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Dissertations / Theses on the topic 'Orchids. Orchids'

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Published: 4 June 2021
Last updated: 16 February 2022

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1

Hughes, Oliver Thomas Wesley. "Orchid-mycorrhiza relationships : propagation of terrestrial and epiphytic orchids from seed." Thesis, Manchester Metropolitan University, 2018. http://e-space.mmu.ac.uk/621969/.

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Many orchids are rare and endangered due to habitat loss, degradation and human interference. This thesis aims to improve our understanding of orchid-mycorrhiza relationships and optimise methods for successful in vitro germination and development of terrestrial and epiphytic orchids. The research undertaken advances our understanding of orchids and has applications for conservation and horticulture. Fungal specificity plays a key role in orchid distribution and the colonisation of habitats. This was investigated in the Australian terrestrial orchid, Microtis media R. Br. in Chapter 2. Experiments demonstrated low fungal specificity in germination in vitro, although later development was more specific, with one fungus inducing protocorm development through to adult plants. Fungal compatibility was tested in several Eurasian terrestrial orchids in Chapter 3. Varying degrees of specificity were observed, with Anacamptis morio (L.) R.M.Bateman, Pridgeon & M.W.Chase and Dactylorhiza incarnata (L.) Soό displaying low fungal specificity whereas Serapias spp. were more specific. Orchids are commonly propagated without fungi using asymbiotic media. Asymbiotic and symbiotic methods were compared in two Eurasian terrestrial orchids in Chapter 4. In both cases, symbiotic methods resulted in higher germination and development. In Anacamptis laxiflora (Lam.) R. M. Bateman, Pridgeon & M. W. Chase, successful seedling establishment ex vitro was only achieved with symbiotic seedlings. Following this study, the effect of substrate rugosity and complexity on germination in asymbiotic and symbiotic culture of two Eurasian terrestrial orchids was investigated in Chapter 5. Substrate rugosity had a positive effect on germination and development in symbiotic cultures of A. morio and both asymbiotic and symbiotic cultures of Dactylorhiza purpurella (T.Stephenson & T.A.Stephenson) Soó. The subtribe Pleurothallidinae is one of the largest in the Orchidaceae and little is known about their propagation requirements. A number species from different genera within this group were tested with different asymbiotic media and fungi isolated from plants in an ex situ collection in Chapter 6. Germination was highest with two fungal strains but development of plantlets only occurred on asymbiotic media. Ex situ study and propagation of myco-heterotrophic orchids poses some difficulties. A novel method is presented, using microcosms for the initiation of tripartite symbioses with tree seedlings, fungi and orchids in Chapter 7. Associations between tree seedlings, fungi and orchid seed were observed. Germination was not achieved with seed of Neottia nidus-avis (L.) Rich. The method provides a basis for further development with applications in a range of ecological studies.
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2

Yam, Tim-wing. "Conservation, ecology and propagation of the wild orchids of Hong Kong /." [Hong Kong : University of Hong Kong], 1988. http://sunzi.lib.hku.hk/hkuto/record.jsp?B1243873X.

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3

Tsui, Yuk-chun Prisca. "Conservation and propagation of wild orchids in Hong Kong /." [Hong Kong : University of Hong Kong], 1992. http://sunzi.lib.hku.hk/hkuto/record.jsp?B13226290.

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4

Shan, Xuechan. "Fungal associations and aspects of seed biology of some orchids of Hong Kong /." Hong Kong : University of Hong Kong, 1999. http://sunzi.lib.hku.hk/hkuto/record.jsp?B20566670.

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5

Liu, Bing. "Germination studies in terrestrial orchids." Thesis, University of Leeds, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.303461.

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6

Yuh, Seon Hee. "Cloning genes differentially expressed in freezing tolerant orchids." Virtual Press, 1996. http://liblink.bsu.edu/uhtbin/catkey/1020165.

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Genes responsible for differences in gene regulation and expression in normal cells and freezing tolerant cells were identified using two related wintergreen orchid species, Aplectrum hyemale and Tipularia discolor. Changes in gene expression observed in field-collected tissues obtained from different seasons were compared as were changes observed in plants subjected to cold shock in a laboratory environmental chamber. In order to clone these differentially expressed genes which may confer photosynthesis cold tolerance, the recently developed technique, mRNA differential display was employed. Using this process, mRNA was isolated from the tissue and reverse transcribed to cDNAs, which were amplified using specific anchored 3' primers and various random 5' primers. The 50-100 bands resulting from specific primers were compared on denaturing polyacrylamide gels. Bands differently expressed were excised from the gel and purified. In the future, if partial sequence analysis indicates they may code important regulatory proteins, they will be used as probes to obtain full-length genes from a cDNA library for further characterization. This study provides an opportunity not only to obtain important regulatory genes in plants, but also to understand more about temperature regulated gene expression in orchids.
Department of Biology
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7

Barkman, Todd James. "Evolution of Dendrochilum subgenus Platyclinis section Eurybrachium investigated in a phylogenetic context /." Digital version accessible at:, 1998. http://wwwlib.umi.com/cr/utexas/main.

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8

Hart, Phoebe. "Orchids : intersex and identity in documentary." Queensland University of Technology, 2009. http://eprints.qut.edu.au/29712/.

