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Prospecção de marcadores moleculares associados à resistência à giberela em trigo / Prospection of molecular markers associated with resistance to Fusarium head blight in wheatViana, Taiane Peres 04 December 2013 (has links)
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Previous issue date: 2013-12-04 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / O cultivo do trigo no Brasil é marcado pelo elevado número de doenças capazes de
causar danos à produção. Entre as principais doenças que afetam o trigo está a
giberela ou fusariose da espiga, causada pelo agente etiológico Gibberella zeae
(Schw.) Petch, (anamorfo Fusarium graminearum Schwabe) que causa impacto
negativos não somente à produtividade mas também a qualidade dos grãos
produzidos. As condições ambientais para que a infecção ocorra carac terizam-se
com temperaturas de 20-25°C e duração do molhamento foliar de, no mínimo, 48
horas consecutivas. O controle químico é realizado via aplicação de fungicidas a
partir do inicio da floração estendendo-se até o final do florescimento, sendo que
este tipo de controle caracteriza-se pela sua menor eficiência quando comparado
com o controle de doenças foliares. Caso as condições climáticas impeçam a
realização das aplicações de fungicidas no período indicado, o controle fica muito
dificultado, por outro lado, se não ocorrer clima favorável à infecção, não se justifica
o tratamento. A ineficiência dos tratos culturais no controle de giberela, associado à
natureza quantitativa da característica de resistência, e o fato de sofrer alta
influência do ambiente resultam na necessidade de identificar fontes efetivas de
resistência que possam ser utilizadas em programas de melhoramento de trigo. De
fato, existem culturas onde o controle das doenças mais importantes ocorre, quase
que exclusivamente, por meio da resistência sendo que a identificação de genotipos
que contenham resistência é um dos primeiros passos para selicioná-los. Desta
forma, é fundamental o conhecimento de cultivares que apresentem níveis de
resistência a giberela e métodos que possam identificar estas cultivares. Frente ao
exposto o objetivo deste trabalho foi: i) separar genótipos suscetíveis e que
contenham diferentes níveis de resistência utilizando avaliações morfológicas e
moleculares; ii) verificar a resistência à giberela nas cultivares Frontana e
Pampeano. Para isso foram utilizadas avaliações de características morfológicas
citadas na literatura e associadas a resistência à giberela, assim como, o meprego
de primers descritos na literatura significativamente associados à QTL de resistência
à giberela. Como resultado do estudo espera-se auxiliar no desenvolvimento de
ferramentas que possam ser utilizadas em programas de melhoramento de trigo
visando facilitar a identificação de fontes de resistência. / The cultivation of wheat in Brazil is marked by the large number of diseases that can
damage the production. Among the major diseases affecting wheat is wheat scab or
Fusarium head blight (FHB), caused by the agent Gibberella zeae (Schw.) Petch
(anamorph Fusarium graminearum Schwabe ) that causes negative impact not only
on productivity but also the quality of the grain produced. The environmental
conditions for infection are temperatures between 20-25°C and 48 consecutive hours
of leaf wetness. Chemical control is performed via application of fungicides from the
start extending until the end of flowering, and this type of control is characterized by
its low efficiency when compared to the disease control. If the weather conditions
prevent the aplication of fungicide applications within this period, there is no
possibility control, on the other hand, if it does not favorable environment for infec tion
treatment is not justified. The inefficiency of cultural control of FHB, associated with
the quantitative trait (QTL- Quantitative traits loci)of resistance, and the fact of
suffering high influence of the environment results in the need to identify effective
sources of resistance that can be used in wheat breeding programs. In fact, there are
cultures where control of major diseases occurs almost exclusively through
resistance where the identification of genotypes containing resist ance is one of the
first steps in their selection. Thus it is crucial to understand cultivar present levels of
resistance to FHB and methods that can identify these cultivars.The objective of this
study was: i) separate susceptible and containing different levels of resistance using
molecular and morphological evaluations; ii) determine FHB resistance using
cultivars Frontana and Pampeano as a source of resistance. Using morphological
assessments cited in the literature and associated with resistance to FHB, as,
primers as described in the literature as significantly associated with QTL for
resistance to FHB. As a result of the study one expects to develop tools that can be
used to facilitate the identification of sources of resistance.
