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1
Jacobowitz, Joseph(Joseph R. ). "Reverse genetic approaches reveal gene redundancy in Arabidopsis anthers". Thesis, Massachusetts Institute of Technology, 2020. https://hdl.handle.net/1721.1/129041.
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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Biology, 2020Cataloged from student-submitted PDF of thesis.
Includes bibliographical references.
When aquatic plants migrated to land 500 million years ago, they were met with harsh conditions associated with terrestrial life, such as dry air, high radiance light, and high effective gravity. Early plants of this time period underwent rapid evolution to develop novel plant traits to mitigate these challenges - these traits remain highly conserved in modern land plants. Among the most important of these traits is the biosynthesis of a unique polymer known as sporopollenin, which protects the vulnerable plant spore and pollen grain. Sporopollenin is considered to be the toughest known biopolymer and although chemists and botanists have studied this remarkable material for over a century, relatively little is known about sporopollenin compared to other major plant biopolymers. In this thesis, I employ reverse genetic approaches to identify novel Arabidopsis genes that are responsible for sporopollenin biosynthesis. With these methods, I identify a previously unstudied gene, hereby known as IPE2 , which acts redundantly with IPE1 in the synthesis of sporopollenin. Additionally, I identify two unstudied peroxidases, PRX9 and PRX40 , which are also redundant and critical for pollen development, although these are not involved in sporopollenin and instead crosslink cell wall extensin proteins. These works enhance our understanding of the pollen wall and of pollen development. Moreover, this work reveals the untapped potential of reverse genetics to predict redundant relationships between paralogs in well-studied model organisms.
by Joseph Jacobowitz.
Ph. D.
Ph.D. Massachusetts Institute of Technology, Department of Biology
2
Kalantidis, Kriton. "Studies of mitochondrial gene expression in fertile and male sterile Arabidopsis thaliana". Thesis, University of Nottingham, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.282714.
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Rethwisch, Michael D., Manuel M. Luna, D. Michael Ramos, Jessica J. Wellman y Michael T. Williams. "Pistil and Style Elongations Beyond the Anthers: Results From 2005 Field Experimentation". College of Agriculture, University of Arizona (Tucson, AZ), 2006. http://hdl.handle.net/10150/198202.
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A rapid heat increase from the high 80s-low 90s to high temperatures of 110o F on May 21 and 22, 2005, was recorded in the Blythe, CA, area, resulting in abnormal cotton flowers in mid-June, being especially characterized by elongated styles and stigmas being beyond the anthers. Two different cotton variety trials conducted in the Palo Verde Valley allowed data to be collected semi-weekly beginning June 17-20, with 100+ flowers per plot examined in each plot (four replications) of each of the 14 cotton variety entries. Every cotton variety had an average of 90+% of flowers expressing heat stress abnormalities (elongated styles) at the beginning of data collection even though the trials varied by planting date and location. Abnormal flowers were noted for several weeks, with some stigmas 21 mm beyond the anthers. Varieties differed in their responses to heat stress as measured by elongation later in the summer. Limited data were also collected for fruit retention and correlated with length of stigma extension beyond anthers. Retention percentages decreased as distance between anthers/stigmas increased, however boll size increased with less retention, possibly through nutrient partitioning. Various foliar fertilizers containing calcium were also evaluated for their effect on stigma elongations of DPL 449BR cotton. Significant differences existed for stigma elongations, with 2.5 qts./acre of CalMax resulting in statistical reduction of elongation when compared with the untreated check at 3 weeks after application. Statistical differences did not exist at four weeks although statistical differences did exist at this date for the percentage of flowers affected, with the highest percentage (81.7%) noted in untreated cotton.
4
Taylor, Andrew Alexander. "Immunological characterization of a putative serine protease expressed in anthers of Lilium longiflorum". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0020/MQ28737.pdf.
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Yamaguchi, Tomoya. "Analysis of genes expressed in rice anthers during the stage of maximal chilling sensitivity". Kyoto University, 2006. http://hdl.handle.net/2433/144084.
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Kyoto University (京都大学)0048
新制・論文博士
博士(農学)
乙第11846号
論農博第2600号
新制||農||929(附属図書館)
学位論文||H18||N4158(農学部図書室)
24388
UT51-2006-J543
(主査)教授 關谷 次郎, 教授 矢﨑 一史, 教授 河内 孝之
学位規則第4条第2項該当
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Wenzel, Carol Lorraine Carleton University Dissertation Biology. "Development of anthers and pollen grains of Brassica Napus L.; a histological and histochemical study". Ottawa, 1991.
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Prusicki, Maria Ada [Verfasser] y Arp [Akademischer Betreuer] Schnittger. "Live cell imaging of meiosis in anthers of Arabidopsis thaliana / Maria Ada Prusicki ; Betreuer: Arp Schnittger". Hamburg : Staats- und Universitätsbibliothek Hamburg, 2019. http://d-nb.info/1192442814/34.
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Prusicki, Maria Ada Verfasser] y Arp [Akademischer Betreuer] [Schnittger. "Live cell imaging of meiosis in anthers of Arabidopsis thaliana / Maria Ada Prusicki ; Betreuer: Arp Schnittger". Hamburg : Staats- und Universitätsbibliothek Hamburg, 2019. http://nbn-resolving.de/urn:nbn:de:gbv:18-98605.
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NGUYEN, Ngoc Giao. "Effects of Water Deficit on Pollen Development in Rice". Thesis, The University of Sydney, 2008. http://hdl.handle.net/2123/2804.
