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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

The regulation of flower development in indeterminate Impatiens balsamina L

Greville, Karen January 2001 (has links)
No description available.
2

Self-incompatibility of olive.

Seifi, Esmaeil January 2008 (has links)
The olive (Olea europaea L.) is one of the most ancient fruit trees and has been cultivated for its oil in the Mediterranean area for thousands of years. Today, the consumption of olive oil and table olives is increasing both in traditional producing countries and the entire world. Most olive cultivars are self-incompatible and do not produce a commercial yield after self pollination. In this thesis, inflorescence architecture and sexual compatibility relationships of some olive cultivars, and gene expression in olive pistils during flowering were studied. To study the inflorescence architecture of olive, 45 inflorescences in each of the cultivars Manzanillo, Mission, and Frantoio were checked every morning from flower opening to petal fall. The flower position on the inflorescence had a highly significant effect on the opening day in all cultivars. Terminal flowers and the flowers located on the primary branches opened earlier than flowers located on the secondary branches. Flower position also had a highly significant effect on gender in Manzanillo and Mission. In Manzanillo, the secondary branches had fewer perfect flowers than the primary branches. In Mission, the secondary branches had no perfect flowers at all. In Manzanillo, perfect flowers had significantly longer petal persistence than staminate flowers. To study flower competition within the inflorescence, the distal halves, on which the flowers tend to be perfect, of 120 inflorescences in three trees of Manzanillo were removed about one month before full bloom. This resulted in a highly significant increase in the percentage of perfect flowers on the proximal halves. The effects of shoot orientation and inflorescence location on inflorescence characteristics in the cultivars Frantoio, Kalamata, and Koroneiki were also studied. For each cultivar, inflorescence characteristics in three sections of shoots (top, middle, and base) and four sides of the three selected trees (north, south, east, and west) were recorded. The statistical analysis showed that basal inflorescences were shorter and with fewer flowers but with the same percentage of perfect flowers. Shoot orientation did not have any influence on these characteristics in any of the cultivars. Sexual compatibility was assessed using two methods. In the first method, controlled crossings were performed in the cultivars Frantoio, Koroneiki, and Kalamata. The pistils were harvested one week after hand pollination and stained with 0.1% aniline blue. The styles and ovules were separated, mounted in 80% glycerol, and observed under a fluorescence microscope. In Frantoio and Koroneiki, the number of ovules penetrated by a pollen tube was used to estimate the level of sexual compatibility. In Kalamata, the numbers of ovules penetrated by pollen tubes were not significantly different between treatments; therefore, the number of pollen tubes in the lower style was used. All the cultivars studied were self- incompatible. Frantoio (as a host) was incompatible with Koroneiki and Barnea but partially compatible with Mission. Koroneiki (as a host) was incompatible with Barnea but partially compatible with Frantoio and Mission. Kalamata (as a host) was compatible with Barnea, incompatible with Mission and Koroneiki in 2004, but partially compatible with them in 2005. In the second method, eight microsatellite markers were used for genotyping three Kalamata mother trees, 40 embryos per mother tree, and all the potential pollen donors. Genotyping data were analysed using FaMoz software, and the number of embryos assigned to each putative pollen donor was determined. Paternity analysis showed that Kalamata (as a host) was self-incompatible, compatible with Barnea, Benito, and Katsourela, but incompatible with Arbequina, Azapa, and Picual. To study the gene expression in olive pistils during flowering, a genomic approach was initiated using cDNA subtractive array analysis. Total RNA was isolated from olive pistils at two developmental stages, where self-incompatibility (SI) genes are expected to be differentially expressed: 1) small green flower buds (expression of SI genes not expected) and 2) large white flower buds containing receptive pistils just prior to opening (expression of SI genes expected). From each stage, cDNA libraries were prepared and put through forward and reverse subtractive hybridisations to enrich for differentially expressed cDNAs in stage 2. Macroarrays were prepared by printing 2304 differentially expressed cDNAs onto nylon membranes and hybridised with forwardand reverse-subtracted probes. The analysis identified 90 up-regulated cDNA clones highly expressed in receptive pistils. Further subtracted and unsubtracted hybridisations confirmed up-regulation of the majority of these cDNAs. Gene expression profiles across different tissues showed that most of the genes were pistil-specific. The expression pattern of the genes showed high similarity in Kalamata, Frantoio, Barnea, and Pendolino. All the screened genes were sequenced and their similarities were searched in the NCBI database. The most redundant and interesting up-regulated clones were those similar to a receptor protein kinase-like protein. Some versions of this protein play a role in the sporophytic SI system of Brassica and the gametophytic SI system of Papaver and rye. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1325369 / Thesis (Ph.D.) -- University of Adelaide, School of Agriculture, Food and Wine, 2008
3