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Orchids: Intersex and Identity in Documentary explores the creative practice challenges of working with bodies with intersex in the long-form auto/biographical documentary Orchids. Just as creative practice research challenges the dominant hegemony of quantitative and qualitative research, so does my creative work position itself as a nuanced piece, pushing the boundaries of traditional cultural studies theories, documentary film practice and creative practice method, through its distinctive distillation and celebration of a new form of discursive rupturing, the intersex voice.
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9

Wong, Kwong-chiu Alfred. "Conservation genetics of Hong Kong wild orchids /." Hong Kong : University of Hong Kong, 1998. http://sunzi.lib.hku.hk/hkuto/record.jsp?B2035793X.

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10

Kim, Bong-Suk. "Cloning of genes encoding desirable characteristics of dendrobium gatton 'sunray'." Virtual Press, 1995. http://liblink.bsu.edu/uhtbin/catkey/941349.

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Currently the breeding of desirable traits in orchid flowers is a lengthy and unpredictable process. A shortened breeding time and a more direct method of introducing specific genetic characteristics could be achieved if more information were available on the specific genes responsible for flower characteristics. In order to identify some of these genes, the genetic relationships between a hybrid, Dendrobium Gatton 'Sunray', and the parent species bred to produce it, D. chrysotoxum Lindley and D. pu/che//um Lindley were examined.Ball State UniversityMuncie, IN 47306These results were supported by Restriction Fragment Length Polymorphisms (RFLPs) observed following amplification of the Internal Transcribed Spacer (ITS) regions of the rDNAs.In order to clone genes responsible for specific flower characteristics, mRNA differential display was performed using total RNA isolated from the leaves, immature flowers, and mature flowers of the hybrid orchid and its two parents. Bands unique to D. Gatton 'Sunray' flower tissue, which were common to the hybrid and a single parent, were excised from a denaturing acrylamide gel. Four of the bands, which represented expressed genes determining inherited flower characteristics, were re-amplified, cloned, and three were sequenced. Partial sequence information obtained for two of the clones was used to search the GenBank database for homologous genes. One of the clones had sequence homology to plant 26S ribosomal genes and the other clone was homologous to sequences encoding regulatory proteins active during development (for example, the human retinoblastoma susceptibility gene or the Caenorhabditis e/egans cosmid R06F6 containing a serine/threonine protein kinase gene).
Department of Biology
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11

Petersen, Kellie. "Hybridizers and the Hybridized: Orchid Growing as Hybrid "Nature?"." Scholar Commons, 2018. https://scholarcommons.usf.edu/etd/7350.

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Orchid growing is a hobby that includes not only acquiring and caring for orchids, but also learning about the diverse care requirements of various orchids, attending meetings of orchid groups, having one’s orchids evaluated by American Orchid Society judges or being a judge, or even creating hybrids. In this way, orchid hobbyists compose a distinctive subculture (Hansen 2000). Yet the activity of orchid growing also forms a nexus between the non-human and the human, two categories that are often constructed as an opposing binary. This thesis focuses on how orchid growing represents both the embedded, institutionalized characteristic of the binary between the non-human and the human and how this binary is actively deconstructed; that is, orchid growers often reinforce this binary through positioning their orchids as a part of “nature” and also blur it by participating in the activity of orchid growing. Through observations of monthly meetings of two local orchid groups and affiliated events and walking tours of individual participants’ orchid growing spaces and semi-structured interviews with them, I show how orchid growing represents such a “hybrid” form of nature (Whatmore 2002). Specifically, the ways in which orchid growers appreciate the novelty of their orchids, care for them, and establish authenticity in orchid growing demonstrates the nuanced ways orchid growing forms a relationship with “nature.”
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12

Wong, Kwong-chiu Alfred, and 黃廣潮. "Conservation genetics of Hong Kong wild orchids." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B31221920.

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13

Marchione, Wesley A. "Pathogen resistance genes and proteins in orchids." Virtual Press, 2003. http://liblink.bsu.edu/uhtbin/catkey/1260625.

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To study resistance (R) genes that are expressed when Sophrolaeliacattleya Ginny Champion 'Riverbend' orchid tissue was infected with the tobacco mosaic virus (TMV0), a subtraction library of cDNA clones was previously constructed using mRNA isolated before and after infection (Shuck, unpublished). From 200 clones collected, 5 clones were randomly selected, DNA was isolated, and the cDNA insert was sequenced. These sequences were imported into BLAST to search for homology to other R genes. This search revealed clone 4A to have an 84% homology to a 54 nucleotide region from the Arabidopsis thaliana oligouridylate binding protein which is highly expressed and known to bind RNA Polymerase III transcripts and adenovirus associated RNAs. Further bioinformatics analysis was performed utilizing databases and analysis packages available on the Internet, software such as Vector NTI (Informax, Bethesda, MD), and manual searches. However, no additional domains or motifs indicative of pathogen resistance genes were located in any of the 5 clones. Subsequently, total proteins expressed at various time points following infection were examined on denaturing 5-20% gradient polyacrylamide gels stained with the ProteoSilver Plus TM silver stain kit (Sigma, St. Louis, MO) in order to examine the timing and duration of expression of proteins involved in TMV-O resistance. One protein of-18 kDa was highly expressed at 4 hr after infection that was not seen in the negative control. By 8 hr the band was no longer expressed, it was expressed again from 30 - 48 hr, but was not seen again in later time points. Finally, total mRNA isolated from pooled time points and subjected to in vitro translation indicated a reduction in translation products after infection, providing evidence of posttranscriptional gene silencing (PTGS) following TMV-O infection.
Department of Biology
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14

Darkwa, Alfred Anthony. "Growth and biochemistry of hardy European orchids." Thesis, University of Sussex, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.495011.

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15

Neiland, Mary Ruth Miller. "Reproductive ecology of British and Mediterranean orchids." Thesis, University of Aberdeen, 1994. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU072992.