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Rice (Oryza sativa L.) is very susceptible to water deficit at any time during its life cycle as a semi-aquatic cereal crop. However, the consequential damage is particularly severe if water deficit occurs during reproductive phases. The conspicuous injury often observed in rice plants exposed to water stress during meiosis of the pollen mother cell is the reduction of grain set, which is attributed to the decline of male fertility. In spite of much research on drought-induced male sterility in rice, the underlying mechanisms of the problem are poorly understood. This project was therefore conducted to investigate the molecular mechanisms of water deficit-induced pollen sterility in rice. In this study three consecutive days of water deficit treatment at -0.5 MPa osmotic potential during anther development effectively reduced the leaf water potential (leaf) and the number of viable pollen which later led to a decrease in grain set. Moreover, this thesis demonstrates that the immediate deleterious effects of water deficit to plant fertility could be estimated using a young microspore viability index, which showed a strong correlation with mature viable pollen and grain set. The present work has also illustrated that oxidative stress appears to be a plausible cause for the decline of male fertility and grain set. Water deficit has induced the excessive production of reactive oxygen species (ROS) above the redox balance, which in turn caused detrimental effects to cellular DNA and might result in programmed cell death (PCD) in the anthers. Moreover, ROS accumulation effectively influenced ATP synthesis leading to a decrease in the level of ATP in the anthers. Excessive ROS accumulation after drought could be the consequence of insufficient activity of the antioxidant system, which has been illustrated by qRT-PCR expression analysis of major antioxidant genes. Down-regulation of those genes would increase the incidence of oxidative damage. In contrast, stable or up-regulated expression of these genes resulted in less oxidative damage. Detailed investigations of sugar metabolism in anthers has provided supplemental data to develop a model of sugar unloading and transport within anther using in situ hybridisation to mRNA techniques. Analysis of sugar transportation within the cellular compartments of anther has unveiled the role of sugar metabolism on pollen sterility in rice. qRT-PCR assays of genes associated with the sugar metabolic pathway has demonstrated that the supply of both sucrose and hexoses from the anther walls to the locules was not restricted after water deficit stress. The results indicate that water deficit might not cause sugar starvation for developing microspores as previously thought, nor inhibit the initial steps of sugar utilisation such as glycolysis. This thesis has suggested new ideas regarding the role of rising sugar levels to cope with oxidative stress in anthers. Sugar accumulation might have provided protection against oxidant damage by strengthening the antioxidant system. However, the interplay between sugar and oxidative stress is not straightforward and needs to be further characterised. In-depth investigations on the interaction between sugar signalling and oxidative stress responses may help indentify the role of sugars in protecting anthers under water deficit. Although many studies on drought and chilling stresses in rice anthers have been performed, the causal mechanism of male sterility still remains to be elucidated. Findings presented in this thesis may contribute to understanding molecular mechanisms of male sterility in rice as a response to drought stress. A more detailed investigation of mitochondrial respiration in rice anthers is required to further examine this problem. Finally, this thesis suggests that signalling molecules such as 14-3-3 proteins and abscisic acid (ABA) might act upstream of ROS production and antioxidant defence in plants. Further work on these molecules might therefore further illustrate how they influence plant fertility under water shortage conditions.
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NGUYEN, Ngoc Giao. "Effects of Water Deficit on Pollen Development in Rice". University of Sydney, 2008. http://hdl.handle.net/2123/2804.
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Doctor of PhilosophyRice (Oryza sativa L.) is very susceptible to water deficit at any time during its life cycle as a semi-aquatic cereal crop. However, the consequential damage is particularly severe if water deficit occurs during reproductive phases. The conspicuous injury often observed in rice plants exposed to water stress during meiosis of the pollen mother cell is the reduction of grain set, which is attributed to the decline of male fertility. In spite of much research on drought-induced male sterility in rice, the underlying mechanisms of the problem are poorly understood. This project was therefore conducted to investigate the molecular mechanisms of water deficit-induced pollen sterility in rice. In this study three consecutive days of water deficit treatment at -0.5 MPa osmotic potential during anther development effectively reduced the leaf water potential (leaf) and the number of viable pollen which later led to a decrease in grain set. Moreover, this thesis demonstrates that the immediate deleterious effects of water deficit to plant fertility could be estimated using a young microspore viability index, which showed a strong correlation with mature viable pollen and grain set. The present work has also illustrated that oxidative stress appears to be a plausible cause for the decline of male fertility and grain set. Water deficit has induced the excessive production of reactive oxygen species (ROS) above the redox balance, which in turn caused detrimental effects to cellular DNA and might result in programmed cell death (PCD) in the anthers. Moreover, ROS accumulation effectively influenced ATP synthesis leading to a decrease in the level of ATP in the anthers. Excessive ROS accumulation after drought could be the consequence of insufficient activity of the antioxidant system, which has been illustrated by qRT-PCR expression analysis of major antioxidant genes. Down-regulation of those genes would increase the incidence of oxidative damage. In contrast, stable or up-regulated expression of these genes resulted in less oxidative damage. Detailed investigations of sugar metabolism in anthers has provided supplemental data to develop a model of sugar unloading and transport within anther using in situ hybridisation to mRNA techniques. Analysis of sugar transportation within the cellular compartments of anther has unveiled the role of sugar metabolism on pollen sterility in rice. qRT-PCR assays of genes associated with the sugar metabolic pathway has demonstrated that the supply of both sucrose and hexoses from the anther walls to the locules was not restricted after water deficit stress. The results indicate that water deficit might not cause sugar starvation for developing microspores as previously thought, nor inhibit the initial steps of sugar utilisation such as glycolysis. This thesis has suggested new ideas regarding the role of rising sugar levels to cope with oxidative stress in anthers. Sugar accumulation might have provided protection against oxidant damage by strengthening the antioxidant system. However, the interplay between sugar and oxidative stress is not straightforward and needs to be further characterised. In-depth investigations on the interaction between sugar signalling and oxidative stress responses may help indentify the role of sugars in protecting anthers under water deficit. Although many studies on drought and chilling stresses in rice anthers have been performed, the causal mechanism of male sterility still remains to be elucidated. Findings presented in this thesis may contribute to understanding molecular mechanisms of male sterility in rice as a response to drought stress. A more detailed investigation of mitochondrial respiration in rice anthers is required to further examine this problem. Finally, this thesis suggests that signalling molecules such as 14-3-3 proteins and abscisic acid (ABA) might act upstream of ROS production and antioxidant defence in plants. Further work on these molecules might therefore further illustrate how they influence plant fertility under water shortage conditions.
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Grunewald, Stephan [Verfasser], Thomas Gutachter] Vogt, Ingo [Gutachter] [Heilmann y Enrico [Gutachter] Martinoia. "Biosynthesis and transport of flavonol sophorosides in Arabidopsis thaliana anthers / Stephan Grunewald ; Gutachter: Thomas Vogt, Ingo Heilmann, Enrico Martinoia". Halle (Saale) : Universitäts- und Landesbibliothek Sachsen-Anhalt, 2021. http://d-nb.info/1237685729/34.
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Dennis, Ruth. "Analysis of anther dehydration : a process required for anther dehiscence and pollen release". Thesis, University of Nottingham, 2018. http://eprints.nottingham.ac.uk/49599/.