Self-incompatibility of olive.

Seifi, Esmaeil January 2008 (has links)
The olive (Olea europaea L.) is one of the most ancient fruit trees and has been cultivated for its oil in the Mediterranean area for thousands of years. Today, the consumption of olive oil and table olives is increasing both in traditional producing countries and the entire world. Most olive cultivars are self-incompatible and do not produce a commercial yield after self pollination. In this thesis, inflorescence architecture and sexual compatibility relationships of some olive cultivars, and gene expression in olive pistils during flowering were studied. To study the inflorescence architecture of olive, 45 inflorescences in each of the cultivars Manzanillo, Mission, and Frantoio were checked every morning from flower opening to petal fall. The flower position on the inflorescence had a highly significant effect on the opening day in all cultivars. Terminal flowers and the flowers located on the primary branches opened earlier than flowers located on the secondary branches. Flower position also had a highly significant effect on gender in Manzanillo and Mission. In Manzanillo, the secondary branches had fewer perfect flowers than the primary branches. In Mission, the secondary branches had no perfect flowers at all. In Manzanillo, perfect flowers had significantly longer petal persistence than staminate flowers. To study flower competition within the inflorescence, the distal halves, on which the flowers tend to be perfect, of 120 inflorescences in three trees of Manzanillo were removed about one month before full bloom. This resulted in a highly significant increase in the percentage of perfect flowers on the proximal halves. The effects of shoot orientation and inflorescence location on inflorescence characteristics in the cultivars Frantoio, Kalamata, and Koroneiki were also studied. For each cultivar, inflorescence characteristics in three sections of shoots (top, middle, and base) and four sides of the three selected trees (north, south, east, and west) were recorded. The statistical analysis showed that basal inflorescences were shorter and with fewer flowers but with the same percentage of perfect flowers. Shoot orientation did not have any influence on these characteristics in any of the cultivars. Sexual compatibility was assessed using two methods. In the first method, controlled crossings were performed in the cultivars Frantoio, Koroneiki, and Kalamata. The pistils were harvested one week after hand pollination and stained with 0.1% aniline blue. The styles and ovules were separated, mounted in 80% glycerol, and observed under a fluorescence microscope. In Frantoio and Koroneiki, the number of ovules penetrated by a pollen tube was used to estimate the level of sexual compatibility. In Kalamata, the numbers of ovules penetrated by pollen tubes were not significantly different between treatments; therefore, the number of pollen tubes in the lower style was used. All the cultivars studied were self- incompatible. Frantoio (as a host) was incompatible with Koroneiki and Barnea but partially compatible with Mission. Koroneiki (as a host) was incompatible with Barnea but partially compatible with Frantoio and Mission. Kalamata (as a host) was compatible with Barnea, incompatible with Mission and Koroneiki in 2004, but partially compatible with them in 2005. In the second method, eight microsatellite markers were used for genotyping three Kalamata mother trees, 40 embryos per mother tree, and all the potential pollen donors. Genotyping data were analysed using FaMoz software, and the number of embryos assigned to each putative pollen donor was determined. Paternity analysis showed that Kalamata (as a host) was self-incompatible, compatible with Barnea, Benito, and Katsourela, but incompatible with Arbequina, Azapa, and Picual. To study the gene expression in olive pistils during flowering, a genomic approach was initiated using cDNA subtractive array analysis. Total RNA was isolated from olive pistils at two developmental stages, where self-incompatibility (SI) genes are expected to be differentially expressed: 1) small green flower buds (expression of SI genes not expected) and 2) large white flower buds containing receptive pistils just prior to opening (expression of SI genes expected). From each stage, cDNA libraries were prepared and put through forward and reverse subtractive hybridisations to enrich for differentially expressed cDNAs in stage 2. Macroarrays were prepared by printing 2304 differentially expressed cDNAs onto nylon membranes and hybridised with forwardand reverse-subtracted probes. The analysis identified 90 up-regulated cDNA clones highly expressed in receptive pistils. Further subtracted and unsubtracted hybridisations confirmed up-regulation of the majority of these cDNAs. Gene expression profiles across different tissues showed that most of the genes were pistil-specific. The expression pattern of the genes showed high similarity in Kalamata, Frantoio, Barnea, and Pendolino. All the screened genes were sequenced and their similarities were searched in the NCBI database. The most redundant and interesting up-regulated clones were those similar to a receptor protein kinase-like protein. Some versions of this protein play a role in the sporophytic SI system of Brassica and the gametophytic SI system of Papaver and rye. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1325369 / Thesis (Ph.D.) -- University of Adelaide, School of Agriculture, Food and Wine, 2008
4