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Factors contributing to the natural reproductive performance of flowers, plants and populations of British and Mediterranean Orchidaceae are considered. Reproductive success is found to be pollinator limited, with most European orchids failing to achieve their maximum potential within the season, particularly nectarless species. There is a consistent discrepancy in gender function, with many more pollinia being removed than returned, because of pollinator foraging behaviour. Patterns of insect visitation to orchids are influenced by inflorescence and labellum characters, such as floral spurs. Spurs vary in size and shape between species, and many are nectarless. Trichomes are often present on the inner surface, and may prolong insect visits. The principal orchid pollinators are all members of the Hymenoptera, Lepioptera and Diptera, which normally visit other plants for food. Co-occurring species can act in a facilitative way to maintain a band of local pollinator, and pollination of all species examined is found to be significantly associated with the presence of 1 or 2 key foreign species or a guild of such plants. Under conditions of infrequent pollination, various features of the European Orchidaceae act to maximise their reproductive success when pollination does occur. The flowers are found to be long-lived and remain receptive to additional pollinations which may lead to increased seed quantity and diversity. Pollen maintains viability for several week which prolongs the opportunity of insect transported pollinia to effect pollination. Break up of pollinia into smaller dispersal units increases the likelihood of widespread dispersal and reduces pollen wastage. Even the smallest pollen load is found to stimulate embryogenesis, but more seeds are set with larger loads. PL:O ratios of 2-3:1 are most commonly found, which should result in both maximal seed set and increased quality of the offspring. Furthermore, seed output is significantly associated with fruit set and average levels of capsule formation are consistently higher in nectariferous orchids than in nectarless ones. Most rare British orchids are nectarless, and are particularly vulnerable to environmental alterations which influence the floral composition of their habitat, and density and distribution of supporting species.
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16

Toscano, de Brito Antonio Luiz Viera. "Systematic studies in the subtribe Ornithocephalinae (Orchidaceae)." Thesis, University of Reading, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386911.

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17

Khayota, Beatrice N. "Systematics of the genus Ansellia Lindl. (Orchidaceae)." Thesis, University of Reading, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.283021.

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18

Ryan, Angela. "A phylogenetic assessment of Lycaste and Anguloa (Orchidaceae)." Thesis, University College London (University of London), 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.252249.

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19

Goldman, Douglas H. "Systematics of Calopogon and the tribe Arethuseae (Orchidaceae) /." Digital version accessible at:, 2000. http://wwwlib.umi.com/cr/utexas/main.

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20

Qamaruz-Zaman, Faridah. "Conservation genetics of rare and endangered British orchids." Thesis, University of Cambridge, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.621726.

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21

Chan, Man-chung. "Genetic diversity and relationships of spiranthes sinensis, S. spiralis, and S. hongkongensis (orchidaceae) as revealed by RAPD and cpDNA markers /." Hong Kong : University of Hong Kong, 1997. http://sunzi.lib.hku.hk/hkuto/record.jsp?B19324200.

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22

Bichsel, Rebecca Gayle. "Determining the nutritional requirements for optimizing flowering of the nobile dendrobium as a potted orchid." [College Station, Tex. : Texas A&M University, 2006. http://hdl.handle.net/1969.1/ETD-TAMU-1116.

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23

Tsui, Yuk-chun Prisca, and 徐玉珍. "Conservation and propagation of wild orchids in Hong Kong." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1992. http://hub.hku.hk/bib/B31210570.

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24

Saxon, Herbert. "The molecular biology of orchids : transformation by Agrobacterium Tumefaciens and DNA fingerprinting." Virtual Press, 1995. http://liblink.bsu.edu/uhtbin/catkey/941575.

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The work reported here was done at the Wheeler Orchid Collection and Species Bank and the Department of Biology at Ball State University. We have developed a research teaching program with two applied research goals: genetically transforming and DNA fingerprinting orchid tissue. As part of their molecular biology education, students have investigated the genetic transformation of orchids for mitigating viral symptoms and the identification of unknown orchids by DNA fingerprinting. In a second application of the technology, DNA fingerprinting has been used to determine evolutionary relationships and to quantify genetic diversity among orchids.This dissertation details the background and need for this project and the research that was done to start it. As the early work has, developed and students have added their contributions, the data have developed into two papers formatted for submission to scientific journals. They are included as results.The first is a project designed to insert exognenous DNA into orchid tissue. The soil microbe Agrobacterium tumefaciens causes crown-gall tumors to develop in its plant hosts by inserting DNA into their cells which then controls the biosynthesis of development-controlling hormones. A. tumefaciens which has been disarmed has been routinely used to bioengineer dicotyledonous plants but its use has been rare on monocotyledons. In this paper, we report that A. tumefaciens transformed embryonic orchid tissue and caused alteration in its normal developmental course.The second paper details the DNA fingerprinting of tissue from Aplectrum hymale, a terrestrial orchid native to this climate. Three populations of A. hymale have been sampled and DNA extracted from the tissue samples. RAPD primers were used to prime PCR amplifications of random sequences of the DNA and the amplified DNA was visualized by gel electrophoresis. Loci of the resulting bands were treated as potentially multiallelic gene loci and heterozygosity between and within subpopulations was calculated. We report that the three populations could be partially differentiated by this procedure and that the two populations located nearest to each other yielded the least between -ubpopulation heterozygosity. We report very high levels of genetic diversity between individuals within small subpopulations in spite of the fact that these subpopulations are considered to be primarily clonal in reproductive nature.
Department of Biology
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25

Powell, Martyn P. "Evolutionary ecology of neotropical orchids, with emphasis on Oncidiinae." Thesis, University of Reading, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.494102.

