5. Donkey orchid symptomless virus: a viral 'platypus' from Australian terrestrial orchids.

    PubMed

    Wylie, Stephen J; Li, Hua; Jones, Michael G K

    2013-01-01

    Complete and partial genome sequences of two isolates of an unusual new plant virus, designated Donkey orchid symptomless virus (DOSV) were identified using a high-throughput sequencing approach. The virus was identified from asymptomatic plants of Australian terrestrial orchid Diuris longifolia (Common donkey orchid) growing in a remnant forest patch near Perth, western Australia. DOSV was identified from two D. longifolia plants of 264 tested, and from at least one plant of 129 Caladenia latifolia (pink fairy orchid) plants tested. Phylogenetic analysis of the genome revealed open reading frames (ORF) encoding seven putative proteins of apparently disparate origins. A 69-kDa protein (ORF1) that overlapped the replicase shared low identity with MPs of plant tymoviruses (Tymoviridae). A 157-kDa replicase (ORF2) and 22-kDa coat protein (ORF4) shared 32% and 40% amino acid identity, respectively, with homologous proteins encoded by members of the plant virus family Alphaflexiviridae. A 44-kDa protein (ORF3) shared low identity with myosin and an autophagy protein from Squirrelpox virus. A 27-kDa protein (ORF5) shared no identity with described proteins. A 14-kDa protein (ORF6) shared limited sequence identity (26%) over a limited region of the envelope glycoprotein precursor of mammal-infecting Crimea-Congo hemorrhagic fever virus (Bunyaviridae). The putative 25-kDa movement protein (MP) (ORF7) shared limited (27%) identity with 3A-like MPs of members of the plant-infecting Tombusviridae and Virgaviridae. Transmissibility was shown when DOSV systemically infected Nicotiana benthamiana plants. Structure and organization of the domains within the putative replicase of DOSV suggests a common evolutionary origin with 'potexvirus-like' replicases of viruses within the Alphaflexiviridae and Tymoviridae, and the CP appears to be ancestral to CPs of allexiviruses (Alphaflexiviridae). The MP shares an evolutionary history with MPs of dianthoviruses, but the other putative

  6. Bioguided fractionation and isolation of free radical scavenging components from in vitro propagated chinese medicinal plants Dendrobium tosaense Makino and Dendrobium moniliforme SW.

    PubMed

    Lo, Shu-Fung; Mulabagal, Vanisree; Chen, Chung-Li; Kuo, Chao-Lin; Tsay, Hsin-Sheng

    2004-11-17

    This study was performed to investigate the free radical scavenging active components from in vitro propagated medicinal herbs of the genus Dendrobium, namely, Dendrobium tosaense Makino and Dendrobium moniliforme SW, using a 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical antioxidative assay. Seeds of the capsules derived after 12 weeks of hand-pollination germinated asymbiotically (50-74%) on half-strength Murashige and Skoog's (MS) basal medium with 3% sucrose and solidified with 0.9% Difco agar. Active growth in the germinated seedlings was achieved by reculturing on full-strength MS basal medium supplemented with 8% banana homogenate, 8% potato homogenate, 8% coconut water, 1.5% sucrose, and 0.9% Difco agar. Healthy plantlets transferred to plastic trays containing moss or moss and tree fern successfully acclimatized (84-100%) in the greenhouse. Extracts were prepared from plants grown in the greenhouse for a period of 6 months. Methanolic extracts of D. tosaense and D. moniliforme scavenged DPPH at 95.9 and 83.4%, respectively, at a concentration of 0.4 mg/mL. Therefore, methanolic solubles of D. tosaense and D. moniliforme were subjected to bioguided fractionation and separation by column chromatographic methods individually. After chromatographic separation of these crude extracts, the obtained fractions (Dm 1, Dm 2, Dm 3, Dt 1, Dt 2, and Dt 3) were tested for their activity. Among them, fractions Dm 2 and Dt 1 showed significant antioxidant activity by DPPH radical antioxidative assay. Active fractions were purified further by column chromatography and resulted in identification of the antioxidant components alkyl ferulates from D. moniliforme and quercetin from D. tosaense. PMID:15537296

  7. Stemflow: A Source of Nutrients in some Naturally Growing Epiphytic Orchids of the Sikkim Himalaya.

    PubMed

    Awasthi, O P; Sharma, E; Palni, L M

    1995-01-01

    A study on five naturally growing epiphytic orchids viz., Bulbophyllum affine Lindl., Coelogyne ochracea Lindl., Otochilus porrecta Lindl., Cirrhopetalum cornutum Lindl. and C. cornutum (var.) was carried out in the subtropical belt of Sikkim Himalaya. Stemflow leachates formed the main source of ammonium-N and nitrate-N for uptake by these orchids. Phosphorus concentration in the tissues of these orchids was high. Phosphate-P from stemflow does not seem to be a regular source of phosphorus for these orchids. Absorption/desorption results indicate that organic-N from stemflow leachates is not utilized by these orchids. PMID:21247907

  8. Stemflow: A Source of Nutrients in some Naturally Growing Epiphytic Orchids of the Sikkim Himalaya

    PubMed Central

    Awasthi, O. P.; Sharma, E.; Palni, L. M. S.

    1995-01-01

    A study on five naturally growing epiphytic orchids viz., Bulbophyllum affine Lindl., Coelogyne ochracea Lindl., Otochilus porrecta Lindl., Cirrhopetalum cornutum Lindl. and C. cornutum (var.) was carried out in the subtropical belt of Sikkim Himalaya. Stemflow leachates formed the main source of ammonium-N and nitrate-N for uptake by these orchids. Phosphorus concentration in the tissues of these orchids was high. Phosphate-P from stemflow does not seem to be a regular source of phosphorus for these orchids. Absorption/desorption results indicate that organic-N from stemflow leachates is not utilized by these orchids. PMID:21247907

  9. Independent, specialized invasions of ectomycorrhizal mutualism by two nonphotosynthetic orchids

    PubMed Central

    Taylor, D. Lee; Bruns, Thomas D.

    1997-01-01

    We have investigated the mycorrhizal associations of two nonphotosynthetic orchids from distant tribes within the Orchidaceae. The two orchids were found to associate exclusively with two distinct clades of ectomycorrhizal basidiomycetous fungi over wide geographic ranges. Yet both orchids retained the internal mycorrhizal structure typical of photosynthetic orchids that do not associate with ectomycorrhizal fungi. Restriction fragment length polymorphism and sequence analysis of two ribosomal regions along with fungal isolation provided congruent, independent evidence for the identities of the fungal symbionts. All 14 fungal entities that were associated with the orchid Cephalanthera austinae belonged to a clade within the Thelephoraceae, and all 18 fungal entities that were associated with the orchid Corallorhiza maculata fell within the Russulaceae. Restriction fragment length polymorphism and single-strand conformational polymorphism analysis of ectomycorrhizal tree roots collected adjacent to Cephalanthera showed that (i) the fungi associated internally with Cephalanthera also form typical external ectomycorrhizae and that (ii) ectomycorrhizae formed by other Basidiomycetes were abundant where the orchid grows but these fungi did not associate with the orchid. This is the first proof of ectomycorrhizal epiparasitism in nature by an orchid. We argue that these orchids are cheaters because they do not provide fixed carbon to associated fungi. This view suggests that mycorrhizae, like other ancient mutualisms, are susceptible to cheating. The extreme specificity in these orchids relative to other ectomycorrhizal plants agrees with trends seen in more conventional parasites. PMID:9114020

  10. Start codon targeted (SCoT) and target region amplification polymorphism (TRAP) for evaluating the genetic relationship of Dendrobium species.

    PubMed

    Feng, Shangguo; He, Refeng; Yang, Sai; Chen, Zhe; Jiang, Mengying; Lu, Jiangjie; Wang, Huizhong

    2015-08-10

    Two molecular marker systems, start codon targeted (SCoT) and target region amplification polymorphism (TRAP), were used for genetic relationship analysis of 36 Dendrobium species collected from China. Twenty-two selected SCoT primers produced 337 loci, of which 324 (96%) were polymorphic, whereas 13 TRAP primer combinations produced a total of 510 loci, with 500 (97.8%) of them being polymorphic. An average polymorphism information content of 0.953 and 0.983 was detected using the SCoT and TRAP primers, respectively, showing that a high degree of genetic diversity exists among Chinese Dendrobium species. The partition of clusters in the unweighted pair group method with arithmetic mean dendrogram and principal coordinate analysis plot based on the SCoT and TRAP markers was similar and clustered the 36 Dendrobium species into four main groups. Our results will provide useful information for resource protection and will also be useful to improve the current Dendrobium breeding programs. Our results also demonstrate that SCoT and TRAP markers are informative and can be used to evaluate genetic relationships between Dendrobium species. PMID:25936992

  11. A Modified ABCDE Model of Flowering in Orchids Based on Gene Expression Profiling Studies of the Moth Orchid Phalaenopsis aphrodite

    PubMed Central

    Lee, Ann-Ying; Chen, Chun-Yi; Chang, Yao-Chien Alex; Chao, Ya-Ting; Shih, Ming-Che

    2013-01-01

    Previously we developed genomic resources for orchids, including transcriptomic analyses using next-generation sequencing techniques and construction of a web-based orchid genomic database. Here, we report a modified molecular model of flower development in the Orchidaceae based on functional analysis of gene expression profiles in Phalaenopsis aphrodite (a moth orchid) that revealed novel roles for the transcription factors involved in floral organ pattern formation. Phalaenopsis orchid floral organ-specific genes were identified by microarray analysis. Several critical transcription factors including AP3, PI, AP1 and AGL6, displayed distinct spatial distribution patterns. Phylogenetic analysis of orchid MADS box genes was conducted to infer the evolutionary relationship among floral organ-specific genes. The results suggest that gene duplication MADS box genes in orchid may have resulted in their gaining novel functions during evolution. Based on these analyses, a modified model of orchid flowering was proposed. Comparison of the expression profiles of flowers of a peloric mutant and wild-type Phalaenopsis orchid further identified genes associated with lip morphology and peloric effects. Large scale investigation of gene expression profiles revealed that homeotic genes from the ABCDE model of flower development classes A and B in the Phalaenopsis orchid have novel functions due to evolutionary diversification, and display differential expression patterns. PMID:24265826

  12. Deceived by orchids: sex, science, fiction and Darwin.

    PubMed

    Endersby, Jim

    2016-06-01

    Between 1916 and 1927, botanists in several countries independently resolved three problems that had mystified earlier naturalists - including Charles Darwin: how did the many species of orchid that did not produce nectar persuade insects to pollinate them? Why did some orchid flowers seem to mimic insects? And why should a native British orchid suffer 'attacks' from a bee? Half a century after Darwin's death, these three mysteries were shown to be aspects of a phenomenon now known as pseudocopulation, whereby male insects are deceived into attempting to mate with the orchid's flowers, which mimic female insects; the males then carry the flower's pollen with them when they move on to try the next deceptive orchid. Early twentieth-century botanists were able to see what their predecessors had not because orchids (along with other plants) had undergone an imaginative re-creation: Darwin's science was appropriated by popular interpreters of science, including the novelist Grant Allen; then H.G. Wells imagined orchids as killers (inspiring a number of imitators), to produce a genre of orchid stories that reflected significant cultural shifts, not least in the presentation of female sexuality. It was only after these changes that scientists were able to see plants as equipped with agency, actively able to pursue their own, cunning reproductive strategies - and to outwit animals in the process. This paper traces the movement of a set of ideas that were created in a context that was recognizably scientific; they then became popular non-fiction, then popular fiction, and then inspired a new science, which in turn inspired a new generation of fiction writers. Long after clear barriers between elite and popular science had supposedly been established in the early twentieth century, they remained porous because a variety of imaginative writers kept destabilizing them. The fluidity of the boundaries between makers, interpreters and publics of scientific knowledge was a highly

  13. Identification of medicinal Dendrobium species by phylogenetic analyses using matK and rbcL sequences.

    PubMed

    Asahina, Haruka; Shinozaki, Junichi; Masuda, Kazuo; Morimitsu, Yasujiro; Satake, Motoyoshi

    2010-04-01

    Species identification of five Dendrobium plants was conducted using phylogenetic analysis and the validity of the method was verified. Some Dendrobium plants (Orchidaceae) have been used as herbal medicines but the difficulty in identifying their botanical origin by traditional methods prevented their full modern utilization. Based on the emerging field of molecular systematics as a powerful classification tool, a phylogenetic analysis was conducted using sequences of two plastid genes, the maturase-coding gene (matK) and the large subunit of ribulose 1,5-bisphosphate carboxylase-coding gene (rbcL), as DNA barcodes for species identification of Dendrobium plants. We investigated five medicinal Dendrobium species, Dendrobium fimbriatum, D. moniliforme, D. nobile, D. pulchellum, and D. tosaense. The phylogenetic trees constructed from matK data successfully distinguished each species from each other. On the other hand, rbcL, as a single-locus barcode, offered less species discriminating power than matK, possibly due to its being present with little variation. When results using matK sequences of D. officinale that was deposited in the DNA database were combined, D. officinale and D. tosaense showed a close genetic relationship, which brought us closer to resolving the question of their taxonomic identity. Identification of the plant source as well as the uniformity of the chemical components is critical for the quality control of herbal medicines and it is important that the processed materials be validated. The methods presented here could be applied to the analysis of processed Dendrobium plants and be a promising tool for the identification of botanical origins of crude drugs. PMID:20140532

  14. Carbon and nitrogen gain during the growth of orchid seedlings in nature.

    PubMed

    Stöckel, Marcus; Těšitelová, Tamara; Jersáková, Jana; Bidartondo, Martin I; Gebauer, Gerhard

    2014-04-01

    For germination and establishment, orchids depend on carbon (C) and nutrients supplied by mycorrhizal fungi. As adults, the majority of orchids then appear to become autotrophic. To compare the proportional C and nitrogen (N) gain from fungi in mycoheterotrophic seedlings and in adults, here we examined in the field C and N stable isotope compositions in seedlings and adults of orchids associated with ectomycorrhizal and saprotrophic fungi. Using a new highly sensitive approach, we measured the isotope compositions of seedlings and adults of four orchid species belonging to different functional groups: fully and partially mycoheterotrophic orchids associated with narrow or broad sets of ectomycorrhizal fungi, and two adult putatively autotrophic orchids associated exclusively with saprotrophic fungi. Seedlings of orchids associated with ectomycorrhizal fungi were enriched in (13) C and (15) N similarly to fully mycoheterotrophic adults. Seedlings of saprotroph-associated orchids were also enriched in (13) C and (15) N, but unexpectedly their enrichment was significantly lower, making them hardly distinguishable from their respective adult stages and neighbouring autotrophic plants. We conclude that partial mycoheterotrophy among saprotroph-associated orchids cannot be identified unequivocally based on C and N isotope compositions alone. Thus, partial mycoheterotrophy may be much more widely distributed among orchids than hitherto assumed. PMID:24444001

  15. Preliminary findings on identification of mycorrhizal fungi from diverse orchids in the Central Highlands of Madagascar.

    PubMed

    Yokoya, Kazutomo; Zettler, Lawrence W; Kendon, Jonathan P; Bidartondo, Martin I; Stice, Andrew L; Skarha, Shannon; Corey, Laura L; Knight, Audrey C; Sarasan, Viswambharan

    2015-11-01

    The Orchid flora of Madagascar is one of the most diverse with nearly 1000 orchid taxa, of which about 90% are endemic to this biodiversity hotspot. The Itremo Massif in the Central Highlands of Madagascar with a Highland Subtropical climate range encompasses montane grassland, igneous and metamorphic rock outcrops, and gallery and tapia forests. Our study focused on identifying culturable mycorrhizae from epiphytic, lithophytic, and terrestrial orchid taxa to understand their diversity and density in a spatial matrix that is within the protected areas. We have collected both juvenile and mature roots from 41 orchid taxa for isolating their orchid mycorrhizal fungi (OMF), and to culture, identify, and store in liquid nitrogen for future studies. Twelve operational taxonomic units (OTUs), of three known orchid mycorrhizal genera, were recognized by analysis of internal transcribed spacer (ITS) sequences of 85 isolates, and, by comparing with GenBank database entries, each OTU was shown to have closely related fungi that were also found as orchid associates. Orchid and fungal diversity were greater in gallery forests and open grasslands, which is very significant for future studies and orchid conservation. As far as we know, this is the first ever report of detailed identification of mycorrhizal fungi from Madagascar. This study will help start to develop a programme for identifying fungal symbionts from this unique biodiversity hotspot, which is undergoing rapid ecosystem damage and species loss. The diversity of culturable fungal associates, their density, and distribution within the Itremo orchid hotspot areas will be discussed. PMID:25771863

  16. Native and exotic earthworms affect orchid seed loss

    PubMed Central

    McCormick, Melissa K.; Parker, Kenneth L.; Szlavecz, Katalin; Whigham, Dennis F.

    2013-01-01

    Non-native earthworms have invaded ecosystems around the world but have recently received increased attention as they invaded previously earthworm-free habitats in northern North America. Earthworms can affect plants by ingesting seeds and burying them in the soil. These effects can be negative or positive but are expected to become increasingly negative with decreasing seed size. Orchids have some of the smallest seeds of any plants, so we hypothesized that earthworm consumption of seeds would decrease seed viability and lead to burial of ingested seeds. We used a combination of mesocosms and field measurements to determine whether native and non-native earthworms would affect Goodyera pubescens seed germination by decreasing seed viability through digestion or burial. To determine soil depths at which seed burial would decrease chances of germination, we used field measurements of the abundance of mycorrhizal fungi needed for G. pubescens germination at different soil depths. We found that the combined effects of earthworm ingestion and burial would be expected to result in a loss of 49 % of orchid seeds in mature forests and 68 % of those in successional forests over an average year. Differences in seed ingestion and burial among soils from mature and successional forests were probably driven by differences in their ability to support earthworm biomass and not by differences in earthworm behaviour as a function of soil type. The combined effects of earthworm ingestion and burial have the potential to result in substantial loss of orchid seeds, particularly in successional forests. This effect may slow the ability of orchids to recolonize forests as they proceed through succession. Determining whether this strong effect of earthworms on G. pubescens viability and germination also applies to other orchid species awaits further testing.

  17. Two new dendrocandins with neurite outgrowth-promoting activity from Dendrobium officinale.

    PubMed

    Yang, Liu; Liu, Shou-Jin; Luo, Huai-Rong; Cui, Juan; Zhou, Jun; Wang, Xuan-Jun; Sheng, Jun; Hu, Jiang-Miao

    2015-01-01

    Two new bibenzyl derivatives, dendrocandin T (1) and dendrocandin U (2), together with eight known bibenzyls, were isolated from the stems of Dendrobium officinale. Those compounds were sent for the first time for central nervous system-related bioassay and the results indicated that compounds 3, 4, and 5 have a certain degree of neurite outgrowth-promoting activity, and compounds 1, 2, 6, and 7 also have weak activity. The results indicated that D. officinale used as health food and traditional Chinese medicine "Tiepi Shihu" has a health function of neurotrophic effects. PMID:25289696

  18. In vitro and in vivo antioxidant activity of a water-soluble polysaccharide from dendrobium denneanum

    USGS Publications Warehouse

    Luo, A.; Ge, Z.; Fan, Y.; Chun, Z.; Jin, He X.

    2011-01-01

    The water-soluble crude polysaccharide (DDP) obtained from the aqueous extracts of the stem of Dendrobium denneanum through hot water extraction followed by ethanol precipitation, was found to have an average molecular weight (Mw) of about 484.7 kDa. Monosaccharide analysis revealed that DDP was composed of arabinose, xylose, mannose, glucose and galactose in a molar ratio of 1.00:2.66:8.92:34.20:10.16. The investigation of antioxidant activity both in vitro and in vivo showed that DDP is a potential antioxidant. ?? 2011.

  19. Diversity of mycorrhizal fungi of terrestrial orchids: compatibility webs, brief encounters, lasting relationships and alien invasions.

    PubMed

    Bonnardeaux, Yumiko; Brundrett, Mark; Batty, Andrew; Dixon, Kingsley; Koch, John; Sivasithamparam, K

    2007-01-01

    The diversity of mycorrhizal fungi associated with an introduced weed-like South African orchid (Disa bracteata) and a disturbance-intolerant, widespread, native West Australian orchid (Pyrorchis nigricans) were compared by molecular identification of the fungi isolated from single pelotons. Molecular identification revealed both orchids were associated with fungi from diverse groups in the Rhizoctonia complex with worldwide distribution. Symbiotic germination assays confirmed the majority of fungi isolated from pelotons were mycorrhizal and a factorial experiment uncovered complex webs of compatibility between six terrestrial orchids and 12 fungi from Australia and South Africa. Two weed-like (disturbance-tolerant rapidly spreading) orchids - D. bracteata and the indigenous Australian Microtis media, had the broadest webs of mycorrhizal fungi. In contrast, other native orchids had relatively small webs of fungi (Diuris magnifica and Thelymitra crinita), or germinated exclusively with their own fungus (Caladenia falcata and Pterostylis sanguinea). Orchids, such as D. bracteata and M. media, which form relationships with diverse webs of fungi, had apparent specificity that decreased with time, as some fungi had brief encounters with orchids that supported protocorm formation but not subsequent seedling growth. The interactions between orchid mycorrhizal fungi and their hosts are discussed. PMID:17289365

  20. Coexisting orchid species have distinct mycorrhizal communities and display strong spatial segregation.

    PubMed

    Jacquemyn, Hans; Brys, Rein; Merckx, Vincent S F T; Waud, Michael; Lievens, Bart; Wiegand, Thorsten

    2014-04-01

    Because orchids are dependent on mycorrhizal fungi for germination and establishment of seedlings, differences in the mycorrhizal communities associating with orchids can be expected to mediate the abundance, spatial distribution and coexistence of terrestrial orchids in natural communities. We assessed the small-scale spatial distribution of seven orchid species co-occurring in 25 × 25 m plots in two Mediterranean grasslands. In order to characterize the mycorrhizal community associating with each orchid species, 454 pyrosequencing was used. The extent of spatial clustering was assessed using techniques of spatial point pattern analysis. The community of mycorrhizal fungi consisted mainly of members of the Tulasnellaceae, Thelephoraceae and Ceratobasidiaceae, although sporadically members of the Sebacinaceae, Russulaceae and Cortinariaceae were observed. Pronounced differences in mycorrhizal communities were observed between species, whereas strong clustering and significant segregation characterized the spatial distribution of orchid species. However, spatial segregation was not significantly related to phylogenetic dissimilarity of fungal communities. Our results indicate that co-occurring orchid species have distinctive mycorrhizal communities and show strong spatial segregation, suggesting that mycorrhizal fungi are important factors driving niche partitioning in terrestrial orchids and may therefore contribute to orchid coexistence. PMID:24325257

  1. Four new orchid species from the Lengguru fold belt, West Papua, Indonesia.

    PubMed

    Juswara, Lina; Schuiteman, André; Droissart, Vincent

    2016-01-01

    Bulbophyllum leucoglossum, Dendrobium centrosepalum, Dendrobium taeniocaule, and Taeniophyllum pyriforme are here described as new species, based on herbarium specimens collected from the Lengguru fold-and-thrust belt in the West Papua Bird's neck, Indonesian New Guinea. All four novelties were found growing in submontane forest (elevation > 1000 m a.s.l.) on limestone karst. Information concerning the distribution and habitat for these taxa is provided along with diagnostic features, line drawings, high resolution photographs, and a map of collecting localities. More field studies are required to find additional populations of these new species, in order to better characterize their habitat, ecology and conservation status. PMID:27081349

  2. Four new orchid species from the Lengguru fold belt, West Papua, Indonesia

    PubMed Central

    Juswara, Lina; Schuiteman, André; Droissart, Vincent

    2016-01-01

    Abstract Bulbophyllum leucoglossum, Dendrobium centrosepalum, Dendrobium taeniocaule, and Taeniophyllum pyriforme are here described as new species, based on herbarium specimens collected from the Lengguru fold-and-thrust belt in the West Papua Bird’s neck, Indonesian New Guinea. All four novelties were found growing in submontane forest (elevation > 1000 m a.s.l.) on limestone karst. Information concerning the distribution and habitat for these taxa is provided along with diagnostic features, line drawings, high resolution photographs, and a map of collecting localities. More field studies are required to find additional populations of these new species, in order to better characterize their habitat, ecology and conservation status. PMID:27081349

  3. Two mycoheterotrophic orchids from Thailand tropical dipterocarpacean forests associate with a broad diversity of ectomycorrhizal fungi

    PubMed Central

    Roy, Mélanie; Watthana, Santi; Stier, Anna; Richard, Franck; Vessabutr, Suyanee; Selosse, Marc-André

    2009-01-01

    Background Mycoheterotrophic plants are considered to associate very specifically with fungi. Mycoheterotrophic orchids are mostly associated with ectomycorrhizal fungi in temperate regions, or with saprobes or parasites in tropical regions. Although most mycoheterotrophic orchids occur in the tropics, few studies have been devoted to them, and the main conclusions about their specificity have hitherto been drawn from their association with ectomycorrhizal fungi in temperate regions. Results We investigated three Asiatic Neottieae species from ectomycorrhizal forests in Thailand. We found that all were associated with ectomycorrhizal fungi, such as Thelephoraceae, Russulaceae and Sebacinales. Based on 13C enrichment of their biomass, they probably received their organic carbon from these fungi, as do mycoheterotrophic Neottieae from temperate regions. Moreover, 13C enrichment suggested that some nearby green orchids received part of their carbon from fungi too. Nevertheless, two of the three orchids presented a unique feature for mycoheterotrophic plants: they were not specifically associated with a narrow clade of fungi. Some orchid individuals were even associated with up to nine different fungi. Conclusion Our results demonstrate that some green and mycoheterotrophic orchids in tropical regions can receive carbon from ectomycorrhizal fungi, and thus from trees. Our results reveal the absence of specificity in two mycoheterotrophic orchid-fungus associations in tropical regions, in contrast to most previous studies of mycoheterotrophic plants, which have been mainly focused on temperate orchids. PMID:19682351

  4. Mycorrhizal fungal diversity and community composition in a lithophytic and epiphytic orchid.

    PubMed

    Xing, Xiaoke; Gai, Xuege; Liu, Qiang; Hart, Miranda M; Guo, Shunxing

    2015-05-01

    Some orchid species are present as epiphytes and lithophytes in the same habitat, but little is known about the differences of their mycorrhizal fungal communities. We used Coelogyne viscosa, which occurs both as an epiphyte and a lithophyte, as a study system to investigate orchid mycorrhizal fungal communities in lithophytes and epiphytes in Xishuangbanna National Nature Reserve (Yunnan Province, China). Twenty-three fungal operational taxonomic units (OTUs) from 18 sampling sites were identified. Results indicated that mycorrhizal fungal community composition was different between epi- and lithophytes. When we analyzed the Tulasnellaceae and Sebacinales communities separately, we found that the Sebacinales fungal communities were significantly different in the two growth habitats, but the Tulasnellaceae fungal communities were not. Our results provide evidence for distinct orchid mycorrhiza fungal communities depending on the growth habitat of the orchid. Consistent with some recent investigations of mycorrhizal fungus community composition, this study suggests that for one orchid, growth habitat affects mycorrhizal symbioses. PMID:25319065

  5. On the success of a swindle: pollination by deception in orchids

    NASA Astrophysics Data System (ADS)

    Schiestl, Florian P.

