Dissertations / Theses on the topic 'Shoot regeneration'
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Kanakis, Andreas G. "In vitro plant regeneration studies with Capsicum annuum." Thesis, University of Bath, 1987. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.380371.
Full textBoul, H. Lawrence. "A study of shoot regeneration in leaf disc cultures of two solanaceous plants." Thesis, University of Canterbury. Botany, 1992. http://hdl.handle.net/10092/5678.
Full textBarretto, Sherwin Savio. "Tobacco shoot regeneration from calli in temporary immersion culture for biosynthesis of heterologous biopharmaceuticals." Thesis, Imperial College London, 2014. http://hdl.handle.net/10044/1/44957.
Full textCraig, Jared Matthew. "EFFECTS OF MIDSTORY REMOVAL AND SHOOT CLIPPING ON THE GROWTH AND DEVELOPMENT OF THREE OAK SPECIES." UKnowledge, 2012. http://uknowledge.uky.edu/forestry_etds/9.
Full textBaloglu, Cengiz Mehmet. "Optimization Of Regeneration And Agrobacterium Mediated Transformation Of Sugar Beet (beta Vulgaris L.)." Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/3/12606476/index.pdf.
Full textKocer, Zeynep Ahsen. "In Vitro Induction Of Growth And Development Of Common Juniper (juniperus Communis L.) From Shoot And Bud Explants." Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/3/12605891/index.pdf.
Full textcallus induction, organogenesis, improved organogenesis and root induction experiments were performed sequentially. It was found that explant position, genotype, gender, treatments and sampling time had significant effects on callus induction rate in common juniper. The results of treatments indicated that IBA (indole-3-butyric acid) at concentration range 0.5-4.0 mg/l combined with MS medium supplemented with 0.1 mg/l BAP (benzylaminopurine), 3 % sucrose and 0.7% agar was the best one among the treatments to induce callus formation from common juniper explants collected as Spring buds. Also, a two-month culture was adequate period for the callus induction of common juniper regardless of position, before transferring the explants into organogenesis media. After a two-month culture in callus induction media, explants were transferred to organogenesis treatments in order to investigate adventitious bud development from callus tissues. There were significant differences among genotypes, treatments and explant-sampling times in initiation of organ development in common juniper. Additionally, it was found that excluding the auxin components while maintaining 1.0-2.0 mg/l BAP concentration in culture media, as refreshing after a month, stimulated the formation and development of adventitious buds and shoots. Among the treatments tested, it was found that 1.0 mg/l BAP plus 0.5 mg/l 2,4-D was the optimum culture media with adventitious bud formation capacity of 37.5% was though ageing of callus significantly affected the frequency of adventitious bud formation. Finally, rooting experiments were performed to investigate rooting efficiency of adventitious shoots. In the adventitious rooting experiments, no rooting was observed in any of the treatments used with common juniper explants. Although whole plantlet development from callus tissues could not be achieved as indirect organogenesis, the results of the study could aid to future studies dealing in vitro regeneration and production of secondary chemicals from common juniper.
Notini, Marcela Morato. "Understanding hormonal and temporal factors associated with tomato (Solanum lycopersicum L. cv. Micro-Tom) acquisition of competence: key concepts for in vitro shoot regeneration." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/11/11144/tde-07032018-132615/.
Full textA regeneração de plantas através da organogênese de novo é uma fase crítica para a maioria dos procedimentos de micropropagação e transformação genética. Recentemente, progressos significativos tem sido alcançados no entendimento dos mecanismos fundamentais à organogênese de novo de tomateiro (Solanum lycopersicum). Entretanto, fatores hormonais e moleculares envolvidos na aquisição de competência para formação de gemas caulinares na espécie, etapa essencial ao processo de regeneração, permancece desconhecido. O fracasso em adquirir competência pode ser associado a amplamente descrita incapacidade de tomateiro em regenerar brotos caulinares a partir de raízes. No primeiro capítulo, realizou-se uma caracterização temporal e hormonal das fases de aquisição de competência e indução de gemas caulinares usando a cultivar modelo Micro-Tom. A eficiência de regeneração foi melhorada através de pré-incubação em meio indutor de raízes (RIM) durante os dois primeiros dias de cultivo, período correspondente à fase de aquisição de competência em explantes cotiledonares. Diferentemente, a pré-incubação em outro meio rico em auxina, o meio indutor de calo (CIM), sob mesmo intervalo, aboliu completamente a regeneração. A pré-incubação de dois dias em RIM induziu uma intensa e extensa resposta a auxina endógena no explante, o que provavelmente aumentou a competência das células a induzir brotos caulinares em resposta a citocinina presente no meio indutor de gemas caulinares (SIM). A aplicação desse conhecimento na melhoria do procedimento de transformação genética via Agrobacteria levou a um eficiente, simples, barato e genótipo-independente protocolo. No segundo capítulo, nós desenvolvemos um método inédito de regeneração de tomateiro via explante radicular. A formação de brotos caulinares foi obtida por ajuste do pré-tratamento em CIM ao período de aquisição de competência, correspondente a quatro dias de cultivo em explantes radiculares. O número e qualidade dos brotos também foram elevados pela otimização do explante, composição do meio de cultivo, e condições de cultivo. Somando-se os dois capítulos, o conhecimento obtido a cerca da competência organogênica resultou em novos sistemas de regeneração e transformação genética, ferramentas importantes para processos biotecnológicos e estudos funcionais de genes específicos em tomateiro.
Aissa, Abdi Fatima. "Mitochondrial complex I dysfunction enhances in vitro plant organogenesis." Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLS136/document.
Full textIn vitro shoot regeneration is a complex process routinely used for vegetative propagation and to study plant organogenesis. Despite multiple applications of in vitro shoot initiation, the regulatory mechanisms involved remain poorly understood. Prior to the beginning of my PhD thesis, we identified an Arabidopsis thaliana mutant in which a defect in the complex I of the mitochondrial electron transport chain (mETC) results in a higher shoot regeneration rate compared to wild type, measured on protoplast-derived calli. At the beginning of my PhD project, I confirmed the link between the respiratory defect and the shoot regeneration boost with a specific complex I inhibitor called rotenone. To understand this phenomenon, I investigated the molecular and biochemical mechanisms linking mitochondrial respiration and shoot organogenesis. For this purpose, I analyzed different mutants affected in the complex I activity and concluded that the resulting growth retardation is positively correlated with the regeneration rate. To understand how mETC perturbations promote shoot regeneration, I compared gene expression profiles in complex I mutant tissues and in calli treated with rotenone. Our data show, on the one hand, that gene expression profiles are different in complex I mutants and, on the other hand, that rotenone induces an oxidative stress, inhibits cell proliferation, and modulate hormonal regulations. I confirmed that the oxidative response induced by rotenone is rapidly relayed in the cytosol with a redox- sensitive biosensor. Altogether, our results suggest a causal link between an oxidative stress caused by respiratory impairments and shoot regeneration enhancement. Our findings point to alternative methods to promote in vitro organogenesis via transient inhibition of mitochondrial activities
Rocha, Gabriel Henrique Braga. "Análise do papel da via miR156/SQUAMOSA Promoter-Binding Protein-Like (SPL) na organogênese in vitro a partir de raízes de Arabidopsis thaliana." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/11/11144/tde-17062016-180648/.