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This thesis investigates speciation in Neotropical orchids, with a focus on the subtribe Oncidiinae, which has undergone a dramatic radiation in the Neotropics. A near-complete species-level phylogeny of the Tolumnia clade (a subset of the Oncidiinae), comprising 47 of the 51 currently recognised species, based on multiple plastid (trnH-psbA, trnL-F, rps16) and nuclear DNA regions (ITS and ETS) provides a well resolved and robust framework from which to address questions about the evolutionary history of this group. It also permits the clarification of the taxonomic status of certain anomalous taxa, including the genus Amparoa which is found to be embedded within Rhynchostele. Significant levels of rate heterogeneity are observed between the lineages of this phylogenetic tree, and potential causes, both physiological and ecological, of these are examined, although no single causal factor is identified.
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26

Roberts, David Lesford. "Reproductive biology and conservation of the orchids of Mauritius." Thesis, Aberystwyth University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.367505.

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27

Chesselet, Pascale Claude Marcelle Henriette. "Systematic implications of leaf anatomy and palynology in the Disinae and Coryciinae (Orchidaceae)." Master's thesis, University of Cape Town, 1989. http://hdl.handle.net/11427/18698.

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Pollen morphology of 8 species (TEM), 86 species (SEM), and leaf anatomy of 62 species (LM), were surveyed in the Oisinae, Coryclinae and, as outgroup taxa, the Orchideae and Satyriinae. Characters extracted from observations made of leaf anatomy and pollen were analysed using cladistic methods, and assessed in relation to the present phylogeny of the group. Leaf anatomy data gave little phylogenetic information. Sclerification associated with vascular bundles was systematically useful. Pollen data served to resolve taxa at the subtribal level. Both data sets provided evidence of relationship for taxonomically problematic taxa. The Coryciinae are palynologically defined by a suite of synapomorphies, including a secondarily tectate exine structure, fasciculate massulae, and elongated tetrads with linear microspore configuration. Bibliography: pages 107-123.
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28

Yam, Tim-wing, and 任添榮. "Conservation, ecology and propagation of the wild orchids of HongKong." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1988. http://hub.hku.hk/bib/B31231731.

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29

Ackerman, Rodney Rex. "The effects of complex additives and growth regulators on the growth and clonal propagation of Phalaenopsis orchids." Virtual Press, 1988. http://liblink.bsu.edu/uhtbin/catkey/546145.

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The goal of this study was two fold, the first was to determine the effect of different basal medium formulationsand medium supplements (complex additives and growth hormones) on the development and growth rate of Phalaenopsis orchids, while the second goal was to find or develop an efficent method for the clonal propagation of Phalaenopsis orchids.MethodsThe first part of this study was further subdivided in to several phases; the first of these involved a comparative study of the germination of Phalaenopsis ovules on six different basal medium formulations and seven different sets of medium supplements. The second phase involved a comparative study of the development of Phalaenopsis protocorms on six different basal medium formulations and ninteen different sets of medium supplements. The third phase involved a comparative study of the growth of Phalaenopsis seedlings on six different basal medium formulations and twelve sets of medium supplements. The forth and final phase involved a comparative study of the development and growth of Phalaenopsis protocorms and seedlings on media containing varing concentrations and combinations of auxins and cytokinins. The second part of this study involved a comparative study designed-to determine the suitability of several sizes of axillary buds and plantlets for the clonal propagation of Phalaenopsis orchids and the modification of several procedures in an attempt to determine suitable explant material and procedures for the commercial clonal propagation of Phalaenopsis orchids.Results and DiscussionResults of this study indicated that of the basal medium formulations and medium supplements tested Modified Heller's salt base medium and to a lesser extent Modified Vacin and Went salt base medium supplemented with vitamin formulation 1 and Bactopeptone yielded the highest percent germination and development up to the seedling stage. At the seedling stage the growth rate of seedlings grown on media supplemented with banana homogenate nearly doubled the growth rate of the seedlings grown on all of the other medium supplementstested.Results of the second part of this study indicated that by modifying the procedures of Bouriquet, Broly, and Legrand (1982) the proliferation rate (shoots per plantlet) could be increased by a factor of two to eight. This can be translated into an increase from two to five shoots per plantlet per six weeks to an increase of eight shoots per plantlet per six weeks with a minimal mortality rate. With further modification of the procedure of Bouriquet, Broly, and Legrand (1982), other results indicated that it may be possible to increase to forty the number of shoots per plantlet produced per six week period.
Department of Biology
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30

Stewart, Scott L. "Integrated conservation of Florida Orchidaceae in the genera Habenaria and Spiranthes : model orchid conservation systems for the Americas /." View online, 2007. http://etd.fcla.edu/UF/UFE0021367/stewart_s.pdf.

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31

Devey, Dion Stuart. "MARC RecordSystematics and conservation of Mediterranean insect-mimicking orchids (Ophrys)." Thesis, University of Reading, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.494444.

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Historically, Ophrys morphological taxonomy and species delimitation have been controversial, with treatments inferring from 16 species plus 34 subspecies to as many as 252 species forming 32 complexes. Highly variable, yet possibly convergent, morphologies and paucity of sequence variation have hindered production of a robust phylogenetic framework. This project generated phylogenies and ordinations from nuclear and plastid DNA sequencing, amplified fragment length polymorphism (AFLP) and morphometric data, with the ultimate aims of producing a robust framework as a basis for more rigorous species delimitation and conservation recommendations for the genus. The project also elucidates genetic and morphological relationships within Ophrys section Ophrys, and within the 0. fuciflora and 0. sphegodes aggregates, and assesses the congruence between these contrasting datasets.
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32

Nam, Kam-shing, and 藍金成. "Conservation of Hong Kong wild orchids by leaf tip culture." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1995. http://hub.hku.hk/bib/B31212591.