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In flowering plants, the opening of the anther to release pollen is carefully timed to maximise reproductive potential. Manipulation of this process is an important tool for plant breeding and the production of hybrid crops. Dehydration of the anther epidermis, combined with the presence of secondary thickening within the endothecium layer, is required to create biomechanical changes that enable anther dehiscence. Both passive and active processes contribute to the targeted removal of water from the anther walls, however the genetic factors controlling water movement are not known. Furthermore, the presence of stomata on anthers may enhance water loss via evaporation. In plants, active movement of water can be achieved by regulation of water channels and by changes to the osmotic potential of organs; this was explored in the context of changes in the anther driving anther dehiscence and pollen release. qRT-PCR analysis was used to identify aquaporin and sucrose transporter genes that are upregulated during anther dehiscence in Arabidopsis thaliana. For genes of interest, the phenotypes of available mutants were characterised. Combinations of single, double and triple mutants showed changes in fertility and variations in floral organ lengths. Analysis of GUS reporter lines showed that the promoter activity of different aquaporins is confined to specific parts of the flower. The results suggest that certain aquaporins isoforms enhance hydraulic conductivity in different parts of the flower, which could contribute to water transport required for petal and filament extension. The importance of evaporation during anther dehydration was also investigated. The phenotypes of Arabidopsis mutant lines with varying stomatal densities were characterised, and changes in fertility were investigated under different environmental conditions. High relative humidity delayed anther dehiscence and affected pollen viability, resulting in reduced fertility. Plants that have no anther stomata were most severely affected. These results suggest that water loss via evaporation is important for anther opening in Arabidopsis, and that the presence of stomata on anthers facilitates this process.
13
Higgins, Patricia. "Embryogenesis in barley anther culture". Thesis, University of Leeds, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.235487.
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Frappell, Deidre E. "Anther culture of Australian wheats". Adelaide Thesis (Ph.D.) -- University of Adelaide, Department of Plant Science, 1993. http://hdl.handle.net/2440/21655.
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Frappell, Deidre E. "Anther culture of Australian wheats". Thesis, Adelaide Thesis (Ph.D.) -- University of Adelaide, Department of Plant Science, 1993. http://hdl.handle.net/2440/21655.
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Mayo-Harp, Maria Isabel. "National anthems and identities, the role of national anthems in the formation process of national identities". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ61588.pdf.
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Fernández, José. "Anther and pollen development in barley". Thesis, University of Nottingham, 2012. http://eprints.nottingham.ac.uk/13916/.
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The control of pollen viability and release is of major commercial importance in the development of crops for hybrid seed production and selective breeding. It has been shown that key transcription factors in Arabidopsis particularly MALE STERILITY1 (MS1), are functionally conserved in rice (Li et al., 2011), therefore extending this comparative analysis and controlling fertility in temperate cereals, such as barley, is the long term goal of this project. Although anther and pollen development of barley seems morphologically similar to Arabidopsis, the genes involved and how they are regulated are currently unknown. Arabidopsis MS1 is a tapetum specific transcription factor which is expressed exclusively from the tetrad stage to early microspores release. Identification and accurate staging of barley anther development is essential for expression analysis and functional characterisation of genes involved in pollen development. Therefore, a complete morphological study of barley development was conducted. External characteristics have been described in parallel to anther development in order to predict anther stages by the observation of external stages phenotypic traits. Characterization of the barley orthologue of MS1 (HvMS1) has been conducted. Recently a new grass genome has been released, Brachypodium distachyion. This new resource has been used to aid primers design alongside the rice OsPTC1 sequence, the orthologue of MS1 (Li et al., 2011). Genome sequencing has indicated that the Brachypodium genus is more closely related to wheat and barley than it is to rice, Due to the close relationship between Brachypodium and barley, this new grass has been used as intermediary to identify the OsPTC1 orthologue in barley as well as downstream MS1 targets. A highly similar sequence to OsPTC1 was found in Brachypodium, Bradi4g31760. This new gene, as a result of its similarities to OsPTC1, was considered as its putative orthologue gene in Brachypodium. Therefore, the most conserved areas between OsPTC1-Bradi4g31760 were used for primers design to successfully amplify equivalent gene in barley (HvMS1). The characterization of this barley gene showed a similar expression pattern to the MS1 putative orthologue in Arabidopsis of tapetum specific expression. In addition, RNAi silencing of this gene has revealed that it is essential for the normal development of pollen, with a lack of viable pollen produced in the putative HvMS1 silenced transgenic lines.
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Batty, N. P. "Anther cultivation of Solanum tuberosum L". Thesis, University of East Anglia, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.377711.
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Clifford, Zachary Lee. "Anthem". Kent State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=kent1574675376205461.
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Mitchell, Mark Lanyon. "A stylistic study of the anthems of Herbert Howells together with a catalogue of the anthems and evening canticles". Master's thesis, University of Cape Town, 1994. http://hdl.handle.net/11427/7847.
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Bibliography: leaves 177-191.The biographical chapter gives a basic overview of Howells' life. Particular attention has been paid to teaching and church appointments, as the connection with the church was the main influence on his creative processes. This and other (direct or indirect) influences on Howells' creative process are discussed in the chapter following the Biography. The chapter on style focuses on Howells' technique of composition. As Howells acknowledged that Tudor music was a fundamental influence on his writing, aspects of his style that might have been particularly influenced are discussed. Very little analytical study of Howells' anthems has been undertaken to date. For the purpose of this dissertation, all the anthems have been studied and analysed in detail, but only a selection of works representative of his style have been used for the purpose of musical exemplification.
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Tang, Lee-kwan. "Functional characterization of an Arabidopsis anther-specific gene encoding a dihydrolavonol 4-reductase-like protein". Click to view the E-thesis via HKUTO, 2009. http://sunzi.lib.hku.hk/hkuto/record/B41633891.
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Bye, Nicholas. "Anther culture and cytogenetic studies in Cochlearia". Thesis, University of Liverpool, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.329383.
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Venkatanagappa, Shoba. "Cytogenetic manipulation and anther culture of wheat". Thesis, Faculty of Agriculture, 1993. https://hdl.handle.net/2123/11992.2.
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The experiments in this thesis manipulated the breeding system of wheat and triticale first toward outcrossing with male sterility systems, and then toward homozygosity with anther culture systems.
To provide a visible marker that could be used to distinguish male-sterile plants from male-fertile plants, 'chromosome engineering' was attempted via two distinct crossing procedures to generate two translocation chromosomes, 5AL.5AS-5RS and 4EL-5AS. These would then be recombined (via an intercrossing procedure) into another translocation chromosome 4EL.5AS—5RS which would link the blue aleurone gene Ba on chromosome 4EL with the dominant male sterility allele Ms3 on chromosome arm SAS, while chromosome arm segment SRS would prevent pairing and crossing over with other SAS arms in heterozygous breeding lines.