MtSUPERMAN controls the number of flowers per inflorescence and floral organs in the inner three whorls of Medicago truncatula

Rodas Méndez, Ana Lucía 02 September 2021 (has links)
[ES] Las leguminosas son un grupo de plantas consideradas de gran importancia por su valor nutricional para la alimentación humana y ganadera. Además, las familias de leguminosas se caracterizan por rasgos distintivos de desarrollo como su inflorescencia compuesta y su compleja ontogenia floral. Para comprender mejor estas características distintivas, es importante estudiar los genes reguladores clave involucrados en el desarrollo de la inflorescencia y la flor. El gen SUPERMAN (SUP) es un factor transcripcional de dedos de zinc (Cys2-Hys2) considerado como un represor activo que controla el número de estambres y carpelos en A. thaliana. Además, SUP está involucrado en la terminación del meristemo floral y el desarrollo de los tejidos derivados del carpelo. El objetivo principal de este trabajo fue la caracterización funcional del ortólogo de SUP en la leguminosa modelo Medicago truncatula (MtSUP). Logramos este objetivo en base a un enfoque de genética reversa, análisis de expresión génica y ensayos de complementación y sobreexpresión. Nuestros resultados muestran que MtSUP es el gen ortólogo de SUP en M. truncatula. MtSUP comparte algunos de los roles ya descritos para SUP con algunas variaciones. Curiosamente, MtSUP controla la determinación del meristemo inflorescente secundario (I2) y de los primordios comunes (CP) a pétalos y estambres. Por tanto, MtSUP controla el número de flores y de pétalos-estambres que producen el meristemo I2 y los primordios comunes, respectivamente. MtSUP muestra funciones novedosas para un gen de tipo SUP, desempeñando papeles clave en los meristemos que confieren complejidad de desarrollo a esta familia de angiospermas. Este trabajo permitió identificar a MtSUP, un gen clave que forma parte de la red reguladora genética que subyace al desarrollo de la inflorescencia compuesta y de las flores en la leguminosa modelo M. truncatula. / [CA] Les lleguminoses són un gran grup de plantes considerades de gran importància pel seu valor nutricional per a l'alimentació humana i ramadera. A més, les famílies de lleguminoses es caracteritzen per trets distintius de desenrotllament com la seua inflorescència composta i la seua complexa ontogènia floral. Per a comprendre millor estes característiques distintives, és important estudiar els gens reguladors clau involucrats en la inflorescència i el desenrotllament floral. El gen SUPERMAN (SUP) és un factor transcripcional de dits de zinc (Cys2-Hys2) considerat com un repressor actiu que controla el nombre d'estams i carpels en A. thaliana. A més, SUP està involucrat en la terminació del meristemo floral i el desenrotllament dels teixits derivats del carpel. "L'objectiu principal d'este treball va ser la caracterització funcional de l'ortòleg de SUP en la lleguminosa model Medicago truncatula (MtSUP) . Aconseguim l'objectiu amb base en un enfocament genètic invers, anàlisi d'expressió gènica i assajos de complementació i sobreexpressió. Els