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Oscar, Alejandro Perez Escobar [Verfasser], and Marc [Akademischer Betreuer] Gottschling. "Molecular phylogenetics, evolution of sexual systems and historical biogeography of Darwin's favourite orchids (Catasetinae) and Swan orchids (Cycnoches Lindl.) / Perez Escobar Oscar Alejandro. Betreuer: Marc Gottschling." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2016. http://d-nb.info/1110749163/34.

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34

Quiroga, Fernandez Ana Isabel, and Yunfeng Wang. "Female Entrepreneurs - Orchids in the Forest : Conditions for female start-ups." Thesis, Linnéuniversitetet, Ekonomihögskolan, ELNU, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-12435.

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The last century has witnessed blooming achievements of females as rising workforce in modern society. With their active participation in business world recently, female entrepreneurship research has caught extensive attention globally, not only from academic field, but also from market entities, policy makers, social activists, as well as broad masses, concerning the social and economic contribution of female-started entreprises. Current studies within this topic concentrate on two issues: the difference between male and female entrepreneurs; demographic research for certain countries, regions, or industries. Following a qualitative research approach, this thesis applies implementations of actors view and grounded theory. With the purpose to create in-depth business knowledge, a well-structured empirical exploration is conducted mainly through theoretical sensibility acquisition, secondary data collection and face-to-face dialogues focusing on the issue of conditions for female entrepreneurs to start up and to develop a business.The researchers share their comprehensive (from both micro and macro perspective) understanding about this subject: There is no such a formula of necessary conditions existing. Female entrepreneurs need to define them according to the type of the ventures they establish and the demand for their projected growth, pursue them by taking actions instead of waiting for all conditions to be ready. The forthcoming female economy brings millions of opportunities that favor female entrepreneurs to start up enterprises, despite the current situation where they have not received effective supports that they deserve. In the end, the researchers create a new term „femesh‟ to conclude their findings and their anticipation for the future blossom of female entrepreneurs. Especially, the academic research process is described as an exploration adventure for searching orchids in the forest, together with the romantic writing style of the authors, bringing enjoyable readability without losing its preciseness, accuracy and logic as an academic research.
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35

Collins, Margaret Thora. "Factors affecting the recovery of orchids in a post-mining landscape." University of Western Australia. School of Earth and Geographical Sciences, 2008. http://theses.library.uwa.edu.au/adt-WU2008.0022.

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[Truncated abstract] Currently, Alcoa World Alumina Australia (Alcoa) mines and undertakes procedures to rehabilitate approximately 550 ha of jarrah forest each year at two open-cut bauxite mines in South-West Western Australia. Alcoa aims to establish a self-sustaining jarrah forest ecosystem that maintains the functions of the landscape prior to mining, including biodiversity, on areas that have been mined for bauxite. Indigenous terrestrial orchids form a significant proportion of the indigenous geophytic plant species that either fail to colonise rehabilitated areas or do so very slowly. Terrestrial orchids are considered to be particularly sensitive to competition from weeds and disturbance, which combined with the obligate nature of the orchid-mycorrhizal fungus association suggests that orchids would colonise rehabilitation areas only when both microhabitat sites and soil microflora have established. Occurrence of certain orchids may therefore be expected to be useful as indicators of ecosystem health, the success of vegetation establishment and the recovery of edaphic conditions suitable for orchid mycorrhizal fungi. Vegetation surveys were undertaken to compare orchid species richness and population size of a chrono-sequence of rehabilitation areas with adjacent unmined forest. ... Orchid taxa present in each vegetation assemblage were generally not exclusive to these assemblages, with the following broad exclusions: D. bracteata was found only in species assemblages associated with rehabilitation areas; and Eriochilus sp. and T. crinita were found only in species assemblages associated with unmined forest. No single orchid species appears to be an indicator of ecosystem recovery. However, the presence of populations of C. flava, P. sp. crinkled leaf (G.J.Keighery 13426) or P. recurva in combination with the absence of the disturbance opportunist orchid taxa D. bracteata and M. media appears to be a measure of the maturity of the rehabilitation vegetation. Orchid species richness and clonal orchid population size were correlated with changes in vegetation structure, but apart from the absence of orchids in 1 year old rehabilitation areas, these orchid population characteristics did not show any direct relationship with rehabilitation age or vegetation maturity. Only two orchid taxa appeared to have potential as indicators of vegetation characteristics: T. crinita as an indicator of undisturbed jarrah forest; and D. bracteata as an indicator of disturbed ecosystems. The results of this study suggest that most jarrah forest orchid taxa will readily colonise the post bauxite mining landscape, but that the unassisted colonisation by recalcitrant orchid taxa may be a prolonged process. It is recommended that field-based transplantation and/or seeding trials be undertaken with these recalcitrant taxa to determine if these procedures will enhance recruitment. The results of this work have applications not only in the management of post-mining landscapes but also in vegetation monitoring and conservation work in Western Australia and elsewhere.
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Lukasiewicz, Magdalena J. "Maternal investment, pollination efficiency and pollen, ovule ratios in Alberta orchids." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ48023.pdf.