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Transferabilidade de microssatélites de arroz para trigo na busca por marcadores ligados à resistência à fusariose / Transferability of microsatellite from rice to wheat in search of markers related to Fusarium head blight resistanceCarvalho, Alexandre Zanardo de 29 December 2007 (has links)
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Previous issue date: 2007-12-29 / Fusarium head blight (FHB) is one of the most important diseases known to
affect wheat crop. FHB, caused mainly by Fusarium graminearum, results in severe
losses of productivity and grain quality besides its harmful effects to human and
animal health due to the accumulation of mycotoxins in infected grains. Genetic
resistance is the best way to control FHB which affects crops in several parts of the
world. FHB resistance shows a quantitative heritage, hence are QTLs (quantitativetrait-
loci) that have a weak effect on character. Studies with microsatellite markers
have generated a great number of information related to the position of those QTLs
in the genome, in addition to the development of new varieties to be used in breeding
programs. The microsatellites are short sequence repeats, spread thoroughly in the
organism s genome. For amplification of those sequences it is used specific primers
to each loco. Due to the genetic relation between species, information generated
from the study in one species can be used successfully when studying related
species. Therefore, primers designed for microsatellites in one species can be used
to detect markers in related species and to associating those markers with
characteristics of interest. Here, the main objective of my work was to verify the
transferability of microsatellites from rice to wheat in search of markers related to
FHB resistance. It was tested different wheat genotypes showing different levels of
resistance to Fusarium and was verified the existence of polymorphism among those
genotypes. A number of 55 primer pairs of microsatellites isolated from the rice
genome were tested in 13 wheat cultivars classified as susceptible, moderately
susceptible, moderately resistant and resistant. In my results, the rate of
microsatellite transferability was of 76.4%, where from these, 23.8% showed
polymorphism and 76.2% showed monomorphism. In spite of the high rate of the
microsatellite transferability observed in my results, the analysis of polymorphism did
not allow the identification of markers that could be possibly associated with
resistance to Fusarium head blight in wheat. / A fusariose do trigo, causada principalmente pelo fungo Fusarium
graminearum, é uma das principais doenças nessa cultura, ocasionando perda de
produtividade e de qualidade de grãos, além dos efeitos nocivos à saúde do homem
e de animais devido ao acúmulo de micotoxinas nos grãos infectados. A resistência
genética é a melhor forma para o controle dessa patologia que atinge a cultura em
várias regiões do mundo. Ela exibe herança quantitativa, ou seja, são QTLs que tem
um pequeno efeito sobre o caráter. Estudos com marcadores de microssatélites têm
gerado um grande número de informações a respeito da posição desses QTLs no
genoma e no desenvolvimento de novas variedades para cultivo em programas de
melhoramento. Os microssatélites são pequenas seqüências de bases repetidas,
posicionadas adjacentemente e distribuídas amplamente no genoma dos
organismos. Para sua amplificação são utilizados primers específicos para cada
loco. As relações genéticas entre espécies permitem que informações geradas a
partir do estudo de uma delas sejam utilizadas para o estudo de espécies
relacionadas. Dessa forma, primers desenhados para locos de microssatélites em
uma espécie podem ser utilizados para detectar marcadores em espécies afins e
serem associados a características de interesse. Sendo assim, o objetivo deste
trabalho foi verificar a transferabilidade de locos de microssatélites de arroz para
genótipos de trigo com diferentes níveis de resistência à fusariose e verificar a
existência de polimorfismo entre os genótipos contrastantes que pudessem ser
associados à característica de resistência. Foram testados 55 pares de primers de
locos de microssatélites, isolados do genoma do arroz, em 13 cultivares de trigo,
classificadas como suscetíveis, moderadamente suscetíveis, moderadamente
resistentes e resistentes. Houve a transferabilidade de 76,4% desses locos de
microssatélites. Destes, 23,8% apresentaram polimorfismo e o restante, 76,2%,
apresentaram-se monomórficos. A análise do polimorfismo não permitiu a
identificação de marcadores que pudessem ser associados à resistência para
fusariose do trigo.