nostres resultats mostren que MtSUP és el gen ortòleg de SUP en M. truncatula. MtSUP compartix alguns dels rols ja descrits per a SUP amb variacions. Curiosament, MtSUP està involucrat en la determinació del meristemo de la inflorescència secundària (I2) i els primordios comuns (CP). Per tant, MtSUP controla el nombre de flors i pètals-estams que produïxen el meristemo I2 i els primordios comuns, respectivament. MtSUP mostra funcions noves per a un gen tipus SUP, exercint papers clau en els meristemos que conferixen complexitat de desenrotllament a esta família d'angiospermes. "Este treball va permetre identificar a MtSUP, un gen clau que forma part de la xarxa reguladora genètica darrere de la inflorescència composta i el desenrotllament de flors en la lleguminosa model M. truncatula. / [EN] Legumes are a large group of plants considered of great importance for their nutritional value in human and livestock nutrition. Besides, legume families are characterized by distinctive developmental traits as their compound inflorescence and complex floral ontogeny. For a better understanding of these distinctive features is important to study key regulatory genes involved in the inflorescence and floral development. The SUPERMAN (SUP) gene is a zinc-finger (Cys2-Hys2) transcriptional factor considered to be an active repressor that controls the number of stamens and carpels in A. thaliana. Moreover, SUP is involved in the floral meristem termination and the development of the carpel marginal derived tissues. The main objective of this work was the functional characterization of the SUP orthologue in the model legume Medicago truncatula (MtSUP). We achieved this objective based on a reverse genetic approach, gene expression analysis, and complementation and overexpression assays. Our results show that MtSUP is the orthologous gene of SUP in M. truncatula. MtSUP shares some of the roles already described for SUP with variations. Interestingly, MtSUP controls the determinacy of the secondary inflorescence (I2) meristem and the common primordia (CP). Thus, MtSUP controls the number of flowers and petal-stamens produced by the I2 meristem and the common primordia respectively. MtSUP displays novel functions for a SUP-like gene, playing key roles in the meristems that confer developmental complexity to this angiosperm family. This work allowed to identify MtSUP, a key gene that participates in the genetic regulatory network underlying compound inflorescence and flower development in the model legume M. truncatula. / I would like to thanks the Spanish Ministry of Economy and Competitiveness for the grant (MINECO; BIO2016-75485-R) that supported this work. Special thanks to the Generalitat Valenciana for funding my doctorate with the Santiago Grisolía predoctoral scholarships / Rodas Méndez, AL. (2021). MtSUPERMAN controls the number of flowers per inflorescence and floral organs in the inner three whorls of Medicago truncatula [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/171474 / TESIS
5

New Insights into Pea Compound Inflorescence Development: Role of FTc and VEGETATIVE1 as Regulatory Factors