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37

Schweiger, Julienne M. I. [Verfasser], and Gerhard [Akademischer Betreuer] Gebauer. "Partial mycoheterotrophy in orchids / Julienne M.-I. Schweiger ; Betreuer: Gerhard Gebauer." Bayreuth : Universität Bayreuth, 2019. http://d-nb.info/117852602X/34.

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38

Morris, Lynda M. "An analysis of the population genetics of orchids using protein electrophoresis." Thesis, University of Essex, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.397368.

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39

Stökl, Johannes. "Pollinator driven radiation in sexually deceptive orchids of the genus Ophrys." [S.l. : s.n.], 2007. http://nbn-resolving.de/urn:nbn:de:bsz:289-vts-60423.

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40

Hutchinson, Chad M. "Agrobacterium tumefaciens mediated transformation of orchid tissue with the sense and antisense coat protein genes from the odontoglossum ringspot virus." Virtual Press, 1992. http://liblink.bsu.edu/uhtbin/catkey/834608.

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This research was an attempt to use a dicot transformation vector to transform a monocot. The initial purpose of this thesis was to transform orchids with the sense and antisense coat protein genes from the Odontoglossum ringspot virus (ORSV) in an effort to mitigate viral symptoms in transgenic plants using the transformation vector, Agrobacterium tumefaciens. However, it soon became apparent that much time would be needed to develop a transformation protocol. The transformation vectors used included the Agrobacterium tumefaciens disarmed strain LBA4404 with the binary plasmid pB1121, the disarmed strain At699 with the binary plasmid pCNL65, and the wild-type strain Chry5. The marker gene on the binary plasmids of both disarmed strains was p-glucuronidase (GUS).Several transformation protocols were used in an effort to determine if this transformation system would work on orchids. Transformation was not achieved even though a number of experimental conditions were varied. These included using two different types of orchid tissue, callus and protocorms; using two different species of orchids, Cattleya Chocolate Drop x Cattleytonia Kieth Roth and Cymbidium maudidum; varying the time the plant tissue was exposed to the bacteria from 1 hour to 96 hours; performing experiments with and without the wound signal molecule acetosyringone; and exposing the tissue to the virulent strains of A. tumefaciens mentioned previously.This research also developed GUS assay conditions necessary to decrease the number of false positives due to bacterial contamination. These conditions included chloramphenicol in the GUS assay buffer.
Department of Biology
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41

Hollick, Penelope Sarah. "Mycorrhizal specificity in endemic Western Australian terrestrial orchids (tribe Diurideae) : implications for conservation /." Hollick, Penelope Sarah (2004) Mycorrhizal specificity in endemic Western Australian terrestrial orchids (tribe Diurideae): implications for conservation. PhD thesis, Murdoch University, 2004. http://researchrepository.murdoch.edu.au/103/.