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Regulátor horkých vtoků pro vstřikovací formy plastu / Controller of hot runner for injection moldsChrenka, Eduard January 2016 (has links)
The thesis focuses on implementation of a hot runner controller for injection molds for plastic materials with a maximum number of 56 regulated zones. The first part of the thesis deals with already existing and used solutions of the given subject. The following part of the thesis describes the principles of temperature measurement by means of thermoelectric sensors, including their linearization as well as communication protocols MODBUS, EUROMAP 17. The identification of a regulated system ( heating zone) has been carried out before the hardware design. The development process is divided into some parts : system conception, hardware design, software development. The controller consists of measuring modules designed to collect data and handle power controllers for management of performance of heating elements. The necessary calculation power is integrated into the controllling computer. All parts of a hot runner controller are implemented taking into account the costs.
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SuperSampleRate-Filter in FPGAs für Subsample-Zeitauflösung und hochauflösende Energiemessung mit Gigasample-DigitizernJäger, Markus 28 March 2018 (has links)
Increasing sampling rates and sampling accuracies of analog-to-digital converters (ADCs) are growing the importance of digital data acquisition and signal processing for applications requiring high bandwidth. In this context, this work is focused on researching and developing new techniques and a new system architecture for optimal throughput and minimal intrinsic dead time. The investigations of this work concentrate on event processing systems by pulse shaping on SuperSampleRate (SSR) ADC data streams. SSR ADC data streams are data streams which require processing of more than one sample per clock cycle by digital circuits. To implement data processing in this work only Field Programmable Gate Arrays (FPGAs) are used, as they provide the right approach for high throughput and minimum dead time with ability to adapt to high- application-specific circuits afterwards.
As a result of this work a system architecture was developed which decouples the event acquisition and their processing inside the FPGA. This property is realized by a special FIFO structure in the FPGA. This concept achieves an intrinsic dead time of one ADC sample period and allows pre-processing of all channels by multiple instantiated processing cores and scheduling in hardware.
By means of this new system architecture, two conventional scientific measuring instruments based on analog technology were improved by digital data acquisition and signal processing. These measuring instruments are a spectrometer for time-differential perturbed angular correlations (TDPAC) and a digital spectrometer and data acquisition system at a nuclear microprobe for ion beam analysis and imaging. Both measuring instruments detect elementary particles or radiation emitted by the measuring sample by detectors as events. The time curves of several analog detector output signals (channels) are now recorded by ADCs and forwarded without loss as SSR data streams to one FPGA. The hardware used
here are FPGA digitizers which isolate the data acquisition and subsequent pre-processing by FPGAs into modules.