The procedure to develop the first translocation chromosome consisted of crossing dominant male-sterile (DMS) Selkirk wheat with the 5R(5A) substitution line in Chinese Spring wheat. The progeny were further crossed with ph1b mutant in Chinese Spring wheat to allow homoeologous pairing and recombination to occur between chromosomes 5A and 5K Morphological, cytological and genetic markers were used to evaluate the progeny derived from these crosses. The required traits were 1. Presence of 2n = 41, 2. Speltoid heads indicating monosomy for chromosome 5A 3. Sterile anthers indicating the presence of M33. 4. Presence of B-Amy—AZ bands and IBF bands indicating the presence of chromosome arm SAL. 5. Lack of 'hairy neck' phenotype, B-Amy-R2 and [bf—R1 bands indicating the absence of chromosome arm SRL. 6. Positive dot-blot for the rye-specific DNA probe indicating the likely presence of a rye segment or arm from chromosome arm 5R8. One progeny which had a combination of these characteristics was consistent with the required translocation chromosome.
The procedure for the second translocation chromosome involved crossing DMS-Selkirk with the chromosome 4E addition line 'Blue Tordo' and backcrossing with N5AT5D in Chinese Spring. This enabled the maintenance of chromosomes 5A and 4E as monosomes thus providing an opportunity for them to misdivide and reunite (centric fusion). The progeny were evaluated using morphological and cytological markers. The required characters were 1. Blue seed color. 2. Sterility of anthers. 3. Speltoidy of heads. 4. 2n = 42 chromosomes. The results obtained indicated that although one plant with most of the above mentioned traits was recovered, its anthers were partially fertile. In addition, M33 segregated independently of Ba indicating that the required translocation chromosome was not obtained. The restoration of partial fertility is the first instance of partial restoration of DMS which was previously considered to be obligate male sterility.
In general it is recommended that the translocation obtained from the first crossing procedure be further confimed by analyses with the C-banding technique or by in situ hybridization methods to confim the presence of chromosome arm SRS and to evaluate the length of rye segment. Further, alternative sources of the blue aluerone marker such as T. boeoticum should also be investigated.
The potential for using the DMS gene Ms3 in triticale was also investigated. Wheat-rye amphihaploids derived from crosses between Selkirk DMS wheat and four rye populations (Chapter 4) were treated with colchicine, and DMS triticales were derived from only two S. cereale selections. Male sterility was expressed in both wheat-rye amphihaploids as well as in primary and secondary triticales inspite of the presence of rye chromosomes. The stability of expression of male sterility in these triticales indicated that dominant male sterility could be used in breeding programs.
Experiments to enhance the efficiency of anther culture for use as a wheat breeding tool were conducted using cv. Grebe and MC17 medium as model systems. The media were modified using alternative support substrates, carbohydrate sources and plant growth regulators. The data quantified were induction of embryoids, direct plant production, green and albino plant regeneration, proportion of green plants to total regenerants. In addition, the survival of green regenrants upon transfer to soil was evaluated together with the seed set obtained probably due to spontaneous doubling.
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Venkatanagappa, Shoba. "Cytogenetic manipulation and anther culture of wheat". Phd thesis, Faculty of Agriculture, 1993. http://hdl.handle.net/2123/11992.
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Smith, Martha Josephine Dick. "A choral director's guidebook to Handel's anthems : an historical and musical perspective /". Access Digital Full Text version, 1987. http://pocketknowledge.tc.columbia.edu/home.php/bybib/10779176.
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Crossley, Susan Jane. "Anther development in Lilium henryi : a molecular study". Thesis, University of Reading, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.315391.
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Zare, Abbas Ghamari. "Anther culture in intergeneric hybrids of forage grasses". Thesis, University of Liverpool, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.417963.
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Hird, Diane Lee. "Characterisation of an anther-specific β-1,3-glucanase". Thesis, University of Leicester, 1995. http://hdl.handle.net/2381/35465.
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A critical stage in pollen development is the separation of the microspores following meiosis. In almost all angiosperms the pollen mother cell and resultant microspores are encased in a thick callose wall. At the appropriate developmental stage, the surrounding tapetal cells secrete callase, a complex of beta-1,3-glucanases, which hydrolyse this callose wall. The free microspores then continue their development into mature pollen grains. A Brassica napus cDNA, A6, and two corresponding Arabidopsis thalimin genomic clones, G61 and G62, had been isolated. The A6 cDNA exhibited sequence similarity to beta-1,3-glucanases and was known to be present at the time of microspore release. It was proposed that A6 may represent a component of callase. The scope of this thesis was to characterise the A. thaliana genomic clones with a view to understanding their role in microsporogenesis, and in particular whether they are involved in the crucial process of microspore release. Due to the high degree of sequence similarity between the two genomic clones, work was concentrated on G62. The G62 sequence was compared to beta-1,3-glucanases and found to be similar, but distinct from them. The temporal and spatial expression pattern of G62 was investigated using promoter fusions. It was found to be tapetum-specific and present during the developmental window of callase activity. The enzymatic nature of both A6 and G62 were investigated in an Escherchia coli over-expression system and in planta. No activity was associated with the A6 protein when over-expressed in E. coli, or with the G62 protein when expressed in Nicotiana tabacum. The most likely explanation for these findings was that both A6 and G62 were found to lack an essential catalytic residue.
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Teparkum, Sirasak. "Embryogenic response of potato anther culture to colchicine". Thesis, This resource online, 1996. http://scholar.lib.vt.edu/theses/available/etd-08292008-063430/.
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Silva, Carla Maria de Jesus. "Indu??o de calos em anteras e poliploidia em gen?tipos de melancia". Universidade Estadual de Feira de Santana, 2018. http://tede2.uefs.br:8080/handle/tede/tede/631.