Full textMicroRNAs (miRNAs) are endogenous small non-coding RNAs of 21-24 nucleotides (nt) in length that regulate target gene expression. They are involved in many aspects of plant development, both in the shoot and in the root systems. Among miRNAs, miRNA156 (miR156) regulates SQUAMOSA Promoter Binding-Like (SPL) transcription factor family affecting different plant development processes. Recent studies have shown that the miR156/SPL pathway has a positive effect both in the increase of lateral root formation and regeneration of shoots from leaves and hypocotyls in Arabidopsis thaliana. Because the origin of lateral root formation and in vitro shoot regeneration from primary root share similar anatomical and molecular features, in the present study was evaluated whether the miR156/SPL pathway, in the same manner that from aerial explants, is also able to influence the in vitro shoot regeneration from root explants. For this, it was compared regeneration rates, distribution pattern of auxin and cytokinin, histological and histochemical analyses of the structures regenerated in plants in with the miR156/SPL pathway is modified, including the mutant hyl1-1, in which the biosynthesis of this miRNA is severely reduced. Besides that, it was evaluated the expression pattern of miR156 and specific SPL target genes during in vitro shoot regeneration from primary roots of Arabidopsis it was observed that the alteration on the miR156/SPL pathway is capable to modulate in vitro shoot regeneration from the primary root of Arabidopsis and the distribution of auxin and cytokinin at the tissues and cells involved in the regeneration process. Plants overexpressing the miR156a have shown reduction in the number of regenerated shoots, and displayed a reduction in plastochron when compared with wild type plants. Additionally, plants expressing cleavage-resistant form of SPL9 (rSPL9) presented severe reduction in the amount of shoots, and extended plastochron. Interestingly, mutant hyl1-2 and plants rSPL10 did not show any shoot regeneration along the root, but high formation of lateral roots and protuberances, respectively, having rSPL10 presented evidence of precocious cell differentiation. Taken together, these data suggest that de miR156 and SPLs have an important role in the control the in vitro shoot regeneration process. However, its effect is somehow more complex in roots than in cotyledons or hypocotyls.
Raikar, Sanjeev Vencu. "Protoplast fusion of Lolium perenne and Lotus corniculatus for gene introgression." Phd thesis, Lincoln University. Bio-Protection and Ecology Division, 2007. http://theses.lincoln.ac.nz/public/adt-NZLIU20080214.105406/.
Full textFernando, Kumudu. "Gene expression during regeneration of shoots in tobacco by tissue culture." Thesis, University of Bath, 1992. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.305058.
Full textSafdar, M. Taifoor, Khawar Hanif, and Shakeel Ahmad Ghumman. "Super-Regenerative Receiver (SRR) for short-range HF band applications." Thesis, Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-2448.
Full textThis master thesis describes a radio reciever with simple architecture which operates at 20 MHz. This is based on low-cost amplifier design. Super-Regenerative Receiver (SRR)is re-examined for its simplicity, low-power and short-range wireless applications. Power consumption is kept to a minimal level without any change in the performance of reciever by providing minimum biasing to discrete devices. This report shows how with the help of modern computer based investigation and simulation tools, a much more wide-ranging characterization of the behavior of the reciever is possible.
The Simulation software used to implement this model i advanced Designed System, ADS2006A. This designed model consist of two stages,the linear pre-amplifier stage and the super-regenerative oscillator (non-linear stage). The linear stage has a 1th-order low band-pass filter which connects the input terminal end with the pre-amplifier, while the non-linear stage is consist of class with LC resonant tank, and the self-quenching circuit.
The fundamental quench frequency of this reciever is 8 kHz. In the simulation, the supplied voltage, VDD, is 5,0 volts is used which produced input current of 5,06 mA. The results show that the designed model presents its best performance at the 20 MHz radio frequency (RF).
Safdar, M. Taifoor, Khawar Hanif, and Shakeel Ahmad Ghumman. "Super-Regenerative Receiver (SRR) for short-range HF band applications." Thesis, Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-4209.
Full textThis master thesis describes a radio receiver with architecture which operates at 20 MHz.This is based on low-amplifier design. Super-Regenerative Receiver (SRR) is re-examined for its simplicity, low-power, and short-range wireless applications. Power consumption is kept toa minimal level any change in the performance of receiver by providing minimum biasing to discrete devices. This report shows how with the help of modern computer based investigation and simulation tools, a much more wide-ranging characterization of the behavior of the reciever is possible.
The simulation software used to implement this model is advanced Designed System, ADS2006A. This designed medel consists of two stages, the linear pre-amplifier stage and the super-regenerative oscillator (non-linear-stage). The linear stage has a 1st-order low band-pass filter which connects the input terminal end with the pre-amplifier, while the non-linear stage is consists of class C amplifier with LC resonant tank, and the self-quenching circuit.
The fundamental quench frequency of this reciever is 8 kHz. In the simulation, the supplied voltage, Vdd, is 5.0 volts is used which produced input current of 5.06 mA. The result show that the designed model presents its best performance at he 20 MHz radio frequency (RF).
Cohen, Susan Alese. "Regenerating Longleaf Pine on Hydric Soils - Short-Term Effects on Soil Properties and Seedling Establishment." NCSU, 2008. http://www.lib.ncsu.edu/theses/available/etd-04282008-191226/.
Full textGrishin, Mikhail. "Dynamics of continuously pumped regenerative laser amplifiers." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2011. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2011~D_20110628_134556-72562.
Full textŠioje disertacijoje tiriami nuolatinai kaupinami regeneraciniai stiprintuvai su ilgos relaksacijos trukmės lazerine terpe. Tikslas buvo išanalizuoti bendrus tokių sistemų sudėtingos dinamikos dėsningumus pasireiškiančios aukštų dažnių diapazone ir surasti būdą pasiekti maksimalias išėjimo impulsų energijas išlaikant jų stabilumą. Analitiškai aprašomos pagrindinės optimizuotų ir stabiliame režime veikiančių stiprintuvų charakteristikos, tokios kaip optimalūs pradinis ir galutinis stiprinimo koeficientai, maksimali išėjimo impulso energija, rezonatoriuje išsklaidytoji galia, daugelio praėjimų B-integralas ir rezonatoriaus apėjimų skaičius, su kuriuo gaunama maksimali išėjimo impulso energija. Nustatytos egzistuojančių dinaminių režimų (stabilaus, kvaziperiodinio ir chaotinio) sritys valdančiųjų parametrų erdvėje. Išsiaiškinta, kad nestabilaus veikimo sritis mažėja, kai užkrato impulso energija didėja. Sukurtas ir išplėtotas stabilumo diagramų metodas, kuris ne tik suformuoja sisteminį požiūrį į regeneracinio stiprinimo dinamikos optimizavimą, bet ir leidžia nustatyti užkrato energijos dydį, pakankamą stabiliam veikimui palaikyti. Nustatytos darbinės charakteristikos kritiniame impulsų pasikartojimo dažnių diapazone, kur neegzistuoja analitiniai sprendiniai ir nestabilumai yra labiausiai tikėtini. Teoriniai rezultatai patvirtinti eksperimentiškai diodais kaupinamoje pikosekundinėje Nd:YVO4 lazerinėje sistemoje. Pademonstruota, kad užkrato impulso energijos padidinimas susiaurina... [toliau žr. visą tekstą]
Gonçalves, Micael Ferreira Mota. "Development of novel short and long term studies in Enchytraeus crypticus." Master's thesis, Universidade de Aveiro, 2016. http://hdl.handle.net/10773/18562.