The improvement of the measuring efficiency of the two digital measuring instruments was achieved by minimizing the dead time, increasing the throughput, and by matching their time and energy resolutions with the conventional measuring instruments. Specifically to enable better time and energy resolutions combined with maximum throughput, this work has developed and implemented parallel processing SSR FIR and SSR IIR filters for pulse shaping as processing cores in the FPGAs which can handle multiple samples per clock cycle. To match the time resolution performance of conventional Constant Fraction Discriminators (CFDs) these filter implementations realize a digital Constant Fraction Trigger
(CFT) with fractional delays (below one sampling period). In this work the energy resolution was optimized by implementing a transfer function adjustable SSR IIR filter. Thus the filter provides maximum flexibility for pulse shaping of different detector types. By implementing the computationally intensive pre-processing in FPGAs, the measuring instruments could be equipped with only one underutilized PC, which can now implement new functionalities. These functionalities include a runtime-optimized coincidence measurement of stretched cascades (like for 180mHf) for the TDPAC spectrometer and a digital pileup rejection for the data acquisition system for ion beam analysis. / Die digitale Messwerterfassung und -verarbeitung erhält unter anderem durch steigende Abtastraten und Abtastgenauigkeiten von Analog-Digital-Wandlern (ADCs) wachsende Bedeutung für Anwendungen, welche eine hohe Bandbreite voraussetzen. In diesem Rahmen widmet sich diese Arbeit der Erforschung und Entwicklung neuer Techniken und einer neuen Systemarchitektur, mit denen eine Datenaufnahme und anschließende Signalverarbeitung, bei optimalem Durchsatz und minimaler intrinsische Totzeit umgesetzt werden kann. Die Untersuchungen fokussieren sich dabei auf Systeme zur Ereignisverarbeitung durch Impulsformung (pulse shaping) auf SuperSampleRate(SSR)-ADC-Datenströmen. SSR-ADC-Datenströme sind dabei ADC-Datenströme, welche eine Verarbeitung durch digitale Schaltungen benötigen, bei denen mehr als ein Sample pro Taktzyklus behandelt werden muss, um Datenverlust zu verhindern. Zur Implementierung der Datenverarbeitung kommen dazu ausschließlich Field Programmable Gate Arrays (FPGAs) zum Einsatz, da diese den passenden Ansatz für digitale Schaltungen mit hohen Durchsatz und minimaler Totzeit mit gleichzeitiger nachträglicher Anpassbarkeit für hoch anwendungsspezifische Schaltungen bieten.
Als Ergebnis wurde in dieser Arbeit eine Systemarchitektur entwickelt, welche die Ereigniserfassung und deren Verarbeitung im FPGA voneinander entkoppelt. Dies wird durch eine im FPGA realisierte FIFO-Struktur ermöglicht. Durch dieses Konzept wird eine intrinsische Totzeit der Systeme in der Größenordnung der ADC-Abtastperiodenlänge erreicht und eine Vorverarbeitung aller Kanäle durch mehrfache instanziierte Verarbeitungskerne und Scheduling in Hardware ermöglicht. Mittels dieser neuen Systemarchitektur werden zwei auf analogtechnisch basierende konventionelle wissenschaftliche Messinstrumente, durch digitale Messwerterfassung und Signalverarbeitung, verbessert. Bei diesen Messinstrumenten handelt es sich um ein Spektrometer zur zeitaufgelösten gestörten Winkelkorrelation (engl. Time Differential Perturbed Angular Correlation (kurz TDPAC-Spektrometer)) und ein Datenerfassungssystem zur ortsaufgelösten elementspezifischen Ionenstrahlanalyse und Ionenstrahlmikroskopie, welche im Wesentlichen von der Messprobe emittierte und durch Detektoren erfasste Elementarteilchen oder Strahlung als Ereignisse verarbeiten. Die Verläufe der analogen