    2005-06-01

    A standing enigma in pollination ecology is the evolution of pollinator attraction without offering reward in about one third of all orchid species. Here I review concepts of pollination by deception, and in particular recent findings in the pollination syndromes of food deception and sexual deception in orchids. Deceptive orchids mimic floral signals of rewarding plants (food deception) or mating signals of receptive females (sexual deception) to attract pollen vectors. In some food deceptive orchids, similarities in the spectral reflectance visible to the pollinator in a model plant and its mimic, and increased reproductive success of the mimic in the presence of the model have been demonstrated. Other species do not mimic specific model plants but attract pollinators with general attractive floral signals. In sexually deceptive orchids, floral odor is the key trait for pollinator attraction, and behaviorally active compounds in the orchids are identical to the sex pheromone of the pollinator species. Deceptive orchids often show high variability in floral signals, which may be maintained by negative frequency-dependent selection, since pollinators can learn and subsequently avoid common deceptive morphs more quickly than rare ones. The evolution of obligate deception in orchids seems paradoxical in the light of the typically lower fruit set than in rewarding species. Pollination by deception, however, can reduce self-pollination and encourage pollen flow over longer distances, thus promoting outbreeding. Although some food deceptive orchids are isolated through postzygotic reproductive barriers, sexually deceptive orchids lack post-mating barriers and species isolation is achieved via specific pollinator attraction. Recent population genetic and phylogenetic investigations suggest gene-flow within subgeneric clades, but pollinator-mediated selection may maintain species-specific floral traits.

  6. Bioactive Phenanthrene and Bibenzyl Derivatives from the Stems of Dendrobium nobile.

    PubMed

    Zhou, Xue-Ming; Zheng, Cai-Juan; Gan, Li-She; Chen, Guang-Ying; Zhang, Xiao-Peng; Song, Xiao-Ping; Li, Gao-Nan; Sun, Chong-Ge

    2016-07-22

    A new enantiomeric pair of spirodiketones, (+)- and (-)-denobilone A (1 and 2), three new phenanthrene derivatives (3-5), and three new biphenanthrenes (22-24), along with 11 known phenanthrene derivatives (6-16), five known bibenzyl derivatives (17-21), and four known biphenanthrenes (25-28), were isolated from Dendrobium nobile. The structures of 1-5 and 22-24 were elucidated using comprehensive spectroscopic methods. (+)-Denobilone and (-)-denobilone A (1 and 2) were isolated as a pair of enantiomers by chiral HPLC. The absolute configurations of (+)- and (-)-denobilone A (1 and 2) were determined by comparing their experimental and calculated electronic circular dichroism spectra. The absolute configuration of denobilone B (3) was determined by X-ray crystallographic analysis. The inhibitory activities of all compounds against nine phytopathogenic fungi and three cancer cell lines were evaluated. PMID:27310249

  7. A polysaccharide from Dendrobium huoshanense prevents hepatic inflammatory response caused by carbon tetrachloride

    PubMed Central

    Tian, Chang-Cheng; Zha, Xue-Qiang; Luo, Jian-Ping

    2015-01-01

    Dendrobium huoshanense is a precious herbal medicine in China, which exhibits a variety of restorative and therapeutic effects. This study aimed at investigating the hepatoprotective effects of a polysaccharide (DHP1A) isolated from D. huoshanense via water extraction, diethylaminoethyl (DEAE) cellulose anion exchange and size exclusion chromatography. The animal experiment indicated that the oral administration of DHP1A obviously reduced the levels of alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase and 8-hydroxy-2′-deoxyguanosine in the serum of mice treated with carbon tetrachloride (CCl4), suggesting the hepatoprotective potential of this polysaccharide. Moreover, DHP1A decreased the expressions of tumor necrosis factor-α, interleukin-1β, monocyte chemoattractant protein-1, macrophage inflammatory protein-2, CD68 and phosphorylated IκBα (p-IκBα) in the CCl4-treated mice. These results revealed that the hepatoprotective effect of DHP1A was partly attributed to its anti-inflammatory action. PMID:26019626

  8. [Elucidating hypoglycemic mechanism of Dendrobium nobile through auxiliary elucidation system for traditional Chinese medicine mechanism].

    PubMed

    Li, Man-man; Zhang, Bai-xia; He, Shuai-bing; Zheng, Rao; Zhang, Yan-ling; Wang, Yun

    2015-10-01

    To build the Dendrobium nobile -T2DM network, and elucidate the molecular mechanism of D. nobile to type 2 diabetes (T2DM). Collect the chemical composition of D. nobile and the targets on T2DM by retrieving database and documents, build the network of D. nobile to T2DM using the entity grammar systems inference rules. The molecular mechanism of D. nobile to T2DM includes: (1) regulating lipid metabolism by lowering triglyceride; (2) reducing insulin resistance; (3) protecting islet cells; (4) promoting the glucose-dependent insulin tropic peptide (GIP) secretion; (5) inhibiting calcium channel. Under the guidance of network pharmacology, through entity grammar systems inference rules we elucidate the molecular mechanism of D. nobile to T2DM, and provide the basis for the further development of health care products based on D. nobile. PMID:26975089

  9. [Study on suitable harvest time of Dendrobium officinale in Yunnan province].

    PubMed

    Zhang, Shan-bao; Zhou, Ke-jun; Zhang, Zhen; Lu, Rui-rui; Li, Xian; Li, Xiao-hua

    2015-09-01

    In order to determine the suitable harvest time of Dendrobium officinale from different regions in Yunnan province, the drying rate, mannose and glucose peak area ratio, extract, contents of polysaccharide and mannose of D. officinale samples collected from six producing areas in Ynnnan province were determined. The results indicate that drying rate and the contents of polysaccharide and mannose arrived the peak from January to April, extract reached a higher content from September to December, and mannose and glucose peak area ratio from October to February of the coming met the requirment of the Chinese Pharmacopoeia. Hence, the suitable harvesting time of D. officinale in Yunnan province is from December to February of the coming year,according to the experimental results and the request of the Chinese Pharmacopoeia. PMID:26983198

  10. [Effects of tree species on polysaccharides content of epiphytic Dendrobium officinale].

    PubMed

    Guo, Ying-Ying; Zhu, Yan; Si, Jin-Ping; Liu, Jing-Jing; Wu, Cheng-Yong; Li, Hui

    2014-11-01

    To reveals the effects of tree species on polysaccharides content of epiphytic Dendrobium officinale. The polysaccharides content of D. officinale attached to living tress in wild or stumps in bionic-facility was determined by phenol-sulfuric acid method. There were extremely significant differences of polysaccharides content of D. officinale attached to different tree species, but the differences had no relationship with the form and nutrition of barks. The polysaccharides content of D. officinale mainly affected by the light intensity of environment, so reasonable illumination favored the accumulation of polysaccharides. Various polysaccharides content of D. officinal from different attached trees is due to the difference of light regulation, but not the form and nutrition of barks. PMID:25775797

  11. Tandem Mass Spectrometry for Structural Identification of Sesquiterpene Alkaloids from the Stems of Dendrobium nobile Using LC-QToF.

    PubMed

    Wang, Yan-Hong; Avula, Bharathi; Abe, Naohito; Wei, Feng; Wang, Mei; Ma, Shuang-Cheng; Ali, Zulfiqar; Elsohly, Mahmoud A; Khan, Ikhlas A

    2016-05-01

    Dendrobium nobile is one of the fundamental herbs in traditional Chinese medicine. Sesquiterpene alkaloids are the main active components in this plant. Due to weak ultraviolet absorption and low content in D. nobile, these sesquiterpene alkaloids have not been extensively studied using chromatographic methods. Herein, tandem mass spectrometry combined with liquid chromatography separation provides a tool for the identification and characterization of the alkaloids from D. nobile. A total of nine sesquiterpene alkaloids were characterized by ultrahigh-performance liquid chromatography tandem mass spectrometry. These alkaloids can be classified into two subgroups that are represented by dendrobine and nobilonine. Tandem mass spectrometric studies revealed the fragmentation pathways of these two subgroup alkaloids that were used for the identification and characterization of other alkaloids in D. nobile. Characterization of these alkaloids using accurate mass and diagnostic fragments provided a reliable methodology for the analysis of D. nobile by ultrahigh-performance liquid chromatography tandem mass spectrometry. The limit of detection was defined as the signal-to-noise ratio equal to 3 : 1. Limits of detection of dendrobine and nobilonine were less than 30 ng/mL. The developed method was applied for the analysis of various Dendrobium species and related dietary supplements. Alkaloids were identified from D. nobile, but not detected from commercial samples including 13 other Dendrobium species and the 7 dietary supplements. PMID:27054915

  12. Orchid Species Richness along Elevational and Environmental Gradients in Yunnan, China.

    PubMed

    Zhang, Shi-Bao; Chen, Wen-Yun; Huang, Jia-Lin; Bi, Ying-Feng; Yang, Xue-Fei

    2015-01-01

    The family Orchidaceae is not only one of the most diverse families of flowering plants, but also one of the most endangered plant taxa. Therefore, understanding how its species richness varies along geographical and environmental gradients is essential for conservation efforts. However, such knowledge is rarely available, especially on a large scale. We used a database extracted from herbarium records to investigate the relationships between orchid species richness and elevation, and to examine how elevational diversity in Yunnan Province, China, might be explained by mid-domain effect (MDE), species-area relationship (SAR), water-energy dynamics (WED), Rapoport's Rule, and climatic variables. This particular location was selected because it is one of the primary centers of distribution for orchids. We recorded 691 species that span 127 genera and account for 88.59% of all confirmed orchid species in Yunnan. Species richness, estimated at 200-m intervals along a slope, was closely correlated with elevation, peaking at 1395 to 1723 m. The elevational pattern of orchid richness was considerably shaped by MDE, SAR, WED, and climate. Among those four predictors, climate was the strongest while MDE was the weakest for predicting the elevational pattern of orchid richness. Species richness showed parabolic responses to mean annual temperature (MAT) and mean annual precipitation (MAP), with maximum richness values recorded at 13.7 to 17.7°C for MAT and 1237 to 1414 mm for MAP. Rapoport's Rule also helped to explain the elevational pattern of species richness in Yunnan, but those influences were not entirely uniform across all methods. These results suggested that the elevational pattern of orchid species richness in Yunnan is collectively shaped by several mechanisms related to geometric constraints, size of the land area, and environments. Because of the dominant role of climate in determining orchid richness, our findings may contribute to a better understanding of

  13. Mycorrhizal preference promotes habitat invasion by a native Australian orchid: Microtis media

    PubMed Central

    De Long, Jonathan R.; Swarts, Nigel D.; Dixon, Kingsley W.; Egerton-Warburton, Louise M.

    2013-01-01

    Background and Aims Mycorrhizal specialization has been shown to limit recruitment capacity in orchids, but an increasing number of orchids are being documented as invasive or weed-like. The reasons for this proliferation were examined by investigating mycorrhizal fungi and edaphic correlates of Microtis media, an Australian terrestrial orchid that is an aggressive ecosystem and horticultural weed. Methods Molecular identification of fungi cultivated from M. media pelotons, symbiotic in vitro M. media seed germination assays, ex situ fungal baiting of M. media and co-occurring orchid taxa (Caladenia arenicola, Pterostylis sanguinea and Diuris magnifica) and soil physical and chemical analyses were undertaken. Key Results It was found that: (1) M. media associates with a broad taxonomic spectrum of mycobionts including Piriformospora indica, Sebacina vermifera, Tulasnella calospora and Ceratobasidium sp.; (2) germination efficacy of mycorrhizal isolates was greater for fungi isolated from plants in disturbed than in natural habitats; (3) a higher percentage of M. media seeds germinate than D. magnifica, P. sanguinea or C. arenicola seeds when incubated with soil from M. media roots; and (4) M. media–mycorrhizal fungal associations show an unusual breadth of habitat tolerance, especially for soil phosphorus (P) fertility. Conclusions The findings in M. media support the idea that invasive terrestrial orchids may associate with a diversity of fungi that are widespread and common, enhance seed germination in the host plant but not co-occurring orchid species and tolerate a range of habitats. These traits may provide the weedy orchid with a competitive advantage over co-occurring orchid species. If so, invasive orchids are likely to become more broadly distributed and increasingly colonize novel habitats. PMID:23275632

  14. Functional Expression of an Orchid Fragrance Gene in Lactococcus lactis

    PubMed Central

    Song, Adelene Ai Lian; Abdullah, Janna O.; Abdullah, Mohd Puad; Shafee, Norazizah; Rahim, Raha A.

    2012-01-01

    Vanda Mimi Palmer (VMP), an orchid hybrid of Vanda tesselata and Vanda Tan Chay Yan is a highly scented tropical orchid which blooms all year round. Previous studies revealed that VMP produces a variety of isoprenoid volatiles during daylight. Isoprenoids are well known to contribute significantly to the scent of most fragrant plants. They are a large group of secondary metabolites which may possess valuable characteristics such as flavor, fragrance and toxicity and are produced via two pathways, the mevalonate (MVA) pathway or/and the 2-C-methyl-D-erythritol-4-phosphate (MEP) pathway. In this study, a sesquiterpene synthase gene denoted VMPSTS, previously isolated from a floral cDNA library of VMP was cloned and expressed in Lactococcus lactis to characterize the functionality of the protein. L. lactis, a food grade bacterium which utilizes the mevalonate pathway for isoprenoid production was found to be a suitable host for the characterization of plant terpene synthases. Through recombinant expression of VMPSTS, it was revealed that VMPSTS produced multiple sesquiterpenes and germacrene D dominates its profile. PMID:22408409

  15. Phylogeny and biology of neotropical orchid bees (Euglossini).

    PubMed

    Cameron, Sydney A

    2004-01-01

    Orchid bees (Euglossini), noted for their brilliant iridescence, are elusive pollinators throughout the American tropics. Males are especially important in the pollination of some orchids, from which they collect aromatic fragrances thought to play a role in territorial display and courtship. The tribe contains approximately 190 described species divided among five genera, distributed from Mexico to central Argentina. Relatively intense study of their biology in the 1960s through the mid-1980s shed light on their nesting biology, chemical ecology, and classification. Vigorous taxonomic research led to the naming of many new species, revisions, and checklists, but phylogenetic studies were scarce. In the two decades following the last comprehensive review, phylogenetic research has resulted in new hypotheses of generic relationships, and further examination of male display has led to additional interpretations. Females in natural and artificial nesting cavities have revealed social interactions and additional details of parasitism within the nest. This review emphasizes areas in need of more study, particularly phylogeny, phylogeography, chemosensory ecology, and comparative behavior, and highlights how historical context can guide future research. PMID:14651469

  16. Functional expression of an orchid fragrance gene in Lactococcus lactis.

    PubMed

    Song, Adelene Ai Lian; Abdullah, Janna O; Abdullah, Mohd Puad; Shafee, Norazizah; Rahim, Raha A

    2012-01-01

    Vanda Mimi Palmer (VMP), an orchid hybrid of Vanda tesselata and Vanda Tan Chay Yan is a highly scented tropical orchid which blooms all year round. Previous studies revealed that VMP produces a variety of isoprenoid volatiles during daylight. Isoprenoids are well known to contribute significantly to the scent of most fragrant plants. They are a large group of secondary metabolites which may possess valuable characteristics such as flavor, fragrance and toxicity and are produced via two pathways, the mevalonate (MVA) pathway or/and the 2-C-methyl-D-erythritol-4-phosphate (MEP) pathway. In this study, a sesquiterpene synthase gene denoted VMPSTS, previously isolated from a floral cDNA library of VMP was cloned and expressed in Lactococcus lactis to characterize the functionality of the protein. L. lactis, a food grade bacterium which utilizes the mevalonate pathway for isoprenoid production was found to be a suitable host for the characterization of plant terpene synthases. Through recombinant expression of VMPSTS, it was revealed that VMPSTS produced multiple sesquiterpenes and germacrene D dominates its profile. PMID:22408409

  17. Are orchid bees at risk? First comparative survey suggests declining populations of forest-dependent species.

    PubMed

    Nemésio, A

    2013-05-01

    The two largest Atlantic Forest remnants in the state of Espírito Santo, eastern Brazil, namely 'Reserva Biológica de Sooretama' (REBIO Sooretama) and 'Reserva Natural Vale' (RNV), were surveyed for their orchid-bee faunas. Seventeen scent baits were used to attract orchid-bee males. Three-thousand, two hundred and twenty-five males belonging to 24 species were actively collected with insect nets during 100 hours in March, April and December, 2009. In comparison with a previous study in the same area twelve years before, it is evident that the abundance of all forest-dependent orchid bees analysed declined around 50%, and it was statistically significant (P = 0.022) for Euglossa marianae Nemésio, 2011, the most sensitive to anthropogenic disturbances of all Atlantic Forest orchid bees. On the other hand, the abundance of populations of species tolerant to open or disturbed areas rose. Possible explanations are discussed. PMID:23917564

  18. Orchid biology: from Linnaeus via Darwin to the 21st century

    PubMed Central

    Fay, Michael F.; Chase, Mark W.

    2009-01-01

    Orchidaceae are the largest family of flowering plants, with at least 24 000 species, and perhaps better than any other family of flowering plants, orchids represent the extreme specializations that are possible. As a result, they have long fascinated luminaries of the botanical world including Linnaeus and Darwin, but the size of the family has historically been an impediment to their study. Specifically, the lack of detailed information about relationships within the family made it difficult to formulate explicit evolutionary hypotheses for such a large group, but the advent of molecular systematics has revolutionized our understanding of the orchids. Their complex life histories make orchids particularly vulnerable to environmental change, and as result many are now threatened with extinction. In this Special Issue we present a series of 20 papers on orchid biology ranging from phylogenetics, floral evolutionary development, taxonomy, mycorrhizal associations, pollination biology, population genetics and conservation. PMID:19654223

  19. Taxonomic turmoil down-under: recent developments in Australian orchid systematics

    PubMed Central

    Hopper, Stephen D.

    2009-01-01

    Background The issue of determining the most appropriate rank for each accepted taxon fuels ongoing controversy throughout systematics. The particularly marked escalation of such issues in modern Australian orchid systematics merits examination, not only because of wider implications in taxonomy but also because of direct effects on studies of comparative biology and conservation management. Scope This paper briefly reviews the causes of recent taxonomic turmoil for Australian orchids and outlines new research opportunities and conservation implications arising from an improved understanding of their molecular phylogenetics. Conclusions DNA sequencing and intensified field work have contributed towards a much improved understanding of Australian orchid systematics. Great progress has been made in discerning monophyletic groups or clades. Fresh interpretations of morphological evolution have been made possible by comparisons with the results of DNA analyses. Significant conceptual shifts from polymorphic species concepts to biological and phylogenetic concepts have also elevated the discovery and description of new species. Consequently, over the past decade, the number of Australian orchid species recognized by taxonomists has risen from approx. 900 to 1200. Similarly, the number of genera recognized by some taxonomists has increased from 110 to 192, resulting in 45% of Australian species/subspecies being assigned a new generic epithet since 2000. At higher taxonomic levels, much of the recent controversy in Australian orchid systematics reflects a divergence in views about where to split and assign formal names within unequivocally monophyletic groups. Differences regarding typification in the case of Caladenia have added additional confusion and complexity. However, new insights into and research opportunities concerning speciation processes in orchids have arisen from the wealth of new data and discrimination of species. Robustly supported molecular analyses of

  20. Mixotrophy of Platanthera minor, an orchid associated with ectomycorrhiza-forming Ceratobasidiaceae fungi.

    PubMed

    Yagame, Takahiro; Orihara, Takamichi; Selosse, Marc-André; Yamato, Masahide; Iwase, Koji

    2012-01-01

    • We investigated the fungal symbionts and carbon nutrition of a Japanese forest photosynthetic orchid, Platanthera minor, whose ecology suggests a mixotrophic syndrome, that is, a mycorrhizal association with ectomycorrhiza (ECM)-forming fungi and partial exploitation of fungal carbon. • We performed molecular identification of symbionts by PCR amplifications of the fungal ribosomal DNA on hyphal coils extracted from P. minor roots. We tested for a (13)C and (15)N enrichment characteristic of mixotrophic plants. We also tested the ectomycorrhizal abilities of orchid symbionts using a new protocol of direct inoculation of hyphal coils onto roots of Pinus densiflora seedlings. • In phylogenetic analyses, most isolated fungi were close to ECM-forming Ceratobasidiaceae clades previously detected from a few fully heterotrophic orchids or environmental ectomycorrhiza surveys. The direct inoculation of fungal coils of these fungi resulted in ectomycorrhiza formation on P. densiflora seedlings. Stable isotope analyses indicated mixotrophic nutrition of P. minor, with fungal carbon contributing from 50% to 65%. • This is the first evidence of photosynthetic orchids associated with ectomycorrhizal Ceratobasidiaceae taxa, confirming the evolution of mixotrophy in the Orchideae orchid tribe, and of ectomycorrhizal abilities in the Ceratobasidiaceae. Our new ectomycorrhiza formation technique may enhance the study of unculturable orchid mycorrhizal fungi. PMID:21995447

  1. Cuticular Hydrocarbons of Orchid Bees Males: Interspecific and Chemotaxonomy Variation

    PubMed Central

    dos Santos, Aline Borba; do Nascimento, Fábio Santos

    2015-01-01

    Recent studies have investigated the composition of compounds that cover the cuticle in social insects, but few studies have focused on solitary bees. Cuticular hydrocarbons may provide a tool for chemotaxonomy, and perhaps they can be used as a complement to morphology and genetic characters in phylogenetic studies. Orchid bees (Tribe Euglossini) are a highly diverse group of Neotropical bees with more than 200 species. Here, the cuticular hydrocarbons of 17 species were identified and statistical analysis revealed 108 compounds, which allowed for the taxonomic classification according to the genera. The most significant compounds discriminating the four genera were (Z)-9-pentacosene, (Z,Z)-pentatriacontene-3, (Z)-9-tricosene, and (Z)-9-heptacosene. The analyses demonstrated the potential use of CHCs to identify different species. PMID:26713612