Serra Picó, Marcos Pascual 28 January 2024 (has links)
[ES] La arquitectura de la inflorescencia determina la posición y el número de flores (y frutos) en la planta. Esto afecta a la forma de la planta, lo que contribuye a la diversidad morfológica e influye en la producción de semillas. Por lo tanto, comprender cómo funciona la genética que está detrás del desarrollo de la inflorescencia es relevante no solo para saber más sobre la biología del desarrollo de las plantas, sino también para la agricultura, con el fin de diseñar nuevas estrategias para la mejora de plantas. La mayoría de las leguminosas tienen inflorescencias compuestas, en las que las flores no se forman en el tallo principal sino a partir de inflorescencias secundarias (I2) en los flancos de la inflorescencia primaria o principal (I1). Esto contrasta con las plantas con inflorescencias simples, como Arabidopsis, donde las flores se forman directamente a partir del I1. El guisante (Pisum sativum) pertenece a la familia de las Fabaceae y al clado galegoide de las leguminosas y tiene una inflorescencia compuesta. Es bien sabido que VEGETATIVE1/ FULc (VEG1) codifica un factor de transcripción que especifica la identidad del meristemo I2 en leguminosas, pero aún se desconoce cómo y a través de qué genes VEG1 controla el desarrollo del I2 y las vías genéticas en las que está involucrado. En este trabajo, nuestro objetivo fue identificar las dianas regulatorias de VEG1. Para ello, comparamos los transcriptomas provenientes de ápices de inflorescencia del control silvestre (wild-type) con los de mutantes de guisante con defectos en el desarrollo de la inflorescencia: proliferating inflorescence meristems (pim - con múltiples meristemos I2), veg1 y vegetative2 (veg2 - ninguno de los cuales produce ni meristemos I2 ni flores). Usando este enfoque, hemos aislado algunos genes que se expresan en el I2 e identificado algunas posibles dianas de VEG1, entre ellas algunos genes que parecen prometedores para ser usados a modo de herramientas genéticas para la mejora del rendimiento en la producción en leguminosas. FLOWERING LOCUS T (FT) es un regulador clave en la red genética del fotoperíodo que controla el tiempo de floración en Arabidopsis. En leguminosas, el clado FT se ha diversificado en tres subclados: FTa, FTb y FTc. En guisante,el gen FTc se encuentra distante filogenéticamente de los otros genes FT y tiene un patrón de expresión inusual, ya que solo se expresa en el ápice de la inflorescencia. En este trabajo hemos caracterizado mutantes ftc de guisante y los hemos utilizado para analizar las interacciones genéticas de FTc con DETERMINATE y LATE FLOWERING, que son los homólogos en guisante de TERMINAL FLOWER 1 de Arabidopsis. Este análisis ha revelado una función de FTc en el control de la floración y, curiosamente, también en el desarrollo del meristemo I2, estando esta segunda función posiblemente mediada por la regulación de FTc en la expresión de VEG1. / [CA] L'arquitectura de la inflorescència determina la posició i el nombre de flors (i fruits) en la planta. Això afecta a la forma de la planta, la qual cosa contribueix a la diversitat morfològica i influeix en la producció de llavors. Per tant, comprendre com funciona la genètica que està darrere del desenvolupament de la inflorescència és rellevant no sols per a saber més sobre la biologia del desenvolupament de les plantes, sinó també per a l'agricultura, amb la finalitat de dissenyar noves estratègies per a la millora de plantes. La majoria de les lleguminoses tenen inflorescències compostes, en les quals les flors no es formen en la tija principal sinó a partir d'inflorescències secundàries (I2) en els flancs de la inflorescència primària o principal (I1). Això contrasta amb les plantes amb inflorescències simples, com Arabidopsis, on les flors es formen directament a partir de l'I1. El pésol (Pisum sativum) pertany a la família de les Fabaceae i al clade galegoide de les lleguminoses i té una inflorescència composta. És ben sabut que VEGETATIVE1/ FULc (VEG1) codifica un factor de transcripció que especifica la identitat del meristemo I2 en lleguminoses, però encara es desconeix com i a través de quins gens VEG1 controla el desenvolupament de l'I2 