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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES
The watermelon (Citrullus lanatus) is a very important vegetable for a region of Northeast Brazil due to its adaptation as the natural conditions and the good characteristics of the fruit that are obtained. The aims of the current study are to assess watermelon genotype responses to calluses in anthers by using growth and temperature regulators, and to induce polyploidy through colchicine use (at different concentrations), exposure time, mechanical scarification and application methods. Anthers of Smile and Sugar Baby lines were inoculated in MS medium at different concentrations of 2.4-D or of BAP with 2.4-D, in combination with the pre-treatment (low temperature). Crimson Sweet cultivar seedlings were treated with different colchicine concentrations at two different times, with and without scarification, in order to induce polyploidy. Line LDRO was subjected to different colchicine concentrations at two different times and application methods: a) direct in the seed method (with, and without, scarification) (DSM, WE and WOE), b) Radicle emission method (ERM), c) Hypocotyl and root insertion point method (HRIM), d) At the apex of the seedling method (ASM) and e) Inverted hypocotyl method (IHM). Crimson Sweet flower buds were subjected to colchicine, at two different times, in order to induce polyploidy. Results have shown that 2.4-D often induced callus formation in both lines, but BAP/2.4-D interaction and pre-treatment did not increase the induction frequency. Crimson Sweet showed higher induction rate at 0.2% colchicine for 48h, WE. Line LDRO presented plants with tetraploid cells at 0.2% colchicine for 24 and 48h. The method 0.2% DSM, WE and WOE also generated plants with tetraploid cells. The diameter of treated pollen grains in flower buds have increased; the higher rate of non-reduced gametes induction was 16.07% and flower bud diameter (1.5mm) was estimated as adequate for induction
A melancia (Citrullus lanatus) ? uma hortali?a muito importante para a regi?o Nordeste do Brasil por sua adapta??o as condi??es clim?ticas e pelas boas caracter?sticas de fruto que se obt?m. Os objetivos desse trabalho foram avaliar as respostas de gen?tipos de melancia quanto ? indu??o de calos em anteras utilizando reguladores de crescimento e temperatura; e induzir a poliploidia mediante o uso da colchicina em diferentes concentra??es, tempos de exposi??o, escarifica??o mec?nica e m?todos de aplica??o. Anteras das linhagens de Smile e Sugar Baby foram inoculadas em meio MS sob diferentes concentra??es de 2,4-D ou BAP com 2,4-D, associado ao pr?-tratamento (baixa temperatura). Para indu??o de poliploidia, sementes da cultivar Crimson Sweet foram tratadas com diferentes concentra??es de colchicina, em dois tempos, com e sem escarifica??o. Para a linhagem LDRO, utilizaram-se diferentes concentra??es de colchicina em dois tempos e m?todos de aplica??o: a) M?todo direto na semente (com escarifica??o e sem escarifica??o) (MDS, CE e SE), b) M?todo da semente com emiss?o da rad?cula (MER), c) M?todo no ponto de inser??o do hipoc?tilo e raiz (MIHR), d) M?todo no ?pice da pl?ntula (MAP) e e) M?todo do hipoc?tilo invertido (MHI). Na indu??o de poliploidia em bot?es florais de Crimson Sweet utilizou-se colchicina em dois tempos. Os resultados mostraram que o 2,4-D induziu a maior frequ?ncia de calos nas duas linhagens, a intera??o BAP com 2,4-D e o pr?-tratamento, n?o aumentaram a frequ?ncia de indu??o. Para Crimson Sweet, o maior percentual de indu??o foi obtido com colchicina a 0,2% por 48 h, SE. Para LDRO, observou-se uma frequ?ncia de plantas com c?lulas tetraploides com colchicina a 0,2% por 24 h e 48 h. Nos m?todos 0,2% MDS CE e MHI observou-se tamb?m plantas com c?lulas tetraploides. Em bot?es florais, o di?metro dos gr?os de p?len tratados aumentou; o maior percentual de indu??o de gametas n?o reduzidos foi de 16,07% e; o di?metro em torno de 1,5 mm do bot?o floral foi estimado como adequado para indu??o
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Tintoc, Robert V. "An artist's anthem /". Diss., [La Jolla] : University of California, San Diego, 2010. http://wwwlib.umi.com/cr/ucsd/fullcit?p1474767.
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Thesis (M.F.A.)--University of California, San Diego, 2010.Images in accompanying supplemental files document the author's stage design in 6 UCSD Dept. of Theatre & Dance productions. Available via ProQuest Digital Dissertations. A play. Images in accompanying supplemental files document the author's stage management of the February 2008 UCSD Dept. of Theatre & Dance performance of Tango, a play by Rabindranath Tagore. Title from first page of PDF file (viewed May 14, 2010).
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Fenderson, Mark. "An interpretive analysis of George Antheil's Sonata for trumpet and piano". Thesis, connect to online resource, 2008. http://digital.library.unt.edu/permalink/meta-dc-9105.
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Thesis (D.M.A.)--University of North Texas, 2008.System requirements: Adobe Acrobat Reader. Accompanied by 4 recitals, recorded Oct. 17, 2005, Mar. 27, 2006, June 4, 2007, and Apr. 14, 2008. Includes bibliographical references (p. 43-44).
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Vizcay-Barrena, Gema. "Functional analysis of ms1 during anther development in arabidopsis". Thesis, University of Nottingham, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.415917.
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Mo, Rui. "Characterising the regulatory network of MYB26 during anther dehiscence". Thesis, University of Nottingham, 2017. http://eprints.nottingham.ac.uk/39683/.
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Pollen development and release involves a number of important stages, which govern the success of fertilisation and thus indirectly crop yields. The secondary cell wall in the anther plays a pivotal role in anther dehiscence by offering mechanical strength required for opening and pollen release (Wilson et al. 2011). MYB26/MALE STERILE35(MS35) is a key regulator of the secondary thickening development in anther, mutation of this gene results in a failure of anther dehiscence and functional male sterility (Steiner-Lange et al. 2003; Yang et al. 2007). However, the regulatory network of MYB26 remains to be fully identified. To address this issue, the MYB26 direct targets and interactive proteins were investigated. Putative targets of MYB26 were selected, based on their expression patterns, from previously determined expression profiles of the ms35 mutant (Song, 2009). PKSP, a receptor-like cytoplasmic kinase (RLCK) was co-expressed with MYB26. Chromatin immunoprecipitation (ChIP)-PCR indicated that MYB26 may bind to the first intron of PKSP. The NAC SECONDARY WALL–PROMOTING FACTOR1 (NST1) and NST2 genes have been demonstrated as direct targets of MYB26 in ChIP-PCR. However, electrophoretic mobility shift assay (EMSA) did not show binding and retardation, possibly due to the requirement of additional proteins to facilitate MYB26 binding. MYB26 interactive proteins were investigated using the yeast two-hybrid system (C.Yang, Z.A.Wilson, unpublished data) and Förster resonance energy transfer (FRET) assays. Y2H560, a CHY-type/RING-type Zinc finger protein and Y2H320/TGA9, a bZIP transcription factor family protein interacted with MYB26 in plant cell nuclei. Y2H320/TGA9 has been shown to be functionally redundant with TGA10 in regulating anther development (Murmu et al. 2010). The tga9tga10 double mutant produced indehiscent anthers and was male sterile due to the developmental arrest of the adaxial anther lobes and abnormal tapetum and pollen development in the abaxial anther lobes. In summary, MYB26 appears to regulate endothecium development and secondary thickening formation and thus anther dehiscence probably through directly regulating the subfamily VII RLCK PKSP and the NAC transcription factors NST1, NST2 and by interacting with a CHY-type/RING-type Zinc finger protein Y2H560 and the bZIP transcription factor Y2H320/TGA9.