  2. Trait evolution in the slipper orchid Paphiopedilum (Orchidaceae) in China

    PubMed Central

    Zhang, Feng-Ping; Huang, Jia-Lin; Zhang, Shi-Bao

    2016-01-01

    ABSTRACT The well-known orchid genus Paphiopedilum has attracted much attention from biologists because of its diverse floral traits. Although these traits have been thoroughly described, little is known about their evolutionary trajectory. In this study, we explored their evolutionary patterns and trajectory through phylogenetic analyses and close observations, and 10 characters in 21 Chinese species mapped onto an existing phylogenetic tree. Lip shape, staminode shape, petal shape, and petal width are relatively congruent with molecular phylogenies, thereby validating the existing traditional classification system. All four of those characters, along with flower number, are strongly conserved, and are significantly affected by phylogeny. By contrast, flower color (including that of the dorsal sepal, lip, and petal) is significantly convergent among those examined species and less affected by phylogeny. Therefore, this character is independent of evolution and mainly influenced by environmental factors. All of these characters are key, classical indicators when distinguishing among species within the subgenera Brachypetalum and Paphiopedilum. PMID:26855188

  3. Trait evolution in the slipper orchid paphiopedilum (Orchidaceae) in China.

    PubMed

    Zhang, Feng-Ping; Huang, Jia-Lin; Zhang, Shi-Bao

    2016-01-01

    The well-known orchid genus Paphiopedilum has attracted much attention from biologists because of its diverse floral traits. Although these traits have been thoroughly described, little is known about their evolutionary trajectory. In this study, we explored their evolutionary patterns and trajectory through phylogenetic analyses and close observations, and 10 characters in 21 Chinese species mapped onto an existing phylogenetic tree. Lip shape, staminode shape, petal shape, and petal width are relatively congruent with molecular phylogenies, thereby validating the existing traditional classification system. All four of those characters, along with flower number, are strongly conserved, and are significantly affected by phylogeny. By contrast, flower color (including that of the dorsal sepal, lip, and petal) is significantly convergent among those examined species and less affected by phylogeny. Therefore, this character is independent of evolution and mainly influenced by environmental factors. All of these characters are key, classical indicators when distinguishing among species within the subgenera Brachypetalum and Paphiopedilum. PMID:26855188

  4. Phytotoxic activity of bibenzyl derivatives from the orchid Epidendrum rigidum.

    PubMed

    Hernández-Romero, Yanet; Acevedo, Laura; Sánchez, María de los Angeles; Shier, W Thomas; Abbas, Hamed K; Mata, Rachel

    2005-08-10

    A whole plant chloroform-methanol extract of the orchid Epidendrum rigidum inhibited radicle growth of Amaranthus hypochondriacus seedlings (IC50 = 300 microg/mL). Bioassay-guided fractionation furnished four phytotoxins, namely, gigantol (1), batatasin III (2), 2,3-dimethoxy-9,10-dihydrophenathrene-4,7-diol (9), and 3,4,9-trimethoxyphenanthrene-2,5-diol (11), along with the known flavonoids apigenin, vitexin, and isovetin and the triterterpenoids 24,24-dimethyl-9,19-cyclolanostane-25-en-3beta-ol (14) and 24-methyl-9,19-cyclolanostane-25-en-3beta-ol (15). Stilbenoids 1, 2, 9, and 11 inhibited radicle growth of A. hypochondriacus with IC50 values of 0.65, 0.1, 0.12, and 5.9 microM, respectively. Foliar application of gigantol (1) at 1 microM to 4 week old seedlings of A. hypochondriacus reduced shoot elongation by 69% and fresh weight accumulation by 54%. Bibenzyls 1 and 2, as well as synthetic analogues 4'-hydroxy-3,3',5-trimethoxybibenzyl (3), 3,3',4',5-tetramethoxybibenzyl (4), 3,4'-dihydroxy-5-methoxybibenzyl (5), 3'-O-methylbatatasin III (6), 3,3',5-trihydroxybibenzyl (7), and 3,4',5-trihydroxybibenzyl (8), were tested for phytotoxicity in axenic cultures of the small aquatic plant Lemna pausicostata. All bibenzyls derivatives except 7 and 8 inhibited growth and increased cellular leakage with IC50 values of 89.9-180 and 89.9-166 microM, respectively. The natural and synthetic bibenzyls showed marginal cytotoxicity on animal cells. The results suggest that orchid bibenzyls may be good lead compounds for the development of novel herbicidal agents. PMID:16076106

  5. Orchid-pollinator interactions and potential vulnerability to biological invasion.

    PubMed

    Chupp, Adam D; Battaglia, Loretta L; Schauber, Eric M; Sipes, Sedonia D

    2015-01-01

    Mutualistic relationships between plants and their pollinators have played a major role in the evolution of biodiversity. While the vulnerability of these relationships to environmental change is a major concern, studies often lack a framework for predicting impacts from emerging threats (e.g. biological invasions). The objective of this study was to determine the reliance of Platanthera ciliaris (orange-fringed orchid) on Papilio palamedes (Palamedes swallowtail butterfly) for pollination and the relative availability of alternative pollinators. Recent declines of P. palamedes larval host plants due to laurel wilt disease (LWD) could endanger P. ciliaris populations that rely heavily on this butterfly for pollination. We monitored pollinator visitation and fruit set and measured nectar spur lengths of P. ciliaris flowers and proboscis lengths of its floral visitors in Jackson County, MS, USA. Papilio palamedes was the primary visitor with minimal visitation by Phoebis sennae (cloudless sulfur butterfly). Lengths of P. ciliaris nectar spurs were similar to proboscis lengths of both pollinator species. Fruit set was moderate with access to pollinators (55 ± 10.8 %), yet failed (0 %) when pollinators were excluded. Visitation increased with inflorescence size, but there was no such pattern in fruit set, indicating that fruit set was not limited by pollinator visitation within the range of visitation rates we observed. Our results are supported by historical data that suggest P. palamedes and P. sennae are important pollinators of P. ciliaris. Although P. sennae may provide supplemental pollination service, this is likely constrained by habitat preferences that do not always overlap with those of P. cilaris. Observed declines of P. palamedes due to LWD could severely limit the reproductive success and persistence of P. ciliaris and similar orchid species populations. This empirical-based prediction is among the first to document exotic forest pests and pathogens as

  6. Olfactory specialization for perfume collection in male orchid bees.

    PubMed

    Mitko, Lukasz; Weber, Marjorie G; Ramirez, Santiago R; Hedenström, Erik; Wcislo, William T; Eltz, Thomas

    2016-05-15

    Insects rely on the olfactory system to detect a vast diversity of airborne molecules in their environment. Highly sensitive olfactory tuning is expected to evolve when detection of a particular chemical with great precision is required in the context of foraging and/or finding mates. Male neotropical orchid bees (Euglossini) collect odoriferous substances from multiple sources, store them in specialized tibial pouches and later expose them at display sites, presumably as mating signals to females. Previous analysis of tibial compounds among sympatric species revealed substantial chemical disparity in chemical composition among lineages with outstanding divergence between closely related species. Here, we tested whether specific perfume phenotypes coevolve with matching olfactory adaptations in male orchid bees to facilitate the location and harvest of species-specific perfume compounds. We conducted electroantennographic (EAG) measurements on males of 15 sympatric species in the genus Euglossa that were stimulated with 18 compounds present in variable proportions in male hind tibiae. Antennal response profiles were species-specific across all 15 species, but there was no conspicuous differentiation between closely related species. Instead, we found that the observed variation in EAG activity follows a Brownian motion model of trait evolution, where the probability of differentiation increases proportionally with lineage divergence time. However, we identified strong antennal responses for some chemicals that are present as major compounds in the perfume of the same species, thus suggesting that sensory specialization has occurred within multiple lineages. This sensory specialization was particularly apparent for semi-volatile molecules ('base note' compounds), thus supporting the idea that such compounds play an important role in chemical signaling of euglossine bees. Overall, our study found no close correspondence between antennal responses and behavioral

  7. Recent advances in traditional plant drugs and orchids.

    PubMed

    Kong, Jin-Ming; Goh, Ngoh-Khang; Chia, Lian-Sai; Chia, Tet-Fatt

    2003-01-01

    The main objective of this paper is to review recent advances in plant drug research and developments in orchid study, in an attempt to provide useful references for plant drug studies. Plants have been used as medicine for millennia. Out of estimated 250 000 to 350 000 plant species identified so far, about 35 000 are used worldwide for medicinal purposes. It has been confirmed by WHO that herbal medicines serve the health needs of about 80 percent of the world's population; especially for millions of people in the vast rural areas of developing countries. Meanwhile, consumers in developed countries are becoming disillusioned with modern healthcare and are seeking alternatives. The recent resurgence of plant remedies results from several factors: 1) the effectiveness of plant medicines; 2) the side effect of most modern drugs; and 3) the development of science and technology. It has been estimated that in the mid-1990s over 200 companies and research organizations worldwide are screening plant and animal compounds for medicinal properties. Actually, several important drugs used in modern medicine have come from medicinal plant studies, eg, taxol/paclitaxel, vinblastine, vincristine, topotecan, irinotecan, etoposide, teniposide, etc. As for drugs derived from orchids, some novel discoveries, both in phytochemical and pharmacological properties, were reported by some universities. However, studies on plants are very limited. Only about a third of the million or so species of higher plants have been identified and named by scientists. Of those named, only a tiny fraction has been studied. Nowadays the linking of the indigenous knowledge of medicinal plants to modern research activities provides a new approach, which makes the rate of discovery of drugs much more effective than with random collection. PMID:12511224

  8. Species distribution modelling for conservation of an endangered endemic orchid

    PubMed Central

    Wang, Hsiao-Hsuan; Wonkka, Carissa L.; Treglia, Michael L.; Grant, William E.; Smeins, Fred E.; Rogers, William E.

    2015-01-01

    Concerns regarding the long-term viability of threatened and endangered plant species are increasingly warranted given the potential impacts of climate change and habitat fragmentation on unstable and isolated populations. Orchidaceae is the largest and most diverse family of flowering plants, but it is currently facing unprecedented risks of extinction. Despite substantial conservation emphasis on rare orchids, populations continue to decline. Spiranthes parksii (Navasota ladies' tresses) is a federally and state-listed endangered terrestrial orchid endemic to central Texas. Hence, we aimed to identify potential factors influencing the distribution of the species, quantify the relative importance of each factor and determine suitable habitat for future surveys and targeted conservation efforts. We analysed several geo-referenced variables describing climatic conditions and landscape features to identify potential factors influencing the likelihood of occurrence of S. parksii using boosted regression trees. Our model classified 97 % of the cells correctly with regard to species presence and absence, and indicated that probability of existence was correlated with climatic conditions and landscape features. The most influential variables were mean annual precipitation, mean elevation, mean annual minimum temperature and mean annual maximum temperature. The most likely suitable range for S. parksii was the eastern portions of Leon and Madison Counties, the southern portion of Brazos County, a portion of northern Grimes County and along the borders between Burleson and Washington Counties. Our model can assist in the development of an integrated conservation strategy through: (i) focussing future survey and research efforts on areas with a high likelihood of occurrence, (ii) aiding in selection of areas for conservation and restoration and (iii) framing future research questions including those necessary for predicting responses to climate change. Our model could also

  9. Intestinal immunomodulating activity and structural characterization of a new polysaccharide from stems of Dendrobium officinale.

    PubMed

    Xie, Song-Zi; Liu, Bing; Zhang, Dan-Dan; Zha, Xue-Qiang; Pan, Li-Hua; Luo, Jian-Ping

    2016-06-15

    A homogeneous polysaccharide fraction (DOP-W3-b) with a high intestinal immunomodulating activity was obtained from the stems of Dendrobium officinale through a bioactivity-guided sequential isolation procedure based on the screening of Peyer's patch-mediated immunomodulating activity. Oral administration experiments of mice showed that DOP-W3-b could effectively regulate intestinal mucosal immune activity by changing intestinal mucosal structures, promoting the secretions of cytokines from Peyer's patches (PPs) and mesenteric lymph nodes (MLNs), and increasing the production of secretory immunoglobulin A (sIgA) in the lamina propria. Structure analysis indicated that DOP-W3-b was composed of mannose and glucose in a molar ratio of 4.5 with a relatively low molecular weight of 1.543 × 10(4) Da, and its repeat unit contained a backbone consisting of β-(1→4)-d-Manp, β-(1→4)-d-Glcp and β-(1→3,6)-d-Manp residues, a branch consisting of β-(1→4)-d-Manp, β-(1→4)-d-Glcp and terminal β-d-Glcp, and O-acetyl groups attached to O-2 of β-(1→4)-d-Manp. These results suggested that DOP-W3-b was a new polysaccharide with an essential potential for modulating body's immune functions. PMID:27225227

  10. Preventive effect of Dendrobium candidum Wall. ex Lindl. on activated carbon-induced constipation in mice

    PubMed Central

    WANG, RUI; SUN, PENG; ZHOU, YALIN; ZHAO, XIN

    2015-01-01

    The aim of this study was to investigate the effects of Dendrobium candidum Wall. ex Lindl. (D. candidum) on activated carbon-induced constipation in ICR mice. ICR mice were orally administered D. candidum for 9 days. Body weight, defecation status, gastrointestinal (GI) transit and defecation times, in addition to the levels of motilin (MTL), gastrin (Gas), endothelin (ET), somatostatin (SS), acetylcholinesterase (AChE), substance P (SP) and vasoactive intestinal peptide (VIP) in serum were used to evaluate the preventive effects of D. candidum on constipation. The laxative drug bisacodyl acted as a positive control. The time to the first defecation of a black stool for the normal, control, bisacodyl-treated (100 mg/kg), 200 and 400 mg/kg D. candidum-treated mice was 84, 202, 126, 161 and 142 min, respectively. Following the consumption of 200 and 400 mg/kg D. candidum or bisacodyl (100 mg/kg), the GI transit was reduced to 57.7, 74.6 and 90.2%, respectively, of the transit in normal mice. The serum levels of MTL, Gas, ET, AChE, SP and VIP were significantly increased and the serum levels of SS were reduced in the mice treated with D. candidum compared with those in the untreated control mice (P<0.05). These results demonstrate that D. candidum has preventive effects on constipation in mice, and a greater functional activity was observed when a higher concentration was administered. PMID:25574235

  11. Dendrobium chrysotoxum Lindl. Alleviates Diabetic Retinopathy by Preventing Retinal Inflammation and Tight Junction Protein Decrease

    PubMed Central

    Yu, Zengyang; Gong, Chenyuan; Lu, Bin; Yang, Li; Sheng, Yuchen; Ji, Lili; Wang, Zhengtao

    2015-01-01

    Diabetic retinopathy (DR) is a serious complication of diabetes mellitus. This study aimed to observe the alleviation of the ethanol extract of Dendrobium chrysotoxum Lindl. (DC), a traditional Chinese herbal medicine, on DR and its engaged mechanism. After DC (30 or 300 mg/kg) was orally administrated, the breakdown of blood retinal barrier (BRB) in streptozotocin- (STZ-) induced diabetic rats was attenuated by DC. Decreased retinal mRNA expression of tight junction proteins (including occludin and claudin-1) in diabetic rats was also reversed by DC. Western blot analysis and retinal immunofluorescence staining results further confirmed that DC reversed the decreased expression of occludin and claudin-1 proteins in diabetic rats. DC reduced the increased retinal mRNA expressions of intercellular adhesion molecule-1 (ICAM-1), tumor necrosis factor α (TNFα), interleukin- (IL-) 6, and IL-1β in diabetic rats. In addition, DC alleviated the increased 1 and phosphorylated p65, IκB, and IκB kinase (IKK) in diabetic rats. DC also reduced the increased serum levels of TNFα, interferon-γ (IFN-γ), IL-6, IL-1β, IL-8, IL-12, IL-2, IL-3, and IL-10 in diabetic rats. Therefore, DC can alleviate DR by inhibiting retinal inflammation and preventing the decrease of tight junction proteins, such as occludin and claudin-1. PMID:25685822

  12. Antiproliferative effect of Dendrobium catenatum Lindley polypeptides against human liver, gastric and breast cancer cell lines.

    PubMed

    Zheng, Qiuping; Qiu, Daoshou; Liu, Xiaojin; Zhang, Lei; Cai, Shike; Zhang, Xuewu

    2015-05-01

    Dendrobium catenatum Lindley is a precious plant with both dietary and medicinal applications. However, the antiproliferative activity of D. catenatum-derived peptides has not been investigated. In this study, the whole proteins of D. catenatum were extracted, hydrolysis with three proteases (alcalase 2.4L, alcalase 37017 and trypsin) was performed, and gel filtration chromatography was employed to obtain nine fractions. Fraction A3 possessed the best antiproliferative activity in vitro, with percentage inhibitions of 73.38%, 78.91% and 86.8% against HepG-2, SGC-7901 and MCF-7 cancer cells, respectively, and an inhibition of only 5.52% against L-O2 normal liver cells at 500 μg mL(-1). Subsequently, mass spectrometry revealed the existence of 10 alcalase-derived peptides in fraction A3, and the sequences of the three most abundant peptides were determined by de novo sequencing as: RHPFDGPLLPPGD, RCGVNAFLPKSYLVHFGWKLLFHFD and KPEEVGGAGDRWTC. Moreover, these peptides were synthesized and their antiproliferative activities in vitro were also confirmed. This suggests that fraction A3 may be promising for use in food and pharmaceutical applications. PMID:25811957

  13. [Variation of polysaccharides and alcohol-soluble extracts content of Dendrobium officinale].

    PubMed

    Yu, Qiao-xian; Guo, Ying-ying; Si, Jin-ping; Wu, Ling-shang; Wang, Lin-hua

    2014-12-01

    To reveal the variation of polysaccharides and alcohol-soluble extract contents of Dendrobium officinale, the polysaccharides and alcohol-soluble extracts contents of three D. officinale strains were determined by phenol-sulfuric acid method and hot-dip method, respectively. The results showed that the contents of polysaccharides and alcohol-soluble extracts and their total content were significantly different among D. officinale samples collected in different periods, and the variations were closely related to the phenology of D. officinale. Additionally, the quality variation of polysaccharides was closely related to the flowering of D. officinale, while the alcohol-soluble extracts was closely associated to the formation and germination of buds. According to the dynamic variation of these two compounds, it is more reasonable to harvest D. officinale at biennials pre-bloom than at specific harvesting month considering polysaccharides content. It is better to harvest before the germination of buds considering alcohol-soluble extracts. While with regards to both polysaccharides and alcohol-soluble extract, it is better to harvest this plant at the period from the sprouting to pre-bloom next year. PMID:25898575

  14. Polysaccharide of Dendrobium huoshanense activates macrophages via toll-like receptor 4-mediated signaling pathways.

    PubMed

    Xie, Song-Zi; Hao, Ran; Zha, Xue-Qiang; Pan, Li-Hua; Liu, Jian; Luo, Jian-Ping

    2016-08-01

    The present work aimed at investigating the pattern recognition receptor (PRR) and immunostimulatory mechanism of a purified Dendrobium huoshanense polysaccharide (DHP). We found that DHP could bind to the surface of macrophages and stimulate macrophages to secrete NO, TNF-α and IL-1β. To unravel the mechanism for the binding of DHP to macrophages, flow cytometry, confocal laser-scanning microscopy, affinity electrophoresis, SDS-PAGE and western blotting were employed to verify the type of PRR responsible for the recognition of DHP by RAW264.7 macrophages and peritoneal macrophages of C3H/HeN and C3H/HeJ macrophages. Results showed that toll-like receptor 4 (TLR4) was an essential receptor for macrophages to directly bind DHP. Further, the phosphorylation of ERK, JNK, Akt and p38 were observed to be time-dependently promoted by DHP, as well as the nuclear translocation of NF-κB p65. These results suggest that DHP activates macrophages via its direct binding to TLR4 to trigger TLR4 signaling pathways. PMID:27112877

  15. Dendrobium officinale Prevents Early Complications in Streptozotocin-Induced Diabetic Rats.

    PubMed

    Hou, Shao-Zhen; Liang, Chu-Yan; Liu, Hua-Zhen; Zhu, Dong-Mei; Wu, Ya-Yun; Liang, Jian; Zhao, Ya; Guo, Jian-Ru; Huang, Song; Lai, Xiao-Ping

    2016-01-01

    Background. Dendrobium officinale (DO) Kimura et Migo is a precious Chinese herb that is considered beneficial for health due to its antioxidant and antidiabetes properties, and so on. In this research, we try to determine the preventive effect of DO on the early complications of STZ-induced diabetic rats. Methods. Type 1 diabetic rats were produced with a single intraperitoneal injection of STZ (50 mg/kg). DO (1 g/kg/day) was then orally administered for 5 weeks. Blood glucose, TC, TG, BUN, CREA, and GSH-PX levels were determined, and electroretinographic activity and hypoalgesia were investigated. Pathological sections of the eyes, hearts, aortas, kidneys, and livers were analyzed. Results. Treatment with DO significantly attenuated the serum levels of TC, TG, BUN, and CREA, markedly increased the amplitudes of ERG a- and b-waves and Ops, and reduced the hypoalgesia and histopathological changes of vital organs induced by hyperglycemia. The protective effect of DO in diabetic rats may be associated with its antioxidant activity, as evidenced by the marked increase in the serum level of glutathione peroxidase. However, DO had no significant effect on blood glucose levels and bodyweight of diabetic rats. Conclusions. DO supplementation is an effective treatment to prevent STZ-induced diabetic complications. PMID:27034693

  16. [Effect of strains and parts on amino acids of Dendrobium officinale].

    PubMed

    Liu, Zhen-peng; Guo, Ying-ying; Iu, Jing-jing; Si, Jin-ping; Wu, Ling-shang; Zhang, Xin-feng

    2015-04-01

    The aim of the paper is to reveals the variations of Dendrobium officinale amino acids in different strains and parts for breeding excellent varieties, and providing scientific basis for the expanding of medicinal or edible parts. The contents of 17 amino acids in 11 strains of D. officinale were determined by hydrochloric acid hydrolysis method. The total amino acids content of leaves was from 6.76 to 7.97 g per 100 g, and the stems was from 1.61 to 2.44 g per 100 g. As the content of amino acids in leaves was significantly higher than that of stems, and the composition was close to the ideal protein standard proposed by FAO/WHO. The leaves of D. officinale had the good prospect for the development of functional foods. The 9 x 66 strain which with high yield and polysaccharide content had the highest amino acids content both in stems and leaves, indicated crossbreeding could improve the quality of varieties. Compared the amino acids content of D. officinale in two main harvest periods, the harvest time has a significant impact on amino acids content of D. officinale. This study demonstrates that the harvesting time of D. officinale stems is suitable for leaves as well, which is the period before bolssom. PMID:26281581

  17. Dendrobium officinale Prevents Early Complications in Streptozotocin-Induced Diabetic Rats

    PubMed Central

    Hou, Shao-zhen; Liang, Chu-yan; Liu, Hua-zhen; Zhu, Dong-mei; Wu, Ya-yun; Liang, Jian; Zhao, Ya; Guo, Jian-ru; Huang, Song; Lai, Xiao-Ping

    2016-01-01

    Background. Dendrobium officinale (DO) Kimura et Migo is a precious Chinese herb that is considered beneficial for health due to its antioxidant and antidiabetes properties, and so on. In this research, we try to determine the preventive effect of DO on the early complications of STZ-induced diabetic rats. Methods. Type 1 diabetic rats were produced with a single intraperitoneal injection of STZ (50 mg/kg). DO (1 g/kg/day) was then orally administered for 5 weeks. Blood glucose, TC, TG, BUN, CREA, and GSH-PX levels were determined, and electroretinographic activity and hypoalgesia were investigated. Pathological sections of the eyes, hearts, aortas, kidneys, and livers were analyzed. Results. Treatment with DO significantly attenuated the serum levels of TC, TG, BUN, and CREA, markedly increased the amplitudes of ERG a- and b-waves and Ops, and reduced the hypoalgesia and histopathological changes of vital organs induced by hyperglycemia. The protective effect of DO in diabetic rats may be associated with its antioxidant activity, as evidenced by the marked increase in the serum level of glutathione peroxidase. However, DO had no significant effect on blood glucose levels and bodyweight of diabetic rats. Conclusions. DO supplementation is an effective treatment to prevent STZ-induced diabetic complications. PMID:27034693

  18. Chemical properties and antioxidant activity of a water-soluble polysaccharide from Dendrobium officinale.

    PubMed

    Luo, Qiu-Lian; Tang, Zhuan-Hui; Zhang, Xue-Feng; Zhong, Yong-Hong; Yao, Su-Zhi; Wang, Li-Sheng; Lin, Cui-Wu; Luo, Xuan

    2016-08-01

    In this report, a water-soluble polysaccharide was obtained from the dried stems of Dendrobium officinale Kimura et Migo by hot-water (70-75°C) extraction and 85% ethanol precipitation, and successively purification by DEAE-cellulose anion-exchange chromatography and gel-permeation chromatography. The D. officinale polysaccharide (DOP) has a molecular weight of 8500Da. Monosaccharide composition analysis reveals that DOP is composed of mannose, glucose, and arabinose with a trace of galacturonic acid in a molar ratio of 6.2:2.3:2.1:0.1. Periodate oxidation-smith degradation and 1D and 2D NMR spectroscopy analysis suggest the predominance of mannose and glucose, and it contains a 2-O-acetylglucomannan and (1→4)-linked-β-d-mannopyranosyl and (1→4)-linked-β-d-glucopyranosyl residues. Atomic force microscope shows that DOP mainly exists as rod-shaped chains, supporting high degrees of polymerization. The antioxidant activities of the polysaccharide in vitro assay indicate that DOP has good scavenging activity of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, higher scavenging activity of hydroxyl radical, and metal chelating activities. PMID:27131730

  19. [Quantitive variation of polysaccharides and alcohol-soluble extracts in F1 generation of Dendrobium officinale].