Full textA maioria dos estudos ecotoxicológicos têm investigado os efeitos de curto prazo dos contaminantes. Comparativamente, tem sido desenvolvido pouco trabalho na avaliação dos efeitos a longo prazo dos químicos existindo portanto uma necessidade de preencher esta lacuna. De entre as espécies de solo usadas em ecotoxicologia estão os Enquitraídeos (Oligochaeta), membros importantes da mesofauna terrestre com diretrizes padrão para testar os efeitos ao nível da sobrevivência, reprodução e bioacumulação (ISO, 2004; OECD, 2010, 2004). Para a espécie Enchytraeus crypticus, existe também disponível o cDNA microarray com mais de 40 000 transcritos (Castro-Ferreira et al., 2014) sendo uma vantagem competitiva em relação a outras espécies padrão. O principal objetivo desta pesquisa foi desenvolver novos testes de curto e longo prazo, abrangendo novos/diferentes endpoints para E. crypticus. A habilidade de regeneração do E. crypticus foi descoberta e o processo de regeneração foi descrito; este pode ser adicionalmente utilizado para avaliar os efeitos de tóxicos em testes de curto prazo. O desenvolvimento embrionário de E. crypticus foi investigado e um teste de embriotoxicidade foi desenvolvido (pela primeira vez em um invertebrados do solo). O cádmio (Cd) foi usado como substância de teste para validar o teste embriotoxicidade dados os seus conhecidos efeitos embriotóxicos. Os resultados mostraram que o Cd causou uma diminuição no sucesso da eclosão devido a um atraso ou interrupção na formação de estruturas embrionárias. Um teste de longevidade (com avaliação da sobrevivência e reprodução ao longo do tempo) foi desenvolvido para E. crypticus. Este ensaio de exposição de longo prazo foi utilizado para avaliar os efeitos de nanopartículas de óxido de cobre (CuO-NPs) em comparação com CuCl2 revelando que CuO-NPs causou efeitos superiores (diminuindo a longevidade e reduzindo a reprodução) do que CuCl2, a uma concentração de efeito semelhante. Este ensaio traz um novo conceito em ecotoxicidade, a longevidade. Este é um especto particularmente importante quando o assunto é a toxicidade de nanomateriais (NMs), onde se espera que o tempo de exposição a longo prazo revele efeitos imprevisíveis através dos testes correntes de curto/longo prazo. O uso dos novos ensaios desenvolvidos podem melhorar a avaliação dos perigos dos produtos químicos.
Most of the ecotoxicity studies have investigated the short-term effects of chemicals. Comparatively, little work has been done in the assessment of the long-term effects of chemicals and there is a need to fill this gap. Among soil species used in ecotoxicology are Enchytraeids (Oligochaeta), important members of the terrestrial mesofauna with standard guidelines for testing effects at survival, reproduction and bioaccumulation level (ISO, 2004; OECD, 2010, 2004). For the species Enchytraeus crypticus, there is also available the cDNA microarray with more than 40 000 transcripts (Castro-Ferreira et al., 2014) being a competitive advantage in comparison to other standard species. The main goal of this research was to develop novel short and long-term tests, covering new/different endpoints, for E. crypticus. Regeneration ability of E. crypticus was discovered and the regeneration process was described; this can be further used as endpoint to assess the effects of toxicants in short-term studies. The embryonic development of E. crypticus was investigated and an embryotoxicity test was developed (for the first time in a soil invertebrate). Cadmium (Cd) was used as a test substance to validate the embryotoxicity test given its known embryotoxic effects. Results showed that Cd caused a decrease in the hatching success due to a delay or disruption in formation of embryonic structures. A lifespan test (with assessment of survival and reproduction over time) was developed for E. crypticus. This long-term exposure assay was used to assess the effects of copper oxide nanoparticles (CuO-NPs) in comparison with CuCl2 revealing that CuO-NPs caused higher effects (shortening lifespan and reducing reproduction) than CuCl2, at similar effect concentration. This lifespan assay brings a novel concept in ecotoxicity, the longevity. This is a particularly important aspect when the subject is nanomaterials (NMs) toxicity, where longer term exposure time is expected to reveal unpredicted effects via the current short/long-term tests. The use of the new assays developed can improve the hazard assessment of chemicals.
Raikar, S. V. "Protoplast fusion of Lolium perenne and Lotus corniculatus for gene introgression." Diss., Lincoln University, 2007. http://hdl.handle.net/10182/301.
Full textGeorgitis, Kathryn M. "Evaluating Shade Bias in Insect Trap Catch and Assessing the Short- and Long-term Impacts of Herbicide Application in Regenerating Clearcuts on Flowering Plant Communities." Fogler Library, University of Maine, 2001. http://www.library.umaine.edu/theses/pdf/GeorgitisKM2001.pdf.
Full textPan, Gong. "FenFlux : the short term climate response of carbon dioxide and methane fluxes from a regenerating and a semi-natural fen in East Anglia, United Kingdom." Thesis, University of Leicester, 2017. http://hdl.handle.net/2381/39874.
Full textSánchez-Duran, José Antonio. "Neural plasticity in premotor pathways of the Aplysia feeding system : short-term synaptic modulation of motor programs, synaptic interactions, regeneration of cerebral-buccal connections, and recovery of buccal motor programs /." free to MU campus, to others for purchase, 2001. http://wwwlib.umi.com/cr/mo/fullcit?p3013019.
Full textGolinelli, Anna. "Development of an original 10 kHz Ti : Sa regenerative cavity allowing 17 fs CEP stable 1 kHz TW-class amplification or wavelength tunability." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS018.
Full textThe last decade has seen a lot of progress in attosecond science or in strong field physics. Generating energetic, few-cycle laser pulses with stabilized Carrier-Envelope Phase at high repetition rate constitutes the first step to access the ultra-fast dynamics underlying the interaction of matter with intense, ultrashort coherent light source. The work of this thesis consists in globally improving the performances of a high repetition rate Ti:Sa laser system optimized for attosecond science. We present an original 10 kHz Ti:Sa CPA laser based on an newlydesigneddouble-crystal cavity for thermal lensing management. The amplifier delivers up to 5 W in narrow band mode (35 fs pulses), or 2.7 W in broad band mode, supporting 17 fs pulses after temporal compression. We demonstrate shot-to-shot CEP stabilization with a remaining noise of 210 mrad over three hours at the front-end output. In parallel to the short pulse duration operation mode, it is possible to use the front end in a wavelength tunability mode within a 80 nm range around 800 nm, with a resolution of 1 nm and 30 to 40 nm of bandwidth. We designed and demonstrated a complete water-cooled lens-less multipass amplifier using thermal lensing for modeadaptation boosting the pulse energy up to 10mJ at 1 kHz repetition rate (up to 10 W). The saturation regime of the amplifier ensures negligible variation (±3% peak to peak) of the output power for significant variation of the input power (±25% peak to peak) over the tunability range. The energy scalability of the front-end is demonstrated by coupling its output to cryogenically cooled amplifier, delivering 1 kHz, TW-class pulses at 17.5 fs and CEP stabilized with a residual noise of 350 mrad. A study of CEP noise sources in high dispersive module is also addressed, proposing a numerical approach based on a commercial ray-tracing software (Zemax) for predicting CEP fluctuation in grating based modules
Grishin, Mikhail. "Nuolatinai kaupinamų regeneracinių lazerinių stiprintuvų dinamika." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2011. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2011~D_20110628_134544-62447.