Detektorausgangssignale werden dabei mittels ADCs erfasst und verlustfrei als SSR-Datenströme an einen FPGA weitergeleitet. Dabei werden mehrere ADC-Datenströme (dann Kanäle genannt) von einem FPGA verarbeitet. Als Hardware kommen hier FPGA-Digitizer zum Einsatz. Diese Module isolieren die digitale Messwerterfassung durch ADCs und eine anschließende Vorverarbeitung von FPGAs, deren digitale Schaltung individuell implementiert werden kann, in eine Hardware. Eine Verbesserung der Messeffizienz der beiden digitalisierten Messinstrumente konnte durch die Minimierung der Totzeit, die Erhöhung des Durchsatzes aber auch durch die Anknüpfung ihrer Zeit- und Energieauflösung der detektierten Ereignisse erreicht werden. Speziell zur Ermöglichung besserer Zeit- und Energieauflösungen von Detektorereignissen mit maximalem Durchsatz wurden in dieser Arbeit SSR-FIR- und SSR-IIR-Filter zur Impulsformung als Verarbeitungskerne in den verwendeten FPGAs implementiert, welche pro Taktzyklus mehrere Samples verarbeiten können. Diese Filterimplementierungen setzen zur Optimierung der Zeitauflösung im Subsample-Bereich mit den Constant Fraction Trigger (CFT) an der Leistungsfähigkeit konventioneller Constant Fraction Discriminator (CFDs) an und ermöglichen ebenso Fractional Delays (Zeitverzögerungen unter einer Abtastperiode). Die Energieauflösung wurde in dieser Arbeit dadurch optimiert, dass der entwickelte SSR-IIR-Filter in seiner Übertragungsfunktion anpassbar ist und so maximale Flexibilität zur Impulsformung unterschiedlicher Detektortypen bietet. Durch die Umsetzung der rechenintensiven Vorverarbeitung in FPGAs konnten die Messinstrumente mit lediglich einem Mess-PC ausgestattet werden, welcher nun neue Funktionalitäten umsetzen kann. Zu diesen Funktionalitäten gehört eine laufzeitoptimierte Koinzidenzmessung gestreckter Kaskaden (Kaskade mit mehr als einem Start-Ereignis) für das TDPAC-Spektrometer und eine digitale Pileup-Verwerfung für das Datenerfassungssystem zur Ionenstrahlanalyse.
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Sexualitet, samtycke och relationer i fem svenska läroböcker : En kvalitativ innehållsanalys av skönlitteratur och SSR i fem olika läroböcker för svenska 1 på gymnasieskolanVikenäs, Sanne January 2023 (has links)
Syftet med denna kvalitativa innehållsanalys är att undersöka hur lärare i svenskämnet för gymnasiet kan arbeta med skönlitteratur kopplat till sexualitet, samtycke och relationer som värdegrundsrelaterade frågor. Frågeställningarna som används handlar om hur läroböckerna tar upp och behandlar de värdegrundsrelaterade fenomenen sexualitet, samtycke och relationer ur en skönlitterär aspekt och vilken syn på sexualitet och samtycke som framställs i läroböckernas litteraturutdrag. För att uppfylla syftet och besvara frågeställningarna utförs en kvalitativ innehållsanalys av fem läroböcker avsedda för kursen svenska 1 på gymnasiet. Slutsatsen är att Skolverkets öppna formuleringar om vilken skönlitteratur gymnasieelever ska få tillgång till, ger lärarna en stor autonomi. De värdegrundsrelaterade fenomenen sexualitet, samtycke och relationer finns alla representerade i läroböckerna men i olika utsträckning. Synen på sexualitet som framställs är starkt heteronormativ och även om fenomenet samtycke finns med är det väldigt få utdrag som ger substans till exemplifieringar på såväl givet samtycke som brist på samtycke. Det är väldigt tydligt att just fenomenet samtycke är något som behöver belysas tydligare i den litteratur som är aktuell i de fem läroböckerna. Betydelsen av att öka kunskapen kring detta fenomen visas i och med den relativt nya lagen samt tillägget i värdegrunden, som tydligt indikerar vikten av ökad förståelse kring SSR-fenomenen.