    PubMed

    Zhang, Xiao-Ling; Liu, Jing-Jing; Wu, Ling-Shang; Si, Jin-Ping; Guo, Ying-Ying; Yu, Jie; Wang, Lin-Hua

    2013-11-01

    Using phenol-sulfuric acid method and hot-dip method of alcohol-soluble extracts, the contents of polysaccharides and alcohol-soluble extracts in 11 F1 generations of Dendrobium officinale were determined. The results showed that the polysaccharides contents in samples collected in May and February were 32.89%-43.07% and 25.77%-35.25%, respectively, while the extracts contents were 2.81%-4.85% and 7.90%-17.40%, respectively. They were significantly different among families. The content of polysaccharides in offspring could be significantly improved by hybridization between parents with low and high polysaccharides contents, and the hybrid vigor was obvious. Cross breeding was an effective way for breeding new varieties with higher polysaccharides contents. Harvest time would significantly affect the contents of polysaccharides and alcohol-soluble extracts. The contents of polysaccharides in families collected in May were higher than those of polysaccharides in families collected in February, but the extracts content had the opposite variation. The extents of quantitative variation of polysaccharides and alcohol-soluble extracts were different among families, and each family had its own rules. It would be significant in giving full play to their role as the excellent varieties and increasing effectiveness by studying on the quantitative accumulation regularity of polysaccharides and alcohol-soluble extracts in superior families (varieties) of D. officinale to determine the best harvesting time. PMID:24494555

  20. [Field experiment of F1 generation and superior families selection of Dendrobium officinale].

    PubMed

    Zhang, Xiao-Ling; Si, Jin-Ping; Wu, Ling-Shang; Guo, Ying-Ying; Yu, Jie; Wang, Lin-Hua

    2013-11-01

    Based on randomized block design of experiment, agronomic traits and yields of 14 F1 generations of Dendrobium officinale were determined. The results showed that the differences in agronomic traits and yields among families were significant, and the hybrid vigor was obvious. Families of 6b x 2a, 9 x 66 and 78 x 69 were selected with the remarkable superiority of yields, agronomic traits and product customization. Correlation analysis between agronomic traits and yields showed that plant height, stem diameter, leaf number, blade length and blade width were all significantly correlated with biological yields and economic yields. Among which, stem diameter, leaf number and blade length were the most significant, and an optimal linear regression model could be established. When the number of shoots was fewer than 4.5, both biological yields and economic yields increased with the increasing number of shoots, but it could not much affect yields when the number of shoots was larger than 4.5. Shoots number, stem diameter and leaf index were basic stability when compared biennial traits to annual, which could be used for early selection. PMID:24558865

  1. The importance of associations with saprotrophic non-Rhizoctonia fungi among fully mycoheterotrophic orchids is currently under-estimated: novel evidence from sub-tropical Asia

    PubMed Central

    Lee, Yung-I; Yang, Chih-Kai; Gebauer, Gerhard

    2015-01-01

    Background and Aims Most fully mycoheterotrophic (MH) orchids investigated to date are mycorrhizal with fungi that simultaneously form ectomycorrhizas with forest trees. Only a few MH orchids are currently known to be mycorrhizal with saprotrophic, mostly wood-decomposing, fungi instead of ectomycorrhizal fungi. This study provides evidence that the importance of associations between MH orchids and saprotrophic non-Rhizoctonia fungi is currently under-estimated. Methods Using microscopic techniques and molecular approaches, mycorrhizal fungi were localized and identified for seven MH orchid species from four genera and two subfamilies, Vanilloideae and Epidendroideae, growing in four humid and warm sub-tropical forests in Taiwan. Carbon and nitrogen stable isotope natural abundances of MH orchids and autotrophic reference plants were used in order to elucidate the nutritional resources utilized by the orchids. Key Results Six out of the seven MH orchid species were mycorrhizal with either wood- or litter-decaying saprotrophic fungi. Only one orchid species was associated with ectomycorrhizal fungi. Stable isotope abundance patterns showed significant distinctions between orchids mycorrhizal with the three groups of fungal hosts. Conclusions Mycoheterotrophic orchids utilizing saprotrophic non-Rhizoctonia fungi as a carbon and nutrient source are clearly more frequent than hitherto assumed. On the basis of this kind of nutrition, orchids can thrive in deeply shaded, light-limiting forest understoreys even without support from ectomycorrhizal fungi. Sub-tropical East Asia appears to be a hotspot for orchids mycorrhizal with saprotrophic non-Rhizoctonia fungi. PMID:26113634

  2. In vitro Antioxidant of a Water-Soluble Polysaccharide from Dendrobium fimhriatum Hook.var.oculatum Hook

    PubMed Central

    Luo, Aoxue; Fan, Yijun

    2011-01-01

    A water-soluble crude polysaccharide (DFHP) obtained from the aqueous extracts of the stem of Dendrobium fimhriatum Hook.var.oculatum Hook through hot water extraction followed by ethanol precipitation, was found to have an average molecular weight (Mw) of about 209.3 kDa. Monosaccharide analysis revealed that DFHP was composed of mannose, glucose and galactose in a content ratio of 37.52%; 43.16%; 19.32%. The investigation of antioxidant activity in vitro showed that DFHP is a potential antioxidant. PMID:21747725

  3. Tandem Mass Spectrometry for Structural Identification of Sesquiterpene alkaloids from the stems of dendrobium nobile using LC-QToF3

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dendrobium nobile is one of the fundamental herbs in traditional Chinese medicine (TCM). Sesquiterpene alkaloids are the main active components in this plant. Due to weak ultraviolet absorption and low content in D. nobile, these sesquiterpene alkaloids have not been extensively studied using chroma...

  4. Orchid Species Richness along Elevational and Environmental Gradients in Yunnan, China

    PubMed Central

    Zhang, Shi-Bao; Chen, Wen-Yun; Huang, Jia-Lin; Bi, Ying-Feng; Yang, Xue-Fei

    2015-01-01

    The family Orchidaceae is not only one of the most diverse families of flowering plants, but also one of the most endangered plant taxa. Therefore, understanding how its species richness varies along geographical and environmental gradients is essential for conservation efforts. However, such knowledge is rarely available, especially on a large scale. We used a database extracted from herbarium records to investigate the relationships between orchid species richness and elevation, and to examine how elevational diversity in Yunnan Province, China, might be explained by mid-domain effect (MDE), species–area relationship (SAR), water–energy dynamics (WED), Rapoport’s Rule, and climatic variables. This particular location was selected because it is one of the primary centers of distribution for orchids. We recorded 691 species that span 127 genera and account for 88.59% of all confirmed orchid species in Yunnan. Species richness, estimated at 200-m intervals along a slope, was closely correlated with elevation, peaking at 1395 to 1723 m. The elevational pattern of orchid richness was considerably shaped by MDE, SAR, WED, and climate. Among those four predictors, climate was the strongest while MDE was the weakest for predicting the elevational pattern of orchid richness. Species richness showed parabolic responses to mean annual temperature (MAT) and mean annual precipitation (MAP), with maximum richness values recorded at 13.7 to 17.7°C for MAT and 1237 to 1414 mm for MAP. Rapoport’s Rule also helped to explain the elevational pattern of species richness in Yunnan, but those influences were not entirely uniform across all methods. These results suggested that the elevational pattern of orchid species richness in Yunnan is collectively shaped by several mechanisms related to geometric constraints, size of the land area, and environments. Because of the dominant role of climate in determining orchid richness, our findings may contribute to a better

  5. Perspectives on MADS-box expression during orchid flower evolution and development.

    PubMed

    Mondragón-Palomino, Mariana

    2013-01-01

    The diverse morphology of orchid flowers and their complex, often deceptive strategies to become pollinated have fascinated researchers for a long time. However, it was not until the 20th century that the ontogeny of orchid flowers, the genetic basis of their morphology and the complex phylogeny of Orchidaceae were investigated. In parallel, the improvement of techniques for in vitro seed germination and tissue culture, together with studies on biochemistry, physiology, and cytology supported the progress of what is now a highly productive industry of orchid breeding and propagation. In the present century both basic research in orchid flower evo-devo and the interest for generating novel horticultural varieties have driven the characterization of many members of the MADS-box family encoding key regulators of flower development. This perspective summarizes the picture emerging from these studies and discusses the advantages and limitations of the comparative strategy employed so far. I address the growing role of natural and horticultural mutants in these studies and the emergence of several model species in orchid evo-devo and genomics. In this context, I make a plea for an increasingly integrative approach. PMID:24065980

  6. Mycorrhizal compatibility and symbiotic reproduction of Gavilea australis, an endangered terrestrial orchid from south Patagonia.

    PubMed

    Fracchia, Sebastián; Aranda-Rickert, Adriana; Flachsland, Eduardo; Terada, Graciela; Sede, Silvana

    2014-11-01

    Gavilea australis is a terrestrial orchid endemic from insular south Argentina and Chile. Meeting aspects of mycorrhizal fungi identity and compatibility in this orchid species is essential for propagation and conservation purposes. These knowledge represent also a first approach to elucidate the mycorrhizal specificity of this species. In order to evaluate both the mycorrhizal compatibility and the symbiotic seed germination of G. australis, we isolated and identified its root endophytic fungal strains as well as those from two sympatric species: Gavilea lutea and Codonorchis lessonii. In addition, we tested two other strains isolated from allopatric terrestrial orchid species from central Argentina. All fungal strains formed coilings and pelotons inside protocorms and promoted, at varying degrees, seed germination, and protocorm development until seedlings had two to three leaves. These results suggest a low mycorrhizal specificity of G. australis and contribute to a better knowledge of the biology of this orchid as well as of other sympatric Patagonian orchid species, all of them currently under serious risk of extinction. PMID:24777596

  7. Perspectives on MADS-box expression during orchid flower evolution and development

    PubMed Central

    Mondragón-Palomino, Mariana

    2013-01-01

    The diverse morphology of orchid flowers and their complex, often deceptive strategies to become pollinated have fascinated researchers for a long time. However, it was not until the 20th century that the ontogeny of orchid flowers, the genetic basis of their morphology and the complex phylogeny of Orchidaceae were investigated. In parallel, the improvement of techniques for in vitro seed germination and tissue culture, together with studies on biochemistry, physiology, and cytology supported the progress of what is now a highly productive industry of orchid breeding and propagation. In the present century both basic research in orchid flower evo-devo and the interest for generating novel horticultural varieties have driven the characterization of many members of the MADS-box family encoding key regulators of flower development. This perspective summarizes the picture emerging from these studies and discusses the advantages and limitations of the comparative strategy employed so far. I address the growing role of natural and horticultural mutants in these studies and the emergence of several model species in orchid evo-devo and genomics. In this context, I make a plea for an increasingly integrative approach. PMID:24065980

  8. Independent recruitment of saprotrophic fungi as mycorrhizal partners by tropical achlorophyllous orchids.

    PubMed

    Martos, Florent; Dulormne, Maguy; Pailler, Thierry; Bonfante, Paola; Faccio, Antonella; Fournel, Jacques; Dubois, Marie-Pierre; Selosse, Marc-André

    2009-11-01

    Mycoheterotrophic orchids have adapted to shaded forest understory by shifting to achlorophylly and receiving carbon from their mycorrhizal fungi. In temperate forests, they associate in a highly specific way with fungi forming ectomycorrhizas on nearby trees, and exploiting tree photosynthates. However, many rainforests lack ectomycorrhizal fungi, and there is evidence that some tropical Asiatic species associate with saprotrophic fungi. To investigate this in different geographic and phylogenetic contexts, we identified the mycorrhizal fungi supporting two tropical mycoheterotrophic orchids from Mascarene (Indian Ocean) and Caribbean islands. We tested their possible carbon sources by measuring natural nitrogen ((15)N) and carbon ((13)C) abundances. Saprotrophic basidiomycetes were found: Gastrodia similis associates with a wood-decaying Resinicium (Hymenochaetales); Wullschlaegelia aphylla associates with both litter-decaying Gymnopus and Mycena species, whose rhizomorphs link orchid roots to leaf litter. The (15)N and (13)C abundances make plausible food chains from dead wood to G. similis and from dead leaves to W. aphylla. We propose that temperature and moisture in rainforests, but not in most temperate forests, may favour sufficient saprotrophic activity to support development of mycoheterotrophs. By enlarging the spectrum of mycorrhizal fungi and the level of specificity in mycoheterotrophic orchids, this study provides new insights on orchid and mycorrhizal biology in the tropics. PMID:19694964

  9. Types of Pollen Dispersal Units in Orchids, and their Consequences for Germination and Fertilization

    PubMed Central

    Pacini, Ettore; Hesse, Michael

    2002-01-01

    The various pollen dispersal units (PDU) found in orchids are discussed together with possible evolutionary trends and the consequences for germination and fertilization. Orchids with monad and tetrad pollen form more complex dispersal units by means of pollenkitt, elastoviscin, a callosic wall, common walls or a combination of these. Evolutionary trends include (1) from pollenkitt to elastoviscin; (2) from monad to tetrads and multiples of tetrads; (3) from partially dehydrated (<30 %) to partially hydrated (>30 %) pollen; and (4) from monad pollen to PDUs with many pollen grains. The biological consequences concern both male and female reproductive systems. Some features of the male side are present in all orchids irrespective of the pollen dispersal unit, whereas other characters are found only in orchids with pollinia; the same applies for the female counterpart. Pollen grains of orchids with pollinia germinate at least 24 h after pollination because the pollen grains/tetrads must swell and make space for the growth of pollen tubes. PMID:12102520

  10. Changes in Orchid Bee Communities Across Forest-Agroecosystem Boundaries in Brazilian Atlantic Forest Landscapes.

    PubMed

    De Aguiar, Willian Moura; Sofia, Silvia H; Melo, Gabriel A R; Gaglianone, Maria Cristina

    2015-12-01

    Deforestation has dramatically reduced the extent of Atlantic Forest cover in Brazil. Orchid bees are key pollinators in neotropical forest, and many species are sensitive to anthropogenic interference. In this sense understanding the matrix permeability for these bees is important for maintaining genetic diversity and pollination services. Our main objective was to assess whether the composition, abundance, and diversity of orchid bees in matrices differed from those in Atlantic forest. To do this we sampled orchid bees at 4-mo intervals from 2007 to 2009 in remnants of Atlantic Forest, and in the surrounding pasture and eucalyptus matrices. The abundance, richness, and diversity of orchid bees diminished significantly from the forest fragment toward the matrix points in the eucalyptus and pasture. Some common or intermediate species in the forest areas, such as Eulaema cingulata (F.) and Euglossa fimbriata Moure, respectively, become rare species in the matrices. Our results show that the orchid bee community is affected by the matrices surrounding the forest fragments. They also suggest that connections between forest fragments need to be improved using friendly matrices that can provide more favorable conditions for bees and increase their dispersal between fragments. PMID:26314032

  11. A bibenzyl from Dendrobium ellipsophyllum inhibits migration in lung cancer cells.

    PubMed

    Chaotham, Chatchai; Chanvorachote, Pithi

    2015-10-01

    Metastatic cancer cells have been shown to have aggressive behaviors accounting for the high incidence of chemotherapeutic failure and mortality. Because migration and invasion are crucial behaviors for cancer cell dissemination, promising compounds exhibiting potential antimigration effects are of interest for metastasis-based therapeutic approaches. This study aimed to evaluate the activity of a bibenzyl, 4,5,4'-trihydroxy-3,3'-dimethoxybibenzyl (TDB), isolated from Dendrobium ellipsophyllum Tang and Wang, in the suppression of migration in human lung cancer cells. TDB at nontoxic concentrations (1 and 5 µM) significantly inhibited the motility of lung cancer cells in scratch-wound assay. Chemotaxis-induced migration and invasion assays also revealed that the cell motility dramatically diminished in the cells treated with 1-5 µM TDB. Western blot analysis provided the underlying molecular mechanism, showing that TDB reduced such cell migration and invasion by decreasing migration-regulating proteins, including integrins αv, α4, β1, β3 and β5, as well as downstream signaling proteins, such as activated focal adhesion kinase (pFAK), activated Ras-related C3 botulinum toxin substrate 1 (Rac1-GTP) and cell division control protein 42 (Cdc42). As the presence of cellular protrusion, called filopodia, has been indicated as a hallmark of migrating cells, we showed that the reduction of the mentioned proteins correlated well with the disappearance of filopodia. In summary, this study demonstrates the promising activity of TDB and its mechanism in the inhibition of lung cancer cell migration, which might be useful for encouraging the development of this compound for antimetastatic approaches. PMID:26109451

  12. Daldionin, an Unprecedented Binaphthyl Derivative, and Diverse Polyketide Congeners from a Fungal Orchid Endophyte.

    PubMed

    Barnes, Emma C; Jumpathong, Juangjun; Lumyong, Saisamorn; Voigt, Kerstin; Hertweck, Christian

    2016-03-18

    Thailand possesses a rich diversity of orchid species that, in turn, live in symbiosis with a wide variety of fungi. Such endophytes have the potential to produce secondary metabolites with bioactivity against orchid and/or human pathogens. The orchid-associated fungal strain Daldinia eschscholtzii was found to produce a diverse range of aromatic polyketides including the new naphthalene derivatives daldionin, nodulones B and C, and daldinones F and G along with eight known compounds. Daldionin possesses an unprecedented oxane-linked binaphthyl ring system. These compounds demonstrate the high diversity of structural variations that are constructed during fungal biosynthesis, and the results include important observations concerning the biosynthesis of binaphthyl derivatives. Daldionin was found to have weak antiproliferative activity against HUVEC and K-562 cell lines. All but one of the isolated compounds showed moderate antimicrobial activity towards at least one of the four tested microbial strains. PMID:26880363

  13. Conservation Value and Permeability of Neotropical Oil Palm Landscapes for Orchid Bees

    PubMed Central

    Livingston, George; Jha, Shalene; Vega, Andres; Gilbert, Lawrence

    2013-01-01

    The proliferation of oil palm plantations has led to dramatic changes in tropical landscapes across the globe. However, relatively little is known about the effects of oil palm expansion on biodiversity, especially in key ecosystem-service providing organisms like pollinators. Rapid land use change is exacerbated by limited knowledge of the mechanisms causing biodiversity decline in the tropics, particularly those involving landscape features. We examined these mechanisms by undertaking a survey of orchid bees, a well-known group of Neotropical pollinators, across forest and oil palm plantations in Costa Rica. We used chemical baits to survey the community in four regions: continuous forest sites, oil palm sites immediately adjacent to forest, oil palm sites 2km from forest, and oil palm sites greater than 5km from forest. We found that although orchid bees are present in all environments, orchid bee communities diverged across the gradient, and community richness, abundance, and similarity to forest declined as distance from forest increased. In addition, mean phylogenetic distance of the orchid bee community declined and was more clustered in oil palm. Community traits also differed with individuals in oil palm having shorter average tongue length and larger average geographic range size than those in the forest. Our results indicate two key features about Neotropical landscapes that contain oil palm: 1) oil palm is selectively permeable to orchid bees and 2) orchid bee communities in oil palm have distinct phylogenetic and trait structure compared to communities in forest. These results suggest that conservation and management efforts in oil palm-cultivating regions should focus on landscape features. PMID:24147137

  14. Are carbon and nitrogen exchange between fungi and the orchid Goodyera repens affected by irradiance?

    PubMed Central

    Liebel, Heiko T.; Bidartondo, Martin I.; Gebauer, Gerhard

    2015-01-01

    Background and Aims The green orchid Goodyera repens has been shown to transfer carbon to its mycorrhizal partner, and this flux may therefore be affected by light availability. This study aimed to test whether the C and N exchange between plant and fungus is dependent on light availability, and in addition addressed the question of whether flowering and/or fruiting individuals of G. repens compensate for changes in leaf chlorophyll concentration with changes in C and N flows from fungus to plant. Methods The natural abundances of stable isotopes of plant C and N were used to infer changes in fluxes between orchid and fungus across natural gradients of irradiance at five sites. Mycorrhizal fungi in the roots of G. repens were identified by molecular analyses. Chlorophyll concentrations in the leaves of the orchid and of reference plants were measured directly in the field. Key Results Leaf δ13C values of G. repens responded to changes in light availability in a similar manner to autotrophic reference plants, and different mycorrhizal fungal associations also did not affect the isotope abundance patterns of the orchid. Flowering/fruiting individuals had lower leaf total N and chlorophyll concentrations, which is most probably explained by N investments to form flowers, seeds and shoot. Conclusions The results indicate that mycorrhizal physiology is relatively fixed in G. repens, and changes in the amount and direction of C flow between plant and fungus were not observed to depend on light availability. The orchid may instead react to low-light sites through increased clonal growth. The orchid does not compensate for low leaf total N and chlorophyll concentrations by using a 13C- and 15N-enriched fungal source. PMID:25538109

  15. Conservation value and permeability of neotropical oil palm landscapes for orchid bees.

    PubMed

    Livingston, George; Jha, Shalene; Vega, Andres; Gilbert, Lawrence

    2013-01-01

    The proliferation of oil palm plantations has led to dramatic changes in tropical landscapes across the globe. However, relatively little is known about the effects of oil palm expansion on biodiversity, especially in key ecosystem-service providing organisms like pollinators. Rapid land use change is exacerbated by limited knowledge of the mechanisms causing biodiversity decline in the tropics, particularly those involving landscape features. We examined these mechanisms by undertaking a survey of orchid bees, a well-known group of Neotropical pollinators, across forest and oil palm plantations in Costa Rica. We used chemical baits to survey the community in four regions: continuous forest sites, oil palm sites immediately adjacent to forest, oil palm sites 2 km from forest, and oil palm sites greater than 5 km from forest. We found that although orchid bees are present in all environments, orchid bee communities diverged across the gradient, and community richness, abundance, and similarity to forest declined as distance from forest increased. In addition, mean phylogenetic distance of the orchid bee community declined and was more clustered in oil palm. Community traits also differed with individuals in oil palm having shorter average tongue length and larger average geographic range size than those in the forest. Our results indicate two key features about Neotropical landscapes that contain oil palm: 1) oil palm is selectively permeable to orchid bees and 2) orchid bee communities in oil palm have distinct phylogenetic and trait structure compared to communities in forest. These results suggest that conservation and management efforts in oil palm-cultivating regions should focus on landscape features. PMID:24147137

  16. Stable Epigenetic Effects Impact Adaptation in Allopolyploid Orchids (Dactylorhiza: Orchidaceae)

    PubMed Central

    Paun, Ovidiu; Bateman, Richard M.; Fay, Michael F.; Hedrén, Mikael; Civeyrel, Laure; Chase, Mark W.