Full textThis thesis presents a detailed study of continuously pumped regenerative amplifiers based on long-relaxation-time laser media. The goal of the research was to develop a general pattern of complex dynamics peculiar to such systems at high repetition rates and to find a way to improve performance characteristics affected by instabilities. Basic parameters of the optimally coupled regenerative amplifier operating in stable regime were derived in analytical form. They include optimum initial and final gains, the maximum output pulse energy, the power dissipation, the multi-pass B-integral and the roundtrip number providing the maximum output energy. A comprehensive pattern of existing dynamic regimes (stable, quasi-periodic and chaotic) was represented in space of controlling parameters. It has been found that the space of unstable operation decreases as the seed pulse energy increases. A method of stability diagrams, which forms a systematic approach to the optimization of regenerative amplification dynamics and in particular allows one to determine the seed pulse level sufficient to maintain the operation stable, has been developed. Performance characteristics were determined in the critical range of repetition rates, where instabilities are pronounced at the most and analytical solutions are unavailable. The experiments, carried out using the diode pumped picosecond Nd:YVO4 laser system, exhibited a good agreement with theoretical inferences. It has been demonstrated that... [to full text]
Oliveira, Leandro Silva de. "Propagação de Eucalyptus cloeziana F. Muell." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/11/11150/tde-05052014-154718/.
Full textEucalyptus cloeziana has importance for its wood technologic characteristics, mainly the durability, density and resistance. Moreover, this species has limitations on adventitious rooting of cuttings, having difficulties to obtain clonal seedlings and to advance in the improvement programs. In this perspective, the present work aimed to evaluate the E. cloeziana micropropagation by juvenile and mature explants as a technique for propagation this specie. Therefore, the work was divided into four basic studies. The first study was the establishment of the protocol to indirect organogenesis to E. cloeziana hypocotyls and cotyledons. In the second study evaluated the rescue of E. cloeziana adult matrices for epicormic shoots induction in crow branches. In the third study was definite a micropropagation protocol by axillary branching of E. cloeziana adult matrices. Finally, in the fourth study was evaluated the in vitro rejuvenation of E. cloeziana adult matrices to micropropagation by axillary branching and the micro-cutting technique of in vitro rejuvenated matrices to prove the in vitro culture viability to the propagation of this specie. The indirect organogenesis E. cloeziana was dependent of explant type and growth regulator and its concentration used in the different morphogenesis phases. The adventitious shoots were multiplicities and acclimatized with success to obtain E. cloeziana clonal seedlings. The vegetative rescue results of E. cloeziana adult matrices showed a higher induction epicormic shoots from branches collected in warmer and rain season. The medium diameter between 2.0 and 5.0 cm was considered the better to obtain higher epicormic shoots number in vegetative rescue. The micropropagation protocol of E. cloeziana adult matrices was realized with success using epicormic shoots, induced in the branches, like explants. The shoots in vitro multiplication was realized on WPM medium culture, supplemented with BA and NAA. The better growth regulators concentrations were different for each genotype. Treatments pulse with GA3 was not suitable to promote the elongation of shoots in vitro, which was obtained by the BA concentration reduction at 0.1 mg L-1. The in vitro shoots acclimatization and ex vitro rooting was performed in mini-incubators with success and it permit to obtain clonal seedlings from E. cloeziana adult matrices to form a clonal micro-garden. The shoots of E. cloeziana adult matrices showed different in vitro multiplication rates with specific-genotype responses to micropropagation. The micro-cutting technique results of E. cloeziana adult matrices provide evidence that occurred in vitro rejuvenation of these genotypes, during the micropropagation. Therefore, the nursery results showed that other factors, not only maturation, can be involved in the adventitious recalcitrance of E. cloeziana. In conclusion, the importance micropropagation like a biotechnological tool to propagation of E. cloeziana was proved and opened important perspectives for future investigations to optimize the propagation methods for this specie.
Sung, Lun-Chang, and 宋倫彰. "Adventitious shoot regeneration of eggplant interspecific hybrid." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/31162282829533295934.
Full text國立屏東科技大學
農園生產系所
101
Eggplant (Solanum melongena L.) is a vegetable and medicinal plant good for human health; furthermore, eggplant is an important crop all over the world. A number of studies report the regeneration of large number eggplants through tissue culture; for example, researchers would add hormone in the tissue culture media to induce the plant regeneration. Many reports were also indicated that using different explants of eggplant such as the leaves, roots, cotyledons, hypocotyls, and nodes, to induce plant regeneration. However, the studies which induce regeneration of eggplant interspecific hybridization varieties with various light intensity condition were limited. Consequently, in our experiment will use leaf explants of eggplant treating with artificial hormones, such as Auxin (naphthaleneacetic acid, NAA), Cytokinin (6-benzyladenine, BA) and Thidiazuron (TDZ) and with different light intensity conditions to induce plant regeneration. In the study, the effect of leaf explants treated with NAA and BA to induce shoot regeneration eggplant interspecific hybridization varieties were not significantly. On the other hands, IV TDZ have higher efficiency shoot regeneration rates than NAA and BA. The in vitro shoot were obtained in MS medium supplemented with 0.1 mg/L TDZ, having an average shoot number of 4.94 ± 1.84 per leaf explants (not fix size) in normal light intensity (35μmol/m2/s) for 21 days; on the other hand, the leaf explants (5 mm2) cultured in MS medium supplemented with 0.1 mg/L or 0.25 mg/L TDZ which in vitro shoot number was more leaf explants than that none fixed size, having average 11.19 ± 2.54 and 12.30 ± 3.30 per explants, respectively. The best in vitro shoot induction was achieved on MS medium supplemented with 0.1 mg/L TDZ, with an average of 15.41±0.71 per leaf explants (0.5mm2) in low light intensity (13 mol/m2/s). In our experiment, histology analyzing indicated that the in vitro shoot was through the organogenesis adventitious shoot. Finally, the adventitious bud inducing from the leaf explants treated with 0.1 mg/L TDZ in low light intensity would be growing and development after subculture to MS medium with hormone free in the normal light intensity condition for 42days. Furthermore, the upper leaf explants have highest survival rates after subculture to the MS medium for 42 days. On the other hand, the adventitious shoot inducing from the leaf explants all of position wouldn’t be growing and development after subculture to the MS medium without any plant growth regulator for 42 days; moreover, that have lowest survival rate. We were fined the optimal light intensity and concentration of artificial hormones, TDZ, to induce leaf explants of eggplant regeneration. The future we can try to use TDZ to induce regeneration of other eggplant interspecific hybridization varieties in the future.
Su, Wei-Ting, and 蘇暐婷. "Somatic embryogenesis and shoot regeneration of Salix garcilistyla Miq." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/77869279153910774459.