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Dissection of black rot resistance towards marker-assisted breeding in grapevine Pedigree reconstruction and phenotyping optimization coupled with high-density linkage mapping revealed a major QTL associated with bunch resistance.Bettinelli, Paola 05 June 2023 (has links)
Viticulture is a multibillion-dollar market based on grapes, one of the most valuable fruits in agriculture, but it is also characterized by the highest uses of fungicides per hectare for disease management. In fact, despite the availability of genetic resources resistant to the most diffuse fungal pathogens, those cover less than a fifth of the worldwide vine area. The remaining 80% is represented mainly by susceptible Vitis vinifera L. varieties. Instead, re-sistance traits are known to derive from other Vitis species, due to their coevolution with the pathogens, and their exploitation in breeding is a valuable strategy to reduce pesticide treat-ments. Black rot (BR) is a destructive disease caused by the ascomycete, Phyllosticta ampeli-cida, whose telomorphic form was known as Guignardia bidwellii. In the European continental area in the last two decades its pressure increased due to the concomitant decreased usage of chemicals and the occurrence of mild-rainy summer because of the climate change. This work was established to fight the spread of BR by means of the introduction of BR resistance in susceptible genetic background. The study consisted of (i) the reconstruction of BR resistant donor pedigree based on the collection of historical phenotypic data, (ii) the eval-uation of parental lines and selections of the breeding program of the Edmund Mach Founda-tion (Italy), (iii) the microscopic inspection of disease progression, and (iv) QTL analysis of the segregating population (N=146) ‘Merzling’ (hybrid, resistant) × ‘Teroldego’ (V. vinifera, suscep-tible). The outcomes revealed a large unexplored pool of disease resistance donors of 148 va-rieties belonging to 14 different species, that permitted to evaluate and identify five new promising genotypes readily exploited for breeding. Concurrently, a new inoculation method based on spore production from fresh infected leaves was developed. Ex vivo (detached leaves) inoculation did not reveal significant differences among the assessed genotypes and highlight-ed the tendency of spores to accumulate and germinate near leaf hairs, while disease progres-sion did not occur. The screening of the segregating population, both under greenhouse and field conditions, allowed the discrimination on chromosome 14 between two distinct QTLs as-sociated with leaf/shoot and bunch resistance. The first QTL confirmed the Resistance to Gui-gnardia bidwellii (Rgb)1 locus previously identified by three studies and the high-density link-age mapping allowed to reduce it from 2.4 to 0.7 Mb along the PN40024.v4 reference genome. The region resulted enriched in genes belonging to phloem dynamics and mitochondrial pro-ton transfer. The second QTL associated with bunch resistance was designated Rgb3. Located at 9 cM (6 Mb) upstream Rgb1, it was characterized by a cluster of Germin-like protein 3 genes and lipid transfer and localization, notably known to be linked to broad spectrum disease re-sistance and stress response. No resistance (R)-genes have been annotated in the region under-lying the QTL in the PN40024 reference genome. In conclusion, this work provided new insights for grapevine breeding programs by the identification of previously unknown BR resistance donors, the development of protocols and good practices towards large-scale resistance screening as well as the discovery of a novel QTL associated with bunch resistance. Marker validation in different genetic backgrounds is ongoing for its routinary implementation in marker-assisted breeding and further studies are planned to dissect BR resistance mechanism by the sequencing of the genomic regions, the study of the Germin-like 3 gene cluster and the cell wall characterization.
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Weedy rice (Oryza sativa ssp.): an untapped genetic resource for abiotic stress tolerant traits for rice improvementStallworth, Shandrea D. 06 August 2021 (has links)
Rice (Oryza sativa) is the staple food for more than 3.5 billion people worldwide. As the population continues to grow, rice yield will need to increase by 1% every year for the next 30 years to keep up with the growth. In the US, Arkansas accounts for more than 50% of rice production. Over the last 68 years, rice production has continued to grow in Mississippi, placing it in fourth place after Arkansas, Louisiana, and California. Due to increasing rice acreage, regionally and worldwide, the need to develop abiotic stress-tolerant rice has increased. Unfortunately, current rice breeding programs lack genetic diversity, and many traits have been lost through the domestication of cultivated rice. Currently, stressors stemming from the continued effects of climate change continue to impact rice. To counteract the impacts of climate change, research has shifted to evaluating wild and weedy relatives of rice to improve breeding techniques. Weedy rice (Oryza sativa ssp.) is a genetically similar, noxious weed in rice with increased competitive ability. Studies have demonstrated that weedy rice has increased genetic variability and inherent tolerance to abiotic stressors. The aims of this study were to 1) screen a weedy rice mini-germplasm for tolerance to cold, heat, and complete submergence-stress, 2) utilize simple sequence repeat (SSR) markers and single nucleotide polymorphisms to evaluate the genetic diversity of the weedy rice population, and 3) use genome-wide association (GWAS) to identify SNPs associated with candidate genes within the population.