    2010-01-01

    Epigenetic information includes heritable signals that modulate gene expression but are not encoded in the primary nucleotide sequence. We have studied natural epigenetic variation in three allotetraploid sibling orchid species (Dactylorhiza majalis s.str, D. traunsteineri s.l., and D. ebudensis) that differ radically in geography/ecology. The epigenetic variation released by genome doubling has been restructured in species-specific patterns that reflect their recent evolutionary history and have an impact on their ecology and evolution, hundreds of generations after their formation. Using two contrasting approaches that yielded largely congruent results, epigenome scans pinpointed epiloci under divergent selection that correlate with eco-environmental variables, mainly related to water availability and temperature. The stable epigenetic divergence in this group is largely responsible for persistent ecological differences, which then set the stage for species-specific genetic patterns to accumulate in response to further selection and/or drift. Our results strongly suggest a need to expand our current evolutionary framework to encompass a complementary epigenetic dimension when seeking to understand population processes that drive phenotypic evolution and adaptation. PMID:20551043

  17. Micropropagation of terrestrial orchids, Anoectochilus sikkimensis and Anoectochilus regalis.

    PubMed

    Gangaprasad, A; Latha, P G; Seeni, S

    2000-02-01

    Two horticulturally important jewel orchids of the genus Anoectochilus were successfully micropropagated. Isolated nodes of A. sikkimensis collected from Sikkim in Eastern Himalayas and subsequently reared under nursery conditions and A. regalis collected from Western Ghats in Southern India were cultured for 12 weeks on Woody Plant Medium (WPM) to produce a maximum of 4.8 and 5.6 callus--free axillary shoots respectively at 95 and 98% efficiency. During reculture of the explants from in vitro raised shoots under the same conditions, the total number of shoots obtained from the nodes (21.4) and shoot tips (8.2) of A. regalis were significantly higher than those hardy and slow growing shoots of A. sikkimensis (12.3 and 4.3) respectively. Shoots (4-6 cm) were rooted in medium containing NAA (2.70 microM) and activated charcoal (0.2%). The rooted plants established at 95-98% rate in community pots after hardening. After 6 months, green house adapted community potted plants of A. regalis were transferred to natural forest habitat locally with 95 and 70% survival respectively after 12 months. The plants, established in community pots and native forest habitat were free from any morphological and growth defects. PMID:11218831

  18. Hydrothermal synthesis and characterization of orchid-like MnO 2 nanostructures

    NASA Astrophysics Data System (ADS)

    Li, Xueliang; Li, Wenjie; Chen, Xiangying; Shi, Chengwu

    2006-12-01

    Orchid-like Cr-doped MnO 2 nanostructures have been synthesized via a hydrothermal method, using KClO 3 as the oxidant. The as-obtained samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectra (XPS), transmission electron microscopy (TEM) and field emission scanning electron microscopy (FE-SEM). Results show that the morphologies of orchid-like MnO 2 are made up of nanorods. The influences of chromium in the solution on the morphology of the products are discussed. The electrochemical characterization was carried out by cyclic voltammetry, which indicated that the products were excellent electrode material for super-capacitor.

  19. [Orchids from coffee-plantations in mexico: an alternative for the sustainable use of tropical ecosystems].

    PubMed

    Espejo Sema, Adolfo; López-Ferrari, Ana Rosa; Jiménez Machorro, Rolando; Sánchez Saldaña, Luis

    2005-01-01

    Life form, endemism, conservation status, and horticultural interest are detailed for orchid species associated to shade coffee-plantations in Mexico. About 11% of the orchid taxa (214 species) found in these agroecosystems are in the Mexican list of species requiring some form of protection. Almost 40% of the species are of horticultural interest. The importance of promoting shaded coffee plantations as an alternative to the conservation of primary plant communities in Mexican and other tropical regions is clear. Long term management plans are recommended. PMID:17354421

  20. Isolation and characterization of microsatellite loci in Epidendrum puniceoluteum, an endemic orchid from the Atlantic Rainforest.

    PubMed

    Pinheiro, F; Santos, M O; Palma-Silva, C; Barros, F; Meyer, D; Salatino, A; Souza, A P; Cozzolino, S

    2008-09-01

    Epidendrum puniceoluteum is an endemic orchid of Atlantic Rainforest, restricted to few populations only due to the destruction and fragmentation of its native habitat. Here, we report on the development of 10 microsatellite markers isolated from this orchid species. Genetic variability was characterized in two distant populations from Brazil coast. The number of alleles observed for each locus ranged from two to 12 and with an average of 6.4 alleles per locus. These microsatellites should be valuable tools for studying both fine-scale genetic structure of scattered E. puniceoluteum population and patterns will be useful genetic markers for other closely related taxa. PMID:21585988

  1. Atractiellomycetes belonging to the ‘rust’ lineage (Pucciniomycotina) form mycorrhizae with terrestrial and epiphytic neotropical orchids

    PubMed Central

    Kottke, Ingrid; Suárez, Juan Pablo; Herrera, Paulo; Cruz, Dario; Bauer, Robert; Haug, Ingeborg; Garnica, Sigisfredo

    2010-01-01

    Distinctive groups of fungi are involved in the diverse mycorrhizal associations of land plants. All previously known mycorrhiza-forming Basidiomycota associated with trees, ericads, liverworts or orchids are hosted in Agaricomycetes, Agaricomycotina. Here we demonstrate for the first time that Atractiellomycetes, members of the ‘rust’ lineage (Pucciniomycotina), are mycobionts of orchids. The mycobionts of 103 terrestrial and epiphytic orchid individuals, sampled in the tropical mountain rainforest of Southern Ecuador, were identified by sequencing the whole ITS1-5.8S-ITS2 region and part of 28S rDNA. Mycorrhizae of 13 orchid individuals were investigated by transmission electron microscopy. Simple septal pores and symplechosomes in the hyphal coils of mycorrhizae from four orchid individuals indicated members of Atractiellomycetes. Molecular phylogeny of sequences from mycobionts of 32 orchid individuals out of 103 samples confirmed Atractiellomycetes and the placement in Pucciniomycotina, previously known to comprise only parasitic and saprophytic fungi. Thus, our finding reveals these fungi, frequently associated to neotropical orchids, as the most basal living basidiomycetes involved in mycorrhizal associations of land plants. PMID:20007181

  2. Stable isotope signatures confirm carbon and nitrogen gain through ectomycorrhizas in the ghost orchid Epipogium aphyllum Swartz.

    PubMed

    Liebel, H T; Gebauer, G

    2011-03-01

    Epipogium aphyllum is a rare Eurasian achlorophyllous forest orchid known to associate with fungi that form ectomycorrhizas, while closely related orchids of warm humid climates depend on wood- or litter-decomposer fungi. We conducted (13) C and (15) N stable isotope natural abundance analyses to identify the organic nutrient source of E. aphyllum from Central Norway. These data for orchid shoot tissues, in comparison to accompanying autotrophic plants, document C and N flow from ectomycorrhizal fungi to the orchid. DNA data from fungal pelotons in the orchid root cortex confirm the presence of Inocybe and Hebeloma, which are both fungi that form ectomycorrhizas. The enrichment factors for (13) C and (15) N of E. aphyllum are used to calculate a new overall average enrichment factor for mycoheterotrophic plants living in association with ectomycorrhizal fungi (ε(13) C ± 1 SD of 7.2 ± 1.6 ‰ and ε(15) N ± 1 SD of 12.8 ± 3.9 ‰). These can be used to estimate the fungal contribution to organic nutrient uptake by partially mycoheterotrophic plants where fully mycoheterotrophic plants are lacking. N concentrations in orchid tissue were unusually high and significantly higher than in accompanying autotrophic leaf samples. This may be caused by N gain of E. aphyllum from obligate ectomycorrhizal fungi. We show that E. aphyllum is an epiparasitic mycoheterotrophic orchid that depends on ectomycorrhizal Inocybe and Hebeloma to obtain C and N through a tripartite system linking mycoheterotrophic plants through fungi with forest trees. PMID:21309973

  3. Population dynamics of epiphytic orchids in a metapopulation context

    PubMed Central

    Winkler, Manuela; Hülber, Karl; Hietz, Peter

    2009-01-01

    Background and Aims Populations of many epiphytes show a patchy distribution where clusters of plants growing on individual trees are spatially separated and may thus function as metapopulations. Seed dispersal is necessary to (re)colonize unoccupied habitats, and to transfer seeds from high- to low-competition patches. Increasing dispersal distances, however, reduces local fecundity and the probability that seeds will find a safe site outside the original patch. Thus, there is a conflict between seed survival and colonization. Methods Populations of three epiphytic orchids were monitored over three years in a Mexican humid montane forest and analysed with spatially averaged and with spatially explicit matrix metapopulation models. In the latter, population dynamics at the scale of the subpopulations (epiphytes on individual host trees) are based on detailed stage-structured observations of transition probabilities and trees are connected by a dispersal function. Key Results Population growth rates differed among trees and years. While ignoring these differences, and averaging the population matrices over trees, yields negative population growth, metapopulation models predict stable or growing populations because the trees that support growing subpopulations determine the growth of the metapopulation. Stochastic models which account for the differences among years differed only marginally from deterministic models. Population growth rates were significantly lower, and extinctions of local patches more frequent in models where higher dispersal results in reduced local fecundity compared with hypothetical models where this is not the case. The difference between the two models increased with increasing mean dispersal distance. Though recolonization events increased with dispersal distance, this could not compensate the losses due to reduced local fecundity. Conclusions For epiphytes, metapopulation models are useful to capture processes beyond the level of the single

  4. Genome size diversity in orchids: consequences and evolution

    PubMed Central

    Leitch, I. J.; Kahandawala, I.; Suda, J.; Hanson, L.; Ingrouille, M. J.; Chase, M. W.; Fay, M. F.

    2009-01-01

    Background The amount of DNA comprising the genome of an organism (its genome size) varies a remarkable 40 000-fold across eukaryotes, yet most groups are characterized by much narrower ranges (e.g. 14-fold in gymnosperms, 3- to 4-fold in mammals). Angiosperms stand out as one of the most variable groups with genome sizes varying nearly 2000-fold. Nevertheless within angiosperms the majority of families are characterized by genomes which are small and vary little. Species with large genomes are mostly restricted to a few monocots families including Orchidaceae. Scope A survey of the literature revealed that genome size data for Orchidaceae are comparatively rare representing just 327 species. Nevertheless they reveal that Orchidaceae are currently the most variable angiosperm family with genome sizes ranging 168-fold (1C = 0·33–55·4 pg). Analysing the data provided insights into the distribution, evolution and possible consequences to the plant of this genome size diversity. Conclusions Superimposing the data onto the increasingly robust phylogenetic tree of Orchidaceae revealed how different subfamilies were characterized by distinct genome size profiles. Epidendroideae possessed the greatest range of genome sizes, although the majority of species had small genomes. In contrast, the largest genomes were found in subfamilies Cypripedioideae and Vanilloideae. Genome size evolution within this subfamily was analysed as this is the only one with reasonable representation of data. This approach highlighted striking differences in genome size and karyotype evolution between the closely related Cypripedium, Paphiopedilum and Phragmipedium. As to the consequences of genome size diversity, various studies revealed that this has both practical (e.g. application of genetic fingerprinting techniques) and biological consequences (e.g. affecting where and when an orchid may grow) and emphasizes the importance of obtaining further genome size data given the considerable

  5. Floral adaptation to local pollinator guilds in a terrestrial orchid

    PubMed Central

    Sun, Mimi; Gross, Karin; Schiestl, Florian P.

    2014-01-01

    Background and Aims Studies of local floral adaptation in response to geographically divergent pollinators are essential for understanding floral evolution. This study investigated local pollinator adaptation and variation in floral traits in the rewarding orchid Gymnadenia odoratissima, which spans a large altitudinal gradient and thus may depend on different pollinator guilds along this gradient. Methods Pollinator communities were assessed and reciprocal transfer experiments were performed between lowland and mountain populations. Differences in floral traits were characterized by measuring floral morphology traits, scent composition, colour and nectar sugar content in lowland and mountain populations. Key Results The composition of pollinator communities differed considerably between lowland and mountain populations; flies were only found as pollinators in mountain populations. The reciprocal transfer experiments showed that when lowland plants were transferred to mountain habitats, their reproductive success did not change significantly. However, when mountain plants were moved to the lowlands, their reproductive success decreased significantly. Transfers between populations of the same altitude did not lead to significant changes in reproductive success, disproving the potential for population-specific adaptations. Flower size of lowland plants was greater than for mountain flowers. Lowland plants also had significantly higher relative amounts of aromatic floral volatiles, while the mountain plants had higher relative amounts of other floral volatiles. The floral colour of mountain flowers was significantly lighter compared with the lowland flowers. Conclusions Local pollinator adaptation through pollinator attraction was shown in the mountain populations, possibly due to adaptation to pollinating flies. The mountain plants were also observed to receive pollination from a greater diversity of pollinators than the lowland plants. The different floral

  6. Element-tracing of mineral matters in Dendrobium officinale using ICP-MS and multivariate analysis.

    PubMed

    Zhu, Nannan; Han, Shen; Yang, Chunning; Qu, Jixu; Sun, Zhirong; Liu, Wenjie; Zhang, Xiaomin

    2016-01-01

    Rare studies have been performed to trace the mineral elements in Dendrobium officinale. In this study, we aim to trace the mineral elements in D. officinale collected from ten geographical locations in China. ICP-MS system was used for simultaneous determination of mineral elements. Principal component analysis was performed using the obtained data in the quantification of mineral contents. Cluster analysis was performed using the Ward's method. Several of essential microelments were detected in D. officinale, including ferrum (Fe), manganese (Mn), zinc (Zn), chromium (Cr), nickel (Ni) and vanadium (V). Among these elements, three elements (i.e. Fe, Mn and Zn) were highly and simultaneously detected in the D. officinale collected from the ten locations. The level of Ni was positively associated with that of Zn (r = 0.986, P < 0.01). The level of titanium (Ti) was positively associated with that of V (r = 0.669, P < 0.05), and negatively associated with Cr (r = -0.710, P < 0.05). In addition, the level of Mn was positively associated with that of barium (r = 0.749, P < 0.05). Further, the level of Fe was positively associated with that of Ni (r = 0.664, P < 0.05), Zn (r = 0.742, P < 0.05), and rare earth elements (r = 0.847, P < 0.01), respectively. Three eigenvalues explained about 86.60 % of the total variance, which contributed significantly to the explanation of cumulative variance. Cluster analysis indicated the cultivars were categorized into 3 clusters. Ni, Zn, Fe, Cr, Ti and rare earth elements were designated as the characteristic elements. Cultivars collected from Yulin, Menghai, and Shaoguan ranked the top 3 in the comprehensive scores, indicating the content of the mineral elements was comparatively higher in these locations. PMID:27429889

  7. Occurrence of Bacillus amyloliquefaciens as a systemic endophyte of vanilla orchids.

    PubMed

    White, James F; Torres, Mónica S; Sullivan, Raymond F; Jabbour, Rabih E; Chen, Qiang; Tadych, Mariusz; Irizarry, Ivelisse; Bergen, Marshall S; Havkin-Frenkel, Daphna; Belanger, Faith C

    2014-11-01

    We report the occurrence of Bacillus amyloliquefaciens in vanilla orchids (Vanilla phaeantha) and cultivated hybrid vanilla (V. planifolia × V. pompona) as a systemic bacterial endophyte. We determined with light microscopy and isolations that tissues of V. phaeantha and the cultivated hybrid were infected by a bacterial endophyte and that shoot meristems and stomatal areas of stems and leaves were densely colonized. We identified the endophyte as B. amyloliquefaciens using DNA sequence data. Since additional endophyte-free plants and seed of this orchid were not available, additional studies were performed on surrogate hosts Amaranthus caudatus, Ipomoea tricolor, and I. purpurea. Plants of A. caudatus inoculated with B. amyloliquefaciens demonstrated intracellular colonization of guard cells and other epidermal cells, confirming the pattern observed in the orchids. Isolations and histological studies suggest that the bacterium may penetrate deeply into developing plant tissues in shoot meristems, forming endospores in maturing tissues. B. amyloliquefaciens produced fungal inhibitors in culture. In controlled experiments using morning glory seedlings we showed that the bacterium promoted seedling growth and reduced seedling necrosis due to pathogens. We detected the gene for phosphopantetheinyl transferase (sfp), an enzyme in the pathway for production of antifungal lipopeptides, and purified the lipopeptide "surfactin" from cultures of the bacterium. We hypothesize that B. amyloliquefaciens is a robust endophyte and defensive mutualist of vanilla orchids. Whether the symbiosis between this bacterium and its hosts can be managed to protect vanilla crops from diseases is a question that should be evaluated in future research. PMID:25060609

  8. Naturalized orchid bee pollinates resin reward flowers in Florida: novel and known mutualism.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Females of an orchid bee, Euglossa viridissima, recently naturalized in southern Florida, routinely collect resin to construct their brood cells from the flowers of two Clusia and two Dalechampia species. The bee pollinates three of these species including: 1) the newly naturalized D. scandens, whic...

  9. ORCHID - a computer simulation of the reliability of an NDE inspection system

    SciTech Connect

    Moles, M.D.C.

    1987-03-01

    CANDU pressurized heavy water reactors contain several hundred horizontally-mounted zirconium alloy pressure tubes. Following a pressure tube failure, a pressure tube inspection system called CIGARette was rapidly designed, manufactured and put in operation. Defects called hydride blisters were found to be the cause of the failure, and were detected using a combination of eddy current and ultrasonic scans. A number of improvements were made to CIGARette during the inspection period. The ORCHID computer program models the operation of the delivery system, eddy current and ultrasonic systems by imitating the on-reactor decision-making procedure. ORCHID predicts that during the early stage of development, less than one blistered tube in three would be detected, while less than one in two would be detected in the middle development stage. However, ORCHID predicts that during the late development stage, probability of detection will be over 90%, primarily due to the inclusion of axial ultrasonic scans (a procedural modification). Rotational and axial slip could severely reduce probability of detection. Comparison of CIGARette's inspection data with ORCHID's predictions indicate that the latter are compatible with the actual inspection results, through the numbers are small and data uncertain. It should be emphasized that the CIGARette system has been essentially replaced with the much more reliable CIGAR system.

  10. Pollinator Behaviour on a Food-Deceptive Orchid Calypso bulbosa and Coflowering Species

    PubMed Central

    Tuomi, Juha; Lämsä, Juho; Wannas, Lauri; Abeli, Thomas; Jäkäläniemi, Anne

    2015-01-01

    Food deception as a pollination strategy has inspired many studies over the last few decades. Pollinator deception has evolved in many orchids possibly to enhance outcrossing. Food-deceptive orchids usually have low pollinator visitation rates as compared to rewarding species. They may benefit in visitations from the presence (magnet-species hypothesis) or, alternatively, absence of coflowering rewarding species (competition hypothesis). We present data on pollinator visitations on a deceptive, terrestrial orchid Calypso bulbosa, a species with a single flower per plant and whose flowering period partly overlaps with rewarding, early flowering willows (Salix sp.) and later-flowering bilberry (Vaccinium myrtillus). When surveying inactive bumblebee queens on willows in cool weather, about 7% of them carried Calypso pollinia. Most common bumblebee species appeared to visit and thus pollinate Calypso. Bumblebees typically visited one to three Calypso flowers before flying away, providing some support for the outcrossing hypothesis. We conclude that, regarding the pollinations strategy, both magnet-species and competition hypotheses have a role in the pollination of Calypso, but on different spatial scales. On a large scale rewarding species are important for attracting pollinators to a given region, but on a small scale absence of competition ensures sufficient pollination rate for the deceptive orchid. PMID:25861675

  11. Conservation Genetics of an Endangered Lady’s Slipper Orchid: Cypripedium japonicum in China

    PubMed Central

    Qian, Xin; Li, Quan-Jian; Liu, Fen; Gong, Mao-Jiang; Wang, Cai-Xia; Tian, Min

    2014-01-01

    Knowledge about the population genetic variation of the endangered orchid, Cypripedium japonicum, is conducive to the development of conservation strategies. Here, we examined the levels and partitioning of inter-simple sequence repeat (ISSR) diversity (109 loci) in five populations of this orchid to gain insight into its genetic variation and population structure in Eastern and Central China. It harbored considerably lower levels of genetic diversity both at the population (percentage of polymorphic loci (PPL) = 11.19%, Nei’s gene diversity (H) = 0.0416 and Shannon’s information index (I) = 0.0613) and species level (PPL = 38.53%, H = 0.1273 and I = 0.1928) and a significantly higher degree of differentiation among populations (the proportion of the total variance among populations (Φpt) = 0.698) than those typical of ISSR-based studies in other orchid species. Furthermore, the Nei’s genetic distances between populations were independent of the corresponding geographical distances. Two main clusters are shown in an arithmetic average (UPGMA) dendrogram, which is in agreement with the results of principal coordinate analysis (PCoA) analysis and the STRUCTURE program. In addition, individuals within a population were more similar to each other than to those in other populations. Based on the genetic data and our field survey, the development of conservation management for this threatened orchid should include habitat protection, artificial gene flow and ex situ measures. PMID:24983476

  12. Genome Assembly of Citrus Leprosis Virus Nuclear Type Reveals a Close Association with Orchid Fleck Virus

    PubMed Central

    Stone, Andrew; Otero-Colina, Gabriel; Wei, Gang; Choudhary, Nandlal; Achor, Diann; Shao, Jonathan; Levy, Laurene; Nakhla, Mark K.; Hollingsworth, Charla R.; Hartung, John S.; Schneider, William L.

    2013-01-01

    The complete genome of citrus leprosis virus nuclear type (CiLV-N) was identified by small RNA sequencing utilizing leprosis-affected citrus samples collected from the state of Querétaro, Mexico. The nucleotide identity and phylogenetic analysis indicate that CiLV-N is very closely related to orchid fleck virus, which typically infects Cymbidium species. PMID:23887919

  13. Integrative taxonomy of the fly orchid group: insights from chemical ecology.

    PubMed

    Joffard, Nina; Buatois, Bruno; Schatz, Bertrand

    2016-10-01

    Several authors have recently stressed the need to develop an integrative approach in taxonomy, but studies applying such an approach to Mediterranean orchids are scarce. In sexually deceptive orchids from the taxonomically difficult genus Ophrys, pollination is specific and performed by male insects attracted to the flowers by sex pheromone-mimicking floral scents. Floral compounds are therefore of primary importance for reproductive isolation and species delimitations in this genus. In the fly orchid group, molecular, morphological, and ecological characters have been extensively studied, but a comprehensive survey of floral scents is still lacking. In the present study, the blends of floral compounds of its three members, Ophrys insectifera, Ophrys aymoninii, and Ophrys subinsectifera, were extracted and analyzed by gas chromatography-mass spectrometry. A total of 107 compounds were found, with a majority of saturated and unsaturated hydrocarbons. Significant differentiation, both qualitative and quantitative, was found among the three taxa. This result, pooled with those from the literature, forms a comprehensive and congruent dataset that allows us to elucidate the taxonomic rank of the three members of the fly orchid group. PMID:27614455

  14. A tale of two orchids: comparative reproductive development in Vanilla and Phalaenopsis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The orchid family of flowering plants (Orchidaceae) represents the largest, most diverse, and most successful family of flowering plants in the world yet they are one of the most understudied groups from a molecular and genomic perspective. To further the long-term goal of developing enabling genom...