i les vies genètiques en les quals està involucrat. En aquest treball, el nostre objectiu va ser identificar les dianes reguladores de VEG1. Per a això, comparem els transcriptomas provinents d'àpexs d'inflorescència del control silvestre (wild-type) amb els de mutants de pésol amb defectes en el desenvolupament de la inflorescència: proliferating inflorescence meristems (pim - amb múltiples meristemos I2), veg1 i vegetative2 (veg2 - cap dels quals produeix ni meristemos I2 ni flors). Usant aquest enfocament, hem aïllat alguns gens que s'expressen en l'I2 i identificat algunes possibles dianes de VEG1, entre elles alguns gens que semblen prometedors per a ser usats a manera d'eines genètiques per a la millora del rendiment en la producció en lleguminoses. FLOWERING LOCUS T (FT) és un regulador clau en la xarxa genètica del fotoperíode que controla el temps de floració en Arabidopsis. En lleguminoses, el clade FT s'ha diversificat en tres subclades: FTa, FTb i FTc. En pésol, el gen FTc es troba distant filogenéticamente dels altres gens FT i té un patró d'expressió inusual, ja que només s'expressa en l'àpex de la inflorescència. En aquest treball hem caracteritzat mutants ftc de pésol i els hem utilitzats per a analitzar les interaccions genètiques de FTc amb DETERMINATE i LATE FLOWERING, que són els homòlegs en pésol de TERMINAL FLOWER 1 d' Arabidopsis. Aquest anàlisi ha revelat una funció de FTc en el control de la floració i, curiosament, també en el desenvolupament del meristemo I2, estant aquesta segona funció possiblement mediada per la regulació de FTc en l'expressió de VEG1. / [EN] Inflorescence architecture determines position and number of flowers (and fruits) in the plant. This affects plant shape, contributing to morphological diversity, and also influences seed yield. Therefore, understanding the genetics behind inflorescence development is relevant not only to plant developmental biology but also to agriculture, to design new breeding strategies. Most legumes have compound inflorescences, in which the flowers do not form on the main stem but from secondary inflorescences (I2) at the flanks of the main primary inflorescence (I1). This is in contrast to plants with simple inflorescences, such as Arabidopsis, where the flowers directly form at the I1. Pea (Pisum sativum) belongs to the Fabaceae family and the galegoid clade of legumes and has a compound inflorescence. It is well known that VEGETATIVE1/ FULc (VEG1) encodes a transcription factor that specifies the identity of the I2 meristem in legumes, but it is still unknown how and through which genes VEG1 controls I2 development and the genetic pathways in which it is involved. In this work, we aimed to identify regulatory targets of VEG1. For that, we compared the transcriptomes of inflorescence apices from wild type and pea mutants with defects in inflorescence development: proliferating inflorescence meristems (pim - with multiple I2 meristems), veg1 and vegetative2 (veg2), none of which produce neither I2 meristems nor flowers). Using this approach, we have isolated I2-expressed meristem genes and identified some possible targets of VEG1, among them some genes that seem promising tools to improve yield in legumes. FLOWERING LOCUS T (FT) is a key regulator of the photoperiod inductive pathway that controls flowering time in Arabidopsis. In legumes, the FT clade has diversified into three subclades: FTa, FTb and FTc. Pea FTc is distant phylogenetically from the other FTs and has an unusual expression pattern, being expressed only at the inflorescence apex. In this work we have characterized pea ftc mutants and used them to analyze the genetic interactions of FTc with DETERMINATE and LATE FLOWERING, pea homologues of TERMINAL FLOWER 1 of Arabidopsis. This analysis has revealed a function of FTc in the control of flowering and, interestingly, of I2 meristem development, this second function being possibly mediated through FTc regulation of VEG1 expression. / Serra Picó, MP. (2022). New Insights into Pea Compound Inflorescence Development: Role of FTc and VEGETATIVE1 as Regulatory Factors [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/181299

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