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Molecular marker analysis of adult plant resistance to powdery mildew in common wheatLiu, Sixin 05 January 2000 (has links)
Powdery mildew, caused by Blumeria graminis (DC.) E.O. Speer f. sp. tritici E'm. Marchal (syn. Erysiphe graminis f. sp. tritici), is one of the major diseases of wheat (Triticum aestivum L.) worldwide. The use of cultivars with resistance to powdery mildew is an efficient, economical and environmentally safe way to control powdery mildew. Race-specific resistance has been extensively used in breeding programs; however, it is ephemeral. Adult plant resistance (APR) to powdery mildew is more durable as demonstrated by the cultivar Massey, which has maintained its APR to powdery mildew since its release in 1981. To develop an efficient breeding strategy, it is essential to understand the genetic basis of APR. The objectives of this study were to identify molecular markers associated with APR to powdery mildew in common wheat Massey and to verify their association using recombinant inbred (RI) lines.
A cross was made between the powdery mildew susceptible cultivar Becker and Massey. One hundred and eighty F2:3 lines were rated for disease severity under natural pressure of powdery mildew in field. Using both restriction fragment length polymorphism (RFLP) and microsatellite markers, three quantitative trait loci (QTL), designated as QPm.vt-1B, QPm.vt-2A and QPm.vt-2B, were identified in the Becker x Massey F2:3 generation. These loci are located on chromosomes 1B, 2A and 2B, respectively, and explained 17%, 29% and 11% of the total variation among F2:3 lines for powdery mildew resistance, respectively. Cumulatively, the three QTLs explained 50% of the phenotypic variation among F2:3 lines in a multi-QTL model. The three QTLs associated with APR to powdery mildew were derived from Massey and displayed additive gene action. QPm.vt-2B also fits a recessive model for APR to powdery mildew.
In the second part of this study, 97 RI lines were developed from the Becker x Massey cross. The RI lines were evaluated for APR to powdery mildew under natural disease pressure for three years. Both single marker analysis and interval mapping confirmed the presence of the three QTLs identified in the F2:3 generation. The three QTLs, QPm.vt-1B, QPm.vt-2A and QPm.vt-2B, accounted for 15%, 26% and 15% of the variation of mean powdery mildew severity of the RI lines over three years. In a multi-QTL model, the three QTLs explained 44% of the phenotypic variation of the RI lines. The RI lines were grouped according to the genotype of the three QTLs, represented by markers GWM304a, KSUD22 and PSP3100, respectively. The RI lines with Massey alleles at all three loci had a mean disease severity of 3.4%, whereas the RI lines with Becker alleles at all three loci had a mean disease severity of 22.3%. These severity values are similar to those of the corresponding parents.
The molecular markers identified and verified as to their association with APR to powdery mildew in Massey have the potential for use in marker-assisted selection for resistance to powdery mildew and in pyramiding powdery mildew resistance genes, as well as facilitating a better understanding of the molecular basis of APR to powdery mildew. / Ph. D.