  15. Estimating the extent and structure of trade in horticultural orchids via social media.

    PubMed

    Hinsley, Amy; Lee, Tamsin E; Harrison, Joseph R; Roberts, David L

    2016-10-01

    The wildlife trade is a lucrative industry involving thousands of animal and plant species. The increasing use of the internet for both legal and illegal wildlife trade is well documented, but there is evidence that trade may be emerging on new online technologies such as social media. Using the orchid trade as a case study, we conducted the first systematic survey of wildlife trade on an international social-media website. We focused on themed forums (groups), where people with similar interests can interact by uploading images or text (posts) that are visible to other group members. We used social-network analysis to examine the ties between 150 of these orchid-themed groups to determine the structure of the network. We found 4 communities of closely linked groups based around shared language. Most trade occurred in a community that consisted of English-speaking and Southeast Asian groups. In addition to the network analysis, we randomly sampled 30 groups from the whole network to assess the prevalence of trade in cultivated and wild plants. Of 55,805 posts recorded over 12 weeks, 8.9% contained plants for sale, and 22-46% of these posts pertained to wild-collected orchids. Although total numbers of posts about trade were relatively small, the large proportion of posts advertising wild orchids for sale supports calls for better monitoring of social media for trade in wild-collected plants. PMID:26991837

  16. Ectomycorrhizal Inocybe species associate with the mycoheterotrophic orchid Epipogium aphyllum but not its asexual propagules

    PubMed Central

    Roy, Melanie; Yagame, Takahiro; Yamato, Masahide; Iwase, Koji; Heinz, Christine; Faccio, Antonella; Bonfante, Paola; Selosse, Marc-Andre

    2009-01-01

    Background and Aims Epipogium aphyllum is a Eurasian achlorophyllous, mycoheterotrophic forest orchid. Due to its rarity, it is often protected, and its biology is poorly known. The identity and pattern of colonization of fungal associates providing carbon to this orchid have not been studied previously. Methods Using samples from 34 individuals from 18 populations in Japan, Russia and France, the following were investigated: (a) colonization patterns of fungal associates of E. aphyllum by microscopy; (b) their identity by PCR amplification of nuclear ribosomal ITS carried out on rhizome fragments and hyphal pelotons. Results and Conclusions Microscopic investigations revealed that thick rhizomes were densely colonized by fungi bearing clamp-connections and dolipores, i.e. basidiomycetes. Molecular analysis identified Inocybe species as exclusive symbionts of 75 % of the plants investigated and, more rarely, other basidiomycetes (Hebeloma, Xerocomus, Lactarius, Thelephora species). Additionally, ascomycetes, probably endophytes or parasites, were sometimes present. Although E. aphyllum associates with diverse species from Inocybe subgenera Mallocybe and Inocybe sensu stricto, no evidence for cryptic speciation in E. aphyllum was found. Since basidiomycetes colonizing the orchid are ectomycorrhizal, surrounding trees are probably the ultimate carbon source. Accordingly, in one population, ectomycorrhizae sampled around an individual orchid revealed the same fungus on 11·2 % of tree roots investigated. Conversely, long, thin stolons bearing bulbils indicated active asexual multiplication, but these propagules were not colonized by fungi. These findings are discussed in the framework of ecology and evolution of mycoheterotrophy. PMID:19155220

  17. Convergent evolution of floral signals underlies the success of Neotropical orchids

    PubMed Central

    Papadopulos, Alexander S. T.; Powell, Martyn P.; Pupulin, Franco; Warner, Jorge; Hawkins, Julie A.; Salamin, Nicolas; Chittka, Lars; Williams, Norris H.; Whitten, W. Mark; Loader, Deniz; Valente, Luis M.; Chase, Mark W.; Savolainen, Vincent

    2013-01-01

    The great majority of plant species in the tropics require animals to achieve pollination, but the exact role of floral signals in attraction of animal pollinators is often debated. Many plants provide a floral reward to attract a guild of pollinators, and it has been proposed that floral signals of non-rewarding species may converge on those of rewarding species to exploit the relationship of the latter with their pollinators. In the orchid family (Orchidaceae), pollination is almost universally animal-mediated, but a third of species provide no floral reward, which suggests that deceptive pollination mechanisms are prevalent. Here, we examine floral colour and shape convergence in Neotropical plant communities, focusing on certain food-deceptive Oncidiinae orchids (e.g. Trichocentrum ascendens and Oncidium nebulosum) and rewarding species of Malpighiaceae. We show that the species from these two distantly related families are often more similar in floral colour and shape than expected by chance and propose that a system of multifarious floral mimicry—a form of Batesian mimicry that involves multiple models and is more complex than a simple one model–one mimic system—operates in these orchids. The same mimetic pollination system has evolved at least 14 times within the species-rich Oncidiinae throughout the Neotropics. These results help explain the extraordinary diversification of Neotropical orchids and highlight the complexity of plant–animal interactions. PMID:23804617

  18. Convergent evolution of floral signals underlies the success of Neotropical orchids.

    PubMed

    Papadopulos, Alexander S T; Powell, Martyn P; Pupulin, Franco; Warner, Jorge; Hawkins, Julie A; Salamin, Nicolas; Chittka, Lars; Williams, Norris H; Whitten, W Mark; Loader, Deniz; Valente, Luis M; Chase, Mark W; Savolainen, Vincent

    2013-08-22

    The great majority of plant species in the tropics require animals to achieve pollination, but the exact role of floral signals in attraction of animal pollinators is often debated. Many plants provide a floral reward to attract a guild of pollinators, and it has been proposed that floral signals of non-rewarding species may converge on those of rewarding species to exploit the relationship of the latter with their pollinators. In the orchid family (Orchidaceae), pollination is almost universally animal-mediated, but a third of species provide no floral reward, which suggests that deceptive pollination mechanisms are prevalent. Here, we examine floral colour and shape convergence in Neotropical plant communities, focusing on certain food-deceptive Oncidiinae orchids (e.g. Trichocentrum ascendens and Oncidium nebulosum) and rewarding species of Malpighiaceae. We show that the species from these two distantly related families are often more similar in floral colour and shape than expected by chance and propose that a system of multifarious floral mimicry--a form of Batesian mimicry that involves multiple models and is more complex than a simple one model-one mimic system--operates in these orchids. The same mimetic pollination system has evolved at least 14 times within the species-rich Oncidiinae throughout the Neotropics. These results help explain the extraordinary diversification of Neotropical orchids and highlight the complexity of plant-animal interactions. PMID:23804617

  19. First record of the orchid bee genus Eufriesea Cockerell (Hymenoptera: Apidae: Euglossini) in the United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A new species of orchid bee, Eufriesea aenigma Griswold and Herndon, is described from the Guadalupe Mountains of western Texas and southeastern New Mexico, USA. This is the first record for Eufriesea from the USA and extends its apparent range well beyond its previous, entirely tropical boundaries...

  20. The Doctrine of Signatures, Materia Medica of Orchids, and the Contributions of Doctor - Orchidologists.

    PubMed

    Pearn, John

    2012-12-01

    The heritage of medicine is written in many forms. One repository is to be found in the history of orchids, the world's largest family of flowering plants. Orchids were so named by Theophrastus (c.372-288 BC) who recorded their medicinal use as an aphrodisiac and the promoter of virility, in the context of the Doctrine of Signatures. Such use endured for millennia, and was recorded both by Paracelsus (1493-1551) and Linnaeus (1707-1778). The history of orchidology and medicine are entwined in four domains: (a) orchids and their historical materia medica, within the paradigm of the Doctrine of Signatures; (b) the enduring and extensive contemporary medicinal and culinary use of orchids such as Vanilla and salep extracts of Orchis; (c) the scientific contributions of doctors as orchidologists; and (d) the heritage of more than a hundred doctors' names in the scientific etymology of the Orchidaceae family. Prominent orchidologists have included the Scottish doctor-soldier and botanist, Robert Brown (1773-1858); the Director of the State Herbarium at Leyden and the Rijks Museum, Carl Ludwig Blume (1796-1862); and Dr William Sterling MD (1888-1967). Among the more than 1250 genus names (and 33,000 species) of orchids are the names of more than a hundred doctors, their lives and works perpetuated in the scientific etymology of this family of exotic, beautiful, flamboyant, intriguing and often expensive flowers. Generic names record the lives and works of such as Aristotle (384-322BC) in Aristotelia Loureiro 1790; Cadet de Gassicourt (1769-1821) in Cadetia Gaudichaud 1826; Sir Joseph Dalton Hooker (1817-1911) in Sirhookera O. Kuntze 1891; and Dr Theodore Daniel Vrydag Zynen (fl. 1820-1850) in Vrydagzynea Blume 1858. One of the principal horticultural genera of orchids, Brassavola, records the life and work of the Ferrara and Padua physician and botanist, Antonio Musa Brassavola (1500-1555). The first Slipper Orchid bred as a hybrid, Paphiopedilum harrisianum (by John

  1. Niche analysis and conservation of the orchids of east Macedonia (NE Greece)

    NASA Astrophysics Data System (ADS)

    Tsiftsis, Spyros; Tsiripidis, Ioannis; Karagiannakidou, Vassiliki; Alifragis, Dimitrios

    2008-01-01

    The orchid family is one of the largest in the flowering plant kingdom and includes a lot of rare, threatened or endangered species. The determination of plant species niche is considered fundamental for their conservation. Two parameters closely related with species niche are niche marginality and breadth. The first parameter is a measure of how typical or atypical a species niche is within an area, while the second is a measure of species tolerance. This study deals with niche analysis of the orchids of east Macedonia (NE Greece). Factors that are known to determine species distribution on a regional scale, such as altitude, aspect, habitat type, bedrock type and soil properties (acidity, organic matter, and phosphorus content) were used as explanatory variables. Geographical coordinates were also employed in order to explore spatial patterns in orchid distribution. Niche analysis was carried out using the Outlying Mean Index (OMI) analysis. Out of the total data of 55 taxa that were analyzed, 41 had a significant marginal niche compared with the average niche of the study area. Altitude, soil acidity and certain habitat types were found to be the most important factors in determining orchid distribution. Five different species groups were distinguished on the basis of their ecological preferences and niche breadth. Species niche marginality and breadth, the amplitude of their geographical distribution, the size of their populations and the rareness and conservation status of their habitats were taken into account in order to set conservation priorities for the orchids in the study area. The above characteristics combined with intuitive criteria (e.g. geographical distribution, endemicity) for the species with a small number of occurrences could form a sound basis for setting conservation priorities.

  2. Transcriptome-wide analysis of the MADS-box gene family in the orchid Erycina pusilla.

    PubMed

    Lin, Choun-Sea; Hsu, Chen-Tran; Liao, De-Chih; Chang, Wan-Jung; Chou, Ming-Lun; Huang, Yao-Ting; Chen, Jeremy J W; Ko, Swee-Suak; Chan, Ming-Tsair; Shih, Ming-Che

    2016-01-01

    Orchids exhibit a range of unique flower shapes and are a valuable ornamental crop. MADS-box transcription factors are key regulatory components in flower initiation and development. Changing the flower shape and flowering time can increase the value of the orchid in the ornamental horticulture industry. In this study, 28 MADS-box genes were identified from the transcriptome database of the model orchid Erycina pusilla. The full-length genomic sequences of these MADS-box genes were obtained from BAC clones. Of these, 27 were MIKC-type EpMADS (two truncated forms) and one was a type I EpMADS. Eleven EpMADS genes contained introns longer than 10 kb. Phylogenetic analysis classified the 24 MIKC(c) genes into nine subfamilies. Three specific protein motifs, AG, FUL and SVP, were identified and used to classify three subfamilies. The expression profile of each EpMADS gene correlated with its putative function. The phylogenetic analysis was highly correlated with the protein domain identification and gene expression results. Spatial expression of EpMADS6, EpMADS12 and EpMADS15 was strongly detected in the inflorescence meristem, floral bud and seed via in situ hybridization. The subcellular localization of the 28 EpMADS proteins was also investigated. Although EpMADS27 lacks a complete MADS-box domain, EpMADS27-YFP was localized in the nucleus. This characterization of the orchid MADS-box family genes provides useful information for both orchid breeding and studies of flowering and evolution. PMID:25917508

  3. Terrestrial orchids in a tropical forest: best sites for abundance differ from those for reproduction.

    PubMed

    Whitman, Melissa; Ackerman, James D

    2015-03-01

    Suitable habitat for a species is often modeled by linking its distribution patterns with landscape characteristics. However, modeling the relationship between fitness and landscape characteristics is less common. In this study we take a novel approach towards species distribution modeling (SDM) by investigating factors important not only for species occurrence, but also abundance and physical size, as well as fitness measures. We used the Neotropical terrestrial orchid Prescottia stachyodes as our focal species, and compiled geospatial information on habitat and neighboring plants for use in a two-part conditional SDM that accounted for zero inflation and reduced spatial autocorrelation bias. First, we modeled orchid occurrence, and then within suitable sites we contrasted habitat characteristics important for orchid abundance as compared to plant size. We then tested possible fitness implications, informed by analyses of allometric scaling of reproductive effort and lamina area, as well as size-density relationships in areas of P. stachyodes co-occurrence. We determined that orchid presence was based on a combination of biotic and abiotic factors (indicator species, diffuse solar radiation). Within these sites, P. stachyodes abundance was higher on flat terrain, with fine, moderately well-drained soil, and areas without other native orchids, whereas plant size was greater in less rocky areas. In turn, plant size determined reproductive effort, with floral display height proportionate to lamina area (more photosynthates); however, allometric scaling of flower quantity suggests a higher energy cost for production, or maintenance, of flowers. Overall, habitat factors most important for abundance differed from those for size (and thus reproductive effort), suggesting that sites optimal for either recruitment or survival may not be the primary source of seeds. For plots with multiple P. stachyodes plants, size-density relationships differed depending on the size class

  4. Orchids and Bee's Knees: Investigating the Euglossine Syndrome with Gas Chromatography/Fourier Transform Infrared GC/FT-IR

    NASA Astrophysics Data System (ADS)

    McClure, Gregory L.; Williams, N. H...; Whitten, W. M.

    1985-12-01

    The GC/FT-IR analysis of a fragrance obtained from a Gongora tricolor orchid is described. The significance of this type of analysis is explained in terms of the elucidation of the complex relationship between orchids and bees known as "The Euglossine Syndrome". The fragrance sample was found to contain p-cresol, p-methylanisole and a variety of terpenoids, including myrcene, cineole, limonene, cymene, ipsdienol, and an olefinic product which appears to be the dehydration product of ipsdienol.

  5. ESTs Analysis Reveals Putative Genes Involved in Symbiotic Seed Germination in Dendrobium officinale

    PubMed Central

    Zhao, Ming-Ming; Zhang, Gang; Zhang, Da-Wei; Hsiao, Yu-Yun; Guo, Shun-Xing

    2013-01-01

    Dendrobiumofficinale (Orchidaceae) is one of the world’s most endangered plants with great medicinal value. In nature, D. officinale seeds must establish symbiotic relationships with fungi to germinate. However, the molecular events involved in the interaction between fungus and plant during this process are poorly understood. To isolate the genes involved in symbiotic germination, a suppression subtractive hybridization (SSH) cDNA library of symbiotically germinated D. officinale seeds was constructed. From this library, 1437 expressed sequence tags (ESTs) were clustered to 1074 Unigenes (including 902 singletons and 172 contigs), which were searched against the NCBI non-redundant (NR) protein database (E-value cutoff, e-5). Based on sequence similarity with known proteins, 579 differentially expressed genes in D. officinale were identified and classified into different functional categories by Gene Ontology (GO), Clusters of orthologous Groups of proteins (COGs) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. The expression levels of 15 selected genes emblematic of symbiotic germination were confirmed via real-time quantitative PCR. These genes were classified into various categories, including defense and stress response, metabolism, transcriptional regulation, transport process and signal transduction pathways. All transcripts were upregulated in the symbiotically germinated seeds (SGS). The functions of these genes in symbiotic germination were predicted. Furthermore, two fungus-induced calcium-dependent protein kinases (CDPKs), which were upregulated 6.76- and 26.69-fold in SGS compared with un-germinated seeds (UGS), were cloned from D. officinale and characterized for the first time. This study provides the first global overview of genes putatively involved in D. officinale symbiotic seed germination and provides a foundation for further functional research regarding symbiotic relationships in orchids. PMID:23967335

  6. Growth Promotion-Related miRNAs in Oncidium Orchid Roots Colonized by the Endophytic Fungus Piriformospora indica

    PubMed Central

    Lin, Yuling; Chen, Peng-Jen; Xu, Xuming; Oelmüller, Ralf; Yeh, Kai-Wun; Lai, Zhongxiong

    2014-01-01

    Piriformospora indica, an endophytic fungus of Sebacinales, colonizes the roots of a wide range of host plants and establishes various benefits for the plants. In this work, we describe miRNAs which are upregulated in Oncidium orchid roots after colonization by the fungus. Growth promotion and vigorous root development were observed in Oncidium hybrid orchid, while seedlings were colonized by P. indica. We performed a genome-wide expression profiling of small RNAs in Oncidium orchid roots either colonized or not-colonized by P. indica. After sequencing, 24,570,250 and 24744,141 clean reads were obtained from two libraries. 13,736 from 17,036,953 unique sequences showed homology to either 86 miRNA families described in 41 plant species, or to 46 potential novel miRNAs, or to 51 corresponding miRNA precursors. The predicted target genes of these miRNAs are mainly involved in auxin signal perception and transduction, transcription, development and plant defense. The expression analysis of miRNAs and target genes demonstrated the regulatory functions they may participate in. This study revealed that growth stimulation of the Oncidium orchid after colonization by P. indica includes an intricate network of miRNAs and their targets. The symbiotic function of P. indica on Oncidium orchid resembles previous findings on Chinese cabbage. This is the first study on growth regulation and development of Oncidium orchid by miRNAs induced by the symbiotic fungus P. indica. PMID:24409313

  7. Tropical Epiphytic Orchids as an Object of Space Botany Investigations and a Design Element for Spacecraft Flight Decks and Orbital Stations

    NASA Astrophysics Data System (ADS)

    Cherevchenko, T. M.; Zaimenko, N. V.

    Epiphytic orchids are shown to be more stable in a long stay on board an orbital station than terrestrial species. Simulations revealed that the activity of native growth stimulators (free auxins and gibberellines) under the prolonged clinostating conditions varied in epiphytic orchids to a lesser extent than in terrestrial orchids. This factor, together with a weaker geotropic reaction, seems to be a cause of their stability in microgravitation conditions. The authors found also that orchids with the monopodial type of shoot system branching are less stable at microgravity than the sympodial species.

  8. Evolution and diversity of floral scent chemistry in the euglossine bee-pollinated orchid genus Gongora

    PubMed Central

    Hetherington-Rauth, Molly C.; Ramírez, Santiago R.

    2016-01-01

    •Background and Aims Animal-pollinated angiosperms have evolved a variety of signalling mechanisms to attract pollinators. Floral scent is a key component of pollinator attraction, and its chemistry modulates both pollinator behaviour and the formation of plant–pollinator networks. The neotropical orchid genus Gongora exhibits specialized pollinator associations with male orchid bees (Euglossini). Male bees visit orchid flowers to collect volatile chemical compounds that they store in hind-leg pouches to use subsequently during courtship display. Hence, Gongora floral scent compounds simultaneously serve as signalling molecules and pollinator rewards. Furthermore, because floral scent acts as the predominant reproductive isolating barrier among lineages, it has been hypothesized that chemical traits are highly species specific. A comparative analysis of intra- and inter-specific variation of floral scent chemistry was conducted to investigate the evolutionary patterns across the genus. •Methods Gas chromatography–mass spectrometry (GC-MS) was used to analyse the floral scent of 78 individuals belonging to 28 different species of Gongora from two of the three major lineages sampled across the neotropical region. Multidimensional scaling and indicator value analyses were implemented to investigate the patterns of chemical diversity within and among taxonomic groups at various geographic scales. Additionally, pollinator observations were conducted on a sympatric community of Gongora orchids exhibiting distinct floral scent phenotypes. •Key Results A total of 83 floral volatiles, mainly terpenes and aromatic compounds, were detected. Many of the identified compounds are common across diverse angiosperm families (e.g. cineole, eugenol, β-ocimene, β-pinene and terpinen-4-ol), while others are relatively rare outside euglossine bee-pollinated orchid lineages. Additionally, 29 volatiles were identified that are known to attract and elicit collection behaviour

  9. Large-Range Movements of Neotropical Orchid Bees Observed via Radio Telemetry

    PubMed Central

    Wikelski, Martin; Moxley, Jerry; Eaton-Mordas, Alexander; López-Uribe, Margarita M.; Holland, Richard; Moskowitz, David; Roubik, David W.; Kays, Roland

    2010-01-01

    Neotropical orchid bees (Euglossini) are often cited as classic examples of trapline-foragers with potentially extensive foraging ranges. If long-distance movements are habitual, rare plants in widely scattered locations may benefit from euglossine pollination services. Here we report the first successful use of micro radio telemetry to track the movement of an insect pollinator in a complex and forested environment. Our results indicate that individual male orchid bees (Exaerete frontalis) habitually use large rainforest areas (at least 42–115 ha) on a daily basis. Aerial telemetry located individuals up to 5 km away from their core areas, and bees were often stationary, for variable periods, between flights to successive localities. These data suggest a higher degree of site fidelity than what may be expected in a free living male bee, and has implications for our understanding of biological activity patterns and the evolution of forest pollinators. PMID:20520813

  10. Cross-amplification and characterization of microsatellite loci for the Neotropical orchid genus Epidendrum

    PubMed Central

    2009-01-01

    In this study we tested the cross-amplification of 33 microsatellite loci previously developed for two closely related Neotropical orchid genera (Epidendrum and Laelia). A set of ten loci were polymorphic across five examined species (20 individuals each) with 2 to 15 alleles per locus. The mean expected and observed heterozygosity (average across species) ranged from 0.34 to 0.82 and from 0.27 to 0.85, respectively. In addition we tested all loci in 35 species representative of the genus Epidendrum. Of these, 26 loci showed successful amplification. Cross-application of these loci represent a potential source of co-dominant markers for evolutionary, ecological and conservation studies in this important orchid genus. PMID:21637689

  11. Comparison of orchid and OCD modeling SO{sub x} release in the Gulf of Mexico

    SciTech Connect

    Ferris, D.C.; Burns, D.S.; Steorts, W.L.

    1996-10-01

    Two atmospheric chemistry and transport models are used to investigate the atmospheric behavior of SO{sub x} in the Gulf of Mexico. SO{sub x} emissions from a location about 30 miles offshore in the Gulf of Mexico will be modeled with ENSCO`s Short-range Layered Atmospheric Model (SLAM) and the EPA and Material Management Service (MMS) sanctioned Offshore and Coastal Dispersion Model (OCD). The atmospheric chemistry associated with SLAM is modeled using ENSCO`s ORganic CHemistry Integrated Dispersion Model (ORCHID) and has been developed from the Carbon Bond Mechanism (CBM-IV) to characterize the behavior of SO{sub x} compounds in the environment. Model runs from both ORCHID and OCD will be presented and compared. Predicted SO{sub x} concentrations will be compared with actual data gathered from the MMS`s SO{sub x} air quality study in 1993.

  12. Some results from studies on the effects of weightlessness on the growth of epiphytic orchids

    NASA Technical Reports Server (NTRS)

    Cherevchenko, T. M.; Mayko, T. K.

    1983-01-01

    Epidendrum orchids were placed in a Malakhit-2 micro-greenhouse aboard the Soyuz-36-Salyut-6 space station to test their growth under weightless conditions. Growth occurred but was less than in control plants left on Earth; cells were smaller and parenchymal development slowed in all tissues. Stems, roots, and leaves were smaller. The number of stomas on the leaves was about the same as in the controls, but, because of the smaller leaf size, there were more per unit area. A modeling experiment using a clinostat revealed a large decrease in gibberellin activity and auxin activity. It was assumed that weightlessness primarily affects gibberellin biosynthesis, inhibiting cell growth. Reestablishment of growth compound activity upon return of the plants to Earth was indicated by the fact that the orchids resumed growth thereafter.

  13. Effect of simulated microgravitation on phytohormones and cell structure of tropical orchids

    NASA Astrophysics Data System (ADS)

    Cherevchenko, T.; Zaimenko, N.; Majko, T.; Sytnjanskaja, N.

    When studing the effect of two month clinostating on the phytohormonal system of orchids with different types of shoot system branching and different shoot morphology, it was determined that, as a result of simulated microgravitation, endogenous growth regulators changed less in the species with sympodial branching than in species with monopodial branching and without pseudobulbs. Stimulators prevail in the balance of growth regulators in species of the first type and inhibitors in species of the second type. Besides this, comparative analysis of structural organization of juvenile leaf surface tissue of tested orchids was carried out. Variability of size, number and structure of stomatal organization were found according to species belonging to each branching type after clinostating. Electronic microscope studies show some structural peculiarities of epidermal and mesophilous cells.

  14. Bioguided identification of antifungal and antiproliferative compounds from the Brazilian orchid Miltonia flavescens Lindl.

    PubMed

    Porte, Leticia F; Santin, Silvana M O; Chiavelli, Lucas U R; Silva, Cleuza C; Faria, Terezinha J; Faria, Ricardo T; Ruiz, Ana L T G; Carvalho, João E; Pomini, Armando M

    2014-01-01

    The Orchidaceae family is appreciated worldwide for the beauty of its flowers, and hundreds of species of this family occur in Brazil. Yet little is known about the potential of orchids for therapeutic application. We have investigated bioactive compounds produced by the South Brazilian orchid Miltonia flavescens Lindl. Bioguided studies with the fungus Cladosporium herbarum allowed the identification of hydrocinnamic acid as the active antifungal compound. In addition, the chloroform fraction exhibited an interesting activity against human cancer cells, and 5,7-dihydroxy-6,4'-dimethoxyflavone isolated from this fraction was found to be active against seven human cancer cell lines, including NCI/ADR-RES ovary sarcoma, with an IC50 value of 2.6 microg/mL. This is the first report on the cytostatic activity of this flavone against human ovary sarcoma. PMID:24772822

  15. A garden of orchids: a generalized Harper equation at quadratic irrational frequencies

    NASA Astrophysics Data System (ADS)

    Mestel, B. D.; Osbaldestin, A. H.

    2004-10-01

    We consider a generalized Harper equation at quadratic irrational flux, showing, in the strong coupling limit, the fluctuations of the exponentially decaying eigenfunctions are governed by the dynamics of a renormalization operator on a renormalization strange set. This work generalizes previous analyses which have considered only the golden mean case. Projections of the renormalization strange sets are illustrated analogous to the 'orchid' present in the golden mean case.