Full text國立宜蘭大學
園藝學系碩士班
98
Salix garcilistyla Miq. is perennial deciduous shrub of Saliaceae. It is important for flower of crop in area of Sunshin of Ilan, like warm, humid and abundant sunshine of climate. This study establish complete regeneration system of Salix garcilistyla Miq. by tissue culture to probe into conditions and method of plant regeneration used different explants such as shoot apex, nodal segments and leaves, also used paraffin section technique to observe process of growth regulator to induce callus differentiation, somatic embryogenesis and shoot regeneration. This study are length less than 0.5 cm of shoot apex of Salix garcilistyla Miq. ‘Lanyang No. 1’ , bud are not growth and easy to browning when culture in add different concentration of TDZ of solid medium. In light condition, the length about 0.5-1 cm of shoot apex culture in filter paper bridge in liquid medium, the medium no add TDZ have better growth and without browning, and bud browning rate raise follow with TDZ concentration increase, highest of browning rate of bud in add 0.5 μM TDZ medium. Leaf explants separately culture in add 27 μM 2,4-D of liquid or solid of MS medium, the callus form rate in liquid medium is rapid than solid medium, but amount of callus are not different. Leaf explants are easier to brownng in light condition(45±5 μmol m-2 s-1)than dark condition(0 μmol m-2 s-1). That exhibit different luminosity Effects explant browning rate. Callus separately subculture in add different concentration of TDZ, BA, Kinetin and no add plant growth regulators of MS medium. The results are all of the highest amount of callus multiplication in no add plant growth regulators of MS medium. Callus at different concentrations of Cytokinins(TDZ、Kinetin、BA)medium will increase the amount of callus multiplication, but don’t induce shoot regeneration. Shoot regeneration in add 1μM NAA and 0.5μM kinetin of MS medium.
Shu, Ming-Chi, and 許銘志. "Adventitious shoot induction and plant regeneration of Begonia × hiemalis." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/46456165723731199206.
Full text國立嘉義大學
農學研究所
95
Adventitious shoots were successfully regenerated using leaf or petiole of explants from Rieger Begonia ( Begonia × hiemalis ‘Barkos’ ). Leaf or petiole sections were cultured on MS medium containing different concentration of NAA ( 0.1、1 mg/l ) and BA ( 0.1、0.5、1、5 mg/l ). The culture medium was optimized for the leaf or petiole explants derived from shoot which was supplemented on MS medium with 1 mg/l NAA and 0.5 mg/l BA and observed 8.5 or 12.6 shoots from each explant after eight weeks, respectively. Hundred percent shoot regeneration and 8.4 shoots per explant was obtained when leaf cutting position near the petiole position of leaf explants and it was significantly different from leaf cutting position near the middle and margin of explants. Histological studies showed that adventitious shoots originated from both leaf or petiole epidermis layer and then differentiate to the formation of apical meristems and leaf primordial structures and it did not show intact somatic embryogenesis. Histological observation revealed that regeneration of leaf or petiole explants via organogenesis. Further elongation of adventitious shoots was obtained from each explant on full strength MS solid medium or liquid- shake medium with average of 10.9 and 12.2 plantlets, respectively. However, shoot only a few plantlets was obtained shoot of petiole explants on full strength MS solid medium or liquid-shake medium. All the regenerated plantlets were 90 % survival rate and continued to grow after the transfer to plastic pots. No morphological aberrations were observed in the regenerated plants.
Liang, Wenqing. "Factors affecting shoot regeneration and genetic transformation of a self-compatible accession of Lycopersicon peruvianum /." 1994. https://scholarworks.umass.edu/theses/3446.
Full textChen, Yi-Rung, and 陳伊蓉. "Study on the Relationship Between Aldose Reductase and Shoot Regeneration in Rice Callus." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/00001220949412756538.
Full text國立嘉義大學
農藝學系研究所
99
It’s well known that osmotic stress can induce somatic embryogenesis and further shoot regeneration in rice callus. The mechanisms of totipotency are less understood so far even though plentiful research has been discussed with respect to cell differentiation. The purpose of this study was explored the possible role of Aldose Reductase gene (OsARs), which is subjected to ABA and stresses regulation, during callus induction and shoot regeneration in rice. The immature embryos from three genotypes of rice relevant to OsAR5, Tainung 67 (TNG67; OsAR5 wild-type), OsAR5 overexpression transgenic lines (OxAR5), and OsAR5 T-DNA insertion mutant (KoAR5) were used in present study. The callus were derived from N6D2 (N6 basal medium containing 2 mgL-1 2,4-D) induction medium supplemented with different concentration of sorbitol (0, 0.3M, 0.6M), represented as N6D2S0, N6D2S3, and N6D2S6, respectively. It showed the callus induction rate, fresh weight, and water content were decreased significantly accompany with sorbitol concentration in all genotypes. In KoAR5 has the highest browning rate than the others. Besides, the 14-days-old of callus were transferred to N6K4N2 (N6 basal medium containing 4 mgL-1 kinetin and 2 mgL-1 NAA) regeneration medium. The result showed that has no plantlets regenerated from TNG67 in N6D2S0 and N6D2S3 treatment. It can be increased to 13% in N6D2S6 treatment. Besides, the shoot regeneration frequency in N6D2S3 and N6D2S6 from OxAR5 enhanced to 13% and 26% respectively. In opposite, all three treatments in KoAR5 have no shoot regenerated. It suggested that the expression of OsAR5 is relevant to shoot regeneration in rice callus. The reverse transcriptase polymerase chain reaction (RT-PCR) analysis and immunohistochemical localization of OsARs were further determined. The result showed that five OsARs genes can be detected in rice callus especially OsAR1 and OsAR2. The expression, except of OsAR5 is up-regulated by osmotic stress in TNG67 and OxAR5, the others seem have no significant difference no matter of with / without sorbitol treatment. In addition, it cannot detect any expression of OsAR5 in KoAR5 either callus induction or regeneration stage. According to the immunohistochemical analysis, the OsARs can be observed in the epidermis, peripheral layer, and tracheary elements during callus induction and shoot regeneration. The regenerable callus from N6D2S6 in TNG67 has more obviously distribution of OsARs. The result is consistent with our previous study that shoot regeneration frequency is increased significantly by osmotic stress treatment in rice callus. We suggested that OsAR5 is closely related to shoot regeneration induced by high concentration of sorbitol treatment. It may have roles on detoxification of reactive aldehyde compounds and osmotic adjustment under osmotic stress treatment. This is the first study to mention the correlation between plant differentiation and AR. More morphological, physiological, and gene expression analysis is necessary to clarify the possible role of OsARs during shoot regeneration in rice callus under osmotic stress treatment.
詹守怡. "Studies on protocorm like body induction 、multiplication and shoot regeneration of Phalaenopsis hybrids." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/86901209715151173095.