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The specificity of fungal isolates from endemic Western Australian orchid species and hybrids in the tribe Diurideae was investigated using symbiotic seed germination and analysis of the fungal DNA by amplified fragment length polymorphism (AFLP). The distribution of the fungal isolates in the field was also assessed using two different seed baiting techniques. The information from these investigations is essential for developing protocols for reintroduction and translocation of orchid species. Two groups of orchids in the tribe Diurideae were studied. Firstly, a number of Caladenia species, their natural hybrids and close relatives from the southwest of Western Australia were selected because orchid species from the genus Caladenia are considered to have among the most specific mycorrhizal relationships known in the orchid family ? an ideal situation for the investigation of mycorrhizal specificity. Secondly, species of Drakaea and close relatives, from the southwest of Western Australia and elsewhere in Australia, which are never common in nature and occur in highly specialised habitats, were selected to investigate the influence of habitat on specificity. Seed from the common species Caladenia arenicola germinated on fungal isolates from adult plants of both C. arenicola and its rare and endangered relative C. huegelii, while seed from C. huegelii only germinated on its own fungal isolates. The AFLP analysis grouped the fungal isolates into three categories: nonefficaceous fungi, C. huegelii type fungi, and C. arenicola type fungi. The group of C. huegelii type fungi included some fungal isolates from C. arenicola. An analysis of the AFLP fingerprints of C. arenicola fungal isolates from different collection locations showed that some, but not all, populations were genetically distinct, and that one population in particular was very variable. Despite being thought to have very specific mycorrhizal relationships, Caladenia species hybridise frequently and prolifically in nature, often forming self-perpetuating hybrid lineages. Five natural hybrids within Caladenia and its closest relatives were investigated. Symbiotic cross-germination studies of parental and hybrid seed on fungi from the species and the naturally occurring hybrids were compared with AFLP analyses of the fungal isolates to answer the question of which fungi the hybrids use. The germination study found that, while hybrid seeds can utilise the fungi from either parental species under laboratory conditions, it is likely that the natural hybrids in situ utilise the fungus of only one parental species. Supporting these observations, the AFLP analyses indicated that while the parental species always possessed genetically distinct fungal strains, the hybrids may share the mycorrhizal fungus of one parental species or possess a genetically distinct fungal strain which is more closely related to the fungus of one parental species than the other. The work on Caladenia hybrids revealed that C. falcata has a broadly compatible fungus that germinated seeds of C. falcata, the hybrid C. falcata x longicauda, and species with different degrees of taxonomic affinity to C. falcata. In general, germination was greater from species that were more closely related to C. falcata: seeds from Caladenia species generally germinated well on most C. falcata isolates; species from same subtribe (Caladeniinae) germinated well to the stage of trichome development on only some of the fungal isolates and rarely developed further; and seeds from species from different subtribes (Diuridinae, Prasophyllinae, Thelymitrinae) or tribes (Orchideae, Cranichideae) either germinated well to the stage of trichome development but did not develop further, or did not germinate at all. The AFLP analysis of the fungal isolates revealed that the fungi from each location were genetically distinct. In situ seed baiting was used to study the introduction, growth and persistence of orchid mycorrhizal fungi. A mycorrhizal fungus from Caladenia arenicola was introduced to sites within an area from which the orchid and fungus were absent, adjacent to a natural population of C. arenicola. In the first growing season, the fungus grew up to 50 cm from its introduction point, usually persisted over the summer drought into the second season and even into the third season, stimulating germination and growth to tuber formation of the seeds in the baits. Watering the inoculated areas significantly increased seed germination. Mycorrhizal relationships in Drakaeinae were less specific than in Caladeniinae. A study of the species Spiculaea ciliata revealed that this species, when germinated symbiotically, develops very rapidly and has photosynthetic protocorms, unlike all other members of the Drakaeinae. An AFLP analysis of the fungal isolates of this species grouped the isolates according to whether they had been isolated from adult plants or reisolated from protocorms produced in vitro. Isolates were genetically distinct when compared before germination and after reisolation. A cross-species symbiotic germination study of seeds of three Drakaea species and one Paracaleana species against fungal isolates from the same species and several other Drakaeinae species revealed lower specificity in this group than previously thought. A number of fungal isolates from Drakaea and Paracaleana species germinated two or more seed types, while all seed types germinated on fungal isolates from other species and the seed of Drakaea thynniphila germinated to some extent on every fungal isolate tested. An AFLP analysis of the Drakaeinae fungal isolates supported this information, revealing little genetic differentiation between the fungi of different orchid species. An ex situ seed baiting technique was used to examine the role of mycorrhizal fungi in microniche specialisation in the narrow endemic Drakaea. Soil samples from within and outside two Drakaea populations were tested for germination of the relevant seed types. In both cases, germination was significantly higher on soil samples from within than outside the populations, suggesting that the relevant mycorrhizal fungi may be restricted to the same microniches as the Drakaea species. The presence of similar fungi at distant, disjunct locations may be related to the extreme age and geological stability of the Western Australian landscape. The information from these investigations is essential for developing protocols for reintroduction and translocation of orchid species. It appears that the mycorrhizal relationships in these groups of orchids are not as specific as was previously thought. For reintroduction work, a broad sampling strategy is necessary, as it cannot be assumed that the same orchid species has the same fungus at different locations. A broadly compatible fungus may be of considerable utility in conservation work, such as in situations where a specific fungus appears to have poor saprophytic competence or where soil conditions have been altered. Seed baiting studies provide additional data on fungal distribution in situ. In general, molecular data do not provide information about efficacy or fungal distribution, so research programs that combine symbiotic germination studies with seed baiting investigations and genetic analyses of the fungi will provide the maximum benefit for designing more effective conservation programs.
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42

佟穗海 and Shui-hoi Tung. "An ultrastructural study of megasporogenesis in oryza sativa, cymbidium sinense and phaius tankervilliae." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1997. http://hub.hku.hk/bib/B31214678.

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43

陳文頌 and Man-chung Chan. "Genetic diversity and relationships of spiranthes sinensis, S. spiralis, and S. hongkongensis (orchidaceae) as revealed by RAPD andcpDNA markers." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1997. http://hub.hku.hk/bib/B31214952.

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Tung, Shui-hoi. "An ultrastructural study of megasporogenesis in oryza sativa, cymbidium sinense and phaius tankervilliae /." Hong Kong : University of Hong Kong, 1997. http://sunzi.lib.hku.hk/hkuto/record.jsp?B18812090.

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45

Carroll, Audra L. "Sense and antisense oligonucleotide inhibition of the Odontoglossum ringspot virus (ORSV) coat protein gene via microprojectile bombardment of orchid callus tissue." Virtual Press, 1999. http://liblink.bsu.edu/uhtbin/catkey/1210536.

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A major goal of our laboratory is to confer resistence specifically to the Odontoglossum ringspot virus [ORSV; sometimes referred to as tobacco mosaic virus strain O (TMV-O)] in orchids. The chosen strategy may also provide cross-protection to other pathogens. The experimental design for the entire project is presented here along with the results obtained in several preliminary experiments performed in this research. Our approach involved RT-PCR amplification of the viral coat protein gene with gene-specific primers and digestion of the cDNAs into oligonucleotides. These fragments were cloned into the selectable vector pG35barB (which confers herbicide resistence) in both sense and antisense orientations. The cloned DNA was coated with tungsten beads and shot into orchid callus tissue using a makeshift biolistic gun. Tranformant callus cells were selected for by herbicide resistance. Unfortunately the potential transformants became contaminated with fungus and could nto be analyzed to determine which oligonucleotide was received and the effect each oligonucleotide had on pathogen resistance. Due to the uncertainty of the relatedness between ORSV and TMV-O, we also sequenced the coat protein gene of TMV-O and compared the amino acid sequence with those of several strains of ORSV: the Japanese strain had the highest percent amino acid similarity (99.4%), the Type strain the second highest (98.7%), and the Korean strain the lowest (96.9%). It was concluded that TMV-O is most likely one strain of ORSV, the Japanese strain.
Department of Biology
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46

Zu, Pengjuan. "Effects of Nectar Production and Pollinator Assemblies on Mating Patterns in Orchids." Thesis, Uppsala universitet, Växtekologi och evolution, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-159358.