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Tang, Lee-kwan y 鄧利軍. "Functional characterization of an Arabidopsis anther-specific gene encoding a dihydrolavonol 4-reductase-like protein". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2009. http://hub.hku.hk/bib/B41633891.
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Dill, Patrick W. "From Ritual to Art in the Puritan Music of Colonial New England: the Anthems of William Billings". Thesis, University of North Texas, 2012. https://digital.library.unt.edu/ark:/67531/metadc149583/.
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The manner in which Billings’s music contrasts with the Puritan musical ideal clearly demonstrates his role in the transition from ritual to art in the music of eighteenth-century New England. The tenets of Puritan worship included the restriction that music should serve primarily as a form of communal prayer for the congregation and in a secondary capacity to assist in biblical instruction. Billings’s stylistic independence from Puritan orthodoxy began with a differing ideology concerning the purpose of music: whereas Calvin believed music merely provided a means for the communal deliverance of biblical text, Billings recognized music for its inherent aesthetic worth. Billings’s shift away from the Puritan musical heritage occurred simultaneously with considerable change in New England in the last three decades of the eighteenth century. A number of Billings’s works depict the events of the Revolutionary War, frequently adapting scriptural texts for nationalistic purposes. The composition of occasional works to commemorate religious and civic events reflects both the increase in society’s approval of choral music beyond its nominal use in worship, both in singing schools and in choirs. With his newfound independence from Puritan ritual, Billings seems to have declared himself one of the United States of America’s first musical artists.
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Ullén, Henning. "I Worship Your Anthem". Thesis, Kungl. Musikhögskolan, Institutionen för jazz, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kmh:diva-2078.
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Jenkins, R. E. "Developmental studies in relation to anther culture in Hordeum vulgare". Thesis, University of East Anglia, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.374688.
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Day, A. "The chloroplast genome in albino plants produced by anther culture". Thesis, University of East Anglia, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.304052.
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Thompson, Deborah M. "Development and utilization on anther culture technology in barley improvement". Thesis, University of Reading, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.303872.
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Dunford, Roy Patrick. "Molecular aspects of albinism in anther culture derived barley plants". Thesis, University of Leicester, 1989. http://hdl.handle.net/2381/34406.
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Haploid cereal plants can be regenerated from single pollen grains via the process of anther culture. Anther culture of cereals is of potential use in crop improvement programmes. One problem associated with anther culture of cereal plants is a high incidence of albino individuals which cannot be used in crop breeding schemes. Albinos derived from barley anther culture (albino pollen plants) are severely pigment deficient and from electron microscopy studies appear to possess plastids that are developmentally arrested at a stage prior to the differentiation of proplastids to mature chloroplasts. The aim of the project has been to investigate some of the molecular aspects of albinism in these individuals. In vitro propagation experiments were carried out to find the conditions necessary to improve the growth and maintenance of albino pollen plants with the objective of producing a continuous supply of albino tissue for molecular analysis. However, use of various media containing organic and inorganic supplements including a number of plant growth regulators failed to improve the growth of albino plants. Southern analysis revealed that four out of the five albino plants studied exhibit ptDNA restriction patterns that are different to that expected from the wild type map of the barley plastid genome due to the alteration or deletion of specific ptDNA fragments. One plant appears to contain a major form of ptDNA that has undergone a deletion event removing 75% of all sequences. This confirms that the albino pollen plants examined in this study contain forms of the plastid genome that have undergone structural alteration. I have termed these variant plastid genomes ptDNAs. Most of the albino plants studied appear to contain heterogenous populations of ptDNAs. One albino barley pollen plant appears to possess an intact plastid genome. For all the albinos studied the overall levels of ptDNA are reduced 5-15 fold compared to the levels found in normal green tissues. Northern analyses revealed that the transcripts from the ptDNA genes rbcL and psbD-psbC do not accumulate or are present in albino tissues at 5-10% the level found in seed-derived green shoots. Levels of the plastid encoded 16S and 23S rRNAs are similarly reduced in albino tissues. Further Northern analysis revealed that the abundance of transcripts from the nuclear genes rbcS and cab are present in most albino plants at 10% the level found in normal green tissues. Southern analysis indicated that the nuclear DNA restriction fragments encompassing the cab and rbcS genes in two albino plants had not been altered or deleted during the anther culture process. Analysis of green pollen plants indicated that they contain ptDNA of apparently normal structure and abundance and accumulate transcripts from plastid genes and nuclear genes encoding chloroplast polypeptides to the same levels found in the leaves of light grown seedlings. These results represent the first determination of the levels of photosynthetic gene expression in both albino and green pollen plants.
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Iler, Devin. "Formal Devices of Trance and House Music: Breakdowns, Buildups, and Anthems". Thesis, University of North Texas, 2011. https://digital.library.unt.edu/ark:/67531/metadc103332/.
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Trance and house music are sub-genres within the genre of electronic dance music. The form of breakdown, buildup and anthem is the main driving force behind trance and house music. This thesis analyzes transcriptions from 22 trance and house songs in order to establish and define new terminology for formal devices used within the breakdown, buildup and anthem sections of the music.
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Lai, Kwok-wai y 賴國偉. "Proteome analysis of anther-development-related proteins in a thermo-sensitive male sterile rice mutant". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2003. http://hub.hku.hk/bib/B29517862.
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Cutright, Rebecca J. "Derivation and Comparison of Androgenic and Gynogenic Monoploid Potato Families". Thesis, Virginia Tech, 1998. http://hdl.handle.net/10919/37017.
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Monopoloid potato (2n = 1x = 12) can be derived either paternally through anther/microspore culture or maternally through crossing with a haploid-inducing pollinator. Evidence from other genera suggests that androgenic and gynogenic haploid populations derived from the same parent may differ due to gametic selection and/or epigenetic factors. Our objectives were to derive androgenic and gynogenic monoploid populations from each of two diploid (2n = 2x = 24) Solanum phureja clones and compare their phenotypic characteristics in a greenhouse study. A haploid-inducing pollinator, S. phureja IVP101, was crossed to two selections of S. phureja (PP5 and BARD1-3). A total of 185 fruit was obtained from PP5 and 398 from BARD1-3, resulting from 85% and 65% fruit set, respectively. Seed lacking the dominant embryo spot marker carried by IVP101 were selected and germinated in vitro. From 29,300 PP5 x IVP101 seeds, 278 were spotless, resulting in 27 monoploids. Approximately 37 monoploids were obtained from the 99,500 BARD1-3 x IVP101 seeds of which 500 were spotless. In anther culture, PP5 and BARD1-3 yielded 0.16 and 1.67 embryos per anther respectively of which 51% and 44% of the regenerants were monoploid. A total of 32 anther-derived monoploids has been obtained from PP5 and 130 from BARD1-3. Rooted cuttings of 21 androgenic and 21 gynogenic PP5 monoploids were established in a greenhouse in each of three randomized complete blocks. Although the anther-derived monoploids appeared more vigorous, none of the differences between the two populations were significant. Flow cytometry revealed that anther derived progeny of PP5 and BARD1-3 had 3-8% greater nuclear DNA content than gynogenic monoploids derived from the same parental clones.Master of Science
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Curran, Helen R. (Helen Rae). "Thecaphora anther-smut fungi : ecology and implications for CFR Oxalis species". Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/20293.