Full text國立嘉義大學
農學研究所
91
The purpose of this research was to find the best media formula and cultural environment for PLB induction, PLB proliferation and shoot regeneration of Phalaenopsis hybrids. Using lateral buds removed from young flower stalks as explants, NDM(New Dogashima Medium)was the best medium formula for PLB induction in Phal. ‘Wedding promenade’ among the 1/2MS(Murashige and Skoog),VW(Vacin and Went) and Hyponex basal medium formula. The rate of PLB formation for lateral buds cultured on NDM medium containing NAA 0.1 mg/L and BA 1.0mg/L in Dtps. Nobby's Pink Lady ‘T699’ × Dtps. Taisuco Firebird ‘DL18’ and Dtps. Minho Princess was 34.6% and 26% respectively. However, The rate of PLB induction for lateral buds cultured on the NDM medium containing NAA 0.1 mg/L and BA 2.0mg/L in Phal. ‘Wedding promenade’ was 77﹪. Therefore, The effect of basal medium on PLB induction in Phalaenopsis showed lots of variations among the hybrids. Using short-stems removed from shoots in vitro, 1/2MS and Hyponex media were more available for PLB induction in Dtps. Minho Princess ‘MH903’ than NDM medium. Sucrose in the NDM medium was more productive for PLB induction than maltose and glucose in Dtps. I-Hsin Actor ‘KH5213’、Phal. Tinny White ‘TT1006’ and Phal. Taisuco Roseherz × Dtps. King Shiang’s Rose × Dtps. King Shiang’s Coral. The optimum carbonhydrate concentration in NDM medium for shoot and PLB formation ranged from 0.5%. PLBs as explants subcultured on 1/2MS, NDM and Hyponex medium formula in Phal. Taipei Gold ‘T. G.’ × Phal. Black Eagle ‘KH1872’ and Dtps. Sinica Ruby ‘KH5498’, not only PLB proliferation occurred, but also shoot regenerated. PLB subcultured on Hyponex medium containing NAA 0.1mg/L showed the highest rate of PLB proliferation in Phal. Taipei Gold ‘T. G.’ × Phal. Black Eagle ‘KH1872’. The highest number of regenerated shoots per explant appeared in the medium containing NAA 0.1mg/L and BA 2mg/L. However, PLB explants subcultured on Hyponex medium free of NAA and BA had the highest rate of PLB proliferation in Dtps. Sinica Ruby ‘KH5498’. It was found that Hyponex medium containing NAA 0.1mg/L and BA 4mg/L was best for shoot regeneration from PLB in Phal. Taipei Gold ‘T. G.’ × Phal. Black Eagle ‘KH1872’. Hyponex medium free of NAA and BA was more available not only PLB proliferation, but also for shoot regeneration in Phal. Taipei Gold ‘T. G.’ × Phal. Black Eagle ‘KH1872’ and Dtps. Sinica Ruby ‘KH5498’.
Huang, Wen-Lii, and 黃文理. "Studies on Carbohydrate Metabolism in Rice Callus During Shoot Regeneration Induced by Osmotic Stress." Thesis, 1998. http://ndltd.ncl.edu.tw/handle/96394595848390674549.
Full text國立臺灣大學
農藝學系研究所
86
This thesis was conducted to explore the possible mechanisms of shoot rege neration from rice callus induced by osmotic stress. The relationships among osmotic stress, endogenous phytohormone levels, carbohydrate metabolisms,and s hoot regeneration were studied. In addition, the "regeneration-related factor s" were discussed in this thesis. The calli were induced from immature embr yos of two rice cultivars (Oryza sativa L.) and used for regeneration experime nts. One is Ai-Nan-Tsao 39, ANT39, whose callus showed high shoot regeneratio n ability. The other is Tainan 5, TN5, whose callus showed greatly increased regeneration frequency only after being exposed to an osmotic stress exerted b y either metabolizable (ex. sucrose) or non-metabolizable (ex. mannitol) sacch arides. At first, the callus growth, shoot regeneration frequency, water and osmotic potentials of culture mediumand callus under different osmotic stress treatment were determined. Then, the cellular contents of soluble sugars and starch, and the cellular localization and activities of enzymes related to the ir metabolism, including Sol-IT, Bound-IT, SS, AGPase, SPase, α-Amy, and β-A my of rice calli and shoot regenerating tissues were systematically analyzed. Finally, changes of carbohydrate metabolism was further investigated in TN5-An A treatment, in whichosmotic stress was replaced by 2mM anthranilic acid and 1 00μM ABA. The results showed, highly regenerable callus, ANT39-Dry, TN5-Su c18, and TN5-M6, have lower callus growth rate, water content, cellular water and osmotic potentials than un-regenerable callus, TN5. It suggested that sho ot regeneration is closely related to cellular osmotic status. In addition, h igher starch and sucrose contents at callus induction stage and a sudden incre ase or retaining higher glucose content at the first day after the callus bein g transferred to regeneration medium were found in highly regenerable callus. The starch and sucrose contents were decreased during shoot regeneration. Th e phenomenon of starch accumulation and disappear were also observed from hist ochemical analysis. On the other hand, there are no significant changes in ca rbohydrate contents and histochemical appearance in un-regenerable callus. We concluded, therefore, the higher starch content at callus induction stage and higher glucose content at the initiation of shoot regeneration stage were bot h the important "regeneration-related factors" in rice callus. The carbohyd rate metabolic pathway was different between ANT39-Dry and TN5-M6 although the changes of carbohydrate contents were similar. In ANT39, the lower Bound-IT and SS, higher Sol-IT activity at callus induction stage suggested that sucros e might be uptaken by sucrose transporter mainly. In addition, both AGPase an d α-Amy are higher at this stage suggested that the higher starch content is the result of higher stasch biosynthetic ability. At the initiation of shoot regeneration stage, higher expression and enzyme activity of α-Amy, higher So l-IT, and lower Bound-IT and SS activity were found. These results might expl ain that the higher glucose content might come from degradation of both starch and sucrose. In contrast, it showed greatly increase of Sol-IT, Cound-IT, an d SS at callus induction stage in TN5-M6. It suggested that sucrose uptake fr om sucrolytic pathway dominantly. At the same time, TN5-M6 showed similar AGP ase but lower α-Amy activity than TN5. Thestarch accumulation, therefore, mi ght be caused by lower degradation of starch in TN5-M6. At the initiation of shoot regeneration stage in TN5-M6, higher Bound-IT and Sol-IT, lower amylase activity were found. It might suggest that higher glucose content is due to h igher sucrose uptake by Bound-IT mainly. Because starch content was also decr eased at the same time, it might have another starch degradation pathway, for example, SPase, which showed higher SPase activity at this stage in TN5-M6. According to the observation of immunohistochemistry, it showed the distribut ions of SPase, β-Amy, and α-Amy are related to starch granules deposition. In addition, α-Amy is also localized at tracheary elements (TEs).SS1 was more dominantly localized at TEs and peripheral cells in callus. Besides, SS1 mig ht be related to starch biosynthesis. On the other hand, SS2 and SS3 were les s detected and only localized at some specialized tissues and parenchyma. A B ound-IT-like antibody was used in this thesis. It localized at peripheral cel ls especially at the side attached culture medium. In addition, it closely re lated to somatic embryogenesis and organogenesis during shoot regeneration. When TN5 callus was induced in MSD10 medium containing anthranilic acid andAB A, it showed slower callus growth, lower cellular water content and osmotic po tential, and higher starch and soluble sugars contents. After being transferr ed to regeneration medium, it also showed higher glucose content and decreased starch and sucrose contents. All the phenomenons were similar to those under osmotic stress treatment. Higher IAA and ABA levels inhibited all the sucrol ytic enzyme (Sol-IT, Bound-IT, and SS) and amylase activity. Therefore, the hi gher soluble sugars and starch contents might be resulted fromsucrose uptaking by sucrose transporter dominantly and inhibiting starch degradation, respecti vely. In conclusion, osmotic stress induced some changes of carbohydrate meta bolism, and was brought about shoot regeneration. Part of those changes were regulated by changes of endogenous IAA and ABA levels. But there are some pro cesses induced by osmotic stress might be regulated by other factors during sh oot regeneration.