  16. In planta transformation method for T-DNA transfer in orchids

    NASA Astrophysics Data System (ADS)

    Semiarti, Endang; Purwantoro, Aziz; Mercuriani, Ixora S.; Anggriasari, Anida M.; Jang, Seonghoe; Suhandono, Sony; Machida, Yasunori; Machida, Chiyoko

    2014-03-01

    Transgenic plant technology is an efficient tool to study the function of gene(s) in plant. The most popular and widely used technique is Agrobacterium-mediated transformation in which cocultivation was done by immersing the plant tissues/organ in overnight bacterial cultured for about 30 minutes to one hour under in vitro condition. In this experiment, we developed more easier technique that omitted the in vitro step during cocultivation with Agrobacterium, namely in planta transformation method. Pollinaria (compact pollen mass of orchid) of Phalaenopsis amabilis and Spathoglottis plicata orchids were used as target explants that were immersed into bacterial culture for 30 minutes, then dried up the pollinaria, the transformed pollinaria was used to pollinate orchid flowers. The T-DNA used for this experiments were Ubipro∷PaFT/A. tumefaciens GV3101 for P. amabilis and MeEF1α2 pro∷GUS/ A. tumefaciens LBA 4404 for S.plicata. Seeds that were produced from pollinated flowers were grown onto 10 mg/l hygromicin containing NP (New Phalaenopsis) medium. The existance of transgene in putative transformant protocorm (developing orchid embryo) genome was confirmed using PCR with specific primers of either PaFT or GUS genes. Histochemical GUS assay was also performed to the putative transformants. The result showed that transformation frequencies were 2.1 % in P. amabilis, and 0,53% in S. plicata. These results indicates that in planta transformation method could be used for Agrobacterium-mediated genetic transformation, with advantage easier and more secure work from contaminants than that of the in vitro method.

  17. Intraspecific Geographic Variation of Fragrances Acquired by Orchid Bees in Native and Introduced Populations

    PubMed Central

    Eltz, Thomas; Fritzsch, Falko; Pemberton, Robert; Pringle, Elizabeth G.; Tsutsui, Neil D.

    2010-01-01

    Male orchid bees collect volatiles, from both floral and non-floral sources, that they expose as pheromone analogues (perfumes) during courtship display. The chemical profile of these perfumes, which includes terpenes and aromatic compounds, is both species-specific and divergent among closely related lineages. Thus, fragrance composition is thought to play an important role in prezygotic reproductive isolation in euglossine bees. However, because orchid bees acquire fragrances entirely from exogenous sources, the chemical composition of male perfumes is prone to variation due to environmental heterogeneity across habitats. We used Gas Chromatography/Mass Spectrometry (GC/MS) to characterize the perfumes of 114 individuals of the green orchid bee (Euglossa aff. viridissima) sampled from five native populations in Mesoamerica and two naturalized populations in the southeastern United States. We recorded a total of 292 fragrance compounds from hind-leg extracts, and found that overall perfume composition was different for each population. We detected a pronounced chemical dissimilarity between native (Mesoamerica) and naturalized (U.S.) populations that was driven both by proportional differences of common compounds as well as the presence of a few chemicals unique to each population group. Despite these differences, our data also revealed remarkable qualitative consistency in the presence of several major fragrance compounds across distant populations from dissimilar habitats. In addition, we demonstrate that naturalized bees are attracted to and collect large quantities of triclopyr 2-butoxyethyl ester, the active ingredient of several commercially available herbicides. By comparing incidence values and consistency indices across populations, we identify putative functional compounds that may play an important role in courtship signaling in this species of orchid bee. Electronic supplementary material The online version of this article (doi:10.1007/s10886

  18. Intraspecific geographic variation of fragrances acquired by orchid bees in native and introduced populations.

    PubMed

    Ramírez, Santiago R; Eltz, Thomas; Fritzsch, Falko; Pemberton, Robert; Pringle, Elizabeth G; Tsutsui, Neil D

    2010-08-01

    Male orchid bees collect volatiles, from both floral and non-floral sources, that they expose as pheromone analogues (perfumes) during courtship display. The chemical profile of these perfumes, which includes terpenes and aromatic compounds, is both species-specific and divergent among closely related lineages. Thus, fragrance composition is thought to play an important role in prezygotic reproductive isolation in euglossine bees. However, because orchid bees acquire fragrances entirely from exogenous sources, the chemical composition of male perfumes is prone to variation due to environmental heterogeneity across habitats. We used Gas Chromatography/Mass Spectrometry (GC/MS) to characterize the perfumes of 114 individuals of the green orchid bee (Euglossa aff. viridissima) sampled from five native populations in Mesoamerica and two naturalized populations in the southeastern United States. We recorded a total of 292 fragrance compounds from hind-leg extracts, and found that overall perfume composition was different for each population. We detected a pronounced chemical dissimilarity between native (Mesoamerica) and naturalized (U.S.) populations that was driven both by proportional differences of common compounds as well as the presence of a few chemicals unique to each population group. Despite these differences, our data also revealed remarkable qualitative consistency in the presence of several major fragrance compounds across distant populations from dissimilar habitats. In addition, we demonstrate that naturalized bees are attracted to and collect large quantities of triclopyr 2-butoxyethyl ester, the active ingredient of several commercially available herbicides. By comparing incidence values and consistency indices across populations, we identify putative functional compounds that may play an important role in courtship signaling in this species of orchid bee. PMID:20623328

  19. Why are orchid flowers so diverse? Reduction of evolutionary constraints by paralogues of class B floral homeotic genes

    PubMed Central

    Mondragón-Palomino, Mariana; Theißen, Günter

    2009-01-01

    Background The nearly 30 000 species of orchids produce flowers of unprecedented diversity. However, whether specific genetic mechanisms contributed to this diversity is a neglected topic and remains speculative. We recently published a theory, the ‘orchid code’, maintaining that the identity of the different perianth organs is specified by the combinatorial interaction of four DEF-like MADS-box genes with other floral homeotic genes. Scope Here the developmental and evolutionary implications of our theory are explored. Specifically, it is shown that all frequent floral terata, including all peloric types, can be explained by monogenic gain- or-loss-of-function mutants, changing either expression of a DEF-like or CYC-like gene. Supposed dominance or recessiveness of mutant alleles is correlated with the frequency of terata in both cultivation and nature. Our findings suggest that changes in DEF- and CYC-like genes not only underlie terata but also the natural diversity of orchid species. We argue, however, that true changes in organ identity are rare events in the evolution of orchid flowers, even though we review some likely cases. Conclusions The four DEF paralogues shaped floral diversity in orchids in a dramatic way by modularizing the floral perianth based on a complex series of sub- and neo-functionalization events. These genes may have eliminated constraints, so that different kinds of perianth organs could then evolve individually and thus often in dramatically different ways in response to selection by pollinators or by genetic drift. We therefore argue that floral diversity in orchids may be the result of an unprecedented developmental genetic predisposition that originated early in orchid evolution. PMID:19141602

  20. NIR-assisted orchid virus therapy using urchin bimetallic nanomaterials in phalaenopsis

    NASA Astrophysics Data System (ADS)

    Chen, Shin-Yu; Cheng, Liang-Chien; Chen, Chieh-Wei; Lee, Po-Han; Yu, Fengjiao; Zhou, Wuzong; Liu, Ru-Shi; Do, Yi-Yin; Huang, Pung-Ling

    2013-12-01

    The use of nanoparticles has drawn special attention, particularly in the treatment of plant diseases. Cymbidium mosaic virus (CymMV) and Odontoglossum ring spot virus (ORSV) are the most prevalent and serious diseases that affect the development of the orchid industry. In this study we treated nanoparticles as a strategy for enhancing the resistance of orchids against CymMV and ORSV. After chitosan-modified gold nanoparticles (Au NPs) were injected into Phalaenopsis leaves, the injected leaves were exposed to 980 nm laser for light-heat conversion. To evaluate virus elimination in the treated Phalaenopsis leaves, the transcripts of coat protein genes and the production of viral proteins were assessed by reverse transcription-Polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. The expression of coat protein genes for both CymMV and ORSV was significantly lower in the chitosan-modified Au NP-treated Phalaenopsis leaves than in the control. Similarly, the amount of coat proteins for both viruses in the Phalaenopsis leaves was lower than that in the control (without nanoparticle injection). We propose that the temperature increase in the chitosan-modified Au NP-treated Phalaenopsis tissues after laser exposure reduces the viral population, consequently conferring resistance against CymMV and ORSV. Our findings suggest that the application of chitosan-modified Au NPs is a promising new strategy for orchid virus therapy.

  1. Evolutionary history of PEPC genes in green plants: Implications for the evolution of CAM in orchids.

    PubMed

    Deng, Hua; Zhang, Liang-Sheng; Zhang, Guo-Qiang; Zheng, Bao-Qiang; Liu, Zhong-Jian; Wang, Yan

    2016-01-01

    The phosphoenolpyruvate carboxylase (PEPC) gene is the key enzyme in CAM and C4 photosynthesis. A detailed phylogenetic analysis of the PEPC family was performed using sequences from 60 available published plant genomes, the Phalaenopsis equestris genome and RNA-Seq of 15 additional orchid species. The PEPC family consists of three distinct subfamilies, PPC-1, PPC-2, and PPC-3, all of which share a recent common ancestor in chlorophyte algae. The eudicot PPC-1 lineage separated into two clades due to whole genome duplication (WGD). Similarly, the monocot PPC-1 lineage also divided into PPC-1M1 and PPC-1M2 through an ancient duplication event. The monocot CAM- or C4-related PEPC originated from the clade PPC-1M1. WGD may not be the major driver for the performance of CAM function by PEPC, although it increased the number of copies of the PEPC gene. CAM may have evolved early in monocots, as the CAM-related PEPC of orchids originated from the monocot ancient duplication, and the earliest CAM-related PEPC may have evolved immediately after the diversification of monocots, with CAM developing prior to C4. Our results represent the most complete evolutionary history of PEPC genes in green plants to date and particularly elucidate the origin of PEPC in orchids. PMID:26493226

  2. Microsatellite primers for two threatened orchids in Florida: Encyclia tampensis and Cyrtopodium punctatum (Orchidaceae)1

    PubMed Central

    Weremijewicz, Joanna; Almonte, Jasmin I.; Hilaire, Vanessa S.; Lopez, Frank D.; Lu, Stephen H.; Marrero, Sarah M.; Martinez, Catherine M.; Zarate, Edson A.; Lam, Ana K.; Ferguson, Samantha A. N.; Petrakis, Nicolas Z.; Peeples, Kelsey A.; Taylor, Ebony D.; Leon, Natalie M.; Valdes, Carolina; Hass, Michael; Reeve, Andrew B.; Palow, Danielle T.; Downing, Jason L.

    2016-01-01

    Premise of the study: The Million Orchid Project at Fairchild Tropical Botanic Garden is an initiative to propagate native orchids for reintroduction into Miami’s urban landscapes. The aim of this study was to develop microsatellites for Encyclia tampensis and Cyrtopodium punctatum (Orchidaceae). Methods and Results: Ten microsatellites were developed for each species. For E. tampensis sampled from the natural population, allele numbers ranged from one to four, with an average observed heterozygosity (Ho) of 0.314 and average expected heterozygosity (He) of 0.281. For the individuals from cultivation, allele numbers ranged from one to six, with an average Ho of 0.35 and an average He of 0.224. For C. punctatum, allele numbers ranged from one to three, with an average Ho of 0.257 and an average He of 0.272. Conclusions: These microsatellites will be used to assess the genetic diversity of natural and cultivated populations with the intention of guiding genetic breeding under the Million Orchid Project. PMID:27144103

  3. The Anther Steps onto the Stigma for Self-Fertilization in a Slipper Orchid

    PubMed Central

    Xiao, Xin-Ju; Tsai, Wen-Chieh; Hsiao, Yu-Yun; Huang, Jie; Liu, Zhong-Jian

    2012-01-01

    Background Due to the spatial separation between male and female pollen grains from the anther of most flowering plants, including orchids, pollens are transported by wind or animals and deposited onto the receptive surface of the stigma of a different plant. However, self-pollination is common in pollinating animal-scarce habitats. In such habitats, self-pollinations require the assistance of a pollinating agent (e.g., wind, gravity, or floral assembly) to transport the pollen grains from the anther onto its own stigma. Methodology/Principal Findings Based on observations on floral morphology and flowering phenology, tests of the breeding system, and a comparison of pollination mechanisms, a new self-pollination process was discovered in the hermaphroditic (i.e., possessing spatially separated male and female organs) flower of a slipper orchid, Paphiopedilum parishii. The anther changes from a solid to a liquid state and directly steps onto the stigma surface without the aid of any pollinating agent or floral assembly. Conclusions The mode of self-pollination discussed here is a new addition to the broad range of genetic and morphological mechanisms that have evolved in flowering plants to ensure their reproductive success. The present self-contained pollination mechanism is a possible adaptation to the insect-scarce habitat of the orchid. PMID:22649529

  4. Floral visual signal increases reproductive success in a sexually deceptive orchid

    PubMed Central

    Streinzer, Martin; Paulus, Hannes F.; Spaethe, Johannes

    2013-01-01

    Sexually deceptive orchids mimic signals emitted by female insects in order to attract mate-searching males. Specific attraction of the targeted pollinator is achieved by sex pheromone mimicry, which constitutes the major attraction channel. In close vicinity of the flower, visual signals may enhance attraction, as was shown recently in the sexually deceptive orchid Ophrys heldreichii. Here, we conducted an in situ manipulation experiment in two populations of O. heldreichii on Crete to investigate whether the presence/absence of the conspicuous pink perianth affects reproductive success in two natural orchid populations. We estimated reproductive success of three treatment groups (with intact, removed and artificial perianth) throughout the flowering period as pollinaria removal (male reproductive success) and massulae deposition (female reproductive success). Reproductive success was significantly increased by the presence of a strong visual signal—the conspicuous perianth—in one study population, however, not in the second, most likely due to the low pollinator abundance in the latter population. This study provides further evidence that the coloured perianth in O. heldreichii is adaptive and thus adds to the olfactory signal to maximise pollinator attraction and reproductive success. PMID:23750181

  5. The osmotic property and fluorescent tracer movement of developing orchid embryos of Phaius tankervilliae (Aiton) Bl.

    PubMed

    Lee, Yung-I; Yeung, Edward C

    2010-12-01

    The suspensor plays an active role during the early embryo development of flowering plants. In orchids, the suspensor cells are highly vacuolated without structural specializations, and the possible mechanism(s) that enable the suspensor to serve as the nutrient uptake site is virtually unknown. Here, we used the fluorescent tracer CFDA to characterize the pathway for symplastic transport in the suspensor cells of developing embryos and to provide direct visual evidence that the orchid suspensor has unique physiological properties. The embryo proper uptakes the fluorescent dye through the suspensor. CF could first be detected throughout the suspensor cell and then subsequently in the embryo proper. A plasmolysis experiment clearly indicates that suspensor cells have a more negative osmotic potential than the adjoining testa cells. It is proposed that the preferential entry of CFDA into the suspensor cell of the Nun orchid is aided by the more negative osmotic potential of the suspensor than neighboring cells, providing a driving force for the uptake of water from the apoplast into the symplast. PMID:20467876

  6. Cloning and characterization of a PI-like MADS-box gene in Phalaenopsis orchid.

    PubMed

    Guo, Bin; Hexige, Saiyin; Zhang, Tian; Pittman, Jon K; Chen, Donghong; Ming, Feng

    2007-11-30

    The highly evolved flowers of orchids have colorful sepals and fused columns that offer an opportunity to discover new genes involved in floral development in monocotyledon species. In this investigation, we cloned and characterized the homologous PISTALLATA-like (PI-like) gene PhPI15 (Phalaenopsis PI STILLATA # 15), from the Phalaenopsis hybrid cultivar. The protein sequence encoded by PhPI15 contains a typical PI-motif. Its sequence also formed a subclade with other monocot PI-type genes in phylogenetic analysis. Southern analysis showed that PhPI15 was present in the Phalaenopsis orchid genome as a single copy. Furthermore, it was expressed in all the whorls of the Phalaenopsis flower, while no expression was detected in vegetative organs. The flowers of transgenic tobacco plants ectopically expressing PhPI15 showed male-sterile phenotypes. Thus, as a Class-B MADS-box gene, PhPI15 specifies floral organ identity in orchids. PMID:18047777

  7. First description of necrosis in leaves and pseudo-bulbs of Oncidium orchids caused by Burkholderia gladioli in São Paulo State, Brazil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A necrosis of orchid leaves and pseudobulbs was observed in a commercial orchid nursery in Mogi das Cruzes, Sao Paulo, Brazil. The symptoms were water-soaked, brown lesions that can develop into large areas of necrosis that extend throughout the entire plant, ultimately causing death. Bacteria were...

  8. [Comparison on polysaccharide content and PMP-HPLC fingerprints of polysaccharide in stems and leaves of Dendrobium officinale].

    PubMed

    Zhou, Gui-Fen; Pang, Min-Xia; Chen, Su-Hong; Lv, Gui-Yuan; Yan, Mei-Qiu

    2014-03-01

    In order to provide scientific basics for exploitation and sufficient application of Dendrobium officinale leaves resources, the phenol-sulfuric acid method was applied to determine the polysaccharide content. The monosaccharides were derivated by PMP and the derivatives were identified by HPLC-DAD-ESI-MS(n) and the contents of mannose and glucose were determined simultaneously. Similarity evaluation system for chromatographic fingerprint of traditional Chinese medicine (2004A) was employed to generate the mean chromatogram and similarity analysis of the samples was carried out. The results demonstrated that polysaccharide content, monosaccharide compositions and composition ratio had an obvious difference between stems and leaves. The polysaccharide content of stems was higher than that of leaves. Monosaccharide composition in leaf was significantly different from that in stem. The polysaccharide from stems was composed of mannose and glucose, however the polysaccharide of leaves was acid heteropolysaccharide and was mainly composed of five monosaccharides, including mannose, galacturonic acid, glucose, galactose and arabinose. The similarity value of the 14 batches was above 0.9, indicating that similarity of fingerprints among different samples was high. The study can provide evidence for expanding the medicinal parts of D. officinale. PMID:25204167

  9. Qualitative and quantitative analysis of specific polysaccharides in Dendrobium huoshanense by using saccharide mapping and chromatographic methods.

    PubMed

    Deng, Yong; Chen, Ling-Xiao; Han, Bang-Xing; Wu, Ding-Tao; Cheong, Kit-Leong; Chen, Nai-Fu; Zhao, Jing; Li, Shao-Ping

    2016-09-10

    Qualitative and quantitative analysis of specific polysaccharides from ten batches of Dendrobium huoshanense were performed using high performance size exclusion chromatography coupled with multi-angle laser light scattering and refractive index detector (HPSEC-MALLS-RID), gas chromatography-mass spectrometry (GC-MS), nuclear magnetic resonance (NMR) and saccharide mapping based on polysaccharides analysis by using carbohydrate gel electrophoresis (PACE) and high performance thin layer chromatography (HPTLC). Results showed that molecular weights, the radius of gyrations, and contents of specific polysaccharides in D. huoshanense were ranging from 1.16×10(5) to 2.17×10(5)Da, 38.8 to 52.1nm, and 9.9% to 19.9%, respectively. Furthermore, the main monosaccharide compositions were Man and Glc. Indeed, the main glycosidic linkages were β-1,4-Manp and β-1,4-Glcp, and substituted with acetyl groups at O-2 and O-3 of 1,4-linked Manp. Moreover, results showed that PACE and HPTLC fingerprints of partial acidic and enzymatic hydrolysates of specific polysaccharides were similar, which are helpful to better understand the specific polysaccharides in D. huoshanense and beneficial to improve their quality control. These approaches could also be routinely used for quality control of polysaccharides in other medicinal plants. PMID:27424197

  10. Growth-promoting Sphingomonas paucimobilis ZJSH1 associated with Dendrobium officinale through phytohormone production and nitrogen fixation

    PubMed Central

    Yang, Suijuan; Zhang, Xinghai; Cao, Zhaoyun; Zhao, Kaipeng; Wang, Sai; Chen, Mingxue; Hu, Xiufang

    2014-01-01

    Growth-promoting Sphingomonas paucimobilis ZJSH1, associated with Dendrobium officinale, a traditional Chinese medicinal plant, was characterized. At 90 days post-inoculation, strain ZJSH1 significantly promoted the growth of D. officinale seedlings, with increases of stems by 8.6% and fresh weight by 7.5%. Interestingly, the polysaccharide content extracted from the inoculated seedlings was 0.6% higher than that of the control. Similar growth promotion was observed with the transplants inoculated with strain ZJSH1. The mechanism of growth promotion was attributed to a combination of phytohormones and nitrogen fixation. Strain ZJSH1 was found using the Kjeldahl method to have a nitrogen fixation activity of 1.15 mg l−1, which was confirmed by sequencing of the nifH gene. Using high-performance liquid chromatography-mass spectrometry, strain ZJSH1 was found to produce various phytohormones, including salicylic acid (SA), indole-3-acetic acid (IAA), Zeatin and abscisic acid (ABA). The growth curve showed that strain ZJSH1 grew well in the seedlings, especially in the roots. Accordingly, much higher contents of SA, ABA, IAA and c-ZR were detected in the inoculated seedlings, which may play roles as both phytohormones and ‘Systemic Acquired Resistance’ drivers. Nitrogen fixation and secretion of plant growth regulators (SA, IAA, Zeatin and ABA) endow S. paucimobilis ZJSH1 with growth-promoting properties, which provides a potential for application in the commercial growth of D. officinale. PMID:25142808

  11. (±)-Homocrepidine A, a Pair of Anti-inflammatory Enantiomeric Octahydroindolizine Alkaloid Dimers from Dendrobium crepidatum.

    PubMed

    Hu, Yang; Zhang, Chaofeng; Zhao, Xin; Wang, Yue; Feng, Deqiang; Zhang, Mian; Xie, Haifeng

    2016-01-22

    A pair of racemic indolizidine enantiomers, (±)-homocrepidine A (1), and a piperidine derivative, homocrepidine B (2), were isolated from Dendrobium crepidatum along with the known alkaloid crepidine (3). The racemic mixture of 1 was separated into a pair of enantiomers, (+)-1 and (-)-1, by HPLC using a chiral chromatographic substrate, which represents the first successful example of resolving indolizidine racemic mixtures. The absolute configurations of (+)-1 and (-)-1 were assigned from single-crystal X-ray diffraction data. The evaluation of anti-inflammatory activity with LPS-induced RAW 264.7 macrophages revealed that (+)-1 strongly inhibited the production of nitric oxide (IC50, 3.6 μM) and significantly decreased the expression of inducible nitric oxide synthase, while (-)-1 and (±)-1 only had moderate inhibitory effects (IC50, 22.8 and 14.7 μM). Compound 2 showed moderate anti-inflammatory activity (IC50, 27.6 μM). PMID:26710212

  12. Characterization of the alkaline/neutral invertase gene in Dendrobium officinale and its relationship with polysaccharide accumulation.

    PubMed

    Gao, F; Cao, X F; Si, J P; Chen, Z Y; Duan, C L

    2016-01-01

    Dendrobium officinale is one of the most well-known traditional Chinese medicines, and polysaccharide is its main active ingredient. Many studies have investigated the synthesis and accumulation mechanisms of polysaccharide, but until recently, little was known about the molecular mechanism of how polysaccharide is synthesized because no related genes have been cloned. In this study, we cloned an alkaline/neutral invertase gene from D. officinale (DoNI) by the rapid amplification of cDNA ends (RACE) method. DoNI was 2231 bp long and contained an open reading frame that predicted a 62.8-kDa polypeptide with 554-amino acid residues. An alkaline/neutral invertase conserved domain was predicted from this deduced amino acid sequence, and DoNI had a similar deduced amino acid sequence to Setaria italica and Oryza brachyantha. We also found that DoNI expression in different tissues was closely related to DoNI activity, and more importantly, polysaccharide level. Our results indicate that DoNI is associated with polysaccharide accumulation in D. officinale. PMID:27173310

  13. The loci recommended as universal barcodes for plants on the basis of floristic studies may not work with congeneric species as exemplified by DNA barcoding of Dendrobium species

    PubMed Central

    2012-01-01

    Background Based on the testing of several loci, predominantly against floristic backgrounds, individual or different combinations of loci have been suggested as possible universal DNA barcodes for plants. The present investigation was undertaken to check the applicability of the recommended locus/loci for congeneric species with Dendrobium species as an illustrative example. Results Six loci, matK, rbcL, rpoB, rpoC1, trnH-psbA spacer from the chloroplast genome and ITS, from the nuclear genome, were compared for their amplification, sequencing and species discrimination success rates among multiple accessions of 36 Dendrobium species. The trnH-psbA spacer could not be considered for analysis as good quality sequences were not obtained with its forward primer. Among the tested loci, ITS, recommended by some as a possible barcode for plants, provided 100% species identification. Another locus, matK, also recommended as a universal barcode for plants, resolved 80.56% species. ITS remained the best even when sequences of investigated loci of additional Dendrobium species available on the NCBI GenBank (93, 33, 20, 18 and 17 of ITS, matK, rbcL, rpoB and rpoC1, respectively) were also considered for calculating the percent species resolution capabilities. The species discrimination of various combinations of the loci was also compared based on the 36 investigated species and additional 16 for which sequences of all the five loci were available on GenBank. Two-locus combination of matK+rbcL recommended by the Plant Working Group of Consortium for Barcoding of Life (CBOL) could discriminate 86.11% of 36 species. The species discriminating ability of this barcode was reduced to 80.77% when additional sequences available on NCBI were included in the analysis. Among the recommended combinations, the barcode based on three loci - matK, rpoB and rpoC1- resolved maximum number of species. Conclusions Any recommended barcode based on the loci tested so far, is not likely to

  14. Exotic and indigenous viruses infect wild populations and captive collections of temperate terrestrial orchids (Diuris species) in Australia.