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Thesis (MSc)--Stellenbosch University, 2012.ENGLISH ABSTRACT: Only a limited number of systems involving anther-smut fungi have been studied, usually due to the economic significance of their crop plant hosts. A smut fungus of the genus Thecaphora has been discovered infecting Oxalis hosts in South Africa. This pathogenic fungus, Thecaphora capensis, produces dark-coloured spores in the anthers of host flowers, rendering it an anther-smut fungus. The host genus is the seventh largest plant genus in the Cape Floristic Region (CFR) and the largest geophytic genus of this region. Nine Oxalis species that host T. capensis have been identified across a wide distribution in the CFR of South Africa. A preliminary assessment of T. capensis infections of Oxalis was conducted in 2009, which provided a foundation for further research into the ecological and evolutionary consequences of hosting this fungus. In this study, a comprehensive host diversity assessment was conducted to determine the extent of infected Oxalis individuals within the CFR. Three new Oxalis host species for Thecaphora capensis were discovered. This brings the total number of known hosts to twelve. The morphological and reproductive effects of the fungus were assessed on two host species (O. incarnata and O. lanata) by comparing healthy and infected individuals of these species. Infection by Thecaphora capensis had a significantly negative effect on both of these factors. Host resources appear to be co-opted for fungal spore production, since floral morphological characters of infected individuals were reduced in size. Furthermore, infection by T. capensis ensured near-universal sterility in both hosts. Differences in floral characters and pollinator preferences for healthy Oxalis incarnata and O. lanata individuals from disease-free and diseased populations were compared to determine the evolutionary influence of Thecaphora capensis infections. It was shown that this pathogen can have a significant evolutionary influence on its hosts, showing its ability to shape flower size and pollinator activity in O. lanata, but not in O. incarnata. A need has therefore been identified to assess these evolutionary forces independently for each host and its pathogen before making erroneous assumptions for conservation practices. Plant pollinators play an integral role in plant fitness. Pollinator movements within a population are important when between-flower spore transfer by pollinators increases the likelihood of new infections. Pollinator movements may be influenced by host density and the frequency of diseased individuals, amongst other factors. Pollinators were found to mediate Thecaphora capensis spore transfers within diseased Oxalis populations. Host density and disease frequency affected the number of spores transferred under field and standardized conditions. More research is required to investigate confounding factors in these complex systems. This study highlighted the complexities of a fungal-plant-insect relationship, the evolutionary consequences of such fungal infections and the various factors influencing the likelihood of new infections. This research adds to the limited body of knowledge on multi-organismal interactions in the CFR and provides a base for more detailed future studies on this intriguing system.
AFRIKAANSE OPSOMMING: 'n Brandswam, wat deel is van die Thecaphora genus,is ontdek in 'n Oxalis blom waar dit die gasheer plant se blom gebruik om spore in te produseer. Die swam, Thecaphora capensis, produseer donker gekleurde spore in die helmknoppe van die blomme van gasheer plante, daarom word dit geklasifiseer as 'n brandswam van die helmknop. Die gasheer plante van die swam is deel van die genus Oxalis, die sewende grootste plant genus in die Kaapse Floristiese Streek (KFS) en die grootste geofitiese genus in die streek. Nege Oxalis species is al klaar identifiseer as gasheer plante van T. capensis. Hulle is versprei oor 'n groot area van die KFS van Suid Afrika. 'n Primêre ondersoek van T. capensis infeksies op Oxalis is in 2009 onderneem. Hierdie ondersoek het gelei tot meer vrae oor die sisteem en het 'n goeie fondasie geskep vir verdere navorsing rakende die ekologiese koste verbonde daaraan om as gasheer plant vir 'n swam op te tree. 'n Deeglike ondersoek is in die KFS aangepak om die Oxalis gasheer plante van die brand swam te identifiseer en om voort te bou op die basiskennis wat in die primêre ondersoek daargestel is. Drie nuwe Oxalis gasheer plante van Thecaphora capensis is ontdek. Die totale aantal gasheer plante staan nou op twaalf. Gesonde en geinfekteerde individuele gasheer plante is gebruik om die morfologiese en reproduktiewe effekte van die swam te toets in twee Oxalis spesies (O. incarnata en O. lanata). Die negatiewe gevolge om 'n gasheer plant van die brand swam te wees was duidelik toe gesonde en geinfekteerde individuele met mekaar vergelyk is. Dit kom voor asof gasheer plante se hulpbronne vir spoor produksie gebruik word, want hulle is morfologies kleiner en meestal steriel. Die evolusionêre effek van Thecaphora capensis op 'n populasie is getoets met gesonde individuele in populasies van twee Oxalis spesies. Blomkenmerke en insek bestuiwers van gesonde individue in gesonde en geinfekteerde populasies is ondersoek om die effekte van T. capensis op populasies te toets. Daar is suksesvol gedemonstreer dat swamme sterk evolusionêre kragte uitoefen, en die vermoë het om plantpopulasies te vorm en te verander, ofskoon nie in alle gevalle ewe sterk nie. Daarom is dit belangrik om die evolusionêre kragte vir elke gasheer plant en sy patogeen onafhanklik te assesseer, sonder om algemene aannames te maak in bewaringspraktyke. Plantbestuiwers speel 'n belangrike rol in die fiksheid van plante. Hulle kan hul fiksheid verbeter deur bestuiwers te lok met blomme en deur aspekte geassosieer met blomme. Die bewegingspatrone van plantbestuiwers is baie belangrik indien hulle helmknop-geproduseerde spore van brandswamme vervoer instede van stuifmeel, want dit vergroot die kanse vir nuwe infeksies. Die bewegingspatrone van plantbestuiwers word, onder andere, beinvloed deur die digtheid en frekwensie van geinfekteerde individue. Plantbestuiwers speel 'n belangrike rol in die vervoer van Thecaphora capensis spore in geinfekteerde Oxalis populasies. Die digtheid en frekwensie van geinfekteerde blomme het die vervoer van spore geaffekteer onder veld en gestandardiseerde kondisies, alhoewel baie veranderlikes so 'n komplekse natuurlike sisteem beinvloed. Hierdie studie beklemtoon die kompleksiteit van 'n fungus-plant-insek verhouding, die gevolge van so 'n interaksie en die verskeie faktore wat die waarskynlikheid van nuwe infeksies beinvloed. Tot dusver is daar 'n beperkte aantal sisteme soos hierdie bestudeer waarin 'n brandswam van die helmknop betrokke is, en die enkele beskikbare studies is onderneem meestal as gevolg van hulle ekonomiese effekte op landboukundig belangrike gasheer plante. Hierdie studie verteenwoordig 'n belangrike byvoeging tot die inter-organismiese studies in die KFS. 'n Holistiese ekologiese oorsig soos hierdie verskaf 'n belangrike basis vir toekomstige studies en bewarings- en bestuurspraktyke.