Cordeiro, Daniela Correia. "Natural variation in the response to chemically induced shoot regeneration in Arabidopsis thaliana (L.) Heynh." Master's thesis, 2017. http://hdl.handle.net/10316/83326.
Full textPlants are able to regenerate new organs from differentiated tissues cultivated in vitro. Adventitious shoot organogenesis has applications in plant transformation and in vitro propagation. In Arabidopsis thaliana, this can be achieved using root explants trough a two-step protocol, where new shoot meristems are induced by the conversion of lateral root-like primordia. However, this capacity is highly variable among natural accessions. Thus, the goal of this work was to gain insight into the phenotypic and genetic variation across a range of wild type Arabidopsis accessions with respect to shoot regeneration from root explants and to identify genetic factors involved in chemically enhanced shoot regeneration.To this end, 190 Arabidopsis accessions were analysed for their shoot regeneration capacity using two protocols, that reflect the most suitable conditions for C24 and Col-0 accessions, and in the presence and absence of an enhancer of shoot regeneration, here called compound C1. High variability was observed in the identity and number of structures formed and in the response to C1 among the different accessions tested, that ranged from recalcitrant to highly responsive ones. C1 was shown to promote shoot induction since its effect was positive in almost all accessions. Also, the conditions of Col-0 protocol proved to be more efficient, resulting both in a higher shoot regeneration index and a higher induced shoot numbers per explant than those of C24 protocol for most of the accessions. However, Lp2-2, Kar-1, Kyoto, Cen-0, C24, Bla-1, Gel-1, Etna-2 and Sapporo-0 had a regeneration rate higher than 90% in the presence of C1, regardless of the protocol used.Genome-Wide Association analyses revealed the occurrence of genetic variations (SNPs) associated with the differences in shoot regeneration phenotype and the response to C1. From these genetic variations, a large list of candidate genes was deduced, reflecting the complexity and broad polygenic basis of shoot regeneration. Nevertheless, five genes are noteworthy: WUS, ACS10, ERF061, MIR167C and IPS1. The finding of WUS – a gene commonly known to be important in the regenerative capacity – proved the veracity of this approach, while the discovery of ethylene-related genes ACS10 and ERF1 provides an incentive for the hypothesis that ethylene is involved in shoot regeneration, which has already been reported as well. MIR167C and IPS1, that regulates the activity of other miRNA, are also noteworthy genes since other miRNAs have been shown required for in vitro shoot regeneration. Furthermore, genetic variations around WUS, ACS10 and IPS1 were found to be associated with shoot regeneration from root explants in Arabidopsis regardless of the specific conditions that plants were subjected to, meaning that they are likely causal genes. Thus, our results suggest that changes in WUS, miRNAs and ethylene signalling or homeostasis might be responsible for the variation observed in the regenerative capacity and that C1 might boost this capacity by modulating these factors/processes. Nevertheless, all candidate genes need validation to know whether they are indeed causal genes. That can be done by gene knock-outs, complementation tests and/or using the CRISPR/Cas9 tool, a method for targeted genetic engineering by which a good allele can be inserted into a poorly performing background and see whether it improves regeneration.
As plantas podem regenerar novos órgãos a partir de tecidos diferenciados cultivados in vitro. A indução de organogénese é um processo com muitas aplicações na transformação genética de plantas e na propagação in vitro. Em Arabidopsis thaliana, isso pode ser conseguido usando explantes radiculares através de um protocolo de dois passos, onde novos meristemas caulinares são induzidos a partir de primórdios das raízes laterais. No entanto, esta capacidade é altamente variável entre genótipos. Assim, o principal objetivo deste trabalho foi analisar de que forma explantes radiculares de genótipos selvagens de Arabidopsis respondem à indução de organogénese e identificar fatores genéticos envolvidos na regeneração de rebentos potenciada por um composto químico em estudo.A resposta organogénica foi testada em 190 genótipos de Arabidopsis usando dois protocolos que refletem as condições mais adequadas para os genótipos C24 e Col-0, na presença e ausência de um potenciador da regeneração de rebentos: composto C1. Os resultados mostraram uma alta variabilidade no tipo e no número de estruturas formadas e na resposta ao C1 entre os diferentes genótipos testados, que variaram de linhas recalcitrantes a linhas com uma elevada resposta. Nas condições testadas, o composto C1 mostrou ser promotor da indução de rebentos, pois o seu efeito foi positivo em quase todos os genótipos. Além disso, as condições do protocolo Col-0 provaram ser mais eficientes pois resultaram num maior índice de regeneração de rebentos e induziram um maior número de rebentos por explante do que as do protocolo C24 para a maioria dos genótipos. Contudo, Lp2-2, Kar-1, Kyoto, Cen-0, C24, Bla-1, Gel-1, Etna-2 e Sapporo-0 apresentaram uma taxa de regeneração maior que 90% na presença de C1, independentemente do protocolo usado.As análises de genome-wide association revelaram muitas variações genéticas (SNPs) associadas a diferenças na regeneração de rebentos e à resposta ao C1. A partir dessas variações genéticas, uma lista grande de genes candidatos foi deduzida, refletindo a complexidade e a ampla base poligénica envolvida na regeneração de rebentos. Ainda assim, há cinco genes que merecem destaque: WUS, ACS10, ERF061, MIR167C e IPS1. O envolvimento de WUS - um gene comummente conhecido por ser importante na capacidade regenerativa - provou a veracidade desta abordagem, enquanto a descoberta de genes relacionados com a ação do etileno, ACS10 e ERF061, sugere que esta hormona possa estar envolvida na regeneração de rebentos, à semelhança do que é referido em alguns artigos. MIR167C e IPS1, que regula a atividade de outro miRNA, são também de destacar uma vez que outros miRNAs têm-se mostrado necessários para a regeneração de rebentos in vitro. Além disso, variações genéticas em redor dos genes WUS, ACS10 e IPS1 apresentaram-se associadas com a regeneração de rebentos através de explantes radiculares em Arabidopsis independentemente das condições a que as plantas foram sujeitas, significando que estes são provavelmente genes causais. No seu conjunto, os resultados obtidos sugerem que mudanças em WUS, miRNAs e na sinalização ou homeostase do etileno podem ser responsáveis pela variação observada na capacidade regenerativa e que C1 poderá aumentar essa capacidade modulando estes fatores/processos. Estes dados necessitam de confirmação futura de maneira a verificar se os genes candidatos são realmente genes causais. Esta validação pode ser feita por eliminação de genes, testes de complementação e/ou usando a abordagem CRISPR/Cas9, um mecanismo de edição genética que permite, por exemplo, inserir um bom alelo num background de pouca performance e ver se ele afeta positivamente a organogénese.
Outro - - Centro de Ecologia Funcional - Department of Plant Production, Faculty of Bioscience Engineering, Ghent University - Bolsa de estágio pelo programa Erasmus+
Wang, Miki Mei-Chi, and 王美琪. "Study on antioxidant pretreatment of explants and medium composition on shoot regeneration of Paphiopedilum orchids." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/45760219789092611123.