    PubMed

    Wylie, Stephen J; Li, Hua; Dixon, Kingsley W; Richards, Helen; Jones, Michael G K

    2013-01-01

    Four species of Diuris temperate terrestrial orchids from wild and captive populations were tested for the presence of polyadenylated RNA viruses. The genomes of three exotic viruses were determined: two potyviruses, Bean yellow mosaic virus and Ornithogalum mosaic virus, and the polerovirus Turnip yellows virus. The genomes of five indigenous viruses were detected, including four novel species. They were the potyvirus Blue squill virus A, another potyvirus, two proposed capilloviruses, and a partitivirus. Partitivirus infection is of interest as this group of viruses is also associated with endophytic fungi (mycorrhizae) that are necessary for the germination, growth, development of many terrestrial orchids. Sequence divergence data indicate post-European, pre-European, and endemic origins for these viruses via inoculum from introduced and native plants. The implications of the findings of this study for orchid conservation, and particularly reintroduction programs where viruses may be spread inadvertently to wild populations from infected propagation sources, are discussed. PMID:23089850

  15. Solitary invasive orchid bee outperforms co-occurring native bees to promote fruit set of an invasive Solanum.

    PubMed

    Liu, Hong; Pemberton, Robert W

    2009-03-01

    Our understanding of the effects of introduced invasive pollinators on plants has been exclusively drawn from studies on introduced social bees. One might expect, however, that the impacts of introduced solitary bees, with much lower population densities and fewer foragers, would be small. Yet little is known about the potential effects of naturalized solitary bees on the environment. We took advantage of the recent naturalization of an orchid bee, Euglossa viridissima, in southern Florida to study the effects of this solitary bee on reproduction of Solanum torvum, an invasive shrub. Flowers of S. torvum require specialized buzz pollination. Through timed floral visitor watches and two pollination treatments (control and pollen supplementation) at three forest edge and three open area sites, we found that the fruit set of S. torvum was pollen limited at the open sites where the native bees dominate, but was not pollen limited at the forest sites where the invasive orchid bees dominate. The orchid bee's pollination efficiency was nearly double that of the native halictid bees, and was also slightly higher than that of the native carpenter bee. Experiments using small and large mesh cages (to deny or allow E. viridissima access, respectively) at one forest site indicated that when the orchid bee was excluded, the flowers set one-quarter as many fruit as when the bee was allowed access. The orchid bee was the most important pollinator of the weed at the forest sites, which could pose additional challenges to the management of this weed in the fragmented, endangered tropical hardwood forests in the region. This specialized invasive mutualism may promote populations of both the orchid bee and this noxious weed. Invasive solitary bees, particularly species that are specialized pollinators, appear to have more importance than has previously been recognized. PMID:19066971

  16. Effects of pollination limitation and seed predation on female reproductive success of a deceptive orchid

    PubMed Central

    Walsh, Ryan P.; Arnold, Paige M.; Michaels, Helen J.

    2014-01-01

    For many species of conservation significance, multiple factors limit reproduction. This research examines the contributions of plant height, number of flowers, number of stems, pollen limitation and seed predation to female reproductive success in the deceit-pollinated orchid, Cypripedium candidum. The deceptive pollination strategy employed by many orchids often results in high levels of pollen limitation. While increased floral display size may attract pollinators, C. candidum's multiple, synchronously flowering stems could promote selfing and also increase attack by weevil seed predators. To understand the joint impacts of mutualists and antagonists, we examined pollen limitation, seed predation and the effects of pollen source over two flowering seasons (2009 and 2011) in Ohio. In 2009, 36 pairs of plants size-matched by flower number, receiving either supplemental hand or open pollination, were scored for fruit maturation, mass of seeds and seed predation. Pollen supplementation increased proportion of flowers maturing into fruit, with 87 % fruit set when hand pollinated compared with 46 % for naturally pollinated flowers. Inflorescence height had a strong effect, as taller inflorescences had higher initial fruit set, while shorter stems had higher predation. Seed predation was seen in 73 % of all fruits. A parallel 2011 experiment that included a self-pollination treatment and excluded seed predators found initial and final fruit set were higher in the self and outcross pollination treatments than in the open-pollinated treatment. However, seed mass was higher in both open pollinated and outcross pollination treatments compared with hand self-pollinated. We found greater female reproductive success for taller flowering stems that simultaneously benefited from increased pollination and reduced seed predation. These studies suggest that this species is under strong reinforcing selection to increase allocation to flowering stem height. Our results may help

  17. Effects of pollination limitation and seed predation on female reproductive success of a deceptive orchid.

    PubMed

    Walsh, Ryan P; Arnold, Paige M; Michaels, Helen J

    2014-01-01

    For many species of conservation significance, multiple factors limit reproduction. This research examines the contributions of plant height, number of flowers, number of stems, pollen limitation and seed predation to female reproductive success in the deceit-pollinated orchid, Cypripedium candidum. The deceptive pollination strategy employed by many orchids often results in high levels of pollen limitation. While increased floral display size may attract pollinators, C. candidum's multiple, synchronously flowering stems could promote selfing and also increase attack by weevil seed predators. To understand the joint impacts of mutualists and antagonists, we examined pollen limitation, seed predation and the effects of pollen source over two flowering seasons (2009 and 2011) in Ohio. In 2009, 36 pairs of plants size-matched by flower number, receiving either supplemental hand or open pollination, were scored for fruit maturation, mass of seeds and seed predation. Pollen supplementation increased proportion of flowers maturing into fruit, with 87 % fruit set when hand pollinated compared with 46 % for naturally pollinated flowers. Inflorescence height had a strong effect, as taller inflorescences had higher initial fruit set, while shorter stems had higher predation. Seed predation was seen in 73 % of all fruits. A parallel 2011 experiment that included a self-pollination treatment and excluded seed predators found initial and final fruit set were higher in the self and outcross pollination treatments than in the open-pollinated treatment. However, seed mass was higher in both open pollinated and outcross pollination treatments compared with hand self-pollinated. We found greater female reproductive success for taller flowering stems that simultaneously benefited from increased pollination and reduced seed predation. These studies suggest that this species is under strong reinforcing selection to increase allocation to flowering stem height. Our results may help

  18. Responses to simulated nitrogen deposition by the neotropical epiphytic orchid Laelia speciosa

    PubMed Central

    Díaz-Álvarez, Edison A.; Lindig-Cisneros, Roberto

    2015-01-01

    Potential ecophysiological responses to nitrogen deposition, which is considered to be one of the leading causes for global biodiversity loss, were studied for the endangered endemic Mexican epiphytic orchid, Laelia speciosa, via a shadehouse dose-response experiment (doses were 2.5, 5, 10, 20, 40, and 80 kg N ha−1 yr−1) in order to assess the potential risk facing this orchid given impending scenarios of nitrogen deposition. Lower doses of nitrogen of up to 20 kg N ha yr−1, the dose that led to optimal plant performance, acted as fertilizer. For instance, the production of leaves and pseudobulbs were respectively 35% and 36% greater for plants receiving 20 kg N ha yr−1 than under any other dose. Also, the chlorophyll content and quantum yield peaked at 0.66 ± 0.03 g m−2 and 0.85 ± 0.01, respectively, for plants growing under the optimum dose. In contrast, toxic effects were observed at the higher doses of 40 and 80 kg N ha yr−1. The δ13C for leaves averaged −14.7 ± 0.2‰ regardless of the nitrogen dose. In turn, δ15N decreased as the nitrogen dose increased from 0.9 ± 0.1‰ under 2.5 kg N ha−1yr−1 to −3.1 ± 0.2‰ under 80 kg N ha−1yr−1, indicating that orchids preferentially assimilate NH4+ rather than NO3− of the solution under higher doses of nitrogen. Laelia speciosa showed a clear response to inputs of nitrogen, thus, increasing rates of atmospheric nitrogen deposition can pose an important threat for this species. PMID:26131375

  19. Desiccation tolerance, longevity and seed-siring ability of entomophilous pollen from UK native orchid species

    PubMed Central

    Marks, Timothy R.; Seaton, Philip T.; Pritchard, Hugh W.

    2014-01-01

    Background and Aims Pollinator-limited seed-set in some terrestrial orchids is compensated for by the presence of long-lived flowers. This study tests the hypothesis that pollen from these insect-pollinated orchids should be desiccation tolerant and relatively long lived using four closely related UK terrestrial species; Anacamptis morio, Dactylorhiza fuchsii, D. maculata and Orchis mascula. Methods Pollen from the four species was harvested from inflorescences and germinated in vitro, both immediately and also after drying to simulate interflower transit. Their tolerance to desiccation and short-term survival was additionally assessed after 3 d equilibration at a range of relative humidities (RHs), and related to constructed sorption isotherms (RH vs. moisture content, MC). Ageing of D. fuchsii pollen was further tested over 2 months against temperature and RH, and the resultant survival curves were subjected to probit analysis, and the distribution of pollen death in time (σ) was determined. The viability and siring ability, following artificial pollinations, were determined in D. fuchsii pollen following storage for 6 years at –20 °C. Key Results The pollen from all four species exhibited systematic increases in germinability and desiccation tolerance as anthesis approached, and pollen from open flowers generally retained high germinability. Short-term storage revealed sensitivity to low RH, whilst optimum survival occurred at comparable RHs in all species. Similarly, estimated pollen life spans (σ) at differing temperatures were longest under the dry conditions. Despite a reduction in germination and seeds per capsule, long-term storage of D. fuchsii pollen did not impact on subsequent seed germination in vitro. Conclusions Substantial pollen desiccation tolerance and life span of the four entomophilous orchids reflects a resilient survival strategy in response to unpredictable pollinator visitation, and presents an alternative approach to germplasm

  20. Weak trophic links between a crab-spider and the effective pollinators of a rewardless orchid

    NASA Astrophysics Data System (ADS)

    Quintero, Carolina; Corley, Juan C.; Aizen, Marcelo A.

    2015-01-01

    Sit and wait predators hunting on flowers are considered to be exploiters of plant-pollinator mutualisms. Several studies have shown that plant-pollinator interactions can be highly susceptible to the impact of a third trophic level, via consumptive (direct) and non-consumptive (indirect) effects that alter pollinator behavior and, ultimately, plant fitness. However, most flowering plants attract a wide array of flower visitors, from which only a subset will be effective pollinators. Hence, a negative effect of an ambush predator on plant fitness should be expected only when: (i) the effective pollinators are part of the predators' diet and/or (ii) the non-consumptive effects of predator presence (e.g. dead prey) alter the behavior of effective pollinators and pollen movement among individual plants. We analyzed the direct and indirect effects of a crab-spider (Misumenops pallidus), on the pollination and reproductive success of Chloraea alpina, a Patagonian rewardless orchid. Our results indicate that most of the flower visitors do not behave as effective pollinators and most effective pollinators were not observed as prey for the crab-spider. In terms of non-consumptive effects, inflorescences with and without spiders and/or dead-prey did not vary the frequency of flower visitors, nor pollinia removal or deposition. Hence, it is not surprising that M. pallidus has a neutral effect on pollinia removal and deposition as well as on fruit and seed set. Similar to other rewardless orchids, the low reproductive success of C. alpina (∼6% fruit set) was associated with the limited number of visits by effective pollinators. Negative top-down effects of a flower-visitor predator on plant pollination may not be anticipated without studying the direct and indirect effects of this predator on the effective pollinators. In pollination systems where effective pollinators visited flowers erratically, such as in deceptive orchids, we expect weak or no effect of predators on

  1. Responses to simulated nitrogen deposition by the neotropical epiphytic orchid Laelia speciosa.

    PubMed

    Díaz-Álvarez, Edison A; Lindig-Cisneros, Roberto; de la Barrera, Erick

    2015-01-01

    Potential ecophysiological responses to nitrogen deposition, which is considered to be one of the leading causes for global biodiversity loss, were studied for the endangered endemic Mexican epiphytic orchid, Laelia speciosa, via a shadehouse dose-response experiment (doses were 2.5, 5, 10, 20, 40, and 80 kg N ha(-1) yr(-1)) in order to assess the potential risk facing this orchid given impending scenarios of nitrogen deposition. Lower doses of nitrogen of up to 20 kg N ha yr(-1), the dose that led to optimal plant performance, acted as fertilizer. For instance, the production of leaves and pseudobulbs were respectively 35% and 36% greater for plants receiving 20 kg N ha yr(-1) than under any other dose. Also, the chlorophyll content and quantum yield peaked at 0.66 ± 0.03 g m(-2) and 0.85 ± 0.01, respectively, for plants growing under the optimum dose. In contrast, toxic effects were observed at the higher doses of 40 and 80 kg N ha yr(-1). The δ (13)C for leaves averaged -14.7 ± 0.2‰ regardless of the nitrogen dose. In turn, δ (15)N decreased as the nitrogen dose increased from 0.9 ± 0.1‰ under 2.5 kg N ha(-1)yr(-1) to -3.1 ± 0.2‰ under 80 kg N ha(-1)yr(-1), indicating that orchids preferentially assimilate NH4 (+) rather than NO3 (-) of the solution under higher doses of nitrogen. Laelia speciosa showed a clear response to inputs of nitrogen, thus, increasing rates of atmospheric nitrogen deposition can pose an important threat for this species. PMID:26131375

  2. Uptake of ant-derived nitrogen in the myrmecophytic orchid Caularthron bilamellatum

    PubMed Central

    Gegenbauer, Christian; Mayer, Veronika E.; Zotz, Gerhard; Richter, Andreas

    2012-01-01

    Background and Aims Mutualistic ant–plant associations are common in a variety of plant families. Some myrmecophytic plants, such as the epiphytic orchid Caularthron bilamellatum, actively form hollow structures that provide nesting space for ants (myrmecodomatia), despite a substantial loss of water-storage tissue. This study aimed at assessing the ability of the orchid to take up nitrogen from ant-inhabited domatia as possible trade-off for the sacrifice of potential water storage capacity. Methods Nitrogen uptake capabilities and uptake kinetics of 15N-labelled compounds (NH4+, urea and l -glutamine) were studied in field-grown Caularthron bilamellatum plants in a tropical moist forest in Panama. Plants were either labelled directly, by injecting substrates into the hollow pseudobulbs or indirectly, by labelling of the associated ants in situ. Key Results Caularthron bilamellatum plants were able to take up all tested inorganic and organic nitrogen forms through the inner surface of the pseudobulbs. Uptake of NH4+ and glutamine followed Michaelis–Menten kinetics, but urea uptake was not saturable up to 2 mm. 15N-labelled compounds were rapidly translocated and incorporated into vegetative and reproductive structures. By labelling ants with 15N in situ, we were able to prove that ants transfer N to the plants under field conditions. Conclusions Based on 15N labelling experiments we were able to demonstrate, for the first time, that a myrmecophytic orchid is capable of actively acquiring different forms of nitrogen from its domatia and that nutrient flux from ants to plants does indeed occur under natural conditions. This suggests that beyond anti-herbivore protection host plants benefit from ants by taking up nitrogen derived from ant debris. PMID:22778148

  3. Symbiotic seed germination and protocorm development of Aa achalensis Schltr., a terrestrial orchid endemic from Argentina.

    PubMed

    Sebastián, Fracchia; Vanesa, Silvani; Eduardo, Flachsland; Graciela, Terada; Silvana, Sede

    2014-01-01

    Aa achalensis is an endangered terrestrial orchid endemic from Argentina. In vitro symbiotic seed germination was evaluated for its propagation. Five different fungal strains were isolated from this species: two Rhizoctonia-like related to Thanatephorus cucumeris and three ascomicetaceous fungi belonging to Phialophora graminicola and one to an uncultured Pezizaceae. All five isolates promoted seed germination being one T. cucumeris strain the most effective. After 16 weeks of growth, 30% of A. achalensis protocorms developed until seedlings with two/four leaves in this treatment. These findings open an opportunity to the knowledge and preservation of this species. PMID:23780616

  4. [Visitation of orchid by Melipona capixaba Moure & Camargo (Hymenoptera: Apidae), bee threatened with extinction].

    PubMed

    Resende, Helder C; Barros, Fábio de; Campos, Lúcio A O; Fernandes-Salomão, Tânia M

    2008-01-01

    The stingless bee Melipona capixaba Moure & Camargo is a species restricted to the Atlantic forest in the Domingos Martins, Conceição do Castelo, Venda Nova do Imigrante and Afonso Cláudio County, in the Espírito Santo State, Brazil. Despite its cological importance as pollinator few studies have examined the ecology and biology of this bee. This note relates a case of the M. capixaba workers carrying pollinarium attached to the scuttellum. The pollinaria were identified as belonging to the orchid subtribe Maxillariinae species possibly of the genus Maxillaria sensu lato or Xylobium. PMID:19061051

  5. Golden mean renormalization for a generalized Harper equation: The Ketoja-Satija orchid

    NASA Astrophysics Data System (ADS)

    Mestel, B. D.; Osbaldestin, A. H.

    2004-12-01

    We provide a rigorous analysis of the fluctuations of localized eigenstates in a generalized Harper equation with golden mean flux and with next-nearest-neighbor interactions. For next-nearest-neighbor interaction above a critical threshold, these self-similar fluctuations are characterized by orbits of a renormalization operator on a universal strange attractor, whose projection was dubbed the "orchid" by Ketoja and Satija [Phys. Rev. Lett. 75, 2762 (1995)]. We show that the attractor is given essentially by an embedding of a subshift of finite type, and give a description of its periodic orbits.

  6. An overview of the Phalaenopsis orchid genome through BAC end sequence analysis

    PubMed Central

    2011-01-01

    Background Phalaenopsis orchids are popular floral crops, and development of new cultivars is economically important to floricultural industries worldwide. Analysis of orchid genes could facilitate orchid improvement. Bacterial artificial chromosome (BAC) end sequences (BESs) can provide the first glimpses into the sequence composition of a novel genome and can yield molecular markers for use in genetic mapping and breeding. Results We used two BAC libraries (constructed using the BamHI and HindIII restriction enzymes) of Phalaenopsis equestris to generate pair-end sequences from 2,920 BAC clones (71.4% and 28.6% from the BamHI and HindIII libraries, respectively), at a success rate of 95.7%. A total of 5,535 BESs were generated, representing 4.5 Mb, or about 0.3% of the Phalaenopsis genome. The trimmed sequences ranged from 123 to 1,397 base pairs (bp) in size, with an average edited read length of 821 bp. When these BESs were subjected to sequence homology searches, it was found that 641 (11.6%) were predicted to represent protein-encoding regions, whereas 1,272 (23.0%) contained repetitive DNA. Most of the repetitive DNA sequences were gypsy- and copia-like retrotransposons (41.9% and 12.8%, respectively), whereas only 10.8% were DNA transposons. Further, 950 potential simple sequence repeats (SSRs) were discovered. Dinucleotides were the most abundant repeat motifs; AT/TA dimer repeats were the most frequent SSRs, representing 253 (26.6%) of all identified SSRs. Microsynteny analysis revealed that more BESs mapped to the whole-genome sequences of poplar than to those of grape or Arabidopsis, and even fewer mapped to the rice genome. This work will facilitate analysis of the Phalaenopsis genome, and will help clarify similarities and differences in genome composition between orchids and other plant species. Conclusion Using BES analysis, we obtained an overview of the Phalaenopsis genome in terms of gene abundance, the presence of repetitive DNA and SSR markers

  7. Virus-induced gene silencing unravels multiple transcription factors involved in floral growth and development in Phalaenopsis orchids

    PubMed Central

    Hsieh, Ming-Hsien; Pan, Zhao-Jun; Lai, Pei-Han; Lu, Hsiang-Chia; Yeh, Hsin-Hung; Hsu, Chia-Chi; Wu, Wan-Lin; Chung, Mei-Chu; Wang, Shyh-Shyan; Chen, Wen-Huei; Chen, Hong-Hwa

    2013-01-01

    Orchidaceae, one of the largest angiosperm families, has significant commercial value. Isolation of genes involved in orchid floral development and morphogenesis, scent production, and colouration will advance knowledge of orchid flower formation and facilitate breeding new varieties to increase the commercial value. With high-throughput virus-induced gene silencing (VIGS), this study identified five transcription factors involved in various aspects of flower morphogenesis in the orchid Phalaenopsis equestris. These genes are PeMADS1, PeMADS7, PeHB, PebHLH, and PeZIP. Silencing PeMADS1 and PebHLH resulted in reduced flower size together with a pelaloid column containing petal-like epidermal cells and alterations of epidermal cell arrangement in lip lateral lobes, respectively. Silencing PeMADS7, PeHB, and PeZIP alone resulted in abortion of the first three fully developed flower buds of an inflorescence, which indicates the roles of the genes in late flower development. Furthermore, double silencing PeMADS1 and PeMADS6, C- and B-class MADS-box genes, respectively, produced a combinatorial phenotype with two genes cloned in separate vectors. Both PeMADS1 and PeMADS6 are required to ensure the normal development of the lip and column as well as the cuticle formation on the floral epidermal cell surface. Thus, VIGS allows for unravelling the interaction between two classes of MADS transcription factors for dictating orchid floral morphogenesis. PMID:23956416

  8. Solitary invasive orchid bee outperforms co-occurring native bees to promote fruit set in an invasive Solanum.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Little is known about the potential effects of naturalized solitary or semi-social bees on the environment. We took advantage of the recent naturalization of an orchid bee, Euglossa viridissima, in southern Florida to study the effects of this semi-social bee on reproduction of Solanum torvum, an in...

  9. Factors affecting reproductive success in three entomophilous orchid species in Hungary.

    PubMed

    Vojtkó, Anna E; Sonkoly, Judit; Lukács, Balázs András; Molnár V, Attila

    2015-06-01

    The reproductive success of orchids is traditionally estimated by determining the fruit-set of individuals. Here, we investigated both the fruit and the seed production of three orchid species and the factors that may affect individual fruit-set, like pollination strategy, individual traits or the annual amount of precipitation. The species [Dactylorhiza sambucina (L.) Soó, Dactylorhiza majalis (Rchb.) P. F. Hunt & Summerhayes and Platanthera bifolia (L.) L. C. M. Richard] were studied in three consecutive years (2010-2012) in the Bükk Mountains, Hungary. All three species were proved to be non-autogamous by a bagging experiment. Data analyses showed significant differences between seed numbers but not between fruit-sets of species. There was no statistical difference in individual reproductive success between wet and dry years, however, the effect of the annual amount of precipitation is significant on the population level. Comparison of published fruit-set data revealed accordance with our results in P. bifolia, but not in D. sambucina and D. majalis. We assume that the surprisingly high fruit-set values of the two Dactylorhiza species may be due to the fact that the pollination crisis reported from Western European countries is not an actual problem in the Bükk Mountains, Hungary. PMID:26081278

  10. Pollinator specificity drives strong prepollination reproductive isolation in sympatric sexually deceptive orchids.

    PubMed

    Whitehead, Michael R; Peakall, Rod

    2014-06-01

    Few studies have quantified the full range of pre- and postzygotic barriers that limit introgression between closely related plant species. Here, we assess the strength of four isolating mechanisms operating between two morphologically similar and very closely related sympatric orchid taxa, Chiloglottis valida and C. aff. jeanesii. Each taxon sexually attracts its specific wasp pollinator via distinct floral volatile chemistry. Behavioral experiments with flowers and synthetic versions of their floral volatiles confirmed that very strong pollinator isolation is mediated by floral odor chemistry. However, artificially placing flowers of the two taxa in contact proximity revealed the potential for rare interspecific pollination. Although we found hybrid vigor in F1 hybrids produced by hand-crossing, genetic analysis at both nuclear and chloroplast loci showed significant and moderate-to-strong genetic differentiation between taxa. A Bayesian clustering method for the detection of introgression at nuclear loci failed to find any evidence for hybridization across 571 unique genotypes at one site of sympatry. Rather than inhibiting gene flow, postpollination barriers surveyed here show no contribution to overall reproductive isolation. This demonstrates the primacy of pollinators in maintaining species boundaries in these orchids, which display one of the strongest known examples of prepollination floral isolation. PMID:24527666