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Desarrollo y aplicación de herramientas genómicas para la mejora de especies cucurbitáceas por calidad y resistencia a enfermedadesEsteras Gómez, Cristina 11 September 2012 (has links)
El melón (Cucumis melo) y el calabacín (Cucurbita pepo) son especies cucurbitáceas de gran importancia económica a nivel nacional y mundial. Para optimizar su producción se requiere de la obtención de nuevas variedades mejor adaptadas a los sistemas de cultivo, más resistentes frente a nuevas enfermedades o plagas y con mejores características organolépticas, que respondan a las cada vez mayores exigencias del mercado. La mejora debe realizarse de una forma eficiente y competitiva, apoyándose en los crecientes conocimientos genéticos en estas dos especies y en los últimos avances biotecnológicos. El desarrollo de herramientas genómicas con el fin de impulsar la mejora de estos cultivos es el principal objetivo de la presente Tesis doctoral.
El desarrollo de marcadores moleculares es esencial para la construcción de mapas genéticos, para la realización de una selección más eficiente, para el análisis y cartografía de QTLs (Quantitative trait loci) y para el desarrollo de líneas de premejora, además de ser una herramienta fundamental para el análisis de la biodiversidad. En esta Tesis se han desarrollo y/o validado marcadores de alta calidad, de tipo microsatélite (Simple Sequence Repeats, SSRs) y SNPs (Single Nucleotide Polymorphisms), para estas dos especies. La generación de información de secuencia, necesaria para el desarrollo de este tipo de marcadores, ha cambiado en el transcurso de los trabajos presentados en la Tesis, habiéndose abordado finalmente la secuenciación del transcriptoma de melón mediante técnicas de secuenciación de alto rendimiento (NGS, Next generation sequencing). La obtención de grandes colecciones de SSRs y SNPs en ambas especies, resultado del ensamblaje de ESTs (Expressed Sequence Tags) procedentes de secuencias Sanger previamente disponibles y de las nuevas secuencias obtenidas por secuenciación masiva, ha supuesto un gran avance para estas especies no modelo, permitiendo la construcción de mapas más densos en melón y del primer mapa ba / Esteras Gómez, C. (2012). Desarrollo y aplicación de herramientas genómicas para la mejora de especies cucurbitáceas por calidad y resistencia a enfermedades [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/17046
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"Det har blivit en sån grej som ska bli inkluderad i alla ämnen, så därför blir det inkluderat i inget" : En studie om sexualitet, samtycke och relationer i samhällskunskapen / "It has become a thing that is supposed to be included in all subjects, and therefore becomes included in none" : A study about sexuality, consent and relationships in social scienceLandtmanson, Ingrid, Lexert, Tilda January 2024 (has links)
The #MeToo movement exposed widespread vulnerability to sexual abuse, while digitalization increased online risks for youth. Recent changes in the curriculum for the Swedish Upper Secondary school have expanded sexual education, emphasizing consent and relationships, underscoring its importance across school activities, including the subject social studies. Despite the potential for integrating these themes, research indicates reluctance among several teachers. Research primarily focuses on teaching methods from both teacher and student perspectives, yet there is a gap in understanding teachers of social studies needs and challenges in light of these new curriculum guidelines, hence the purpose of this study. Our aim is to capture a result that can develop sexual education, furthermore get an insight into what teachers need to integrate the topic of sexuality, consent and relationships. We gathered empirical material using mixed methods; a questionnaire survey and semi-structured interviews. The result, presented through thematic analysis and discussed using theoretical concepts and current research, shows that teachers of social studies lack a unified view on integrating these topics due to the broad curriculum, as they have varied experiences, unclear guidelines or insufficient preparation. Challenges include content overload, time constraints and the sensitivity of the subject. Teachers navigate these challenges using their pedagogical skills and relationship-building, highlighting the need for clearer guidelines, collaborative work, and professional development to effectively address the controversial topics that the subject can arise. The subject is crucial for students' lives and their future as democratic citizens. We propose reviewing the guidelines and the curriculum of social studies to provide concrete guidance for teachers. This would ensure the subject is neither forgotten nor overwhelming and reduce the risk of it being intended to be covered in all subjects but actually included in none.
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