Full text國立中興大學
園藝學系所
104
Abstract Explant browning was frequently found to impede plant regeneration and multiplication during in vitro propagation of Paphiopedilum (Paph.) orchids. To reduce explant browning, lateral flower buds (LFBs) of Maudiae Type Paph. Hsinying Web ‘Giant’ × Paph. Pulsar ‘Hsinying Flame’ were presoaked with 100 mg∙L-1 ascorbic acid (AA) solution or ascorbic acid +kinetin (AA+KT) solution before surface sterilization. AA+KT was superior to AA alone in controlling explant browning of LFBs. After AA+KT pretreatment, LFB explants excised from young floral buds grew better than those from mature flowers with lower explant browning rate and higher shoot induction rate. Supplement of cysteine (Cys) in culture medium effectively decreased polyphenol oxidase (PPO) and phenylalanine ammonia lyase (PAL) activities of Paph. explants during early incubation. Particularly, the presence of 50 -100 mg∙L-1 Cys depressed Paph. explant PAL activities compared with the control groups, and thus greatly reduced phenolic compounds, such as coumaric acid. The reduction of phenolic substrates for PPO oxidization significantly prevented enzymatic browning in Cys-containing media and subsequently induced shoot multiplication and rooting in Paph. explants. Medium with high nitrogen salts exacerbated the incidence of Paph. explant browning, therefore alteration of NO3--N/NH4+-N ratio and nitrogen form in media were investigated. Removal of ammonia nitrate in MS medium positively reduced explant browning and beneficially improved the development of Paph. mericlonal propagation. In addition, potassium nitrate as a sole inorganic nitrogen source lowered the occurrence of Paph. explant browning and increased shoot multiplication.
Bao, Yanghuan. "Genome scale transcriptome analysis and development of reporter systems for studying shoot organogenesis in poplar." Thesis, 2008. http://hdl.handle.net/1957/8329.
Full textGraduation date: 2008
Smirnova, Tatiana. "Organogenesis in Vitro under Altered Auxin Signaling Conditions." Thesis, 2012. http://hdl.handle.net/1807/42900.
Full textLin, Jia Rong, and 林家榮. "Shoots regeneration via rhizome explants of C. sinense‘Shi-Ba Xyue-Shi’×C.formosanum." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/06861880172774369244.
Full textNontapotIssariyakul and 余大城. "Osteochondral Regeneration using PLGA Scaffolds under Short-term Continuous Passive Motion in a Rabbit Model." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/36827635340807420116.
Full textChen, Po Yu, and 陳勃聿. "Induction of multiple shoots from the immature embryos of interspeciefic hybrids by Thidiazuron and plants regeneration in peanut." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/19979201804607649763.
Full text國立中興大學
農藝學系
90
Summary The immature embryos of interspecific hybrids between cultivar TN11 and six wild type(A. cardenasii, A. rigonii, A. chacoense, A. corrotina, A. spegazzinii and A. monticola) were cultured on MS+4 mg/l TDZ to induce multiple shoot and bud primordia. The collected bud and bud primordia was them used to investigate the effects of TDZ on shoots induction and proliferation, and to establish plant regeneration technique. The results were summarized as follows: 1. Buds of six interspecific hybrids cultured on MS medium containing different TDZ concentrations to induce multiple shoot. The induced percentage of shoot were significantly different among TDZ levels and crosses, but the averaged shoots were non-significant different. The mean numbers of bud primordia cultured on MS media supplemented with TDZ were significantly higher than on MS medium. Bud primordia cultured on MS media containing TDZ could induce shoots, but the efficiency was lower than buds as explants. 2. In all crosses, the induced percentage of shoot induced from shoot through three times subculture on MS+2 mg/l TDZ medium could maintain above 50%, and the averaged shoot was stabilized. 3. TDZ induced the small and thickened multiple shoots, but MS medium without TDZ could increase the induced percentage of shoot and obtained normal shoots. Shoots subcultured with the MS medium without TDZ have the higher rooting percentage compare to MS medium containing TDZ, and root system was more healthy. 4. If the shoots of six interspecific hybrids transferred to MS media containing 50 mg/l ascorbic acid and three levels of NAA, the rooting percentage increased with NAA concentration. The MS medium containing 0.5 mg/l NAA produced the highest percentage of rooting and have more healthy root system. The percentage of rooting of all interspcific crosses were reduced with the subculture generation increased. 5. The recovery percentages of the rooted plantlets were ranged from 32.16% to 54.66% in six interspecific crosses. These plants were demonstrated as interspecific hybrids by chromosome number and morphological characteristics.
Li, Ren-Hong, and 李仁宏. "The Study on Short – term Employment Promotion Community Satisfaction in Rural Regeneration Communities - A Case Study of Tainan, Kaohsiung and Pingtung Country." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/81523465200486864464.
Full text長榮大學
土地管理與開發學系碩士班
99
By the influence of financial tsunami, the economical industry of our country takes serious effect. The domestic unemployment rate rises higher gradually. Therefore Soil and Water Conservation Bureau decide to subsidize those legal community organizations or associations of countryside which aren’t located on urban planning area, to accelerate impetus of the countryside regeneration, to provide employment opportunity. The manpower of countryside will be full effective utilization and slow down the situation of high unemployment rate, namely “Accelerate the regeneration of short-term promotion of employment in rural areas” Interview Survey and document analysis as a research tool. Research data and relevant information are from interview of participations who are community director and workers. Assisted by ATLAS.ti qualitative analysis software, researchers found that the results supporting. This study found that “Accelerate the regeneration of short-term promotion of employment in rural areas” can provide reorganization of community, manpower as well as the related item, and it can increase the numbers of short-time job opportunity to reduce the impact which the unemployment brings, furthermore it may increase the countryside regeneration and the activation, employee's work degree of satisfaction belongs to satisfaction as well as the will of employment universal enhancement, community director and the employee measure degree of satisfaction belongs to satisfaction. Accelerate the regeneration of short-term promotion of employment in rural areas is labor intensive which is unable to strengthen the employment ability and to learn new skill. Accelerate the regeneration of short-term promotion of employment in rural areas.
Russo, Teresa Lopes. "Nova vida no palacete amarelo ao Chiado: estudo de caso de investimento imobiliário." Master's thesis, 2012. http://hdl.handle.net/10071/5463.
Full textIn 1880, when Eça de Queiroz wrote “O Mandarim”, certainly, he wouldn’t imagined that his Yellow Palace in Loreto (the actual “Valada e Azambuja” Palace) where took place some of Lisbon’s most famous parties, would became, more than 130 years later, a residential enterprise, focus on the short term rentals. The actual “Valada e Azambuja” Palace suffered an urban regeneration intervention made by a Real Estate Investment Fund, the “Santa Casa 2004” Fund, managed by FundBox – Sociedade Gestora de Fundos de Investimento Imobiliário, SA. This work intends to study this urban regeneration, through a guideline between the following themes: Real Estate Market, Urban Regeneration and Real Estate Investment Funds. It’s relevant to show the importance of Real Estate Investment Funds as an active and credible mean in the Urban Regeneration and the importance of Urban Regeneration in the Real Estate Market. The development of this analysis allows to see that the using of fiscal incentives in Urban Regeneration may be fundamental, mainly in the actual context, in which there are strong restrictions to the public spending, mostly in the selling level, profitability and the access to credit needed to finance the activity. Therefore, it was selected a practical case study of Urban Regeneration. This example includes the intervention on the “Valada e Azambuja” Palace, developed in Lisbon’s historical center. The project has ten apartments focus on tourism.
Thatcher, J., and Liz Sharp. "Measuring the Local Economic Impact of NHS Procurement in the UK: An Evaluation of the Cornwall Food Programme and LM3." 2008. http://hdl.handle.net/10454/1046.
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