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Finnie, Susan Jane. "The development and utilisation of anther culture technology in barley breeding". Thesis, University of Edinburgh, 1990. http://hdl.handle.net/1842/14853.
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In this thesis, the potential of barley anther culture as a method for the rapid and efficient production of homozygous lines has been investigated. The substitution of sucrose by maltose in the anther culture medium led to a substantial improvement in the frequency of green plant regeneration. High concentrations (6-12%) of maltose gave greater number of green plants than low (1-3%) concentrations. In addition, plant regeneration was predominantly via an embryogenic route rather than an intermediate callus phase. Three commercially important spring barley cultivars, Tweed, Tyne and Natasha were considered. All three responded on a maltose-based medium, although to differing extents. The genetic stability of anther culture-derived lines produced by this method was assessed by karyotype analysis, and by using a range of biochemical and molecular markers. Low levels of variation were detected and the relative stability of the system may be attributed to the embryogenic mode of regeneration attained on a medium containing maltose. Despite the improvements obtained using the maltose protocol, response to anther culture was shown to be largely dependent on genotype. An investigation of the transmission of anther culture responsiveness into F1 hybrids produced from H.vulgare x H.spontaneum crosses showed that responsiveness was dominant to non-responsiveness. A high degree of heterosis for anther culture response was also observed in F1 progenies. An investigation of anther culture response in the wheat/barley disomic chromosome addition lines showed that addition of a single pair of barley chromosomes could not positively modify anther culture response in an unresponsive wheat background. The implications of these results are discussed in relation to the application of anther culture technology to barley breeding and genetics.
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Foroutan-Pour, Kayhan. "Aspects of barley post-anthesis nitrogen physiology". Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=22730.
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The protein concentration of cereal grains is low and the production of cereal crops with increased grain protein concentrations is desirable. This work investigates the physiological aspects of protein accumulation potential in barley grain. A recently developed perfusion system was used in four experiments conducted in 1993 and 1994. In the field experiment, plants were allowed to take up urea at 15 or 30 mM N, or ethephon at 15 $ mu$ M. Abscisic acid and 2,4-D decreased total seed weight spike$ sp{-1}$. Gibberellic acid and 2,4-D increased seed protein concentration and content, while ABA decreased both of these. Kinetin and abscisic acid treatments resulted in the highest and lowest levels, respectively for flag leaf photosynthesis, stomatal conductance, transpiration and intercellular CO$ sb2$ concentration. Both protein content spike$ sp{-1}$ and seed protein concentration were elevated in plants fertilized with 10.7 mM N via the soil and plants perfused with 30 mM N via the peduncle. Plants receiving treatments of 10.7 mM N from the soil and mixture of 30 mM N and GA$ sb3$ or 2,4-D through the peduncle had increased protein content seed$ sp{-1}$, and the highest seed weight spike$ sp{-1}$, respectively. Peduncle perfusion with 30 mM N increased spike protein concentration and content and grain protein concentration without affecting seed weight spike$ sp{-1}$. Grain protein concentration was increased by peduncle perfusion with ethephon. The perfusion technique worked well under field conditions. (Abstract shortened by UMI.)
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Fandrich, David John. "The birthing process select anthems of Samuel Sebastian Wesley and the nineteenth-century English musical renaissance /". 24-page ProQuest preview, 2008. http://proquest.umi.com/pqdweb?did=1507552661&sid=1&Fmt=2&clientId=10355&RQT=309&VName=PQD.
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Shawn, Terry Alexander Lee. "A Conductor's Guide To Performance Issues Arising From The Use Of Eighteenth-Century Pitch Levels In The Performance Of Handel's Four Coronation Anthems". Diss., The University of Arizona, 2008. http://hdl.handle.net/10150/194723.
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In this study I attempted to create a historically informed performance of Handel's Four Coronation Anthems at the pitch of a1 = 423, without the benefit of baroque instruments. The issue of lowering the performance pitch from a1 = 440 to a1 = 423 had varying effects on the singers and instrumentalists. Replicating the baroque sound required some modifications to modern instruments and some mental and vocal adjustments for the singers. Several singers experienced vocal relief due to the lowered pitch, while some instrumentalists were faced with re-adjusting their technique to compensate for the modifications made to their instruments. The modifications ranged from exchanging the violin and viola strings from steel to gut to lengthening the oboe reeds and the bassoon's bocal enough to effectively lower the pitch almost a half step, or .17 Hertz (Hz.). Through the aid of audio and visual recordings of the performance and the performer's questionnaires, several discoveries were made about creating a historically informed performance. Primarily, when changing the pitch of a composition, it is better to adjust the pitch in half steps rather than quarter-tone increments. It was further revealed when changing the pitch that some singers experienced difficulty maintaining pitch due to their vocal muscle memory, whereas, some instrumentalists possess varying degrees of individual pitch memory and perception. In order to deal effectively with the issue of maintaining pitch, it was revealed that it is important to have more rehearsal time at the adjusted pitch. With respect to the modifications made to the instruments, it is vital to the success of the performance to allow the players enough time with modified instruments to be able to maintain consistent tuning within the instrument. The musician's individual pitch perception and preference have an affect on the performance, and the conductor would be well advised to refer to the discoveries presented in this document. This study was successful in discovering ways to present a historically informed performance at a pitch other than a1 = 440 and several suggestions for creating further historically informed performances were explored.
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Song, Jie. "MYB26 controls arabidopsis anther dehiscence by regulating secondary thickening in the endothecium". Thesis, University of Nottingham, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.523648.
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