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Pollinator visitation patterns should affect pollination success and mating patterns in flowering species. In the orchid family, about one third of the species do not provide any reward for their pollinators. Pollination by deceit is typically associated with low fruit set but may increase the chance of cross-pollination since the pollinator should soon leave the individual plant when there is no reward in the flowers. This may be beneficial if self-fertilisation results in inbreeding depression. I studied the mating patterns of one rewarding and one deceptive orchid in two closely related genera by tracking the fate of stained pollinia. I also conducted controlled crosses to estimate inbreeding depression. The results show that the deceptive orchid Dactylorhiza lapponica has lower pollination success, but higher cross-pollination rate (ca. 90%) than the nectariferous orchid Gymnadenia conopsea (ca. 18% cross-pollination). The results further suggest that in G. conopsea, nocturnal visitors mediate higher geitonogamous pollination rate (ca. 100%) than diurnal visitors (ca. 60%). In both study species, fruits produced from cross-pollination were heavier than fruits produced from selfing. Inbreeding depression for fruit mass did not differ significantly between the two species (δ = 0.21 in D. lapponica and δ = 0.29 in G. conopsea). These data support the hypothesis that pollination by deceit can enhance cross-pollination. A literature study including several rewarding and non-rewarding orchid species indicated lower geitonogamy in the deceptive orchids, but the difference was not statistically significant.
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47

White, David C. J. "Maintaining deception in a rewarding landscape; the pollination biology of deceptive orchids." Thesis, University of East Anglia, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.527630.

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48

Sanborn, Kristi L. "Phylogenetic analysis and identification of vanilla orchids : evidence from PCR sequencing/fingerprinting." Virtual Press, 1994. http://liblink.bsu.edu/uhtbin/catkey/897506.

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This research was an attempt to identify and provide a phylogeny of Vanilla orchids using PCR sequencing/ fingerprinting.Traditional classification methods haved relied heavily on morphological traits and are often contradictory, subjective and incomplete. This research attempted to discover an objective and reliable method for identification and classification of selected tropical orchids species using molecular techniques. Vanilla orchids were chosen for their commercial importance in the scent and flavoring industry.Reconstruction of phylogenetic data is possible using relatively new molecular techniques: Polymerase Chain Reaction (PCR) fingerprinting and sequencing. PCR fingerprinting reveals restriction fragment length polymorphisms (RFLPs) within an organism's genome. Thesevariations can be used to construct genetic maps in a variety of species. PCR sequencing reveals genetic variation at an even greater level: nucleotide sequence.The literature suggests that these methods are fairly quick and simple; however, the crucial step is obtaining high molecular weight DNA digestable with restriction enzymes or amplifiable by the PCR. DNA isolation has proven to be difficult with Vanilla orchids due to their numerous phenolic compounds, tough fibrous tissue and high number of polysaccharides. This research developed a method of isolating high molecular weight DNA from orchids. This DNA was digestible with restriction enzymes. The DNA was subjected to DNA fingerprinting with primers specific to the 18S-26S ribosomal RNA gene and with RAPD primers. The DNA was also sequenced using the PCR technique.Variation between Vanilla species genomes was discovered and compared to traditional phylogenetic information. It was found that banding patterns and nucleotide sequences were almost identical for Vanilla planifolia and planifolia varegata. The banding patterns for Vanilla barbellata were similar to those of the two unknown Vanilla orchids. Vanilla humboltii exhibited a banding pattern far different from either barbellata or planifolia. These results confirm the hypothesis that PCR fingerprinting/ sequencing is a useful technique for the identification and phylogenetic analyses of Vanilla orchids.
Department of Biology
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Huda, Mohammed Kamrul. "Diversity, ecology, reproductive biology and conservation of orchids of south east Bangladesh." Thesis, University of Aberdeen, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.327403.

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50

Alghamdi, Sameera. "Resolving the physiological ecology of symbiotic germination of epiphytic and terrestrial orchids." Thesis, University of Sheffield, 2015. http://etheses.whiterose.ac.uk/10507/.

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In the early life-stages, both epiphytic and terrestrial orchid seeds obtain carbon and nitrogen from mycorrhizal fungi for germination and seedling development. Epiphytic orchids are exposed to comparatively high light levels from an early stage of development and often produce green seeds therefore their responses to light and requirements for mycorrhiza-supplied C is likely to be different from terrestrial orchids. The effect of exogenous C, light and fungal partner on germination and establishment were studied in vitro for three terrestrial orchid and one epiphyte orchid. I found that terrestrial orchids require their fungal partner for development and that light inhibits this process. In epiphytic species, light only inhibited germination and early development in the absence of the mycorrhizal symbiont. The findings in this study shows for the first time the potential ecological importance of mycorrhizal fungi in overcoming light inhibition of seed germination and growth in both terrestrial and epiphytic orchid. I also investigate the impact of light, C and N budgets of terrestrial and epiphytes (using 13C and 15N tracers) and the amount of C and N the plant obtains from fungus to the adult orchid plants. The biomass and transfer of C and N from fungus to plant was increased upon exposure to light but only after germination had been already begun. The most cost benefit of mycorrhizal symbioses was examined as other studies have ignored C flow from plant to fungus. All three species gave C back to the fungus but in different quantities. Encyclia phoenicea provided significantly more C to its mycorrhizal fungi; twice the amount of G. repens and 2.4 times greater than D. fuchsii by mass. This confirms the mutualistic nature of G. repens-mycorrhiza interactions and reveals that this same trophic strategy operates in two additional orchid species for the first time.
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